Merge "EffectProxy return the active sub-effect descriptor" into main
diff --git a/camera/ndk/impl/ACameraMetadata.cpp b/camera/ndk/impl/ACameraMetadata.cpp
index 4995dc4..1fd4a86 100644
--- a/camera/ndk/impl/ACameraMetadata.cpp
+++ b/camera/ndk/impl/ACameraMetadata.cpp
@@ -400,7 +400,6 @@
 
     camera_metadata_ro_entry rawEntry = static_cast<const CameraMetadata*>(mData.get())->find(tag);
     if (rawEntry.count == 0) {
-        ALOGE("%s: cannot find metadata tag %d", __FUNCTION__, tag);
         return ACAMERA_ERROR_METADATA_NOT_FOUND;
     }
     entry->tag = tag;
diff --git a/cmds/stagefright/stagefright.cpp b/cmds/stagefright/stagefright.cpp
index 2edc0fe..379f244 100644
--- a/cmds/stagefright/stagefright.cpp
+++ b/cmds/stagefright/stagefright.cpp
@@ -106,6 +106,12 @@
     decodeTimesUs->sort(CompareIncreasing);
 
     size_t n = decodeTimesUs->size();
+
+    if (n == 0) {
+        printf("no decode histogram to display\n");
+        return;
+    }
+
     int64_t minUs = decodeTimesUs->itemAt(0);
     int64_t maxUs = decodeTimesUs->itemAt(n - 1);
 
diff --git a/drm/libmediadrmrkp/Android.bp b/drm/libmediadrmrkp/Android.bp
index e4a7a81..f13eb62 100644
--- a/drm/libmediadrmrkp/Android.bp
+++ b/drm/libmediadrmrkp/Android.bp
@@ -9,9 +9,15 @@
     ],
     shared_libs: [
         "libbinder_ndk",
+        "libcrypto",
         "liblog",
+    ],
+    static_libs: [
+        "android.hardware.common-V2-ndk",
         "android.hardware.drm-V1-ndk",
         "android.hardware.security.rkp-V3-ndk",
+        "libbase",
+        "libcppbor_external",
     ],
     defaults: [
         "keymint_use_latest_hal_aidl_ndk_shared",
@@ -30,10 +36,13 @@
     shared_libs: [
         "libbinder_ndk",
         "liblog",
-        "android.hardware.drm-V1-ndk",
-        "android.hardware.security.rkp-V3-ndk",
     ],
     static_libs: [
+        "android.hardware.common-V2-ndk",
+        "android.hardware.drm-V1-ndk",
+        "android.hardware.security.rkp-V3-ndk",
+        "libbase",
+        "libcppbor_external",
         "libmediadrmrkp",
     ],
     vendor: true,
diff --git a/drm/libmediadrmrkp/include/DrmRemotelyProvisionedComponent.h b/drm/libmediadrmrkp/include/DrmRemotelyProvisionedComponent.h
index 893f560..f046785 100644
--- a/drm/libmediadrmrkp/include/DrmRemotelyProvisionedComponent.h
+++ b/drm/libmediadrmrkp/include/DrmRemotelyProvisionedComponent.h
@@ -20,6 +20,7 @@
 #include <aidl/android/hardware/drm/IDrmPlugin.h>
 #include <aidl/android/hardware/security/keymint/BnRemotelyProvisionedComponent.h>
 #include <aidl/android/hardware/security/keymint/RpcHardwareInfo.h>
+#include <cppbor.h>
 
 namespace android::mediadrm {
 
@@ -34,7 +35,7 @@
 class DrmRemotelyProvisionedComponent : public BnRemotelyProvisionedComponent {
   public:
     DrmRemotelyProvisionedComponent(std::shared_ptr<IDrmPlugin> drm, std::string drmVendor,
-                                    std::string drmDesc);
+                                    std::string drmDesc, std::vector<uint8_t> bcc);
     ScopedAStatus getHardwareInfo(RpcHardwareInfo* info) override;
 
     ScopedAStatus generateEcdsaP256KeyPair(bool testMode, MacedPublicKey* macedPublicKey,
@@ -52,9 +53,13 @@
                                                std::vector<uint8_t>* csr) override;
 
   private:
+    ScopedAStatus getVerifiedDeviceInfo(cppbor::Map& deviceInfoMap);
+    ScopedAStatus getDeviceInfo(std::vector<uint8_t>* deviceInfo);
+
     std::shared_ptr<IDrmPlugin> mDrm;
     std::string mDrmVendor;
     std::string mDrmDesc;
+    std::vector<uint8_t> mBcc;
 };
 }  // namespace android::mediadrm
 
diff --git a/drm/libmediadrmrkp/src/DrmRemotelyProvisionedComponent.cpp b/drm/libmediadrmrkp/src/DrmRemotelyProvisionedComponent.cpp
index 9d11811..440be79 100644
--- a/drm/libmediadrmrkp/src/DrmRemotelyProvisionedComponent.cpp
+++ b/drm/libmediadrmrkp/src/DrmRemotelyProvisionedComponent.cpp
@@ -16,13 +16,24 @@
 
 #define LOG_TAG "DrmRemotelyProvisionedComponent"
 #include "DrmRemotelyProvisionedComponent.h"
+
+#include <android-base/properties.h>
+#include <cppbor.h>
+#include <cppbor_parse.h>
 #include <log/log.h>
+#include <map>
+#include <string>
 
 namespace android::mediadrm {
 DrmRemotelyProvisionedComponent::DrmRemotelyProvisionedComponent(std::shared_ptr<IDrmPlugin> drm,
                                                                  std::string drmVendor,
-                                                                 std::string drmDesc)
-    : mDrm(std::move(drm)), mDrmVendor(std::move(drmVendor)), mDrmDesc(std::move(drmDesc)) {}
+                                                                 std::string drmDesc,
+                                                                 std::vector<uint8_t> bcc)
+    : mDrm(std::move(drm)),
+      mDrmVendor(std::move(drmVendor)),
+      mDrmDesc(std::move(drmDesc)),
+      mBcc(std::move(bcc)) {}
+
 ScopedAStatus DrmRemotelyProvisionedComponent::getHardwareInfo(RpcHardwareInfo* info) {
     info->versionNumber = 3;
     info->rpcAuthorName = mDrmVendor;
@@ -47,10 +58,79 @@
             "generateCertificateRequest not supported."));
 }
 
+ScopedAStatus DrmRemotelyProvisionedComponent::getVerifiedDeviceInfo(cppbor::Map& deviceInfoMap) {
+    std::vector<uint8_t> verifiedDeviceInfo;
+    auto status = mDrm->getPropertyByteArray("verifiedDeviceInfo", &verifiedDeviceInfo);
+    if (!status.isOk()) {
+        ALOGE("getPropertyByteArray verifiedDeviceInfo failed. Details: [%s].",
+              status.getDescription().c_str());
+        return status;
+    }
+
+    auto [parsed, _, err] = cppbor::parse(
+            reinterpret_cast<const uint8_t*>(verifiedDeviceInfo.data()), verifiedDeviceInfo.size());
+
+    if (!parsed || !parsed->asMap()) {
+        ALOGE("Failed to parse the verified device info cbor: %s", err.c_str());
+        return ScopedAStatus(AStatus_fromServiceSpecificErrorWithMessage(
+                IRemotelyProvisionedComponent::STATUS_FAILED,
+                "Failed to parse the verified device info cbor."));
+    }
+
+    const cppbor::Map* verifiedDeviceInfoMap = parsed->asMap();
+    for (size_t i = 0; i < verifiedDeviceInfoMap->size(); i++) {
+        auto& [keyItem, valueItem] = (*verifiedDeviceInfoMap)[i];
+        ALOGI("Found device info %s", keyItem->asTstr()->value().data());
+        if (valueItem != nullptr && valueItem->asTstr() != nullptr &&
+            valueItem->asTstr()->value().empty()) {
+            ALOGI("Value is empty. Skip");
+            continue;
+        }
+        deviceInfoMap.add(keyItem->clone(), valueItem->clone());
+    }
+
+    return ScopedAStatus::ok();
+}
+
+ScopedAStatus DrmRemotelyProvisionedComponent::getDeviceInfo(std::vector<uint8_t>* deviceInfo) {
+    auto deviceInfoMap = cppbor::Map();
+    auto status = getVerifiedDeviceInfo(deviceInfoMap);
+    if (!status.isOk()) {
+        ALOGE("getVerifiedDeviceInfo failed. Details: [%s].", status.getDescription().c_str());
+        return status;
+    }
+    const std::map<std::string, std::string> keyToProp{{"brand", "ro.product.brand"},
+                                                       {"manufacturer", "ro.product.manufacturer"},
+                                                       {"model", "ro.product.model"},
+                                                       {"device", "ro.product.device"},
+                                                       {"product", "ro.product.name"}};
+    for (auto i : keyToProp) {
+        auto key = i.first;
+        auto prop = i.second;
+        const auto& val= deviceInfoMap.get(key);
+        if (val == nullptr || val->asTstr()->value().empty()) {
+            std::string propValue = android::base::GetProperty(prop, "");
+            if (propValue.empty()) {
+                ALOGE("Failed to get OS property %s", prop.c_str());
+                return ScopedAStatus(AStatus_fromServiceSpecificErrorWithMessage(
+                        IRemotelyProvisionedComponent::STATUS_FAILED,
+                        "Failed to get OS property."));
+            }
+            deviceInfoMap.add(cppbor::Tstr(key), cppbor::Tstr(propValue));
+            ALOGI("use OS property %s: %s", prop.c_str(), propValue.c_str());
+        } else {
+            ALOGI("use verified key %s: %s", key.c_str(), val->asTstr()->value().data());
+        }
+    }
+    deviceInfoMap.canonicalize();
+    *deviceInfo = deviceInfoMap.encode();
+    return ScopedAStatus::ok();
+}
+
 ScopedAStatus DrmRemotelyProvisionedComponent::generateCertificateRequestV2(
         const std::vector<MacedPublicKey>&, const std::vector<uint8_t>& challenge,
-        std::vector<uint8_t>* csr) {
-    // extract csr using setPropertyByteArray/getPropertyByteArray
+        std::vector<uint8_t>* out) {
+    // access csr input/output via setPropertyByteArray/getPropertyByteArray
     auto status = mDrm->setPropertyByteArray("certificateSigningRequestChallenge", challenge);
     if (!status.isOk()) {
         ALOGE("setPropertyByteArray certificateSigningRequestChallenge failed. Details: [%s].",
@@ -58,13 +138,35 @@
         return status;
     }
 
-    status = mDrm->getPropertyByteArray("certificateSigningRequest", csr);
+    std::vector<uint8_t> deviceInfo;
+    status = getDeviceInfo(&deviceInfo);
     if (!status.isOk()) {
-        ALOGE("getPropertyByteArray certificateSigningRequest failed. Details: [%s].",
+        ALOGE("getDeviceInfo failed. Details: [%s].", status.getDescription().c_str());
+        return status;
+    }
+
+    status = mDrm->setPropertyByteArray("deviceInfo", deviceInfo);
+    if (!status.isOk()) {
+        ALOGE("setPropertyByteArray deviceInfo failed. Details: [%s].",
               status.getDescription().c_str());
         return status;
     }
 
+    std::vector<uint8_t> deviceSignedCsrPayload;
+    status = mDrm->getPropertyByteArray("deviceSignedCsrPayload", &deviceSignedCsrPayload);
+    if (!status.isOk()) {
+        ALOGE("getPropertyByteArray deviceSignedCsrPayload failed. Details: [%s].",
+              status.getDescription().c_str());
+        return status;
+    }
+
+    // assemble AuthenticatedRequest (definition in IRemotelyProvisionedComponent.aidl)
+    *out = cppbor::Array()
+                   .add(1 /* version */)
+                   .add(cppbor::Map() /* UdsCerts */)
+                   .add(cppbor::EncodedItem(mBcc))
+                   .add(cppbor::EncodedItem(std::move(deviceSignedCsrPayload)))
+                   .encode();
     return ScopedAStatus::ok();
 }
 }  // namespace android::mediadrm
\ No newline at end of file
diff --git a/drm/libmediadrmrkp/src/DrmRkpAdapter.cpp b/drm/libmediadrmrkp/src/DrmRkpAdapter.cpp
index a2d4cc1..515d157 100644
--- a/drm/libmediadrmrkp/src/DrmRkpAdapter.cpp
+++ b/drm/libmediadrmrkp/src/DrmRkpAdapter.cpp
@@ -79,12 +79,21 @@
                     return;
                 }
 
-                std::string compName = "DrmRemotelyProvisionedComponent_" + std::string(instance);
+                std::vector<uint8_t> bcc;
+                status = mDrm->getPropertyByteArray("bootCertificateChain", &bcc);
+                if (!status.isOk()) {
+                    ALOGE("mDrm->getPropertyByteArray(\"bootCertificateChain\") failed."
+                          "Detail: [%s].",
+                          status.getDescription().c_str());
+                    return;
+                }
+
+                std::string compName(instance);
                 auto comps = static_cast<
                         std::map<std::string, std::shared_ptr<IRemotelyProvisionedComponent>>*>(
                         context);
                 (*comps)[compName] = ::ndk::SharedRefBase::make<DrmRemotelyProvisionedComponent>(
-                        mDrm, drmVendor, drmDesc);
+                        mDrm, drmVendor, drmDesc, bcc);
             });
     return comps;
 }
diff --git a/include/media/VolumeShaper.h b/include/media/VolumeShaper.h
index 5271e10..6208db3 100644
--- a/include/media/VolumeShaper.h
+++ b/include/media/VolumeShaper.h
@@ -1099,7 +1099,7 @@
      * internal to the VolumeHandler.
      */
     void setIdIfNecessary(const sp<VolumeShaper::Configuration> &configuration) {
-        if (configuration->getType() == VolumeShaper::Configuration::TYPE_SCALE) {
+        if (configuration && configuration->getType() == VolumeShaper::Configuration::TYPE_SCALE) {
             const int id = configuration->getId();
             if (id == -1) {
                 // Reassign to a unique id, skipping system ids.
diff --git a/media/codec2/sfplugin/utils/Codec2CommonUtils.cpp b/media/codec2/sfplugin/utils/Codec2CommonUtils.cpp
index bb6c1b8..f428fce 100644
--- a/media/codec2/sfplugin/utils/Codec2CommonUtils.cpp
+++ b/media/codec2/sfplugin/utils/Codec2CommonUtils.cpp
@@ -83,7 +83,7 @@
     }
 
     // Default scenario --- the consumer is display or GPU
-    const AHardwareBuffer_Desc desc = {
+    const AHardwareBuffer_Desc consumableForDisplayOrGpu = {
             .width = 320,
             .height = 240,
             .format = format,
@@ -98,7 +98,7 @@
     };
 
     // The consumer is a HW encoder
-    const AHardwareBuffer_Desc descHwEncoder = {
+    const AHardwareBuffer_Desc consumableForHwEncoder = {
             .width = 320,
             .height = 240,
             .format = format,
@@ -114,7 +114,7 @@
     };
 
     // The consumer is a SW encoder
-    const AHardwareBuffer_Desc descSwEncoder = {
+    const AHardwareBuffer_Desc consumableForSwEncoder = {
             .width = 320,
             .height = 240,
             .format = format,
@@ -128,9 +128,9 @@
             .rfu1 = 0,
     };
 
-    return AHardwareBuffer_isSupported(&desc)
-            && AHardwareBuffer_isSupported(&descHwEncoder)
-            && AHardwareBuffer_isSupported(&descSwEncoder);
+    return AHardwareBuffer_isSupported(&consumableForDisplayOrGpu)
+            && AHardwareBuffer_isSupported(&consumableForHwEncoder)
+            && AHardwareBuffer_isSupported(&consumableForSwEncoder);
 }
 
 }  // namespace android
diff --git a/media/libaaudio/src/core/AudioStream.cpp b/media/libaaudio/src/core/AudioStream.cpp
index 56ef1e6..e0fd325 100644
--- a/media/libaaudio/src/core/AudioStream.cpp
+++ b/media/libaaudio/src/core/AudioStream.cpp
@@ -134,7 +134,8 @@
             .set(AMEDIAMETRICS_PROP_ENCODINGHARDWARE,
                     android::toString(getHardwareFormat()).c_str())
             .set(AMEDIAMETRICS_PROP_CHANNELCOUNTHARDWARE, (int32_t)getHardwareSamplesPerFrame())
-            .set(AMEDIAMETRICS_PROP_SAMPLERATEHARDWARE, (int32_t)getHardwareSampleRate());
+            .set(AMEDIAMETRICS_PROP_SAMPLERATEHARDWARE, (int32_t)getHardwareSampleRate())
+            .set(AMEDIAMETRICS_PROP_SAMPLERATECLIENT, (int32_t)getSampleRate());
 
         if (getDirection() == AAUDIO_DIRECTION_OUTPUT) {
             item.set(AMEDIAMETRICS_PROP_PLAYERIID, mPlayerBase->getPlayerIId());
diff --git a/media/libaudioclient/aidl/fuzzer/Android.bp b/media/libaudioclient/aidl/fuzzer/Android.bp
index 1ca3042..67258d9 100644
--- a/media/libaudioclient/aidl/fuzzer/Android.bp
+++ b/media/libaudioclient/aidl/fuzzer/Android.bp
@@ -20,11 +20,8 @@
         "android.hardware.audio.common@7.0-enums",
         "effect-aidl-cpp",
         "liblog",
-        "libbinder_random_parcel",
-        "libbase",
         "libcgrouprc",
         "libcgrouprc_format",
-        "libcutils",
         "libjsoncpp",
         "libmediametricsservice",
         "libmedia_helper",
@@ -55,14 +52,11 @@
         "libaudiopolicy",
         "libaudioutils",
         "libdl",
-        "libutils",
         "libxml2",
         "mediametricsservice-aidl-cpp",
         "framework-permission-aidl-cpp",
         "libvndksupport",
         "libmediametrics",
-        "libbinder_ndk",
-        "libbinder",
         "libfakeservicemanager",
         "libactivitymanager_aidl",
         "libheadtracking",
@@ -100,5 +94,8 @@
 cc_fuzz {
     name: "audioflinger_aidl_fuzzer",
     srcs: ["audioflinger_aidl_fuzzer.cpp"],
-    defaults: ["libaudioclient_aidl_fuzzer_defaults"],
+    defaults: [
+        "libaudioclient_aidl_fuzzer_defaults",
+        "service_fuzzer_defaults"
+    ],
 }
diff --git a/media/libaudioclient/tests/audiorouting_tests.cpp b/media/libaudioclient/tests/audiorouting_tests.cpp
index 19d1abc..e6916cc 100644
--- a/media/libaudioclient/tests/audiorouting_tests.cpp
+++ b/media/libaudioclient/tests/audiorouting_tests.cpp
@@ -53,7 +53,7 @@
         ASSERT_NE(nullptr, ap);
         ASSERT_EQ(OK, ap->loadResource("/data/local/tmp/bbb_2ch_24kHz_s16le.raw"))
                 << "Unable to open Resource";
-        EXPECT_EQ(OK, ap->create()) << "track creation failed";
+        ASSERT_EQ(OK, ap->create()) << "track creation failed";
         sp<OnAudioDeviceUpdateNotifier> cb = sp<OnAudioDeviceUpdateNotifier>::make();
         EXPECT_EQ(OK, ap->getAudioTrackHandle()->addAudioDeviceCallback(cb));
         EXPECT_EQ(OK, ap->start()) << "audio track start failed";
@@ -87,7 +87,7 @@
     sp<AudioCapture> capture = sp<AudioCapture>::make(
             AUDIO_SOURCE_REMOTE_SUBMIX, 48000, AUDIO_FORMAT_PCM_16_BIT, AUDIO_CHANNEL_IN_STEREO);
     ASSERT_NE(nullptr, capture);
-    EXPECT_EQ(OK, capture->create()) << "record creation failed";
+    ASSERT_EQ(OK, capture->create()) << "record creation failed";
     sp<OnAudioDeviceUpdateNotifier> cbCapture = sp<OnAudioDeviceUpdateNotifier>::make();
     EXPECT_EQ(OK, capture->getAudioRecordHandle()->addAudioDeviceCallback(cbCapture));
 
@@ -98,7 +98,7 @@
     ASSERT_NE(nullptr, playback);
     ASSERT_EQ(OK, playback->loadResource("/data/local/tmp/bbb_2ch_24kHz_s16le.raw"))
             << "Unable to open Resource";
-    EXPECT_EQ(OK, playback->create()) << "track creation failed";
+    ASSERT_EQ(OK, playback->create()) << "track creation failed";
     sp<OnAudioDeviceUpdateNotifier> cbPlayback = sp<OnAudioDeviceUpdateNotifier>::make();
     EXPECT_EQ(OK, playback->getAudioTrackHandle()->addAudioDeviceCallback(cbPlayback));
 
@@ -180,7 +180,7 @@
     ASSERT_NE(nullptr, playback);
     ASSERT_EQ(OK, playback->loadResource("/data/local/tmp/bbb_2ch_24kHz_s16le.raw"))
             << "Unable to open Resource";
-    EXPECT_EQ(OK, playback->create()) << "track creation failed";
+    ASSERT_EQ(OK, playback->create()) << "track creation failed";
     sp<OnAudioDeviceUpdateNotifier> cbPlayback = sp<OnAudioDeviceUpdateNotifier>::make();
     EXPECT_EQ(OK, playback->getAudioTrackHandle()->addAudioDeviceCallback(cbPlayback));
 
@@ -188,7 +188,7 @@
     sp<AudioCapture> captureA = sp<AudioCapture>::make(
             AUDIO_SOURCE_REMOTE_SUBMIX, 48000, AUDIO_FORMAT_PCM_16_BIT, AUDIO_CHANNEL_IN_STEREO);
     ASSERT_NE(nullptr, captureA);
-    EXPECT_EQ(OK, captureA->create()) << "record creation failed";
+    ASSERT_EQ(OK, captureA->create()) << "record creation failed";
     sp<OnAudioDeviceUpdateNotifier> cbCaptureA = sp<OnAudioDeviceUpdateNotifier>::make();
     EXPECT_EQ(OK, captureA->getAudioRecordHandle()->addAudioDeviceCallback(cbCaptureA));
 
@@ -199,7 +199,7 @@
             AUDIO_SOURCE_REMOTE_SUBMIX, 48000, AUDIO_FORMAT_PCM_16_BIT, AUDIO_CHANNEL_IN_STEREO,
             AUDIO_INPUT_FLAG_NONE, AUDIO_SESSION_ALLOCATE, AudioRecord::TRANSFER_CALLBACK, &attr);
     ASSERT_NE(nullptr, captureB);
-    EXPECT_EQ(OK, captureB->create()) << "record creation failed";
+    ASSERT_EQ(OK, captureB->create()) << "record creation failed";
     sp<OnAudioDeviceUpdateNotifier> cbCaptureB = sp<OnAudioDeviceUpdateNotifier>::make();
     EXPECT_EQ(OK, captureB->getAudioRecordHandle()->addAudioDeviceCallback(cbCaptureB));
 
diff --git a/media/libeffects/visualizer/aidl/VisualizerContext.cpp b/media/libeffects/visualizer/aidl/VisualizerContext.cpp
index 5d0d08d..a1726ad 100644
--- a/media/libeffects/visualizer/aidl/VisualizerContext.cpp
+++ b/media/libeffects/visualizer/aidl/VisualizerContext.cpp
@@ -223,8 +223,7 @@
         deltaSamples = kMaxCaptureBufSize;
     }
 
-    int32_t capturePoint;
-    //capturePoint = (int32_t)mCaptureIdx - deltaSamples;
+    int32_t capturePoint, captureSamples = mCaptureSamples;
     __builtin_sub_overflow((int32_t) mCaptureIdx, deltaSamples, &capturePoint);
     // a negative capturePoint means we wrap the buffer.
     if (capturePoint < 0) {
@@ -232,13 +231,14 @@
         if (size > mCaptureSamples) {
             size = mCaptureSamples;
         }
+        // first part of two stages copy, capture to the end of buffer and reset the size/point
         result.insert(result.end(), &mCaptureBuf[kMaxCaptureBufSize + capturePoint],
                         &mCaptureBuf[kMaxCaptureBufSize + capturePoint + size]);
-        mCaptureSamples -= size;
+        captureSamples -= size;
         capturePoint = 0;
     }
     result.insert(result.end(), &mCaptureBuf[capturePoint],
-                    &mCaptureBuf[capturePoint + mCaptureSamples]);
+                  &mCaptureBuf[capturePoint + captureSamples]);
     mLastCaptureIdx = mCaptureIdx;
     return result;
 }
diff --git a/media/libmediametrics/include/MediaMetricsConstants.h b/media/libmediametrics/include/MediaMetricsConstants.h
index f80a467..26aa375 100644
--- a/media/libmediametrics/include/MediaMetricsConstants.h
+++ b/media/libmediametrics/include/MediaMetricsConstants.h
@@ -184,6 +184,7 @@
 #define AMEDIAMETRICS_PROP_PLAYERIID      "playerIId"      // int32 (-1 invalid/unset IID)
 #define AMEDIAMETRICS_PROP_ROUTEDDEVICEID "routedDeviceId" // int32
 #define AMEDIAMETRICS_PROP_SAMPLERATE     "sampleRate"     // int32
+#define AMEDIAMETRICS_PROP_SAMPLERATECLIENT "sampleRateClient" // int32
 #define AMEDIAMETRICS_PROP_SAMPLERATEHARDWARE "sampleRateHardware" // int32
 #define AMEDIAMETRICS_PROP_SELECTEDDEVICEID "selectedDeviceId" // int32
 #define AMEDIAMETRICS_PROP_SELECTEDMICDIRECTION "selectedMicDirection" // int32
diff --git a/media/libmediaplayerservice/MediaPlayerService.cpp b/media/libmediaplayerservice/MediaPlayerService.cpp
index 73c3390..2e1fdcf 100644
--- a/media/libmediaplayerservice/MediaPlayerService.cpp
+++ b/media/libmediaplayerservice/MediaPlayerService.cpp
@@ -2627,6 +2627,16 @@
     Mutex::Autolock lock(mLock);
     ALOGV("AudioOutput::applyVolumeShaper");
 
+    if (configuration == nullptr) {
+        ALOGE("AudioOutput::applyVolumeShaper Null configuration parameter");
+        return VolumeShaper::Status(BAD_VALUE);
+    }
+
+    if (operation == nullptr) {
+        ALOGE("AudioOutput::applyVolumeShaper Null operation parameter");
+        return VolumeShaper::Status(BAD_VALUE);
+    }
+
     mVolumeHandler->setIdIfNecessary(configuration);
 
     VolumeShaper::Status status;
diff --git a/media/libstagefright/MediaCodec.cpp b/media/libstagefright/MediaCodec.cpp
index 28d554f..a0d56f8 100644
--- a/media/libstagefright/MediaCodec.cpp
+++ b/media/libstagefright/MediaCodec.cpp
@@ -6183,7 +6183,9 @@
             // presentation timestamp is used instead, which almost certainly occurs in the past,
             // since it's almost always a zero-based offset from the start of the stream. In these
             // scenarios, we expect the frame to be rendered with no delay.
-            int64_t delayUs = noRenderTime ? 0 : renderTimeNs / 1000 - ALooper::GetNowUs();
+            int64_t nowUs = ALooper::GetNowUs();
+            int64_t renderTimeUs = renderTimeNs / 1000;
+            int64_t delayUs = renderTimeUs < nowUs ? 0 : renderTimeUs - nowUs;
             delayUs += 100 * 1000; /* 100ms in microseconds */
             status_t err =
                     mMsgPollForRenderedBuffers->postUnique(/* token= */ mMsgPollForRenderedBuffers,
diff --git a/media/mtp/MtpPacket.cpp b/media/mtp/MtpPacket.cpp
index f069a83..5faaac2 100644
--- a/media/mtp/MtpPacket.cpp
+++ b/media/mtp/MtpPacket.cpp
@@ -92,24 +92,46 @@
 }
 
 uint16_t MtpPacket::getUInt16(int offset) const {
-    return ((uint16_t)mBuffer[offset + 1] << 8) | (uint16_t)mBuffer[offset];
+    if ((unsigned long)(offset+2) <= mBufferSize) {
+        return ((uint16_t)mBuffer[offset + 1] << 8) | (uint16_t)mBuffer[offset];
+    }
+    else {
+        ALOGE("offset for buffer read is greater than buffer size!");
+        abort();
+    }
 }
 
 uint32_t MtpPacket::getUInt32(int offset) const {
-    return ((uint32_t)mBuffer[offset + 3] << 24) | ((uint32_t)mBuffer[offset + 2] << 16) |
-           ((uint32_t)mBuffer[offset + 1] << 8)  | (uint32_t)mBuffer[offset];
+    if ((unsigned long)(offset+4) <= mBufferSize) {
+        return ((uint32_t)mBuffer[offset + 3] << 24) | ((uint32_t)mBuffer[offset + 2] << 16) |
+               ((uint32_t)mBuffer[offset + 1] << 8)  | (uint32_t)mBuffer[offset];
+    }
+    else {
+        ALOGE("offset for buffer read is greater than buffer size!");
+        abort();
+    }
 }
 
 void MtpPacket::putUInt16(int offset, uint16_t value) {
-    mBuffer[offset++] = (uint8_t)(value & 0xFF);
-    mBuffer[offset++] = (uint8_t)((value >> 8) & 0xFF);
+    if ((unsigned long)(offset+2) <= mBufferSize) {
+        mBuffer[offset++] = (uint8_t)(value & 0xFF);
+        mBuffer[offset++] = (uint8_t)((value >> 8) & 0xFF);
+    }
+    else {
+        ALOGE("offset for buffer write is greater than buffer size!");
+    }
 }
 
 void MtpPacket::putUInt32(int offset, uint32_t value) {
-    mBuffer[offset++] = (uint8_t)(value & 0xFF);
-    mBuffer[offset++] = (uint8_t)((value >> 8) & 0xFF);
-    mBuffer[offset++] = (uint8_t)((value >> 16) & 0xFF);
-    mBuffer[offset++] = (uint8_t)((value >> 24) & 0xFF);
+    if ((unsigned long)(offset+4) <= mBufferSize) {
+        mBuffer[offset++] = (uint8_t)(value & 0xFF);
+        mBuffer[offset++] = (uint8_t)((value >> 8) & 0xFF);
+        mBuffer[offset++] = (uint8_t)((value >> 16) & 0xFF);
+        mBuffer[offset++] = (uint8_t)((value >> 24) & 0xFF);
+    }
+    else {
+        ALOGE("offset for buffer write is greater than buffer size!");
+    }
 }
 
 uint16_t MtpPacket::getContainerCode() const {
diff --git a/services/audioflinger/AudioFlinger.cpp b/services/audioflinger/AudioFlinger.cpp
index 0f4fedc..5929969 100644
--- a/services/audioflinger/AudioFlinger.cpp
+++ b/services/audioflinger/AudioFlinger.cpp
@@ -328,7 +328,6 @@
       mTotalMemory(0),
       mClientSharedHeapSize(kMinimumClientSharedHeapSizeBytes),
       mGlobalEffectEnableTime(0),
-      mPatchPanel(this),
       mPatchCommandThread(sp<PatchCommandThread>::make()),
       mDeviceEffectManager(sp<DeviceEffectManager>::make(*this)),
       mMelReporter(sp<MelReporter>::make(*this)),
@@ -433,8 +432,8 @@
     for (const auto& [trackId, secondaryOutputs] : trackSecondaryOutputs) {
         size_t i = 0;
         for (; i < mPlaybackThreads.size(); ++i) {
-            PlaybackThread *thread = mPlaybackThreads.valueAt(i).get();
-            Mutex::Autolock _tl(thread->mLock);
+            IAfPlaybackThread* thread = mPlaybackThreads.valueAt(i).get();
+            Mutex::Autolock _tl(thread->mutex());
             sp<IAfTrack> track = thread->getTrackById_l(trackId);
             if (track != nullptr) {
                 ALOGD("%s trackId: %u", __func__, trackId);
@@ -678,9 +677,9 @@
 
     // at this stage, a MmapThread was created when openOutput() or openInput() was called by
     // audio policy manager and we can retrieve it
-    sp<MmapThread> thread = mMmapThreads.valueFor(io);
+    const sp<IAfMmapThread> thread = mMmapThreads.valueFor(io);
     if (thread != 0) {
-        interface = new MmapThreadHandle(thread);
+        interface = IAfMmapThread::createMmapStreamInterfaceAdapter(thread);
         thread->configure(&localAttr, streamType, actualSessionId, callback, *deviceId, portId);
         *handle = portId;
         *sessionId = actualSessionId;
@@ -934,7 +933,7 @@
             dev->dump(fd, args);
         }
 
-        mPatchPanel.dump(fd);
+        mPatchPanel->dump(fd);
 
         mDeviceEffectManager->dump(fd);
 
@@ -1191,7 +1190,7 @@
 
     {
         Mutex::Autolock _l(mLock);
-        PlaybackThread *thread = checkPlaybackThread_l(output.outputId);
+        IAfPlaybackThread* thread = checkPlaybackThread_l(output.outputId);
         if (thread == NULL) {
             ALOGE("no playback thread found for output handle %d", output.outputId);
             lStatus = BAD_VALUE;
@@ -1200,14 +1199,14 @@
 
         client = registerPid(clientPid);
 
-        PlaybackThread *effectThread = NULL;
+        IAfPlaybackThread* effectThread = nullptr;
         // check if an effect chain with the same session ID is present on another
         // output thread and move it here.
         for (size_t i = 0; i < mPlaybackThreads.size(); i++) {
-            sp<PlaybackThread> t = mPlaybackThreads.valueAt(i);
+            sp<IAfPlaybackThread> t = mPlaybackThreads.valueAt(i);
             if (mPlaybackThreads.keyAt(i) != output.outputId) {
                 uint32_t sessions = t->hasAudioSession(sessionId);
-                if (sessions & ThreadBase::EFFECT_SESSION) {
+                if (sessions & IAfThreadBase::EFFECT_SESSION) {
                     effectThread = t.get();
                     break;
                 }
@@ -1242,7 +1241,7 @@
 
         if (lStatus == NO_ERROR) {
             // no risk of deadlock because AudioFlinger::mLock is held
-            Mutex::Autolock _dl(thread->mLock);
+            Mutex::Autolock _dl(thread->mutex());
             // Connect secondary outputs. Failure on a secondary output must not imped the primary
             // Any secondary output setup failure will lead to a desync between the AP and AF until
             // the track is destroyed.
@@ -1250,7 +1249,7 @@
             // move effect chain to this output thread if an effect on same session was waiting
             // for a track to be created
             if (effectThread != nullptr) {
-                Mutex::Autolock _sl(effectThread->mLock);
+                Mutex::Autolock _sl(effectThread->mutex());
                 if (moveEffectChain_l(sessionId, effectThread, thread) == NO_ERROR) {
                     effectThreadId = thread->id();
                     effectIds = thread->getEffectIds_l(sessionId);
@@ -1310,7 +1309,7 @@
 uint32_t AudioFlinger::sampleRate(audio_io_handle_t ioHandle) const
 {
     Mutex::Autolock _l(mLock);
-    ThreadBase *thread = checkThread_l(ioHandle);
+    IAfThreadBase* const thread = checkThread_l(ioHandle);
     if (thread == NULL) {
         ALOGW("sampleRate() unknown thread %d", ioHandle);
         return 0;
@@ -1321,7 +1320,7 @@
 audio_format_t AudioFlinger::format(audio_io_handle_t output) const
 {
     Mutex::Autolock _l(mLock);
-    PlaybackThread *thread = checkPlaybackThread_l(output);
+    IAfPlaybackThread* const thread = checkPlaybackThread_l(output);
     if (thread == NULL) {
         ALOGW("format() unknown thread %d", output);
         return AUDIO_FORMAT_INVALID;
@@ -1332,7 +1331,7 @@
 size_t AudioFlinger::frameCount(audio_io_handle_t ioHandle) const
 {
     Mutex::Autolock _l(mLock);
-    ThreadBase *thread = checkThread_l(ioHandle);
+    IAfThreadBase* const thread = checkThread_l(ioHandle);
     if (thread == NULL) {
         ALOGW("frameCount() unknown thread %d", ioHandle);
         return 0;
@@ -1345,7 +1344,7 @@
 size_t AudioFlinger::frameCountHAL(audio_io_handle_t ioHandle) const
 {
     Mutex::Autolock _l(mLock);
-    ThreadBase *thread = checkThread_l(ioHandle);
+    IAfThreadBase* const thread = checkThread_l(ioHandle);
     if (thread == NULL) {
         ALOGW("frameCountHAL() unknown thread %d", ioHandle);
         return 0;
@@ -1356,7 +1355,7 @@
 uint32_t AudioFlinger::latency(audio_io_handle_t output) const
 {
     Mutex::Autolock _l(mLock);
-    PlaybackThread *thread = checkPlaybackThread_l(output);
+    IAfPlaybackThread* const thread = checkPlaybackThread_l(output);
     if (thread == NULL) {
         ALOGW("latency(): no playback thread found for output handle %d", output);
         return 0;
@@ -1585,7 +1584,7 @@
     // assigned to HALs which do not have master mute support will apply master mute
     // during the mix operation.  Threads with HALs which do support master mute
     // will simply ignore the setting.
-    Vector<VolumeInterface *> volumeInterfaces = getAllVolumeInterfaces_l();
+    std::vector<sp<VolumeInterface>> volumeInterfaces = getAllVolumeInterfaces_l();
     for (size_t i = 0; i < volumeInterfaces.size(); i++) {
         volumeInterfaces[i]->setMasterMute(muted);
     }
@@ -1661,7 +1660,7 @@
                         "AUDIO_STREAM_PATCH must have full scale volume");
 
     AutoMutex lock(mLock);
-    VolumeInterface *volumeInterface = getVolumeInterface_l(output);
+    sp<VolumeInterface> volumeInterface = getVolumeInterface_l(output);
     if (volumeInterface == NULL) {
         return BAD_VALUE;
     }
@@ -1676,7 +1675,7 @@
         return BAD_VALUE;
     }
     AutoMutex lock(mLock);
-    PlaybackThread *thread = checkPlaybackThread_l(output);
+    IAfPlaybackThread* const thread = checkPlaybackThread_l(output);
     if (thread == nullptr) {
         return BAD_VALUE;
     }
@@ -1689,7 +1688,7 @@
         return BAD_VALUE;
     }
     AutoMutex lock(mLock);
-    PlaybackThread *thread = checkPlaybackThread_l(output);
+    IAfPlaybackThread* const thread = checkPlaybackThread_l(output);
     if (thread == nullptr) {
         return BAD_VALUE;
     }
@@ -1764,7 +1763,7 @@
 
     AutoMutex lock(mLock);
     mStreamTypes[stream].mute = muted;
-    Vector<VolumeInterface *> volumeInterfaces = getAllVolumeInterfaces_l();
+    std::vector<sp<VolumeInterface>> volumeInterfaces = getAllVolumeInterfaces_l();
     for (size_t i = 0; i < volumeInterfaces.size(); i++) {
         volumeInterfaces[i]->setStreamMute(stream, muted);
     }
@@ -1783,7 +1782,7 @@
     }
 
     AutoMutex lock(mLock);
-    VolumeInterface *volumeInterface = getVolumeInterface_l(output);
+    sp<VolumeInterface> volumeInterface = getVolumeInterface_l(output);
     if (volumeInterface == NULL) {
         return 0.0f;
     }
@@ -1820,14 +1819,15 @@
 // forwardAudioHwSyncToDownstreamPatches_l() must be called with AudioFlinger::mLock held
 void AudioFlinger::forwardParametersToDownstreamPatches_l(
         audio_io_handle_t upStream, const String8& keyValuePairs,
-        const std::function<bool(const sp<PlaybackThread>&)>& useThread)
+        const std::function<bool(const sp<IAfPlaybackThread>&)>& useThread)
 {
-    std::vector<PatchPanel::SoftwarePatch> swPatches;
-    if (mPatchPanel.getDownstreamSoftwarePatches(upStream, &swPatches) != OK) return;
+    std::vector<SoftwarePatch> swPatches;
+    if (mPatchPanel->getDownstreamSoftwarePatches(upStream, &swPatches) != OK) return;
     ALOGV_IF(!swPatches.empty(), "%s found %zu downstream patches for stream ID %d",
             __func__, swPatches.size(), upStream);
     for (const auto& swPatch : swPatches) {
-        sp<PlaybackThread> downStream = checkPlaybackThread_l(swPatch.getPlaybackThreadHandle());
+        const sp<IAfPlaybackThread> downStream =
+                checkPlaybackThread_l(swPatch.getPlaybackThreadHandle());
         if (downStream != NULL && (useThread == nullptr || useThread(downStream))) {
             downStream->setParameters(keyValuePairs);
         }
@@ -1839,7 +1839,7 @@
                                              const std::set<audio_io_handle_t>& streams)
 {
     for (const audio_io_handle_t stream : streams) {
-        PlaybackThread *playbackThread = checkPlaybackThread_l(stream);
+        IAfPlaybackThread* const playbackThread = checkPlaybackThread_l(stream);
         if (playbackThread == nullptr || !playbackThread->isMsdDevice()) {
             continue;
         }
@@ -1962,7 +1962,7 @@
 
     // hold a strong ref on thread in case closeOutput() or closeInput() is called
     // and the thread is exited once the lock is released
-    sp<ThreadBase> thread;
+    sp<IAfThreadBase> thread;
     {
         Mutex::Autolock _l(mLock);
         thread = checkPlaybackThread_l(ioHandle);
@@ -2011,11 +2011,11 @@
         return out_s8;
     }
 
-    ThreadBase *thread = (ThreadBase *)checkPlaybackThread_l(ioHandle);
+    IAfThreadBase* thread = checkPlaybackThread_l(ioHandle);
     if (thread == NULL) {
-        thread = (ThreadBase *)checkRecordThread_l(ioHandle);
+        thread = checkRecordThread_l(ioHandle);
         if (thread == NULL) {
-            thread = (ThreadBase *)checkMmapThread_l(ioHandle);
+            thread = checkMmapThread_l(ioHandle);
             if (thread == NULL) {
                 return String8("");
             }
@@ -2111,7 +2111,7 @@
 {
     Mutex::Autolock _l(mLock);
 
-    RecordThread *recordThread = checkRecordThread_l(ioHandle);
+    IAfRecordThread* const recordThread = checkRecordThread_l(ioHandle);
     if (recordThread != NULL) {
         return recordThread->getInputFramesLost();
     }
@@ -2151,7 +2151,7 @@
 {
     Mutex::Autolock _l(mLock);
 
-    PlaybackThread *playbackThread = checkPlaybackThread_l(output);
+    IAfPlaybackThread* const playbackThread = checkPlaybackThread_l(output);
     if (playbackThread != NULL) {
         return playbackThread->getRenderPosition(halFrames, dspFrames);
     }
@@ -2277,10 +2277,10 @@
 }
 
 // getEffectThread_l() must be called with AudioFlinger::mLock held
-sp<AudioFlinger::ThreadBase> AudioFlinger::getEffectThread_l(audio_session_t sessionId,
+sp<IAfThreadBase> AudioFlinger::getEffectThread_l(audio_session_t sessionId,
         int effectId)
 {
-    sp<ThreadBase> thread;
+    sp<IAfThreadBase> thread;
 
     for (size_t i = 0; i < mPlaybackThreads.size(); i++) {
         if (mPlaybackThreads.valueAt(i)->getEffect(sessionId, effectId) != 0) {
@@ -2483,7 +2483,7 @@
 
     {
         Mutex::Autolock _l(mLock);
-        RecordThread *thread = checkRecordThread_l(output.inputId);
+        IAfRecordThread* const thread = checkRecordThread_l(output.inputId);
         if (thread == NULL) {
             ALOGW("createRecord() checkRecordThread_l failed, input handle %d", output.inputId);
             lStatus = FAILED_TRANSACTION;
@@ -2539,7 +2539,7 @@
         // session and move it to this thread.
         sp<IAfEffectChain> chain = getOrphanEffectChain_l(sessionId);
         if (chain != 0) {
-            Mutex::Autolock _l2(thread->mLock);
+            Mutex::Autolock _l2(thread->mutex());
             thread->addEffectChain_l(chain);
         }
         break;
@@ -2741,14 +2741,14 @@
 uint32_t AudioFlinger::getPrimaryOutputSamplingRate()
 {
     Mutex::Autolock _l(mLock);
-    PlaybackThread *thread = fastPlaybackThread_l();
+    IAfPlaybackThread* const thread = fastPlaybackThread_l();
     return thread != NULL ? thread->sampleRate() : 0;
 }
 
 size_t AudioFlinger::getPrimaryOutputFrameCount()
 {
     Mutex::Autolock _l(mLock);
-    PlaybackThread *thread = fastPlaybackThread_l();
+    IAfPlaybackThread* const thread = fastPlaybackThread_l();
     return thread != NULL ? thread->frameCountHAL() : 0;
 }
 
@@ -2873,15 +2873,15 @@
     mHwAvSyncIds.add(sessionId, value);
 
     for (size_t i = 0; i < mPlaybackThreads.size(); i++) {
-        sp<PlaybackThread> thread = mPlaybackThreads.valueAt(i);
+        const sp<IAfPlaybackThread> thread = mPlaybackThreads.valueAt(i);
         uint32_t sessions = thread->hasAudioSession(sessionId);
-        if (sessions & ThreadBase::TRACK_SESSION) {
+        if (sessions & IAfThreadBase::TRACK_SESSION) {
             AudioParameter param = AudioParameter();
             param.addInt(String8(AudioParameter::keyStreamHwAvSync), value);
             String8 keyValuePairs = param.toString();
             thread->setParameters(keyValuePairs);
             forwardParametersToDownstreamPatches_l(thread->id(), keyValuePairs,
-                    [](const sp<PlaybackThread>& thread) { return thread->usesHwAvSync(); });
+                    [](const sp<IAfPlaybackThread>& thread) { return thread->usesHwAvSync(); });
             break;
         }
     }
@@ -2900,15 +2900,15 @@
     }
     mSystemReady = true;
     for (size_t i = 0; i < mPlaybackThreads.size(); i++) {
-        ThreadBase *thread = (ThreadBase *)mPlaybackThreads.valueAt(i).get();
+        IAfThreadBase* const thread = mPlaybackThreads.valueAt(i).get();
         thread->systemReady();
     }
     for (size_t i = 0; i < mRecordThreads.size(); i++) {
-        ThreadBase *thread = (ThreadBase *)mRecordThreads.valueAt(i).get();
+        IAfThreadBase* const thread = mRecordThreads.valueAt(i).get();
         thread->systemReady();
     }
     for (size_t i = 0; i < mMmapThreads.size(); i++) {
-        ThreadBase *thread = (ThreadBase *)mMmapThreads.valueAt(i).get();
+        IAfThreadBase* const thread = mMmapThreads.valueAt(i).get();
         thread->systemReady();
     }
 
@@ -2960,7 +2960,8 @@
 }
 
 // setAudioHwSyncForSession_l() must be called with AudioFlinger::mLock held
-void AudioFlinger::setAudioHwSyncForSession_l(PlaybackThread *thread, audio_session_t sessionId)
+void AudioFlinger::setAudioHwSyncForSession_l(
+        IAfPlaybackThread* const thread, audio_session_t sessionId)
 {
     ssize_t index = mHwAvSyncIds.indexOfKey(sessionId);
     if (index >= 0) {
@@ -2971,7 +2972,7 @@
         String8 keyValuePairs = param.toString();
         thread->setParameters(keyValuePairs);
         forwardParametersToDownstreamPatches_l(thread->id(), keyValuePairs,
-                [](const sp<PlaybackThread>& thread) { return thread->usesHwAvSync(); });
+                [](const sp<IAfPlaybackThread>& thread) { return thread->usesHwAvSync(); });
     }
 }
 
@@ -2979,7 +2980,7 @@
 // ----------------------------------------------------------------------------
 
 
-sp<AudioFlinger::ThreadBase> AudioFlinger::openOutput_l(audio_module_handle_t module,
+sp<IAfThreadBase> AudioFlinger::openOutput_l(audio_module_handle_t module,
                                                         audio_io_handle_t *output,
                                                         audio_config_t *halConfig,
                                                         audio_config_base_t *mixerConfig,
@@ -3037,43 +3038,45 @@
 
     if (status == NO_ERROR) {
         if (flags & AUDIO_OUTPUT_FLAG_MMAP_NOIRQ) {
-            sp<MmapPlaybackThread> thread =
-                    new MmapPlaybackThread(this, *output, outHwDev, outputStream, mSystemReady);
+            const sp<IAfMmapPlaybackThread> thread = IAfMmapPlaybackThread::create(
+                    this, *output, outHwDev, outputStream, mSystemReady);
             mMmapThreads.add(*output, thread);
             ALOGV("openOutput_l() created mmap playback thread: ID %d thread %p",
                   *output, thread.get());
             return thread;
         } else {
-            sp<PlaybackThread> thread;
+            sp<IAfPlaybackThread> thread;
             if (flags & AUDIO_OUTPUT_FLAG_BIT_PERFECT) {
-                thread = sp<BitPerfectThread>::make(this, outputStream, *output, mSystemReady);
+                thread = IAfPlaybackThread::createBitPerfectThread(
+                        this, outputStream, *output, mSystemReady);
                 ALOGV("%s() created bit-perfect output: ID %d thread %p",
                       __func__, *output, thread.get());
             } else if (flags & AUDIO_OUTPUT_FLAG_SPATIALIZER) {
-                thread = new SpatializerThread(this, outputStream, *output,
+                thread = IAfPlaybackThread::createSpatializerThread(this, outputStream, *output,
                                                     mSystemReady, mixerConfig);
                 ALOGV("openOutput_l() created spatializer output: ID %d thread %p",
                       *output, thread.get());
             } else if (flags & AUDIO_OUTPUT_FLAG_COMPRESS_OFFLOAD) {
-                thread = new OffloadThread(this, outputStream, *output,
+                thread = IAfPlaybackThread::createOffloadThread(this, outputStream, *output,
                         mSystemReady, halConfig->offload_info);
                 ALOGV("openOutput_l() created offload output: ID %d thread %p",
                       *output, thread.get());
             } else if ((flags & AUDIO_OUTPUT_FLAG_DIRECT)
                     || !isValidPcmSinkFormat(halConfig->format)
                     || !isValidPcmSinkChannelMask(halConfig->channel_mask)) {
-                thread = new DirectOutputThread(this, outputStream, *output,
+                thread = IAfPlaybackThread::createDirectOutputThread(this, outputStream, *output,
                         mSystemReady, halConfig->offload_info);
                 ALOGV("openOutput_l() created direct output: ID %d thread %p",
                       *output, thread.get());
             } else {
-                thread = new MixerThread(this, outputStream, *output, mSystemReady);
+                thread = IAfPlaybackThread::createMixerThread(
+                        this, outputStream, *output, mSystemReady);
                 ALOGV("openOutput_l() created mixer output: ID %d thread %p",
                       *output, thread.get());
             }
             mPlaybackThreads.add(*output, thread);
             struct audio_patch patch;
-            mPatchPanel.notifyStreamOpened(outHwDev, *output, &patch);
+            mPatchPanel->notifyStreamOpened(outHwDev, *output, &patch);
             if (thread->isMsdDevice()) {
                 thread->setDownStreamPatch(&patch);
             }
@@ -3119,12 +3122,12 @@
 
     Mutex::Autolock _l(mLock);
 
-    sp<ThreadBase> thread = openOutput_l(module, &output, &halConfig,
+    const sp<IAfThreadBase> thread = openOutput_l(module, &output, &halConfig,
             &mixerConfig, deviceType, address, flags);
     if (thread != 0) {
         uint32_t latencyMs = 0;
         if ((flags & AUDIO_OUTPUT_FLAG_MMAP_NOIRQ) == 0) {
-            PlaybackThread *playbackThread = (PlaybackThread *)thread.get();
+            const auto playbackThread = thread->asIAfPlaybackThread();
             latencyMs = playbackThread->latency();
 
             // notify client processes of the new output creation
@@ -3142,8 +3145,7 @@
                 mHardwareStatus = AUDIO_HW_IDLE;
             }
         } else {
-            MmapThread *mmapThread = (MmapThread *)thread.get();
-            mmapThread->ioConfigChanged(AUDIO_OUTPUT_OPENED);
+            thread->ioConfigChanged(AUDIO_OUTPUT_OPENED);
         }
         response->output = VALUE_OR_RETURN_STATUS(legacy2aidl_audio_io_handle_t_int32_t(output));
         response->config = VALUE_OR_RETURN_STATUS(
@@ -3161,8 +3163,8 @@
         audio_io_handle_t output2)
 {
     Mutex::Autolock _l(mLock);
-    MixerThread *thread1 = checkMixerThread_l(output1);
-    MixerThread *thread2 = checkMixerThread_l(output2);
+    IAfPlaybackThread* const thread1 = checkMixerThread_l(output1);
+    IAfPlaybackThread* const thread2 = checkMixerThread_l(output2);
 
     if (thread1 == NULL || thread2 == NULL) {
         ALOGW("openDuplicateOutput() wrong output mixer type for output %d or %d", output1,
@@ -3171,7 +3173,8 @@
     }
 
     audio_io_handle_t id = nextUniqueId(AUDIO_UNIQUE_ID_USE_OUTPUT);
-    DuplicatingThread *thread = new DuplicatingThread(this, thread1, id, mSystemReady);
+    const sp<IAfDuplicatingThread> thread = IAfDuplicatingThread::create(
+            this, thread1, id, mSystemReady);
     thread->addOutputTrack(thread2);
     mPlaybackThreads.add(id, thread);
     // notify client processes of the new output creation
@@ -3188,8 +3191,8 @@
 {
     // keep strong reference on the playback thread so that
     // it is not destroyed while exit() is executed
-    sp<PlaybackThread> playbackThread;
-    sp<MmapPlaybackThread> mmapThread;
+    sp<IAfPlaybackThread> playbackThread;
+    sp<IAfMmapPlaybackThread> mmapThread;
     {
         Mutex::Autolock _l(mLock);
         playbackThread = checkPlaybackThread_l(output);
@@ -3198,12 +3201,12 @@
 
             dumpToThreadLog_l(playbackThread);
 
-            if (playbackThread->type() == ThreadBase::MIXER) {
+            if (playbackThread->type() == IAfThreadBase::MIXER) {
                 for (size_t i = 0; i < mPlaybackThreads.size(); i++) {
                     if (mPlaybackThreads.valueAt(i)->isDuplicating()) {
-                        DuplicatingThread *dupThread =
-                                (DuplicatingThread *)mPlaybackThreads.valueAt(i).get();
-                        dupThread->removeOutputTrack((MixerThread *)playbackThread.get());
+                        IAfDuplicatingThread* const dupThread =
+                                mPlaybackThreads.valueAt(i)->asIAfDuplicatingThread().get();
+                        dupThread->removeOutputTrack(playbackThread.get());
                     }
                 }
             }
@@ -3212,11 +3215,12 @@
             mPlaybackThreads.removeItem(output);
             // save all effects to the default thread
             if (mPlaybackThreads.size()) {
-                PlaybackThread *dstThread = checkPlaybackThread_l(mPlaybackThreads.keyAt(0));
+                IAfPlaybackThread* const dstThread =
+                        checkPlaybackThread_l(mPlaybackThreads.keyAt(0));
                 if (dstThread != NULL) {
                     // audioflinger lock is held so order of thread lock acquisition doesn't matter
-                    Mutex::Autolock _dl(dstThread->mLock);
-                    Mutex::Autolock _sl(playbackThread->mLock);
+                    Mutex::Autolock _dl(dstThread->mutex());
+                    Mutex::Autolock _sl(playbackThread->mutex());
                     Vector<sp<IAfEffectChain>> effectChains = playbackThread->getEffectChains_l();
                     for (size_t i = 0; i < effectChains.size(); i ++) {
                         moveEffectChain_l(effectChains[i]->sessionId(), playbackThread.get(),
@@ -3225,7 +3229,8 @@
                 }
             }
         } else {
-            mmapThread = (MmapPlaybackThread *)checkMmapThread_l(output);
+            const sp<IAfMmapThread> mt = checkMmapThread_l(output);
+            mmapThread = mt ? mt->asIAfMmapPlaybackThread().get() : nullptr;
             if (mmapThread == 0) {
                 return BAD_VALUE;
             }
@@ -3234,10 +3239,10 @@
             ALOGD("closing mmapThread %p", mmapThread.get());
         }
         ioConfigChanged(AUDIO_OUTPUT_CLOSED, sp<AudioIoDescriptor>::make(output));
-        mPatchPanel.notifyStreamClosed(output);
+        mPatchPanel->notifyStreamClosed(output);
     }
     // The thread entity (active unit of execution) is no longer running here,
-    // but the ThreadBase container still exists.
+    // but the IAfThreadBase container still exists.
 
     if (playbackThread != 0) {
         playbackThread->exit();
@@ -3255,7 +3260,7 @@
     return NO_ERROR;
 }
 
-void AudioFlinger::closeOutputFinish(const sp<PlaybackThread>& thread)
+void AudioFlinger::closeOutputFinish(const sp<IAfPlaybackThread>& thread)
 {
     AudioStreamOut *out = thread->clearOutput();
     ALOG_ASSERT(out != NULL, "out shouldn't be NULL");
@@ -3263,9 +3268,9 @@
     delete out;
 }
 
-void AudioFlinger::closeThreadInternal_l(const sp<PlaybackThread>& thread)
+void AudioFlinger::closeThreadInternal_l(const sp<IAfPlaybackThread>& thread)
 {
-    mPlaybackThreads.removeItem(thread->mId);
+    mPlaybackThreads.removeItem(thread->id());
     thread->exit();
     closeOutputFinish(thread);
 }
@@ -3273,7 +3278,7 @@
 status_t AudioFlinger::suspendOutput(audio_io_handle_t output)
 {
     Mutex::Autolock _l(mLock);
-    PlaybackThread *thread = checkPlaybackThread_l(output);
+    IAfPlaybackThread* const thread = checkPlaybackThread_l(output);
 
     if (thread == NULL) {
         return BAD_VALUE;
@@ -3288,7 +3293,7 @@
 status_t AudioFlinger::restoreOutput(audio_io_handle_t output)
 {
     Mutex::Autolock _l(mLock);
-    PlaybackThread *thread = checkPlaybackThread_l(output);
+    IAfPlaybackThread* const thread = checkPlaybackThread_l(output);
 
     if (thread == NULL) {
         return BAD_VALUE;
@@ -3317,7 +3322,7 @@
     audio_config_t config = VALUE_OR_RETURN_STATUS(
             aidl2legacy_AudioConfig_audio_config_t(request.config, true /*isInput*/));
 
-    sp<ThreadBase> thread = openInput_l(
+    const sp<IAfThreadBase> thread = openInput_l(
             VALUE_OR_RETURN_STATUS(aidl2legacy_int32_t_audio_module_handle_t(request.module)),
             &input,
             &config,
@@ -3341,7 +3346,7 @@
     return NO_INIT;
 }
 
-sp<AudioFlinger::ThreadBase> AudioFlinger::openInput_l(audio_module_handle_t module,
+sp<IAfThreadBase> AudioFlinger::openInput_l(audio_module_handle_t module,
                                                          audio_io_handle_t *input,
                                                          audio_config_t *config,
                                                          audio_devices_t devices,
@@ -3407,17 +3412,18 @@
     if (status == NO_ERROR && inStream != 0) {
         AudioStreamIn *inputStream = new AudioStreamIn(inHwDev, inStream, flags);
         if ((flags & AUDIO_INPUT_FLAG_MMAP_NOIRQ) != 0) {
-            sp<MmapCaptureThread> thread =
-                    new MmapCaptureThread(this, *input, inHwDev, inputStream, mSystemReady);
+            const sp<IAfMmapCaptureThread> thread =
+                    IAfMmapCaptureThread::create(this, *input, inHwDev, inputStream, mSystemReady);
             mMmapThreads.add(*input, thread);
             ALOGV("openInput_l() created mmap capture thread: ID %d thread %p", *input,
                     thread.get());
             return thread;
         } else {
             // Start record thread
-            // RecordThread requires both input and output device indication to forward to audio
-            // pre processing modules
-            sp<RecordThread> thread = new RecordThread(this, inputStream, *input, mSystemReady);
+            // IAfRecordThread requires both input and output device indication
+            // to forward to audio pre processing modules
+            const sp<IAfRecordThread> thread =
+                    IAfRecordThread::create(this, inputStream, *input, mSystemReady);
             mRecordThreads.add(*input, thread);
             ALOGV("openInput_l() created record thread: ID %d thread %p", *input, thread.get());
             return thread;
@@ -3437,8 +3443,8 @@
 {
     // keep strong reference on the record thread so that
     // it is not destroyed while exit() is executed
-    sp<RecordThread> recordThread;
-    sp<MmapCaptureThread> mmapThread;
+    sp<IAfRecordThread> recordThread;
+    sp<IAfMmapCaptureThread> mmapThread;
     {
         Mutex::Autolock _l(mLock);
         recordThread = checkRecordThread_l(input);
@@ -3453,8 +3459,8 @@
             // new capture on the same session
             sp<IAfEffectChain> chain;
             {
-                Mutex::Autolock _sl(recordThread->mLock);
-                Vector< sp<IAfEffectChain> > effectChains = recordThread->getEffectChains_l();
+                Mutex::Autolock _sl(recordThread->mutex());
+                const Vector<sp<IAfEffectChain>> effectChains = recordThread->getEffectChains_l();
                 // Note: maximum one chain per record thread
                 if (effectChains.size() != 0) {
                     chain = effectChains[0];
@@ -3466,12 +3472,12 @@
                 // creation of its replacement
                 size_t i;
                 for (i = 0; i < mRecordThreads.size(); i++) {
-                    sp<RecordThread> t = mRecordThreads.valueAt(i);
+                    const sp<IAfRecordThread> t = mRecordThreads.valueAt(i);
                     if (t == recordThread) {
                         continue;
                     }
                     if (t->hasAudioSession(chain->sessionId()) != 0) {
-                        Mutex::Autolock _l2(t->mLock);
+                        Mutex::Autolock _l2(t->mutex());
                         ALOGV("closeInput() found thread %d for effect session %d",
                               t->id(), chain->sessionId());
                         t->addEffectChain_l(chain);
@@ -3485,7 +3491,8 @@
             }
             mRecordThreads.removeItem(input);
         } else {
-            mmapThread = (MmapCaptureThread *)checkMmapThread_l(input);
+            const sp<IAfMmapThread> mt = checkMmapThread_l(input);
+            mmapThread = mt ? mt->asIAfMmapCaptureThread().get() : nullptr;
             if (mmapThread == 0) {
                 return BAD_VALUE;
             }
@@ -3508,7 +3515,7 @@
     return NO_ERROR;
 }
 
-void AudioFlinger::closeInputFinish(const sp<RecordThread>& thread)
+void AudioFlinger::closeInputFinish(const sp<IAfRecordThread>& thread)
 {
     thread->exit();
     AudioStreamIn *in = thread->clearInput();
@@ -3517,9 +3524,9 @@
     delete in;
 }
 
-void AudioFlinger::closeThreadInternal_l(const sp<RecordThread>& thread)
+void AudioFlinger::closeThreadInternal_l(const sp<IAfRecordThread>& thread)
 {
-    mRecordThreads.removeItem(thread->mId);
+    mRecordThreads.removeItem(thread->id());
     closeInputFinish(thread);
 }
 
@@ -3529,7 +3536,7 @@
 
     std::set<audio_port_handle_t> portIdSet(portIds.begin(), portIds.end());
     for (size_t i = 0; i < mPlaybackThreads.size(); i++) {
-        PlaybackThread *thread = mPlaybackThreads.valueAt(i).get();
+        IAfPlaybackThread* const thread = mPlaybackThreads.valueAt(i).get();
         thread->invalidateTracks(portIdSet);
         if (portIdSet.empty()) {
             return NO_ERROR;
@@ -3649,14 +3656,15 @@
 
     ALOGV("purging stale effects");
 
-    Vector< sp<IAfEffectChain> > chains;
+    Vector<sp<IAfEffectChain>> chains;
     std::vector< sp<IAfEffectModule> > removedEffects;
 
     for (size_t i = 0; i < mPlaybackThreads.size(); i++) {
-        sp<PlaybackThread> t = mPlaybackThreads.valueAt(i);
-        Mutex::Autolock _l(t->mLock);
-        for (size_t j = 0; j < t->mEffectChains.size(); j++) {
-            sp<IAfEffectChain> ec = t->mEffectChains[j];
+        sp<IAfPlaybackThread> t = mPlaybackThreads.valueAt(i);
+        Mutex::Autolock _l(t->mutex());
+        const Vector<sp<IAfEffectChain>> threadChains = t->getEffectChains_l();
+        for (size_t j = 0; j < threadChains.size(); j++) {
+            sp<IAfEffectChain> ec = threadChains[j];
             if (!audio_is_global_session(ec->sessionId())) {
                 chains.push(ec);
             }
@@ -3664,19 +3672,21 @@
     }
 
     for (size_t i = 0; i < mRecordThreads.size(); i++) {
-        sp<RecordThread> t = mRecordThreads.valueAt(i);
-        Mutex::Autolock _l(t->mLock);
-        for (size_t j = 0; j < t->mEffectChains.size(); j++) {
-            sp<IAfEffectChain> ec = t->mEffectChains[j];
+        sp<IAfRecordThread> t = mRecordThreads.valueAt(i);
+        Mutex::Autolock _l(t->mutex());
+        const Vector<sp<IAfEffectChain>> threadChains = t->getEffectChains_l();
+        for (size_t j = 0; j < threadChains.size(); j++) {
+            sp<IAfEffectChain> ec = threadChains[j];
             chains.push(ec);
         }
     }
 
     for (size_t i = 0; i < mMmapThreads.size(); i++) {
-        sp<MmapThread> t = mMmapThreads.valueAt(i);
-        Mutex::Autolock _l(t->mLock);
-        for (size_t j = 0; j < t->mEffectChains.size(); j++) {
-            sp<IAfEffectChain> ec = t->mEffectChains[j];
+        const sp<IAfMmapThread> t = mMmapThreads.valueAt(i);
+        Mutex::Autolock _l(t->mutex());
+        const Vector<sp<IAfEffectChain>> threadChains = t->getEffectChains_l();
+        for (size_t j = 0; j < threadChains.size(); j++) {
+            sp<IAfEffectChain> ec = threadChains[j];
             chains.push(ec);
         }
     }
@@ -3685,7 +3695,7 @@
          // clang-tidy suggests const ref
         sp<IAfEffectChain> ec = chains[i];  // NOLINT(performance-unnecessary-copy-initialization)
         int sessionid = ec->sessionId();
-        sp<ThreadBase> t = sp<ThreadBase>::cast(ec->thread().promote()); // TODO(b/288339104)
+        const auto t = ec->thread().promote();
         if (t == 0) {
             continue;
         }
@@ -3701,7 +3711,7 @@
             }
         }
         if (!found) {
-            Mutex::Autolock _l(t->mLock);
+            Mutex::Autolock _l(t->mutex());
             // remove all effects from the chain
             while (ec->numberOfEffects()) {
                 sp<IAfEffectModule> effect = ec->getEffectModule(0);
@@ -3754,7 +3764,7 @@
 }
 
 // dumpToThreadLog_l() must be called with AudioFlinger::mLock held
-void AudioFlinger::dumpToThreadLog_l(const sp<ThreadBase> &thread)
+void AudioFlinger::dumpToThreadLog_l(const sp<IAfThreadBase> &thread)
 {
     constexpr int THREAD_DUMP_TIMEOUT_MS = 2;
     audio_utils::FdToString fdToString("- ", THREAD_DUMP_TIMEOUT_MS);
@@ -3766,9 +3776,9 @@
 }
 
 // checkThread_l() must be called with AudioFlinger::mLock held
-AudioFlinger::ThreadBase *AudioFlinger::checkThread_l(audio_io_handle_t ioHandle) const
+IAfThreadBase* AudioFlinger::checkThread_l(audio_io_handle_t ioHandle) const
 {
-    ThreadBase *thread = checkMmapThread_l(ioHandle);
+    IAfThreadBase* thread = checkMmapThread_l(ioHandle);
     if (thread == 0) {
         switch (audio_unique_id_get_use(ioHandle)) {
         case AUDIO_UNIQUE_ID_USE_OUTPUT:
@@ -3785,13 +3795,13 @@
 }
 
 // checkOutputThread_l() must be called with AudioFlinger::mLock held
-sp<AudioFlinger::ThreadBase> AudioFlinger::checkOutputThread_l(audio_io_handle_t ioHandle) const
+sp<IAfThreadBase> AudioFlinger::checkOutputThread_l(audio_io_handle_t ioHandle) const
 {
     if (audio_unique_id_get_use(ioHandle) != AUDIO_UNIQUE_ID_USE_OUTPUT) {
         return nullptr;
     }
 
-    sp<AudioFlinger::ThreadBase> thread = mPlaybackThreads.valueFor(ioHandle);
+    sp<IAfThreadBase> thread = mPlaybackThreads.valueFor(ioHandle);
     if (thread == nullptr) {
         thread = mMmapThreads.valueFor(ioHandle);
     }
@@ -3799,41 +3809,41 @@
 }
 
 // checkPlaybackThread_l() must be called with AudioFlinger::mLock held
-AudioFlinger::PlaybackThread *AudioFlinger::checkPlaybackThread_l(audio_io_handle_t output) const
+IAfPlaybackThread* AudioFlinger::checkPlaybackThread_l(audio_io_handle_t output) const
 {
     return mPlaybackThreads.valueFor(output).get();
 }
 
 // checkMixerThread_l() must be called with AudioFlinger::mLock held
-AudioFlinger::MixerThread *AudioFlinger::checkMixerThread_l(audio_io_handle_t output) const
+IAfPlaybackThread* AudioFlinger::checkMixerThread_l(audio_io_handle_t output) const
 {
-    PlaybackThread *thread = checkPlaybackThread_l(output);
-    return thread != NULL && thread->type() != ThreadBase::DIRECT ? (MixerThread *) thread : NULL;
+    IAfPlaybackThread * const thread = checkPlaybackThread_l(output);
+    return thread != nullptr && thread->type() != IAfThreadBase::DIRECT ? thread : nullptr;
 }
 
 // checkRecordThread_l() must be called with AudioFlinger::mLock held
-AudioFlinger::RecordThread *AudioFlinger::checkRecordThread_l(audio_io_handle_t input) const
+IAfRecordThread* AudioFlinger::checkRecordThread_l(audio_io_handle_t input) const
 {
     return mRecordThreads.valueFor(input).get();
 }
 
 // checkMmapThread_l() must be called with AudioFlinger::mLock held
-AudioFlinger::MmapThread *AudioFlinger::checkMmapThread_l(audio_io_handle_t io) const
+IAfMmapThread* AudioFlinger::checkMmapThread_l(audio_io_handle_t io) const
 {
     return mMmapThreads.valueFor(io).get();
 }
 
 
 // checkPlaybackThread_l() must be called with AudioFlinger::mLock held
-AudioFlinger::VolumeInterface *AudioFlinger::getVolumeInterface_l(audio_io_handle_t output) const
+sp<VolumeInterface> AudioFlinger::getVolumeInterface_l(audio_io_handle_t output) const
 {
-    VolumeInterface *volumeInterface = mPlaybackThreads.valueFor(output).get();
+    sp<VolumeInterface> volumeInterface = mPlaybackThreads.valueFor(output).get();
     if (volumeInterface == nullptr) {
-        MmapThread *mmapThread = mMmapThreads.valueFor(output).get();
+        IAfMmapThread* const mmapThread = mMmapThreads.valueFor(output).get();
         if (mmapThread != nullptr) {
             if (mmapThread->isOutput()) {
-                MmapPlaybackThread *mmapPlaybackThread =
-                        static_cast<MmapPlaybackThread *>(mmapThread);
+                IAfMmapPlaybackThread* const mmapPlaybackThread =
+                        mmapThread->asIAfMmapPlaybackThread().get();
                 volumeInterface = mmapPlaybackThread;
             }
         }
@@ -3841,17 +3851,17 @@
     return volumeInterface;
 }
 
-Vector <AudioFlinger::VolumeInterface *> AudioFlinger::getAllVolumeInterfaces_l() const
+std::vector<sp<VolumeInterface>> AudioFlinger::getAllVolumeInterfaces_l() const
 {
-    Vector <VolumeInterface *> volumeInterfaces;
+    std::vector<sp<VolumeInterface>> volumeInterfaces;
     for (size_t i = 0; i < mPlaybackThreads.size(); i++) {
-        volumeInterfaces.add(mPlaybackThreads.valueAt(i).get());
+        volumeInterfaces.push_back(mPlaybackThreads.valueAt(i).get());
     }
     for (size_t i = 0; i < mMmapThreads.size(); i++) {
         if (mMmapThreads.valueAt(i)->isOutput()) {
-            MmapPlaybackThread *mmapPlaybackThread =
-                    static_cast<MmapPlaybackThread *>(mMmapThreads.valueAt(i).get());
-            volumeInterfaces.add(mmapPlaybackThread);
+            IAfMmapPlaybackThread* const mmapPlaybackThread =
+                    mMmapThreads.valueAt(i)->asIAfMmapPlaybackThread().get();
+            volumeInterfaces.push_back(mmapPlaybackThread);
         }
     }
     return volumeInterfaces;
@@ -3878,14 +3888,14 @@
     // TODO Use a floor after wraparound.  This may need a mutex.
 }
 
-AudioFlinger::PlaybackThread *AudioFlinger::primaryPlaybackThread_l() const
+IAfPlaybackThread* AudioFlinger::primaryPlaybackThread_l() const
 {
     AutoMutex lock(mHardwareLock);
     if (mPrimaryHardwareDev == nullptr) {
         return nullptr;
     }
     for (size_t i = 0; i < mPlaybackThreads.size(); i++) {
-        PlaybackThread *thread = mPlaybackThreads.valueAt(i).get();
+        IAfPlaybackThread* const thread = mPlaybackThreads.valueAt(i).get();
         if(thread->isDuplicating()) {
             continue;
         }
@@ -3899,7 +3909,7 @@
 
 DeviceTypeSet AudioFlinger::primaryOutputDevice_l() const
 {
-    PlaybackThread *thread = primaryPlaybackThread_l();
+    IAfPlaybackThread* const thread = primaryPlaybackThread_l();
 
     if (thread == NULL) {
         return {};
@@ -3908,12 +3918,12 @@
     return thread->outDeviceTypes();
 }
 
-AudioFlinger::PlaybackThread *AudioFlinger::fastPlaybackThread_l() const
+IAfPlaybackThread* AudioFlinger::fastPlaybackThread_l() const
 {
     size_t minFrameCount = 0;
-    PlaybackThread *minThread = NULL;
+    IAfPlaybackThread* minThread = nullptr;
     for (size_t i = 0; i < mPlaybackThreads.size(); i++) {
-        PlaybackThread *thread = mPlaybackThreads.valueAt(i).get();
+        IAfPlaybackThread* const thread = mPlaybackThreads.valueAt(i).get();
         if (!thread->isDuplicating()) {
             size_t frameCount = thread->frameCountHAL();
             if (frameCount != 0 && (minFrameCount == 0 || frameCount < minFrameCount ||
@@ -3927,9 +3937,9 @@
     return minThread;
 }
 
-AudioFlinger::ThreadBase *AudioFlinger::hapticPlaybackThread_l() const {
+IAfThreadBase* AudioFlinger::hapticPlaybackThread_l() const {
     for (size_t i  = 0; i < mPlaybackThreads.size(); ++i) {
-        PlaybackThread *thread = mPlaybackThreads.valueAt(i).get();
+        IAfPlaybackThread* const thread = mPlaybackThreads.valueAt(i).get();
         if (thread->hapticChannelMask() != AUDIO_CHANNEL_NONE) {
             return thread;
         }
@@ -3939,11 +3949,11 @@
 
 void AudioFlinger::updateSecondaryOutputsForTrack_l(
         IAfTrack* track,
-        PlaybackThread* thread,
+        IAfPlaybackThread* thread,
         const std::vector<audio_io_handle_t> &secondaryOutputs) const {
     TeePatches teePatches;
     for (audio_io_handle_t secondaryOutput : secondaryOutputs) {
-        PlaybackThread *secondaryThread = checkPlaybackThread_l(secondaryOutput);
+        IAfPlaybackThread* const secondaryThread = checkPlaybackThread_l(secondaryOutput);
         if (secondaryThread == nullptr) {
             ALOGE("no playback thread found for secondary output %d", thread->id());
             continue;
@@ -3969,10 +3979,10 @@
         // The frameCount should also not be smaller than the secondary thread min frame
         // count
         size_t minFrameCount = AudioSystem::calculateMinFrameCount(
-                    [&] { Mutex::Autolock _l(secondaryThread->mLock);
+                    [&] { Mutex::Autolock _l(secondaryThread->mutex());
                           return secondaryThread->latency_l(); }(),
-                    secondaryThread->mNormalFrameCount,
-                    secondaryThread->mSampleRate,
+                    secondaryThread->frameCount(), // normal frame count
+                    secondaryThread->sampleRate(),
                     track->sampleRate(),
                     track->getSpeed());
         frameCount = std::max(frameCount, minFrameCount);
@@ -4028,7 +4038,7 @@
         patchTrack->setPeerProxy(patchRecord, true /* holdReference */);
         patchRecord->setPeerProxy(patchTrack, false /* holdReference */);
     }
-    track->setTeePatchesToUpdate_l(&teePatches);  // TODO(b/288339104) void* to std::move()
+    track->setTeePatchesToUpdate_l(std::move(teePatches));
 }
 
 sp<audioflinger::SyncEvent> AudioFlinger::createSyncEvent(AudioSystem::sync_event_t type,
@@ -4221,7 +4231,7 @@
             lStatus = BAD_VALUE;
             goto Exit;
         }
-        PlaybackThread *thread = checkPlaybackThread_l(io);
+        IAfPlaybackThread* const thread = checkPlaybackThread_l(io);
         if (thread == nullptr) {
             ALOGE("%s: invalid output %d specified for AUDIO_SESSION_OUTPUT_STAGE", __func__, io);
             lStatus = BAD_VALUE;
@@ -4318,7 +4328,7 @@
             sp<Client> client = registerPid(currentPid);
             ALOGV("%s device type %#x address %s", __func__, device.mType, device.getAddress());
             handle = mDeviceEffectManager->createEffect_l(
-                    &descOut, device, client, effectClient, mPatchPanel.patches_l(),
+                    &descOut, device, client, effectClient, mPatchPanel->patches_l(),
                     &enabledOut, &lStatus, probe, request.notifyFramesProcessed);
             if (lStatus != NO_ERROR && lStatus != ALREADY_EXISTS) {
                 // remove local strong reference to Client with mClientLock held
@@ -4390,7 +4400,7 @@
                 }
                 const uint32_t sessionType =
                         mPlaybackThreads.valueAt(i)->hasAudioSession(sessionId);
-                if ((sessionType & ThreadBase::EFFECT_SESSION) != 0) {
+                if ((sessionType & IAfThreadBase::EFFECT_SESSION) != 0) {
                     ALOGE("%s: effect %s io %d denied because session %d effect exists on io %d",
                           __func__, descOut.name, (int) io, (int) sessionId, (int) checkIo);
                     android_errorWriteLog(0x534e4554, "123237974");
@@ -4399,7 +4409,7 @@
                 }
             }
         }
-        ThreadBase *thread = checkRecordThread_l(io);
+        IAfThreadBase* thread = checkRecordThread_l(io);
         if (thread == NULL) {
             thread = checkPlaybackThread_l(io);
             if (thread == NULL) {
@@ -4415,7 +4425,7 @@
             // session and used it instead of creating a new one.
             sp<IAfEffectChain> chain = getOrphanEffectChain_l(sessionId);
             if (chain != 0) {
-                Mutex::Autolock _l2(thread->mLock);
+                Mutex::Autolock _l2(thread->mutex());
                 thread->addEffectChain_l(chain);
             }
         }
@@ -4424,9 +4434,9 @@
 
         // create effect on selected output thread
         bool pinned = !audio_is_global_session(sessionId) && isSessionAcquired_l(sessionId);
-        ThreadBase *oriThread = nullptr;
+        IAfThreadBase* oriThread = nullptr;
         if (hapticPlaybackRequired && thread->hapticChannelMask() == AUDIO_CHANNEL_NONE) {
-            ThreadBase *hapticThread = hapticPlaybackThread_l();
+            IAfThreadBase* const hapticThread = hapticPlaybackThread_l();
             if (hapticThread == nullptr) {
                 ALOGE("%s haptic thread not found while it is required", __func__);
                 lStatus = INVALID_OPERATION;
@@ -4496,37 +4506,37 @@
         ALOGW("%s() same dst and src outputs %d", __func__, dstIo);
         return NO_ERROR;
     }
-    RecordThread *srcRecordThread = checkRecordThread_l(srcIo);
-    RecordThread *dstRecordThread = checkRecordThread_l(dstIo);
+    IAfRecordThread* const srcRecordThread = checkRecordThread_l(srcIo);
+    IAfRecordThread* const dstRecordThread = checkRecordThread_l(dstIo);
     if (srcRecordThread != nullptr || dstRecordThread != nullptr) {
         if (srcRecordThread != nullptr) {
-            srcRecordThread->mLock.lock();
+            srcRecordThread->mutex().lock();
         }
         if (dstRecordThread != nullptr) {
-            dstRecordThread->mLock.lock();
+            dstRecordThread->mutex().lock();
         }
         status_t ret = moveEffectChain_l(sessionId, srcRecordThread, dstRecordThread);
         if (srcRecordThread != nullptr) {
-            srcRecordThread->mLock.unlock();
+            srcRecordThread->mutex().unlock();
         }
         if (dstRecordThread != nullptr) {
-            dstRecordThread->mLock.unlock();
+            dstRecordThread->mutex().unlock();
         }
         return ret;
     }
-    PlaybackThread *srcThread = checkPlaybackThread_l(srcIo);
+    IAfPlaybackThread* const srcThread = checkPlaybackThread_l(srcIo);
     if (srcThread == nullptr) {
         ALOGW("%s() bad srcIo %d", __func__, srcIo);
         return BAD_VALUE;
     }
-    PlaybackThread *dstThread = checkPlaybackThread_l(dstIo);
+    IAfPlaybackThread* const dstThread = checkPlaybackThread_l(dstIo);
     if (dstThread == nullptr) {
         ALOGW("%s() bad dstIo %d", __func__, dstIo);
         return BAD_VALUE;
     }
 
-    Mutex::Autolock _dl(dstThread->mLock);
-    Mutex::Autolock _sl(srcThread->mLock);
+    Mutex::Autolock _dl(dstThread->mutex());
+    Mutex::Autolock _sl(srcThread->mutex());
     return moveEffectChain_l(sessionId, srcThread, dstThread);
 }
 
@@ -4537,11 +4547,11 @@
 {
     Mutex::Autolock _l(mLock);
 
-    sp<ThreadBase> thread = getEffectThread_l(sessionId, effectId);
+    sp<IAfThreadBase> thread = getEffectThread_l(sessionId, effectId);
     if (thread == nullptr) {
       return;
     }
-    Mutex::Autolock _sl(thread->mLock);
+    Mutex::Autolock _sl(thread->mutex());
     sp<IAfEffectModule> effect = thread->getEffect_l(sessionId, effectId);
     thread->setEffectSuspended_l(&effect->desc().type, suspended, sessionId);
 }
@@ -4549,8 +4559,7 @@
 
 // moveEffectChain_l must be called with both srcThread and dstThread mLocks held
 status_t AudioFlinger::moveEffectChain_l(audio_session_t sessionId,
-                                   AudioFlinger::PlaybackThread *srcThread,
-                                   AudioFlinger::PlaybackThread *dstThread)
+        IAfPlaybackThread* srcThread, IAfPlaybackThread* dstThread)
 NO_THREAD_SAFETY_ANALYSIS // requires srcThread and dstThread locks
 {
     ALOGV("moveEffectChain_l() session %d from thread %p to thread %p",
@@ -4663,13 +4672,12 @@
 // moveEffectChain_l must be called with both srcThread (if not null) and dstThread (if not null)
 // mLocks held
 status_t AudioFlinger::moveEffectChain_l(audio_session_t sessionId,
-                                         RecordThread *srcThread,
-                                         RecordThread *dstThread)
+        IAfRecordThread* srcThread, IAfRecordThread* dstThread)
 NO_THREAD_SAFETY_ANALYSIS // requires srcThread and dstThread locks
 {
     sp<IAfEffectChain> chain = nullptr;
     if (srcThread != 0) {
-        Vector< sp<IAfEffectChain> > effectChains = srcThread->getEffectChains_l();
+        const Vector<sp<IAfEffectChain>> effectChains = srcThread->getEffectChains_l();
         for (size_t i = 0; i < effectChains.size(); i ++) {
              if (effectChains[i]->sessionId() == sessionId) {
                  chain = effectChains[i];
@@ -4704,17 +4712,16 @@
 }
 
 status_t AudioFlinger::moveAuxEffectToIo(int EffectId,
-                                         const sp<PlaybackThread>& dstThread,
-                                         sp<PlaybackThread> *srcThread)
+        const sp<IAfPlaybackThread>& dstThread, sp<IAfPlaybackThread>* srcThread)
 {
     status_t status = NO_ERROR;
     Mutex::Autolock _l(mLock);
-    sp<PlaybackThread> thread =
-        static_cast<PlaybackThread *>(getEffectThread_l(AUDIO_SESSION_OUTPUT_MIX, EffectId).get());
+    const sp<IAfThreadBase> threadBase = getEffectThread_l(AUDIO_SESSION_OUTPUT_MIX, EffectId);
+    const sp<IAfPlaybackThread> thread = threadBase ? threadBase->asIAfPlaybackThread() : nullptr;
 
     if (EffectId != 0 && thread != 0 && dstThread != thread.get()) {
-        Mutex::Autolock _dl(dstThread->mLock);
-        Mutex::Autolock _sl(thread->mLock);
+        Mutex::Autolock _dl(dstThread->mutex());
+        Mutex::Autolock _sl(thread->mutex());
         sp<IAfEffectChain> srcChain = thread->getEffectChain_l(AUDIO_SESSION_OUTPUT_MIX);
         sp<IAfEffectChain> dstChain;
         if (srcChain == 0) {
@@ -4778,8 +4785,8 @@
     mGlobalEffectEnableTime = systemTime();
 
     for (size_t i = 0; i < mPlaybackThreads.size(); i++) {
-        sp<PlaybackThread> t = mPlaybackThreads.valueAt(i);
-        if (t->mType == ThreadBase::OFFLOAD) {
+        const sp<IAfPlaybackThread> t = mPlaybackThreads.valueAt(i);
+        if (t->type() == IAfThreadBase::OFFLOAD) {
             t->invalidateTracks(AUDIO_STREAM_MUSIC);
         }
     }
diff --git a/services/audioflinger/AudioFlinger.h b/services/audioflinger/AudioFlinger.h
index 0e7bd1b..e3910ea 100644
--- a/services/audioflinger/AudioFlinger.h
+++ b/services/audioflinger/AudioFlinger.h
@@ -98,10 +98,12 @@
 #include <timing/SynchronizedRecordState.h>
 
 #include <datapath/AudioHwDevice.h>
+#include <datapath/AudioStreamIn.h>
 #include <datapath/AudioStreamOut.h>
 #include <datapath/SpdifStreamOut.h>
 #include <datapath/ThreadMetrics.h>
 #include <datapath/TrackMetrics.h>
+#include <datapath/VolumeInterface.h>
 #include <fastpath/FastCapture.h>
 #include <fastpath/FastMixer.h>
 #include <media/nbaio/NBAIO.h>
@@ -122,9 +124,16 @@
 #include "ResamplerBufferProvider.h"
 
 // include AudioFlinger component interfaces
+#include "IAfPatchPanel.h"  // this should be listed before other IAf* interfaces.
 #include "IAfEffect.h"
+#include "IAfThread.h"
 #include "IAfTrack.h"
 
+// Classes that depend on IAf* interfaces but are not cross-dependent.
+#include "PatchCommandThread.h"
+#include "DeviceEffectManager.h"
+#include "MelReporter.h"
+
 namespace android {
 
 class AudioMixer;
@@ -143,14 +152,31 @@
 
 static const nsecs_t kDefaultStandbyTimeInNsecs = seconds(3);
 
-#define INCLUDING_FROM_AUDIOFLINGER_H
-
 using android::content::AttributionSourceState;
 
+struct stream_type_t {
+    float volume = 1.f;
+    bool mute = false;
+};
+
 class AudioFlinger : public AudioFlingerServerAdapter::Delegate
 {
     friend class sp<AudioFlinger>;
+    // TODO(b/291319167) Create interface and remove friends.
     friend class Client; // removeClient_l();
+    friend class DeviceEffectManager;
+    friend class DeviceEffectManagerCallback;
+    friend class MelReporter;
+    friend class PatchPanel;
+    // TODO(b/291012167) replace the Thread friends with an interface.
+    friend class DirectOutputThread;
+    friend class MixerThread;
+    friend class MmapPlaybackThread;
+    friend class MmapThread;
+    friend class PlaybackThread;
+    friend class RecordThread;
+    friend class ThreadBase;
+
 public:
     static void instantiate() ANDROID_API;
 
@@ -487,7 +513,7 @@
     // Internal dump utilities.
     static const int kDumpLockTimeoutNs = 1 * NANOS_PER_SECOND;
 public:
-    // TODO(b/288339104) extract to afutils
+    // TODO(b/291319167) extract to afutils
     static bool dumpTryLock(Mutex& mutex);
 private:
     void dumpPermissionDenial(int fd, const Vector<String16>& args);
@@ -496,11 +522,7 @@
 
     SimpleLog mThreadLog{16}; // 16 Thread history limit
 
-public:
-    // TODO(b/288339104)
-    class ThreadBase;
-private:
-    void dumpToThreadLog_l(const sp<ThreadBase> &thread);
+    void dumpToThreadLog_l(const sp<IAfThreadBase>& thread);
 
     // --- Notification Client ---
     class NotificationClient : public IBinder::DeathRecipient {
@@ -560,51 +582,6 @@
     // Requests media.log to start merging log buffers
     void requestLogMerge();
 
-    // TODO(b/288339104) replace these forward declaration classes with interfaces.
-public:
-    class RecordThread;
-    class PlaybackThread;
-    class MixerThread;
-    class DirectOutputThread;
-    class OffloadThread;
-    class DuplicatingThread;
-    class AsyncCallbackThread;
-    class BitPerfectThread;
-private:
-    class DeviceEffectManager;
-    // TODO(b/288339104) these should be separate files
-public:
-    class PatchPanel;
-    class DeviceEffectManagerCallback;
-private:
-    struct AudioStreamIn;
-    struct TeePatch;
-public:
-    using TeePatches = std::vector<TeePatch>;
-private:
-
-    struct  stream_type_t {
-        stream_type_t()
-            :   volume(1.0f),
-                mute(false)
-        {
-        }
-        float       volume;
-        bool        mute;
-    };
-
-    // --- PlaybackThread ---
-
-#include "Threads.h"
-
-#include "PatchPanel.h"
-
-#include "PatchCommandThread.h"
-
-#include "DeviceEffectManager.h"
-
-#include "MelReporter.h"
-
     // Find io handle by session id.
     // Preference is given to an io handle with a matching effect chain to session id.
     // If none found, AUDIO_IO_HANDLE_NONE is returned.
@@ -617,7 +594,7 @@
             const uint32_t sessionType = threads.valueAt(i)->hasAudioSession(sessionId);
             if (sessionType != 0) {
                 io = threads.keyAt(i);
-                if ((sessionType & AudioFlinger::ThreadBase::EFFECT_SESSION) != 0) {
+                if ((sessionType & IAfThreadBase::EFFECT_SESSION) != 0) {
                     break; // effect chain here.
                 }
             }
@@ -625,40 +602,16 @@
         return io;
     }
 
-    // Mmap stream control interface implementation. Each MmapThreadHandle controls one
-    // MmapPlaybackThread or MmapCaptureThread instance.
-    class MmapThreadHandle : public MmapStreamInterface {
-    public:
-        explicit            MmapThreadHandle(const sp<MmapThread>& thread);
-        virtual             ~MmapThreadHandle();
+    IAfThreadBase* checkThread_l(audio_io_handle_t ioHandle) const;
+    sp<IAfThreadBase> checkOutputThread_l(audio_io_handle_t ioHandle) const REQUIRES(mLock);
+    IAfPlaybackThread* checkPlaybackThread_l(audio_io_handle_t output) const;
+    IAfPlaybackThread* checkMixerThread_l(audio_io_handle_t output) const;
+    IAfRecordThread* checkRecordThread_l(audio_io_handle_t input) const;
+    IAfMmapThread* checkMmapThread_l(audio_io_handle_t io) const;
+              sp<VolumeInterface> getVolumeInterface_l(audio_io_handle_t output) const;
+              std::vector<sp<VolumeInterface>> getAllVolumeInterfaces_l() const;
 
-        // MmapStreamInterface virtuals
-        virtual status_t createMmapBuffer(int32_t minSizeFrames,
-                                          struct audio_mmap_buffer_info *info);
-        virtual status_t getMmapPosition(struct audio_mmap_position *position);
-        virtual status_t getExternalPosition(uint64_t *position, int64_t *timeNanos);
-        virtual status_t start(const AudioClient& client,
-                               const audio_attributes_t *attr,
-                               audio_port_handle_t *handle);
-        virtual status_t stop(audio_port_handle_t handle);
-        virtual status_t standby();
-                status_t reportData(const void* buffer, size_t frameCount) override;
-
-    private:
-        const sp<MmapThread> mThread;
-    };
-
-              ThreadBase *checkThread_l(audio_io_handle_t ioHandle) const;
-              sp<AudioFlinger::ThreadBase> checkOutputThread_l(audio_io_handle_t ioHandle) const
-                      REQUIRES(mLock);
-              PlaybackThread *checkPlaybackThread_l(audio_io_handle_t output) const;
-              MixerThread *checkMixerThread_l(audio_io_handle_t output) const;
-              RecordThread *checkRecordThread_l(audio_io_handle_t input) const;
-              MmapThread *checkMmapThread_l(audio_io_handle_t io) const;
-              VolumeInterface *getVolumeInterface_l(audio_io_handle_t output) const;
-              Vector <VolumeInterface *> getAllVolumeInterfaces_l() const;
-
-              sp<ThreadBase> openInput_l(audio_module_handle_t module,
+    sp<IAfThreadBase> openInput_l(audio_module_handle_t module,
                                            audio_io_handle_t *input,
                                            audio_config_t *config,
                                            audio_devices_t device,
@@ -667,7 +620,7 @@
                                            audio_input_flags_t flags,
                                            audio_devices_t outputDevice,
                                            const String8& outputDeviceAddress);
-              sp<ThreadBase> openOutput_l(audio_module_handle_t module,
+    sp<IAfThreadBase> openOutput_l(audio_module_handle_t module,
                                           audio_io_handle_t *output,
                                           audio_config_t *halConfig,
                                           audio_config_base_t *mixerConfig,
@@ -675,8 +628,8 @@
                                           const String8& address,
                                           audio_output_flags_t flags);
 
-              void closeOutputFinish(const sp<PlaybackThread>& thread);
-              void closeInputFinish(const sp<RecordThread>& thread);
+    void closeOutputFinish(const sp<IAfPlaybackThread>& thread);
+    void closeInputFinish(const sp<IAfRecordThread>& thread);
 
               // no range check, AudioFlinger::mLock held
               bool streamMute_l(audio_stream_type_t stream) const
@@ -701,40 +654,37 @@
               audio_unique_id_t nextUniqueId(audio_unique_id_use_t use);
 
               status_t moveEffectChain_l(audio_session_t sessionId,
-                                     PlaybackThread *srcThread,
-                                     PlaybackThread *dstThread);
+            IAfPlaybackThread* srcThread, IAfPlaybackThread* dstThread);
               status_t moveEffectChain_l(audio_session_t sessionId,
-                                         RecordThread *srcThread,
-                                         RecordThread *dstThread);
+            IAfRecordThread* srcThread, IAfRecordThread* dstThread);
 
 public:
-    // TODO(b/288339104) cluster together
+    // TODO(b/291319167) cluster together
               status_t moveAuxEffectToIo(int EffectId,
-                                         const sp<PlaybackThread>& dstThread,
-                                         sp<PlaybackThread> *srcThread);
+            const sp<IAfPlaybackThread>& dstThread, sp<IAfPlaybackThread>* srcThread);
 private:
 
               // return thread associated with primary hardware device, or NULL
-              PlaybackThread *primaryPlaybackThread_l() const;
+              IAfPlaybackThread* primaryPlaybackThread_l() const;
               DeviceTypeSet primaryOutputDevice_l() const;
 
               // return the playback thread with smallest HAL buffer size, and prefer fast
-              PlaybackThread *fastPlaybackThread_l() const;
+              IAfPlaybackThread* fastPlaybackThread_l() const;
 
-              sp<ThreadBase> getEffectThread_l(audio_session_t sessionId, int effectId);
+              sp<IAfThreadBase> getEffectThread_l(audio_session_t sessionId, int effectId);
 
-              ThreadBase *hapticPlaybackThread_l() const;
+              IAfThreadBase* hapticPlaybackThread_l() const;
 
               void updateSecondaryOutputsForTrack_l(
                       IAfTrack* track,
-                      PlaybackThread* thread,
+                      IAfPlaybackThread* thread,
                       const std::vector<audio_io_handle_t>& secondaryOutputs) const;
 
 
                 void        removeClient_l(pid_t pid);
                 void        removeNotificationClient(pid_t pid);
 public:
-    // TODO(b/288339104) cluster together
+    // TODO(b/291319167) cluster together
                 bool isNonOffloadableGlobalEffectEnabled_l();
 private:
                 void onNonOffloadableGlobalEffectEnable();
@@ -756,7 +706,7 @@
                 // and removed from mOrphanEffectChains if it does not contain any effect.
                 // Return true if the effect was found in mOrphanEffectChains, false otherwise.
 public:
-// TODO(b/288339104) suggest better grouping
+// TODO(b/291319167) suggest better grouping
                 bool updateOrphanEffectChains(const sp<IAfEffectModule>& effect);
 private:
                 std::vector< sp<IAfEffectModule> > purgeStaleEffects_l();
@@ -768,35 +718,7 @@
                 void updateOutDevicesForRecordThreads_l(const DeviceDescriptorBaseVector& devices);
                 void forwardParametersToDownstreamPatches_l(
                         audio_io_handle_t upStream, const String8& keyValuePairs,
-                        const std::function<bool(const sp<PlaybackThread>&)>& useThread = nullptr);
-
-    // AudioStreamIn is immutable, so their fields are const.
-    // For emphasis, we could also make all pointers to them be "const *",
-    // but that would clutter the code unnecessarily.
-
-    struct AudioStreamIn : public Source {
-        AudioHwDevice* const audioHwDev;
-        sp<StreamInHalInterface> stream;
-        audio_input_flags_t flags;
-
-        sp<DeviceHalInterface> hwDev() const { return audioHwDev->hwDevice(); }
-
-        AudioStreamIn(AudioHwDevice *dev, const sp<StreamInHalInterface>& in,
-                audio_input_flags_t flags) :
-            audioHwDev(dev), stream(in), flags(flags) {}
-        status_t read(void *buffer, size_t bytes, size_t *read) override {
-            return stream->read(buffer, bytes, read);
-        }
-        status_t getCapturePosition(int64_t *frames, int64_t *time) override {
-            return stream->getCapturePosition(frames, time);
-        }
-        status_t standby() override { return stream->standby(); }
-    };
-
-    struct TeePatch {
-        sp<IAfPatchRecord> patchRecord;
-        sp<IAfPatchTrack> patchTrack;
-    };
+            const std::function<bool(const sp<IAfPlaybackThread>&)>& useThread = nullptr);
 
     // for mAudioSessionRefs only
     struct AudioSessionRef {
@@ -809,13 +731,13 @@
     };
 
 public:
-    // TODO(b/288339104) access by getter,
+    // TODO(b/291319167) access by getter,
     mutable     Mutex                               mLock;
                 // protects mClients and mNotificationClients.
                 // must be locked after mLock and ThreadBase::mLock if both must be locked
                 // avoids acquiring AudioFlinger::mLock from inside thread loop.
 
-    // TODO(b/288339104) access by getter,
+    // TODO(b/291319167) access by getter,
     mutable     Mutex                               mClientLock;
 private:
                 // protected by mClientLock
@@ -864,7 +786,7 @@
     mutable     hardware_call_state                 mHardwareStatus;    // for dump only
 
 
-                DefaultKeyedVector< audio_io_handle_t, sp<PlaybackThread> >  mPlaybackThreads;
+    DefaultKeyedVector<audio_io_handle_t, sp<IAfPlaybackThread>> mPlaybackThreads;
                 stream_type_t                       mStreamTypes[AUDIO_STREAM_CNT];
 
                 // member variables below are protected by mLock
@@ -873,7 +795,7 @@
                 float                               mMasterBalance = 0.f;
                 // end of variables protected by mLock
 
-                DefaultKeyedVector< audio_io_handle_t, sp<RecordThread> >    mRecordThreads;
+    DefaultKeyedVector<audio_io_handle_t, sp<IAfRecordThread>> mRecordThreads;
 
                 // protected by mClientLock
                 DefaultKeyedVector< pid_t, sp<NotificationClient> >    mNotificationClients;
@@ -904,17 +826,17 @@
                 // list of MMAP stream control threads. Those threads allow for wake lock, routing
                 // and volume control for activity on the associated MMAP stream at the HAL.
                 // Audio data transfer is directly handled by the client creating the MMAP stream
-                DefaultKeyedVector< audio_io_handle_t, sp<MmapThread> >  mMmapThreads;
+    DefaultKeyedVector<audio_io_handle_t, sp<IAfMmapThread>> mMmapThreads;
 
 private:
     sp<Client>  registerPid(pid_t pid);    // always returns non-0
 
     // for use from destructor
     status_t    closeOutput_nonvirtual(audio_io_handle_t output);
-    void        closeThreadInternal_l(const sp<PlaybackThread>& thread);
+    void closeThreadInternal_l(const sp<IAfPlaybackThread>& thread);
     status_t    closeInput_nonvirtual(audio_io_handle_t input);
-    void        closeThreadInternal_l(const sp<RecordThread>& thread);
-    void        setAudioHwSyncForSession_l(PlaybackThread *thread, audio_session_t sessionId);
+    void closeThreadInternal_l(const sp<IAfRecordThread>& thread);
+    void setAudioHwSyncForSession_l(IAfPlaybackThread* thread, audio_session_t sessionId);
 
     status_t    checkStreamType(audio_stream_type_t stream) const;
 
@@ -941,9 +863,10 @@
     nsecs_t mGlobalEffectEnableTime;  // when a global effect was last enabled
 
     // protected by mLock
-    PatchPanel mPatchPanel;
+    const sp<IAfPatchPanel> mPatchPanel = IAfPatchPanel::create(this);
+
 public:
-    // TODO(b/288339104) access by getter.
+    // TODO(b/291319167) access by getter.
     sp<EffectsFactoryHalInterface> mEffectsFactoryHal;
 private:
 
@@ -979,8 +902,6 @@
     std::atomic_bool mBluetoothLatencyModesEnabled;
 };
 
-#undef INCLUDING_FROM_AUDIOFLINGER_H
-
 std::string formatToString(audio_format_t format);
 std::string inputFlagsToString(audio_input_flags_t flags);
 std::string outputFlagsToString(audio_output_flags_t flags);
diff --git a/services/audioflinger/Client.h b/services/audioflinger/Client.h
index cb507fe..142d384 100644
--- a/services/audioflinger/Client.h
+++ b/services/audioflinger/Client.h
@@ -16,7 +16,7 @@
 
 #pragma once
 
-// TODO(b/288339104) Move to nested namespace
+// TODO(b/291318727) Move to nested namespace
 namespace android {
 
 class AudioFlinger;
diff --git a/services/audioflinger/DeviceEffectManager.cpp b/services/audioflinger/DeviceEffectManager.cpp
index 8e78e4a..0f645cd 100644
--- a/services/audioflinger/DeviceEffectManager.cpp
+++ b/services/audioflinger/DeviceEffectManager.cpp
@@ -16,7 +16,7 @@
 */
 
 
-#define LOG_TAG "AudioFlinger::DeviceEffectManager"
+#define LOG_TAG "DeviceEffectManager"
 //#define LOG_NDEBUG 0
 
 #include <utils/Log.h>
@@ -34,22 +34,40 @@
 using detail::AudioHalVersionInfo;
 using media::IEffectClient;
 
-void AudioFlinger::DeviceEffectManager::onCreateAudioPatch(audio_patch_handle_t handle,
-        const PatchPanel::Patch& patch) {
+DeviceEffectManager::DeviceEffectManager(AudioFlinger& audioFlinger)
+    : mAudioFlinger(audioFlinger),
+      mMyCallback(new DeviceEffectManagerCallback(*this)) {}
+
+void DeviceEffectManager::onFirstRef() {
+    mAudioFlinger.mPatchCommandThread->addListener(this);
+}
+
+status_t DeviceEffectManager::addEffectToHal(const struct audio_port_config* device,
+        const sp<EffectHalInterface>& effect) {
+    return mAudioFlinger.addEffectToHal(device, effect);
+};
+
+status_t DeviceEffectManager::removeEffectFromHal(const struct audio_port_config* device,
+        const sp<EffectHalInterface>& effect) {
+    return mAudioFlinger.removeEffectFromHal(device, effect);
+};
+
+void DeviceEffectManager::onCreateAudioPatch(audio_patch_handle_t handle,
+        const IAfPatchPanel::Patch& patch) {
     ALOGV("%s handle %d mHalHandle %d device sink %08x",
             __func__, handle, patch.mHalHandle,
             patch.mAudioPatch.num_sinks > 0 ? patch.mAudioPatch.sinks[0].ext.device.type : 0);
     Mutex::Autolock _l(mLock);
     for (auto& effectProxies : mDeviceEffects) {
         for (auto& effect : effectProxies.second) {
-            status_t status = effect->onCreatePatch(handle, &patch); // TODO(b/288339104) void*
+            const status_t status = effect->onCreatePatch(handle, patch);
             ALOGV("%s Effect onCreatePatch status %d", __func__, status);
             ALOGW_IF(status == BAD_VALUE, "%s onCreatePatch error %d", __func__, status);
         }
     }
 }
 
-void AudioFlinger::DeviceEffectManager::onReleaseAudioPatch(audio_patch_handle_t handle) {
+void DeviceEffectManager::onReleaseAudioPatch(audio_patch_handle_t handle) {
     ALOGV("%s", __func__);
     Mutex::Autolock _l(mLock);
     for (auto& effectProxies : mDeviceEffects) {
@@ -59,16 +77,15 @@
     }
 }
 
-void AudioFlinger::DeviceEffectManager::onUpdateAudioPatch(audio_patch_handle_t oldHandle,
-        audio_patch_handle_t newHandle, const PatchPanel::Patch& patch) {
+void DeviceEffectManager::onUpdateAudioPatch(audio_patch_handle_t oldHandle,
+        audio_patch_handle_t newHandle, const IAfPatchPanel::Patch& patch) {
     ALOGV("%s oldhandle %d newHandle %d mHalHandle %d device sink %08x",
             __func__, oldHandle, newHandle, patch.mHalHandle,
             patch.mAudioPatch.num_sinks > 0 ? patch.mAudioPatch.sinks[0].ext.device.type : 0);
     Mutex::Autolock _l(mLock);
     for (auto& effectProxies : mDeviceEffects) {
         for (auto& effect : effectProxies.second) {
-            // TODO(b/288339104) void*
-            status_t status = effect->onUpdatePatch(oldHandle, newHandle, &patch);
+            const status_t status = effect->onUpdatePatch(oldHandle, newHandle, patch);
             ALOGV("%s Effect onUpdatePatch status %d", __func__, status);
             ALOGW_IF(status != NO_ERROR, "%s onUpdatePatch error %d", __func__, status);
         }
@@ -76,12 +93,12 @@
 }
 
 // DeviceEffectManager::createEffect_l() must be called with AudioFlinger::mLock held
-sp<IAfEffectHandle> AudioFlinger::DeviceEffectManager::createEffect_l(
+sp<IAfEffectHandle> DeviceEffectManager::createEffect_l(
         effect_descriptor_t *descriptor,
         const AudioDeviceTypeAddr& device,
         const sp<Client>& client,
         const sp<IEffectClient>& effectClient,
-        const std::map<audio_patch_handle_t, PatchPanel::Patch>& patches,
+        const std::map<audio_patch_handle_t, IAfPatchPanel::Patch>& patches,
         int *enabled,
         status_t *status,
         bool probe,
@@ -123,7 +140,7 @@
         if (lStatus == NO_ERROR) {
             lStatus = effect->addHandle(handle.get());
             if (lStatus == NO_ERROR) {
-                lStatus = effect->init(&patches); // TODO(b/288339104) void*
+                lStatus = effect->init(patches);
                 if (lStatus == NAME_NOT_FOUND) {
                     lStatus = NO_ERROR;
                 }
@@ -141,7 +158,7 @@
     return handle;
 }
 
-status_t AudioFlinger::DeviceEffectManager::checkEffectCompatibility(
+status_t DeviceEffectManager::checkEffectCompatibility(
         const effect_descriptor_t *desc) {
     const sp<EffectsFactoryHalInterface> effectsFactory =
             audioflinger::EffectConfiguration::getEffectsFactoryHal();
@@ -167,7 +184,7 @@
     return NO_ERROR;
 }
 
-status_t AudioFlinger::DeviceEffectManager::createEffectHal(
+status_t DeviceEffectManager::createEffectHal(
         const effect_uuid_t *pEffectUuid, int32_t sessionId, int32_t deviceId,
         sp<EffectHalInterface> *effect) {
     status_t status = NO_INIT;
@@ -180,10 +197,10 @@
     return status;
 }
 
-void AudioFlinger::DeviceEffectManager::dump(int fd)
+void DeviceEffectManager::dump(int fd)
 NO_THREAD_SAFETY_ANALYSIS  // conditional try lock
 {
-    const bool locked = dumpTryLock(mLock);
+    const bool locked = AudioFlinger::dumpTryLock(mLock);
     if (!locked) {
         String8 result("DeviceEffectManager may be deadlocked\n");
         write(fd, result.string(), result.size());
@@ -206,7 +223,7 @@
     }
 }
 
-size_t AudioFlinger::DeviceEffectManager::removeEffect(const sp<IAfDeviceEffectProxy>& effect)
+size_t DeviceEffectManager::removeEffect(const sp<IAfDeviceEffectProxy>& effect)
 {
     Mutex::Autolock _l(mLock);
     const auto& iter = mDeviceEffects.find(effect->device());
@@ -226,7 +243,7 @@
     return mDeviceEffects.size();
 }
 
-bool AudioFlinger::DeviceEffectManagerCallback::disconnectEffectHandle(
+bool DeviceEffectManagerCallback::disconnectEffectHandle(
         IAfEffectHandle *handle, bool unpinIfLast) {
     sp<IAfEffectBase> effectBase = handle->effect().promote();
     if (effectBase == nullptr) {
@@ -248,4 +265,12 @@
     return true;
 }
 
+bool DeviceEffectManagerCallback::isAudioPolicyReady() const {
+    return mManager.audioFlinger().isAudioPolicyReady();
+}
+
+int DeviceEffectManagerCallback::newEffectId() const {
+    return mManager.audioFlinger().nextUniqueId(AUDIO_UNIQUE_ID_USE_EFFECT);
+}
+
 } // namespace android
diff --git a/services/audioflinger/DeviceEffectManager.h b/services/audioflinger/DeviceEffectManager.h
index bb031d6..54b88d0 100644
--- a/services/audioflinger/DeviceEffectManager.h
+++ b/services/audioflinger/DeviceEffectManager.h
@@ -15,26 +15,24 @@
 ** limitations under the License.
 */
 
-#ifndef INCLUDING_FROM_AUDIOFLINGER_H
-    #error This header file should only be included from AudioFlinger.h
-#endif
+#pragma once
+
+namespace android {
+
+class DeviceEffectManagerCallback;
 
 // DeviceEffectManager is concealed within AudioFlinger, their lifetimes are the same.
 class DeviceEffectManager : public PatchCommandThread::PatchCommandListener {
 public:
-    explicit DeviceEffectManager(AudioFlinger& audioFlinger)
-        : mAudioFlinger(audioFlinger),
-          mMyCallback(new DeviceEffectManagerCallback(*this)) {}
+    explicit DeviceEffectManager(AudioFlinger& audioFlinger);
 
-    void onFirstRef() override {
-        mAudioFlinger.mPatchCommandThread->addListener(this);
-    }
+    void onFirstRef() override;
 
     sp<IAfEffectHandle> createEffect_l(effect_descriptor_t *descriptor,
                 const AudioDeviceTypeAddr& device,
                 const sp<Client>& client,
                 const sp<media::IEffectClient>& effectClient,
-                const std::map<audio_patch_handle_t, PatchPanel::Patch>& patches,
+                const std::map<audio_patch_handle_t, IAfPatchPanel::Patch>& patches,
                 int *enabled,
                 status_t *status,
                 bool probe,
@@ -45,13 +43,9 @@
            int32_t sessionId, int32_t deviceId,
            sp<EffectHalInterface> *effect);
     status_t addEffectToHal(const struct audio_port_config *device,
-            const sp<EffectHalInterface>& effect) {
-        return mAudioFlinger.addEffectToHal(device, effect);
-    };
+            const sp<EffectHalInterface>& effect);
     status_t removeEffectFromHal(const struct audio_port_config *device,
-            const sp<EffectHalInterface>& effect) {
-        return mAudioFlinger.removeEffectFromHal(device, effect);
-    };
+            const sp<EffectHalInterface>& effect);
 
     AudioFlinger& audioFlinger() const { return mAudioFlinger; }
 
@@ -60,11 +54,11 @@
     // PatchCommandThread::PatchCommandListener implementation
 
     void onCreateAudioPatch(audio_patch_handle_t handle,
-                            const PatchPanel::Patch& patch) override;
-    void onReleaseAudioPatch(audio_patch_handle_t handle) override;
+            const IAfPatchPanel::Patch& patch) final;
+    void onReleaseAudioPatch(audio_patch_handle_t handle) final;
     void onUpdateAudioPatch(audio_patch_handle_t oldHandle,
                             audio_patch_handle_t newHandle,
-                            const PatchPanel::Patch& patch) override;
+                            const IAfPatchPanel::Patch& patch) final;
 
 private:
     status_t checkEffectCompatibility(const effect_descriptor_t *desc);
@@ -75,7 +69,6 @@
     std::map<AudioDeviceTypeAddr, std::vector<sp<IAfDeviceEffectProxy>>> mDeviceEffects;
 };
 
-public: // TODO(b/288339104) extract inner class.
 class DeviceEffectManagerCallback : public EffectCallbackInterface {
 public:
     explicit DeviceEffectManagerCallback(DeviceEffectManager& manager)
@@ -132,11 +125,9 @@
 
     wp<IAfEffectChain> chain() const override { return nullptr; }
 
-    bool isAudioPolicyReady() const override {
-        return mManager.audioFlinger().isAudioPolicyReady();
-    }
+    bool isAudioPolicyReady() const final;
 
-    int newEffectId() { return mManager.audioFlinger().nextUniqueId(AUDIO_UNIQUE_ID_USE_EFFECT); }
+    int newEffectId() const;
 
     status_t addEffectToHal(const struct audio_port_config *device,
             const sp<EffectHalInterface>& effect) {
@@ -149,4 +140,5 @@
 private:
     DeviceEffectManager& mManager;
 };
-private:
+
+}  // namespace android
diff --git a/services/audioflinger/Effects.cpp b/services/audioflinger/Effects.cpp
index 2a33991..5780d5d 100644
--- a/services/audioflinger/Effects.cpp
+++ b/services/audioflinger/Effects.cpp
@@ -2118,21 +2118,20 @@
 
 /* static */
 sp<IAfEffectChain> IAfEffectChain::create(
-        const wp<Thread /*ThreadBase*/>& wThread,  // TODO(b/288339104) update type
+        const wp<IAfThreadBase>& wThread,
         audio_session_t sessionId)
 {
-    // TODO(b/288339104) no weak pointer cast.
-    return sp<EffectChain>::make(sp<AudioFlinger::ThreadBase>::cast(wThread.promote()), sessionId);
+    return sp<EffectChain>::make(wThread, sessionId);
 }
 
-EffectChain::EffectChain(const wp<AudioFlinger::ThreadBase>& thread,
+EffectChain::EffectChain(const wp<IAfThreadBase>& thread,
                                        audio_session_t sessionId)
     : mSessionId(sessionId), mActiveTrackCnt(0), mTrackCnt(0), mTailBufferCount(0),
       mVolumeCtrlIdx(-1), mLeftVolume(UINT_MAX), mRightVolume(UINT_MAX),
       mNewLeftVolume(UINT_MAX), mNewRightVolume(UINT_MAX),
       mEffectCallback(new EffectCallback(wp<EffectChain>(this), thread))
 {
-    sp<AudioFlinger::ThreadBase> p = thread.promote();
+    const sp<IAfThreadBase> p = thread.promote();
     if (p == nullptr) {
         return;
     }
@@ -2145,7 +2144,7 @@
 {
 }
 
-// getEffectFromDesc_l() must be called with AudioFlinger::ThreadBase::mLock held
+// getEffectFromDesc_l() must be called with IAfThreadBase::mutex() held
 sp<IAfEffectModule> EffectChain::getEffectFromDesc_l(
         effect_descriptor_t *descriptor) const
 {
@@ -2159,7 +2158,7 @@
     return 0;
 }
 
-// getEffectFromId_l() must be called with AudioFlinger::ThreadBase::mLock held
+// getEffectFromId_l() must be called with IAfThreadBase::mutex() held
 sp<IAfEffectModule> EffectChain::getEffectFromId_l(int id) const
 {
     size_t size = mEffects.size();
@@ -2173,7 +2172,7 @@
     return 0;
 }
 
-// getEffectFromType_l() must be called with AudioFlinger::ThreadBase::mLock held
+// getEffectFromType_l() must be called with IAfThreadBase::mutex() held
 sp<IAfEffectModule> EffectChain::getEffectFromType_l(
         const effect_uuid_t *type) const
 {
@@ -2268,7 +2267,7 @@
     }
 }
 
-// createEffect_l() must be called with AudioFlinger::ThreadBase::mLock held
+// createEffect_l() must be called with IAfThreadBase::mutex() held
 status_t EffectChain::createEffect_l(sp<IAfEffectModule>& effect,
                                                    effect_descriptor_t *desc,
                                                    int id,
@@ -2287,13 +2286,13 @@
     return lStatus;
 }
 
-// addEffect_l() must be called with AudioFlinger::ThreadBase::mLock held
+// addEffect_l() must be called with IAfThreadBase::mutex() held
 status_t EffectChain::addEffect_l(const sp<IAfEffectModule>& effect)
 {
     Mutex::Autolock _l(mLock);
     return addEffect_ll(effect);
 }
-// addEffect_l() must be called with AudioFlinger::ThreadBase::mLock and EffectChain::mLock held
+// addEffect_l() must be called with IAfThreadBase::mLock and EffectChain::mutex() held
 status_t EffectChain::addEffect_ll(const sp<IAfEffectModule>& effect)
 {
     effect->setCallback(mEffectCallback);
@@ -2447,7 +2446,7 @@
     return idx_insert;
 }
 
-// removeEffect_l() must be called with AudioFlinger::ThreadBase::mLock held
+// removeEffect_l() must be called with IAfThreadBase::mutex() held
 size_t EffectChain::removeEffect_l(const sp<IAfEffectModule>& effect,
                                                  bool release)
 {
@@ -2495,7 +2494,7 @@
     return mEffects.size();
 }
 
-// setDevices_l() must be called with AudioFlinger::ThreadBase::mLock held
+// setDevices_l() must be called with IAfThreadBase::mutex() held
 void EffectChain::setDevices_l(const AudioDeviceTypeAddrVector &devices)
 {
     size_t size = mEffects.size();
@@ -2504,7 +2503,7 @@
     }
 }
 
-// setInputDevice_l() must be called with AudioFlinger::ThreadBase::mLock held
+// setInputDevice_l() must be called with IAfThreadBase::mutex() held
 void EffectChain::setInputDevice_l(const AudioDeviceTypeAddr &device)
 {
     size_t size = mEffects.size();
@@ -2513,7 +2512,7 @@
     }
 }
 
-// setMode_l() must be called with AudioFlinger::ThreadBase::mLock held
+// setMode_l() must be called with IAfThreadBase::mutex() held
 void EffectChain::setMode_l(audio_mode_t mode)
 {
     size_t size = mEffects.size();
@@ -2522,7 +2521,7 @@
     }
 }
 
-// setAudioSource_l() must be called with AudioFlinger::ThreadBase::mLock held
+// setAudioSource_l() must be called with IAfThreadBase::mutex() held
 void EffectChain::setAudioSource_l(audio_source_t source)
 {
     size_t size = mEffects.size();
@@ -2538,7 +2537,7 @@
     return false;
 }
 
-// setVolume_l() must be called with AudioFlinger::ThreadBase::mLock or EffectChain::mLock held
+// setVolume_l() must be called with IAfThreadBase::mLock or EffectChain::mLock held
 bool EffectChain::setVolume_l(uint32_t *left, uint32_t *right, bool force)
 {
     uint32_t newLeft = *left;
@@ -2605,7 +2604,7 @@
     return hasControl;
 }
 
-// resetVolume_l() must be called with AudioFlinger::ThreadBase::mLock or EffectChain::mLock held
+// resetVolume_l() must be called with IAfThreadBase::mutex() or EffectChain::mLock held
 void EffectChain::resetVolume_l()
 {
     if ((mLeftVolume != UINT_MAX) && (mRightVolume != UINT_MAX)) {
@@ -2616,7 +2615,7 @@
 }
 
 // containsHapticGeneratingEffect_l must be called with
-// AudioFlinger::ThreadBase::mLock or EffectChain::mLock held
+// IAfThreadBase::mutex() or EffectChain::mLock held
 bool EffectChain::containsHapticGeneratingEffect_l()
 {
     for (size_t i = 0; i < mEffects.size(); ++i) {
@@ -2685,7 +2684,7 @@
     }
 }
 
-// must be called with AudioFlinger::ThreadBase::mLock held
+// must be called with IAfThreadBase::mutex() held
 void EffectChain::setEffectSuspended_l(
         const effect_uuid_t *type, bool suspend)
 {
@@ -2741,7 +2740,7 @@
     }
 }
 
-// must be called with AudioFlinger::ThreadBase::mLock held
+// must be called with IAfThreadBase::mutex() held
 void EffectChain::setEffectSuspendedAll_l(bool suspend)
 {
     sp<SuspendedEffectDesc> desc;
@@ -2897,7 +2896,7 @@
     return false;
 }
 
-void EffectChain::setThread(const sp<AudioFlinger::ThreadBase>& thread)
+void EffectChain::setThread(const sp<IAfThreadBase>& thread)
 {
     Mutex::Autolock _l(mLock);
     mEffectCallback->setThread(thread);
@@ -2964,7 +2963,7 @@
 }
 
 // isCompatibleWithThread_l() must be called with thread->mLock held
-bool EffectChain::isCompatibleWithThread_l(const sp<AudioFlinger::ThreadBase>& thread) const
+bool EffectChain::isCompatibleWithThread_l(const sp<IAfThreadBase>& thread) const
 {
     Mutex::Autolock _l(mLock);
     for (size_t i = 0; i < mEffects.size(); i++) {
@@ -3002,7 +3001,7 @@
 status_t EffectChain::EffectCallback::addEffectToHal(
         const sp<EffectHalInterface>& effect) {
     status_t result = NO_INIT;
-    sp<AudioFlinger::ThreadBase> t = thread().promote();
+    const sp<IAfThreadBase> t = thread().promote();
     if (t == nullptr) {
         return result;
     }
@@ -3018,7 +3017,7 @@
 status_t EffectChain::EffectCallback::removeEffectFromHal(
         const sp<EffectHalInterface>& effect) {
     status_t result = NO_INIT;
-    sp<AudioFlinger::ThreadBase> t = thread().promote();
+    const sp<IAfThreadBase> t = thread().promote();
     if (t == nullptr) {
         return result;
     }
@@ -3032,7 +3031,7 @@
 }
 
 audio_io_handle_t EffectChain::EffectCallback::io() const {
-    sp<AudioFlinger::ThreadBase> t = thread().promote();
+    const sp<IAfThreadBase> t = thread().promote();
     if (t == nullptr) {
         return AUDIO_IO_HANDLE_NONE;
     }
@@ -3040,7 +3039,7 @@
 }
 
 bool EffectChain::EffectCallback::isOutput() const {
-    sp<AudioFlinger::ThreadBase> t = thread().promote();
+    const sp<IAfThreadBase> t = thread().promote();
     if (t == nullptr) {
         return true;
     }
@@ -3048,19 +3047,19 @@
 }
 
 bool EffectChain::EffectCallback::isOffload() const {
-    return mThreadType == AudioFlinger::ThreadBase::OFFLOAD;
+    return mThreadType == IAfThreadBase::OFFLOAD;
 }
 
 bool EffectChain::EffectCallback::isOffloadOrDirect() const {
-    return mThreadType == AudioFlinger::ThreadBase::OFFLOAD
-            || mThreadType == AudioFlinger::ThreadBase::DIRECT;
+    return mThreadType == IAfThreadBase::OFFLOAD
+            || mThreadType == IAfThreadBase::DIRECT;
 }
 
 bool EffectChain::EffectCallback::isOffloadOrMmap() const {
     switch (mThreadType) {
-    case AudioFlinger::ThreadBase::OFFLOAD:
-    case AudioFlinger::ThreadBase::MMAP_PLAYBACK:
-    case AudioFlinger::ThreadBase::MMAP_CAPTURE:
+    case IAfThreadBase::OFFLOAD:
+    case IAfThreadBase::MMAP_PLAYBACK:
+    case IAfThreadBase::MMAP_CAPTURE:
         return true;
     default:
         return false;
@@ -3068,11 +3067,11 @@
 }
 
 bool EffectChain::EffectCallback::isSpatializer() const {
-    return mThreadType == AudioFlinger::ThreadBase::SPATIALIZER;
+    return mThreadType == IAfThreadBase::SPATIALIZER;
 }
 
 uint32_t EffectChain::EffectCallback::sampleRate() const {
-    sp<AudioFlinger::ThreadBase> t = thread().promote();
+    const sp<IAfThreadBase> t = thread().promote();
     if (t == nullptr) {
         return 0;
     }
@@ -3080,7 +3079,7 @@
 }
 
 audio_channel_mask_t EffectChain::EffectCallback::inChannelMask(int id) const {
-    sp<AudioFlinger::ThreadBase> t = thread().promote();
+    const sp<IAfThreadBase> t = thread().promote();
     if (t == nullptr) {
         return AUDIO_CHANNEL_NONE;
     }
@@ -3089,7 +3088,7 @@
         return AUDIO_CHANNEL_NONE;
     }
 
-    if (mThreadType == AudioFlinger::ThreadBase::SPATIALIZER) {
+    if (mThreadType == IAfThreadBase::SPATIALIZER) {
         if (c->sessionId() == AUDIO_SESSION_OUTPUT_STAGE) {
             if (c->isFirstEffect(id)) {
                 return t->mixerChannelMask();
@@ -3098,7 +3097,7 @@
             }
         } else if (!audio_is_global_session(c->sessionId())) {
             if ((t->hasAudioSession_l(c->sessionId())
-                    & AudioFlinger::ThreadBase::SPATIALIZED_SESSION) != 0) {
+                    & IAfThreadBase::SPATIALIZED_SESSION) != 0) {
                 return t->mixerChannelMask();
             } else {
                 return t->channelMask();
@@ -3116,7 +3115,7 @@
 }
 
 audio_channel_mask_t EffectChain::EffectCallback::outChannelMask() const {
-    sp<AudioFlinger::ThreadBase> t = thread().promote();
+    const sp<IAfThreadBase> t = thread().promote();
     if (t == nullptr) {
         return AUDIO_CHANNEL_NONE;
     }
@@ -3125,10 +3124,10 @@
         return AUDIO_CHANNEL_NONE;
     }
 
-    if (mThreadType == AudioFlinger::ThreadBase::SPATIALIZER) {
+    if (mThreadType == IAfThreadBase::SPATIALIZER) {
         if (!audio_is_global_session(c->sessionId())) {
             if ((t->hasAudioSession_l(c->sessionId())
-                    & AudioFlinger::ThreadBase::SPATIALIZED_SESSION) != 0) {
+                    & IAfThreadBase::SPATIALIZED_SESSION) != 0) {
                 return t->mixerChannelMask();
             } else {
                 return t->channelMask();
@@ -3146,7 +3145,7 @@
 }
 
 audio_channel_mask_t EffectChain::EffectCallback::hapticChannelMask() const {
-    sp<AudioFlinger::ThreadBase> t = thread().promote();
+    const sp<IAfThreadBase> t = thread().promote();
     if (t == nullptr) {
         return AUDIO_CHANNEL_NONE;
     }
@@ -3154,7 +3153,7 @@
 }
 
 size_t EffectChain::EffectCallback::frameCount() const {
-    sp<AudioFlinger::ThreadBase> t = thread().promote();
+    const sp<IAfThreadBase> t = thread().promote();
     if (t == nullptr) {
         return 0;
     }
@@ -3164,7 +3163,7 @@
 uint32_t EffectChain::EffectCallback::latency() const
 NO_THREAD_SAFETY_ANALYSIS  // latency_l() access
 {
-    sp<AudioFlinger::ThreadBase> t = thread().promote();
+    const sp<IAfThreadBase> t = thread().promote();
     if (t == nullptr) {
         return 0;
     }
@@ -3175,7 +3174,7 @@
 void EffectChain::EffectCallback::setVolumeForOutput(float left, float right) const
 NO_THREAD_SAFETY_ANALYSIS  // setVolumeForOutput_l() access
 {
-    sp<AudioFlinger::ThreadBase> t = thread().promote();
+    const sp<IAfThreadBase> t = thread().promote();
     if (t == nullptr) {
         return;
     }
@@ -3184,7 +3183,7 @@
 
 void EffectChain::EffectCallback::checkSuspendOnEffectEnabled(
         const sp<IAfEffectBase>& effect, bool enabled, bool threadLocked) {
-    sp<AudioFlinger::ThreadBase> t = thread().promote();
+    const sp<IAfThreadBase> t = thread().promote();
     if (t == nullptr) {
         return;
     }
@@ -3199,7 +3198,7 @@
 }
 
 void EffectChain::EffectCallback::onEffectEnable(const sp<IAfEffectBase>& effect) {
-    sp<AudioFlinger::ThreadBase> t = thread().promote();
+    const sp<IAfThreadBase> t = thread().promote();
     if (t == nullptr) {
         return;
     }
@@ -3210,7 +3209,7 @@
 void EffectChain::EffectCallback::onEffectDisable(const sp<IAfEffectBase>& effect) {
     checkSuspendOnEffectEnabled(effect, false, false /*threadLocked*/);
 
-    sp<AudioFlinger::ThreadBase> t = thread().promote();
+    const sp<IAfThreadBase> t = thread().promote();
     if (t == nullptr) {
         return;
     }
@@ -3219,7 +3218,7 @@
 
 bool EffectChain::EffectCallback::disconnectEffectHandle(IAfEffectHandle *handle,
                                                       bool unpinIfLast) {
-    sp<AudioFlinger::ThreadBase> t = thread().promote();
+    const sp<IAfThreadBase> t = thread().promote();
     if (t == nullptr) {
         return false;
     }
@@ -3259,11 +3258,11 @@
 /* static */
 sp<IAfDeviceEffectProxy> IAfDeviceEffectProxy::create(
         const AudioDeviceTypeAddr& device,
-        const sp</* DeviceEffectManagerCallback */ RefBase>& callback,  // TODO(b/288339104) type
+        const sp<DeviceEffectManagerCallback>& callback,
         effect_descriptor_t *desc, int id, bool notifyFramesProcessed)
 {
     return sp<DeviceEffectProxy>::make(device,
-            sp<AudioFlinger::DeviceEffectManagerCallback>::cast(callback),
+            callback,
             desc, id, notifyFramesProcessed);
 }
 
@@ -3289,7 +3288,7 @@
 }
 
 status_t DeviceEffectProxy::init(
-        const std::map <audio_patch_handle_t, AudioFlinger::PatchPanel::Patch>& patches) {
+        const std::map <audio_patch_handle_t, IAfPatchPanel::Patch>& patches) {
 //For all audio patches
 //If src or sink device match
 //If the effect is HW accelerated
@@ -3313,7 +3312,7 @@
 
 status_t DeviceEffectProxy::onUpdatePatch(audio_patch_handle_t oldPatchHandle,
         audio_patch_handle_t newPatchHandle,
-        const AudioFlinger::PatchPanel::Patch& patch __unused) {
+        const IAfPatchPanel::Patch& /* patch */) {
     status_t status = NAME_NOT_FOUND;
     ALOGV("%s", __func__);
     Mutex::Autolock _l(mProxyLock);
@@ -3329,7 +3328,7 @@
 }
 
 status_t DeviceEffectProxy::onCreatePatch(
-        audio_patch_handle_t patchHandle, const AudioFlinger::PatchPanel::Patch& patch) {
+        audio_patch_handle_t patchHandle, const IAfPatchPanel::Patch& patch) {
     status_t status = NAME_NOT_FOUND;
     sp<IAfEffectHandle> handle;
     // only consider source[0] as this is the only "true" source of a patch
@@ -3352,7 +3351,7 @@
     return status;
 }
 
-status_t DeviceEffectProxy::checkPort(const AudioFlinger::PatchPanel::Patch& patch,
+status_t DeviceEffectProxy::checkPort(const IAfPatchPanel::Patch& patch,
         const struct audio_port_config *port, sp<IAfEffectHandle> *handle) {
 
     ALOGV("%s type %d device type %d address %s device ID %d patch.isSoftware() %d",
@@ -3401,7 +3400,7 @@
             mDevicePort.id = AUDIO_PORT_HANDLE_NONE;
         }
     } else if (patch.isSoftware() || patch.thread().promote() != nullptr) {
-        sp <AudioFlinger::ThreadBase> thread;
+        sp<IAfThreadBase> thread;
         if (audio_port_config_has_input_direction(port)) {
             if (patch.isSoftware()) {
                 thread = patch.mRecord.thread();
diff --git a/services/audioflinger/Effects.h b/services/audioflinger/Effects.h
index 4f4df53..365cd45 100644
--- a/services/audioflinger/Effects.h
+++ b/services/audioflinger/Effects.h
@@ -382,7 +382,7 @@
 // it also provide it's own input buffer used by the track as accumulation buffer.
 class EffectChain : public IAfEffectChain {
 public:
-    EffectChain(const wp<AudioFlinger::ThreadBase>& wThread, audio_session_t sessionId);
+    EffectChain(const wp<IAfThreadBase>& wThread, audio_session_t sessionId);
     ~EffectChain() override;
 
     void process_l() final;
@@ -479,12 +479,7 @@
     bool isBitPerfectCompatible() const final;
 
     // isCompatibleWithThread_l() must be called with thread->mLock held
-    // TODO(b/288339104) type
-    bool isCompatibleWithThread_l(const sp<Thread>& thread) const final {
-        return isCompatibleWithThread_l(sp<AudioFlinger::ThreadBase>::cast(thread));
-    }
-
-    bool isCompatibleWithThread_l(const sp<AudioFlinger::ThreadBase>& thread) const;
+    bool isCompatibleWithThread_l(const sp<IAfThreadBase>& thread) const final;
 
     bool containsHapticGeneratingEffect_l() final;
 
@@ -492,8 +487,7 @@
 
     sp<EffectCallbackInterface> effectCallback() const final { return mEffectCallback; }
 
-    // TODO(b/288339104) type
-    wp<Thread> thread() const final { return mEffectCallback->thread(); }
+    wp<IAfThreadBase> thread() const final { return mEffectCallback->thread(); }
 
     bool isFirstEffect(int id) const final {
         return !mEffects.isEmpty() && id == mEffects[0]->id();
@@ -507,12 +501,7 @@
         return mEffects[index];
     }
 
-    // TODO(b/288339104) type
-    void setThread(const sp<Thread>& thread) final {
-        setThread(sp<AudioFlinger::ThreadBase>::cast(thread));
-    }
-
-    void setThread(const sp<AudioFlinger::ThreadBase>& thread);
+    void setThread(const sp<IAfThreadBase>& thread) final;
 
 private:
 
@@ -527,15 +516,15 @@
         // Note: ctors taking a weak pointer to their owner must not promote it
         // during construction (but may keep a reference for later promotion).
         EffectCallback(const wp<EffectChain>& owner,
-                       const wp<AudioFlinger::ThreadBase>& thread)
+                const wp<IAfThreadBase>& thread)
             : mChain(owner)
             , mThread(thread)
             , mAudioFlinger(*AudioFlinger::gAudioFlinger) {
-            sp<AudioFlinger::ThreadBase> base = thread.promote();
+            const sp<IAfThreadBase> base = thread.promote();
             if (base != nullptr) {
                 mThreadType = base->type();
             } else {
-                mThreadType = AudioFlinger::ThreadBase::MIXER;  // assure a consistent value.
+                mThreadType = IAfThreadBase::MIXER;  // assure a consistent value.
             }
         }
 
@@ -580,18 +569,18 @@
             return mAudioFlinger.isAudioPolicyReady();
         }
 
-        wp<AudioFlinger::ThreadBase> thread() const { return mThread.load(); }
+        wp<IAfThreadBase> thread() const { return mThread.load(); }
 
-        void setThread(const sp<AudioFlinger::ThreadBase>& thread) {
+        void setThread(const sp<IAfThreadBase>& thread) {
             mThread = thread;
             mThreadType = thread->type();
         }
 
     private:
         const wp<IAfEffectChain> mChain;
-        mediautils::atomic_wp<AudioFlinger::ThreadBase> mThread;
+        mediautils::atomic_wp<IAfThreadBase> mThread;
         AudioFlinger &mAudioFlinger;  // implementation detail: outer instance always exists.
-        AudioFlinger::ThreadBase::type_t mThreadType;
+        IAfThreadBase::type_t mThreadType;
     };
 
     DISALLOW_COPY_AND_ASSIGN(EffectChain);
@@ -657,7 +646,7 @@
 class DeviceEffectProxy : public IAfDeviceEffectProxy, public EffectBase {
 public:
     DeviceEffectProxy(const AudioDeviceTypeAddr& device,
-                const sp<AudioFlinger::DeviceEffectManagerCallback>& callback,
+            const sp<DeviceEffectManagerCallback>& callback,
                 effect_descriptor_t *desc, int id, bool notifyFramesProcessed)
             : EffectBase(callback, desc, id, AUDIO_SESSION_DEVICE, false),
                 mDevice(device), mManagerCallback(callback),
@@ -667,31 +656,14 @@
     status_t setEnabled(bool enabled, bool fromHandle) final;
     sp<IAfDeviceEffectProxy> asDeviceEffectProxy() final { return this; }
 
-    // TODO(b/288339104) type
-    status_t init(const /* std::map<audio_patch_handle_t,
-            PatchPanel::Patch>& */ void * patches) final {
-        return init(*reinterpret_cast<const std::map<
-                audio_patch_handle_t, AudioFlinger::PatchPanel::Patch> *>(patches));
-    }
-    // TODO(b/288339104) type
+    status_t init(const std::map<audio_patch_handle_t,
+            IAfPatchPanel::Patch>& patches) final;
+
     status_t onCreatePatch(audio_patch_handle_t patchHandle,
-            /* const PatchPanel::Patch& */ const void * patch) final {
-        return onCreatePatch(patchHandle,
-                *reinterpret_cast<const AudioFlinger::PatchPanel::Patch *>(patch));
-    }
-    // TODO(b/288339104) type
-    status_t onUpdatePatch(audio_patch_handle_t oldPatchHandle, audio_patch_handle_t newPatchHandle,
-            /* const PatchPanel::Patch& */ const void * patch) final {
-        return onUpdatePatch(oldPatchHandle, newPatchHandle,
-                *reinterpret_cast<const AudioFlinger::PatchPanel::Patch *>(patch));
-    }
-
-    status_t init(const std::map<audio_patch_handle_t, AudioFlinger::PatchPanel::Patch>& patches);
-    status_t onCreatePatch(
-            audio_patch_handle_t patchHandle, const AudioFlinger::PatchPanel::Patch& patch);
+            const IAfPatchPanel::Patch& patch) final;
 
     status_t onUpdatePatch(audio_patch_handle_t oldPatchHandle, audio_patch_handle_t newPatchHandle,
-            const AudioFlinger::PatchPanel::Patch& patch);
+           const IAfPatchPanel::Patch& patch) final;
 
     void onReleasePatch(audio_patch_handle_t patchHandle) final;
 
@@ -720,7 +692,7 @@
         // Note: ctors taking a weak pointer to their owner must not promote it
         // during construction (but may keep a reference for later promotion).
         ProxyCallback(const wp<DeviceEffectProxy>& owner,
-                const sp<AudioFlinger::DeviceEffectManagerCallback>& callback)
+                const sp<DeviceEffectManagerCallback>& callback)
             : mProxy(owner), mManagerCallback(callback) {}
 
         status_t createEffectHal(const effect_uuid_t *pEffectUuid,
@@ -771,14 +743,14 @@
 
     private:
         const wp<DeviceEffectProxy> mProxy;
-        const sp<AudioFlinger::DeviceEffectManagerCallback> mManagerCallback;
+        const sp<DeviceEffectManagerCallback> mManagerCallback;
     };
 
-    status_t checkPort(const AudioFlinger::PatchPanel::Patch& patch,
+    status_t checkPort(const IAfPatchPanel::Patch& patch,
             const struct audio_port_config *port, sp<IAfEffectHandle> *handle);
 
     const AudioDeviceTypeAddr mDevice;
-    const sp<AudioFlinger::DeviceEffectManagerCallback> mManagerCallback;
+    const sp<DeviceEffectManagerCallback> mManagerCallback;
     const sp<ProxyCallback> mMyCallback;
 
     mutable Mutex mProxyLock;
diff --git a/services/audioflinger/IAfEffect.h b/services/audioflinger/IAfEffect.h
index 29f1862..ece0081 100644
--- a/services/audioflinger/IAfEffect.h
+++ b/services/audioflinger/IAfEffect.h
@@ -18,11 +18,13 @@
 
 namespace android {
 
+class DeviceEffectManagerCallback;
 class IAfDeviceEffectProxy;
 class IAfEffectBase;
 class IAfEffectChain;
 class IAfEffectHandle;
 class IAfEffectModule;
+class IAfThreadBase;
 
 // Interface implemented by the EffectModule parent or owner (e.g an EffectChain) to abstract
 // interactions between the EffectModule and the reset of the audio framework.
@@ -190,7 +192,7 @@
     // Most of these methods are accessed from AudioFlinger::Thread
 public:
     static sp<IAfEffectChain> create(
-            const wp<Thread /*ThreadBase*/>& wThread,  // TODO(b/288339104) type
+            const wp<IAfThreadBase>& wThread,
             audio_session_t sessionId);
 
     // special key used for an entry in mSuspendedEffects keyed vector
@@ -279,8 +281,7 @@
     virtual bool isBitPerfectCompatible() const = 0;
 
     // isCompatibleWithThread_l() must be called with thread->mLock held
-    //  TODO(b/288339104) type
-    virtual bool isCompatibleWithThread_l(const sp<Thread>& thread) const = 0;
+    virtual bool isCompatibleWithThread_l(const sp<IAfThreadBase>& thread) const = 0;
 
     virtual bool containsHapticGeneratingEffect_l() = 0;
 
@@ -288,8 +289,8 @@
 
     virtual sp<EffectCallbackInterface> effectCallback() const = 0;
 
-    virtual wp<Thread> thread() const = 0;  // TODO(b/288339104) type
-    virtual void setThread(const sp<Thread>& thread) = 0;  // TODO(b/288339104) type
+    virtual wp<IAfThreadBase> thread() const = 0;
+    virtual void setThread(const sp<IAfThreadBase>& thread) = 0;
 
     virtual bool isFirstEffect(int id) const = 0;
 
@@ -335,25 +336,24 @@
 
 class IAfDeviceEffectProxy : public virtual IAfEffectBase {
 public:
-    // TODO(b/288339104) type
     static sp<IAfDeviceEffectProxy> create(const AudioDeviceTypeAddr& device,
-                const sp</* DeviceEffectManagerCallback */ RefBase>& callback,
+                const sp<DeviceEffectManagerCallback>& callback,
                 effect_descriptor_t *desc, int id, bool notifyFramesProcessed);
 
     virtual status_t init(
-            const /* std::map<audio_patch_handle_t,
-            PatchPanel::Patch>& */ void * patches) = 0; // TODO(b/288339104) type
+            const std::map<audio_patch_handle_t,
+            IAfPatchPanel::Patch>& patches) = 0;
     virtual const AudioDeviceTypeAddr& device() const = 0;
 
     virtual status_t onCreatePatch(
             audio_patch_handle_t patchHandle,
-            /* const PatchPanel::Patch& */ const void * patch) = 0;
+            const IAfPatchPanel::Patch& patch) = 0;
     virtual status_t onUpdatePatch(audio_patch_handle_t oldPatchHandle,
             audio_patch_handle_t newPatchHandle,
-            /* const PatchPanel::Patch& */ const void * patch) = 0;
+            const IAfPatchPanel::Patch& patch) = 0;
     virtual void onReleasePatch(audio_patch_handle_t patchHandle) = 0;
 
-    virtual void dump2(int fd, int spaces) const = 0; // TODO(b/288339104) naming?
+    virtual void dump2(int fd, int spaces) const = 0; // TODO(b/291319101) naming?
 
 private:
     // used by DeviceEffectProxy
@@ -367,4 +367,4 @@
     virtual status_t removeEffectFromHal(const sp<EffectHalInterface>& effect) = 0;
 };
 
-} // namespace android
+}  // namespace android
diff --git a/services/audioflinger/IAfPatchPanel.h b/services/audioflinger/IAfPatchPanel.h
new file mode 100644
index 0000000..29bd4ab
--- /dev/null
+++ b/services/audioflinger/IAfPatchPanel.h
@@ -0,0 +1,251 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+namespace android {
+
+class IAfPatchPanel;
+class IAfPatchRecord;
+class IAfPatchTrack;
+class IAfPlaybackThread;
+class IAfRecordThread;
+class IAfThreadBase;
+
+class SoftwarePatch {
+public:
+    SoftwarePatch(
+            const sp<const IAfPatchPanel>& patchPanel,
+            audio_patch_handle_t patchHandle,
+            audio_io_handle_t playbackThreadHandle,
+            audio_io_handle_t recordThreadHandle)
+        : mPatchPanel(patchPanel),
+          mPatchHandle(patchHandle),
+          mPlaybackThreadHandle(playbackThreadHandle),
+          mRecordThreadHandle(recordThreadHandle) {}
+    SoftwarePatch(const SoftwarePatch&) = default;
+
+    // Must be called under AudioFlinger::mLock
+    status_t getLatencyMs_l(double* latencyMs) const;
+    audio_patch_handle_t getPatchHandle() const { return mPatchHandle; };
+    audio_io_handle_t getPlaybackThreadHandle() const { return mPlaybackThreadHandle; };
+    audio_io_handle_t getRecordThreadHandle() const { return mRecordThreadHandle; };
+
+private:
+    const sp<const IAfPatchPanel> mPatchPanel;
+    const audio_patch_handle_t mPatchHandle;
+    const audio_io_handle_t mPlaybackThreadHandle;
+    const audio_io_handle_t mRecordThreadHandle;
+};
+
+class IAfPatchPanel : public virtual RefBase {
+public:
+    static sp<IAfPatchPanel> create(AudioFlinger* audioFlinger);
+
+    // Extraction of inner Endpoint and Patch classes would require interfaces
+    // (in the Endpoint case a templated interface) but that seems
+    // excessive for now.  We keep them as inner classes until extraction
+    // is needed.
+    template <typename ThreadType, typename TrackType>
+    class Endpoint final {
+    public:
+        Endpoint() = default;
+        Endpoint(const Endpoint&) = delete;
+        Endpoint& operator=(const Endpoint& other) noexcept {
+            mThread = other.mThread;
+            mCloseThread = other.mCloseThread;
+            mHandle = other.mHandle;
+            mTrack = other.mTrack;
+            return *this;
+        }
+        Endpoint(Endpoint&& other) noexcept { swap(other); }
+        Endpoint& operator=(Endpoint&& other) noexcept {
+            swap(other);
+            return *this;
+        }
+        ~Endpoint() {
+            ALOGE_IF(
+                    mHandle != AUDIO_PATCH_HANDLE_NONE,
+                    "A non empty Patch Endpoint leaked, handle %d", mHandle);
+        }
+
+        status_t checkTrack(TrackType* trackOrNull) const {
+            if (trackOrNull == nullptr) return NO_MEMORY;
+            return trackOrNull->initCheck();
+        }
+        audio_patch_handle_t handle() const { return mHandle; }
+        sp<ThreadType> thread() const { return mThread; }
+        sp<TrackType> track() const { return mTrack; }
+        sp<const ThreadType> const_thread() const { return mThread; }
+        sp<const TrackType> const_track() const { return mTrack; }
+
+        void closeConnections(const sp<IAfPatchPanel>& panel) {
+            if (mHandle != AUDIO_PATCH_HANDLE_NONE) {
+                panel->releaseAudioPatch(mHandle);
+                mHandle = AUDIO_PATCH_HANDLE_NONE;
+            }
+            if (mThread != nullptr) {
+                if (mTrack != nullptr) {
+                    mThread->deletePatchTrack(mTrack);
+                }
+                if (mCloseThread) {
+                    panel->closeThreadInternal_l(mThread);
+                }
+            }
+        }
+        audio_patch_handle_t* handlePtr() { return &mHandle; }
+        void setThread(const sp<ThreadType>& thread, bool closeThread = true) {
+            mThread = thread;
+            mCloseThread = closeThread;
+        }
+        template <typename T>
+        void setTrackAndPeer(const sp<TrackType>& track, const sp<T>& peer, bool holdReference) {
+            mTrack = track;
+            mThread->addPatchTrack(mTrack);
+            mTrack->setPeerProxy(peer, holdReference);
+            mClearPeerProxy = holdReference;
+        }
+        void clearTrackPeer() {
+            if (mClearPeerProxy && mTrack) mTrack->clearPeerProxy();
+        }
+        void stopTrack() {
+            if (mTrack) mTrack->stop();
+        }
+
+        void swap(Endpoint& other) noexcept {
+            using std::swap;
+            swap(mThread, other.mThread);
+            swap(mCloseThread, other.mCloseThread);
+            swap(mClearPeerProxy, other.mClearPeerProxy);
+            swap(mHandle, other.mHandle);
+            swap(mTrack, other.mTrack);
+        }
+
+        friend void swap(Endpoint& a, Endpoint& b) noexcept { a.swap(b); }
+
+    private:
+        sp<ThreadType> mThread;
+        bool mCloseThread = true;
+        bool mClearPeerProxy = true;
+        audio_patch_handle_t mHandle = AUDIO_PATCH_HANDLE_NONE;
+        sp<TrackType> mTrack;
+    };
+
+    class Patch final {
+    public:
+        Patch(const struct audio_patch& patch, bool endpointPatch)
+            : mAudioPatch(patch), mIsEndpointPatch(endpointPatch) {}
+        Patch() = default;
+        ~Patch();
+        Patch(const Patch& other) noexcept {
+            mAudioPatch = other.mAudioPatch;
+            mHalHandle = other.mHalHandle;
+            mPlayback = other.mPlayback;
+            mRecord = other.mRecord;
+            mThread = other.mThread;
+            mIsEndpointPatch = other.mIsEndpointPatch;
+        }
+        Patch(Patch&& other) noexcept { swap(other); }
+        Patch& operator=(Patch&& other) noexcept {
+            swap(other);
+            return *this;
+        }
+
+        void swap(Patch& other) noexcept {
+            using std::swap;
+            swap(mAudioPatch, other.mAudioPatch);
+            swap(mHalHandle, other.mHalHandle);
+            swap(mPlayback, other.mPlayback);
+            swap(mRecord, other.mRecord);
+            swap(mThread, other.mThread);
+            swap(mIsEndpointPatch, other.mIsEndpointPatch);
+        }
+
+        friend void swap(Patch& a, Patch& b) noexcept { a.swap(b); }
+
+        status_t createConnections(const sp<IAfPatchPanel>& panel);
+        void clearConnections(const sp<IAfPatchPanel>& panel);
+        bool isSoftware() const {
+            return mRecord.handle() != AUDIO_PATCH_HANDLE_NONE ||
+                   mPlayback.handle() != AUDIO_PATCH_HANDLE_NONE;
+        }
+
+        void setThread(const sp<IAfThreadBase>& thread) { mThread = thread; }
+        wp<IAfThreadBase> thread() const { return mThread; }
+
+        // returns the latency of the patch (from record to playback).
+        status_t getLatencyMs(double* latencyMs) const;
+
+        String8 dump(audio_patch_handle_t myHandle) const;
+
+        // Note that audio_patch::id is only unique within a HAL module
+        struct audio_patch mAudioPatch;
+        // handle for audio HAL patch handle present only when the audio HAL version is >= 3.0
+        audio_patch_handle_t mHalHandle = AUDIO_PATCH_HANDLE_NONE;
+        // below members are used by a software audio patch connecting a source device from a
+        // given audio HW module to a sink device on an other audio HW module.
+        // the objects are created by createConnections() and released by clearConnections()
+        // playback thread is created if no existing playback thread can be used
+        // connects playback thread output to sink device
+        Endpoint<IAfPlaybackThread, IAfPatchTrack> mPlayback;
+        // connects source device to record thread input
+        Endpoint<IAfRecordThread, IAfPatchRecord> mRecord;
+
+        wp<IAfThreadBase> mThread;
+        bool mIsEndpointPatch;
+    };
+
+    /* List connected audio ports and their attributes */
+    virtual status_t listAudioPorts(unsigned int* num_ports, struct audio_port* ports) = 0;
+
+    /* Get supported attributes for a given audio port */
+    virtual status_t getAudioPort(struct audio_port_v7* port) = 0;
+
+    /* Create a patch between several source and sink ports */
+    virtual status_t createAudioPatch(
+            const struct audio_patch* patch,
+            audio_patch_handle_t* handle,
+            bool endpointPatch = false) = 0;
+
+    /* Release a patch */
+    virtual status_t releaseAudioPatch(audio_patch_handle_t handle) = 0;
+
+    /* List connected audio devices and they attributes */
+    virtual status_t listAudioPatches(unsigned int* num_patches, struct audio_patch* patches) = 0;
+
+    // Retrieves all currently estrablished software patches for a stream
+    // opened on an intermediate module.
+    virtual status_t getDownstreamSoftwarePatches(
+            audio_io_handle_t stream, std::vector<SoftwarePatch>* patches) const = 0;
+
+    // Notifies patch panel about all opened and closed streams.
+    virtual void notifyStreamOpened(
+            AudioHwDevice* audioHwDevice, audio_io_handle_t stream, struct audio_patch* patch) = 0;
+
+    virtual void notifyStreamClosed(audio_io_handle_t stream) = 0;
+
+    virtual void dump(int fd) const = 0;
+
+    // Must be called under AudioFlinger::mLock
+
+    virtual const std::map<audio_patch_handle_t, Patch>& patches_l() const = 0;
+
+    virtual status_t getLatencyMs_l(audio_patch_handle_t patchHandle, double* latencyMs) const = 0;
+
+    virtual void closeThreadInternal_l(const sp<IAfThreadBase>& thread) const = 0;
+};
+
+}  // namespace android
diff --git a/services/audioflinger/IAfThread.h b/services/audioflinger/IAfThread.h
new file mode 100644
index 0000000..ce4d62d
--- /dev/null
+++ b/services/audioflinger/IAfThread.h
@@ -0,0 +1,517 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include "IAfTrack.h"
+
+namespace android {
+
+class IAfDirectOutputThread;
+class IAfDuplicatingThread;
+class IAfMmapCaptureThread;
+class IAfMmapPlaybackThread;
+class IAfPlaybackThread;
+class IAfRecordThread;
+
+class IAfThreadBase : public virtual RefBase {
+public:
+    enum type_t {
+        MIXER,          // Thread class is MixerThread
+        DIRECT,         // Thread class is DirectOutputThread
+        DUPLICATING,    // Thread class is DuplicatingThread
+        RECORD,         // Thread class is RecordThread
+        OFFLOAD,        // Thread class is OffloadThread
+        MMAP_PLAYBACK,  // Thread class for MMAP playback stream
+        MMAP_CAPTURE,   // Thread class for MMAP capture stream
+        SPATIALIZER,    //
+        BIT_PERFECT,    // Thread class for BitPerfectThread
+        // When adding a value, also update IAfThreadBase::threadTypeToString()
+    };
+
+    static const char* threadTypeToString(type_t type);
+    virtual status_t readyToRun() = 0;
+    virtual void clearPowerManager() = 0;
+    virtual status_t initCheck() const = 0;
+    virtual type_t type() const = 0;
+    virtual bool isDuplicating() const = 0;
+    virtual audio_io_handle_t id() const = 0;
+    virtual uint32_t sampleRate() const = 0;
+    virtual audio_channel_mask_t channelMask() const = 0;
+    virtual audio_channel_mask_t mixerChannelMask() const = 0;
+    virtual audio_format_t format() const = 0;
+    virtual uint32_t channelCount() const = 0;
+
+    // Called by AudioFlinger::frameCount(audio_io_handle_t output) and effects,
+    // and returns the [normal mix] buffer's frame count.
+    virtual size_t frameCount() const = 0;
+    virtual audio_channel_mask_t hapticChannelMask() const = 0;
+    virtual uint32_t hapticChannelCount() const = 0;
+    virtual uint32_t latency_l() const = 0;
+    virtual void setVolumeForOutput_l(float left, float right) const = 0;
+
+    // Return's the HAL's frame count i.e. fast mixer buffer size.
+    virtual size_t frameCountHAL() const = 0;
+    virtual size_t frameSize() const = 0;
+    // Should be "virtual status_t requestExitAndWait()" and override same
+    // method in Thread, but Thread::requestExitAndWait() is not yet virtual.
+    virtual void exit() = 0;
+    virtual bool checkForNewParameter_l(const String8& keyValuePair, status_t& status) = 0;
+    virtual status_t setParameters(const String8& keyValuePairs) = 0;
+    virtual String8 getParameters(const String8& keys) = 0;
+    virtual void ioConfigChanged(
+            audio_io_config_event_t event, pid_t pid = 0,
+            audio_port_handle_t portId = AUDIO_PORT_HANDLE_NONE) = 0;
+
+    // sendConfigEvent_l() must be called with ThreadBase::mLock held
+    // Can temporarily release the lock if waiting for a reply from
+    // processConfigEvents_l().
+    // status_t sendConfigEvent_l(sp<ConfigEvent>& event);
+    virtual void sendIoConfigEvent(
+            audio_io_config_event_t event, pid_t pid = 0,
+            audio_port_handle_t portId = AUDIO_PORT_HANDLE_NONE) = 0;
+    virtual void sendIoConfigEvent_l(
+            audio_io_config_event_t event, pid_t pid = 0,
+            audio_port_handle_t portId = AUDIO_PORT_HANDLE_NONE) = 0;
+    virtual void sendPrioConfigEvent(pid_t pid, pid_t tid, int32_t prio, bool forApp) = 0;
+    virtual void sendPrioConfigEvent_l(pid_t pid, pid_t tid, int32_t prio, bool forApp) = 0;
+    virtual status_t sendSetParameterConfigEvent_l(const String8& keyValuePair) = 0;
+    virtual status_t sendCreateAudioPatchConfigEvent(
+            const struct audio_patch* patch, audio_patch_handle_t* handle) = 0;
+    virtual status_t sendReleaseAudioPatchConfigEvent(audio_patch_handle_t handle) = 0;
+    virtual status_t sendUpdateOutDeviceConfigEvent(
+            const DeviceDescriptorBaseVector& outDevices) = 0;
+    virtual void sendResizeBufferConfigEvent_l(int32_t maxSharedAudioHistoryMs) = 0;
+    virtual void sendCheckOutputStageEffectsEvent() = 0;
+    virtual void sendCheckOutputStageEffectsEvent_l() = 0;
+    virtual void sendHalLatencyModesChangedEvent_l() = 0;
+
+    virtual void processConfigEvents_l() = 0;
+    virtual void setCheckOutputStageEffects() = 0;
+    virtual void cacheParameters_l() = 0;
+    virtual status_t createAudioPatch_l(
+            const struct audio_patch* patch, audio_patch_handle_t* handle) = 0;
+    virtual status_t releaseAudioPatch_l(const audio_patch_handle_t handle) = 0;
+    virtual void updateOutDevices(const DeviceDescriptorBaseVector& outDevices) = 0;
+    virtual void toAudioPortConfig(struct audio_port_config* config) = 0;
+    virtual void resizeInputBuffer_l(int32_t maxSharedAudioHistoryMs) = 0;
+
+    // see note at declaration of mStandby, mOutDevice and mInDevice
+    virtual bool inStandby() const = 0;
+    virtual const DeviceTypeSet outDeviceTypes() const = 0;
+    virtual audio_devices_t inDeviceType() const = 0;
+    virtual DeviceTypeSet getDeviceTypes() const = 0;
+    virtual const AudioDeviceTypeAddrVector& outDeviceTypeAddrs() const = 0;
+    virtual const AudioDeviceTypeAddr& inDeviceTypeAddr() const = 0;
+    virtual bool isOutput() const = 0;
+    virtual bool isOffloadOrMmap() const = 0;
+    virtual sp<StreamHalInterface> stream() const = 0;
+    virtual sp<IAfEffectHandle> createEffect_l(
+            const sp<Client>& client,
+            const sp<media::IEffectClient>& effectClient,
+            int32_t priority,
+            audio_session_t sessionId,
+            effect_descriptor_t* desc,
+            int* enabled,
+            status_t* status /*non-NULL*/,
+            bool pinned,
+            bool probe,
+            bool notifyFramesProcessed) = 0;
+
+    // return values for hasAudioSession (bit field)
+    enum effect_state {
+        EFFECT_SESSION = 0x1,       // the audio session corresponds to at least one
+                                    // effect
+        TRACK_SESSION = 0x2,        // the audio session corresponds to at least one
+                                    // track
+        FAST_SESSION = 0x4,         // the audio session corresponds to at least one
+                                    // fast track
+        SPATIALIZED_SESSION = 0x8,  // the audio session corresponds to at least one
+                                    // spatialized track
+        BIT_PERFECT_SESSION = 0x10  // the audio session corresponds to at least one
+                                    // bit-perfect track
+    };
+
+    // get effect chain corresponding to session Id.
+    virtual sp<IAfEffectChain> getEffectChain(audio_session_t sessionId) const = 0;
+    // same as getEffectChain() but must be called with ThreadBase mutex locked
+    virtual sp<IAfEffectChain> getEffectChain_l(audio_session_t sessionId) const = 0;
+    virtual std::vector<int> getEffectIds_l(audio_session_t sessionId) const = 0;
+    // add an effect chain to the chain list (mEffectChains)
+    virtual status_t addEffectChain_l(const sp<IAfEffectChain>& chain) = 0;
+    // remove an effect chain from the chain list (mEffectChains)
+    virtual size_t removeEffectChain_l(const sp<IAfEffectChain>& chain) = 0;
+    // lock all effect chains Mutexes. Must be called before releasing the
+    // ThreadBase mutex before processing the mixer and effects. This guarantees the
+    // integrity of the chains during the process.
+    // Also sets the parameter 'effectChains' to current value of mEffectChains.
+    virtual void lockEffectChains_l(Vector<sp<IAfEffectChain>>& effectChains) = 0;
+    // unlock effect chains after process
+    virtual void unlockEffectChains(const Vector<sp<IAfEffectChain>>& effectChains) = 0;
+    // get a copy of mEffectChains vector
+    virtual Vector<sp<IAfEffectChain>> getEffectChains_l() const = 0;
+    // set audio mode to all effect chains
+    virtual void setMode(audio_mode_t mode) = 0;
+    // get effect module with corresponding ID on specified audio session
+    virtual sp<IAfEffectModule> getEffect(audio_session_t sessionId, int effectId) const = 0;
+    virtual sp<IAfEffectModule> getEffect_l(audio_session_t sessionId, int effectId) const = 0;
+    // add and effect module. Also creates the effect chain is none exists for
+    // the effects audio session. Only called in a context of moving an effect
+    // from one thread to another
+    virtual status_t addEffect_l(const sp<IAfEffectModule>& effect) = 0;
+    // remove and effect module. Also removes the effect chain is this was the last
+    // effect
+    virtual void removeEffect_l(const sp<IAfEffectModule>& effect, bool release = false) = 0;
+    // disconnect an effect handle from module and destroy module if last handle
+    virtual void disconnectEffectHandle(IAfEffectHandle* handle, bool unpinIfLast) = 0;
+    // detach all tracks connected to an auxiliary effect
+    virtual void detachAuxEffect_l(int effectId) = 0;
+    // returns a combination of:
+    // - EFFECT_SESSION if effects on this audio session exist in one chain
+    // - TRACK_SESSION if tracks on this audio session exist
+    // - FAST_SESSION if fast tracks on this audio session exist
+    // - SPATIALIZED_SESSION if spatialized tracks on this audio session exist
+    virtual uint32_t hasAudioSession_l(audio_session_t sessionId) const = 0;
+    virtual uint32_t hasAudioSession(audio_session_t sessionId) const = 0;
+
+    // the value returned by default implementation is not important as the
+    // strategy is only meaningful for PlaybackThread which implements this method
+    virtual product_strategy_t getStrategyForSession_l(audio_session_t sessionId) const = 0;
+
+    // check if some effects must be suspended/restored when an effect is enabled
+    // or disabled
+    virtual void checkSuspendOnEffectEnabled(
+            bool enabled, audio_session_t sessionId, bool threadLocked) = 0;
+
+    virtual status_t setSyncEvent(const sp<audioflinger::SyncEvent>& event) = 0;
+    virtual bool isValidSyncEvent(const sp<audioflinger::SyncEvent>& event) const = 0;
+
+    // Return a reference to a per-thread heap which can be used to allocate IMemory
+    // objects that will be read-only to client processes, read/write to mediaserver,
+    // and shared by all client processes of the thread.
+    // The heap is per-thread rather than common across all threads, because
+    // clients can't be trusted not to modify the offset of the IMemory they receive.
+    // If a thread does not have such a heap, this method returns 0.
+    virtual sp<MemoryDealer> readOnlyHeap() const = 0;
+
+    virtual sp<IMemory> pipeMemory() const = 0;
+
+    virtual void systemReady() = 0;
+
+    // checkEffectCompatibility_l() must be called with ThreadBase::mLock held
+    virtual status_t checkEffectCompatibility_l(
+            const effect_descriptor_t* desc, audio_session_t sessionId) = 0;
+
+    virtual void broadcast_l() = 0;
+
+    virtual bool isTimestampCorrectionEnabled() const = 0;
+
+    virtual bool isMsdDevice() const = 0;
+
+    virtual void dump(int fd, const Vector<String16>& args) = 0;
+
+    // deliver stats to mediametrics.
+    virtual void sendStatistics(bool force) = 0;
+
+    virtual Mutex& mutex() const = 0;
+
+    virtual void onEffectEnable(const sp<IAfEffectModule>& effect) = 0;
+    virtual void onEffectDisable() = 0;
+
+    // invalidateTracksForAudioSession_l must be called with holding mLock.
+    virtual void invalidateTracksForAudioSession_l(audio_session_t sessionId) const = 0;
+    // Invalidate all the tracks with the given audio session.
+    virtual void invalidateTracksForAudioSession(audio_session_t sessionId) const = 0;
+
+    virtual bool isStreamInitialized() const = 0;
+    virtual void startMelComputation_l(const sp<audio_utils::MelProcessor>& processor) = 0;
+    virtual void stopMelComputation_l() = 0;
+
+    virtual product_strategy_t getStrategyForStream(audio_stream_type_t stream) const = 0;
+
+    virtual void setEffectSuspended_l(
+            const effect_uuid_t* type, bool suspend, audio_session_t sessionId) = 0;
+
+    // Dynamic cast to derived interface
+    virtual sp<IAfDirectOutputThread> asIAfDirectOutputThread() { return nullptr; }
+    virtual sp<IAfDuplicatingThread> asIAfDuplicatingThread() { return nullptr; }
+    virtual sp<IAfPlaybackThread> asIAfPlaybackThread() { return nullptr; }
+    virtual sp<IAfRecordThread> asIAfRecordThread() { return nullptr; }
+    virtual AudioFlinger* audioFlinger() const = 0;
+};
+
+class IAfPlaybackThread : public virtual IAfThreadBase, public virtual VolumeInterface {
+public:
+    static sp<IAfPlaybackThread> createBitPerfectThread(
+            const sp<AudioFlinger>& audioflinger, AudioStreamOut* output, audio_io_handle_t id,
+            bool systemReady);
+
+    static sp<IAfPlaybackThread> createDirectOutputThread(
+            const sp<AudioFlinger>& audioFlinger, AudioStreamOut* output, audio_io_handle_t id,
+            bool systemReady, const audio_offload_info_t& offloadInfo);
+
+    static sp<IAfPlaybackThread> createMixerThread(
+            const sp<AudioFlinger>& audioFlinger, AudioStreamOut* output, audio_io_handle_t id,
+            bool systemReady, type_t type = MIXER, audio_config_base_t* mixerConfig = nullptr);
+
+    static sp<IAfPlaybackThread> createOffloadThread(
+            const sp<AudioFlinger>& audioFlinger, AudioStreamOut* output, audio_io_handle_t id,
+            bool systemReady, const audio_offload_info_t& offloadInfo);
+
+    static sp<IAfPlaybackThread> createSpatializerThread(
+            const sp<AudioFlinger>& audioFlinger, AudioStreamOut* output, audio_io_handle_t id,
+            bool systemReady, audio_config_base_t* mixerConfig);
+
+    static constexpr int8_t kMaxTrackStopRetriesOffload = 2;
+
+    enum mixer_state {
+        MIXER_IDLE,            // no active tracks
+        MIXER_TRACKS_ENABLED,  // at least one active track, but no track has any data ready
+        MIXER_TRACKS_READY,    // at least one active track, and at least one track has data
+        MIXER_DRAIN_TRACK,     // drain currently playing track
+        MIXER_DRAIN_ALL,       // fully drain the hardware
+        // standby mode does not have an enum value
+        // suspend by audio policy manager is orthogonal to mixer state
+    };
+
+    // return estimated latency in milliseconds, as reported by HAL
+    virtual uint32_t latency() const = 0;  // should be in IAfThreadBase?
+
+    virtual uint32_t& fastTrackAvailMask_l() = 0;
+
+    virtual sp<IAfTrack> createTrack_l(
+            const sp<Client>& client,
+            audio_stream_type_t streamType,
+            const audio_attributes_t& attr,
+            uint32_t* sampleRate,
+            audio_format_t format,
+            audio_channel_mask_t channelMask,
+            size_t* pFrameCount,
+            size_t* pNotificationFrameCount,
+            uint32_t notificationsPerBuffer,
+            float speed,
+            const sp<IMemory>& sharedBuffer,
+            audio_session_t sessionId,
+            audio_output_flags_t* flags,
+            pid_t creatorPid,
+            const AttributionSourceState& attributionSource,
+            pid_t tid,
+            status_t* status /*non-NULL*/,
+            audio_port_handle_t portId,
+            const sp<media::IAudioTrackCallback>& callback,
+            bool isSpatialized,
+            bool isBitPerfect) = 0;
+
+    virtual status_t addTrack_l(const sp<IAfTrack>& track) = 0;
+    virtual bool destroyTrack_l(const sp<IAfTrack>& track) = 0;
+    virtual bool isTrackActive(const sp<IAfTrack>& track) const = 0;
+    virtual void addOutputTrack_l(const sp<IAfTrack>& track) = 0;
+
+    virtual AudioStreamOut* getOutput_l() const = 0;
+    virtual AudioStreamOut* getOutput() const = 0;
+    virtual AudioStreamOut* clearOutput() = 0;
+
+    // a very large number of suspend() will eventually wraparound, but unlikely
+    virtual void suspend() = 0;
+    virtual void restore() = 0;
+    virtual bool isSuspended() const = 0;
+    virtual status_t getRenderPosition(uint32_t* halFrames, uint32_t* dspFrames) const = 0;
+    // Consider also removing and passing an explicit mMainBuffer initialization
+    // parameter to AF::IAfTrack::Track().
+    virtual float* sinkBuffer() const = 0;
+
+    virtual status_t attachAuxEffect(const sp<IAfTrack>& track, int EffectId) = 0;
+    virtual status_t attachAuxEffect_l(const sp<IAfTrack>& track, int EffectId) = 0;
+
+    // called with AudioFlinger lock held
+    virtual bool invalidateTracks_l(audio_stream_type_t streamType) = 0;
+    virtual bool invalidateTracks_l(std::set<audio_port_handle_t>& portIds) = 0;
+    virtual void invalidateTracks(audio_stream_type_t streamType) = 0;
+    // Invalidate tracks by a set of port ids. The port id will be removed from
+    // the given set if the corresponding track is found and invalidated.
+    virtual void invalidateTracks(std::set<audio_port_handle_t>& portIds) = 0;
+
+    virtual status_t getTimestamp_l(AudioTimestamp& timestamp) = 0;
+    virtual void addPatchTrack(const sp<IAfPatchTrack>& track) = 0;
+    virtual void deletePatchTrack(const sp<IAfPatchTrack>& track) = 0;
+
+    // Return the asynchronous signal wait time.
+    virtual int64_t computeWaitTimeNs_l() const = 0;
+    // returns true if the track is allowed to be added to the thread.
+    virtual bool isTrackAllowed_l(
+            audio_channel_mask_t channelMask, audio_format_t format, audio_session_t sessionId,
+            uid_t uid) const = 0;
+
+    virtual bool supportsHapticPlayback() const = 0;
+
+    virtual void setDownStreamPatch(const struct audio_patch* patch) = 0;
+
+    virtual IAfTrack* getTrackById_l(audio_port_handle_t trackId) = 0;
+
+    virtual bool hasMixer() const = 0;
+
+    virtual status_t setRequestedLatencyMode(audio_latency_mode_t mode) = 0;
+
+    virtual status_t getSupportedLatencyModes(std::vector<audio_latency_mode_t>* modes) = 0;
+
+    virtual status_t setBluetoothVariableLatencyEnabled(bool enabled) = 0;
+
+    virtual void setStandby() = 0;
+    virtual void setStandby_l() = 0;
+    virtual bool waitForHalStart() = 0;
+
+    virtual bool hasFastMixer() const = 0;
+    virtual FastTrackUnderruns getFastTrackUnderruns(size_t fastIndex) const = 0;
+    virtual const std::atomic<int64_t>& framesWritten() const = 0;
+
+    virtual bool usesHwAvSync() const = 0;
+};
+
+class IAfDirectOutputThread : public virtual IAfPlaybackThread {
+public:
+    virtual status_t selectPresentation(int presentationId, int programId) = 0;
+};
+
+class IAfDuplicatingThread : public virtual IAfPlaybackThread {
+public:
+    static sp<IAfDuplicatingThread> create(
+            const sp<AudioFlinger>& audioFlinger, IAfPlaybackThread* mainThread,
+            audio_io_handle_t id, bool systemReady);
+
+    virtual void addOutputTrack(IAfPlaybackThread* thread) = 0;
+    virtual uint32_t waitTimeMs() const = 0;
+    virtual void removeOutputTrack(IAfPlaybackThread* thread) = 0;
+};
+
+class IAfRecordThread : public virtual IAfThreadBase {
+public:
+    static sp<IAfRecordThread> create(
+            const sp<AudioFlinger>& audioFlinger, AudioStreamIn* input, audio_io_handle_t id,
+            bool systemReady);
+
+    virtual sp<IAfRecordTrack> createRecordTrack_l(
+            const sp<Client>& client,
+            const audio_attributes_t& attr,
+            uint32_t* pSampleRate,
+            audio_format_t format,
+            audio_channel_mask_t channelMask,
+            size_t* pFrameCount,
+            audio_session_t sessionId,
+            size_t* pNotificationFrameCount,
+            pid_t creatorPid,
+            const AttributionSourceState& attributionSource,
+            audio_input_flags_t* flags,
+            pid_t tid,
+            status_t* status /*non-NULL*/,
+            audio_port_handle_t portId,
+            int32_t maxSharedAudioHistoryMs) = 0;
+    virtual void destroyTrack_l(const sp<IAfRecordTrack>& track) = 0;
+    virtual void removeTrack_l(const sp<IAfRecordTrack>& track) = 0;
+
+    virtual status_t start(
+            IAfRecordTrack* recordTrack, AudioSystem::sync_event_t event,
+            audio_session_t triggerSession) = 0;
+
+    // ask the thread to stop the specified track, and
+    // return true if the caller should then do it's part of the stopping process
+    virtual bool stop(IAfRecordTrack* recordTrack) = 0;
+
+    virtual AudioStreamIn* getInput() const = 0;
+    virtual AudioStreamIn* clearInput() = 0;
+
+    virtual status_t getActiveMicrophones(
+            std::vector<media::MicrophoneInfoFw>* activeMicrophones) const = 0;
+    virtual status_t setPreferredMicrophoneDirection(audio_microphone_direction_t direction) = 0;
+    virtual status_t setPreferredMicrophoneFieldDimension(float zoom) = 0;
+
+    virtual void addPatchTrack(const sp<IAfPatchRecord>& record) = 0;
+    virtual void deletePatchTrack(const sp<IAfPatchRecord>& record) = 0;
+    virtual bool fastTrackAvailable() const = 0;
+    virtual void setFastTrackAvailable(bool available) = 0;
+
+    virtual void setRecordSilenced(audio_port_handle_t portId, bool silenced) = 0;
+    virtual bool hasFastCapture() const = 0;
+
+    virtual void checkBtNrec() = 0;
+    virtual uint32_t getInputFramesLost() const = 0;
+
+    virtual status_t shareAudioHistory(
+            const std::string& sharedAudioPackageName,
+            audio_session_t sharedSessionId = AUDIO_SESSION_NONE,
+            int64_t sharedAudioStartMs = -1) = 0;
+    virtual void resetAudioHistory_l() = 0;
+};
+
+class IAfMmapThread : public virtual IAfThreadBase {
+public:
+    // createIAudioTrackAdapter() is a static constructor which creates an
+    // MmapStreamInterface AIDL interface adapter from the MmapThread object that
+    // may be passed back to the client.
+    //
+    // Only one AIDL MmapStreamInterface interface adapter should be created per MmapThread.
+    static sp<MmapStreamInterface> createMmapStreamInterfaceAdapter(
+            const sp<IAfMmapThread>& mmapThread);
+
+    virtual void configure(
+            const audio_attributes_t* attr,
+            audio_stream_type_t streamType,
+            audio_session_t sessionId,
+            const sp<MmapStreamCallback>& callback,
+            audio_port_handle_t deviceId,
+            audio_port_handle_t portId) = 0;
+    virtual void disconnect() = 0;
+
+    // MmapStreamInterface handling (see adapter)
+    virtual status_t createMmapBuffer(
+            int32_t minSizeFrames, struct audio_mmap_buffer_info* info) = 0;
+    virtual status_t getMmapPosition(struct audio_mmap_position* position) const = 0;
+    virtual status_t start(
+            const AudioClient& client, const audio_attributes_t* attr,
+            audio_port_handle_t* handle) = 0;
+    virtual status_t stop(audio_port_handle_t handle) = 0;
+    virtual status_t standby() = 0;
+    virtual status_t getExternalPosition(uint64_t* position, int64_t* timeNanos) const = 0;
+    virtual status_t reportData(const void* buffer, size_t frameCount) = 0;
+
+    // TODO(b/291317898)  move to IAfThreadBase?
+    virtual void invalidateTracks(std::set<audio_port_handle_t>& portIds) = 0;
+
+    // Sets the UID records silence - TODO(b/291317898)  move to IAfMmapCaptureThread
+    virtual void setRecordSilenced(audio_port_handle_t portId, bool silenced) = 0;
+
+    virtual sp<IAfMmapPlaybackThread> asIAfMmapPlaybackThread() { return nullptr; }
+    virtual sp<IAfMmapCaptureThread> asIAfMmapCaptureThread() { return nullptr; }
+};
+
+class IAfMmapPlaybackThread : public virtual IAfMmapThread, public virtual VolumeInterface {
+public:
+    static sp<IAfMmapPlaybackThread> create(
+            const sp<AudioFlinger>& audioFlinger, audio_io_handle_t id, AudioHwDevice* hwDev,
+            AudioStreamOut* output, bool systemReady);
+
+    virtual AudioStreamOut* clearOutput() = 0;
+};
+
+class IAfMmapCaptureThread : public virtual IAfMmapThread {
+public:
+    static sp<IAfMmapCaptureThread> create(
+            const sp<AudioFlinger>& audioFlinger, audio_io_handle_t id, AudioHwDevice* hwDev,
+            AudioStreamIn* input, bool systemReady);
+
+    virtual AudioStreamIn* clearInput() = 0;
+};
+
+}  // namespace android
diff --git a/services/audioflinger/IAfTrack.h b/services/audioflinger/IAfTrack.h
index 541be0a..2763157 100644
--- a/services/audioflinger/IAfTrack.h
+++ b/services/audioflinger/IAfTrack.h
@@ -18,6 +18,20 @@
 
 namespace android {
 
+class IAfDuplicatingThread;
+class IAfPatchRecord;
+class IAfPatchTrack;
+class IAfPlaybackThread;
+class IAfRecordThread;
+class IAfThreadBase;
+
+struct TeePatch {
+    sp<IAfPatchRecord> patchRecord;
+    sp<IAfPatchTrack> patchTrack;
+};
+
+using TeePatches = std::vector<TeePatch>;
+
 // Common interface to all Playback and Record tracks.
 class IAfTrackBase : public virtual RefBase {
 public:
@@ -97,8 +111,7 @@
     virtual void releaseBuffer(AudioBufferProvider::Buffer* buffer) = 0;
 
     // Added for RecordTrack and OutputTrack
-    // TODO(b/288339104) type
-    virtual wp<Thread> thread() const = 0;
+    virtual wp<IAfThreadBase> thread() const = 0;
     virtual const sp<ServerProxy>& serverProxy() const = 0;
 
     // TEE_SINK
@@ -208,12 +221,12 @@
 
     /**
      * For RecordTrack
-     * TODO(b/288339104) either use this or add asRecordTrack or asTrack etc.
+     * TODO(b/291317964) either use this or add asRecordTrack or asTrack etc.
      */
     virtual void handleSyncStartEvent(const sp<audioflinger::SyncEvent>& event __unused){};
 
     // For Thread use, fast tracks and offloaded tracks only
-    // TODO(b/288339104) rearrange to IAfTrack.
+    // TODO(b/291317964) rearrange to IAfTrack.
     virtual bool isStopped() const = 0;
     virtual bool isStopping() const = 0;
     virtual bool isStopping_1() const = 0;
@@ -233,8 +246,8 @@
     // Only one AIDL IAudioTrack interface adapter should be created per Track.
     static sp<media::IAudioTrack> createIAudioTrackAdapter(const sp<IAfTrack>& track);
 
-    static sp<IAfTrack> create( // TODO(b/288339104) void*
-            void* /* AudioFlinger::PlaybackThread */ thread,
+    static sp<IAfTrack> create(
+            IAfPlaybackThread* thread,
             const sp<Client>& client,
             audio_stream_type_t streamType,
             const audio_attributes_t& attr,
@@ -321,9 +334,8 @@
     // This function should be called with holding thread lock.
     virtual void updateTeePatches_l() = 0;
 
-    // TODO(b/288339104) type
-    virtual void setTeePatchesToUpdate_l(
-            const void* teePatchesToUpdate /* TeePatches& teePatchesToUpdate */) = 0;
+    // Argument teePatchesToUpdate is by value, use std::move to optimize.
+    virtual void setTeePatchesToUpdate_l(TeePatches teePatchesToUpdate) = 0;
 
     static bool checkServerLatencySupported(audio_format_t format, audio_output_flags_t flags) {
         return audio_is_linear_pcm(format) && (flags & AUDIO_OUTPUT_FLAG_HW_AV_SYNC) == 0;
@@ -388,7 +400,7 @@
     virtual ExtendedAudioBufferProvider* asExtendedAudioBufferProvider() = 0;
     virtual VolumeProvider* asVolumeProvider() = 0;
 
-    // TODO(b/288339104) split into getter/setter
+    // TODO(b/291317964) split into getter/setter
     virtual FillingStatus& fillingStatus() = 0;
     virtual int8_t& retryCount() = 0;
     virtual FastTrackUnderruns& fastTrackUnderruns() = 0;
@@ -397,10 +409,9 @@
 // playback track, used by DuplicatingThread
 class IAfOutputTrack : public virtual IAfTrack {
 public:
-    // TODO(b/288339104) void*
     static sp<IAfOutputTrack> create(
-            void* /* AudioFlinger::PlaybackThread */ playbackThread,
-            void* /* AudioFlinger::DuplicatingThread */ sourceThread, uint32_t sampleRate,
+            IAfPlaybackThread* playbackThread,
+            IAfDuplicatingThread* sourceThread, uint32_t sampleRate,
             audio_format_t format, audio_channel_mask_t channelMask, size_t frameCount,
             const AttributionSourceState& attributionSource);
 
@@ -416,8 +427,7 @@
 
 class IAfMmapTrack : public virtual IAfTrackBase {
 public:
-    // TODO(b/288339104) void*
-    static sp<IAfMmapTrack> create(void* /*AudioFlinger::ThreadBase */ thread,
+    static sp<IAfMmapTrack> create(IAfThreadBase* thread,
             const audio_attributes_t& attr,
             uint32_t sampleRate,
             audio_format_t format,
@@ -454,8 +464,7 @@
     // Only one AIDL IAudioRecord interface adapter should be created per RecordTrack.
     static sp<media::IAudioRecord> createIAudioRecordAdapter(const sp<IAfRecordTrack>& recordTrack);
 
-    // TODO(b/288339104) void*
-    static sp<IAfRecordTrack> create(void* /* AudioFlinger::RecordThread */ thread,
+    static sp<IAfRecordTrack> create(IAfRecordThread* thread,
             const sp<Client>& client,
             const audio_attributes_t& attr,
             uint32_t sampleRate,
@@ -477,7 +486,7 @@
     // set the buffer overflow flag and return previous value
     virtual bool setOverflow() = 0;
 
-    // TODO(b/288339104) handleSyncStartEvent in IAfTrackBase should move here.
+    // TODO(b/291317964) handleSyncStartEvent in IAfTrackBase should move here.
     virtual void clearSyncStartEvent() = 0;
     virtual void updateTrackFrameInfo(
             int64_t trackFramesReleased, int64_t sourceFramesRead, uint32_t halSampleRate,
@@ -533,7 +542,7 @@
 class IAfPatchTrack : public virtual IAfTrack, public virtual IAfPatchTrackBase {
 public:
     static sp<IAfPatchTrack> create(
-            void * /* PlaybackThread */ playbackThread, // TODO(b/288339104)
+            IAfPlaybackThread* playbackThread,
             audio_stream_type_t streamType,
             uint32_t sampleRate,
             audio_channel_mask_t channelMask,
@@ -549,19 +558,10 @@
                                              *  even if it might glitch. */);
 };
 
-// Abstraction for the Audio Source for the RecordThread (HAL or PassthruPatchRecord).
-struct Source {
-    virtual ~Source() = default;
-    // The following methods have the same signatures as in StreamHalInterface.
-    virtual status_t read(void* buffer, size_t bytes, size_t* read) = 0;
-    virtual status_t getCapturePosition(int64_t* frames, int64_t* time) = 0;
-    virtual status_t standby() = 0;
-};
-
 class IAfPatchRecord : public virtual IAfRecordTrack, public virtual IAfPatchTrackBase {
 public:
     static sp<IAfPatchRecord> create(
-            void* /* RecordThread */ recordThread, // TODO(b/288339104)
+            IAfRecordThread* recordThread,
             uint32_t sampleRate,
             audio_channel_mask_t channelMask,
             audio_format_t format,
@@ -573,7 +573,7 @@
             audio_source_t source = AUDIO_SOURCE_DEFAULT);
 
     static sp<IAfPatchRecord> createPassThru(
-            void* /* RecordThread */ recordThread, // TODO(b/288339104)
+            IAfRecordThread* recordThread,
             uint32_t sampleRate,
             audio_channel_mask_t channelMask,
             audio_format_t format,
diff --git a/services/audioflinger/MelReporter.cpp b/services/audioflinger/MelReporter.cpp
index 53d5837..0f739b0 100644
--- a/services/audioflinger/MelReporter.cpp
+++ b/services/audioflinger/MelReporter.cpp
@@ -16,7 +16,7 @@
 */
 
 // #define LOG_NDEBUG 0
-#define LOG_TAG "AudioFlinger::MelReporter"
+#define LOG_TAG "MelReporter"
 
 #include "AudioFlinger.h"
 
@@ -28,7 +28,7 @@
 
 namespace android {
 
-bool AudioFlinger::MelReporter::activateHalSoundDoseComputation(const std::string& module,
+bool MelReporter::activateHalSoundDoseComputation(const std::string& module,
         const sp<DeviceHalInterface>& device) {
     if (mSoundDoseManager->forceUseFrameworkMel()) {
         ALOGD("%s: Forcing use of internal MEL computation.", __func__);
@@ -63,7 +63,7 @@
     return true;
 }
 
-void AudioFlinger::MelReporter::activateInternalSoundDoseComputation() {
+void MelReporter::activateInternalSoundDoseComputation() {
     {
         std::lock_guard _l(mLock);
         if (!mUseHalSoundDoseInterface) {
@@ -76,11 +76,11 @@
     mSoundDoseManager->setHalSoundDoseInterface(nullptr);
 }
 
-void AudioFlinger::MelReporter::onFirstRef() {
+void MelReporter::onFirstRef() {
     mAudioFlinger.mPatchCommandThread->addListener(this);
 }
 
-bool AudioFlinger::MelReporter::shouldComputeMelForDeviceType(audio_devices_t device) {
+bool MelReporter::shouldComputeMelForDeviceType(audio_devices_t device) {
     if (!mSoundDoseManager->isCsdEnabled()) {
         ALOGV("%s csd is disabled", __func__);
         return false;
@@ -104,7 +104,7 @@
     }
 }
 
-void AudioFlinger::MelReporter::updateMetadataForCsd(audio_io_handle_t streamHandle,
+void MelReporter::updateMetadataForCsd(audio_io_handle_t streamHandle,
         const std::vector<playback_track_metadata_v7_t>& metadataVec) {
     if (!mSoundDoseManager->isCsdEnabled()) {
         ALOGV("%s csd is disabled", __func__);
@@ -140,8 +140,8 @@
     }
 }
 
-void AudioFlinger::MelReporter::onCreateAudioPatch(audio_patch_handle_t handle,
-        const PatchPanel::Patch& patch) {
+void MelReporter::onCreateAudioPatch(audio_patch_handle_t handle,
+        const IAfPatchPanel::Patch& patch) {
     if (!mSoundDoseManager->isCsdEnabled()) {
         ALOGV("%s csd is disabled", __func__);
         return;
@@ -180,7 +180,7 @@
     }
 }
 
-void AudioFlinger::MelReporter::startMelComputationForActivePatch_l(const ActiveMelPatch& patch)
+void MelReporter::startMelComputationForActivePatch_l(const ActiveMelPatch& patch)
 NO_THREAD_SAFETY_ANALYSIS  // access of AudioFlinger::checkOutputThread_l
 {
     auto outputThread = mAudioFlinger.checkOutputThread_l(patch.streamHandle);
@@ -198,14 +198,14 @@
             outputThread->startMelComputation_l(mSoundDoseManager->getOrCreateProcessorForDevice(
                 deviceHandle,
                 patch.streamHandle,
-                outputThread->mSampleRate,
-                outputThread->mChannelCount,
-                outputThread->mFormat));
+                outputThread->sampleRate(),
+                outputThread->channelCount(),
+                outputThread->format()));
         }
     }
 }
 
-void AudioFlinger::MelReporter::onReleaseAudioPatch(audio_patch_handle_t handle) {
+void MelReporter::onReleaseAudioPatch(audio_patch_handle_t handle) {
     if (!mSoundDoseManager->isCsdEnabled()) {
         ALOGV("%s csd is disabled", __func__);
         return;
@@ -231,26 +231,26 @@
     stopMelComputationForPatch_l(melPatch);
 }
 
-void AudioFlinger::MelReporter::onUpdateAudioPatch(audio_patch_handle_t oldHandle,
-        audio_patch_handle_t newHandle, const PatchPanel::Patch& patch) {
+void MelReporter::onUpdateAudioPatch(audio_patch_handle_t oldHandle,
+        audio_patch_handle_t newHandle, const IAfPatchPanel::Patch& patch) {
     onReleaseAudioPatch(oldHandle);
     onCreateAudioPatch(newHandle, patch);
 }
 
-sp<media::ISoundDose> AudioFlinger::MelReporter::getSoundDoseInterface(
+sp<media::ISoundDose> MelReporter::getSoundDoseInterface(
         const sp<media::ISoundDoseCallback>& callback) {
     // no need to lock since getSoundDoseInterface is synchronized
     return mSoundDoseManager->getSoundDoseInterface(callback);
 }
 
-void AudioFlinger::MelReporter::stopInternalMelComputation() {
+void MelReporter::stopInternalMelComputation() {
     ALOGV("%s", __func__);
     std::lock_guard _l(mLock);
     mActiveMelPatches.clear();
     mUseHalSoundDoseInterface = true;
 }
 
-void AudioFlinger::MelReporter::stopMelComputationForPatch_l(const ActiveMelPatch& patch)
+void MelReporter::stopMelComputationForPatch_l(const ActiveMelPatch& patch)
 NO_THREAD_SAFETY_ANALYSIS  // access of AudioFlinger::checkOutputThread_l
 {
     if (!patch.csdActive) {
@@ -278,7 +278,7 @@
 }
 
 
-std::optional<audio_patch_handle_t> AudioFlinger::MelReporter::activePatchStreamHandle_l(
+std::optional<audio_patch_handle_t> MelReporter::activePatchStreamHandle_l(
         audio_io_handle_t streamHandle) {
     for(const auto& patchIt : mActiveMelPatches) {
         if (patchIt.second.streamHandle == streamHandle) {
@@ -288,11 +288,11 @@
     return std::nullopt;
 }
 
-bool AudioFlinger::MelReporter::useHalSoundDoseInterface_l() {
+bool MelReporter::useHalSoundDoseInterface_l() {
     return !mSoundDoseManager->forceUseFrameworkMel() & mUseHalSoundDoseInterface;
 }
 
-std::string AudioFlinger::MelReporter::dump() {
+std::string MelReporter::dump() {
     std::lock_guard _l(mLock);
     std::string output("\nSound Dose:\n");
     output.append(mSoundDoseManager->dump());
diff --git a/services/audioflinger/MelReporter.h b/services/audioflinger/MelReporter.h
index 08bbd13..f191c9c 100644
--- a/services/audioflinger/MelReporter.h
+++ b/services/audioflinger/MelReporter.h
@@ -15,14 +15,14 @@
 ** limitations under the License.
 */
 
-#ifndef INCLUDING_FROM_AUDIOFLINGER_H
-    #error This header file should only be included from AudioFlinger.h
-#endif
+#pragma once
 
 #include <mutex>
 #include <sounddose/SoundDoseManager.h>
 #include <unordered_map>
 
+namespace android {
+
 constexpr static int kMaxTimestampDeltaInSec = 120;
 
 /**
@@ -67,11 +67,11 @@
 
     // PatchCommandListener methods
     void onCreateAudioPatch(audio_patch_handle_t handle,
-                            const PatchPanel::Patch& patch) override;
-    void onReleaseAudioPatch(audio_patch_handle_t handle) override;
+        const IAfPatchPanel::Patch& patch) final;
+    void onReleaseAudioPatch(audio_patch_handle_t handle) final;
     void onUpdateAudioPatch(audio_patch_handle_t oldHandle,
                             audio_patch_handle_t newHandle,
-                            const PatchPanel::Patch& patch) override;
+                            const IAfPatchPanel::Patch& patch) final;
 
     /**
      * The new metadata can determine whether we should compute MEL for the given thread.
@@ -112,9 +112,9 @@
      * Locking order AudioFlinger::mLock -> PatchCommandThread::mLock -> MelReporter::mLock.
      */
     std::mutex mLock;
-    std::unordered_map<audio_patch_handle_t, ActiveMelPatch>
-        mActiveMelPatches GUARDED_BY(AudioFlinger::MelReporter::mLock);
-    std::unordered_map<audio_port_handle_t, int>
-        mActiveDevices GUARDED_BY(AudioFlinger::MelReporter::mLock);
-    bool mUseHalSoundDoseInterface GUARDED_BY(AudioFlinger::MelReporter::mLock) = false;
+    std::unordered_map<audio_patch_handle_t, ActiveMelPatch> mActiveMelPatches GUARDED_BY(mLock);
+    std::unordered_map<audio_port_handle_t, int> mActiveDevices GUARDED_BY(mLock);
+    bool mUseHalSoundDoseInterface GUARDED_BY(mLock) = false;
 };
+
+}  // namespace android
diff --git a/services/audioflinger/MmapTracks.h b/services/audioflinger/MmapTracks.h
index 081af74..c695098 100644
--- a/services/audioflinger/MmapTracks.h
+++ b/services/audioflinger/MmapTracks.h
@@ -22,7 +22,7 @@
 // playback track
 class MmapTrack : public TrackBase, public IAfMmapTrack {
 public:
-                MmapTrack(AudioFlinger::ThreadBase* thread,
+    MmapTrack(IAfThreadBase* thread,
                             const audio_attributes_t& attr,
                             uint32_t sampleRate,
                             audio_format_t format,
@@ -60,10 +60,8 @@
      */
     void processMuteEvent_l(const sp<IAudioManager>& audioManager,
                             mute_state_t muteState)
-                            REQUIRES(AudioFlinger::MmapPlaybackThread::mLock) final;
+                            /* REQUIRES(MmapPlaybackThread::mLock) */ final;
 private:
-    friend class MmapThread;
-
     DISALLOW_COPY_AND_ASSIGN(MmapTrack);
 
     // AudioBufferProvider interface
@@ -82,9 +80,9 @@
     // TODO: replace PersistableBundle with own struct
     // access these two variables only when holding player thread lock.
     std::unique_ptr<os::PersistableBundle> mMuteEventExtras
-            GUARDED_BY(AudioFlinger::MmapPlaybackThread::mLock);
+            /* GUARDED_BY(MmapPlaybackThread::mLock) */;
     mute_state_t mMuteState
-            GUARDED_BY(AudioFlinger::MmapPlaybackThread::mLock);
+            /* GUARDED_BY(MmapPlaybackThread::mLock) */;
 };  // end of Track
 
 } // namespace android
\ No newline at end of file
diff --git a/services/audioflinger/PatchCommandThread.cpp b/services/audioflinger/PatchCommandThread.cpp
index 858784d..2849da4 100644
--- a/services/audioflinger/PatchCommandThread.cpp
+++ b/services/audioflinger/PatchCommandThread.cpp
@@ -24,25 +24,25 @@
 
 constexpr char kPatchCommandThreadName[] = "AudioFlinger_PatchCommandThread";
 
-AudioFlinger::PatchCommandThread::~PatchCommandThread() {
+PatchCommandThread::~PatchCommandThread() {
     exit();
 
     std::lock_guard _l(mLock);
     mCommands.clear();
 }
 
-void AudioFlinger::PatchCommandThread::onFirstRef() {
+void PatchCommandThread::onFirstRef() {
     run(kPatchCommandThreadName, ANDROID_PRIORITY_AUDIO);
 }
 
-void AudioFlinger::PatchCommandThread::addListener(const sp<PatchCommandListener>& listener) {
+void PatchCommandThread::addListener(const sp<PatchCommandListener>& listener) {
     ALOGV("%s add listener %p", __func__, static_cast<void*>(listener.get()));
     std::lock_guard _l(mListenerLock);
     mListeners.emplace_back(listener);
 }
 
-void AudioFlinger::PatchCommandThread::createAudioPatch(audio_patch_handle_t handle,
-        const PatchPanel::Patch& patch) {
+void PatchCommandThread::createAudioPatch(audio_patch_handle_t handle,
+        const IAfPatchPanel::Patch& patch) {
     ALOGV("%s handle %d mHalHandle %d num sinks %d device sink %08x",
             __func__, handle, patch.mHalHandle,
             patch.mAudioPatch.num_sinks,
@@ -51,13 +51,13 @@
     createAudioPatchCommand(handle, patch);
 }
 
-void AudioFlinger::PatchCommandThread::releaseAudioPatch(audio_patch_handle_t handle) {
+void PatchCommandThread::releaseAudioPatch(audio_patch_handle_t handle) {
     ALOGV("%s", __func__);
     releaseAudioPatchCommand(handle);
 }
 
-void AudioFlinger::PatchCommandThread::updateAudioPatch(audio_patch_handle_t oldHandle,
-        audio_patch_handle_t newHandle, const PatchPanel::Patch& patch) {
+void PatchCommandThread::updateAudioPatch(audio_patch_handle_t oldHandle,
+        audio_patch_handle_t newHandle, const IAfPatchPanel::Patch& patch) {
     ALOGV("%s handle %d mHalHandle %d num sinks %d device sink %08x",
             __func__, oldHandle, patch.mHalHandle,
             patch.mAudioPatch.num_sinks,
@@ -66,7 +66,7 @@
     updateAudioPatchCommand(oldHandle, newHandle, patch);
 }
 
-bool AudioFlinger::PatchCommandThread::threadLoop()
+bool PatchCommandThread::threadLoop()
 NO_THREAD_SAFETY_ANALYSIS  // bug in clang compiler.
 {
     std::unique_lock _l(mLock);
@@ -144,14 +144,14 @@
     return false;
 }
 
-void AudioFlinger::PatchCommandThread::sendCommand(const sp<Command>& command) {
+void PatchCommandThread::sendCommand(const sp<Command>& command) {
     std::lock_guard _l(mLock);
     mCommands.emplace_back(command);
     mWaitWorkCV.notify_one();
 }
 
-void AudioFlinger::PatchCommandThread::createAudioPatchCommand(
-        audio_patch_handle_t handle, const PatchPanel::Patch& patch) {
+void PatchCommandThread::createAudioPatchCommand(
+        audio_patch_handle_t handle, const IAfPatchPanel::Patch& patch) {
     auto command = sp<Command>::make(CREATE_AUDIO_PATCH,
                                      new CreateAudioPatchData(handle, patch));
     ALOGV("%s adding create patch handle %d mHalHandle %d.",
@@ -161,16 +161,16 @@
     sendCommand(command);
 }
 
-void AudioFlinger::PatchCommandThread::releaseAudioPatchCommand(audio_patch_handle_t handle) {
+void PatchCommandThread::releaseAudioPatchCommand(audio_patch_handle_t handle) {
     sp<Command> command =
         sp<Command>::make(RELEASE_AUDIO_PATCH, new ReleaseAudioPatchData(handle));
     ALOGV("%s adding release patch", __func__);
     sendCommand(command);
 }
 
-void AudioFlinger::PatchCommandThread::updateAudioPatchCommand(
+void PatchCommandThread::updateAudioPatchCommand(
         audio_patch_handle_t oldHandle, audio_patch_handle_t newHandle,
-        const PatchPanel::Patch& patch) {
+        const IAfPatchPanel::Patch& patch) {
     sp<Command> command = sp<Command>::make(UPDATE_AUDIO_PATCH,
                                            new UpdateAudioPatchData(oldHandle, newHandle, patch));
     ALOGV("%s adding update patch old handle %d new handle %d mHalHandle %d.",
@@ -178,7 +178,7 @@
     sendCommand(command);
 }
 
-void AudioFlinger::PatchCommandThread::exit() {
+void PatchCommandThread::exit() {
     ALOGV("%s", __func__);
     {
         std::lock_guard _l(mLock);
diff --git a/services/audioflinger/PatchCommandThread.h b/services/audioflinger/PatchCommandThread.h
index ea87c0f..6cf0505 100644
--- a/services/audioflinger/PatchCommandThread.h
+++ b/services/audioflinger/PatchCommandThread.h
@@ -15,14 +15,14 @@
 ** limitations under the License.
 */
 
-#ifndef INCLUDING_FROM_AUDIOFLINGER_H
-    #error This header file should only be included from AudioFlinger.h
-#endif
+#pragma once
+
+namespace android {
 
 class Command;
 
 // Thread to execute create and release patch commands asynchronously. This is needed because
-// PatchPanel::createAudioPatch and releaseAudioPatch are executed from audio policy service
+// IAfPatchPanel::createAudioPatch and releaseAudioPatch are executed from audio policy service
 // with mutex locked and effect management requires to call back into audio policy service
 class PatchCommandThread : public Thread {
 public:
@@ -36,11 +36,11 @@
     class PatchCommandListener : public virtual RefBase {
     public:
         virtual void onCreateAudioPatch(audio_patch_handle_t handle,
-                                        const PatchPanel::Patch& patch) = 0;
+                                        const IAfPatchPanel::Patch& patch) = 0;
         virtual void onReleaseAudioPatch(audio_patch_handle_t handle) = 0;
         virtual void onUpdateAudioPatch(audio_patch_handle_t oldHandle,
                                         audio_patch_handle_t newHandle,
-                                        const PatchPanel::Patch& patch) = 0;
+                                        const IAfPatchPanel::Patch& patch) = 0;
     };
 
     PatchCommandThread() : Thread(false /* canCallJava */) {}
@@ -48,11 +48,11 @@
 
     void addListener(const sp<PatchCommandListener>& listener);
 
-    void createAudioPatch(audio_patch_handle_t handle, const PatchPanel::Patch& patch);
+    void createAudioPatch(audio_patch_handle_t handle, const IAfPatchPanel::Patch& patch);
     void releaseAudioPatch(audio_patch_handle_t handle);
     void updateAudioPatch(audio_patch_handle_t oldHandle,
                           audio_patch_handle_t newHandle,
-                          const PatchPanel::Patch& patch);
+                          const IAfPatchPanel::Patch& patch);
 
     // Thread virtuals
     void onFirstRef() override;
@@ -61,11 +61,11 @@
     void exit();
 
     void createAudioPatchCommand(audio_patch_handle_t handle,
-            const PatchPanel::Patch& patch);
+            const IAfPatchPanel::Patch& patch);
     void releaseAudioPatchCommand(audio_patch_handle_t handle);
     void updateAudioPatchCommand(audio_patch_handle_t oldHandle,
                                  audio_patch_handle_t newHandle,
-                                 const PatchPanel::Patch& patch);
+                                 const IAfPatchPanel::Patch& patch);
 private:
     class CommandData;
 
@@ -84,11 +84,11 @@
 
     class CreateAudioPatchData : public CommandData {
     public:
-        CreateAudioPatchData(audio_patch_handle_t handle, const PatchPanel::Patch& patch)
+        CreateAudioPatchData(audio_patch_handle_t handle, const IAfPatchPanel::Patch& patch)
             :   mHandle(handle), mPatch(patch) {}
 
         const audio_patch_handle_t mHandle;
-        const PatchPanel::Patch mPatch;
+        const IAfPatchPanel::Patch mPatch;
     };
 
     class ReleaseAudioPatchData : public CommandData {
@@ -103,12 +103,12 @@
     public:
         UpdateAudioPatchData(audio_patch_handle_t oldHandle,
                              audio_patch_handle_t newHandle,
-                             const PatchPanel::Patch& patch)
+                             const IAfPatchPanel::Patch& patch)
             :   mOldHandle(oldHandle), mNewHandle(newHandle), mPatch(patch) {}
 
         const audio_patch_handle_t mOldHandle;
         const audio_patch_handle_t mNewHandle;
-        const PatchPanel::Patch mPatch;
+        const IAfPatchPanel::Patch mPatch;
     };
 
     void sendCommand(const sp<Command>& command);
@@ -121,3 +121,5 @@
     std::mutex mListenerLock;
     std::vector<wp<PatchCommandListener>> mListeners GUARDED_BY(mListenerLock);
 };
+
+}  // namespace android
diff --git a/services/audioflinger/PatchPanel.cpp b/services/audioflinger/PatchPanel.cpp
index 6deb093..bede225 100644
--- a/services/audioflinger/PatchPanel.cpp
+++ b/services/audioflinger/PatchPanel.cpp
@@ -24,6 +24,7 @@
 #include <audio_utils/primitives.h>
 
 #include "AudioFlinger.h"
+#include "PatchPanel.h"
 #include <media/AudioParameter.h>
 #include <media/AudioValidator.h>
 #include <media/DeviceDescriptorBase.h>
@@ -52,7 +53,7 @@
                                 struct audio_port *ports)
 {
     Mutex::Autolock _l(mLock);
-    return mPatchPanel.listAudioPorts(num_ports, ports);
+    return mPatchPanel->listAudioPorts(num_ports, ports);
 }
 
 /* Get supported attributes for a given audio port */
@@ -63,7 +64,7 @@
     }
 
     Mutex::Autolock _l(mLock);
-    return mPatchPanel.getAudioPort(port);
+    return mPatchPanel->getAudioPort(port);
 }
 
 /* Connect a patch between several source and sink ports */
@@ -76,14 +77,14 @@
     }
 
     Mutex::Autolock _l(mLock);
-    return mPatchPanel.createAudioPatch(patch, handle);
+    return mPatchPanel->createAudioPatch(patch, handle);
 }
 
 /* Disconnect a patch */
 status_t AudioFlinger::releaseAudioPatch(audio_patch_handle_t handle)
 {
     Mutex::Autolock _l(mLock);
-    return mPatchPanel.releaseAudioPatch(handle);
+    return mPatchPanel->releaseAudioPatch(handle);
 }
 
 /* List connected audio ports and they attributes */
@@ -91,21 +92,46 @@
                                   struct audio_patch *patches)
 {
     Mutex::Autolock _l(mLock);
-    return mPatchPanel.listAudioPatches(num_patches, patches);
+    return mPatchPanel->listAudioPatches(num_patches, patches);
 }
 
-status_t AudioFlinger::PatchPanel::SoftwarePatch::getLatencyMs_l(double *latencyMs) const
+/* static */
+sp<IAfPatchPanel> IAfPatchPanel::create(AudioFlinger* audioFlinger) {
+    return sp<PatchPanel>::make(audioFlinger);
+}
+
+status_t SoftwarePatch::getLatencyMs_l(double* latencyMs) const {
+    return mPatchPanel->getLatencyMs_l(mPatchHandle, latencyMs);
+}
+
+status_t PatchPanel::getLatencyMs_l(
+        audio_patch_handle_t patchHandle, double* latencyMs) const
 {
-    const auto& iter = mPatchPanel.mPatches.find(mPatchHandle);
-    if (iter != mPatchPanel.mPatches.end()) {
+    const auto& iter = mPatches.find(patchHandle);
+    if (iter != mPatches.end()) {
         return iter->second.getLatencyMs(latencyMs);
     } else {
         return BAD_VALUE;
     }
 }
 
+void PatchPanel::closeThreadInternal_l(const sp<IAfThreadBase>& thread) const
+{
+    if (const auto recordThread = thread->asIAfRecordThread();
+            recordThread) {
+        mAudioFlinger.closeThreadInternal_l(recordThread);
+    } else if (const auto playbackThread = thread->asIAfPlaybackThread();
+            playbackThread) {
+        mAudioFlinger.closeThreadInternal_l(playbackThread);
+    } else {
+        LOG_ALWAYS_FATAL("%s: Endpoints only accept IAfPlayback and IAfRecord threads, "
+                "invalid thread, id: %d  type: %d",
+                __func__, thread->id(), thread->type());
+    }
+}
+
 /* List connected audio ports and their attributes */
-status_t AudioFlinger::PatchPanel::listAudioPorts(unsigned int *num_ports __unused,
+status_t PatchPanel::listAudioPorts(unsigned int* /* num_ports */,
                                 struct audio_port *ports __unused)
 {
     ALOGV(__func__);
@@ -113,7 +139,7 @@
 }
 
 /* Get supported attributes for a given audio port */
-status_t AudioFlinger::PatchPanel::getAudioPort(struct audio_port_v7 *port)
+status_t PatchPanel::getAudioPort(struct audio_port_v7* port)
 {
     if (port->type != AUDIO_PORT_TYPE_DEVICE) {
         // Only query the HAL when the port is a device.
@@ -132,10 +158,10 @@
 }
 
 /* Connect a patch between several source and sink ports */
-status_t AudioFlinger::PatchPanel::createAudioPatch(const struct audio_patch *patch,
+status_t PatchPanel::createAudioPatch(const struct audio_patch* patch,
                                    audio_patch_handle_t *handle,
                                    bool endpointPatch)
- //unlocks AudioFlinger::mLock when calling ThreadBase::sendCreateAudioPatchConfigEvent
+ //unlocks AudioFlinger::mLock when calling IAfThreadBase::sendCreateAudioPatchConfigEvent
  //to avoid deadlocks if the thread loop needs to acquire AudioFlinger::mLock
  //before processing the create patch request.
  NO_THREAD_SAFETY_ANALYSIS
@@ -255,7 +281,7 @@
                         status = INVALID_OPERATION;
                         goto exit;
                     }
-                    sp<ThreadBase> thread =
+                    const sp<IAfThreadBase> thread =
                             mAudioFlinger.checkPlaybackThread_l(patch->sources[1].ext.mix.handle);
                     if (thread == 0) {
                         ALOGW("%s() cannot get playback thread", __func__);
@@ -264,7 +290,7 @@
                     }
                     // existing playback thread is reused, so it is not closed when patch is cleared
                     newPatch.mPlayback.setThread(
-                            reinterpret_cast<PlaybackThread*>(thread.get()), false /*closeThread*/);
+                            thread->asIAfPlaybackThread().get(), false /*closeThread*/);
                 } else {
                     audio_config_t config = AUDIO_CONFIG_INITIALIZER;
                     audio_config_base_t mixerConfig = AUDIO_CONFIG_BASE_INITIALIZER;
@@ -282,7 +308,7 @@
                     if (patch->sinks[0].config_mask & AUDIO_PORT_CONFIG_FLAGS) {
                         flags = patch->sinks[0].flags.output;
                     }
-                    sp<ThreadBase> thread = mAudioFlinger.openOutput_l(
+                    const sp<IAfThreadBase> thread = mAudioFlinger.openOutput_l(
                                                             patch->sinks[0].ext.device.hw_module,
                                                             &output,
                                                             &config,
@@ -295,7 +321,7 @@
                         status = NO_MEMORY;
                         goto exit;
                     }
-                    newPatch.mPlayback.setThread(reinterpret_cast<PlaybackThread*>(thread.get()));
+                    newPatch.mPlayback.setThread(thread->asIAfPlaybackThread().get());
                 }
                 audio_devices_t device = patch->sources[0].ext.device.type;
                 String8 address = String8(patch->sources[0].ext.device.address);
@@ -329,7 +355,7 @@
                                 == AUDIO_STREAM_VOICE_CALL) {
                     source = AUDIO_SOURCE_VOICE_COMMUNICATION;
                 }
-                sp<ThreadBase> thread = mAudioFlinger.openInput_l(srcModule,
+                const sp<IAfThreadBase> thread = mAudioFlinger.openInput_l(srcModule,
                                                                     &input,
                                                                     &config,
                                                                     device,
@@ -344,7 +370,7 @@
                     status = NO_MEMORY;
                     goto exit;
                 }
-                newPatch.mRecord.setThread(reinterpret_cast<RecordThread*>(thread.get()));
+                newPatch.mRecord.setThread(thread->asIAfRecordThread().get());
                 status = newPatch.createConnections(this);
                 if (status != NO_ERROR) {
                     goto exit;
@@ -354,7 +380,7 @@
                 }
             } else {
                 if (patch->sinks[0].type == AUDIO_PORT_TYPE_MIX) {
-                    sp<ThreadBase> thread = mAudioFlinger.checkRecordThread_l(
+                    sp<IAfThreadBase> thread = mAudioFlinger.checkRecordThread_l(
                                                               patch->sinks[0].ext.mix.handle);
                     if (thread == 0) {
                         thread = mAudioFlinger.checkMmapThread_l(patch->sinks[0].ext.mix.handle);
@@ -417,7 +443,7 @@
                 device->applyAudioPortConfig(&patch->sinks[i]);
                 devices.push_back(device);
             }
-            sp<ThreadBase> thread =
+            sp<IAfThreadBase> thread =
                             mAudioFlinger.checkPlaybackThread_l(patch->sources[0].ext.mix.handle);
             if (thread == 0) {
                 thread = mAudioFlinger.checkMmapThread_l(patch->sources[0].ext.mix.handle);
@@ -476,13 +502,13 @@
     return status;
 }
 
-AudioFlinger::PatchPanel::Patch::~Patch()
+PatchPanel::Patch::~Patch()
 {
     ALOGE_IF(isSoftware(), "Software patch connections leaked %d %d",
             mRecord.handle(), mPlayback.handle());
 }
 
-status_t AudioFlinger::PatchPanel::Patch::createConnections(PatchPanel *panel)
+status_t PatchPanel::Patch::createConnections(const sp<IAfPatchPanel>& panel)
 {
     // create patch from source device to record thread input
     status_t status = panel->createAudioPatch(
@@ -646,7 +672,7 @@
     return status;
 }
 
-void AudioFlinger::PatchPanel::Patch::clearConnections(PatchPanel *panel)
+void PatchPanel::Patch::clearConnections(const sp<IAfPatchPanel>& panel)
 {
     ALOGV("%s() mRecord.handle %d mPlayback.handle %d",
             __func__, mRecord.handle(), mPlayback.handle());
@@ -657,7 +683,7 @@
     mPlayback.closeConnections(panel);
 }
 
-status_t AudioFlinger::PatchPanel::Patch::getLatencyMs(double *latencyMs) const
+status_t PatchPanel::Patch::getLatencyMs(double* latencyMs) const
 {
     if (!isSoftware()) return INVALID_OPERATION;
 
@@ -716,7 +742,7 @@
     return INVALID_OPERATION;
 }
 
-String8 AudioFlinger::PatchPanel::Patch::dump(audio_patch_handle_t myHandle) const
+String8 PatchPanel::Patch::dump(audio_patch_handle_t myHandle) const
 {
     // TODO: Consider table dump form for patches, just like tracks.
     String8 result = String8::format("Patch %d: %s (thread %p => thread %p)",
@@ -744,8 +770,8 @@
 }
 
 /* Disconnect a patch */
-status_t AudioFlinger::PatchPanel::releaseAudioPatch(audio_patch_handle_t handle)
- //unlocks AudioFlinger::mLock when calling ThreadBase::sendReleaseAudioPatchConfigEvent
+status_t PatchPanel::releaseAudioPatch(audio_patch_handle_t handle)
+ //unlocks AudioFlinger::mLock when calling IAfThreadBase::sendReleaseAudioPatchConfigEvent
  //to avoid deadlocks if the thread loop needs to acquire AudioFlinger::mLock
  //before processing the release patch request.
  NO_THREAD_SAFETY_ANALYSIS
@@ -777,7 +803,7 @@
 
             if (patch.sinks[0].type == AUDIO_PORT_TYPE_MIX) {
                 audio_io_handle_t ioHandle = patch.sinks[0].ext.mix.handle;
-                sp<ThreadBase> thread = mAudioFlinger.checkRecordThread_l(ioHandle);
+                sp<IAfThreadBase> thread = mAudioFlinger.checkRecordThread_l(ioHandle);
                 if (thread == 0) {
                     thread = mAudioFlinger.checkMmapThread_l(ioHandle);
                     if (thread == 0) {
@@ -800,7 +826,7 @@
                 break;
             }
             audio_io_handle_t ioHandle = src.ext.mix.handle;
-            sp<ThreadBase> thread = mAudioFlinger.checkPlaybackThread_l(ioHandle);
+            sp<IAfThreadBase> thread = mAudioFlinger.checkPlaybackThread_l(ioHandle);
             if (thread == 0) {
                 thread = mAudioFlinger.checkMmapThread_l(ioHandle);
                 if (thread == 0) {
@@ -821,7 +847,7 @@
     return status;
 }
 
-void AudioFlinger::PatchPanel::erasePatch(audio_patch_handle_t handle, bool reuseExistingHalPatch) {
+void PatchPanel::erasePatch(audio_patch_handle_t handle, bool reuseExistingHalPatch) {
     mPatches.erase(handle);
     removeSoftwarePatchFromInsertedModules(handle);
     if (!reuseExistingHalPatch) {
@@ -830,16 +856,16 @@
 }
 
 /* List connected audio ports and they attributes */
-status_t AudioFlinger::PatchPanel::listAudioPatches(unsigned int *num_patches __unused,
+status_t PatchPanel::listAudioPatches(unsigned int* /* num_patches */,
                                   struct audio_patch *patches __unused)
 {
     ALOGV(__func__);
     return NO_ERROR;
 }
 
-status_t AudioFlinger::PatchPanel::getDownstreamSoftwarePatches(
+status_t PatchPanel::getDownstreamSoftwarePatches(
         audio_io_handle_t stream,
-        std::vector<AudioFlinger::PatchPanel::SoftwarePatch> *patches) const
+        std::vector<SoftwarePatch>* patches) const
 {
     for (const auto& module : mInsertedModules) {
         if (module.second.streams.count(stream)) {
@@ -847,7 +873,8 @@
                 const auto& patch_iter = mPatches.find(patchHandle);
                 if (patch_iter != mPatches.end()) {
                     const Patch &patch = patch_iter->second;
-                    patches->emplace_back(*this, patchHandle,
+                    patches->emplace_back(sp<const IAfPatchPanel>::fromExisting(this),
+                            patchHandle,
                             patch.mPlayback.const_thread()->id(),
                             patch.mRecord.const_thread()->id());
                 } else {
@@ -861,7 +888,7 @@
     return BAD_VALUE;
 }
 
-void AudioFlinger::PatchPanel::notifyStreamOpened(
+void PatchPanel::notifyStreamOpened(
         AudioHwDevice *audioHwDevice, audio_io_handle_t stream, struct audio_patch *patch)
 {
     if (audioHwDevice->isInsert()) {
@@ -879,14 +906,14 @@
     }
 }
 
-void AudioFlinger::PatchPanel::notifyStreamClosed(audio_io_handle_t stream)
+void PatchPanel::notifyStreamClosed(audio_io_handle_t stream)
 {
     for (auto& module : mInsertedModules) {
         module.second.streams.erase(stream);
     }
 }
 
-AudioHwDevice* AudioFlinger::PatchPanel::findAudioHwDeviceByModule(audio_module_handle_t module)
+AudioHwDevice* PatchPanel::findAudioHwDeviceByModule(audio_module_handle_t module)
 {
     if (module == AUDIO_MODULE_HANDLE_NONE) return nullptr;
     ssize_t index = mAudioFlinger.mAudioHwDevs.indexOfKey(module);
@@ -897,13 +924,13 @@
     return mAudioFlinger.mAudioHwDevs.valueAt(index);
 }
 
-sp<DeviceHalInterface> AudioFlinger::PatchPanel::findHwDeviceByModule(audio_module_handle_t module)
+sp<DeviceHalInterface> PatchPanel::findHwDeviceByModule(audio_module_handle_t module)
 {
     AudioHwDevice *audioHwDevice = findAudioHwDeviceByModule(module);
     return audioHwDevice ? audioHwDevice->hwDevice() : nullptr;
 }
 
-void AudioFlinger::PatchPanel::addSoftwarePatchToInsertedModules(
+void PatchPanel::addSoftwarePatchToInsertedModules(
         audio_module_handle_t module, audio_patch_handle_t handle,
         const struct audio_patch *patch)
 {
@@ -913,7 +940,7 @@
     }
 }
 
-void AudioFlinger::PatchPanel::removeSoftwarePatchFromInsertedModules(
+void PatchPanel::removeSoftwarePatchFromInsertedModules(
         audio_patch_handle_t handle)
 {
     for (auto& module : mInsertedModules) {
@@ -921,7 +948,7 @@
     }
 }
 
-void AudioFlinger::PatchPanel::dump(int fd) const
+void PatchPanel::dump(int fd) const
 {
     String8 patchPanelDump;
     const char *indent = "  ";
diff --git a/services/audioflinger/PatchPanel.h b/services/audioflinger/PatchPanel.h
index 63c5630..6ef4d1a 100644
--- a/services/audioflinger/PatchPanel.h
+++ b/services/audioflinger/PatchPanel.h
@@ -15,217 +15,52 @@
 ** limitations under the License.
 */
 
-#ifndef INCLUDING_FROM_AUDIOFLINGER_H
-    #error This header file should only be included from AudioFlinger.h
-#endif
+#pragma once
 
-public: // TODO(b/288339104) extract out of AudioFlinger class
-// PatchPanel is concealed within AudioFlinger, their lifetimes are the same.
-class PatchPanel {
+namespace android {
+
+class PatchPanel : public IAfPatchPanel {
 public:
-    class SoftwarePatch {
-      public:
-        SoftwarePatch(const PatchPanel &patchPanel, audio_patch_handle_t patchHandle,
-                audio_io_handle_t playbackThreadHandle, audio_io_handle_t recordThreadHandle)
-                : mPatchPanel(patchPanel), mPatchHandle(patchHandle),
-                  mPlaybackThreadHandle(playbackThreadHandle),
-                  mRecordThreadHandle(recordThreadHandle) {}
-        SoftwarePatch(const SoftwarePatch&) = default;
-
-        // Must be called under AudioFlinger::mLock
-        status_t getLatencyMs_l(double *latencyMs) const;
-        audio_patch_handle_t getPatchHandle() const { return mPatchHandle; };
-        audio_io_handle_t getPlaybackThreadHandle() const { return mPlaybackThreadHandle; };
-        audio_io_handle_t getRecordThreadHandle() const { return mRecordThreadHandle; };
-      private:
-        const PatchPanel &mPatchPanel;
-        const audio_patch_handle_t mPatchHandle;
-        const audio_io_handle_t mPlaybackThreadHandle;
-        const audio_io_handle_t mRecordThreadHandle;
-    };
-
     explicit PatchPanel(AudioFlinger* audioFlinger) : mAudioFlinger(*audioFlinger) {}
 
     /* List connected audio ports and their attributes */
     status_t listAudioPorts(unsigned int *num_ports,
-                                    struct audio_port *ports);
+        struct audio_port* ports) final;
 
     /* Get supported attributes for a given audio port */
-    status_t getAudioPort(struct audio_port_v7 *port);
+    status_t getAudioPort(struct audio_port_v7* port) final;
 
     /* Create a patch between several source and sink ports */
     status_t createAudioPatch(const struct audio_patch *patch,
                               audio_patch_handle_t *handle,
-                              bool endpointPatch = false);
+                              bool endpointPatch = false) final;
 
     /* Release a patch */
-    status_t releaseAudioPatch(audio_patch_handle_t handle);
+    status_t releaseAudioPatch(audio_patch_handle_t handle) final;
 
     /* List connected audio devices and they attributes */
     status_t listAudioPatches(unsigned int *num_patches,
-                                      struct audio_patch *patches);
+            struct audio_patch* patches) final;
 
     // Retrieves all currently estrablished software patches for a stream
     // opened on an intermediate module.
     status_t getDownstreamSoftwarePatches(audio_io_handle_t stream,
-            std::vector<SoftwarePatch> *patches) const;
+            std::vector<SoftwarePatch>* patches) const final;
 
     // Notifies patch panel about all opened and closed streams.
     void notifyStreamOpened(AudioHwDevice *audioHwDevice, audio_io_handle_t stream,
-                            struct audio_patch *patch);
-    void notifyStreamClosed(audio_io_handle_t stream);
+                            struct audio_patch* patch) final;
+    void notifyStreamClosed(audio_io_handle_t stream) final;
 
-    void dump(int fd) const;
-
-    template<typename ThreadType, typename TrackType>
-    class Endpoint final {
-    public:
-        Endpoint() = default;
-        Endpoint(const Endpoint&) = delete;
-        Endpoint& operator=(const Endpoint& other) noexcept {
-            mThread = other.mThread;
-            mCloseThread = other.mCloseThread;
-            mHandle = other.mHandle;
-            mTrack = other.mTrack;
-            return *this;
-        }
-        Endpoint(Endpoint&& other) noexcept { swap(other); }
-        Endpoint& operator=(Endpoint&& other) noexcept {
-            swap(other);
-            return *this;
-        }
-        ~Endpoint() {
-            ALOGE_IF(mHandle != AUDIO_PATCH_HANDLE_NONE,
-                    "A non empty Patch Endpoint leaked, handle %d", mHandle);
-        }
-
-        status_t checkTrack(TrackType *trackOrNull) const {
-            if (trackOrNull == nullptr) return NO_MEMORY;
-            return trackOrNull->initCheck();
-        }
-        audio_patch_handle_t handle() const { return mHandle; }
-        sp<ThreadType> thread() const { return mThread; }
-        sp<TrackType> track() const { return mTrack; }
-        sp<const ThreadType> const_thread() const { return mThread; }
-        sp<const TrackType> const_track() const { return mTrack; }
-
-        void closeConnections(PatchPanel *panel) {
-            if (mHandle != AUDIO_PATCH_HANDLE_NONE) {
-                panel->releaseAudioPatch(mHandle);
-                mHandle = AUDIO_PATCH_HANDLE_NONE;
-            }
-            if (mThread != 0) {
-                if (mTrack != 0) {
-                    mThread->deletePatchTrack(mTrack);
-                }
-                if (mCloseThread) {
-                    panel->mAudioFlinger.closeThreadInternal_l(mThread);
-                }
-            }
-        }
-        audio_patch_handle_t* handlePtr() { return &mHandle; }
-        void setThread(const sp<ThreadType>& thread, bool closeThread = true) {
-            mThread = thread;
-            mCloseThread = closeThread;
-        }
-        template <typename T>
-        void setTrackAndPeer(const sp<TrackType>& track, const sp<T> &peer, bool holdReference) {
-            mTrack = track;
-            mThread->addPatchTrack(mTrack);
-            mTrack->setPeerProxy(peer, holdReference);
-            mClearPeerProxy = holdReference;
-        }
-        void clearTrackPeer() { if (mClearPeerProxy && mTrack) mTrack->clearPeerProxy(); }
-        void stopTrack() { if (mTrack) mTrack->stop(); }
-
-        void swap(Endpoint &other) noexcept {
-            using std::swap;
-            swap(mThread, other.mThread);
-            swap(mCloseThread, other.mCloseThread);
-            swap(mClearPeerProxy, other.mClearPeerProxy);
-            swap(mHandle, other.mHandle);
-            swap(mTrack, other.mTrack);
-        }
-
-        friend void swap(Endpoint &a, Endpoint &b) noexcept {
-            a.swap(b);
-        }
-
-    private:
-        sp<ThreadType> mThread;
-        bool mCloseThread = true;
-        bool mClearPeerProxy = true;
-        audio_patch_handle_t mHandle = AUDIO_PATCH_HANDLE_NONE;
-        sp<TrackType> mTrack;
-    };
-
-    class Patch final {
-    public:
-        Patch(const struct audio_patch &patch, bool endpointPatch) :
-            mAudioPatch(patch), mIsEndpointPatch(endpointPatch) {}
-        Patch() = default;
-        ~Patch();
-        Patch(const Patch& other) noexcept {
-            mAudioPatch = other.mAudioPatch;
-            mHalHandle = other.mHalHandle;
-            mPlayback = other.mPlayback;
-            mRecord = other.mRecord;
-            mThread = other.mThread;
-            mIsEndpointPatch = other.mIsEndpointPatch;
-        }
-        Patch(Patch&& other) noexcept { swap(other); }
-        Patch& operator=(Patch&& other) noexcept {
-            swap(other);
-            return *this;
-        }
-
-        void swap(Patch &other) noexcept {
-            using std::swap;
-            swap(mAudioPatch, other.mAudioPatch);
-            swap(mHalHandle, other.mHalHandle);
-            swap(mPlayback, other.mPlayback);
-            swap(mRecord, other.mRecord);
-            swap(mThread, other.mThread);
-            swap(mIsEndpointPatch, other.mIsEndpointPatch);
-        }
-
-        friend void swap(Patch &a, Patch &b) noexcept {
-            a.swap(b);
-        }
-
-        status_t createConnections(PatchPanel *panel);
-        void clearConnections(PatchPanel *panel);
-        bool isSoftware() const {
-            return mRecord.handle() != AUDIO_PATCH_HANDLE_NONE ||
-                    mPlayback.handle() != AUDIO_PATCH_HANDLE_NONE; }
-
-        void setThread(const sp<ThreadBase>& thread) { mThread = thread; }
-        wp<ThreadBase> thread() const { return mThread; }
-
-        // returns the latency of the patch (from record to playback).
-        status_t getLatencyMs(double *latencyMs) const;
-
-        String8 dump(audio_patch_handle_t myHandle) const;
-
-        // Note that audio_patch::id is only unique within a HAL module
-        struct audio_patch              mAudioPatch;
-        // handle for audio HAL patch handle present only when the audio HAL version is >= 3.0
-        audio_patch_handle_t            mHalHandle = AUDIO_PATCH_HANDLE_NONE;
-        // below members are used by a software audio patch connecting a source device from a
-        // given audio HW module to a sink device on an other audio HW module.
-        // the objects are created by createConnections() and released by clearConnections()
-        // playback thread is created if no existing playback thread can be used
-        // connects playback thread output to sink device
-        Endpoint<PlaybackThread, IAfPatchTrack> mPlayback;
-        // connects source device to record thread input
-        Endpoint<RecordThread, IAfPatchRecord> mRecord;
-
-        wp<ThreadBase> mThread;
-        bool mIsEndpointPatch;
-    };
+    void dump(int fd) const final;
 
     // Call with AudioFlinger mLock held
-    std::map<audio_patch_handle_t, Patch>& patches_l() { return mPatches; }
+    const std::map<audio_patch_handle_t, Patch>& patches_l() const final { return mPatches; }
+
+    // Must be called under AudioFlinger::mLock
+    status_t getLatencyMs_l(audio_patch_handle_t patchHandle, double* latencyMs) const final;
+
+    void closeThreadInternal_l(const sp<IAfThreadBase>& thread) const final;
 
 private:
     AudioHwDevice* findAudioHwDeviceByModule(audio_module_handle_t module);
@@ -297,4 +132,4 @@
     std::map<audio_module_handle_t, ModuleConnections> mInsertedModules;
 };
 
-private:
+}  // namespace android
diff --git a/services/audioflinger/PlaybackTracks.h b/services/audioflinger/PlaybackTracks.h
index 40ed89b..1d50621 100644
--- a/services/audioflinger/PlaybackTracks.h
+++ b/services/audioflinger/PlaybackTracks.h
@@ -17,23 +17,27 @@
 
 #pragma once
 #include <math.h>
+#include <sys/types.h>
 
 namespace android {
 
 // Checks and monitors OP_PLAY_AUDIO
 class OpPlayAudioMonitor : public RefBase {
+    friend class sp<OpPlayAudioMonitor>;
 public:
     ~OpPlayAudioMonitor() override;
     bool hasOpPlayAudio() const;
 
     static sp<OpPlayAudioMonitor> createIfNeeded(
+            IAfThreadBase* thread,
             const AttributionSourceState& attributionSource,
             const audio_attributes_t& attr, int id,
             audio_stream_type_t streamType);
 
 private:
-    OpPlayAudioMonitor(const AttributionSourceState& attributionSource,
-        audio_usage_t usage, int id);
+    OpPlayAudioMonitor(IAfThreadBase* thread,
+                       const AttributionSourceState& attributionSource,
+                       audio_usage_t usage, int id, uid_t uid);
     void onFirstRef() override;
     static void getPackagesForUid(uid_t uid, Vector<String16>& packages);
 
@@ -52,16 +56,19 @@
     // called by PlayAudioOpCallback when OP_PLAY_AUDIO is updated in AppOp callback
     void checkPlayAudioForUsage();
 
+    wp<IAfThreadBase> mThread;
     std::atomic_bool mHasOpPlayAudio;
     const AttributionSourceState mAttributionSource;
     const int32_t mUsage; // on purpose not audio_usage_t because always checked in appOps as int32_t
     const int mId; // for logging purposes only
+    const uid_t mUid;
+    const String16 mPackageName;
 };
 
 // playback track
 class Track : public TrackBase, public virtual IAfTrack, public VolumeProvider {
 public:
-                        Track(AudioFlinger::PlaybackThread* thread,
+    Track(IAfPlaybackThread* thread,
                                 const sp<Client>& client,
                                 audio_stream_type_t streamType,
                                 const audio_attributes_t& attr,
@@ -182,11 +189,7 @@
 
             // This function should be called with holding thread lock.
     void updateTeePatches_l() final;
-    void setTeePatchesToUpdate_l(const void* teePatchesToUpdate) final {
-        setTeePatchesToUpdate_l(  // TODO(b/288339104) void*
-                *reinterpret_cast<const AudioFlinger::TeePatches*>(teePatchesToUpdate));
-    }
-    void setTeePatchesToUpdate_l(AudioFlinger::TeePatches teePatchesToUpdate);
+    void setTeePatchesToUpdate_l(TeePatches teePatchesToUpdate) final;
 
     void tallyUnderrunFrames(size_t frames) final {
        if (isOut()) { // we expect this from output tracks only
@@ -211,11 +214,6 @@
     void processMuteEvent_l(const sp<IAudioManager>& audioManager, mute_state_t muteState) final;
 
 protected:
-    // for numerous
-    friend class PlaybackThread;
-    friend class MixerThread;
-    friend class DirectOutputThread;
-    friend class OffloadThread;
 
     DISALLOW_COPY_AND_ASSIGN(Track);
 
@@ -303,7 +301,7 @@
     mutable FillingStatus mFillingStatus;
     int8_t              mRetryCount;
 
-    // see comment at AudioFlinger::PlaybackThread::Track::~Track for why this can't be const
+    // see comment at ~Track for why this can't be const
     sp<IMemory>         mSharedBuffer;
 
     bool                mResetDone;
@@ -382,8 +380,8 @@
     bool                mFlushHwPending; // track requests for thread flush
     bool                mPauseHwPending = false; // direct/offload track request for thread pause
     audio_output_flags_t mFlags;
-    AudioFlinger::TeePatches  mTeePatches;
-    std::optional<AudioFlinger::TeePatches> mTeePatchesToUpdate;
+    TeePatches mTeePatches;
+    std::optional<TeePatches> mTeePatchesToUpdate;
     const float         mSpeed;
     const bool          mIsSpatialized;
     const bool          mIsBitPerfect;
@@ -404,8 +402,8 @@
         void *mBuffer;
     };
 
-                        OutputTrack(AudioFlinger::PlaybackThread* thread,
-                                AudioFlinger::DuplicatingThread* sourceThread,
+    OutputTrack(IAfPlaybackThread* thread,
+            IAfDuplicatingThread* sourceThread,
                                 uint32_t sampleRate,
                                 audio_format_t format,
                                 audio_channel_mask_t channelMask,
@@ -450,7 +448,7 @@
     Vector < Buffer* >          mBufferQueue;
     AudioBufferProvider::Buffer mOutBuffer;
     bool                        mActive;
-    AudioFlinger::DuplicatingThread* const mSourceThread; // for waitTimeMs() in write()
+    IAfDuplicatingThread* const mSourceThread; // for waitTimeMs() in write()
     sp<AudioTrackClientProxy>   mClientProxy;
 
     /** Attributes of the source tracks.
@@ -472,7 +470,7 @@
 // playback track, used by PatchPanel
 class PatchTrack : public Track, public PatchTrackBase, public IAfPatchTrack {
 public:
-                        PatchTrack(AudioFlinger::PlaybackThread* playbackThread,
+    PatchTrack(IAfPlaybackThread* playbackThread,
                                    audio_stream_type_t streamType,
                                    uint32_t sampleRate,
                                    audio_channel_mask_t channelMask,
diff --git a/services/audioflinger/RecordTracks.h b/services/audioflinger/RecordTracks.h
index 9d25ba4..89e2f66 100644
--- a/services/audioflinger/RecordTracks.h
+++ b/services/audioflinger/RecordTracks.h
@@ -24,7 +24,7 @@
 // record track
 class RecordTrack : public TrackBase, public virtual IAfRecordTrack {
 public:
-                        RecordTrack(AudioFlinger::RecordThread* thread,
+    RecordTrack(IAfRecordThread* thread,
                                 const sp<Client>& client,
                                 const audio_attributes_t& attr,
                                 uint32_t sampleRate,
@@ -95,8 +95,6 @@
     }
 
 private:
-    friend class AudioFlinger;  // for mState
-
     DISALLOW_COPY_AND_ASSIGN(RecordTrack);
 
 protected:
@@ -133,7 +131,7 @@
 // playback track, used by PatchPanel
 class PatchRecord : public RecordTrack, public PatchTrackBase, public IAfPatchRecord {
 public:
-    PatchRecord(AudioFlinger::RecordThread* recordThread,
+    PatchRecord(IAfRecordThread* recordThread,
                 uint32_t sampleRate,
                 audio_channel_mask_t channelMask,
                 audio_format_t format,
@@ -169,7 +167,7 @@
 
 class PassthruPatchRecord : public PatchRecord, public Source {
 public:
-    PassthruPatchRecord(AudioFlinger::RecordThread* recordThread,
+    PassthruPatchRecord(IAfRecordThread* recordThread,
                         uint32_t sampleRate,
                         audio_channel_mask_t channelMask,
                         audio_format_t format,
@@ -212,7 +210,7 @@
         PassthruPatchRecord& mPassthru;
     };
 
-    sp<StreamInHalInterface> obtainStream(sp<AudioFlinger::ThreadBase>* thread);
+    sp<StreamInHalInterface> obtainStream(sp<IAfThreadBase>* thread);
 
     PatchRecordAudioBufferProvider mPatchRecordAudioBufferProvider;
     std::unique_ptr<void, decltype(free)*> mSinkBuffer;  // frame size aligned continuous buffer
diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index 14e4aab..9e29ba3 100644
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -76,6 +76,8 @@
 #include <media/audiohal/StreamHalInterface.h>
 
 #include "AudioFlinger.h"
+#include "Threads.h"
+
 #include <mediautils/SchedulingPolicyService.h>
 #include <mediautils/ServiceUtilities.h>
 
@@ -120,6 +122,7 @@
 
 namespace android {
 
+using audioflinger::SyncEvent;
 using media::IEffectClient;
 using content::AttributionSourceState;
 
@@ -515,7 +518,7 @@
 // ----------------------------------------------------------------------------
 
 // static
-const char *AudioFlinger::ThreadBase::threadTypeToString(AudioFlinger::ThreadBase::type_t type)
+const char* ThreadBase::threadTypeToString(ThreadBase::type_t type)
 {
     switch (type) {
     case MIXER:
@@ -541,7 +544,7 @@
     }
 }
 
-AudioFlinger::ThreadBase::ThreadBase(const sp<AudioFlinger>& audioFlinger, audio_io_handle_t id,
+ThreadBase::ThreadBase(const sp<AudioFlinger>& audioFlinger, audio_io_handle_t id,
         type_t type, bool systemReady, bool isOut)
     :   Thread(false /*canCallJava*/),
         mType(type),
@@ -564,7 +567,7 @@
     memset(&mPatch, 0, sizeof(struct audio_patch));
 }
 
-AudioFlinger::ThreadBase::~ThreadBase()
+ThreadBase::~ThreadBase()
 {
     // mConfigEvents should be empty, but just in case it isn't, free the memory it owns
     mConfigEvents.clear();
@@ -579,7 +582,7 @@
     sendStatistics(true /* force */);
 }
 
-status_t AudioFlinger::ThreadBase::readyToRun()
+status_t ThreadBase::readyToRun()
 {
     status_t status = initCheck();
     if (status == NO_ERROR) {
@@ -590,7 +593,7 @@
     return status;
 }
 
-void AudioFlinger::ThreadBase::exit()
+void ThreadBase::exit()
 {
     ALOGV("ThreadBase::exit");
     // do any cleanup required for exit to succeed
@@ -614,7 +617,7 @@
     requestExitAndWait();
 }
 
-status_t AudioFlinger::ThreadBase::setParameters(const String8& keyValuePairs)
+status_t ThreadBase::setParameters(const String8& keyValuePairs)
 {
     ALOGV("ThreadBase::setParameters() %s", keyValuePairs.string());
     Mutex::Autolock _l(mLock);
@@ -624,7 +627,7 @@
 
 // sendConfigEvent_l() must be called with ThreadBase::mLock held
 // Can temporarily release the lock if waiting for a reply from processConfigEvents_l().
-status_t AudioFlinger::ThreadBase::sendConfigEvent_l(sp<ConfigEvent>& event)
+status_t ThreadBase::sendConfigEvent_l(sp<ConfigEvent>& event)
 NO_THREAD_SAFETY_ANALYSIS  // condition variable
 {
     status_t status = NO_ERROR;
@@ -652,7 +655,7 @@
     return status;
 }
 
-void AudioFlinger::ThreadBase::sendIoConfigEvent(audio_io_config_event_t event, pid_t pid,
+void ThreadBase::sendIoConfigEvent(audio_io_config_event_t event, pid_t pid,
                                                  audio_port_handle_t portId)
 {
     Mutex::Autolock _l(mLock);
@@ -660,7 +663,7 @@
 }
 
 // sendIoConfigEvent_l() must be called with ThreadBase::mLock held
-void AudioFlinger::ThreadBase::sendIoConfigEvent_l(audio_io_config_event_t event, pid_t pid,
+void ThreadBase::sendIoConfigEvent_l(audio_io_config_event_t event, pid_t pid,
                                                    audio_port_handle_t portId)
 {
     // The audio statistics history is exponentially weighted to forget events
@@ -677,14 +680,14 @@
     sendConfigEvent_l(configEvent);
 }
 
-void AudioFlinger::ThreadBase::sendPrioConfigEvent(pid_t pid, pid_t tid, int32_t prio, bool forApp)
+void ThreadBase::sendPrioConfigEvent(pid_t pid, pid_t tid, int32_t prio, bool forApp)
 {
     Mutex::Autolock _l(mLock);
     sendPrioConfigEvent_l(pid, tid, prio, forApp);
 }
 
 // sendPrioConfigEvent_l() must be called with ThreadBase::mLock held
-void AudioFlinger::ThreadBase::sendPrioConfigEvent_l(
+void ThreadBase::sendPrioConfigEvent_l(
         pid_t pid, pid_t tid, int32_t prio, bool forApp)
 {
     sp<ConfigEvent> configEvent = (ConfigEvent *)new PrioConfigEvent(pid, tid, prio, forApp);
@@ -692,7 +695,7 @@
 }
 
 // sendSetParameterConfigEvent_l() must be called with ThreadBase::mLock held
-status_t AudioFlinger::ThreadBase::sendSetParameterConfigEvent_l(const String8& keyValuePair)
+status_t ThreadBase::sendSetParameterConfigEvent_l(const String8& keyValuePair)
 {
     sp<ConfigEvent> configEvent;
     AudioParameter param(keyValuePair);
@@ -710,7 +713,7 @@
     return sendConfigEvent_l(configEvent);
 }
 
-status_t AudioFlinger::ThreadBase::sendCreateAudioPatchConfigEvent(
+status_t ThreadBase::sendCreateAudioPatchConfigEvent(
                                                         const struct audio_patch *patch,
                                                         audio_patch_handle_t *handle)
 {
@@ -725,7 +728,7 @@
     return status;
 }
 
-status_t AudioFlinger::ThreadBase::sendReleaseAudioPatchConfigEvent(
+status_t ThreadBase::sendReleaseAudioPatchConfigEvent(
                                                                 const audio_patch_handle_t handle)
 {
     Mutex::Autolock _l(mLock);
@@ -733,7 +736,7 @@
     return sendConfigEvent_l(configEvent);
 }
 
-status_t AudioFlinger::ThreadBase::sendUpdateOutDeviceConfigEvent(
+status_t ThreadBase::sendUpdateOutDeviceConfigEvent(
         const DeviceDescriptorBaseVector& outDevices)
 {
     if (type() != RECORD) {
@@ -745,7 +748,7 @@
     return sendConfigEvent_l(configEvent);
 }
 
-void AudioFlinger::ThreadBase::sendResizeBufferConfigEvent_l(int32_t maxSharedAudioHistoryMs)
+void ThreadBase::sendResizeBufferConfigEvent_l(int32_t maxSharedAudioHistoryMs)
 {
     ALOG_ASSERT(type() == RECORD, "sendResizeBufferConfigEvent_l() called on non record thread");
     sp<ConfigEvent> configEvent =
@@ -753,27 +756,27 @@
     sendConfigEvent_l(configEvent);
 }
 
-void AudioFlinger::ThreadBase::sendCheckOutputStageEffectsEvent()
+void ThreadBase::sendCheckOutputStageEffectsEvent()
 {
     Mutex::Autolock _l(mLock);
     sendCheckOutputStageEffectsEvent_l();
 }
 
-void AudioFlinger::ThreadBase::sendCheckOutputStageEffectsEvent_l()
+void ThreadBase::sendCheckOutputStageEffectsEvent_l()
 {
     sp<ConfigEvent> configEvent =
             (ConfigEvent *)new CheckOutputStageEffectsEvent();
     sendConfigEvent_l(configEvent);
 }
 
-void AudioFlinger::ThreadBase::sendHalLatencyModesChangedEvent_l()
+void ThreadBase::sendHalLatencyModesChangedEvent_l()
 {
     sp<ConfigEvent> configEvent = sp<HalLatencyModesChangedEvent>::make();
     sendConfigEvent_l(configEvent);
 }
 
 // post condition: mConfigEvents.isEmpty()
-void AudioFlinger::ThreadBase::processConfigEvents_l()
+void ThreadBase::processConfigEvents_l()
 {
     bool configChanged = false;
 
@@ -940,7 +943,7 @@
     }
 }
 
-void AudioFlinger::ThreadBase::dump(int fd, const Vector<String16>& args)
+void ThreadBase::dump(int fd, const Vector<String16>& args)
 NO_THREAD_SAFETY_ANALYSIS  // conditional try lock
 {
     dprintf(fd, "\n%s thread %p, name %s, tid %d, type %d (%s):\n", isOutput() ? "Output" : "Input",
@@ -978,7 +981,7 @@
     }
 }
 
-void AudioFlinger::ThreadBase::dumpBase_l(int fd, const Vector<String16>& args __unused)
+void ThreadBase::dumpBase_l(int fd, const Vector<String16>& /* args */)
 {
     dprintf(fd, "  I/O handle: %d\n", mId);
     dprintf(fd, "  Standby: %s\n", mStandby ? "yes" : "no");
@@ -1051,7 +1054,7 @@
     }
 }
 
-void AudioFlinger::ThreadBase::dumpEffectChains_l(int fd, const Vector<String16>& args)
+void ThreadBase::dumpEffectChains_l(int fd, const Vector<String16>& args)
 {
     const size_t SIZE = 256;
     char buffer[SIZE];
@@ -1068,13 +1071,13 @@
     }
 }
 
-void AudioFlinger::ThreadBase::acquireWakeLock()
+void ThreadBase::acquireWakeLock()
 {
     Mutex::Autolock _l(mLock);
     acquireWakeLock_l();
 }
 
-String16 AudioFlinger::ThreadBase::getWakeLockTag()
+String16 ThreadBase::getWakeLockTag()
 {
     switch (mType) {
     case MIXER:
@@ -1099,7 +1102,7 @@
     }
 }
 
-void AudioFlinger::ThreadBase::acquireWakeLock_l()
+void ThreadBase::acquireWakeLock_l()
 {
     getPowerManager_l();
     if (mPowerManager != 0) {
@@ -1122,13 +1125,13 @@
             gBoottime.getBoottimeOffset();
 }
 
-void AudioFlinger::ThreadBase::releaseWakeLock()
+void ThreadBase::releaseWakeLock()
 {
     Mutex::Autolock _l(mLock);
     releaseWakeLock_l();
 }
 
-void AudioFlinger::ThreadBase::releaseWakeLock_l()
+void ThreadBase::releaseWakeLock_l()
 {
     gBoottime.release(mWakeLockToken);
     if (mWakeLockToken != 0) {
@@ -1140,7 +1143,7 @@
     }
 }
 
-void AudioFlinger::ThreadBase::getPowerManager_l() {
+void ThreadBase::getPowerManager_l() {
     if (mSystemReady && mPowerManager == 0) {
         // use checkService() to avoid blocking if power service is not up yet
         sp<IBinder> binder =
@@ -1154,7 +1157,7 @@
     }
 }
 
-void AudioFlinger::ThreadBase::updateWakeLockUids_l(const SortedVector<uid_t> &uids) {
+void ThreadBase::updateWakeLockUids_l(const SortedVector<uid_t>& uids) {
     getPowerManager_l();
 
 #if !LOG_NDEBUG
@@ -1181,25 +1184,25 @@
     }
 }
 
-void AudioFlinger::ThreadBase::clearPowerManager()
+void ThreadBase::clearPowerManager()
 {
     Mutex::Autolock _l(mLock);
     releaseWakeLock_l();
     mPowerManager.clear();
 }
 
-void AudioFlinger::ThreadBase::updateOutDevices(
+void ThreadBase::updateOutDevices(
         const DeviceDescriptorBaseVector& outDevices __unused)
 {
     ALOGE("%s should only be called in RecordThread", __func__);
 }
 
-void AudioFlinger::ThreadBase::resizeInputBuffer_l(int32_t maxSharedAudioHistoryMs __unused)
+void ThreadBase::resizeInputBuffer_l(int32_t /* maxSharedAudioHistoryMs */)
 {
     ALOGE("%s should only be called in RecordThread", __func__);
 }
 
-void AudioFlinger::ThreadBase::PMDeathRecipient::binderDied(const wp<IBinder>& who __unused)
+void ThreadBase::PMDeathRecipient::binderDied(const wp<IBinder>& /* who */)
 {
     sp<ThreadBase> thread = mThread.promote();
     if (thread != 0) {
@@ -1208,7 +1211,7 @@
     ALOGW("power manager service died !!!");
 }
 
-void AudioFlinger::ThreadBase::setEffectSuspended_l(
+void ThreadBase::setEffectSuspended_l(
         const effect_uuid_t *type, bool suspend, audio_session_t sessionId)
 {
     sp<IAfEffectChain> chain = getEffectChain_l(sessionId);
@@ -1223,7 +1226,7 @@
     updateSuspendedSessions_l(type, suspend, sessionId);
 }
 
-void AudioFlinger::ThreadBase::checkSuspendOnAddEffectChain_l(const sp<IAfEffectChain>& chain)
+void ThreadBase::checkSuspendOnAddEffectChain_l(const sp<IAfEffectChain>& chain)
 {
     ssize_t index = mSuspendedSessions.indexOfKey(chain->sessionId());
     if (index < 0) {
@@ -1247,7 +1250,7 @@
     }
 }
 
-void AudioFlinger::ThreadBase::updateSuspendedSessions_l(const effect_uuid_t *type,
+void ThreadBase::updateSuspendedSessions_l(const effect_uuid_t* type,
                                                          bool suspend,
                                                          audio_session_t sessionId)
 {
@@ -1308,7 +1311,7 @@
     }
 }
 
-void AudioFlinger::ThreadBase::checkSuspendOnEffectEnabled(bool enabled,
+void ThreadBase::checkSuspendOnEffectEnabled(bool enabled,
                                                            audio_session_t sessionId,
                                                            bool threadLocked)
 NO_THREAD_SAFETY_ANALYSIS  // manual locking
@@ -1334,7 +1337,7 @@
 }
 
 // checkEffectCompatibility_l() must be called with ThreadBase::mLock held
-status_t AudioFlinger::RecordThread::checkEffectCompatibility_l(
+status_t RecordThread::checkEffectCompatibility_l(
         const effect_descriptor_t *desc, audio_session_t sessionId)
 {
     // No global output effect sessions on record threads
@@ -1378,7 +1381,7 @@
 }
 
 // checkEffectCompatibility_l() must be called with ThreadBase::mLock held
-status_t AudioFlinger::PlaybackThread::checkEffectCompatibility_l(
+status_t PlaybackThread::checkEffectCompatibility_l(
         const effect_descriptor_t *desc, audio_session_t sessionId)
 {
     // no preprocessing on playback threads
@@ -1533,7 +1536,7 @@
 }
 
 // ThreadBase::createEffect_l() must be called with AudioFlinger::mLock held
-sp<IAfEffectHandle> AudioFlinger::ThreadBase::createEffect_l(
+sp<IAfEffectHandle> ThreadBase::createEffect_l(
         const sp<Client>& client,
         const sp<IEffectClient>& effectClient,
         int32_t priority,
@@ -1638,7 +1641,7 @@
     return handle;
 }
 
-void AudioFlinger::ThreadBase::disconnectEffectHandle(IAfEffectHandle *handle,
+void ThreadBase::disconnectEffectHandle(IAfEffectHandle* handle,
                                                       bool unpinIfLast)
 {
     bool remove = false;
@@ -1668,7 +1671,7 @@
     }
 }
 
-void AudioFlinger::ThreadBase::onEffectEnable(const sp<IAfEffectModule>& effect) {
+void ThreadBase::onEffectEnable(const sp<IAfEffectModule>& effect) {
     if (isOffloadOrMmap()) {
         Mutex::Autolock _l(mLock);
         broadcast_l();
@@ -1684,28 +1687,28 @@
     }
 }
 
-void AudioFlinger::ThreadBase::onEffectDisable() {
+void ThreadBase::onEffectDisable() {
     if (isOffloadOrMmap()) {
         Mutex::Autolock _l(mLock);
         broadcast_l();
     }
 }
 
-sp<IAfEffectModule> AudioFlinger::ThreadBase::getEffect(audio_session_t sessionId,
-        int effectId)
+sp<IAfEffectModule> ThreadBase::getEffect(audio_session_t sessionId,
+        int effectId) const
 {
     Mutex::Autolock _l(mLock);
     return getEffect_l(sessionId, effectId);
 }
 
-sp<IAfEffectModule> AudioFlinger::ThreadBase::getEffect_l(audio_session_t sessionId,
-        int effectId)
+sp<IAfEffectModule> ThreadBase::getEffect_l(audio_session_t sessionId,
+        int effectId) const
 {
     sp<IAfEffectChain> chain = getEffectChain_l(sessionId);
     return chain != 0 ? chain->getEffectFromId_l(effectId) : 0;
 }
 
-std::vector<int> AudioFlinger::ThreadBase::getEffectIds_l(audio_session_t sessionId)
+std::vector<int> ThreadBase::getEffectIds_l(audio_session_t sessionId) const
 {
     sp<IAfEffectChain> chain = getEffectChain_l(sessionId);
     return chain != nullptr ? chain->getEffectIds() : std::vector<int>{};
@@ -1713,7 +1716,7 @@
 
 // PlaybackThread::addEffect_l() must be called with AudioFlinger::mLock and
 // PlaybackThread::mLock held
-status_t AudioFlinger::ThreadBase::addEffect_l(const sp<IAfEffectModule>& effect)
+status_t ThreadBase::addEffect_l(const sp<IAfEffectModule>& effect)
 {
     // check for existing effect chain with the requested audio session
     audio_session_t sessionId = effect->sessionId();
@@ -1758,7 +1761,7 @@
     return NO_ERROR;
 }
 
-void AudioFlinger::ThreadBase::removeEffect_l(const sp<IAfEffectModule>& effect, bool release) {
+void ThreadBase::removeEffect_l(const sp<IAfEffectModule>& effect, bool release) {
 
     ALOGV("%s %p effect %p", __FUNCTION__, this, effect.get());
     effect_descriptor_t desc = effect->desc();
@@ -1777,7 +1780,7 @@
     }
 }
 
-void AudioFlinger::ThreadBase::lockEffectChains_l(
+void ThreadBase::lockEffectChains_l(
         Vector<sp<IAfEffectChain>>& effectChains)
 NO_THREAD_SAFETY_ANALYSIS  // calls EffectChain::lock()
 {
@@ -1787,7 +1790,7 @@
     }
 }
 
-void AudioFlinger::ThreadBase::unlockEffectChains(
+void ThreadBase::unlockEffectChains(
         const Vector<sp<IAfEffectChain>>& effectChains)
 NO_THREAD_SAFETY_ANALYSIS  // calls EffectChain::unlock()
 {
@@ -1796,13 +1799,13 @@
     }
 }
 
-sp<IAfEffectChain> AudioFlinger::ThreadBase::getEffectChain(audio_session_t sessionId)
+sp<IAfEffectChain> ThreadBase::getEffectChain(audio_session_t sessionId) const
 {
     Mutex::Autolock _l(mLock);
     return getEffectChain_l(sessionId);
 }
 
-sp<IAfEffectChain> AudioFlinger::ThreadBase::getEffectChain_l(audio_session_t sessionId)
+sp<IAfEffectChain> ThreadBase::getEffectChain_l(audio_session_t sessionId)
         const
 {
     size_t size = mEffectChains.size();
@@ -1814,7 +1817,7 @@
     return 0;
 }
 
-void AudioFlinger::ThreadBase::setMode(audio_mode_t mode)
+void ThreadBase::setMode(audio_mode_t mode)
 {
     Mutex::Autolock _l(mLock);
     size_t size = mEffectChains.size();
@@ -1823,7 +1826,7 @@
     }
 }
 
-void AudioFlinger::ThreadBase::toAudioPortConfig(struct audio_port_config *config)
+void ThreadBase::toAudioPortConfig(struct audio_port_config* config)
 {
     config->type = AUDIO_PORT_TYPE_MIX;
     config->ext.mix.handle = mId;
@@ -1834,7 +1837,7 @@
                             AUDIO_PORT_CONFIG_FORMAT;
 }
 
-void AudioFlinger::ThreadBase::systemReady()
+void ThreadBase::systemReady()
 {
     Mutex::Autolock _l(mLock);
     if (mSystemReady) {
@@ -1849,7 +1852,7 @@
 }
 
 template <typename T>
-ssize_t AudioFlinger::ThreadBase::ActiveTracks<T>::add(const sp<T> &track) {
+ssize_t ThreadBase::ActiveTracks<T>::add(const sp<T>& track) {
     ssize_t index = mActiveTracks.indexOf(track);
     if (index >= 0) {
         ALOGW("ActiveTracks<T>::add track %p already there", track.get());
@@ -1864,7 +1867,7 @@
 }
 
 template <typename T>
-ssize_t AudioFlinger::ThreadBase::ActiveTracks<T>::remove(const sp<T> &track) {
+ssize_t ThreadBase::ActiveTracks<T>::remove(const sp<T>& track) {
     ssize_t index = mActiveTracks.remove(track);
     if (index < 0) {
         ALOGW("ActiveTracks<T>::remove nonexistent track %p", track.get());
@@ -1883,7 +1886,7 @@
 }
 
 template <typename T>
-void AudioFlinger::ThreadBase::ActiveTracks<T>::clear() {
+void ThreadBase::ActiveTracks<T>::clear() {
     for (const sp<T> &track : mActiveTracks) {
         track->endBatteryAttribution();
         logTrack("clear", track);
@@ -1895,7 +1898,7 @@
 }
 
 template <typename T>
-void AudioFlinger::ThreadBase::ActiveTracks<T>::updatePowerState(
+void ThreadBase::ActiveTracks<T>::updatePowerState(
         const sp<ThreadBase>& thread, bool force) {
     // Updates ActiveTracks client uids to the thread wakelock.
     if (mActiveTracksGeneration != mLastActiveTracksGeneration || force) {
@@ -1905,7 +1908,7 @@
 }
 
 template <typename T>
-bool AudioFlinger::ThreadBase::ActiveTracks<T>::readAndClearHasChanged() {
+bool ThreadBase::ActiveTracks<T>::readAndClearHasChanged() {
     bool hasChanged = mHasChanged;
     mHasChanged = false;
 
@@ -1918,7 +1921,7 @@
 }
 
 template <typename T>
-void AudioFlinger::ThreadBase::ActiveTracks<T>::logTrack(
+void ThreadBase::ActiveTracks<T>::logTrack(
         const char *funcName, const sp<T> &track) const {
     if (mLocalLog != nullptr) {
         String8 result;
@@ -1927,7 +1930,7 @@
     }
 }
 
-void AudioFlinger::ThreadBase::broadcast_l()
+void ThreadBase::broadcast_l()
 {
     // Thread could be blocked waiting for async
     // so signal it to handle state changes immediately
@@ -1939,7 +1942,7 @@
 
 // Call only from threadLoop() or when it is idle.
 // Do not call from high performance code as this may do binder rpc to the MediaMetrics service.
-void AudioFlinger::ThreadBase::sendStatistics(bool force)
+void ThreadBase::sendStatistics(bool force)
 {
     // Do not log if we have no stats.
     // We choose the timestamp verifier because it is the most likely item to be present.
@@ -2002,7 +2005,7 @@
     item->selfrecord();
 }
 
-product_strategy_t AudioFlinger::ThreadBase::getStrategyForStream(audio_stream_type_t stream) const
+product_strategy_t ThreadBase::getStrategyForStream(audio_stream_type_t stream) const
 {
     if (!mAudioFlinger->isAudioPolicyReady()) {
         return PRODUCT_STRATEGY_NONE;
@@ -2011,7 +2014,7 @@
 }
 
 // startMelComputation_l() must be called with AudioFlinger::mLock held
-void AudioFlinger::ThreadBase::startMelComputation_l(
+void ThreadBase::startMelComputation_l(
         const sp<audio_utils::MelProcessor>& /*processor*/)
 {
     // Do nothing
@@ -2019,7 +2022,7 @@
 }
 
 // stopMelComputation_l() must be called with AudioFlinger::mLock held
-void AudioFlinger::ThreadBase::stopMelComputation_l()
+void ThreadBase::stopMelComputation_l()
 {
     // Do nothing
     ALOGW("%s: ThreadBase does not support CSD", __func__);
@@ -2029,7 +2032,7 @@
 //      Playback
 // ----------------------------------------------------------------------------
 
-AudioFlinger::PlaybackThread::PlaybackThread(const sp<AudioFlinger>& audioFlinger,
+PlaybackThread::PlaybackThread(const sp<AudioFlinger>& audioFlinger,
                                              AudioStreamOut* output,
                                              audio_io_handle_t id,
                                              type_t type,
@@ -2129,7 +2132,7 @@
     mStreamTypes[AUDIO_STREAM_CALL_ASSISTANT].mute = false;
 }
 
-AudioFlinger::PlaybackThread::~PlaybackThread()
+PlaybackThread::~PlaybackThread()
 {
     mAudioFlinger->unregisterWriter(mNBLogWriter);
     free(mSinkBuffer);
@@ -2140,7 +2143,7 @@
 
 // Thread virtuals
 
-void AudioFlinger::PlaybackThread::onFirstRef()
+void PlaybackThread::onFirstRef()
 {
     if (!isStreamInitialized()) {
         ALOGE("The stream is not open yet"); // This should not happen.
@@ -2155,7 +2158,7 @@
         if (mOutput->flags & AUDIO_OUTPUT_FLAG_NON_BLOCKING &&
                 mOutput->stream->setCallback(this) == OK) {
             mUseAsyncWrite = true;
-            mCallbackThread = new AudioFlinger::AsyncCallbackThread(this);
+            mCallbackThread = sp<AsyncCallbackThread>::make(this);
         }
 
         if (mOutput->stream->setEventCallback(this) != OK) {
@@ -2167,14 +2170,14 @@
 }
 
 // ThreadBase virtuals
-void AudioFlinger::PlaybackThread::preExit()
+void PlaybackThread::preExit()
 {
     ALOGV("  preExit()");
     status_t result = mOutput->stream->exit();
     ALOGE_IF(result != OK, "Error when calling exit(): %d", result);
 }
 
-void AudioFlinger::PlaybackThread::dumpTracks_l(int fd, const Vector<String16>& args __unused)
+void PlaybackThread::dumpTracks_l(int fd, const Vector<String16>& /* args */)
 {
     String8 result;
 
@@ -2239,7 +2242,7 @@
     write(fd, result.string(), result.size());
 }
 
-void AudioFlinger::PlaybackThread::dumpInternals_l(int fd, const Vector<String16>& args)
+void PlaybackThread::dumpInternals_l(int fd, const Vector<String16>& args)
 {
     dprintf(fd, "  Master volume: %f\n", mMasterVolume);
     dprintf(fd, "  Master mute: %s\n", mMasterMute ? "on" : "off");
@@ -2275,7 +2278,7 @@
 }
 
 // PlaybackThread::createTrack_l() must be called with AudioFlinger::mLock held
-sp<IAfTrack> AudioFlinger::PlaybackThread::createTrack_l(
+sp<IAfTrack> PlaybackThread::createTrack_l(
         const sp<Client>& client,
         audio_stream_type_t streamType,
         const audio_attributes_t& attr,
@@ -2660,7 +2663,7 @@
 }
 
 template<typename T>
-ssize_t AudioFlinger::PlaybackThread::Tracks<T>::remove(const sp<T> &track)
+ssize_t PlaybackThread::Tracks<T>::remove(const sp<T>& track)
 {
     const int trackId = track->id();
     const ssize_t index = mTracks.remove(track);
@@ -2675,17 +2678,17 @@
     return index;
 }
 
-uint32_t AudioFlinger::PlaybackThread::correctLatency_l(uint32_t latency) const
+uint32_t PlaybackThread::correctLatency_l(uint32_t latency) const
 {
     return latency;
 }
 
-uint32_t AudioFlinger::PlaybackThread::latency() const
+uint32_t PlaybackThread::latency() const
 {
     Mutex::Autolock _l(mLock);
     return latency_l();
 }
-uint32_t AudioFlinger::PlaybackThread::latency_l() const
+uint32_t PlaybackThread::latency_l() const
 {
     uint32_t latency;
     if (initCheck() == NO_ERROR && mOutput->stream->getLatency(&latency) == OK) {
@@ -2694,7 +2697,7 @@
     return 0;
 }
 
-void AudioFlinger::PlaybackThread::setMasterVolume(float value)
+void PlaybackThread::setMasterVolume(float value)
 {
     Mutex::Autolock _l(mLock);
     // Don't apply master volume in SW if our HAL can do it for us.
@@ -2706,12 +2709,12 @@
     }
 }
 
-void AudioFlinger::PlaybackThread::setMasterBalance(float balance)
+void PlaybackThread::setMasterBalance(float balance)
 {
     mMasterBalance.store(balance);
 }
 
-void AudioFlinger::PlaybackThread::setMasterMute(bool muted)
+void PlaybackThread::setMasterMute(bool muted)
 {
     if (isDuplicating()) {
         return;
@@ -2726,33 +2729,33 @@
     }
 }
 
-void AudioFlinger::PlaybackThread::setStreamVolume(audio_stream_type_t stream, float value)
+void PlaybackThread::setStreamVolume(audio_stream_type_t stream, float value)
 {
     Mutex::Autolock _l(mLock);
     mStreamTypes[stream].volume = value;
     broadcast_l();
 }
 
-void AudioFlinger::PlaybackThread::setStreamMute(audio_stream_type_t stream, bool muted)
+void PlaybackThread::setStreamMute(audio_stream_type_t stream, bool muted)
 {
     Mutex::Autolock _l(mLock);
     mStreamTypes[stream].mute = muted;
     broadcast_l();
 }
 
-float AudioFlinger::PlaybackThread::streamVolume(audio_stream_type_t stream) const
+float PlaybackThread::streamVolume(audio_stream_type_t stream) const
 {
     Mutex::Autolock _l(mLock);
     return mStreamTypes[stream].volume;
 }
 
-void AudioFlinger::PlaybackThread::setVolumeForOutput_l(float left, float right) const
+void PlaybackThread::setVolumeForOutput_l(float left, float right) const
 {
     mOutput->stream->setVolume(left, right);
 }
 
 // addTrack_l() must be called with ThreadBase::mLock held
-status_t AudioFlinger::PlaybackThread::addTrack_l(const sp<IAfTrack>& track)
+status_t PlaybackThread::addTrack_l(const sp<IAfTrack>& track)
 NO_THREAD_SAFETY_ANALYSIS  // release and re-acquire mLock
 {
     status_t status = ALREADY_EXISTS;
@@ -2858,7 +2861,7 @@
     return status;
 }
 
-bool AudioFlinger::PlaybackThread::destroyTrack_l(const sp<IAfTrack>& track)
+bool PlaybackThread::destroyTrack_l(const sp<IAfTrack>& track)
 {
     track->terminate();
     // active tracks are removed by threadLoop()
@@ -2876,7 +2879,7 @@
     return trackActive;
 }
 
-void AudioFlinger::PlaybackThread::removeTrack_l(const sp<IAfTrack>& track)
+void PlaybackThread::removeTrack_l(const sp<IAfTrack>& track)
 {
     track->triggerEvents(AudioSystem::SYNC_EVENT_PRESENTATION_COMPLETE);
 
@@ -2903,7 +2906,7 @@
     }
 }
 
-String8 AudioFlinger::PlaybackThread::getParameters(const String8& keys)
+String8 PlaybackThread::getParameters(const String8& keys)
 {
     Mutex::Autolock _l(mLock);
     String8 out_s8;
@@ -2913,7 +2916,7 @@
     return {};
 }
 
-status_t AudioFlinger::DirectOutputThread::selectPresentation(int presentationId, int programId) {
+status_t DirectOutputThread::selectPresentation(int presentationId, int programId) {
     Mutex::Autolock _l(mLock);
     if (!isStreamInitialized()) {
         return NO_INIT;
@@ -2921,7 +2924,7 @@
     return mOutput->stream->selectPresentation(presentationId, programId);
 }
 
-void AudioFlinger::PlaybackThread::ioConfigChanged(audio_io_config_event_t event, pid_t pid,
+void PlaybackThread::ioConfigChanged(audio_io_config_event_t event, pid_t pid,
                                                    audio_port_handle_t portId) {
     ALOGV("PlaybackThread::ioConfigChanged, thread %p, event %d", this, event);
     sp<AudioIoDescriptor> desc;
@@ -2946,27 +2949,27 @@
     mAudioFlinger->ioConfigChanged(event, desc, pid);
 }
 
-void AudioFlinger::PlaybackThread::onWriteReady()
+void PlaybackThread::onWriteReady()
 {
     mCallbackThread->resetWriteBlocked();
 }
 
-void AudioFlinger::PlaybackThread::onDrainReady()
+void PlaybackThread::onDrainReady()
 {
     mCallbackThread->resetDraining();
 }
 
-void AudioFlinger::PlaybackThread::onError()
+void PlaybackThread::onError()
 {
     mCallbackThread->setAsyncError();
 }
 
-void AudioFlinger::PlaybackThread::onCodecFormatChanged(
+void PlaybackThread::onCodecFormatChanged(
         const std::basic_string<uint8_t>& metadataBs)
 {
-    wp<AudioFlinger::PlaybackThread> weakPointerThis = this;
+    const auto weakPointerThis = wp<PlaybackThread>::fromExisting(this);
     std::thread([this, metadataBs, weakPointerThis]() {
-            sp<AudioFlinger::PlaybackThread> playbackThread = weakPointerThis.promote();
+            const sp<PlaybackThread> playbackThread = weakPointerThis.promote();
             if (playbackThread == nullptr) {
                 ALOGW("PlaybackThread was destroyed, skip codec format change event");
                 return;
@@ -2991,7 +2994,7 @@
     }).detach();
 }
 
-void AudioFlinger::PlaybackThread::resetWriteBlocked(uint32_t sequence)
+void PlaybackThread::resetWriteBlocked(uint32_t sequence)
 {
     Mutex::Autolock _l(mLock);
     // reject out of sequence requests
@@ -3001,7 +3004,7 @@
     }
 }
 
-void AudioFlinger::PlaybackThread::resetDraining(uint32_t sequence)
+void PlaybackThread::resetDraining(uint32_t sequence)
 {
     Mutex::Autolock _l(mLock);
     // reject out of sequence requests
@@ -3016,7 +3019,7 @@
     }
 }
 
-void AudioFlinger::PlaybackThread::readOutputParameters_l()
+void PlaybackThread::readOutputParameters_l()
 {
     // unfortunately we have no way of recovering from errors here, hence the LOG_ALWAYS_FATAL
     const audio_config_base_t audioConfig = mOutput->getAudioProperties();
@@ -3025,7 +3028,7 @@
     if (!audio_is_output_channel(mChannelMask)) {
         LOG_ALWAYS_FATAL("HAL channel mask %#x not valid for output", mChannelMask);
     }
-    if (hasMixer() && !isValidPcmSinkChannelMask(mChannelMask)) {
+    if (hasMixer() && !AudioFlinger::isValidPcmSinkChannelMask(mChannelMask)) {
         LOG_ALWAYS_FATAL("HAL channel mask %#x not supported for mixed output",
                 mChannelMask);
     }
@@ -3048,7 +3051,7 @@
     if (!audio_is_valid_format(mFormat)) {
         LOG_ALWAYS_FATAL("HAL format %#x not valid for output", mFormat);
     }
-    if (hasMixer() && !isValidPcmSinkFormat(mFormat)) {
+    if (hasMixer() && !AudioFlinger::isValidPcmSinkFormat(mFormat)) {
         LOG_FATAL("HAL format %#x not supported for mixed output",
                 mFormat);
     }
@@ -3216,7 +3219,7 @@
     item.record();
 }
 
-AudioFlinger::ThreadBase::MetadataUpdate AudioFlinger::PlaybackThread::updateMetadata_l()
+ThreadBase::MetadataUpdate PlaybackThread::updateMetadata_l()
 {
     if (!isStreamInitialized() || !mActiveTracks.readAndClearHasChanged()) {
         return {}; // nothing to do
@@ -3233,13 +3236,14 @@
     return change;
 }
 
-void AudioFlinger::PlaybackThread::sendMetadataToBackend_l(
+void PlaybackThread::sendMetadataToBackend_l(
         const StreamOutHalInterface::SourceMetadata& metadata)
 {
     mOutput->stream->updateSourceMetadata(metadata);
 };
 
-status_t AudioFlinger::PlaybackThread::getRenderPosition(uint32_t *halFrames, uint32_t *dspFrames)
+status_t PlaybackThread::getRenderPosition(
+        uint32_t* halFrames, uint32_t* dspFrames) const
 {
     if (halFrames == NULL || dspFrames == NULL) {
         return BAD_VALUE;
@@ -3266,7 +3270,7 @@
     }
 }
 
-product_strategy_t AudioFlinger::PlaybackThread::getStrategyForSession_l(audio_session_t sessionId)
+product_strategy_t PlaybackThread::getStrategyForSession_l(audio_session_t sessionId) const
 {
     // session AUDIO_SESSION_OUTPUT_MIX is placed in same strategy as MUSIC stream so that
     // it is moved to correct output by audio policy manager when A2DP is connected or disconnected
@@ -3283,13 +3287,13 @@
 }
 
 
-AudioStreamOut* AudioFlinger::PlaybackThread::getOutput() const
+AudioStreamOut* PlaybackThread::getOutput() const
 {
     Mutex::Autolock _l(mLock);
     return mOutput;
 }
 
-AudioStreamOut* AudioFlinger::PlaybackThread::clearOutput()
+AudioStreamOut* PlaybackThread::clearOutput()
 {
     Mutex::Autolock _l(mLock);
     AudioStreamOut *output = mOutput;
@@ -3303,7 +3307,7 @@
 }
 
 // this method must always be called either with ThreadBase mLock held or inside the thread loop
-sp<StreamHalInterface> AudioFlinger::PlaybackThread::stream() const
+sp<StreamHalInterface> PlaybackThread::stream() const
 {
     if (mOutput == NULL) {
         return NULL;
@@ -3311,12 +3315,12 @@
     return mOutput->stream;
 }
 
-uint32_t AudioFlinger::PlaybackThread::activeSleepTimeUs() const
+uint32_t PlaybackThread::activeSleepTimeUs() const
 {
     return (uint32_t)((uint32_t)((mNormalFrameCount * 1000) / mSampleRate) * 1000);
 }
 
-status_t AudioFlinger::PlaybackThread::setSyncEvent(const sp<audioflinger::SyncEvent>& event)
+status_t PlaybackThread::setSyncEvent(const sp<SyncEvent>& event)
 {
     if (!isValidSyncEvent(event)) {
         return BAD_VALUE;
@@ -3335,13 +3339,12 @@
     return NAME_NOT_FOUND;
 }
 
-bool AudioFlinger::PlaybackThread::isValidSyncEvent(
-        const sp<audioflinger::SyncEvent>& event) const
+bool PlaybackThread::isValidSyncEvent(const sp<SyncEvent>& event) const
 {
     return event->type() == AudioSystem::SYNC_EVENT_PRESENTATION_COMPLETE;
 }
 
-void AudioFlinger::PlaybackThread::threadLoop_removeTracks(
+void PlaybackThread::threadLoop_removeTracks(
         [[maybe_unused]] const Vector<sp<IAfTrack>>& tracksToRemove)
 {
     // Miscellaneous track cleanup when removed from the active list,
@@ -3356,7 +3359,7 @@
 #endif
 }
 
-void AudioFlinger::PlaybackThread::checkSilentMode_l()
+void PlaybackThread::checkSilentMode_l()
 {
     if (!mMasterMute) {
         char value[PROPERTY_VALUE_MAX];
@@ -3382,7 +3385,7 @@
 }
 
 // shared by MIXER and DIRECT, overridden by DUPLICATING
-ssize_t AudioFlinger::PlaybackThread::threadLoop_write()
+ssize_t PlaybackThread::threadLoop_write()
 {
     LOG_HIST_TS();
     mInWrite = true;
@@ -3454,7 +3457,7 @@
 }
 
 // startMelComputation_l() must be called with AudioFlinger::mLock held
-void AudioFlinger::PlaybackThread::startMelComputation_l(
+void PlaybackThread::startMelComputation_l(
         const sp<audio_utils::MelProcessor>& processor)
 {
     auto outputSink = static_cast<AudioStreamOutSink*>(mOutputSink.get());
@@ -3464,7 +3467,7 @@
 }
 
 // stopMelComputation_l() must be called with AudioFlinger::mLock held
-void AudioFlinger::PlaybackThread::stopMelComputation_l()
+void PlaybackThread::stopMelComputation_l()
 {
     auto outputSink = static_cast<AudioStreamOutSink*>(mOutputSink.get());
     if (outputSink != nullptr) {
@@ -3472,7 +3475,7 @@
     }
 }
 
-void AudioFlinger::PlaybackThread::threadLoop_drain()
+void PlaybackThread::threadLoop_drain()
 {
     bool supportsDrain = false;
     if (mOutput->stream->supportsDrain(&supportsDrain) == OK && supportsDrain) {
@@ -3488,7 +3491,7 @@
     }
 }
 
-void AudioFlinger::PlaybackThread::threadLoop_exit()
+void PlaybackThread::threadLoop_exit()
 {
     {
         Mutex::Autolock _l(mLock);
@@ -3524,7 +3527,7 @@
  - idle sleep time
 */
 
-void AudioFlinger::PlaybackThread::cacheParameters_l()
+void PlaybackThread::cacheParameters_l()
 {
     mSinkBufferSize = mNormalFrameCount * mFrameSize;
     mActiveSleepTimeUs = activeSleepTimeUs();
@@ -3541,7 +3544,7 @@
     }
 }
 
-bool AudioFlinger::PlaybackThread::invalidateTracks_l(audio_stream_type_t streamType)
+bool PlaybackThread::invalidateTracks_l(audio_stream_type_t streamType)
 {
     ALOGV("MixerThread::invalidateTracks() mixer %p, streamType %d, mTracks.size %zu",
             this,  streamType, mTracks.size());
@@ -3557,18 +3560,18 @@
     return trackMatch;
 }
 
-void AudioFlinger::PlaybackThread::invalidateTracks(audio_stream_type_t streamType)
+void PlaybackThread::invalidateTracks(audio_stream_type_t streamType)
 {
     Mutex::Autolock _l(mLock);
     invalidateTracks_l(streamType);
 }
 
-void AudioFlinger::PlaybackThread::invalidateTracks(std::set<audio_port_handle_t>& portIds) {
+void PlaybackThread::invalidateTracks(std::set<audio_port_handle_t>& portIds) {
     Mutex::Autolock _l(mLock);
     invalidateTracks_l(portIds);
 }
 
-bool AudioFlinger::PlaybackThread::invalidateTracks_l(std::set<audio_port_handle_t>& portIds) {
+bool PlaybackThread::invalidateTracks_l(std::set<audio_port_handle_t>& portIds) {
     bool trackMatch = false;
     const size_t size = mTracks.size();
     for (size_t i = 0; i < size; i++) {
@@ -3586,7 +3589,7 @@
 }
 
 // getTrackById_l must be called with holding thread lock
-IAfTrack* AudioFlinger::PlaybackThread::getTrackById_l(
+IAfTrack* PlaybackThread::getTrackById_l(
         audio_port_handle_t trackPortId) {
     for (size_t i = 0; i < mTracks.size(); i++) {
         if (mTracks[i]->portId() == trackPortId) {
@@ -3596,7 +3599,7 @@
     return nullptr;
 }
 
-status_t AudioFlinger::PlaybackThread::addEffectChain_l(const sp<IAfEffectChain>& chain)
+status_t PlaybackThread::addEffectChain_l(const sp<IAfEffectChain>& chain)
 {
     audio_session_t session = chain->sessionId();
     sp<EffectBufferHalInterface> halInBuffer, halOutBuffer;
@@ -3732,7 +3735,7 @@
     return NO_ERROR;
 }
 
-size_t AudioFlinger::PlaybackThread::removeEffectChain_l(const sp<IAfEffectChain>& chain)
+size_t PlaybackThread::removeEffectChain_l(const sp<IAfEffectChain>& chain)
 {
     audio_session_t session = chain->sessionId();
 
@@ -3764,14 +3767,14 @@
     return mEffectChains.size();
 }
 
-status_t AudioFlinger::PlaybackThread::attachAuxEffect(
+status_t PlaybackThread::attachAuxEffect(
         const sp<IAfTrack>& track, int EffectId)
 {
     Mutex::Autolock _l(mLock);
     return attachAuxEffect_l(track, EffectId);
 }
 
-status_t AudioFlinger::PlaybackThread::attachAuxEffect_l(
+status_t PlaybackThread::attachAuxEffect_l(
         const sp<IAfTrack>& track, int EffectId)
 {
     status_t status = NO_ERROR;
@@ -3794,7 +3797,7 @@
     return status;
 }
 
-void AudioFlinger::PlaybackThread::detachAuxEffect_l(int effectId)
+void PlaybackThread::detachAuxEffect_l(int effectId)
 {
     for (size_t i = 0; i < mTracks.size(); ++i) {
         sp<IAfTrack> track = mTracks[i];
@@ -3804,7 +3807,7 @@
     }
 }
 
-bool AudioFlinger::PlaybackThread::threadLoop()
+bool PlaybackThread::threadLoop()
 NO_THREAD_SAFETY_ANALYSIS  // manual locking of AudioFlinger
 {
     aflog::setThreadWriter(mNBLogWriter.get());
@@ -3873,11 +3876,12 @@
             // Here, we try for the AF lock, but do not block on it as the latency
             // is more informational.
             if (mAudioFlinger->mLock.tryLock() == NO_ERROR) {
-                std::vector<PatchPanel::SoftwarePatch> swPatches;
+                std::vector<SoftwarePatch> swPatches;
                 double latencyMs = 0.; // not required; initialized for clang-tidy
                 status_t status = INVALID_OPERATION;
                 audio_patch_handle_t downstreamPatchHandle = AUDIO_PATCH_HANDLE_NONE;
-                if (mAudioFlinger->mPatchPanel.getDownstreamSoftwarePatches(id(), &swPatches) == OK
+                if (mAudioFlinger->mPatchPanel->getDownstreamSoftwarePatches(
+                                id(), &swPatches) == OK
                         && swPatches.size() > 0) {
                         status = swPatches[0].getLatencyMs_l(&latencyMs);
                         downstreamPatchHandle = swPatches[0].getPatchHandle();
@@ -4460,7 +4464,7 @@
     return false;
 }
 
-void AudioFlinger::PlaybackThread::collectTimestamps_l()
+void PlaybackThread::collectTimestamps_l()
 {
     if (mStandby) {
         mTimestampVerifier.discontinuity(discontinuityForStandbyOrFlush());
@@ -4596,7 +4600,7 @@
 }
 
 // removeTracks_l() must be called with ThreadBase::mLock held
-void AudioFlinger::PlaybackThread::removeTracks_l(const Vector<sp<IAfTrack>>& tracksToRemove)
+void PlaybackThread::removeTracks_l(const Vector<sp<IAfTrack>>& tracksToRemove)
 NO_THREAD_SAFETY_ANALYSIS  // release and re-acquire mLock
 {
     for (const auto& track : tracksToRemove) {
@@ -4638,7 +4642,7 @@
     }
 }
 
-status_t AudioFlinger::PlaybackThread::getTimestamp_l(AudioTimestamp& timestamp)
+status_t PlaybackThread::getTimestamp_l(AudioTimestamp& timestamp)
 {
     if (mNormalSink != 0) {
         ExtendedTimestamp ets;
@@ -4667,7 +4671,7 @@
 // All tracks attached to a mixer with flag VOIP_RX are tied to the same
 // stream type STREAM_VOICE_CALL so this will only change the HAL volume once even
 // if more than one track are active
-status_t AudioFlinger::PlaybackThread::handleVoipVolume_l(float *volume)
+status_t PlaybackThread::handleVoipVolume_l(float* volume)
 {
     status_t result = NO_ERROR;
     if ((mOutput->flags & AUDIO_OUTPUT_FLAG_VOIP_RX) != 0) {
@@ -4689,7 +4693,7 @@
     return result;
 }
 
-status_t AudioFlinger::MixerThread::createAudioPatch_l(const struct audio_patch *patch,
+status_t MixerThread::createAudioPatch_l(const struct audio_patch* patch,
                                                           audio_patch_handle_t *handle)
 {
     status_t status;
@@ -4706,7 +4710,7 @@
     return status;
 }
 
-status_t AudioFlinger::PlaybackThread::createAudioPatch_l(const struct audio_patch *patch,
+status_t PlaybackThread::createAudioPatch_l(const struct audio_patch *patch,
                                                           audio_patch_handle_t *handle)
 {
     status_t status = NO_ERROR;
@@ -4790,7 +4794,7 @@
     return status;
 }
 
-status_t AudioFlinger::MixerThread::releaseAudioPatch_l(const audio_patch_handle_t handle)
+status_t MixerThread::releaseAudioPatch_l(const audio_patch_handle_t handle)
 {
     status_t status;
     if (property_get_bool("af.patch_park", false /* default_value */)) {
@@ -4804,7 +4808,7 @@
     return status;
 }
 
-status_t AudioFlinger::PlaybackThread::releaseAudioPatch_l(const audio_patch_handle_t handle)
+status_t PlaybackThread::releaseAudioPatch_l(const audio_patch_handle_t handle)
 {
     status_t status = NO_ERROR;
 
@@ -4823,19 +4827,19 @@
     return status;
 }
 
-void AudioFlinger::PlaybackThread::addPatchTrack(const sp<IAfPatchTrack>& track)
+void PlaybackThread::addPatchTrack(const sp<IAfPatchTrack>& track)
 {
     Mutex::Autolock _l(mLock);
     mTracks.add(track);
 }
 
-void AudioFlinger::PlaybackThread::deletePatchTrack(const sp<IAfPatchTrack>& track)
+void PlaybackThread::deletePatchTrack(const sp<IAfPatchTrack>& track)
 {
     Mutex::Autolock _l(mLock);
     destroyTrack_l(track);
 }
 
-void AudioFlinger::PlaybackThread::toAudioPortConfig(struct audio_port_config *config)
+void PlaybackThread::toAudioPortConfig(struct audio_port_config* config)
 {
     ThreadBase::toAudioPortConfig(config);
     config->role = AUDIO_PORT_ROLE_SOURCE;
@@ -4849,7 +4853,14 @@
 
 // ----------------------------------------------------------------------------
 
-AudioFlinger::MixerThread::MixerThread(const sp<AudioFlinger>& audioFlinger, AudioStreamOut* output,
+/* static */
+sp<IAfPlaybackThread> IAfPlaybackThread::createMixerThread(
+        const sp<AudioFlinger>& audioFlinger, AudioStreamOut* output,
+        audio_io_handle_t id, bool systemReady, type_t type, audio_config_base_t* mixerConfig) {
+    return sp<MixerThread>::make(audioFlinger, output, id, systemReady, type, mixerConfig);
+}
+
+MixerThread::MixerThread(const sp<AudioFlinger>& audioFlinger, AudioStreamOut* output,
         audio_io_handle_t id, bool systemReady, type_t type, audio_config_base_t *mixerConfig)
     :   PlaybackThread(audioFlinger, output, id, type, systemReady, mixerConfig),
         // mAudioMixer below
@@ -5034,7 +5045,7 @@
     }
 }
 
-AudioFlinger::MixerThread::~MixerThread()
+MixerThread::~MixerThread()
 {
     if (mFastMixer != 0) {
         FastMixerStateQueue *sq = mFastMixer->sq();
@@ -5071,7 +5082,7 @@
     delete mAudioMixer;
 }
 
-void AudioFlinger::MixerThread::onFirstRef() {
+void MixerThread::onFirstRef() {
     PlaybackThread::onFirstRef();
 
     Mutex::Autolock _l(mLock);
@@ -5087,7 +5098,7 @@
     }
 }
 
-uint32_t AudioFlinger::MixerThread::correctLatency_l(uint32_t latency) const
+uint32_t MixerThread::correctLatency_l(uint32_t latency) const
 {
     if (mFastMixer != 0) {
         MonoPipe *pipe = (MonoPipe *)mPipeSink.get();
@@ -5096,7 +5107,7 @@
     return latency;
 }
 
-ssize_t AudioFlinger::MixerThread::threadLoop_write()
+ssize_t MixerThread::threadLoop_write()
 {
     // FIXME we should only do one push per cycle; confirm this is true
     // Start the fast mixer if it's not already running
@@ -5139,7 +5150,7 @@
     return PlaybackThread::threadLoop_write();
 }
 
-void AudioFlinger::MixerThread::threadLoop_standby()
+void MixerThread::threadLoop_standby()
 {
     // Idle the fast mixer if it's currently running
     if (mFastMixer != 0) {
@@ -5177,24 +5188,24 @@
     PlaybackThread::threadLoop_standby();
 }
 
-bool AudioFlinger::PlaybackThread::waitingAsyncCallback_l()
+bool PlaybackThread::waitingAsyncCallback_l()
 {
     return false;
 }
 
-bool AudioFlinger::PlaybackThread::shouldStandby_l()
+bool PlaybackThread::shouldStandby_l()
 {
     return !mStandby;
 }
 
-bool AudioFlinger::PlaybackThread::waitingAsyncCallback()
+bool PlaybackThread::waitingAsyncCallback()
 {
     Mutex::Autolock _l(mLock);
     return waitingAsyncCallback_l();
 }
 
 // shared by MIXER and DIRECT, overridden by DUPLICATING
-void AudioFlinger::PlaybackThread::threadLoop_standby()
+void PlaybackThread::threadLoop_standby()
 {
     ALOGV("Audio hardware entering standby, mixer %p, suspend count %d", this, mSuspended);
     mOutput->standby();
@@ -5210,20 +5221,20 @@
     setHalLatencyMode_l();
 }
 
-void AudioFlinger::PlaybackThread::onAddNewTrack_l()
+void PlaybackThread::onAddNewTrack_l()
 {
     ALOGV("signal playback thread");
     broadcast_l();
 }
 
-void AudioFlinger::PlaybackThread::onAsyncError()
+void PlaybackThread::onAsyncError()
 {
     for (int i = AUDIO_STREAM_SYSTEM; i < (int)AUDIO_STREAM_CNT; i++) {
         invalidateTracks((audio_stream_type_t)i);
     }
 }
 
-void AudioFlinger::MixerThread::threadLoop_mix()
+void MixerThread::threadLoop_mix()
 {
     // mix buffers...
     mAudioMixer->process();
@@ -5241,7 +5252,7 @@
 
 }
 
-void AudioFlinger::MixerThread::threadLoop_sleepTime()
+void MixerThread::threadLoop_sleepTime()
 {
     // If no tracks are ready, sleep once for the duration of an output
     // buffer size, then write 0s to the output
@@ -5295,7 +5306,7 @@
 }
 
 // prepareTracks_l() must be called with ThreadBase::mLock held
-AudioFlinger::PlaybackThread::mixer_state AudioFlinger::MixerThread::prepareTracks_l(
+PlaybackThread::mixer_state MixerThread::prepareTracks_l(
         Vector<sp<IAfTrack>>* tracksToRemove)
 {
     // clean up deleted track ids in AudioMixer before allocating new tracks
@@ -6091,7 +6102,7 @@
 }
 
 // trackCountForUid_l() must be called with ThreadBase::mLock held
-uint32_t AudioFlinger::PlaybackThread::trackCountForUid_l(uid_t uid) const
+uint32_t PlaybackThread::trackCountForUid_l(uid_t uid) const
 {
     uint32_t trackCount = 0;
     for (size_t i = 0; i < mTracks.size() ; i++) {
@@ -6102,7 +6113,7 @@
     return trackCount;
 }
 
-bool AudioFlinger::PlaybackThread::IsTimestampAdvancing::check(AudioStreamOut * output)
+bool PlaybackThread::IsTimestampAdvancing::check(AudioStreamOut* output)
 {
     // Check the timestamp to see if it's advancing once every 150ms. If we check too frequently, we
     // could falsely detect that the frame position has stalled due to underrun because we haven't
@@ -6126,7 +6137,7 @@
     return mLatchedValue;
 }
 
-void AudioFlinger::PlaybackThread::IsTimestampAdvancing::clear()
+void PlaybackThread::IsTimestampAdvancing::clear()
 {
     mLatchedValue = true;
     mPreviousPosition = 0;
@@ -6134,7 +6145,7 @@
 }
 
 // isTrackAllowed_l() must be called with ThreadBase::mLock held
-bool AudioFlinger::MixerThread::isTrackAllowed_l(
+bool MixerThread::isTrackAllowed_l(
         audio_channel_mask_t channelMask, audio_format_t format,
         audio_session_t sessionId, uid_t uid) const
 {
@@ -6154,7 +6165,7 @@
 }
 
 // checkForNewParameter_l() must be called with ThreadBase::mLock held
-bool AudioFlinger::MixerThread::checkForNewParameter_l(const String8& keyValuePair,
+bool MixerThread::checkForNewParameter_l(const String8& keyValuePair,
                                                        status_t& status)
 {
     bool reconfig = false;
@@ -6168,7 +6179,7 @@
         reconfig = true;
     }
     if (param.getInt(String8(AudioParameter::keyFormat), value) == NO_ERROR) {
-        if (!isValidPcmSinkFormat((audio_format_t) value)) {
+        if (!AudioFlinger::isValidPcmSinkFormat(static_cast<audio_format_t>(value))) {
             status = BAD_VALUE;
         } else {
             // no need to save value, since it's constant
@@ -6176,7 +6187,7 @@
         }
     }
     if (param.getInt(String8(AudioParameter::keyChannels), value) == NO_ERROR) {
-        if (!isValidPcmSinkChannelMask((audio_channel_mask_t) value)) {
+        if (!AudioFlinger::isValidPcmSinkChannelMask(static_cast<audio_channel_mask_t>(value))) {
             status = BAD_VALUE;
         } else {
             // no need to save value, since it's constant
@@ -6234,7 +6245,7 @@
 }
 
 
-void AudioFlinger::MixerThread::dumpInternals_l(int fd, const Vector<String16>& args)
+void MixerThread::dumpInternals_l(int fd, const Vector<String16>& args)
 {
     PlaybackThread::dumpInternals_l(fd, args);
     dprintf(fd, "  Thread throttle time (msecs): %u\n", mThreadThrottleTimeMs);
@@ -6281,17 +6292,17 @@
      dprintf(fd, "Supported latency modes: %s\n", toString(mSupportedLatencyModes).c_str());
 }
 
-uint32_t AudioFlinger::MixerThread::idleSleepTimeUs() const
+uint32_t MixerThread::idleSleepTimeUs() const
 {
     return (uint32_t)(((mNormalFrameCount * 1000) / mSampleRate) * 1000) / 2;
 }
 
-uint32_t AudioFlinger::MixerThread::suspendSleepTimeUs() const
+uint32_t MixerThread::suspendSleepTimeUs() const
 {
     return (uint32_t)(((mNormalFrameCount * 1000) / mSampleRate) * 1000);
 }
 
-void AudioFlinger::MixerThread::cacheParameters_l()
+void MixerThread::cacheParameters_l()
 {
     PlaybackThread::cacheParameters_l();
 
@@ -6302,11 +6313,11 @@
     maxPeriod = seconds(mNormalFrameCount) / mSampleRate * 15;
 }
 
-void AudioFlinger::MixerThread::onHalLatencyModesChanged_l() {
+void MixerThread::onHalLatencyModesChanged_l() {
     mAudioFlinger->onSupportedLatencyModesChanged(mId, mSupportedLatencyModes);
 }
 
-void AudioFlinger::MixerThread::setHalLatencyMode_l() {
+void MixerThread::setHalLatencyMode_l() {
     // Only handle latency mode if:
     // - mBluetoothLatencyModesEnabled is true
     // - the HAL supports latency modes
@@ -6348,7 +6359,7 @@
     }
 }
 
-void AudioFlinger::MixerThread::updateHalSupportedLatencyModes_l() {
+void MixerThread::updateHalSupportedLatencyModes_l() {
 
     if (mOutput == nullptr || mOutput->stream == nullptr) {
         return;
@@ -6366,7 +6377,7 @@
     }
 }
 
-status_t AudioFlinger::MixerThread::getSupportedLatencyModes(
+status_t MixerThread::getSupportedLatencyModes(
         std::vector<audio_latency_mode_t>* modes) {
     if (modes == nullptr) {
         return BAD_VALUE;
@@ -6376,7 +6387,7 @@
     return NO_ERROR;
 }
 
-void AudioFlinger::MixerThread::onRecommendedLatencyModeChanged(
+void MixerThread::onRecommendedLatencyModeChanged(
         std::vector<audio_latency_mode_t> modes) {
     Mutex::Autolock _l(mLock);
     if (modes != mSupportedLatencyModes) {
@@ -6387,7 +6398,7 @@
     }
 }
 
-status_t AudioFlinger::MixerThread::setBluetoothVariableLatencyEnabled(bool enabled) {
+status_t MixerThread::setBluetoothVariableLatencyEnabled(bool enabled) {
     if (mOutput == nullptr || mOutput->audioHwDev == nullptr
             || !mOutput->audioHwDev->supportsBluetoothVariableLatency()) {
         return INVALID_OPERATION;
@@ -6398,7 +6409,16 @@
 
 // ----------------------------------------------------------------------------
 
-AudioFlinger::DirectOutputThread::DirectOutputThread(const sp<AudioFlinger>& audioFlinger,
+/* static */
+sp<IAfPlaybackThread> IAfPlaybackThread::createDirectOutputThread(
+        const sp<AudioFlinger>& audioFlinger,
+        AudioStreamOut* output, audio_io_handle_t id, bool systemReady,
+        const audio_offload_info_t& offloadInfo) {
+    return sp<DirectOutputThread>::make(
+            audioFlinger, output, id, systemReady, offloadInfo);
+}
+
+DirectOutputThread::DirectOutputThread(const sp<AudioFlinger>& audioFlinger,
         AudioStreamOut* output, audio_io_handle_t id, ThreadBase::type_t type, bool systemReady,
         const audio_offload_info_t& offloadInfo)
     :   PlaybackThread(audioFlinger, output, id, type, systemReady)
@@ -6407,18 +6427,18 @@
     setMasterBalance(audioFlinger->getMasterBalance_l());
 }
 
-AudioFlinger::DirectOutputThread::~DirectOutputThread()
+DirectOutputThread::~DirectOutputThread()
 {
 }
 
-void AudioFlinger::DirectOutputThread::dumpInternals_l(int fd, const Vector<String16>& args)
+void DirectOutputThread::dumpInternals_l(int fd, const Vector<String16>& args)
 {
     PlaybackThread::dumpInternals_l(fd, args);
     dprintf(fd, "  Master balance: %f  Left: %f  Right: %f\n",
             mMasterBalance.load(), mMasterBalanceLeft, mMasterBalanceRight);
 }
 
-void AudioFlinger::DirectOutputThread::setMasterBalance(float balance)
+void DirectOutputThread::setMasterBalance(float balance)
 {
     Mutex::Autolock _l(mLock);
     if (mMasterBalance != balance) {
@@ -6428,7 +6448,7 @@
     }
 }
 
-void AudioFlinger::DirectOutputThread::processVolume_l(IAfTrack *track, bool lastTrack)
+void DirectOutputThread::processVolume_l(IAfTrack* track, bool lastTrack)
 {
     float left, right;
 
@@ -6507,7 +6527,7 @@
     }
 }
 
-void AudioFlinger::DirectOutputThread::onAddNewTrack_l()
+void DirectOutputThread::onAddNewTrack_l()
 {
     sp<IAfTrack> previousTrack = mPreviousTrack.promote();
     sp<IAfTrack> latestTrack = mActiveTracks.getLatest();
@@ -6532,7 +6552,7 @@
     PlaybackThread::onAddNewTrack_l();
 }
 
-AudioFlinger::PlaybackThread::mixer_state AudioFlinger::DirectOutputThread::prepareTracks_l(
+PlaybackThread::mixer_state DirectOutputThread::prepareTracks_l(
     Vector<sp<IAfTrack>>* tracksToRemove
 )
 {
@@ -6755,7 +6775,7 @@
     return mixerStatus;
 }
 
-void AudioFlinger::DirectOutputThread::threadLoop_mix()
+void DirectOutputThread::threadLoop_mix()
 {
     size_t frameCount = mFrameCount;
     int8_t *curBuf = (int8_t *)mSinkBuffer;
@@ -6782,7 +6802,7 @@
     mActiveTrack.clear();
 }
 
-void AudioFlinger::DirectOutputThread::threadLoop_sleepTime()
+void DirectOutputThread::threadLoop_sleepTime()
 {
     // do not write to HAL when paused
     if (mHwPaused || (usesHwAvSync() && mStandby)) {
@@ -6798,7 +6818,7 @@
     // linear or proportional PCM direct tracks in underrun.
 }
 
-void AudioFlinger::DirectOutputThread::threadLoop_exit()
+void DirectOutputThread::threadLoop_exit()
 {
     {
         Mutex::Autolock _l(mLock);
@@ -6816,7 +6836,7 @@
 }
 
 // must be called with thread mutex locked
-bool AudioFlinger::DirectOutputThread::shouldStandby_l()
+bool DirectOutputThread::shouldStandby_l()
 {
     bool trackPaused = false;
     bool trackStopped = false;
@@ -6833,7 +6853,7 @@
 }
 
 // checkForNewParameter_l() must be called with ThreadBase::mLock held
-bool AudioFlinger::DirectOutputThread::checkForNewParameter_l(const String8& keyValuePair,
+bool DirectOutputThread::checkForNewParameter_l(const String8& keyValuePair,
                                                               status_t& status)
 {
     bool reconfig = false;
@@ -6875,7 +6895,7 @@
     return reconfig;
 }
 
-uint32_t AudioFlinger::DirectOutputThread::activeSleepTimeUs() const
+uint32_t DirectOutputThread::activeSleepTimeUs() const
 {
     uint32_t time;
     if (audio_has_proportional_frames(mFormat)) {
@@ -6886,7 +6906,7 @@
     return time;
 }
 
-uint32_t AudioFlinger::DirectOutputThread::idleSleepTimeUs() const
+uint32_t DirectOutputThread::idleSleepTimeUs() const
 {
     uint32_t time;
     if (audio_has_proportional_frames(mFormat)) {
@@ -6897,7 +6917,7 @@
     return time;
 }
 
-uint32_t AudioFlinger::DirectOutputThread::suspendSleepTimeUs() const
+uint32_t DirectOutputThread::suspendSleepTimeUs() const
 {
     uint32_t time;
     if (audio_has_proportional_frames(mFormat)) {
@@ -6908,7 +6928,7 @@
     return time;
 }
 
-void AudioFlinger::DirectOutputThread::cacheParameters_l()
+void DirectOutputThread::cacheParameters_l()
 {
     PlaybackThread::cacheParameters_l();
 
@@ -6924,7 +6944,7 @@
     }
 }
 
-void AudioFlinger::DirectOutputThread::flushHw_l()
+void DirectOutputThread::flushHw_l()
 {
     PlaybackThread::flushHw_l();
     mOutput->flush();
@@ -6935,7 +6955,7 @@
     mMonotonicFrameCounter.onFlush();
 }
 
-int64_t AudioFlinger::DirectOutputThread::computeWaitTimeNs_l() const {
+int64_t DirectOutputThread::computeWaitTimeNs_l() const {
     // If a VolumeShaper is active, we must wake up periodically to update volume.
     const int64_t NS_PER_MS = 1000000;
     return mVolumeShaperActive ?
@@ -6944,8 +6964,8 @@
 
 // ----------------------------------------------------------------------------
 
-AudioFlinger::AsyncCallbackThread::AsyncCallbackThread(
-        const wp<AudioFlinger::PlaybackThread>& playbackThread)
+AsyncCallbackThread::AsyncCallbackThread(
+        const wp<PlaybackThread>& playbackThread)
     :   Thread(false /*canCallJava*/),
         mPlaybackThread(playbackThread),
         mWriteAckSequence(0),
@@ -6954,16 +6974,12 @@
 {
 }
 
-AudioFlinger::AsyncCallbackThread::~AsyncCallbackThread()
-{
-}
-
-void AudioFlinger::AsyncCallbackThread::onFirstRef()
+void AsyncCallbackThread::onFirstRef()
 {
     run("Offload Cbk", ANDROID_PRIORITY_URGENT_AUDIO);
 }
 
-bool AudioFlinger::AsyncCallbackThread::threadLoop()
+bool AsyncCallbackThread::threadLoop()
 {
     while (!exitPending()) {
         uint32_t writeAckSequence;
@@ -6992,7 +7008,7 @@
             mAsyncError = false;
         }
         {
-            sp<AudioFlinger::PlaybackThread> playbackThread = mPlaybackThread.promote();
+            const sp<PlaybackThread> playbackThread = mPlaybackThread.promote();
             if (playbackThread != 0) {
                 if (writeAckSequence & 1) {
                     playbackThread->resetWriteBlocked(writeAckSequence >> 1);
@@ -7009,7 +7025,7 @@
     return false;
 }
 
-void AudioFlinger::AsyncCallbackThread::exit()
+void AsyncCallbackThread::exit()
 {
     ALOGV("AsyncCallbackThread::exit");
     Mutex::Autolock _l(mLock);
@@ -7017,14 +7033,14 @@
     mWaitWorkCV.broadcast();
 }
 
-void AudioFlinger::AsyncCallbackThread::setWriteBlocked(uint32_t sequence)
+void AsyncCallbackThread::setWriteBlocked(uint32_t sequence)
 {
     Mutex::Autolock _l(mLock);
     // bit 0 is cleared
     mWriteAckSequence = sequence << 1;
 }
 
-void AudioFlinger::AsyncCallbackThread::resetWriteBlocked()
+void AsyncCallbackThread::resetWriteBlocked()
 {
     Mutex::Autolock _l(mLock);
     // ignore unexpected callbacks
@@ -7034,14 +7050,14 @@
     }
 }
 
-void AudioFlinger::AsyncCallbackThread::setDraining(uint32_t sequence)
+void AsyncCallbackThread::setDraining(uint32_t sequence)
 {
     Mutex::Autolock _l(mLock);
     // bit 0 is cleared
     mDrainSequence = sequence << 1;
 }
 
-void AudioFlinger::AsyncCallbackThread::resetDraining()
+void AsyncCallbackThread::resetDraining()
 {
     Mutex::Autolock _l(mLock);
     // ignore unexpected callbacks
@@ -7051,7 +7067,7 @@
     }
 }
 
-void AudioFlinger::AsyncCallbackThread::setAsyncError()
+void AsyncCallbackThread::setAsyncError()
 {
     Mutex::Autolock _l(mLock);
     mAsyncError = true;
@@ -7060,7 +7076,16 @@
 
 
 // ----------------------------------------------------------------------------
-AudioFlinger::OffloadThread::OffloadThread(const sp<AudioFlinger>& audioFlinger,
+
+/* static */
+sp<IAfPlaybackThread> IAfPlaybackThread::createOffloadThread(
+        const sp<AudioFlinger>& audioFlinger,
+        AudioStreamOut* output, audio_io_handle_t id, bool systemReady,
+        const audio_offload_info_t& offloadInfo) {
+    return sp<OffloadThread>::make(audioFlinger, output, id, systemReady, offloadInfo);
+}
+
+OffloadThread::OffloadThread(const sp<AudioFlinger>& audioFlinger,
         AudioStreamOut* output, audio_io_handle_t id, bool systemReady,
         const audio_offload_info_t& offloadInfo)
     :   DirectOutputThread(audioFlinger, output, id, OFFLOAD, systemReady, offloadInfo),
@@ -7071,7 +7096,7 @@
     mKeepWakeLock = property_get_bool("ro.audio.offload_wakelock", true /* default_value */);
 }
 
-void AudioFlinger::OffloadThread::threadLoop_exit()
+void OffloadThread::threadLoop_exit()
 {
     if (mFlushPending || mHwPaused) {
         // If a flush is pending or track was paused, just discard buffered data
@@ -7087,7 +7112,7 @@
     PlaybackThread::threadLoop_exit();
 }
 
-AudioFlinger::PlaybackThread::mixer_state AudioFlinger::OffloadThread::prepareTracks_l(
+PlaybackThread::mixer_state OffloadThread::prepareTracks_l(
     Vector<sp<IAfTrack>>* tracksToRemove
 )
 {
@@ -7330,7 +7355,7 @@
 }
 
 // must be called with thread mutex locked
-bool AudioFlinger::OffloadThread::waitingAsyncCallback_l()
+bool OffloadThread::waitingAsyncCallback_l()
 {
     ALOGVV("waitingAsyncCallback_l mWriteAckSequence %d mDrainSequence %d",
           mWriteAckSequence, mDrainSequence);
@@ -7340,13 +7365,13 @@
     return false;
 }
 
-bool AudioFlinger::OffloadThread::waitingAsyncCallback()
+bool OffloadThread::waitingAsyncCallback()
 {
     Mutex::Autolock _l(mLock);
     return waitingAsyncCallback_l();
 }
 
-void AudioFlinger::OffloadThread::flushHw_l()
+void OffloadThread::flushHw_l()
 {
     DirectOutputThread::flushHw_l();
     // Flush anything still waiting in the mixbuffer
@@ -7367,7 +7392,7 @@
     }
 }
 
-void AudioFlinger::OffloadThread::invalidateTracks(audio_stream_type_t streamType)
+void OffloadThread::invalidateTracks(audio_stream_type_t streamType)
 {
     Mutex::Autolock _l(mLock);
     if (PlaybackThread::invalidateTracks_l(streamType)) {
@@ -7375,7 +7400,7 @@
     }
 }
 
-void AudioFlinger::OffloadThread::invalidateTracks(std::set<audio_port_handle_t>& portIds) {
+void OffloadThread::invalidateTracks(std::set<audio_port_handle_t>& portIds) {
     Mutex::Autolock _l(mLock);
     if (PlaybackThread::invalidateTracks_l(portIds)) {
         mFlushPending = true;
@@ -7384,8 +7409,15 @@
 
 // ----------------------------------------------------------------------------
 
-AudioFlinger::DuplicatingThread::DuplicatingThread(const sp<AudioFlinger>& audioFlinger,
-        AudioFlinger::MixerThread* mainThread, audio_io_handle_t id, bool systemReady)
+/* static */
+sp<IAfDuplicatingThread> IAfDuplicatingThread::create(
+        const sp<AudioFlinger>& audioFlinger,
+        IAfPlaybackThread* mainThread, audio_io_handle_t id, bool systemReady) {
+    return sp<DuplicatingThread>::make(audioFlinger, mainThread, id, systemReady);
+}
+
+DuplicatingThread::DuplicatingThread(const sp<AudioFlinger>& audioFlinger,
+       IAfPlaybackThread* mainThread, audio_io_handle_t id, bool systemReady)
     :   MixerThread(audioFlinger, mainThread->getOutput(), id,
                     systemReady, DUPLICATING),
         mWaitTimeMs(UINT_MAX)
@@ -7393,14 +7425,14 @@
     addOutputTrack(mainThread);
 }
 
-AudioFlinger::DuplicatingThread::~DuplicatingThread()
+DuplicatingThread::~DuplicatingThread()
 {
     for (size_t i = 0; i < mOutputTracks.size(); i++) {
         mOutputTracks[i]->destroy();
     }
 }
 
-void AudioFlinger::DuplicatingThread::threadLoop_mix()
+void DuplicatingThread::threadLoop_mix()
 {
     // mix buffers...
     if (outputsReady()) {
@@ -7418,7 +7450,7 @@
     mStandbyTimeNs = systemTime() + mStandbyDelayNs;
 }
 
-void AudioFlinger::DuplicatingThread::threadLoop_sleepTime()
+void DuplicatingThread::threadLoop_sleepTime()
 {
     if (mSleepTimeUs == 0) {
         if (mMixerStatus == MIXER_TRACKS_ENABLED) {
@@ -7438,7 +7470,7 @@
     }
 }
 
-ssize_t AudioFlinger::DuplicatingThread::threadLoop_write()
+ssize_t DuplicatingThread::threadLoop_write()
 {
     for (size_t i = 0; i < outputTracks.size(); i++) {
         const ssize_t actualWritten = outputTracks[i]->write(mSinkBuffer, writeFrames);
@@ -7466,7 +7498,7 @@
     return (ssize_t)mSinkBufferSize;
 }
 
-void AudioFlinger::DuplicatingThread::threadLoop_standby()
+void DuplicatingThread::threadLoop_standby()
 {
     // DuplicatingThread implements standby by stopping all tracks
     for (size_t i = 0; i < outputTracks.size(); i++) {
@@ -7474,7 +7506,7 @@
     }
 }
 
-void AudioFlinger::DuplicatingThread::dumpInternals_l(int fd, const Vector<String16>& args)
+void DuplicatingThread::dumpInternals_l(int fd, const Vector<String16>& args)
 {
     MixerThread::dumpInternals_l(fd, args);
 
@@ -7484,8 +7516,7 @@
     if (numTracks > 0) {
         ss << ":";
         for (const auto &track : mOutputTracks) {
-            // TODO(b/288339104) type
-            const auto thread = sp<ThreadBase>::cast(track->thread().promote());
+            const auto thread = track->thread().promote();
             ss << " (" << track->id() << " : ";
             if (thread.get() != nullptr) {
                 ss << thread.get() << ", " << thread->id();
@@ -7500,17 +7531,17 @@
     write(fd, result.c_str(), result.size());
 }
 
-void AudioFlinger::DuplicatingThread::saveOutputTracks()
+void DuplicatingThread::saveOutputTracks()
 {
     outputTracks = mOutputTracks;
 }
 
-void AudioFlinger::DuplicatingThread::clearOutputTracks()
+void DuplicatingThread::clearOutputTracks()
 {
     outputTracks.clear();
 }
 
-void AudioFlinger::DuplicatingThread::addOutputTrack(MixerThread *thread)
+void DuplicatingThread::addOutputTrack(IAfPlaybackThread* thread)
 {
     Mutex::Autolock _l(mLock);
     // The downstream MixerThread consumes thread->frameCount() amount of frames per mix pass.
@@ -7547,7 +7578,7 @@
     updateWaitTime_l();
 }
 
-void AudioFlinger::DuplicatingThread::removeOutputTrack(MixerThread *thread)
+void DuplicatingThread::removeOutputTrack(IAfPlaybackThread* thread)
 {
     Mutex::Autolock _l(mLock);
     for (size_t i = 0; i < mOutputTracks.size(); i++) {
@@ -7565,12 +7596,11 @@
 }
 
 // caller must hold mLock
-void AudioFlinger::DuplicatingThread::updateWaitTime_l()
+void DuplicatingThread::updateWaitTime_l()
 {
     mWaitTimeMs = UINT_MAX;
     for (size_t i = 0; i < mOutputTracks.size(); i++) {
-        // TODO(b/288339104) type
-        const auto strong = sp<ThreadBase>::cast(mOutputTracks[i]->thread().promote());
+        const auto strong = mOutputTracks[i]->thread().promote();
         if (strong != 0) {
             uint32_t waitTimeMs = (strong->frameCount() * 2 * 1000) / strong->sampleRate();
             if (waitTimeMs < mWaitTimeMs) {
@@ -7580,19 +7610,18 @@
     }
 }
 
-bool AudioFlinger::DuplicatingThread::outputsReady()
+bool DuplicatingThread::outputsReady()
 {
     for (size_t i = 0; i < outputTracks.size(); i++) {
-        // TODO(b/288339104) type
-        const auto thread = sp<ThreadBase>::cast(outputTracks[i]->thread().promote());
+        const auto thread = outputTracks[i]->thread().promote();
         if (thread == 0) {
             ALOGW("DuplicatingThread::outputsReady() could not promote thread on output track %p",
                     outputTracks[i].get());
             return false;
         }
-        PlaybackThread *playbackThread = (PlaybackThread *)thread.get();
+        IAfPlaybackThread* const playbackThread = thread->asIAfPlaybackThread().get();
         // see note at standby() declaration
-        if (playbackThread->standby() && !playbackThread->isSuspended()) {
+        if (playbackThread->inStandby() && !playbackThread->isSuspended()) {
             ALOGV("DuplicatingThread output track %p on thread %p Not Ready", outputTracks[i].get(),
                     thread.get());
             return false;
@@ -7601,7 +7630,7 @@
     return true;
 }
 
-void AudioFlinger::DuplicatingThread::sendMetadataToBackend_l(
+void DuplicatingThread::sendMetadataToBackend_l(
         const StreamOutHalInterface::SourceMetadata& metadata)
 {
     for (auto& outputTrack : outputTracks) { // not mOutputTracks
@@ -7609,12 +7638,12 @@
     }
 }
 
-uint32_t AudioFlinger::DuplicatingThread::activeSleepTimeUs() const
+uint32_t DuplicatingThread::activeSleepTimeUs() const
 {
     return (mWaitTimeMs * 1000) / 2;
 }
 
-void AudioFlinger::DuplicatingThread::cacheParameters_l()
+void DuplicatingThread::cacheParameters_l()
 {
     // updateWaitTime_l() sets mWaitTimeMs, which affects activeSleepTimeUs(), so call it first
     updateWaitTime_l();
@@ -7624,7 +7653,17 @@
 
 // ----------------------------------------------------------------------------
 
-AudioFlinger::SpatializerThread::SpatializerThread(const sp<AudioFlinger>& audioFlinger,
+/* static */
+sp<IAfPlaybackThread> IAfPlaybackThread::createSpatializerThread(
+        const sp<AudioFlinger>& audioFlinger,
+        AudioStreamOut* output,
+        audio_io_handle_t id,
+        bool systemReady,
+        audio_config_base_t* mixerConfig) {
+    return sp<SpatializerThread>::make(audioFlinger, output, id, systemReady, mixerConfig);
+}
+
+SpatializerThread::SpatializerThread(const sp<AudioFlinger>& audioFlinger,
                                                              AudioStreamOut* output,
                                                              audio_io_handle_t id,
                                                              bool systemReady,
@@ -7633,7 +7672,7 @@
 {
 }
 
-void AudioFlinger::SpatializerThread::onFirstRef() {
+void SpatializerThread::onFirstRef() {
     MixerThread::onFirstRef();
 
     const pid_t tid = getTid();
@@ -7648,7 +7687,7 @@
     }
 }
 
-void AudioFlinger::SpatializerThread::setHalLatencyMode_l() {
+void SpatializerThread::setHalLatencyMode_l() {
     // if mSupportedLatencyModes is empty, the HAL stream does not support
     // latency mode control and we can exit.
     if (mSupportedLatencyModes.empty()) {
@@ -7686,7 +7725,7 @@
     }
 }
 
-status_t AudioFlinger::SpatializerThread::setRequestedLatencyMode(audio_latency_mode_t mode) {
+status_t SpatializerThread::setRequestedLatencyMode(audio_latency_mode_t mode) {
     if (mode != AUDIO_LATENCY_MODE_LOW && mode != AUDIO_LATENCY_MODE_FREE) {
         return BAD_VALUE;
     }
@@ -7695,7 +7734,7 @@
     return NO_ERROR;
 }
 
-void AudioFlinger::SpatializerThread::checkOutputStageEffects()
+void SpatializerThread::checkOutputStageEffects()
 {
     bool hasVirtualizer = false;
     bool hasDownMixer = false;
@@ -7751,7 +7790,14 @@
 //      Record
 // ----------------------------------------------------------------------------
 
-AudioFlinger::RecordThread::RecordThread(const sp<AudioFlinger>& audioFlinger,
+sp<IAfRecordThread> IAfRecordThread::create(const sp<AudioFlinger>& audioFlinger,
+        AudioStreamIn* input,
+        audio_io_handle_t id,
+        bool systemReady) {
+    return sp<RecordThread>::make(audioFlinger, input, id, systemReady);
+}
+
+RecordThread::RecordThread(const sp<AudioFlinger>& audioFlinger,
                                          AudioStreamIn *input,
                                          audio_io_handle_t id,
                                          bool systemReady
@@ -7910,7 +7956,7 @@
     // FIXME mNormalSource
 }
 
-AudioFlinger::RecordThread::~RecordThread()
+RecordThread::~RecordThread()
 {
     if (mFastCapture != 0) {
         FastCaptureStateQueue *sq = mFastCapture->sq();
@@ -7932,12 +7978,12 @@
     free(mRsmpInBuffer);
 }
 
-void AudioFlinger::RecordThread::onFirstRef()
+void RecordThread::onFirstRef()
 {
     run(mThreadName, PRIORITY_URGENT_AUDIO);
 }
 
-void AudioFlinger::RecordThread::preExit()
+void RecordThread::preExit()
 {
     ALOGV("  preExit()");
     Mutex::Autolock _l(mLock);
@@ -7949,7 +7995,7 @@
     mStartStopCond.broadcast();
 }
 
-bool AudioFlinger::RecordThread::threadLoop()
+bool RecordThread::threadLoop()
 {
     nsecs_t lastWarning = 0;
 
@@ -8514,7 +8560,7 @@
     return false;
 }
 
-void AudioFlinger::RecordThread::standbyIfNotAlreadyInStandby()
+void RecordThread::standbyIfNotAlreadyInStandby()
 {
     if (!mStandby) {
         inputStandBy();
@@ -8524,7 +8570,7 @@
     }
 }
 
-void AudioFlinger::RecordThread::inputStandBy()
+void RecordThread::inputStandBy()
 {
     // Idle the fast capture if it's currently running
     if (mFastCapture != 0) {
@@ -8565,7 +8611,7 @@
 }
 
 // RecordThread::createRecordTrack_l() must be called with AudioFlinger::mLock held
-sp<IAfRecordTrack> AudioFlinger::RecordThread::createRecordTrack_l(
+sp<IAfRecordTrack> RecordThread::createRecordTrack_l(
         const sp<Client>& client,
         const audio_attributes_t& attr,
         uint32_t *pSampleRate,
@@ -8763,7 +8809,7 @@
     return track;
 }
 
-status_t AudioFlinger::RecordThread::start(IAfRecordTrack* recordTrack,
+status_t RecordThread::start(IAfRecordTrack* recordTrack,
                                            AudioSystem::sync_event_t event,
                                            audio_session_t triggerSession)
 {
@@ -8859,21 +8905,21 @@
     }
 }
 
-void AudioFlinger::RecordThread::syncStartEventCallback(const wp<audioflinger::SyncEvent>& event)
+void RecordThread::syncStartEventCallback(const wp<SyncEvent>& event)
 {
-    sp<audioflinger::SyncEvent> strongEvent = event.promote();
+    const sp<SyncEvent> strongEvent = event.promote();
 
     if (strongEvent != 0) {
         sp<IAfTrackBase> ptr =
                 std::any_cast<const wp<IAfTrackBase>>(strongEvent->cookie()).promote();
         if (ptr != nullptr) {
-            // TODO(b/288339104) handleSyncStartEvent is in IAfTrackBase not IAfRecordTrack.
+            // TODO(b/291317898) handleSyncStartEvent is in IAfTrackBase not IAfRecordTrack.
             ptr->handleSyncStartEvent(strongEvent);
         }
     }
 }
 
-bool AudioFlinger::RecordThread::stop(IAfRecordTrack* recordTrack) {
+bool RecordThread::stop(IAfRecordTrack* recordTrack) {
     ALOGV("RecordThread::stop");
     AutoMutex _l(mLock);
     // if we're invalid, we can't be on the ActiveTracks.
@@ -8901,14 +8947,12 @@
     return false;
 }
 
-bool AudioFlinger::RecordThread::isValidSyncEvent(
-        const sp<audioflinger::SyncEvent>& /* event */) const
+bool RecordThread::isValidSyncEvent(const sp<SyncEvent>& /* event */) const
 {
     return false;
 }
 
-status_t AudioFlinger::RecordThread::setSyncEvent(
-        const sp<audioflinger::SyncEvent>& event __unused)
+status_t RecordThread::setSyncEvent(const sp<SyncEvent>& /* event */)
 {
 #if 0   // This branch is currently dead code, but is preserved in case it will be needed in future
     if (!isValidSyncEvent(event)) {
@@ -8933,8 +8977,8 @@
 #endif
 }
 
-status_t AudioFlinger::RecordThread::getActiveMicrophones(
-        std::vector<media::MicrophoneInfoFw>* activeMicrophones)
+status_t RecordThread::getActiveMicrophones(
+        std::vector<media::MicrophoneInfoFw>* activeMicrophones) const
 {
     ALOGV("RecordThread::getActiveMicrophones");
     AutoMutex _l(mLock);
@@ -8945,7 +8989,7 @@
     return status;
 }
 
-status_t AudioFlinger::RecordThread::setPreferredMicrophoneDirection(
+status_t RecordThread::setPreferredMicrophoneDirection(
             audio_microphone_direction_t direction)
 {
     ALOGV("setPreferredMicrophoneDirection(%d)", direction);
@@ -8956,7 +9000,7 @@
     return mInput->stream->setPreferredMicrophoneDirection(direction);
 }
 
-status_t AudioFlinger::RecordThread::setPreferredMicrophoneFieldDimension(float zoom)
+status_t RecordThread::setPreferredMicrophoneFieldDimension(float zoom)
 {
     ALOGV("setPreferredMicrophoneFieldDimension(%f)", zoom);
     AutoMutex _l(mLock);
@@ -8966,14 +9010,14 @@
     return mInput->stream->setPreferredMicrophoneFieldDimension(zoom);
 }
 
-status_t AudioFlinger::RecordThread::shareAudioHistory(
+status_t RecordThread::shareAudioHistory(
         const std::string& sharedAudioPackageName, audio_session_t sharedSessionId,
         int64_t sharedAudioStartMs) {
     AutoMutex _l(mLock);
     return shareAudioHistory_l(sharedAudioPackageName, sharedSessionId, sharedAudioStartMs);
 }
 
-status_t AudioFlinger::RecordThread::shareAudioHistory_l(
+status_t RecordThread::shareAudioHistory_l(
         const std::string& sharedAudioPackageName, audio_session_t sharedSessionId,
         int64_t sharedAudioStartMs) {
 
@@ -9013,13 +9057,13 @@
     return NO_ERROR;
 }
 
-void AudioFlinger::RecordThread::resetAudioHistory_l() {
+void RecordThread::resetAudioHistory_l() {
     mSharedAudioSessionId = AUDIO_SESSION_NONE;
     mSharedAudioStartFrames = -1;
     mSharedAudioPackageName = "";
 }
 
-AudioFlinger::ThreadBase::MetadataUpdate AudioFlinger::RecordThread::updateMetadata_l()
+ThreadBase::MetadataUpdate RecordThread::updateMetadata_l()
 {
     if (!isStreamInitialized() || !mActiveTracks.readAndClearHasChanged()) {
         return {}; // nothing to do
@@ -9036,7 +9080,7 @@
 }
 
 // destroyTrack_l() must be called with ThreadBase::mLock held
-void AudioFlinger::RecordThread::destroyTrack_l(const sp<IAfRecordTrack>& track)
+void RecordThread::destroyTrack_l(const sp<IAfRecordTrack>& track)
 {
     track->terminate();
     track->setState(IAfTrackBase::STOPPED);
@@ -9047,7 +9091,7 @@
     }
 }
 
-void AudioFlinger::RecordThread::removeTrack_l(const sp<IAfRecordTrack>& track)
+void RecordThread::removeTrack_l(const sp<IAfRecordTrack>& track)
 {
     String8 result;
     track->appendDump(result, false /* active */);
@@ -9061,7 +9105,7 @@
     }
 }
 
-void AudioFlinger::RecordThread::dumpInternals_l(int fd, const Vector<String16>& args __unused)
+void RecordThread::dumpInternals_l(int fd, const Vector<String16>& /* args */)
 {
     AudioStreamIn *input = mInput;
     audio_input_flags_t flags = input != NULL ? input->flags : AUDIO_INPUT_FLAG_NONE;
@@ -9089,7 +9133,7 @@
     copy->dump(fd);
 }
 
-void AudioFlinger::RecordThread::dumpTracks_l(int fd, const Vector<String16>& args __unused)
+void RecordThread::dumpTracks_l(int fd, const Vector<String16>& /* args */)
 {
     String8 result;
     size_t numtracks = mTracks.size();
@@ -9133,7 +9177,7 @@
     write(fd, result.string(), result.size());
 }
 
-void AudioFlinger::RecordThread::setRecordSilenced(audio_port_handle_t portId, bool silenced)
+void RecordThread::setRecordSilenced(audio_port_handle_t portId, bool silenced)
 {
     Mutex::Autolock _l(mLock);
     for (size_t i = 0; i < mTracks.size() ; i++) {
@@ -9146,8 +9190,8 @@
 
 void ResamplerBufferProvider::reset()
 {
-    const auto threadBase = sp<AudioFlinger::ThreadBase>::cast(mRecordTrack->thread().promote());
-    auto* const recordThread = static_cast<AudioFlinger::RecordThread *>(threadBase.get());
+    const auto threadBase = mRecordTrack->thread().promote();
+    auto* const recordThread = static_cast<RecordThread *>(threadBase->asIAfRecordThread().get());
     mRsmpInUnrel = 0;
     const int32_t rear = recordThread->mRsmpInRear;
     ssize_t deltaFrames = 0;
@@ -9170,8 +9214,8 @@
 void ResamplerBufferProvider::sync(
         size_t *framesAvailable, bool *hasOverrun)
 {
-    const auto threadBase = sp<AudioFlinger::ThreadBase>::cast(mRecordTrack->thread().promote());
-    auto* const recordThread = static_cast<AudioFlinger::RecordThread *>(threadBase.get());
+    const auto threadBase = mRecordTrack->thread().promote();
+    auto* const recordThread = static_cast<RecordThread *>(threadBase->asIAfRecordThread().get());
     const int32_t rear = recordThread->mRsmpInRear;
     const int32_t front = mRsmpInFront;
     const ssize_t filled = audio_utils::safe_sub_overflow(rear, front);
@@ -9204,13 +9248,13 @@
 status_t ResamplerBufferProvider::getNextBuffer(
         AudioBufferProvider::Buffer* buffer)
 {
-    const auto threadBase = sp<AudioFlinger::ThreadBase>::cast(mRecordTrack->thread().promote());
+    const auto threadBase = mRecordTrack->thread().promote();
     if (threadBase == 0) {
         buffer->frameCount = 0;
         buffer->raw = NULL;
         return NOT_ENOUGH_DATA;
     }
-    auto* const recordThread = static_cast<AudioFlinger::RecordThread *>(threadBase.get());
+    auto* const recordThread = static_cast<RecordThread *>(threadBase->asIAfRecordThread().get());
     int32_t rear = recordThread->mRsmpInRear;
     int32_t front = mRsmpInFront;
     ssize_t filled = audio_utils::safe_sub_overflow(rear, front);
@@ -9258,13 +9302,13 @@
     buffer->frameCount = 0;
 }
 
-void AudioFlinger::RecordThread::checkBtNrec()
+void RecordThread::checkBtNrec()
 {
     Mutex::Autolock _l(mLock);
     checkBtNrec_l();
 }
 
-void AudioFlinger::RecordThread::checkBtNrec_l()
+void RecordThread::checkBtNrec_l()
 {
     // disable AEC and NS if the device is a BT SCO headset supporting those
     // pre processings
@@ -9279,7 +9323,7 @@
 }
 
 
-bool AudioFlinger::RecordThread::checkForNewParameter_l(const String8& keyValuePair,
+bool RecordThread::checkForNewParameter_l(const String8& keyValuePair,
                                                         status_t& status)
 {
     bool reconfig = false;
@@ -9367,7 +9411,7 @@
     return reconfig;
 }
 
-String8 AudioFlinger::RecordThread::getParameters(const String8& keys)
+String8 RecordThread::getParameters(const String8& keys)
 {
     Mutex::Autolock _l(mLock);
     if (initCheck() == NO_ERROR) {
@@ -9379,7 +9423,7 @@
     return {};
 }
 
-void AudioFlinger::RecordThread::ioConfigChanged(audio_io_config_event_t event, pid_t pid,
+void RecordThread::ioConfigChanged(audio_io_config_event_t event, pid_t pid,
                                                  audio_port_handle_t portId) {
     sp<AudioIoDescriptor> desc;
     switch (event) {
@@ -9400,7 +9444,7 @@
     mAudioFlinger->ioConfigChanged(event, desc, pid);
 }
 
-void AudioFlinger::RecordThread::readInputParameters_l()
+void RecordThread::readInputParameters_l()
 {
     status_t result = mInput->stream->getAudioProperties(&mSampleRate, &mChannelMask, &mHALFormat);
     LOG_ALWAYS_FATAL_IF(result != OK, "Error retrieving audio properties from HAL: %d", result);
@@ -9443,7 +9487,7 @@
         .record();
 }
 
-uint32_t AudioFlinger::RecordThread::getInputFramesLost()
+uint32_t RecordThread::getInputFramesLost() const
 {
     Mutex::Autolock _l(mLock);
     uint32_t result;
@@ -9453,7 +9497,7 @@
     return 0;
 }
 
-KeyedVector<audio_session_t, bool> AudioFlinger::RecordThread::sessionIds() const
+KeyedVector<audio_session_t, bool> RecordThread::sessionIds() const
 {
     KeyedVector<audio_session_t, bool> ids;
     Mutex::Autolock _l(mLock);
@@ -9467,7 +9511,7 @@
     return ids;
 }
 
-AudioFlinger::AudioStreamIn* AudioFlinger::RecordThread::clearInput()
+AudioStreamIn* RecordThread::clearInput()
 {
     Mutex::Autolock _l(mLock);
     AudioStreamIn *input = mInput;
@@ -9476,7 +9520,7 @@
 }
 
 // this method must always be called either with ThreadBase mLock held or inside the thread loop
-sp<StreamHalInterface> AudioFlinger::RecordThread::stream() const
+sp<StreamHalInterface> RecordThread::stream() const
 {
     if (mInput == NULL) {
         return NULL;
@@ -9484,7 +9528,7 @@
     return mInput->stream;
 }
 
-status_t AudioFlinger::RecordThread::addEffectChain_l(const sp<IAfEffectChain>& chain)
+status_t RecordThread::addEffectChain_l(const sp<IAfEffectChain>& chain)
 {
     ALOGV("addEffectChain_l() %p on thread %p", chain.get(), this);
     chain->setThread(this);
@@ -9502,7 +9546,7 @@
     return NO_ERROR;
 }
 
-size_t AudioFlinger::RecordThread::removeEffectChain_l(const sp<IAfEffectChain>& chain)
+size_t RecordThread::removeEffectChain_l(const sp<IAfEffectChain>& chain)
 {
     ALOGV("removeEffectChain_l() %p from thread %p", chain.get(), this);
 
@@ -9515,7 +9559,7 @@
     return mEffectChains.size();
 }
 
-status_t AudioFlinger::RecordThread::createAudioPatch_l(const struct audio_patch *patch,
+status_t RecordThread::createAudioPatch_l(const struct audio_patch* patch,
                                                           audio_patch_handle_t *handle)
 {
     status_t status = NO_ERROR;
@@ -9572,7 +9616,7 @@
     return status;
 }
 
-status_t AudioFlinger::RecordThread::releaseAudioPatch_l(const audio_patch_handle_t handle)
+status_t RecordThread::releaseAudioPatch_l(const audio_patch_handle_t handle)
 {
     status_t status = NO_ERROR;
 
@@ -9591,7 +9635,7 @@
     return status;
 }
 
-void AudioFlinger::RecordThread::updateOutDevices(const DeviceDescriptorBaseVector& outDevices)
+void RecordThread::updateOutDevices(const DeviceDescriptorBaseVector& outDevices)
 {
     Mutex::Autolock _l(mLock);
     mOutDevices = outDevices;
@@ -9601,7 +9645,7 @@
     }
 }
 
-int32_t AudioFlinger::RecordThread::getOldestFront_l()
+int32_t RecordThread::getOldestFront_l()
 {
     if (mTracks.size() == 0) {
         return mRsmpInRear;
@@ -9623,7 +9667,7 @@
     return oldestFront;
 }
 
-void AudioFlinger::RecordThread::updateFronts_l(int32_t offset)
+void RecordThread::updateFronts_l(int32_t offset)
 {
     if (offset == 0) {
         return;
@@ -9635,7 +9679,7 @@
     }
 }
 
-void AudioFlinger::RecordThread::resizeInputBuffer_l(int32_t maxSharedAudioHistoryMs)
+void RecordThread::resizeInputBuffer_l(int32_t maxSharedAudioHistoryMs)
 {
     // This is the formula for calculating the temporary buffer size.
     // With 7 HAL buffers, we can guarantee ability to down-sample the input by ratio of 6:1 to
@@ -9659,7 +9703,7 @@
     mRsmpInRear = 0;
 
     ALOG_ASSERT(maxSharedAudioHistoryMs >= 0
-            && maxSharedAudioHistoryMs <= AudioFlinger::kMaxSharedAudioHistoryMs,
+            && maxSharedAudioHistoryMs <= kMaxSharedAudioHistoryMs,
             "resizeInputBuffer_l() called with invalid max shared history %d",
             maxSharedAudioHistoryMs);
     if (maxSharedAudioHistoryMs != 0) {
@@ -9728,7 +9772,7 @@
     mRsmpInBuffer = rsmpInBuffer;
 }
 
-void AudioFlinger::RecordThread::addPatchTrack(const sp<IAfPatchRecord>& record)
+void RecordThread::addPatchTrack(const sp<IAfPatchRecord>& record)
 {
     Mutex::Autolock _l(mLock);
     mTracks.add(record);
@@ -9737,7 +9781,7 @@
     }
 }
 
-void AudioFlinger::RecordThread::deletePatchTrack(const sp<IAfPatchRecord>& record)
+void RecordThread::deletePatchTrack(const sp<IAfPatchRecord>& record)
 {
     Mutex::Autolock _l(mLock);
     if (mSource == record->getSource()) {
@@ -9746,7 +9790,7 @@
     destroyTrack_l(record);
 }
 
-void AudioFlinger::RecordThread::toAudioPortConfig(struct audio_port_config *config)
+void RecordThread::toAudioPortConfig(struct audio_port_config* config)
 {
     ThreadBase::toAudioPortConfig(config);
     config->role = AUDIO_PORT_ROLE_SINK;
@@ -9762,56 +9806,85 @@
 //      Mmap
 // ----------------------------------------------------------------------------
 
-AudioFlinger::MmapThreadHandle::MmapThreadHandle(const sp<MmapThread>& thread)
+// Mmap stream control interface implementation. Each MmapThreadHandle controls one
+// MmapPlaybackThread or MmapCaptureThread instance.
+class MmapThreadHandle : public MmapStreamInterface {
+public:
+    explicit MmapThreadHandle(const sp<IAfMmapThread>& thread);
+    ~MmapThreadHandle() override;
+
+    // MmapStreamInterface virtuals
+    status_t createMmapBuffer(int32_t minSizeFrames,
+        struct audio_mmap_buffer_info* info) final;
+    status_t getMmapPosition(struct audio_mmap_position* position) final;
+    status_t getExternalPosition(uint64_t* position, int64_t* timeNanos) final;
+    status_t start(const AudioClient& client,
+           const audio_attributes_t* attr, audio_port_handle_t* handle) final;
+    status_t stop(audio_port_handle_t handle) final;
+    status_t standby() final;
+    status_t reportData(const void* buffer, size_t frameCount) final;
+private:
+    const sp<IAfMmapThread> mThread;
+};
+
+/* static */
+sp<MmapStreamInterface> IAfMmapThread::createMmapStreamInterfaceAdapter(
+        const sp<IAfMmapThread>& mmapThread) {
+    return sp<MmapThreadHandle>::make(mmapThread);
+}
+
+MmapThreadHandle::MmapThreadHandle(const sp<IAfMmapThread>& thread)
     : mThread(thread)
 {
     assert(thread != 0); // thread must start non-null and stay non-null
 }
 
-AudioFlinger::MmapThreadHandle::~MmapThreadHandle()
+// MmapStreamInterface could be directly implemented by MmapThread excepting this
+// special handling on adapter dtor.
+MmapThreadHandle::~MmapThreadHandle()
 {
     mThread->disconnect();
 }
 
-status_t AudioFlinger::MmapThreadHandle::createMmapBuffer(int32_t minSizeFrames,
+status_t MmapThreadHandle::createMmapBuffer(int32_t minSizeFrames,
                                   struct audio_mmap_buffer_info *info)
 {
     return mThread->createMmapBuffer(minSizeFrames, info);
 }
 
-status_t AudioFlinger::MmapThreadHandle::getMmapPosition(struct audio_mmap_position *position)
+status_t MmapThreadHandle::getMmapPosition(struct audio_mmap_position* position)
 {
     return mThread->getMmapPosition(position);
 }
 
-status_t AudioFlinger::MmapThreadHandle::getExternalPosition(uint64_t *position,
+status_t MmapThreadHandle::getExternalPosition(uint64_t* position,
                                                              int64_t *timeNanos) {
     return mThread->getExternalPosition(position, timeNanos);
 }
 
-status_t AudioFlinger::MmapThreadHandle::start(const AudioClient& client,
+status_t MmapThreadHandle::start(const AudioClient& client,
         const audio_attributes_t *attr, audio_port_handle_t *handle)
-
 {
     return mThread->start(client, attr, handle);
 }
 
-status_t AudioFlinger::MmapThreadHandle::stop(audio_port_handle_t handle)
+status_t MmapThreadHandle::stop(audio_port_handle_t handle)
 {
     return mThread->stop(handle);
 }
 
-status_t AudioFlinger::MmapThreadHandle::standby()
+status_t MmapThreadHandle::standby()
 {
     return mThread->standby();
 }
 
-status_t AudioFlinger::MmapThreadHandle::reportData(const void* buffer, size_t frameCount) {
+status_t MmapThreadHandle::reportData(const void* buffer, size_t frameCount)
+{
     return mThread->reportData(buffer, frameCount);
 }
 
 
-AudioFlinger::MmapThread::MmapThread(
+MmapThread::MmapThread(
         const sp<AudioFlinger>& audioFlinger, audio_io_handle_t id,
         AudioHwDevice *hwDev, const sp<StreamHalInterface>& stream, bool systemReady, bool isOut)
     : ThreadBase(audioFlinger, id, (isOut ? MMAP_PLAYBACK : MMAP_CAPTURE), systemReady, isOut),
@@ -9826,16 +9899,12 @@
     readHalParameters_l();
 }
 
-AudioFlinger::MmapThread::~MmapThread()
-{
-}
-
-void AudioFlinger::MmapThread::onFirstRef()
+void MmapThread::onFirstRef()
 {
     run(mThreadName, ANDROID_PRIORITY_URGENT_AUDIO);
 }
 
-void AudioFlinger::MmapThread::disconnect()
+void MmapThread::disconnect()
 {
     ActiveTracks<IAfMmapTrack> activeTracks;
     {
@@ -9856,7 +9925,7 @@
 }
 
 
-void AudioFlinger::MmapThread::configure(const audio_attributes_t *attr,
+void MmapThread::configure(const audio_attributes_t* attr,
                                                 audio_stream_type_t streamType __unused,
                                                 audio_session_t sessionId,
                                                 const sp<MmapStreamCallback>& callback,
@@ -9870,7 +9939,7 @@
     mPortId = portId;
 }
 
-status_t AudioFlinger::MmapThread::createMmapBuffer(int32_t minSizeFrames,
+status_t MmapThread::createMmapBuffer(int32_t minSizeFrames,
                                   struct audio_mmap_buffer_info *info)
 {
     if (mHalStream == 0) {
@@ -9880,7 +9949,7 @@
     return mHalStream->createMmapBuffer(minSizeFrames, info);
 }
 
-status_t AudioFlinger::MmapThread::getMmapPosition(struct audio_mmap_position *position)
+status_t MmapThread::getMmapPosition(struct audio_mmap_position* position) const
 {
     if (mHalStream == 0) {
         return NO_INIT;
@@ -9888,7 +9957,7 @@
     return mHalStream->getMmapPosition(position);
 }
 
-status_t AudioFlinger::MmapThread::exitStandby_l()
+status_t MmapThread::exitStandby_l()
 {
     // The HAL must receive track metadata before starting the stream
     updateMetadata_l();
@@ -9905,7 +9974,7 @@
     return NO_ERROR;
 }
 
-status_t AudioFlinger::MmapThread::start(const AudioClient& client,
+status_t MmapThread::start(const AudioClient& client,
                                          const audio_attributes_t *attr,
                                          audio_port_handle_t *handle)
 {
@@ -10052,7 +10121,7 @@
     return ret;
 }
 
-status_t AudioFlinger::MmapThread::stop(audio_port_handle_t handle)
+status_t MmapThread::stop(audio_port_handle_t handle)
 {
     ALOGV("%s handle %d", __FUNCTION__, handle);
 
@@ -10106,7 +10175,7 @@
     return NO_ERROR;
 }
 
-status_t AudioFlinger::MmapThread::standby()
+status_t MmapThread::standby()
 {
     ALOGV("%s", __FUNCTION__);
 
@@ -10126,12 +10195,12 @@
     return NO_ERROR;
 }
 
-status_t AudioFlinger::MmapThread::reportData(const void* /*buffer*/, size_t /*frameCount*/) {
+status_t MmapThread::reportData(const void* /*buffer*/, size_t /*frameCount*/) {
     // This is a stub implementation. The MmapPlaybackThread overrides this function.
     return INVALID_OPERATION;
 }
 
-void AudioFlinger::MmapThread::readHalParameters_l()
+void MmapThread::readHalParameters_l()
 {
     status_t result = mHalStream->getAudioProperties(&mSampleRate, &mChannelMask, &mHALFormat);
     LOG_ALWAYS_FATAL_IF(result != OK, "Error retrieving audio properties from HAL: %d", result);
@@ -10167,7 +10236,7 @@
         .record();
 }
 
-bool AudioFlinger::MmapThread::threadLoop()
+bool MmapThread::threadLoop()
 {
     checkSilentMode_l();
 
@@ -10238,7 +10307,7 @@
 }
 
 // checkForNewParameter_l() must be called with ThreadBase::mLock held
-bool AudioFlinger::MmapThread::checkForNewParameter_l(const String8& keyValuePair,
+bool MmapThread::checkForNewParameter_l(const String8& keyValuePair,
                                                               status_t& status)
 {
     AudioParameter param = AudioParameter(keyValuePair);
@@ -10256,7 +10325,7 @@
     return false;
 }
 
-String8 AudioFlinger::MmapThread::getParameters(const String8& keys)
+String8 MmapThread::getParameters(const String8& keys)
 {
     Mutex::Autolock _l(mLock);
     String8 out_s8;
@@ -10266,7 +10335,7 @@
     return {};
 }
 
-void AudioFlinger::MmapThread::ioConfigChanged(audio_io_config_event_t event, pid_t pid,
+void MmapThread::ioConfigChanged(audio_io_config_event_t event, pid_t pid,
                                                audio_port_handle_t portId __unused) {
     sp<AudioIoDescriptor> desc;
     bool isInput = false;
@@ -10291,7 +10360,7 @@
     mAudioFlinger->ioConfigChanged(event, desc, pid);
 }
 
-status_t AudioFlinger::MmapThread::createAudioPatch_l(const struct audio_patch *patch,
+status_t MmapThread::createAudioPatch_l(const struct audio_patch* patch,
                                                           audio_patch_handle_t *handle)
 NO_THREAD_SAFETY_ANALYSIS  // elease and re-acquire mLock
 {
@@ -10382,7 +10451,7 @@
     return status;
 }
 
-status_t AudioFlinger::MmapThread::releaseAudioPatch_l(const audio_patch_handle_t handle)
+status_t MmapThread::releaseAudioPatch_l(const audio_patch_handle_t handle)
 {
     status_t status = NO_ERROR;
 
@@ -10404,7 +10473,7 @@
     return status;
 }
 
-void AudioFlinger::MmapThread::toAudioPortConfig(struct audio_port_config *config)
+void MmapThread::toAudioPortConfig(struct audio_port_config* config)
 {
     ThreadBase::toAudioPortConfig(config);
     if (isOutput()) {
@@ -10418,7 +10487,7 @@
     }
 }
 
-status_t AudioFlinger::MmapThread::addEffectChain_l(const sp<IAfEffectChain>& chain)
+status_t MmapThread::addEffectChain_l(const sp<IAfEffectChain>& chain)
 {
     audio_session_t session = chain->sessionId();
 
@@ -10442,7 +10511,7 @@
     return NO_ERROR;
 }
 
-size_t AudioFlinger::MmapThread::removeEffectChain_l(const sp<IAfEffectChain>& chain)
+size_t MmapThread::removeEffectChain_l(const sp<IAfEffectChain>& chain)
 {
     audio_session_t session = chain->sessionId();
 
@@ -10465,29 +10534,29 @@
     return mEffectChains.size();
 }
 
-void AudioFlinger::MmapThread::threadLoop_standby()
+void MmapThread::threadLoop_standby()
 {
     mHalStream->standby();
 }
 
-void AudioFlinger::MmapThread::threadLoop_exit()
+void MmapThread::threadLoop_exit()
 {
     // Do not call callback->onTearDown() because it is redundant for thread exit
     // and because it can cause a recursive mutex lock on stop().
 }
 
-status_t AudioFlinger::MmapThread::setSyncEvent(const sp<audioflinger::SyncEvent>& /* event */)
+status_t MmapThread::setSyncEvent(const sp<SyncEvent>& /* event */)
 {
     return BAD_VALUE;
 }
 
-bool AudioFlinger::MmapThread::isValidSyncEvent(
-        const sp<audioflinger::SyncEvent>& /* event */) const
+bool MmapThread::isValidSyncEvent(
+        const sp<SyncEvent>& /* event */) const
 {
     return false;
 }
 
-status_t AudioFlinger::MmapThread::checkEffectCompatibility_l(
+status_t MmapThread::checkEffectCompatibility_l(
         const effect_descriptor_t *desc, audio_session_t sessionId)
 {
     // No global effect sessions on mmap threads
@@ -10521,7 +10590,7 @@
     return NO_ERROR;
 }
 
-void AudioFlinger::MmapThread::checkInvalidTracks_l()
+void MmapThread::checkInvalidTracks_l()
 NO_THREAD_SAFETY_ANALYSIS  // release and re-acquire mLock
 {
     sp<MmapStreamCallback> callback;
@@ -10542,7 +10611,7 @@
     }
 }
 
-void AudioFlinger::MmapThread::dumpInternals_l(int fd, const Vector<String16>& args __unused)
+void MmapThread::dumpInternals_l(int fd, const Vector<String16>& /* args */)
 {
     dprintf(fd, "  Attributes: content type %d usage %d source %d\n",
             mAttr.content_type, mAttr.usage, mAttr.source);
@@ -10552,7 +10621,7 @@
     }
 }
 
-void AudioFlinger::MmapThread::dumpTracks_l(int fd, const Vector<String16>& args __unused)
+void MmapThread::dumpTracks_l(int fd, const Vector<String16>& /* args */)
 {
     String8 result;
     size_t numtracks = mActiveTracks.size();
@@ -10572,7 +10641,14 @@
     write(fd, result.string(), result.size());
 }
 
-AudioFlinger::MmapPlaybackThread::MmapPlaybackThread(
+/* static */
+sp<IAfMmapPlaybackThread> IAfMmapPlaybackThread::create(
+        const sp<AudioFlinger>& audioFlinger, audio_io_handle_t id,
+        AudioHwDevice* hwDev,  AudioStreamOut* output, bool systemReady) {
+    return sp<MmapPlaybackThread>::make(audioFlinger, id, hwDev, output, systemReady);
+}
+
+MmapPlaybackThread::MmapPlaybackThread(
         const sp<AudioFlinger>& audioFlinger, audio_io_handle_t id,
         AudioHwDevice *hwDev,  AudioStreamOut *output, bool systemReady)
     : MmapThread(audioFlinger, id, hwDev, output->stream, systemReady, true /* isOut */),
@@ -10606,7 +10682,7 @@
     }
 }
 
-void AudioFlinger::MmapPlaybackThread::configure(const audio_attributes_t *attr,
+void MmapPlaybackThread::configure(const audio_attributes_t* attr,
                                                 audio_stream_type_t streamType,
                                                 audio_session_t sessionId,
                                                 const sp<MmapStreamCallback>& callback,
@@ -10617,7 +10693,7 @@
     mStreamType = streamType;
 }
 
-AudioStreamOut* AudioFlinger::MmapPlaybackThread::clearOutput()
+AudioStreamOut* MmapPlaybackThread::clearOutput()
 {
     Mutex::Autolock _l(mLock);
     AudioStreamOut *output = mOutput;
@@ -10625,7 +10701,7 @@
     return output;
 }
 
-void AudioFlinger::MmapPlaybackThread::setMasterVolume(float value)
+void MmapPlaybackThread::setMasterVolume(float value)
 {
     Mutex::Autolock _l(mLock);
     // Don't apply master volume in SW if our HAL can do it for us.
@@ -10637,7 +10713,7 @@
     }
 }
 
-void AudioFlinger::MmapPlaybackThread::setMasterMute(bool muted)
+void MmapPlaybackThread::setMasterMute(bool muted)
 {
     Mutex::Autolock _l(mLock);
     // Don't apply master mute in SW if our HAL can do it for us.
@@ -10648,7 +10724,7 @@
     }
 }
 
-void AudioFlinger::MmapPlaybackThread::setStreamVolume(audio_stream_type_t stream, float value)
+void MmapPlaybackThread::setStreamVolume(audio_stream_type_t stream, float value)
 {
     Mutex::Autolock _l(mLock);
     mStreamTypes[stream].volume = value;
@@ -10657,13 +10733,13 @@
     }
 }
 
-float AudioFlinger::MmapPlaybackThread::streamVolume(audio_stream_type_t stream) const
+float MmapPlaybackThread::streamVolume(audio_stream_type_t stream) const
 {
     Mutex::Autolock _l(mLock);
     return mStreamTypes[stream].volume;
 }
 
-void AudioFlinger::MmapPlaybackThread::setStreamMute(audio_stream_type_t stream, bool muted)
+void MmapPlaybackThread::setStreamMute(audio_stream_type_t stream, bool muted)
 {
     Mutex::Autolock _l(mLock);
     mStreamTypes[stream].mute = muted;
@@ -10672,7 +10748,7 @@
     }
 }
 
-void AudioFlinger::MmapPlaybackThread::invalidateTracks(audio_stream_type_t streamType)
+void MmapPlaybackThread::invalidateTracks(audio_stream_type_t streamType)
 {
     Mutex::Autolock _l(mLock);
     if (streamType == mStreamType) {
@@ -10683,7 +10759,7 @@
     }
 }
 
-void AudioFlinger::MmapPlaybackThread::invalidateTracks(std::set<audio_port_handle_t>& portIds)
+void MmapPlaybackThread::invalidateTracks(std::set<audio_port_handle_t>& portIds)
 {
     Mutex::Autolock _l(mLock);
     bool trackMatch = false;
@@ -10702,7 +10778,7 @@
     }
 }
 
-void AudioFlinger::MmapPlaybackThread::processVolume_l()
+void MmapPlaybackThread::processVolume_l()
 NO_THREAD_SAFETY_ANALYSIS // access of track->processMuteEvent_l
 {
     float volume;
@@ -10757,7 +10833,7 @@
     }
 }
 
-AudioFlinger::ThreadBase::MetadataUpdate AudioFlinger::MmapPlaybackThread::updateMetadata_l()
+ThreadBase::MetadataUpdate MmapPlaybackThread::updateMetadata_l()
 {
     if (!isStreamInitialized() || !mActiveTracks.readAndClearHasChanged()) {
         return {}; // nothing to do
@@ -10782,7 +10858,7 @@
     return change;
 };
 
-void AudioFlinger::MmapPlaybackThread::checkSilentMode_l()
+void MmapPlaybackThread::checkSilentMode_l()
 {
     if (!mMasterMute) {
         char value[PROPERTY_VALUE_MAX];
@@ -10799,7 +10875,7 @@
     }
 }
 
-void AudioFlinger::MmapPlaybackThread::toAudioPortConfig(struct audio_port_config *config)
+void MmapPlaybackThread::toAudioPortConfig(struct audio_port_config* config)
 {
     MmapThread::toAudioPortConfig(config);
     if (mOutput && mOutput->flags != AUDIO_OUTPUT_FLAG_NONE) {
@@ -10808,8 +10884,8 @@
     }
 }
 
-status_t AudioFlinger::MmapPlaybackThread::getExternalPosition(uint64_t *position,
-                                                               int64_t *timeNanos)
+status_t MmapPlaybackThread::getExternalPosition(uint64_t* position,
+        int64_t* timeNanos) const
 {
     if (mOutput == nullptr) {
         return NO_INIT;
@@ -10822,7 +10898,7 @@
     return status;
 }
 
-status_t AudioFlinger::MmapPlaybackThread::reportData(const void* buffer, size_t frameCount) {
+status_t MmapPlaybackThread::reportData(const void* buffer, size_t frameCount) {
     // Send to MelProcessor for sound dose measurement.
     auto processor = mMelProcessor.load();
     if (processor) {
@@ -10833,7 +10909,7 @@
 }
 
 // startMelComputation_l() must be called with AudioFlinger::mLock held
-void AudioFlinger::MmapPlaybackThread::startMelComputation_l(
+void MmapPlaybackThread::startMelComputation_l(
         const sp<audio_utils::MelProcessor>& processor)
 {
     ALOGV("%s: starting mel processor for thread %d", __func__, id());
@@ -10847,7 +10923,7 @@
 }
 
 // stopMelComputation_l() must be called with AudioFlinger::mLock held
-void AudioFlinger::MmapPlaybackThread::stopMelComputation_l()
+void MmapPlaybackThread::stopMelComputation_l()
 {
     ALOGV("%s: pausing mel processor for thread %d", __func__, id());
     auto melProcessor = mMelProcessor.load();
@@ -10856,7 +10932,7 @@
     }
 }
 
-void AudioFlinger::MmapPlaybackThread::dumpInternals_l(int fd, const Vector<String16>& args)
+void MmapPlaybackThread::dumpInternals_l(int fd, const Vector<String16>& args)
 {
     MmapThread::dumpInternals_l(fd, args);
 
@@ -10865,7 +10941,14 @@
     dprintf(fd, "  Master volume: %f Master mute %d\n", mMasterVolume, mMasterMute);
 }
 
-AudioFlinger::MmapCaptureThread::MmapCaptureThread(
+/* static */
+sp<IAfMmapCaptureThread> IAfMmapCaptureThread::create(
+        const sp<AudioFlinger>& audioFlinger, audio_io_handle_t id,
+        AudioHwDevice* hwDev,  AudioStreamIn* input, bool systemReady) {
+    return sp<MmapCaptureThread>::make(audioFlinger, id, hwDev, input, systemReady);
+}
+
+MmapCaptureThread::MmapCaptureThread(
         const sp<AudioFlinger>& audioFlinger, audio_io_handle_t id,
         AudioHwDevice *hwDev,  AudioStreamIn *input, bool systemReady)
     : MmapThread(audioFlinger, id, hwDev, input->stream, systemReady, false /* isOut */),
@@ -10875,7 +10958,7 @@
     mChannelCount = audio_channel_count_from_in_mask(mChannelMask);
 }
 
-status_t AudioFlinger::MmapCaptureThread::exitStandby_l()
+status_t MmapCaptureThread::exitStandby_l()
 {
     {
         // mInput might have been cleared by clearInput()
@@ -10886,7 +10969,7 @@
     return MmapThread::exitStandby_l();
 }
 
-AudioFlinger::AudioStreamIn* AudioFlinger::MmapCaptureThread::clearInput()
+AudioStreamIn* MmapCaptureThread::clearInput()
 {
     Mutex::Autolock _l(mLock);
     AudioStreamIn *input = mInput;
@@ -10894,8 +10977,7 @@
     return input;
 }
 
-
-void AudioFlinger::MmapCaptureThread::processVolume_l()
+void MmapCaptureThread::processVolume_l()
 {
     bool changed = false;
     bool silenced = false;
@@ -10922,7 +11004,7 @@
     }
 }
 
-AudioFlinger::ThreadBase::MetadataUpdate AudioFlinger::MmapCaptureThread::updateMetadata_l()
+ThreadBase::MetadataUpdate MmapCaptureThread::updateMetadata_l()
 {
     if (!isStreamInitialized() || !mActiveTracks.readAndClearHasChanged()) {
         return {}; // nothing to do
@@ -10945,7 +11027,7 @@
     return change;
 }
 
-void AudioFlinger::MmapCaptureThread::setRecordSilenced(audio_port_handle_t portId, bool silenced)
+void MmapCaptureThread::setRecordSilenced(audio_port_handle_t portId, bool silenced)
 {
     Mutex::Autolock _l(mLock);
     for (size_t i = 0; i < mActiveTracks.size() ; i++) {
@@ -10957,7 +11039,7 @@
     setClientSilencedIfExists_l(portId, silenced);
 }
 
-void AudioFlinger::MmapCaptureThread::toAudioPortConfig(struct audio_port_config *config)
+void MmapCaptureThread::toAudioPortConfig(struct audio_port_config* config)
 {
     MmapThread::toAudioPortConfig(config);
     if (mInput && mInput->flags != AUDIO_INPUT_FLAG_NONE) {
@@ -10966,8 +11048,8 @@
     }
 }
 
-status_t AudioFlinger::MmapCaptureThread::getExternalPosition(
-        uint64_t *position, int64_t *timeNanos)
+status_t MmapCaptureThread::getExternalPosition(
+        uint64_t* position, int64_t* timeNanos) const
 {
     if (mInput == nullptr) {
         return NO_INIT;
@@ -10977,11 +11059,18 @@
 
 // ----------------------------------------------------------------------------
 
-AudioFlinger::BitPerfectThread::BitPerfectThread(const sp<AudioFlinger> &audioflinger,
+/* static */
+sp<IAfPlaybackThread> IAfPlaybackThread::createBitPerfectThread(
+        const sp<AudioFlinger>& audioflinger,
+        AudioStreamOut* output, audio_io_handle_t id, bool systemReady) {
+    return sp<BitPerfectThread>::make(audioflinger, output, id, systemReady);
+}
+
+BitPerfectThread::BitPerfectThread(const sp<AudioFlinger> &audioflinger,
         AudioStreamOut *output, audio_io_handle_t id, bool systemReady)
         : MixerThread(audioflinger, output, id, systemReady, BIT_PERFECT) {}
 
-AudioFlinger::PlaybackThread::mixer_state AudioFlinger::BitPerfectThread::prepareTracks_l(
+PlaybackThread::mixer_state BitPerfectThread::prepareTracks_l(
         Vector<sp<IAfTrack>>* tracksToRemove) {
     mixer_state result = MixerThread::prepareTracks_l(tracksToRemove);
     // If there is only one active track and it is bit-perfect, enable tee buffer.
@@ -11014,7 +11103,7 @@
     return result;
 }
 
-void AudioFlinger::BitPerfectThread::threadLoop_mix() {
+void BitPerfectThread::threadLoop_mix() {
     MixerThread::threadLoop_mix();
     mHasDataCopiedToSinkBuffer = mIsBitPerfect;
 }
diff --git a/services/audioflinger/Threads.h b/services/audioflinger/Threads.h
index bd0cb68..a8847d7 100644
--- a/services/audioflinger/Threads.h
+++ b/services/audioflinger/Threads.h
@@ -15,39 +15,24 @@
 ** limitations under the License.
 */
 
-#ifndef INCLUDING_FROM_AUDIOFLINGER_H
-    #error This header file should only be included from AudioFlinger.h
-#endif
+#pragma once
 
-public: // TODO(b/288339104) extract out of AudioFlinger class
-class ThreadBase : public Thread {
-    // TODO(b/288339104) remove friends
-    friend class RecordTrack;
-    friend class Track;
-    friend class TrackBase;
+namespace android {
+
+class AsyncCallbackThread;
+
+class ThreadBase : public virtual IAfThreadBase, public Thread {
 public:
-    enum type_t {
-        MIXER,              // Thread class is MixerThread
-        DIRECT,             // Thread class is DirectOutputThread
-        DUPLICATING,        // Thread class is DuplicatingThread
-        RECORD,             // Thread class is RecordThread
-        OFFLOAD,            // Thread class is OffloadThread
-        MMAP_PLAYBACK,      // Thread class for MMAP playback stream
-        MMAP_CAPTURE,       // Thread class for MMAP capture stream
-        SPATIALIZER,  //
-        BIT_PERFECT,        // Thread class for BitPerfectThread
-        // If you add any values here, also update ThreadBase::threadTypeToString()
-    };
-
     static const char *threadTypeToString(type_t type);
 
+    AudioFlinger* audioFlinger() const final { return mAudioFlinger.get(); }
+
     ThreadBase(const sp<AudioFlinger>& audioFlinger, audio_io_handle_t id,
                type_t type, bool systemReady, bool isOut);
-    virtual             ~ThreadBase();
+    ~ThreadBase() override;
 
-    virtual status_t    readyToRun();
-
-    void clearPowerManager();
+    status_t readyToRun() final;
+    void clearPowerManager() final;
 
     // base for record and playback
     enum {
@@ -91,8 +76,6 @@
 
     class ConfigEvent: public RefBase {
     public:
-        virtual ~ConfigEvent() {}
-
         void dump(char *buffer, size_t size) {
             snprintf(buffer, size, "Event type: %d\n", mType);
             if (mData != nullptr) {
@@ -136,7 +119,6 @@
             ConfigEvent(CFG_EVENT_IO) {
             mData = new IoConfigEventData(event, pid, portId);
         }
-        virtual ~IoConfigEvent() {}
     };
 
     class PrioConfigEventData : public ConfigEventData {
@@ -161,7 +143,6 @@
             ConfigEvent(CFG_EVENT_PRIO, true) {
             mData = new PrioConfigEventData(pid, tid, prio, forApp);
         }
-        virtual ~PrioConfigEvent() {}
     };
 
     class SetParameterConfigEventData : public ConfigEventData {
@@ -183,7 +164,6 @@
             mData = new SetParameterConfigEventData(keyValuePairs);
             mWaitStatus = true;
         }
-        virtual ~SetParameterConfigEvent() {}
     };
 
     class CreateAudioPatchConfigEventData : public ConfigEventData {
@@ -208,7 +188,6 @@
             mData = new CreateAudioPatchConfigEventData(patch, handle);
             mWaitStatus = true;
         }
-        virtual ~CreateAudioPatchConfigEvent() {}
     };
 
     class ReleaseAudioPatchConfigEventData : public ConfigEventData {
@@ -230,7 +209,6 @@
             mData = new ReleaseAudioPatchConfigEventData(handle);
             mWaitStatus = true;
         }
-        virtual ~ReleaseAudioPatchConfigEvent() {}
     };
 
     class UpdateOutDevicesConfigEventData : public ConfigEventData {
@@ -251,8 +229,6 @@
             ConfigEvent(CFG_EVENT_UPDATE_OUT_DEVICE) {
             mData = new UpdateOutDevicesConfigEventData(outDevices);
         }
-
-        virtual ~UpdateOutDevicesConfigEvent();
     };
 
     class ResizeBufferConfigEventData : public ConfigEventData {
@@ -273,8 +249,6 @@
             ConfigEvent(CFG_EVENT_RESIZE_BUFFER) {
             mData = new ResizeBufferConfigEventData(maxSharedAudioHistoryMs);
         }
-
-        virtual ~ResizeBufferConfigEvent() {}
     };
 
     class CheckOutputStageEffectsEvent : public ConfigEvent {
@@ -282,8 +256,6 @@
         CheckOutputStageEffectsEvent() :
             ConfigEvent(CFG_EVENT_CHECK_OUTPUT_STAGE_EFFECTS) {
         }
-
-        virtual ~CheckOutputStageEffectsEvent() {}
     };
 
     class HalLatencyModesChangedEvent : public ConfigEvent {
@@ -291,8 +263,6 @@
         HalLatencyModesChangedEvent() :
             ConfigEvent(CFG_EVENT_HAL_LATENCY_MODES_CHANGED) {
         }
-
-        virtual ~HalLatencyModesChangedEvent() {}
     };
 
 
@@ -310,108 +280,87 @@
         wp<ThreadBase> mThread;
     };
 
-    virtual     status_t    initCheck() const = 0;
+    type_t type() const final { return mType; }
+    bool isDuplicating() const final { return (mType == DUPLICATING); }
+    audio_io_handle_t id() const final { return mId;}
 
-                // static externally-visible
-                type_t      type() const { return mType; }
-                bool isDuplicating() const { return (mType == DUPLICATING); }
-
-                audio_io_handle_t id() const { return mId;}
-
-                // dynamic externally-visible
-                uint32_t    sampleRate() const { return mSampleRate; }
-                audio_channel_mask_t channelMask() const { return mChannelMask; }
-    virtual     audio_channel_mask_t mixerChannelMask() const { return mChannelMask; }
-
-                audio_format_t format() const { return mHALFormat; }
-                uint32_t channelCount() const { return mChannelCount; }
-
-                // Called by AudioFlinger::frameCount(audio_io_handle_t output) and effects,
-                // and returns the [normal mix] buffer's frame count.
-    virtual     size_t      frameCount() const = 0;
-    virtual     audio_channel_mask_t hapticChannelMask() const { return AUDIO_CHANNEL_NONE; }
-    virtual     uint32_t    latency_l() const { return 0; }
-    virtual     void        setVolumeForOutput_l(float left __unused, float right __unused) const {}
+    uint32_t sampleRate() const final { return mSampleRate; }
+    audio_channel_mask_t channelMask() const final { return mChannelMask; }
+    audio_channel_mask_t mixerChannelMask() const override { return mChannelMask; }
+    audio_format_t format() const final { return mHALFormat; }
+    uint32_t channelCount() const final { return mChannelCount; }
+    audio_channel_mask_t hapticChannelMask() const override { return AUDIO_CHANNEL_NONE; }
+    uint32_t hapticChannelCount() const override { return 0; }
+    uint32_t latency_l() const override { return 0; }
+    void setVolumeForOutput_l(float /* left */, float /* right */) const override {}
 
                 // Return's the HAL's frame count i.e. fast mixer buffer size.
-                size_t      frameCountHAL() const { return mFrameCount; }
-
-                size_t      frameSize() const { return mFrameSize; }
+    size_t frameCountHAL() const final { return mFrameCount; }
+    size_t frameSize() const final { return mFrameSize; }
 
     // Should be "virtual status_t requestExitAndWait()" and override same
     // method in Thread, but Thread::requestExitAndWait() is not yet virtual.
-                void        exit();
-    virtual     bool        checkForNewParameter_l(const String8& keyValuePair,
-                                                    status_t& status) = 0;
-    virtual     status_t    setParameters(const String8& keyValuePairs);
-    virtual     String8     getParameters(const String8& keys) = 0;
-    virtual     void        ioConfigChanged(audio_io_config_event_t event, pid_t pid = 0,
-                                        audio_port_handle_t portId = AUDIO_PORT_HANDLE_NONE) = 0;
+    void exit() final;
+    status_t setParameters(const String8& keyValuePairs) final;
+
                 // sendConfigEvent_l() must be called with ThreadBase::mLock held
                 // Can temporarily release the lock if waiting for a reply from
                 // processConfigEvents_l().
-                status_t    sendConfigEvent_l(sp<ConfigEvent>& event);
-                void        sendIoConfigEvent(audio_io_config_event_t event, pid_t pid = 0,
-                                              audio_port_handle_t portId = AUDIO_PORT_HANDLE_NONE);
-                void        sendIoConfigEvent_l(audio_io_config_event_t event, pid_t pid = 0,
-                                            audio_port_handle_t portId = AUDIO_PORT_HANDLE_NONE);
-                void        sendPrioConfigEvent(pid_t pid, pid_t tid, int32_t prio, bool forApp);
-                void        sendPrioConfigEvent_l(pid_t pid, pid_t tid, int32_t prio, bool forApp);
-                status_t    sendSetParameterConfigEvent_l(const String8& keyValuePair);
-                status_t    sendCreateAudioPatchConfigEvent(const struct audio_patch *patch,
-                                                            audio_patch_handle_t *handle);
-                status_t    sendReleaseAudioPatchConfigEvent(audio_patch_handle_t handle);
-                status_t    sendUpdateOutDeviceConfigEvent(
-                                    const DeviceDescriptorBaseVector& outDevices);
-                void        sendResizeBufferConfigEvent_l(int32_t maxSharedAudioHistoryMs);
-                void        sendCheckOutputStageEffectsEvent();
-                void        sendCheckOutputStageEffectsEvent_l();
-                void        sendHalLatencyModesChangedEvent_l();
+    status_t sendConfigEvent_l(sp<ConfigEvent>& event);
+    void sendIoConfigEvent(audio_io_config_event_t event, pid_t pid = 0,
+            audio_port_handle_t portId = AUDIO_PORT_HANDLE_NONE) final;
+    void sendIoConfigEvent_l(audio_io_config_event_t event, pid_t pid = 0,
+            audio_port_handle_t portId = AUDIO_PORT_HANDLE_NONE) final;
+    void sendPrioConfigEvent(pid_t pid, pid_t tid, int32_t prio, bool forApp) final;
+    void sendPrioConfigEvent_l(pid_t pid, pid_t tid, int32_t prio, bool forApp) final;
+    status_t sendSetParameterConfigEvent_l(const String8& keyValuePair) final;
+    status_t sendCreateAudioPatchConfigEvent(const struct audio_patch* patch,
+            audio_patch_handle_t* handle) final;
+    status_t sendReleaseAudioPatchConfigEvent(audio_patch_handle_t handle) final;
+    status_t sendUpdateOutDeviceConfigEvent(
+            const DeviceDescriptorBaseVector& outDevices) final;
+    void sendResizeBufferConfigEvent_l(int32_t maxSharedAudioHistoryMs) final;
+    void sendCheckOutputStageEffectsEvent() final;
+    void sendCheckOutputStageEffectsEvent_l() final;
+    void sendHalLatencyModesChangedEvent_l() final;
 
-                void        processConfigEvents_l();
-    virtual     void        setCheckOutputStageEffects() {}
-    virtual     void        cacheParameters_l() = 0;
-    virtual     status_t    createAudioPatch_l(const struct audio_patch *patch,
-                                               audio_patch_handle_t *handle) = 0;
-    virtual     status_t    releaseAudioPatch_l(const audio_patch_handle_t handle) = 0;
-    virtual     void        updateOutDevices(const DeviceDescriptorBaseVector& outDevices);
-    virtual     void        toAudioPortConfig(struct audio_port_config *config) = 0;
+    void processConfigEvents_l() final;
+    void setCheckOutputStageEffects() override {}
+    void updateOutDevices(const DeviceDescriptorBaseVector& outDevices) override;
+    void toAudioPortConfig(struct audio_port_config* config) override;
+    void resizeInputBuffer_l(int32_t maxSharedAudioHistoryMs) override;
 
-    virtual     void        resizeInputBuffer_l(int32_t maxSharedAudioHistoryMs);
+    // see note at declaration of mStandby, mOutDevice and mInDevice
+    bool inStandby() const override { return mStandby; }
+    const DeviceTypeSet outDeviceTypes() const final {
+        return getAudioDeviceTypes(mOutDeviceTypeAddrs);
+    }
+    audio_devices_t inDeviceType() const final { return mInDeviceTypeAddr.mType; }
+    DeviceTypeSet getDeviceTypes() const final {
+        return isOutput() ? outDeviceTypes() : DeviceTypeSet({inDeviceType()});
+    }
 
-                // see note at declaration of mStandby, mOutDevice and mInDevice
-                bool        standby() const { return mStandby; }
-                const DeviceTypeSet outDeviceTypes() const {
-                    return getAudioDeviceTypes(mOutDeviceTypeAddrs);
-                }
-                audio_devices_t inDeviceType() const { return mInDeviceTypeAddr.mType; }
-                DeviceTypeSet getDeviceTypes() const {
-                    return isOutput() ? outDeviceTypes() : DeviceTypeSet({inDeviceType()});
-                }
+    const AudioDeviceTypeAddrVector& outDeviceTypeAddrs() const final {
+        return mOutDeviceTypeAddrs;
+    }
+    const AudioDeviceTypeAddr& inDeviceTypeAddr() const final {
+        return mInDeviceTypeAddr;
+    }
 
-                const AudioDeviceTypeAddrVector& outDeviceTypeAddrs() const {
-                    return mOutDeviceTypeAddrs;
-                }
-                const AudioDeviceTypeAddr& inDeviceTypeAddr() const {
-                    return mInDeviceTypeAddr;
-                }
+    bool isOutput() const final { return mIsOut; }
 
-                bool        isOutput() const { return mIsOut; }
+    bool isOffloadOrMmap() const final {
+        switch (mType) {
+        case OFFLOAD:
+        case MMAP_PLAYBACK:
+        case MMAP_CAPTURE:
+            return true;
+        default:
+            return false;
+        }
+    }
 
-                bool        isOffloadOrMmap() const {
-                    switch (mType) {
-                    case OFFLOAD:
-                    case MMAP_PLAYBACK:
-                    case MMAP_CAPTURE:
-                        return true;
-                    default:
-                        return false;
-                    }
-                }
-
-    virtual     sp<StreamHalInterface> stream() const = 0;
-
-                sp<IAfEffectHandle> createEffect_l(
+    sp<IAfEffectHandle> createEffect_l(
                                     const sp<Client>& client,
                                     const sp<media::IEffectClient>& effectClient,
                                     int32_t priority,
@@ -421,7 +370,7 @@
                                     status_t *status /*non-NULL*/,
                                     bool pinned,
                                     bool probe,
-                                    bool notifyFramesProcessed);
+                                    bool notifyFramesProcessed) final;
 
                 // return values for hasAudioSession (bit field)
                 enum effect_state {
@@ -437,47 +386,40 @@
                                                // bit-perfect track
                 };
 
-                // get effect chain corresponding to session Id.
-                sp<IAfEffectChain> getEffectChain(audio_session_t sessionId);
-                // same as getEffectChain() but must be called with ThreadBase mutex locked
-                sp<IAfEffectChain> getEffectChain_l(audio_session_t sessionId) const;
-                std::vector<int> getEffectIds_l(audio_session_t sessionId);
-                // add an effect chain to the chain list (mEffectChains)
-    virtual     status_t addEffectChain_l(const sp<IAfEffectChain>& chain) = 0;
-                // remove an effect chain from the chain list (mEffectChains)
-    virtual     size_t removeEffectChain_l(const sp<IAfEffectChain>& chain) = 0;
+    // get effect chain corresponding to session Id.
+    sp<IAfEffectChain> getEffectChain(audio_session_t sessionId) const final;
+    // same as getEffectChain() but must be called with ThreadBase mutex locked
+    sp<IAfEffectChain> getEffectChain_l(audio_session_t sessionId) const final;
+    std::vector<int> getEffectIds_l(audio_session_t sessionId) const final;
+
                 // lock all effect chains Mutexes. Must be called before releasing the
                 // ThreadBase mutex before processing the mixer and effects. This guarantees the
                 // integrity of the chains during the process.
                 // Also sets the parameter 'effectChains' to current value of mEffectChains.
-                void lockEffectChains_l(Vector<sp<IAfEffectChain>>& effectChains);
+    void lockEffectChains_l(Vector<sp<IAfEffectChain>>& effectChains) final;
                 // unlock effect chains after process
-                void unlockEffectChains(const Vector<sp<IAfEffectChain>>& effectChains);
+    void unlockEffectChains(const Vector<sp<IAfEffectChain>>& effectChains) final;
                 // get a copy of mEffectChains vector
-                Vector<sp<IAfEffectChain>> getEffectChains_l() const { return mEffectChains; };
+    Vector<sp<IAfEffectChain>> getEffectChains_l() const final { return mEffectChains; };
                 // set audio mode to all effect chains
-                void setMode(audio_mode_t mode);
+    void setMode(audio_mode_t mode) final;
                 // get effect module with corresponding ID on specified audio session
-                sp<IAfEffectModule> getEffect(audio_session_t sessionId, int effectId);
-                sp<IAfEffectModule> getEffect_l(audio_session_t sessionId, int effectId);
+    sp<IAfEffectModule> getEffect(audio_session_t sessionId, int effectId) const final;
+    sp<IAfEffectModule> getEffect_l(audio_session_t sessionId, int effectId) const final;
                 // add and effect module. Also creates the effect chain is none exists for
                 // the effects audio session. Only called in a context of moving an effect
                 // from one thread to another
-                status_t addEffect_l(const sp<IAfEffectModule>& effect);
+    status_t addEffect_l(const sp<IAfEffectModule>& effect) final;
                 // remove and effect module. Also removes the effect chain is this was the last
                 // effect
-                void removeEffect_l(const sp<IAfEffectModule>& effect, bool release = false);
+    void removeEffect_l(const sp<IAfEffectModule>& effect, bool release = false) final;
                 // disconnect an effect handle from module and destroy module if last handle
-                void disconnectEffectHandle(IAfEffectHandle *handle, bool unpinIfLast);
+    void disconnectEffectHandle(IAfEffectHandle* handle, bool unpinIfLast) final;
                 // detach all tracks connected to an auxiliary effect
-    virtual     void detachAuxEffect_l(int effectId __unused) {}
-                // returns a combination of:
-                // - EFFECT_SESSION if effects on this audio session exist in one chain
-                // - TRACK_SESSION if tracks on this audio session exist
-                // - FAST_SESSION if fast tracks on this audio session exist
-                // - SPATIALIZED_SESSION if spatialized tracks on this audio session exist
-    virtual     uint32_t hasAudioSession_l(audio_session_t sessionId) const = 0;
-                uint32_t hasAudioSession(audio_session_t sessionId) const {
+    void detachAuxEffect_l(int /* effectId */) override {}
+    // TODO(b/291317898) - remove hasAudioSession_l below.
+    uint32_t hasAudioSession_l(audio_session_t sessionId) const override = 0;
+    uint32_t hasAudioSession(audio_session_t sessionId) const final {
                     Mutex::Autolock _l(mLock);
                     return hasAudioSession_l(sessionId);
                 }
@@ -511,19 +453,17 @@
 
                 // the value returned by default implementation is not important as the
                 // strategy is only meaningful for PlaybackThread which implements this method
-                virtual product_strategy_t getStrategyForSession_l(
-                        audio_session_t sessionId __unused) {
+    product_strategy_t getStrategyForSession_l(
+            audio_session_t /* sessionId */) const override {
                     return static_cast<product_strategy_t>(0);
                 }
 
                 // check if some effects must be suspended/restored when an effect is enabled
                 // or disabled
-                void checkSuspendOnEffectEnabled(bool enabled,
+    void checkSuspendOnEffectEnabled(bool enabled,
                                                  audio_session_t sessionId,
-                                                 bool threadLocked);
+                                                 bool threadLocked) final;
 
-                virtual status_t setSyncEvent(const sp<audioflinger::SyncEvent>& event) = 0;
-                virtual bool isValidSyncEvent(const sp<audioflinger::SyncEvent>& event) const = 0;
 
                 // Return a reference to a per-thread heap which can be used to allocate IMemory
                 // objects that will be read-only to client processes, read/write to mediaserver,
@@ -531,36 +471,35 @@
                 // The heap is per-thread rather than common across all threads, because
                 // clients can't be trusted not to modify the offset of the IMemory they receive.
                 // If a thread does not have such a heap, this method returns 0.
-                virtual sp<MemoryDealer>    readOnlyHeap() const { return 0; }
+    sp<MemoryDealer> readOnlyHeap() const override { return nullptr; }
 
-                virtual sp<IMemory> pipeMemory() const { return 0; }
+    sp<IMemory> pipeMemory() const override { return nullptr; }
 
-                        void systemReady();
+    void systemReady() final;
 
-                // checkEffectCompatibility_l() must be called with ThreadBase::mLock held
-                virtual status_t    checkEffectCompatibility_l(const effect_descriptor_t *desc,
-                                                               audio_session_t sessionId) = 0;
+    void broadcast_l() final;
 
-                        void        broadcast_l();
+    bool isTimestampCorrectionEnabled() const override { return false; }
 
-                virtual bool        isTimestampCorrectionEnabled() const { return false; }
+    bool isMsdDevice() const final { return mIsMsdDevice; }
 
-                bool                isMsdDevice() const { return mIsMsdDevice; }
-
-                void                dump(int fd, const Vector<String16>& args);
+    void dump(int fd, const Vector<String16>& args) override;
 
                 // deliver stats to mediametrics.
-                void                sendStatistics(bool force);
+    void sendStatistics(bool force) final;
 
+    Mutex& mutex() const final {
+        return mLock;
+    }
     mutable     Mutex                   mLock;
 
-                void onEffectEnable(const sp<IAfEffectModule>& effect);
-                void onEffectDisable();
+    void onEffectEnable(const sp<IAfEffectModule>& effect) final;
+    void onEffectDisable() final;
 
                 // invalidateTracksForAudioSession_l must be called with holding mLock.
-    virtual     void invalidateTracksForAudioSession_l(audio_session_t sessionId __unused) const { }
+    void invalidateTracksForAudioSession_l(audio_session_t /* sessionId */) const override {}
                 // Invalidate all the tracks with the given audio session.
-                void invalidateTracksForAudioSession(audio_session_t sessionId) const {
+    void invalidateTracksForAudioSession(audio_session_t sessionId) const final {
                     Mutex::Autolock _l(mLock);
                     invalidateTracksForAudioSession_l(sessionId);
                 }
@@ -576,10 +515,8 @@
                     }
                 }
 
-    virtual     bool isStreamInitialized() = 0;
-
-    virtual     void startMelComputation_l(const sp<audio_utils::MelProcessor>& processor);
-    virtual     void stopMelComputation_l();
+    void startMelComputation_l(const sp<audio_utils::MelProcessor>& processor) override;
+    void stopMelComputation_l() override;
 
 protected:
 
@@ -603,7 +540,7 @@
                 // occurs when all suspend requests are cancelled.
                 void setEffectSuspended_l(const effect_uuid_t *type,
                                           bool suspend,
-                                          audio_session_t sessionId);
+                                          audio_session_t sessionId) final;
                 // updated mSuspendedSessions when an effect is suspended or restored
                 void        updateSuspendedSessions_l(const effect_uuid_t *type,
                                                       bool suspend,
@@ -630,7 +567,7 @@
                                 return INVALID_OPERATION;
                             }
 public:
-// TODO(b/288339104) organize with publics
+// TODO(b/291317898) organize with publics
                 product_strategy_t getStrategyForStream(audio_stream_type_t stream) const;
 protected:
 
@@ -640,9 +577,6 @@
                             { }
     virtual     void        dumpTracks_l(int fd __unused, const Vector<String16>& args __unused) { }
 
-
-    friend class AudioFlinger;      // for mEffectChains and mAudioManager
-
                 const type_t            mType;
 
                 // Used by parameters, config events, addTrack_l, exit
@@ -785,7 +719,7 @@
                     bool            isEmpty() const {
                         return mActiveTracks.isEmpty();
                     }
-                    ssize_t         indexOf(const sp<T>& item) {
+                    ssize_t indexOf(const sp<T>& item) const {
                         return mActiveTracks.indexOf(item);
                     }
                     sp<T>           operator[](size_t index) const {
@@ -846,36 +780,14 @@
                 void dumpEffectChains_l(int fd, const Vector<String16>& args);
 };
 
-class VolumeInterface {
- public:
-
-    virtual ~VolumeInterface() {}
-
-    virtual void        setMasterVolume(float value) = 0;
-    virtual void        setMasterMute(bool muted) = 0;
-    virtual void        setStreamVolume(audio_stream_type_t stream, float value) = 0;
-    virtual void        setStreamMute(audio_stream_type_t stream, bool muted) = 0;
-    virtual float       streamVolume(audio_stream_type_t stream) const = 0;
-
-};
-
 // --- PlaybackThread ---
-class PlaybackThread : public ThreadBase, public StreamOutHalInterfaceCallback,
-                       public VolumeInterface, public StreamOutHalInterfaceEventCallback {
-    // TODO(b/288339104) remove friends
-    friend class OutputTrack;
-    friend class Track;
+class PlaybackThread : public ThreadBase, public virtual IAfPlaybackThread,
+                       public StreamOutHalInterfaceCallback,
+                       public virtual VolumeInterface, public StreamOutHalInterfaceEventCallback {
 public:
-
-    enum mixer_state {
-        MIXER_IDLE,             // no active tracks
-        MIXER_TRACKS_ENABLED,   // at least one active track, but no track has any data ready
-        MIXER_TRACKS_READY,      // at least one active track, and at least one track has data
-        MIXER_DRAIN_TRACK,      // drain currently playing track
-        MIXER_DRAIN_ALL,        // fully drain the hardware
-        // standby mode does not have an enum value
-        // suspend by audio policy manager is orthogonal to mixer state
-    };
+    sp<IAfPlaybackThread> asIAfPlaybackThread() final {
+        return sp<IAfPlaybackThread>::fromExisting(this);
+    }
 
     // retry count before removing active track in case of underrun on offloaded thread:
     // we need to make sure that AudioTrack client has enough time to send large buffers
@@ -883,7 +795,6 @@
     // handled for offloaded tracks
     static const int8_t kMaxTrackRetriesOffload = 20;
     static const int8_t kMaxTrackStartupRetriesOffload = 100;
-    static const int8_t kMaxTrackStopRetriesOffload = 2;
     static constexpr uint32_t kMaxTracksPerUid = 40;
     static constexpr size_t kMaxTracks = 256;
 
@@ -896,16 +807,20 @@
     PlaybackThread(const sp<AudioFlinger>& audioFlinger, AudioStreamOut* output,
                    audio_io_handle_t id, type_t type, bool systemReady,
                    audio_config_base_t *mixerConfig = nullptr);
-    virtual             ~PlaybackThread();
+    ~PlaybackThread() override;
 
     // Thread virtuals
-    virtual     bool        threadLoop();
+    bool threadLoop() final;
 
     // RefBase
-    virtual     void        onFirstRef();
+    void onFirstRef() override;
 
-    virtual     status_t    checkEffectCompatibility_l(const effect_descriptor_t *desc,
-                                                       audio_session_t sessionId);
+    status_t checkEffectCompatibility_l(
+            const effect_descriptor_t* desc, audio_session_t sessionId) final;
+
+    void addOutputTrack_l(const sp<IAfTrack>& track) final {
+        mTracks.add(track);
+    }
 
 protected:
     // Code snippets that were lifted up out of threadLoop()
@@ -930,18 +845,21 @@
     virtual     void        onDrainReady();
     virtual     void        onError();
 
+public: // AsyncCallbackThread
                 void        resetWriteBlocked(uint32_t sequence);
                 void        resetDraining(uint32_t sequence);
+protected:
 
     virtual     bool        waitingAsyncCallback();
     virtual     bool        waitingAsyncCallback_l();
     virtual     bool        shouldStandby_l();
     virtual     void        onAddNewTrack_l();
+public:  // AsyncCallbackThread
                 void        onAsyncError(); // error reported by AsyncCallbackThread
-
+protected:
     // StreamHalInterfaceCodecFormatCallback implementation
                 void        onCodecFormatChanged(
-                                const std::basic_string<uint8_t>& metadataBs) override;
+            const std::basic_string<uint8_t>& metadataBs) final;
 
     // ThreadBase virtuals
     virtual     void        preExit();
@@ -956,29 +874,28 @@
     virtual     void        setHalLatencyMode_l() {}
 
 
-                void        dumpInternals_l(int fd, const Vector<String16>& args) override;
-                void        dumpTracks_l(int fd, const Vector<String16>& args) override;
+    void dumpInternals_l(int fd, const Vector<String16>& args) override;
+    void dumpTracks_l(int fd, const Vector<String16>& args) final;
 
 public:
 
-    virtual     status_t    initCheck() const { return (mOutput == NULL) ? NO_INIT : NO_ERROR; }
+    status_t initCheck() const final { return mOutput == nullptr ? NO_INIT : NO_ERROR; }
 
                 // return estimated latency in milliseconds, as reported by HAL
-                uint32_t    latency() const;
+    uint32_t latency() const final;
                 // same, but lock must already be held
-                uint32_t    latency_l() const override;
+    uint32_t latency_l() const final;
 
                 // VolumeInterface
-    virtual     void        setMasterVolume(float value);
-    virtual     void        setMasterBalance(float balance);
-    virtual     void        setMasterMute(bool muted);
-    virtual     void        setStreamVolume(audio_stream_type_t stream, float value);
-    virtual     void        setStreamMute(audio_stream_type_t stream, bool muted);
-    virtual     float       streamVolume(audio_stream_type_t stream) const;
+    void setMasterVolume(float value) final;
+    void setMasterBalance(float balance) override;
+    void setMasterMute(bool muted) final;
+    void setStreamVolume(audio_stream_type_t stream, float value) final;
+    void setStreamMute(audio_stream_type_t stream, bool muted) final;
+    float streamVolume(audio_stream_type_t stream) const final;
+    void setVolumeForOutput_l(float left, float right) const final;
 
-                void        setVolumeForOutput_l(float left, float right) const override;
-
-                sp<IAfTrack>   createTrack_l(
+    sp<IAfTrack> createTrack_l(
                                 const sp<Client>& client,
                                 audio_stream_type_t streamType,
                                 const audio_attributes_t& attr,
@@ -999,15 +916,20 @@
                                 audio_port_handle_t portId,
                                 const sp<media::IAudioTrackCallback>& callback,
                                 bool isSpatialized,
-                                bool isBitPerfect);
+                                bool isBitPerfect) final;
 
-                AudioStreamOut* getOutput() const;
-                AudioStreamOut* clearOutput();
-                virtual sp<StreamHalInterface> stream() const;
+    bool isTrackActive(const sp<IAfTrack>& track) const final {
+        return mActiveTracks.indexOf(track) >= 0;
+    }
+
+    AudioStreamOut* getOutput_l() const final { return mOutput; }
+    AudioStreamOut* getOutput() const final;
+    AudioStreamOut* clearOutput() final;
+    sp<StreamHalInterface> stream() const final;
 
                 // a very large number of suspend() will eventually wraparound, but unlikely
-                void        suspend() { (void) android_atomic_inc(&mSuspended); }
-                void        restore()
+    void suspend() final { (void) android_atomic_inc(&mSuspended); }
+    void restore() final
                                 {
                                     // if restore() is done without suspend(), get back into
                                     // range so that the next suspend() will operate correctly
@@ -1015,123 +937,127 @@
                                         android_atomic_release_store(0, &mSuspended);
                                     }
                                 }
-                bool        isSuspended() const
+    bool isSuspended() const final
                                 { return android_atomic_acquire_load(&mSuspended) > 0; }
 
-    virtual     String8     getParameters(const String8& keys);
-    virtual     void        ioConfigChanged(audio_io_config_event_t event, pid_t pid = 0,
-                                            audio_port_handle_t portId = AUDIO_PORT_HANDLE_NONE);
-                status_t    getRenderPosition(uint32_t *halFrames, uint32_t *dspFrames);
+    String8 getParameters(const String8& keys);
+    void ioConfigChanged(audio_io_config_event_t event, pid_t pid = 0,
+            audio_port_handle_t portId = AUDIO_PORT_HANDLE_NONE) final;
+    status_t getRenderPosition(uint32_t* halFrames, uint32_t* dspFrames) const final;
                 // Consider also removing and passing an explicit mMainBuffer initialization
                 // parameter to AF::IAfTrack::Track().
-                float *sinkBuffer() const {
+    float* sinkBuffer() const final {
                     return reinterpret_cast<float *>(mSinkBuffer); };
 
-    virtual     void detachAuxEffect_l(int effectId);
-                status_t attachAuxEffect(const sp<IAfTrack>& track,
-                        int EffectId);
-                status_t attachAuxEffect_l(const sp<IAfTrack>& track,
-                        int EffectId);
+    void detachAuxEffect_l(int effectId) final;
 
-                virtual status_t addEffectChain_l(const sp<IAfEffectChain>& chain);
-                virtual size_t removeEffectChain_l(const sp<IAfEffectChain>& chain);
-                        uint32_t hasAudioSession_l(audio_session_t sessionId) const override {
+    status_t attachAuxEffect(const sp<IAfTrack>& track, int EffectId) final;
+    status_t attachAuxEffect_l(const sp<IAfTrack>& track, int EffectId) final;
+
+    status_t addEffectChain_l(const sp<IAfEffectChain>& chain) final;
+    size_t removeEffectChain_l(const sp<IAfEffectChain>& chain) final;
+    uint32_t hasAudioSession_l(audio_session_t sessionId) const final {
                             return ThreadBase::hasAudioSession_l(sessionId, mTracks);
                         }
-                virtual product_strategy_t getStrategyForSession_l(audio_session_t sessionId);
+    product_strategy_t getStrategyForSession_l(audio_session_t sessionId) const final;
 
 
-                status_t setSyncEvent(const sp<audioflinger::SyncEvent>& event) override;
-                bool     isValidSyncEvent(const sp<audioflinger::SyncEvent>& event) const override;
+    status_t setSyncEvent(const sp<audioflinger::SyncEvent>& event) final;
+    bool isValidSyncEvent(const sp<audioflinger::SyncEvent>& event) const final;
 
                 // called with AudioFlinger lock held
-                        bool     invalidateTracks_l(audio_stream_type_t streamType);
-                        bool     invalidateTracks_l(std::set<audio_port_handle_t>& portIds);
-                virtual void     invalidateTracks(audio_stream_type_t streamType);
+    bool invalidateTracks_l(audio_stream_type_t streamType) final;
+    bool invalidateTracks_l(std::set<audio_port_handle_t>& portIds) final;
+    void invalidateTracks(audio_stream_type_t streamType) override;
                 // Invalidate tracks by a set of port ids. The port id will be removed from
                 // the given set if the corresponding track is found and invalidated.
-                virtual void     invalidateTracks(std::set<audio_port_handle_t>& portIds);
+    void invalidateTracks(std::set<audio_port_handle_t>& portIds) override;
 
-    virtual     size_t      frameCount() const { return mNormalFrameCount; }
+    size_t frameCount() const final { return mNormalFrameCount; }
 
-                audio_channel_mask_t mixerChannelMask() const override {
+    audio_channel_mask_t mixerChannelMask() const final {
                     return mMixerChannelMask;
                 }
 
-                status_t    getTimestamp_l(AudioTimestamp& timestamp);
+    status_t getTimestamp_l(AudioTimestamp& timestamp) final;
 
-                void        addPatchTrack(const sp<IAfPatchTrack>& track);
-                void        deletePatchTrack(const sp<IAfPatchTrack>& track);
+    void addPatchTrack(const sp<IAfPatchTrack>& track) final;
+    void deletePatchTrack(const sp<IAfPatchTrack>& track) final;
 
-    virtual     void        toAudioPortConfig(struct audio_port_config *config);
+    void toAudioPortConfig(struct audio_port_config* config) final;
 
                 // Return the asynchronous signal wait time.
-    virtual     int64_t     computeWaitTimeNs_l() const { return INT64_MAX; }
+    int64_t computeWaitTimeNs_l() const override { return INT64_MAX; }
                 // returns true if the track is allowed to be added to the thread.
-    virtual     bool        isTrackAllowed_l(
+    bool isTrackAllowed_l(
                                     audio_channel_mask_t channelMask __unused,
                                     audio_format_t format __unused,
                                     audio_session_t sessionId __unused,
-                                    uid_t uid) const {
+                                    uid_t uid) const override {
                                 return trackCountForUid_l(uid) < PlaybackThread::kMaxTracksPerUid
                                        && mTracks.size() < PlaybackThread::kMaxTracks;
                             }
 
-                bool        isTimestampCorrectionEnabled() const override {
+    bool isTimestampCorrectionEnabled() const final {
                                 return audio_is_output_devices(mTimestampCorrectedDevice)
                                         && outDeviceTypes().count(mTimestampCorrectedDevice) != 0;
                             }
 
-    virtual     bool        isStreamInitialized() {
+    bool isStreamInitialized() const final {
                                 return !(mOutput == nullptr || mOutput->stream == nullptr);
                             }
 
-                audio_channel_mask_t hapticChannelMask() const override {
+    audio_channel_mask_t hapticChannelMask() const final {
                                          return mHapticChannelMask;
                                      }
-                bool supportsHapticPlayback() const {
+
+    uint32_t hapticChannelCount() const final {
+        return mHapticChannelCount;
+    }
+
+    bool supportsHapticPlayback() const final {
                     return (mHapticChannelMask & AUDIO_CHANNEL_HAPTIC_ALL) != AUDIO_CHANNEL_NONE;
                 }
 
-                void setDownStreamPatch(const struct audio_patch *patch) {
+    void setDownStreamPatch(const struct audio_patch* patch) final {
                     Mutex::Autolock _l(mLock);
                     mDownStreamPatch = *patch;
                 }
 
-                IAfTrack* getTrackById_l(audio_port_handle_t trackId);
+    IAfTrack* getTrackById_l(audio_port_handle_t trackId) final;
 
-                bool hasMixer() const {
+    bool hasMixer() const final {
                     return mType == MIXER || mType == DUPLICATING || mType == SPATIALIZER;
                 }
 
-    virtual     status_t setRequestedLatencyMode(
-            audio_latency_mode_t mode __unused) { return INVALID_OPERATION; }
+    status_t setRequestedLatencyMode(
+            audio_latency_mode_t /* mode */) override { return INVALID_OPERATION; }
 
-    virtual     status_t getSupportedLatencyModes(
-                        std::vector<audio_latency_mode_t>* modes __unused) {
+    status_t getSupportedLatencyModes(
+            std::vector<audio_latency_mode_t>* /* modes */) override {
                     return INVALID_OPERATION;
                 }
 
-    virtual     status_t setBluetoothVariableLatencyEnabled(bool enabled __unused) {
+    status_t setBluetoothVariableLatencyEnabled(bool /* enabled */) override{
                     return INVALID_OPERATION;
                 }
 
-                void startMelComputation_l(const sp<audio_utils::MelProcessor>& processor) override;
-                void stopMelComputation_l() override;
+    void startMelComputation_l(const sp<audio_utils::MelProcessor>& processor) override;
+    void stopMelComputation_l() override;
 
-                void setStandby() {
+    void setStandby() final {
                     Mutex::Autolock _l(mLock);
                     setStandby_l();
                 }
 
-                void setStandby_l() {
+    void setStandby_l() final {
                     mStandby = true;
                     mHalStarted = false;
                     mKernelPositionOnStandby =
                         mTimestamp.mPosition[ExtendedTimestamp::LOCATION_KERNEL];
                 }
 
-                bool waitForHalStart() {
+    bool waitForHalStart() final {
                     Mutex::Autolock _l(mLock);
                     static const nsecs_t kWaitHalTimeoutNs = seconds(2);
                     nsecs_t endWaitTimetNs = systemTime() + kWaitHalTimeoutNs;
@@ -1246,7 +1172,6 @@
 
     audio_channel_mask_t            mMixerChannelMask = AUDIO_CHANNEL_NONE;
 
-private:
     // mMasterMute is in both PlaybackThread and in AudioFlinger.  When a
     // PlaybackThread needs to find out if master-muted, it checks it's local
     // copy rather than the one in AudioFlinger.  This optimization saves a lock.
@@ -1260,7 +1185,6 @@
                             : mTimestampVerifier.DISCONTINUITY_MODE_CONTINUOUS;
                 }
 
-protected:
     ActiveTracks<IAfTrack> mActiveTracks;
 
     // Time to sleep between cycles when:
@@ -1271,7 +1195,7 @@
     // No sleep in standby mode; waits on a condition
 
     // Code snippets that are temporarily lifted up out of threadLoop() until the merge
-                void        checkSilentMode_l();
+    virtual void checkSilentMode_l() final;  // consider unification with MMapThread
 
     // Non-trivial for DUPLICATING only
     virtual     void        saveOutputTracks() { }
@@ -1289,25 +1213,22 @@
                                    audio_patch_handle_t *handle);
     virtual     status_t    releaseAudioPatch_l(const audio_patch_handle_t handle);
 
-                bool        usesHwAvSync() const { return (mType == DIRECT) && (mOutput != NULL)
+    bool usesHwAvSync() const final { return mType == DIRECT && mOutput != nullptr
                                     && mHwSupportsPause
                                     && (mOutput->flags & AUDIO_OUTPUT_FLAG_HW_AV_SYNC); }
 
                 uint32_t    trackCountForUid_l(uid_t uid) const;
 
                 void        invalidateTracksForAudioSession_l(
-                                    audio_session_t sessionId) const override {
+    audio_session_t sessionId) const override {
                                 ThreadBase::invalidateTracksForAudioSession_l(sessionId, mTracks);
                             }
 
-private:
-
-    friend class AudioFlinger;      // for numerous
-
     DISALLOW_COPY_AND_ASSIGN(PlaybackThread);
 
-    status_t    addTrack_l(const sp<IAfTrack>& track);
-    bool        destroyTrack_l(const sp<IAfTrack>& track);
+    status_t addTrack_l(const sp<IAfTrack>& track) final;
+    bool destroyTrack_l(const sp<IAfTrack>& track) final;
+
     void        removeTrack_l(const sp<IAfTrack>& track);
 
     void        readOutputParameters_l();
@@ -1369,6 +1290,7 @@
     Tracks<IAfTrack>                   mTracks;
 
     stream_type_t                   mStreamTypes[AUDIO_STREAM_CNT];
+
     AudioStreamOut                  *mOutput;
 
     float                           mMasterVolume;
@@ -1423,19 +1345,20 @@
     // Bit 0 is reset by the async callback thread calling resetDraining(). Out of sequence
     // callbacks are ignored.
     uint32_t                        mDrainSequence;
+
     sp<AsyncCallbackThread>         mCallbackThread;
 
     Mutex                                    mAudioTrackCbLock;
     // Record of IAudioTrackCallback
     std::map<sp<IAfTrack>, sp<media::IAudioTrackCallback>> mAudioTrackCallbacks;
 
-private:
     // The HAL output sink is treated as non-blocking, but current implementation is blocking
     sp<NBAIO_Sink>          mOutputSink;
     // If a fast mixer is present, the blocking pipe sink, otherwise clear
     sp<NBAIO_Sink>          mPipeSink;
     // The current sink for the normal mixer to write it's (sub)mix, mOutputSink or mPipeSink
     sp<NBAIO_Sink>          mNormalSink;
+
     uint32_t                mScreenState;   // cached copy of gScreenState
     // TODO: add comment and adjust size as needed
     static const size_t     kFastMixerLogSize = 8 * 1024;
@@ -1453,14 +1376,14 @@
     int64_t                  mKernelPositionOnStandby = 0;
 
 public:
-    virtual     bool        hasFastMixer() const = 0;
-    virtual     FastTrackUnderruns getFastTrackUnderruns(size_t fastIndex __unused) const
-                                { FastTrackUnderruns dummy; return dummy; }
-                const std::atomic<int64_t>& framesWritten() const { return mFramesWritten; }
+    FastTrackUnderruns getFastTrackUnderruns(size_t /* fastIndex */) const override
+        { return {}; }
+    const std::atomic<int64_t>& framesWritten() const final { return mFramesWritten; }
 
 protected:
                 // accessed by both binder threads and within threadLoop(), lock on mutex needed
-                unsigned    mFastTrackAvailMask;    // bit i set if fast track [i] is available
+     uint32_t& fastTrackAvailMask_l() final { return mFastTrackAvailMask; }
+     uint32_t mFastTrackAvailMask;  // bit i set if fast track [i] is available
                 bool        mHwSupportsPause;
                 bool        mHwPaused;
                 bool        mFlushPending;
@@ -1517,30 +1440,29 @@
                 bool systemReady,
                 type_t type = MIXER,
                 audio_config_base_t *mixerConfig = nullptr);
-    virtual             ~MixerThread();
+    ~MixerThread() override;
 
     // RefBase
-    virtual     void        onFirstRef();
+    void onFirstRef() override;
 
                 // StreamOutHalInterfaceLatencyModeCallback
                 void        onRecommendedLatencyModeChanged(
-                                    std::vector<audio_latency_mode_t> modes) override;
+            std::vector<audio_latency_mode_t> modes) final;
 
     // Thread virtuals
 
-    virtual     bool        checkForNewParameter_l(const String8& keyValuePair,
-                                                   status_t& status);
+    bool checkForNewParameter_l(const String8& keyValuePair, status_t& status) final;
 
-    virtual     bool        isTrackAllowed_l(
+    bool isTrackAllowed_l(
                                     audio_channel_mask_t channelMask, audio_format_t format,
-                                    audio_session_t sessionId, uid_t uid) const override;
+                                    audio_session_t sessionId, uid_t uid) const final;
 protected:
-    virtual     mixer_state prepareTracks_l(Vector<sp<IAfTrack>>* tracksToRemove);
-    virtual     uint32_t    idleSleepTimeUs() const;
-    virtual     uint32_t    suspendSleepTimeUs() const;
-    virtual     void        cacheParameters_l();
+    mixer_state prepareTracks_l(Vector<sp<IAfTrack>>* tracksToRemove) override;
+    uint32_t idleSleepTimeUs() const final;
+    uint32_t suspendSleepTimeUs() const final;
+    void cacheParameters_l() override;
 
-    virtual void acquireWakeLock_l() {
+    void acquireWakeLock_l() final {
         PlaybackThread::acquireWakeLock_l();
         if (hasFastMixer()) {
             mFastMixer->setBoottimeOffset(
@@ -1551,15 +1473,15 @@
                 void        dumpInternals_l(int fd, const Vector<String16>& args) override;
 
     // threadLoop snippets
-    virtual     ssize_t     threadLoop_write();
-    virtual     void        threadLoop_standby();
-    virtual     void        threadLoop_mix();
-    virtual     void        threadLoop_sleepTime();
-    virtual     uint32_t    correctLatency_l(uint32_t latency) const;
+    ssize_t threadLoop_write() override;
+    void threadLoop_standby() override;
+    void threadLoop_mix() override;
+    void threadLoop_sleepTime() override;
+    uint32_t correctLatency_l(uint32_t latency) const final;
 
-    virtual     status_t    createAudioPatch_l(const struct audio_patch *patch,
-                                   audio_patch_handle_t *handle);
-    virtual     status_t    releaseAudioPatch_l(const audio_patch_handle_t handle);
+    status_t createAudioPatch_l(
+            const struct audio_patch* patch, audio_patch_handle_t* handle) final;
+    status_t releaseAudioPatch_l(const audio_patch_handle_t handle) final;
 
                 AudioMixer* mAudioMixer;    // normal mixer
 
@@ -1635,9 +1557,13 @@
                 void       setHalLatencyMode_l() override;
 };
 
-class DirectOutputThread : public PlaybackThread {
+class DirectOutputThread : public PlaybackThread, public virtual IAfDirectOutputThread {
 public:
 
+    sp<IAfDirectOutputThread> asIAfDirectOutputThread() final {
+        return sp<IAfDirectOutputThread>::fromExisting(this);
+    }
+
     DirectOutputThread(const sp<AudioFlinger>& audioFlinger, AudioStreamOut* output,
                        audio_io_handle_t id, bool systemReady,
                        const audio_offload_info_t& offloadInfo)
@@ -1645,7 +1571,7 @@
 
     virtual                 ~DirectOutputThread();
 
-                status_t    selectPresentation(int presentationId, int programId);
+    status_t selectPresentation(int presentationId, int programId) final;
 
     // Thread virtuals
 
@@ -1745,11 +1671,8 @@
 
 class AsyncCallbackThread : public Thread {
 public:
-
     explicit AsyncCallbackThread(const wp<PlaybackThread>& playbackThread);
 
-    virtual             ~AsyncCallbackThread();
-
     // Thread virtuals
     virtual bool        threadLoop();
 
@@ -1778,16 +1701,20 @@
     bool                       mAsyncError;
 };
 
-class DuplicatingThread : public MixerThread {
+class DuplicatingThread : public MixerThread, public IAfDuplicatingThread {
 public:
-    DuplicatingThread(const sp<AudioFlinger>& audioFlinger, MixerThread* mainThread,
+    DuplicatingThread(const sp<AudioFlinger>& audioFlinger, IAfPlaybackThread* mainThread,
                       audio_io_handle_t id, bool systemReady);
-    virtual                 ~DuplicatingThread();
+    ~DuplicatingThread() override;
+
+    sp<IAfDuplicatingThread> asIAfDuplicatingThread() final {
+        return sp<IAfDuplicatingThread>::fromExisting(this);
+    }
 
     // Thread virtuals
-                void        addOutputTrack(MixerThread* thread);
-                void        removeOutputTrack(MixerThread* thread);
-                uint32_t    waitTimeMs() const { return mWaitTimeMs; }
+    void addOutputTrack(IAfPlaybackThread* thread) final;
+    void removeOutputTrack(IAfPlaybackThread* thread) final;
+    uint32_t waitTimeMs() const final { return mWaitTimeMs; }
 
                 void        sendMetadataToBackend_l(
                         const StreamOutHalInterface::SourceMetadata& metadata) override;
@@ -1843,18 +1770,17 @@
                            audio_io_handle_t id,
                            bool systemReady,
                            audio_config_base_t *mixerConfig);
-            ~SpatializerThread() override {}
 
-            bool hasFastMixer() const override { return false; }
+    bool hasFastMixer() const final { return false; }
 
             // RefBase
-            virtual void        onFirstRef();
+    void onFirstRef() final;
 
-            status_t setRequestedLatencyMode(audio_latency_mode_t mode) override;
+    status_t setRequestedLatencyMode(audio_latency_mode_t mode) final;
 
 protected:
-            void checkOutputStageEffects() override;
-            void setHalLatencyMode_l() override;
+    void checkOutputStageEffects() final;
+    void setHalLatencyMode_l() final;
 
 private:
             // Do not request a specific mode by default
@@ -1864,40 +1790,39 @@
 };
 
 // record thread
-class RecordThread : public ThreadBase
+class RecordThread : public IAfRecordThread, public ThreadBase
 {
-    // TODO(b/288339104) remove friends
-    friend class PassthruPatchRecord;
-    friend class RecordTrack;
     friend class ResamplerBufferProvider;
 public:
-
+    sp<IAfRecordThread> asIAfRecordThread() final {
+        return sp<IAfRecordThread>::fromExisting(this);
+    }
 
             RecordThread(const sp<AudioFlinger>& audioFlinger,
                     AudioStreamIn *input,
                     audio_io_handle_t id,
                     bool systemReady
                     );
-            virtual     ~RecordThread();
+    ~RecordThread() override;
 
     // no addTrack_l ?
-    void        destroyTrack_l(const sp<IAfRecordTrack>& track);
-    void        removeTrack_l(const sp<IAfRecordTrack>& track);
+    void destroyTrack_l(const sp<IAfRecordTrack>& track) final;
+    void removeTrack_l(const sp<IAfRecordTrack>& track) final;
 
     // Thread virtuals
-    virtual bool        threadLoop();
-    virtual void        preExit();
+    bool threadLoop() final;
+    void preExit() final;
 
     // RefBase
-    virtual void        onFirstRef();
+    void onFirstRef() final;
 
-    virtual status_t    initCheck() const { return (mInput == NULL) ? NO_INIT : NO_ERROR; }
+    status_t initCheck() const final { return mInput == nullptr ? NO_INIT : NO_ERROR; }
 
-    virtual sp<MemoryDealer>    readOnlyHeap() const { return mReadOnlyHeap; }
+    sp<MemoryDealer> readOnlyHeap() const final { return mReadOnlyHeap; }
 
-    virtual sp<IMemory> pipeMemory() const { return mPipeMemory; }
+    sp<IMemory> pipeMemory() const final { return mPipeMemory; }
 
-            sp<IAfRecordTrack> createRecordTrack_l(
+    sp<IAfRecordTrack> createRecordTrack_l(
                     const sp<Client>& client,
                     const audio_attributes_t& attr,
                     uint32_t *pSampleRate,
@@ -1912,17 +1837,19 @@
                     pid_t tid,
                     status_t *status /*non-NULL*/,
                     audio_port_handle_t portId,
-                    int32_t maxSharedAudioHistoryMs);
+                    int32_t maxSharedAudioHistoryMs) final;
 
             status_t start(IAfRecordTrack* recordTrack,
                               AudioSystem::sync_event_t event,
-                              audio_session_t triggerSession);
+                              audio_session_t triggerSession) final;
 
             // ask the thread to stop the specified track, and
             // return true if the caller should then do it's part of the stopping process
-            bool stop(IAfRecordTrack* recordTrack);
+    bool stop(IAfRecordTrack* recordTrack) final;
+    AudioStreamIn* getInput() const final { return mInput; }
+    AudioStreamIn* clearInput() final;
 
-            AudioStreamIn* clearInput();
+            // TODO(b/291317898) Unify with IAfThreadBase
             virtual sp<StreamHalInterface> stream() const;
 
 
@@ -1930,19 +1857,19 @@
                                                status_t& status);
     virtual void        cacheParameters_l() {}
     virtual String8     getParameters(const String8& keys);
-    virtual void        ioConfigChanged(audio_io_config_event_t event, pid_t pid = 0,
-                                        audio_port_handle_t portId = AUDIO_PORT_HANDLE_NONE);
+    void ioConfigChanged(audio_io_config_event_t event, pid_t pid = 0,
+            audio_port_handle_t portId = AUDIO_PORT_HANDLE_NONE) final;
     virtual status_t    createAudioPatch_l(const struct audio_patch *patch,
                                            audio_patch_handle_t *handle);
     virtual status_t    releaseAudioPatch_l(const audio_patch_handle_t handle);
             void        updateOutDevices(const DeviceDescriptorBaseVector& outDevices) override;
             void        resizeInputBuffer_l(int32_t maxSharedAudioHistoryMs) override;
 
-            void        addPatchTrack(const sp<IAfPatchRecord>& record);
-            void        deletePatchTrack(const sp<IAfPatchRecord>& record);
+    void addPatchTrack(const sp<IAfPatchRecord>& record) final;
+    void deletePatchTrack(const sp<IAfPatchRecord>& record) final;
 
             void        readInputParameters_l();
-    virtual uint32_t    getInputFramesLost();
+    uint32_t getInputFramesLost() const final;
 
     virtual status_t addEffectChain_l(const sp<IAfEffectChain>& chain);
     virtual size_t removeEffectChain_l(const sp<IAfEffectChain>& chain);
@@ -1961,7 +1888,7 @@
     static void syncStartEventCallback(const wp<audioflinger::SyncEvent>& event);
 
     virtual size_t      frameCount() const { return mFrameCount; }
-            bool        hasFastCapture() const { return mFastCapture != 0; }
+    bool hasFastCapture() const final { return mFastCapture != 0; }
     virtual void        toAudioPortConfig(struct audio_port_config *config);
 
     virtual status_t    checkEffectCompatibility_l(const effect_descriptor_t *desc,
@@ -1972,20 +1899,20 @@
                             mActiveTracks.updatePowerState(this, true /* force */);
                         }
 
-            void        checkBtNrec();
+    void checkBtNrec() final;
 
             // Sets the UID records silence
-            void        setRecordSilenced(audio_port_handle_t portId, bool silenced);
+    void setRecordSilenced(audio_port_handle_t portId, bool silenced) final;
 
-            status_t    getActiveMicrophones(
-                    std::vector<media::MicrophoneInfoFw>* activeMicrophones);
-
-            status_t    setPreferredMicrophoneDirection(audio_microphone_direction_t direction);
-            status_t    setPreferredMicrophoneFieldDimension(float zoom);
+    status_t getActiveMicrophones(
+            std::vector<media::MicrophoneInfoFw>* activeMicrophones) const final;
+    status_t setPreferredMicrophoneDirection(audio_microphone_direction_t direction) final;
+    status_t setPreferredMicrophoneFieldDimension(float zoom) final;
 
             MetadataUpdate        updateMetadata_l() override;
 
-            bool        fastTrackAvailable() const { return mFastTrackAvail; }
+    bool fastTrackAvailable() const final { return mFastTrackAvail; }
+    void setFastTrackAvailable(bool available) final { mFastTrackAvail = available; }
 
             bool        isTimestampCorrectionEnabled() const override {
                             // checks popcount for exactly one device.
@@ -1995,15 +1922,15 @@
                                     && inDeviceType() == mTimestampCorrectedDevice;
                         }
 
-            status_t    shareAudioHistory(const std::string& sharedAudioPackageName,
+    status_t shareAudioHistory(const std::string& sharedAudioPackageName,
                                           audio_session_t sharedSessionId = AUDIO_SESSION_NONE,
-                                          int64_t sharedAudioStartMs = -1);
+            int64_t sharedAudioStartMs = -1) final;
             status_t    shareAudioHistory_l(const std::string& sharedAudioPackageName,
                                           audio_session_t sharedSessionId = AUDIO_SESSION_NONE,
                                           int64_t sharedAudioStartMs = -1);
-            void        resetAudioHistory_l();
+    void resetAudioHistory_l() final;
 
-    virtual bool        isStreamInitialized() {
+    bool isStreamInitialized() const final {
                             return !(mInput == nullptr || mInput->stream == nullptr);
                         }
 
@@ -2095,87 +2022,85 @@
             audio_session_t                     mSharedAudioSessionId = AUDIO_SESSION_NONE;
 };
 
-class MmapThread : public ThreadBase
+class MmapThread : public ThreadBase, public virtual IAfMmapThread
 {
  public:
     MmapThread(const sp<AudioFlinger>& audioFlinger, audio_io_handle_t id,
                AudioHwDevice *hwDev, const sp<StreamHalInterface>& stream, bool systemReady,
                bool isOut);
-    virtual     ~MmapThread();
 
-    virtual     void        configure(const audio_attributes_t *attr,
+    void configure(const audio_attributes_t* attr,
                                       audio_stream_type_t streamType,
                                       audio_session_t sessionId,
                                       const sp<MmapStreamCallback>& callback,
                                       audio_port_handle_t deviceId,
-                                      audio_port_handle_t portId);
+                                      audio_port_handle_t portId) override;
 
-                void        disconnect();
+    void disconnect() final;
 
-    // MmapStreamInterface
-    status_t createMmapBuffer(int32_t minSizeFrames,
-                                      struct audio_mmap_buffer_info *info);
-    status_t getMmapPosition(struct audio_mmap_position *position);
+    // MmapStreamInterface for adapter.
+    status_t createMmapBuffer(int32_t minSizeFrames, struct audio_mmap_buffer_info* info) final;
+    status_t getMmapPosition(struct audio_mmap_position* position) const override;
     status_t start(const AudioClient& client,
                    const audio_attributes_t *attr,
-                   audio_port_handle_t *handle);
-    status_t stop(audio_port_handle_t handle);
-    status_t standby();
-    virtual status_t getExternalPosition(uint64_t *position, int64_t *timeNaos) = 0;
-    virtual status_t reportData(const void* buffer, size_t frameCount);
+            audio_port_handle_t* handle) final;
+    status_t stop(audio_port_handle_t handle) final;
+    status_t standby() final;
+    status_t getExternalPosition(uint64_t* position, int64_t* timeNanos) const = 0;
+    status_t reportData(const void* buffer, size_t frameCount) override;
 
     // RefBase
-    virtual     void        onFirstRef();
+    void onFirstRef() final;
 
     // Thread virtuals
-    virtual     bool        threadLoop();
+    bool threadLoop() final;
 
-    virtual     void        threadLoop_exit();
-    virtual     void        threadLoop_standby();
-    virtual     bool        shouldStandby_l() { return false; }
-    virtual     status_t    exitStandby_l() REQUIRES(mLock);
+    // Not in ThreadBase
+    virtual void threadLoop_exit() final;
+    virtual void threadLoop_standby() final;
+    virtual bool shouldStandby_l() final { return false; }
+    virtual status_t exitStandby_l() REQUIRES(mLock);
 
-    virtual     status_t    initCheck() const { return (mHalStream == 0) ? NO_INIT : NO_ERROR; }
-    virtual     size_t      frameCount() const { return mFrameCount; }
-    virtual     bool        checkForNewParameter_l(const String8& keyValuePair,
-                                                    status_t& status);
-    virtual     String8     getParameters(const String8& keys);
-    virtual     void        ioConfigChanged(audio_io_config_event_t event, pid_t pid = 0,
-                                            audio_port_handle_t portId = AUDIO_PORT_HANDLE_NONE);
+    status_t initCheck() const final { return mHalStream == nullptr ? NO_INIT : NO_ERROR; }
+    size_t frameCount() const final { return mFrameCount; }
+    bool checkForNewParameter_l(const String8& keyValuePair, status_t& status) final;
+    String8 getParameters(const String8& keys) final;
+    void ioConfigChanged(audio_io_config_event_t event, pid_t pid = 0,
+            audio_port_handle_t portId = AUDIO_PORT_HANDLE_NONE) final;
                 void        readHalParameters_l();
-    virtual     void        cacheParameters_l() {}
-    virtual     status_t    createAudioPatch_l(const struct audio_patch *patch,
-                                               audio_patch_handle_t *handle);
-    virtual     status_t    releaseAudioPatch_l(const audio_patch_handle_t handle);
-    virtual     void        toAudioPortConfig(struct audio_port_config *config);
+    void cacheParameters_l() final {}
+    status_t createAudioPatch_l(
+            const struct audio_patch* patch, audio_patch_handle_t* handle) final;
+    status_t releaseAudioPatch_l(const audio_patch_handle_t handle) final;
+    void toAudioPortConfig(struct audio_port_config* config) override;
 
-    virtual     sp<StreamHalInterface> stream() const { return mHalStream; }
-    virtual     status_t    addEffectChain_l(const sp<IAfEffectChain>& chain);
-    virtual     size_t      removeEffectChain_l(const sp<IAfEffectChain>& chain);
-    virtual     status_t    checkEffectCompatibility_l(const effect_descriptor_t *desc,
-                                                               audio_session_t sessionId);
+    sp<StreamHalInterface> stream() const final { return mHalStream; }
+    status_t addEffectChain_l(const sp<IAfEffectChain>& chain) final;
+    size_t removeEffectChain_l(const sp<IAfEffectChain>& chain) final;
+    status_t checkEffectCompatibility_l(
+            const effect_descriptor_t *desc, audio_session_t sessionId) final;
 
-                uint32_t    hasAudioSession_l(audio_session_t sessionId) const override {
+    uint32_t hasAudioSession_l(audio_session_t sessionId) const override {
                                 // Note: using mActiveTracks as no mTracks here.
                                 return ThreadBase::hasAudioSession_l(sessionId, mActiveTracks);
                             }
-    virtual     status_t    setSyncEvent(const sp<audioflinger::SyncEvent>& event);
-    virtual     bool        isValidSyncEvent(const sp<audioflinger::SyncEvent>& event) const;
+    status_t setSyncEvent(const sp<audioflinger::SyncEvent>& event) final;
+    bool isValidSyncEvent(const sp<audioflinger::SyncEvent>& event) const final;
 
-    virtual     void        checkSilentMode_l() {}
-    virtual     void        processVolume_l() {}
+    virtual void checkSilentMode_l() {} // cannot be const (RecordThread)
+    virtual void processVolume_l() {}
                 void        checkInvalidTracks_l();
 
-    virtual     audio_stream_type_t streamType() { return AUDIO_STREAM_DEFAULT; }
-
-    virtual     void        invalidateTracks(audio_stream_type_t streamType __unused) {}
-    virtual     void        invalidateTracks(std::set<audio_port_handle_t>& portIds __unused) {}
+    // Not in ThreadBase
+    virtual audio_stream_type_t streamType() const { return AUDIO_STREAM_DEFAULT; }
+    virtual void invalidateTracks(audio_stream_type_t /* streamType */) {}
+    void invalidateTracks(std::set<audio_port_handle_t>& /* portIds */) override {}
 
                 // Sets the UID records silence
-    virtual     void        setRecordSilenced(audio_port_handle_t portId __unused,
-                                              bool silenced __unused) {}
+    void setRecordSilenced(
+            audio_port_handle_t /* portId */, bool /* silenced */) override {}
 
-    virtual     bool        isStreamInitialized() { return false; }
+    bool isStreamInitialized() const override { return false; }
 
                 void        setClientSilencedState_l(audio_port_handle_t portId, bool silenced) {
                                 mClientSilencedStates[portId] = silenced;
@@ -2198,8 +2123,8 @@
                             }
 
  protected:
-                void        dumpInternals_l(int fd, const Vector<String16>& args) override;
-                void        dumpTracks_l(int fd, const Vector<String16>& args) override;
+    void dumpInternals_l(int fd, const Vector<String16>& args) override;
+    void dumpTracks_l(int fd, const Vector<String16>& args) final;
 
                 /**
                  * @brief mDeviceId  current device port unique identifier
@@ -2222,56 +2147,59 @@
      static     constexpr int32_t       kMaxNoCallbackWarnings = 5;
 };
 
-class MmapPlaybackThread : public MmapThread, public VolumeInterface
-{
-
+class MmapPlaybackThread : public MmapThread, public IAfMmapPlaybackThread,
+        public virtual VolumeInterface {
 public:
     MmapPlaybackThread(const sp<AudioFlinger>& audioFlinger, audio_io_handle_t id,
                        AudioHwDevice *hwDev, AudioStreamOut *output, bool systemReady);
-    virtual     ~MmapPlaybackThread() {}
 
-    virtual     void        configure(const audio_attributes_t *attr,
+    sp<IAfMmapPlaybackThread> asIAfMmapPlaybackThread() final {
+        return sp<IAfMmapPlaybackThread>::fromExisting(this);
+    }
+
+    void configure(const audio_attributes_t* attr,
                                       audio_stream_type_t streamType,
                                       audio_session_t sessionId,
                                       const sp<MmapStreamCallback>& callback,
                                       audio_port_handle_t deviceId,
-                                      audio_port_handle_t portId);
+                                      audio_port_handle_t portId) final;
 
-                AudioStreamOut* clearOutput();
+    AudioStreamOut* clearOutput() final;
 
                 // VolumeInterface
-    virtual     void        setMasterVolume(float value);
-    virtual     void        setMasterMute(bool muted);
-    virtual     void        setStreamVolume(audio_stream_type_t stream, float value);
-    virtual     void        setStreamMute(audio_stream_type_t stream, bool muted);
-    virtual     float       streamVolume(audio_stream_type_t stream) const;
+    void setMasterVolume(float value) final;
+    void setMasterBalance(float /* value */) final {}  // Needs implementation?
+    void setMasterMute(bool muted) final;
+    void setStreamVolume(audio_stream_type_t stream, float value) final;
+    void setStreamMute(audio_stream_type_t stream, bool muted) final;
+    float streamVolume(audio_stream_type_t stream) const final;
 
                 void        setMasterMute_l(bool muted) { mMasterMute = muted; }
 
-    virtual     void        invalidateTracks(audio_stream_type_t streamType);
-                void        invalidateTracks(std::set<audio_port_handle_t>& portIds) override;
+    void invalidateTracks(audio_stream_type_t streamType) final;
+    void invalidateTracks(std::set<audio_port_handle_t>& portIds) final;
 
-    virtual     audio_stream_type_t streamType() { return mStreamType; }
-    virtual     void        checkSilentMode_l();
-                void        processVolume_l() override;
+    audio_stream_type_t streamType() const final { return mStreamType; }
+    void checkSilentMode_l() final;
+    void processVolume_l() final;
 
-                MetadataUpdate        updateMetadata_l() override;
+    MetadataUpdate updateMetadata_l() final;
 
-    virtual     void        toAudioPortConfig(struct audio_port_config *config);
+    void toAudioPortConfig(struct audio_port_config* config) final;
 
-                status_t    getExternalPosition(uint64_t *position, int64_t *timeNanos) override;
+    status_t getExternalPosition(uint64_t* position, int64_t* timeNanos) const final;
 
-    virtual     bool        isStreamInitialized() {
+    bool isStreamInitialized() const final {
                                 return !(mOutput == nullptr || mOutput->stream == nullptr);
                             }
 
-                status_t    reportData(const void* buffer, size_t frameCount) override;
+    status_t reportData(const void* buffer, size_t frameCount) final;
 
-                void startMelComputation_l(const sp<audio_utils::MelProcessor>& processor) override;
-                void stopMelComputation_l() override;
+    void startMelComputation_l(const sp<audio_utils::MelProcessor>& processor) final;
+    void stopMelComputation_l() final;
 
 protected:
-                void        dumpInternals_l(int fd, const Vector<String16>& args) override;
+    void dumpInternals_l(int fd, const Vector<String16>& args) final;
                 float       streamVolume_l() const {
                     return mStreamTypes[mStreamType].volume;
                 }
@@ -2288,28 +2216,29 @@
                 mediautils::atomic_sp<audio_utils::MelProcessor> mMelProcessor;
 };
 
-class MmapCaptureThread : public MmapThread
+class MmapCaptureThread : public MmapThread, public IAfMmapCaptureThread
 {
-
 public:
     MmapCaptureThread(const sp<AudioFlinger>& audioFlinger, audio_io_handle_t id,
                       AudioHwDevice *hwDev, AudioStreamIn *input, bool systemReady);
-    virtual     ~MmapCaptureThread() {}
 
-                AudioStreamIn* clearInput();
+    sp<IAfMmapCaptureThread> asIAfMmapCaptureThread() final {
+        return sp<IAfMmapCaptureThread>::fromExisting(this);
+    }
 
-                status_t       exitStandby_l() REQUIRES(mLock) override;
+    AudioStreamIn* clearInput() final;
 
-                MetadataUpdate           updateMetadata_l() override;
-                void           processVolume_l() override;
-                void           setRecordSilenced(audio_port_handle_t portId,
-                                                 bool silenced) override;
+    status_t exitStandby_l() REQUIRES(mLock) final;
 
-    virtual     void           toAudioPortConfig(struct audio_port_config *config);
+    MetadataUpdate updateMetadata_l() final;
+    void processVolume_l() final;
+    void setRecordSilenced(audio_port_handle_t portId, bool silenced) final;
 
-                status_t       getExternalPosition(uint64_t *position, int64_t *timeNanos) override;
+    void toAudioPortConfig(struct audio_port_config* config) final;
 
-    virtual     bool           isStreamInitialized() {
+    status_t getExternalPosition(uint64_t* position, int64_t* timeNanos) const final;
+
+    bool isStreamInitialized() const final {
                                    return !(mInput == nullptr || mInput->stream == nullptr);
                                }
 
@@ -2324,8 +2253,8 @@
                      audio_io_handle_t id, bool systemReady);
 
 protected:
-    mixer_state prepareTracks_l(Vector<sp<IAfTrack>>* tracksToRemove) override;
-    void threadLoop_mix() override;
+    mixer_state prepareTracks_l(Vector<sp<IAfTrack>>* tracksToRemove) final;
+    void threadLoop_mix() final;
 
 private:
     bool mIsBitPerfect;
@@ -2333,4 +2262,4 @@
     float mVolumeRight = 0.f;
 };
 
-private:
\ No newline at end of file
+} // namespace android
diff --git a/services/audioflinger/TrackBase.h b/services/audioflinger/TrackBase.h
index 8f31468..194a515 100644
--- a/services/audioflinger/TrackBase.h
+++ b/services/audioflinger/TrackBase.h
@@ -22,7 +22,7 @@
 // base for record and playback
 class TrackBase : public ExtendedAudioBufferProvider, public virtual IAfTrackBase {
 public:
-                        TrackBase(AudioFlinger::ThreadBase* thread,
+    TrackBase(IAfThreadBase* thread,
                                 const sp<Client>& client,
                                 const audio_attributes_t& mAttr,
                                 uint32_t sampleRate,
@@ -69,8 +69,7 @@
     bool isSpatialized() const override { return false; }
     bool isBitPerfect() const override { return false; }
 
-    // TODO(b/288339104) type
-    wp<Thread> thread() const final { return mThread; }
+    wp<IAfThreadBase> thread() const final { return mThread; }
 
     const sp<ServerProxy>& serverProxy() const final { return mServerProxy; }
 
@@ -322,7 +321,7 @@
                                     // true for Track, false for RecordTrack,
                                     // this could be a track type if needed later
 
-    const wp<AudioFlinger::ThreadBase> mThread;
+    const wp<IAfThreadBase> mThread;
     const alloc_type     mAllocType;
     /*const*/ sp<Client> mClient;   // see explanation at ~TrackBase() why not const
     sp<IMemory>         mCblkMemory;
@@ -392,7 +391,7 @@
 {
 public:
                         PatchTrackBase(const sp<ClientProxy>& proxy,
-                                       const AudioFlinger::ThreadBase& thread,
+                                       IAfThreadBase* thread,
                                        const Timeout& timeout);
             void setPeerTimeout(std::chrono::nanoseconds timeout) final;
             void setPeerProxy(const sp<IAfPatchTrackBase>& proxy, bool holdReference) final {
diff --git a/services/audioflinger/Tracks.cpp b/services/audioflinger/Tracks.cpp
index 6722dc3..9169783 100644
--- a/services/audioflinger/Tracks.cpp
+++ b/services/audioflinger/Tracks.cpp
@@ -81,7 +81,7 @@
 
 // TrackBase constructor must be called with AudioFlinger::mLock held
 TrackBase::TrackBase(
-            AudioFlinger::ThreadBase *thread,
+        IAfThreadBase *thread,
             const sp<Client>& client,
             const audio_attributes_t& attr,
             uint32_t sampleRate,
@@ -315,15 +315,15 @@
 }
 
 PatchTrackBase::PatchTrackBase(const sp<ClientProxy>& proxy,
-        const AudioFlinger::ThreadBase& thread, const Timeout& timeout)
+        IAfThreadBase* thread, const Timeout& timeout)
     : mProxy(proxy)
 {
     if (timeout) {
         setPeerTimeout(*timeout);
     } else {
         // Double buffer mixer
-        uint64_t mixBufferNs = ((uint64_t)2 * thread.frameCount() * 1000000000) /
-                                              thread.sampleRate();
+        uint64_t mixBufferNs = ((uint64_t)2 * thread->frameCount() * 1000000000) /
+                                              thread->sampleRate();
         setPeerTimeout(std::chrono::nanoseconds{mixBufferNs});
     }
 }
@@ -388,7 +388,6 @@
     : BnAudioTrack(),
       mTrack(track)
 {
-    // TODO(b/288339104) binder thread priority change not needed.
     setMinSchedulerPolicy(SCHED_NORMAL, ANDROID_PRIORITY_AUDIO);
 }
 
@@ -559,11 +558,12 @@
 
 // static
 sp<OpPlayAudioMonitor> OpPlayAudioMonitor::createIfNeeded(
+            IAfThreadBase* thread,
             const AttributionSourceState& attributionSource, const audio_attributes_t& attr, int id,
             audio_stream_type_t streamType)
 {
-    Vector <String16> packages;
-    uid_t uid = VALUE_OR_FATAL(aidl2legacy_int32_t_uid_t(attributionSource.uid));
+    Vector<String16> packages;
+    const uid_t uid = VALUE_OR_FATAL(aidl2legacy_int32_t_uid_t(attributionSource.uid));
     getPackagesForUid(uid, packages);
     if (isServiceUid(uid)) {
         if (packages.isEmpty()) {
@@ -585,15 +585,20 @@
             id, attr.flags);
         return nullptr;
     }
-    return new OpPlayAudioMonitor(attributionSource, attr.usage, id);
+    return sp<OpPlayAudioMonitor>::make(thread, attributionSource, attr.usage, id, uid);
 }
 
-OpPlayAudioMonitor::OpPlayAudioMonitor(
-        const AttributionSourceState& attributionSource, audio_usage_t usage, int id)
-        : mHasOpPlayAudio(true), mAttributionSource(attributionSource), mUsage((int32_t) usage),
-        mId(id)
-{
-}
+OpPlayAudioMonitor::OpPlayAudioMonitor(IAfThreadBase* thread,
+                                       const AttributionSourceState& attributionSource,
+                                       audio_usage_t usage, int id, uid_t uid)
+    : mThread(wp<IAfThreadBase>::fromExisting(thread)),
+      mHasOpPlayAudio(true),
+      mAttributionSource(attributionSource),
+      mUsage((int32_t)usage),
+      mId(id),
+      mUid(uid),
+      mPackageName(VALUE_OR_FATAL(aidl2legacy_string_view_String16(
+                  attributionSource.packageName.value_or("")))) {}
 
 OpPlayAudioMonitor::~OpPlayAudioMonitor()
 {
@@ -609,9 +614,7 @@
     if (mAttributionSource.packageName.has_value()) {
         mOpCallback = new PlayAudioOpCallback(this);
         mAppOpsManager.startWatchingMode(AppOpsManager::OP_PLAY_AUDIO,
-            VALUE_OR_FATAL(aidl2legacy_string_view_String16(
-            mAttributionSource.packageName.value_or("")))
-            , mOpCallback);
+                mPackageName, mOpCallback);
     }
 }
 
@@ -624,16 +627,20 @@
 // - not called from PlayAudioOpCallback because the callback is not installed in this case
 void OpPlayAudioMonitor::checkPlayAudioForUsage()
 {
-    if (!mAttributionSource.packageName.has_value()) {
-        mHasOpPlayAudio.store(false);
-    } else {
-        uid_t uid = VALUE_OR_FATAL(aidl2legacy_int32_t_uid_t(mAttributionSource.uid));
-        String16 packageName = VALUE_OR_FATAL(
-            aidl2legacy_string_view_String16(mAttributionSource.packageName.value_or("")));
-        bool hasIt = mAppOpsManager.checkAudioOpNoThrow(AppOpsManager::OP_PLAY_AUDIO,
-                    mUsage, uid, packageName) == AppOpsManager::MODE_ALLOWED;
-        ALOGD("OpPlayAudio: track:%d usage:%d %smuted", mId, mUsage, hasIt ? "not " : "");
-        mHasOpPlayAudio.store(hasIt);
+    const bool hasAppOps = mAttributionSource.packageName.has_value()
+        && mAppOpsManager.checkAudioOpNoThrow(
+                AppOpsManager::OP_PLAY_AUDIO, mUsage, mUid, mPackageName) ==
+                        AppOpsManager::MODE_ALLOWED;
+
+    bool shouldChange = !hasAppOps;  // check if we need to update.
+    if (mHasOpPlayAudio.compare_exchange_strong(shouldChange, hasAppOps)) {
+        ALOGD("OpPlayAudio: track:%d usage:%d %smuted", mId, mUsage, hasAppOps ? "not " : "");
+        auto thread = mThread.promote();
+        if (thread != nullptr && thread->type() == IAfThreadBase::OFFLOAD) {
+            // Wake up Thread if offloaded, otherwise it may be several seconds for update.
+            Mutex::Autolock _l(thread->mutex());
+            thread->broadcast_l();
+        }
     }
 }
 
@@ -667,8 +674,8 @@
 #define LOG_TAG "AF::Track"
 
 /* static */
-sp<IAfTrack> IAfTrack::create( // TODO(b/288339104) void*
-        void * /* AudioFlinger::PlaybackThread */ thread,
+sp<IAfTrack> IAfTrack::create(
+        IAfPlaybackThread* thread,
         const sp<Client>& client,
         audio_stream_type_t streamType,
         const audio_attributes_t& attr,
@@ -691,7 +698,7 @@
         float speed,
         bool isSpatialized,
         bool isBitPerfect) {
-    return sp<Track>::make(reinterpret_cast<AudioFlinger::PlaybackThread*>(thread),
+    return sp<Track>::make(thread,
             client,
             streamType,
             attr,
@@ -716,7 +723,7 @@
 
 // Track constructor must be called with AudioFlinger::mLock and ThreadBase::mLock held
 Track::Track(
-            AudioFlinger::PlaybackThread *thread,
+        IAfPlaybackThread* thread,
             const sp<Client>& client,
             audio_stream_type_t streamType,
             const audio_attributes_t& attr,
@@ -759,7 +766,7 @@
     mAuxEffectId(0), mHasVolumeController(false),
     mFrameMap(16 /* sink-frame-to-track-frame map memory */),
     mVolumeHandler(new media::VolumeHandler(sampleRate)),
-    mOpPlayAudioMonitor(OpPlayAudioMonitor::createIfNeeded(attributionSource, attr, id(),
+    mOpPlayAudioMonitor(OpPlayAudioMonitor::createIfNeeded(thread, attributionSource, attr, id(),
         streamType)),
     // mSinkTimestamp
     mFastIndex(-1),
@@ -807,15 +814,15 @@
         // race with setSyncEvent(). However, if we call it, we cannot properly start
         // static fast tracks (SoundPool) immediately after stopping.
         //mAudioTrackServerProxy->framesReadyIsCalledByMultipleThreads();
-        ALOG_ASSERT(thread->mFastTrackAvailMask != 0);
-        int i = __builtin_ctz(thread->mFastTrackAvailMask);
+        ALOG_ASSERT(thread->fastTrackAvailMask_l() != 0);
+        const int i = __builtin_ctz(thread->fastTrackAvailMask_l());
         ALOG_ASSERT(0 < i && i < (int)FastMixerState::sMaxFastTracks);
         // FIXME This is too eager.  We allocate a fast track index before the
         //       fast track becomes active.  Since fast tracks are a scarce resource,
         //       this means we are potentially denying other more important fast tracks from
         //       being created.  It would be better to allocate the index dynamically.
         mFastIndex = i;
-        thread->mFastTrackAvailMask &= ~(1 << i);
+        thread->fastTrackAvailMask_l() &= ~(1 << i);
     }
 
     mServerLatencySupported = checkServerLatencySupported(format, flags);
@@ -875,10 +882,10 @@
     sp<Track> keep(this);
     { // scope for mLock
         bool wasActive = false;
-        sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+        const sp<IAfThreadBase> thread = mThread.promote();
         if (thread != 0) {
-            Mutex::Autolock _l(thread->mLock);
-            auto* const playbackThread = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
+            Mutex::Autolock _l(thread->mutex());
+            auto* const playbackThread = thread->asIAfPlaybackThread().get();
             wasActive = playbackThread->destroyTrack_l(this);
             forEachTeePatchTrack_l([](const auto& patchTrack) { patchTrack->destroy(); });
         }
@@ -1154,19 +1161,19 @@
     ALOGV("%s(%d): calling pid %d session %d",
             __func__, mId, IPCThreadState::self()->getCallingPid(), mSessionId);
 
-    sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+    const sp<IAfThreadBase> thread = mThread.promote();
     if (thread != 0) {
         if (isOffloaded()) {
-            Mutex::Autolock _laf(thread->mAudioFlinger->mLock);
-            Mutex::Autolock _lth(thread->mLock);
+            Mutex::Autolock _laf(thread->audioFlinger()->mLock);
+            Mutex::Autolock _lth(thread->mutex());
             sp<IAfEffectChain> ec = thread->getEffectChain_l(mSessionId);
-            if (thread->mAudioFlinger->isNonOffloadableGlobalEffectEnabled_l() ||
+            if (thread->audioFlinger()->isNonOffloadableGlobalEffectEnabled_l() ||
                     (ec != 0 && ec->isNonOffloadableEnabled())) {
                 invalidate();
                 return PERMISSION_DENIED;
             }
         }
-        Mutex::Autolock _lth(thread->mLock);
+        Mutex::Autolock _lth(thread->mutex());
         track_state state = mState;
         // here the track could be either new, or restarted
         // in both cases "unstop" the track
@@ -1198,7 +1205,7 @@
                     __func__, mId, (int)mThreadIoHandle);
         }
 
-        auto* const playbackThread = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
+        auto* const playbackThread = thread->asIAfPlaybackThread().get();
 
         // states to reset position info for pcm tracks
         if (audio_is_linear_pcm(mFormat)
@@ -1266,7 +1273,7 @@
     }
     if (status == NO_ERROR) {
         // send format to AudioManager for playback activity monitoring
-        sp<IAudioManager> audioManager = thread->mAudioFlinger->getOrCreateAudioManager();
+        const sp<IAudioManager> audioManager = thread->audioFlinger()->getOrCreateAudioManager();
         if (audioManager && mPortId != AUDIO_PORT_HANDLE_NONE) {
             std::unique_ptr<os::PersistableBundle> bundle =
                     std::make_unique<os::PersistableBundle>();
@@ -1288,14 +1295,14 @@
 void Track::stop()
 {
     ALOGV("%s(%d): calling pid %d", __func__, mId, IPCThreadState::self()->getCallingPid());
-    sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+    const sp<IAfThreadBase> thread = mThread.promote();
     if (thread != 0) {
-        Mutex::Autolock _l(thread->mLock);
+        Mutex::Autolock _l(thread->mutex());
         track_state state = mState;
         if (state == RESUMING || state == ACTIVE || state == PAUSING || state == PAUSED) {
             // If the track is not active (PAUSED and buffers full), flush buffers
-            auto* const playbackThread = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
-            if (playbackThread->mActiveTracks.indexOf(this) < 0) {
+            auto* const playbackThread = thread->asIAfPlaybackThread().get();
+            if (!playbackThread->isTrackActive(this)) {
                 reset();
                 mState = STOPPED;
             } else if (!isFastTrack() && !isOffloaded() && !isDirect()) {
@@ -1307,7 +1314,7 @@
                 // move to STOPPING_2 when drain completes and then STOPPED
                 mState = STOPPING_1;
                 if (isOffloaded()) {
-                    mRetryCount = AudioFlinger::PlaybackThread::kMaxTrackStopRetriesOffload;
+                    mRetryCount = IAfPlaybackThread::kMaxTrackStopRetriesOffload;
                 }
             }
             playbackThread->broadcast_l();
@@ -1321,10 +1328,10 @@
 void Track::pause()
 {
     ALOGV("%s(%d): calling pid %d", __func__, mId, IPCThreadState::self()->getCallingPid());
-    sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+    const sp<IAfThreadBase> thread = mThread.promote();
     if (thread != 0) {
-        Mutex::Autolock _l(thread->mLock);
-        auto* const playbackThread = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
+        Mutex::Autolock _l(thread->mutex());
+        auto* const playbackThread = thread->asIAfPlaybackThread().get();
         switch (mState) {
         case STOPPING_1:
         case STOPPING_2:
@@ -1358,15 +1365,15 @@
 void Track::flush()
 {
     ALOGV("%s(%d)", __func__, mId);
-    sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+    const sp<IAfThreadBase> thread = mThread.promote();
     if (thread != 0) {
-        Mutex::Autolock _l(thread->mLock);
-        auto* const playbackThread = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
+        Mutex::Autolock _l(thread->mutex());
+        auto* const playbackThread = thread->asIAfPlaybackThread().get();
 
         // Flush the ring buffer now if the track is not active in the PlaybackThread.
         // Otherwise the flush would not be done until the track is resumed.
         // Requires FastTrack removal be BLOCK_UNTIL_ACKED
-        if (playbackThread->mActiveTracks.indexOf(this) < 0) {
+        if (!playbackThread->isTrackActive(this)) {
             (void)mServerProxy->flushBufferIfNeeded();
         }
 
@@ -1405,7 +1412,7 @@
             if (isDirect()) {
                 mFlushHwPending = true;
             }
-            if (playbackThread->mActiveTracks.indexOf(this) < 0) {
+            if (!playbackThread->isTrackActive(this)) {
                 reset();
             }
         }
@@ -1456,12 +1463,12 @@
 
 status_t Track::setParameters(const String8& keyValuePairs)
 {
-    sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+    const sp<IAfThreadBase> thread = mThread.promote();
     if (thread == 0) {
         ALOGE("%s(%d): thread is dead", __func__, mId);
         return FAILED_TRANSACTION;
-    } else if ((thread->type() == AudioFlinger::ThreadBase::DIRECT) ||
-                    (thread->type() == AudioFlinger::ThreadBase::OFFLOAD)) {
+    } else if (thread->type() == IAfThreadBase::DIRECT
+            || thread->type() == IAfThreadBase::OFFLOAD) {
         return thread->setParameters(keyValuePairs);
     } else {
         return PERMISSION_DENIED;
@@ -1470,13 +1477,13 @@
 
 status_t Track::selectPresentation(int presentationId,
         int programId) {
-    sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+    const sp<IAfThreadBase> thread = mThread.promote();
     if (thread == 0) {
         ALOGE("thread is dead");
         return FAILED_TRANSACTION;
-    } else if ((thread->type() == AudioFlinger::ThreadBase::DIRECT)
-            || (thread->type() == AudioFlinger::ThreadBase::OFFLOAD)) {
-        auto directOutputThread = static_cast<AudioFlinger::DirectOutputThread*>(thread.get());
+    } else if (thread->type() == IAfThreadBase::DIRECT
+            || thread->type() == IAfThreadBase::OFFLOAD) {
+        auto directOutputThread = thread->asIAfDirectOutputThread().get();
         return directOutputThread->selectPresentation(presentationId, programId);
     }
     return INVALID_OPERATION;
@@ -1490,9 +1497,9 @@
 
     if (isOffloadedOrDirect()) {
         // Signal thread to fetch new volume.
-        sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+        const sp<IAfThreadBase> thread = mThread.promote();
         if (thread != 0) {
-            Mutex::Autolock _l(thread->mLock);
+            Mutex::Autolock _l(thread->mutex());
             thread->broadcast_l();
         }
     }
@@ -1607,7 +1614,7 @@
     }
 }
 
-void Track::setTeePatchesToUpdate_l(AudioFlinger::TeePatches teePatchesToUpdate) {
+void Track::setTeePatchesToUpdate_l(TeePatches teePatchesToUpdate) {
     ALOGW_IF(mTeePatchesToUpdate.has_value(),
              "%s, existing tee patches to update will be ignored", __func__);
     mTeePatchesToUpdate = std::move(teePatchesToUpdate);
@@ -1651,26 +1658,26 @@
     if (!isOffloaded() && !isDirect()) {
         return INVALID_OPERATION; // normal tracks handled through SSQ
     }
-    sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+    const sp<IAfThreadBase> thread = mThread.promote();
     if (thread == 0) {
         return INVALID_OPERATION;
     }
 
-    Mutex::Autolock _l(thread->mLock);
-    auto* const playbackThread = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
+    Mutex::Autolock _l(thread->mutex());
+    auto* const playbackThread = thread->asIAfPlaybackThread().get();
     return playbackThread->getTimestamp_l(timestamp);
 }
 
 status_t Track::attachAuxEffect(int EffectId)
 {
-    sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+    const sp<IAfThreadBase> thread = mThread.promote();
     if (thread == nullptr) {
         return DEAD_OBJECT;
     }
 
-    auto dstThread = sp<AudioFlinger::PlaybackThread>::cast(thread);
+    auto dstThread = thread->asIAfPlaybackThread();
     // srcThread is initialized by call to moveAuxEffectToIo()
-    sp<AudioFlinger::PlaybackThread> srcThread;
+    sp<IAfPlaybackThread> srcThread;
     sp<AudioFlinger> af = mClient->audioFlinger();
     status_t status = af->moveAuxEffectToIo(EffectId, dstThread, &srcThread);
 
@@ -1856,10 +1863,10 @@
 
 void Track::signal()
 {
-    sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+    const sp<IAfThreadBase> thread = mThread.promote();
     if (thread != 0) {
-        auto* const t = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
-        Mutex::Autolock _l(t->mLock);
+        auto* const t = thread->asIAfPlaybackThread().get();
+        Mutex::Autolock _l(t->mutex());
         t->broadcast_l();
     }
 }
@@ -1868,11 +1875,11 @@
 {
     status_t status = INVALID_OPERATION;
     if (isOffloadedOrDirect()) {
-        sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+        const sp<IAfThreadBase> thread = mThread.promote();
         if (thread != nullptr) {
-            auto* const t = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
-            Mutex::Autolock _l(t->mLock);
-            status = t->mOutput->stream->getDualMonoMode(mode);
+            auto* const t = thread->asIAfPlaybackThread().get();
+            Mutex::Autolock _l(t->mutex());
+            status = t->getOutput_l()->stream->getDualMonoMode(mode);
             ALOGD_IF((status == NO_ERROR) && (mDualMonoMode != *mode),
                     "%s: mode %d inconsistent", __func__, mDualMonoMode);
         }
@@ -1884,11 +1891,11 @@
 {
     status_t status = INVALID_OPERATION;
     if (isOffloadedOrDirect()) {
-        sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+        const sp<IAfThreadBase> thread = mThread.promote();
         if (thread != nullptr) {
-            auto* const t = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
-            Mutex::Autolock lock(t->mLock);
-            status = t->mOutput->stream->setDualMonoMode(mode);
+            auto* const t = thread->asIAfPlaybackThread().get();
+            Mutex::Autolock lock(t->mutex());
+            status = t->getOutput_l()->stream->setDualMonoMode(mode);
             if (status == NO_ERROR) {
                 mDualMonoMode = mode;
             }
@@ -1901,11 +1908,11 @@
 {
     status_t status = INVALID_OPERATION;
     if (isOffloadedOrDirect()) {
-        sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+        sp<IAfThreadBase> thread = mThread.promote();
         if (thread != nullptr) {
-            auto* const t = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
-            Mutex::Autolock lock(t->mLock);
-            status = t->mOutput->stream->getAudioDescriptionMixLevel(leveldB);
+            auto* const t = thread->asIAfPlaybackThread().get();
+            Mutex::Autolock lock(t->mutex());
+            status = t->getOutput_l()->stream->getAudioDescriptionMixLevel(leveldB);
             ALOGD_IF((status == NO_ERROR) && (mAudioDescriptionMixLevel != *leveldB),
                     "%s: level %.3f inconsistent", __func__, mAudioDescriptionMixLevel);
         }
@@ -1917,11 +1924,11 @@
 {
     status_t status = INVALID_OPERATION;
     if (isOffloadedOrDirect()) {
-        sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+        const sp<IAfThreadBase> thread = mThread.promote();
         if (thread != nullptr) {
-            auto* const t = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
-            Mutex::Autolock lock(t->mLock);
-            status = t->mOutput->stream->setAudioDescriptionMixLevel(leveldB);
+            auto* const t = thread->asIAfPlaybackThread().get();
+            Mutex::Autolock lock(t->mutex());
+            status = t->getOutput_l()->stream->setAudioDescriptionMixLevel(leveldB);
             if (status == NO_ERROR) {
                 mAudioDescriptionMixLevel = leveldB;
             }
@@ -1935,11 +1942,11 @@
 {
     status_t status = INVALID_OPERATION;
     if (isOffloadedOrDirect()) {
-        sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+        const sp<IAfThreadBase> thread = mThread.promote();
         if (thread != nullptr) {
-            auto* const t = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
-            Mutex::Autolock lock(t->mLock);
-            status = t->mOutput->stream->getPlaybackRateParameters(playbackRate);
+            auto* const t = thread->asIAfPlaybackThread().get();
+            Mutex::Autolock lock(t->mutex());
+            status = t->getOutput_l()->stream->getPlaybackRateParameters(playbackRate);
             ALOGD_IF((status == NO_ERROR) &&
                     !isAudioPlaybackRateEqual(mPlaybackRateParameters, *playbackRate),
                     "%s: playbackRate inconsistent", __func__);
@@ -1953,11 +1960,11 @@
 {
     status_t status = INVALID_OPERATION;
     if (isOffloadedOrDirect()) {
-        sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+        const sp<IAfThreadBase> thread = mThread.promote();
         if (thread != nullptr) {
-            auto* const t = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
-            Mutex::Autolock lock(t->mLock);
-            status = t->mOutput->stream->setPlaybackRateParameters(playbackRate);
+            auto* const t = thread->asIAfPlaybackThread().get();
+            Mutex::Autolock lock(t->mutex());
+            status = t->getOutput_l()->stream->setPlaybackRateParameters(playbackRate);
             if (status == NO_ERROR) {
                 mPlaybackRateParameters = playbackRate;
             }
@@ -2076,13 +2083,13 @@
 }
 
 bool Track::AudioVibrationController::setMute(bool muted) {
-    sp<AudioFlinger::ThreadBase> thread = mTrack->mThread.promote();
+    const sp<IAfThreadBase> thread = mTrack->mThread.promote();
     if (thread != 0) {
         // Lock for updating mHapticPlaybackEnabled.
-        Mutex::Autolock _l(thread->mLock);
-        auto* const playbackThread = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
+        Mutex::Autolock _l(thread->mutex());
+        auto* const playbackThread = thread->asIAfPlaybackThread().get();
         if ((mTrack->channelMask() & AUDIO_CHANNEL_HAPTIC_ALL) != AUDIO_CHANNEL_NONE
-                && playbackThread->mHapticChannelCount > 0) {
+                && playbackThread->hapticChannelCount() > 0) {
             ALOGD("%s, haptic playback was %s for track %d",
                     __func__, muted ? "muted" : "unmuted", mTrack->id());
             mTrack->setHapticPlaybackEnabled(!muted);
@@ -2109,17 +2116,17 @@
 #define LOG_TAG "AF::OutputTrack"
 
 /* static */
-sp<IAfOutputTrack> IAfOutputTrack::create(  // TODO(b/288339104) void*
-        void* /* AudioFlinger::PlaybackThread */ playbackThread,
-        void* /* AudioFlinger::DuplicatingThread */ sourceThread,
+sp<IAfOutputTrack> IAfOutputTrack::create(
+        IAfPlaybackThread* playbackThread,
+        IAfDuplicatingThread* sourceThread,
         uint32_t sampleRate,
         audio_format_t format,
         audio_channel_mask_t channelMask,
         size_t frameCount,
         const AttributionSourceState& attributionSource) {
     return sp<OutputTrack>::make(
-            reinterpret_cast<AudioFlinger::PlaybackThread*>(playbackThread),
-            reinterpret_cast<AudioFlinger::DuplicatingThread*>(sourceThread),
+            playbackThread,
+            sourceThread,
             sampleRate,
             format,
             channelMask,
@@ -2128,8 +2135,8 @@
 }
 
 OutputTrack::OutputTrack(
-            AudioFlinger::PlaybackThread *playbackThread,
-            AudioFlinger::DuplicatingThread *sourceThread,
+            IAfPlaybackThread* playbackThread,
+            IAfDuplicatingThread* sourceThread,
             uint32_t sampleRate,
             audio_format_t format,
             audio_channel_mask_t channelMask,
@@ -2146,7 +2153,7 @@
 
     if (mCblk != NULL) {
         mOutBuffer.frameCount = 0;
-        playbackThread->mTracks.add(this);
+        playbackThread->addOutputTrack_l(this);
         ALOGV("%s(): mCblk %p, mBuffer %p, "
                 "frameCount %zu, mChannelMask 0x%08x",
                 __func__, mCblk, mBuffer,
@@ -2194,8 +2201,8 @@
 ssize_t OutputTrack::write(void* data, uint32_t frames)
 {
     if (!mActive && frames != 0) {
-        sp<AudioFlinger::ThreadBase> thread = mThread.promote();
-        if (thread != nullptr && thread->standby()) {
+        const sp<IAfThreadBase> thread = mThread.promote();
+        if (thread != nullptr && thread->inStandby()) {
             // preload one silent buffer to trigger mixer on start()
             ClientProxy::Buffer buf { .mFrameCount = mClientProxy->getStartThresholdInFrames() };
             status_t status = mClientProxy->obtainBuffer(&buf);
@@ -2213,7 +2220,7 @@
             // If another OutputTrack has already started it can underrun but this is OK
             // as only silence has been played so far and the retry count is very high on
             // OutputTrack.
-            auto* const pt = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
+            auto* const pt = thread->asIAfPlaybackThread().get();
             if (!pt->waitForHalStart()) {
                 ALOGW("%s(%d): timeout waiting for thread to exit standby", __func__, mId);
                 stop();
@@ -2302,8 +2309,8 @@
 
     // If we could not write all frames, allocate a buffer and queue it for next time.
     if (inBuffer.frameCount) {
-        sp<AudioFlinger::ThreadBase> thread = mThread.promote();
-        if (thread != 0 && !thread->standby()) {
+        const sp<IAfThreadBase> thread = mThread.promote();
+        if (thread != nullptr && !thread->inStandby()) {
             queueBuffer(inBuffer);
         }
     }
@@ -2395,7 +2402,7 @@
 
 /* static */
 sp<IAfPatchTrack> IAfPatchTrack::create(
-        void* /* PlaybackThread */ playbackThread, // TODO(b/288339104)
+        IAfPlaybackThread* playbackThread,
         audio_stream_type_t streamType,
         uint32_t sampleRate,
         audio_channel_mask_t channelMask,
@@ -2411,7 +2418,7 @@
                                          *  even if it might glitch. */)
 {
     return sp<PatchTrack>::make(
-            reinterpret_cast<AudioFlinger::PlaybackThread*>(playbackThread),
+            playbackThread,
             streamType,
             sampleRate,
             channelMask,
@@ -2424,7 +2431,7 @@
             frameCountToBeReady);
 }
 
-PatchTrack::PatchTrack(AudioFlinger::PlaybackThread *playbackThread,
+PatchTrack::PatchTrack(IAfPlaybackThread* playbackThread,
                                                      audio_stream_type_t streamType,
                                                      uint32_t sampleRate,
                                                      audio_channel_mask_t channelMask,
@@ -2441,8 +2448,9 @@
               buffer, bufferSize, nullptr /* sharedBuffer */,
               AUDIO_SESSION_NONE, getpid(), audioServerAttributionSource(getpid()), flags,
               TYPE_PATCH, AUDIO_PORT_HANDLE_NONE, frameCountToBeReady),
-        PatchTrackBase(new ClientProxy(mCblk, mBuffer, frameCount, mFrameSize, true, true),
-                       *playbackThread, timeout)
+        PatchTrackBase(mCblk ? new ClientProxy(mCblk, mBuffer, frameCount, mFrameSize, true, true)
+                        : nullptr,
+                       playbackThread, timeout)
 {
     ALOGV("%s(%d): sampleRate %d mPeerTimeout %d.%03d sec",
                                       __func__, mId, sampleRate,
@@ -2541,9 +2549,9 @@
     if (mFillingStatus == FS_ACTIVE
             && audio_is_linear_pcm(mFormat)
             && !isOffloadedOrDirect()) {
-        if (sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+        if (const sp<IAfThreadBase> thread = mThread.promote();
             thread != 0) {
-            auto* const playbackThread = static_cast<AudioFlinger::PlaybackThread*>(thread.get());
+            auto* const playbackThread = thread->asIAfPlaybackThread().get();
             const size_t frameCount = playbackThread->frameCount() * sampleRate()
                     / playbackThread->sampleRate();
             if (framesReady() < frameCount) {
@@ -2603,7 +2611,6 @@
     : BnAudioRecord(),
     mRecordTrack(recordTrack)
 {
-    // TODO(b/288339104) binder thread priority change not needed.
     setMinSchedulerPolicy(SCHED_NORMAL, ANDROID_PRIORITY_AUDIO);
 }
 
@@ -2658,8 +2665,8 @@
 #define LOG_TAG "AF::RecordTrack"
 
 
-/* static */ // TODO(b/288339104)
-sp<IAfRecordTrack> IAfRecordTrack::create(void* /*AudioFlinger::RecordThread */ thread,
+/* static */
+sp<IAfRecordTrack> IAfRecordTrack::create(IAfRecordThread* thread,
         const sp<Client>& client,
         const audio_attributes_t& attr,
         uint32_t sampleRate,
@@ -2677,7 +2684,7 @@
         int32_t startFrames)
 {
     return sp<RecordTrack>::make(
-        reinterpret_cast<AudioFlinger::RecordThread*>(thread),
+        thread,
         client,
         attr,
         sampleRate,
@@ -2697,7 +2704,7 @@
 
 // RecordTrack constructor must be called with AudioFlinger::mLock and ThreadBase::mLock held
 RecordTrack::RecordTrack(
-            AudioFlinger::RecordThread* thread,
+            IAfRecordThread* thread,
             const sp<Client>& client,
             const audio_attributes_t& attr,
             uint32_t sampleRate,
@@ -2736,7 +2743,7 @@
 
     if (!isDirect()) {
         mRecordBufferConverter = new RecordBufferConverter(
-                thread->mChannelMask, thread->mFormat, thread->mSampleRate,
+                thread->channelMask(), thread->format(), thread->sampleRate(),
                 channelMask, format, sampleRate);
         // Check if the RecordBufferConverter construction was successful.
         // If not, don't continue with construction.
@@ -2756,8 +2763,8 @@
     mResamplerBufferProvider = new ResamplerBufferProvider(this);
 
     if (flags & AUDIO_INPUT_FLAG_FAST) {
-        ALOG_ASSERT(thread->mFastTrackAvail);
-        thread->mFastTrackAvail = false;
+        ALOG_ASSERT(thread->fastTrackAvailable());
+        thread->setFastTrackAvailable(false);
     } else {
         // TODO: only Normal Record has timestamps (Fast Record does not).
         mServerLatencySupported = checkServerLatencySupported(mFormat, flags);
@@ -2806,9 +2813,9 @@
 status_t RecordTrack::start(AudioSystem::sync_event_t event,
                                                         audio_session_t triggerSession)
 {
-    sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+    const sp<IAfThreadBase> thread = mThread.promote();
     if (thread != 0) {
-        auto* const recordThread = static_cast<AudioFlinger::RecordThread*>(thread.get());
+        auto* const recordThread = thread->asIAfRecordThread().get();
         return recordThread->start(this, event, triggerSession);
     } else {
         ALOGW("%s track %d: thread was destroyed", __func__, portId());
@@ -2818,9 +2825,9 @@
 
 void RecordTrack::stop()
 {
-    sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+    const sp<IAfThreadBase> thread = mThread.promote();
     if (thread != 0) {
-        auto* const recordThread = static_cast<AudioFlinger::RecordThread*>(thread.get());
+        auto* const recordThread = thread->asIAfRecordThread().get();
         if (recordThread->stop(this) && isExternalTrack()) {
             AudioSystem::stopInput(mPortId);
         }
@@ -2833,10 +2840,10 @@
     sp<RecordTrack> keep(this);
     {
         track_state priorState = mState;
-        sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+        const sp<IAfThreadBase> thread = mThread.promote();
         if (thread != 0) {
-            Mutex::Autolock _l(thread->mLock);
-            auto* const recordThread = static_cast<AudioFlinger::RecordThread*>(thread.get());
+            Mutex::Autolock _l(thread->mutex());
+            auto* const recordThread = thread->asIAfRecordThread().get();
             priorState = mState;
             if (!mSharedAudioPackageName.empty()) {
                 recordThread->resetAudioHistory_l();
@@ -2930,11 +2937,11 @@
         const sp<audioflinger::SyncEvent>& event)
 {
     size_t framesToDrop = 0;
-    sp<AudioFlinger::ThreadBase> threadBase = mThread.promote();
+    const sp<IAfThreadBase> threadBase = mThread.promote();
     if (threadBase != 0) {
         // TODO: use actual buffer filling status instead of 2 buffers when info is available
         // from audio HAL
-        framesToDrop = threadBase->mFrameCount * 2;
+        framesToDrop = threadBase->frameCount() * 2;
     }
 
     mSynchronizedRecordState.onPlaybackFinished(event, framesToDrop);
@@ -2988,9 +2995,9 @@
 status_t RecordTrack::getActiveMicrophones(
         std::vector<media::MicrophoneInfoFw>* activeMicrophones) const
 {
-    sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+    const sp<IAfThreadBase> thread = mThread.promote();
     if (thread != 0) {
-        auto* const recordThread = static_cast<AudioFlinger::RecordThread*>(thread.get());
+        auto* const recordThread = thread->asIAfRecordThread().get();
         return recordThread->getActiveMicrophones(activeMicrophones);
     } else {
         return BAD_VALUE;
@@ -2999,9 +3006,9 @@
 
 status_t RecordTrack::setPreferredMicrophoneDirection(
         audio_microphone_direction_t direction) {
-    sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+    const sp<IAfThreadBase> thread = mThread.promote();
     if (thread != 0) {
-        auto* const recordThread = static_cast<AudioFlinger::RecordThread*>(thread.get());
+        auto* const recordThread = thread->asIAfRecordThread().get();
         return recordThread->setPreferredMicrophoneDirection(direction);
     } else {
         return BAD_VALUE;
@@ -3009,9 +3016,9 @@
 }
 
 status_t RecordTrack::setPreferredMicrophoneFieldDimension(float zoom) {
-    sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+    const sp<IAfThreadBase> thread = mThread.promote();
     if (thread != 0) {
-        auto* const recordThread = static_cast<AudioFlinger::RecordThread*>(thread.get());
+        auto* const recordThread = thread->asIAfRecordThread().get();
         return recordThread->setPreferredMicrophoneFieldDimension(zoom);
     } else {
         return BAD_VALUE;
@@ -3035,9 +3042,9 @@
         return PERMISSION_DENIED;
     }
 
-    sp<AudioFlinger::ThreadBase> thread = mThread.promote();
+    const sp<IAfThreadBase> thread = mThread.promote();
     if (thread != 0) {
-        auto* const recordThread = static_cast<AudioFlinger::RecordThread*>(thread.get());
+        auto* const recordThread = thread->asIAfRecordThread().get();
         status_t status = recordThread->shareAudioHistory(
                 sharedAudioPackageName, mSessionId, sharedAudioStartMs);
         if (status == NO_ERROR) {
@@ -3075,7 +3082,7 @@
 
 /* static */
 sp<IAfPatchRecord> IAfPatchRecord::create(
-        void* /* RecordThread */ recordThread, // TODO(b/288339104)
+        IAfRecordThread* recordThread,
         uint32_t sampleRate,
         audio_channel_mask_t channelMask,
         audio_format_t format,
@@ -3087,7 +3094,7 @@
         audio_source_t source)
 {
     return sp<PatchRecord>::make(
-            reinterpret_cast<AudioFlinger::RecordThread*>(recordThread),
+            recordThread,
             sampleRate,
             channelMask,
             format,
@@ -3099,7 +3106,7 @@
             source);
 }
 
-PatchRecord::PatchRecord(AudioFlinger::RecordThread *recordThread,
+PatchRecord::PatchRecord(IAfRecordThread* recordThread,
                                                      uint32_t sampleRate,
                                                      audio_channel_mask_t channelMask,
                                                      audio_format_t format,
@@ -3114,8 +3121,9 @@
                 sampleRate, format, channelMask, frameCount,
                 buffer, bufferSize, AUDIO_SESSION_NONE, getpid(),
                 audioServerAttributionSource(getpid()), flags, TYPE_PATCH),
-        PatchTrackBase(new ClientProxy(mCblk, mBuffer, frameCount, mFrameSize, false, true),
-                       *recordThread, timeout)
+        PatchTrackBase(mCblk ? new ClientProxy(mCblk, mBuffer, frameCount, mFrameSize, false, true)
+                        : nullptr,
+                       recordThread, timeout)
 {
     ALOGV("%s(%d): sampleRate %d mPeerTimeout %d.%03d sec",
                                       __func__, mId, sampleRate,
@@ -3217,7 +3225,7 @@
 
 /* static */
 sp<IAfPatchRecord> IAfPatchRecord::createPassThru(
-        void* /* RecordThread */ recordThread, // TODO(b/288339104)
+        IAfRecordThread* recordThread,
         uint32_t sampleRate,
         audio_channel_mask_t channelMask,
         audio_format_t format,
@@ -3226,7 +3234,7 @@
         audio_source_t source)
 {
     return sp<PassthruPatchRecord>::make(
-            reinterpret_cast<AudioFlinger::RecordThread*>(recordThread),
+            recordThread,
             sampleRate,
             channelMask,
             format,
@@ -3236,7 +3244,7 @@
 }
 
 PassthruPatchRecord::PassthruPatchRecord(
-        AudioFlinger::RecordThread* recordThread,
+        IAfRecordThread* recordThread,
         uint32_t sampleRate,
         audio_channel_mask_t channelMask,
         audio_format_t format,
@@ -3253,13 +3261,13 @@
 }
 
 sp<StreamInHalInterface> PassthruPatchRecord::obtainStream(
-        sp<AudioFlinger::ThreadBase>* thread)
+        sp<IAfThreadBase>* thread)
 {
     *thread = mThread.promote();
     if (!*thread) return nullptr;
-    auto* const recordThread = static_cast<AudioFlinger::RecordThread*>((*thread).get());
-    Mutex::Autolock _l(recordThread->mLock);
-    return recordThread->mInput ? recordThread->mInput->stream : nullptr;
+    auto* const recordThread = (*thread)->asIAfRecordThread().get();
+    Mutex::Autolock _l(recordThread->mutex());
+    return recordThread->getInput() ? recordThread->getInput()->stream : nullptr;
 }
 
 // PatchProxyBufferProvider methods are called on DirectOutputThread
@@ -3281,7 +3289,7 @@
     const size_t framesToRead = std::min(buffer->mFrameCount, mFrameCount);
     buffer->mFrameCount = 0;
     buffer->mRaw = nullptr;
-    sp<AudioFlinger::ThreadBase> thread;
+    sp<IAfThreadBase> thread;
     sp<StreamInHalInterface> stream = obtainStream(&thread);
     if (!stream) return NO_INIT;  // If there is no stream, RecordThread is not reading.
 
@@ -3368,7 +3376,7 @@
 status_t PassthruPatchRecord::getCapturePosition(
         int64_t* frames, int64_t* time)
 {
-    sp<AudioFlinger::ThreadBase> thread;
+    sp<IAfThreadBase> thread;
     sp<StreamInHalInterface> stream = obtainStream(&thread);
     return stream ? stream->getCapturePosition(frames, time) : NO_INIT;
 }
@@ -3405,7 +3413,7 @@
 #define LOG_TAG "AF::MmapTrack"
 
 /* static */
-sp<IAfMmapTrack> IAfMmapTrack::create(void* /* AudioFlinger::ThreadBase */ thread,
+sp<IAfMmapTrack> IAfMmapTrack::create(IAfThreadBase* thread,
           const audio_attributes_t& attr,
           uint32_t sampleRate,
           audio_format_t format,
@@ -3417,7 +3425,7 @@
           audio_port_handle_t portId)
 {
     return sp<MmapTrack>::make(
-            reinterpret_cast<AudioFlinger::ThreadBase*>(thread),
+            thread,
             attr,
             sampleRate,
             format,
@@ -3429,7 +3437,7 @@
             portId);
 }
 
-MmapTrack::MmapTrack(AudioFlinger::ThreadBase* thread,
+MmapTrack::MmapTrack(IAfThreadBase* thread,
         const audio_attributes_t& attr,
         uint32_t sampleRate,
         audio_format_t format,
diff --git a/services/audioflinger/datapath/AudioStreamIn.h b/services/audioflinger/datapath/AudioStreamIn.h
new file mode 100644
index 0000000..7b3a090
--- /dev/null
+++ b/services/audioflinger/datapath/AudioStreamIn.h
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <media/audiohal/DeviceHalInterface.h>
+#include <media/audiohal/StreamHalInterface.h>
+
+namespace android {
+
+// Abstraction for the Audio Source for the RecordThread (HAL or PassthruPatchRecord).
+struct Source {
+    virtual ~Source() = default;
+    // The following methods have the same signatures as in StreamHalInterface.
+    virtual status_t read(void* buffer, size_t bytes, size_t* read) = 0;
+    virtual status_t getCapturePosition(int64_t* frames, int64_t* time) = 0;
+    virtual status_t standby() = 0;
+};
+
+// AudioStreamIn is immutable, so its fields are const.
+// The methods must not be const to match StreamHalInterface signature.
+
+struct AudioStreamIn : public Source {
+    const AudioHwDevice* const audioHwDev;
+    const sp<StreamInHalInterface> stream;
+    const audio_input_flags_t flags;
+
+    AudioStreamIn(
+            const AudioHwDevice* dev, const sp<StreamInHalInterface>& in,
+            audio_input_flags_t flags)
+        : audioHwDev(dev), stream(in), flags(flags) {}
+
+    status_t read(void* buffer, size_t bytes, size_t* read) final {
+        return stream->read(buffer, bytes, read);
+    }
+
+    status_t getCapturePosition(int64_t* frames, int64_t* time) final {
+        return stream->getCapturePosition(frames, time);
+    }
+
+    status_t standby() final { return stream->standby(); }
+
+    sp<DeviceHalInterface> hwDev() const { return audioHwDev->hwDevice(); }
+};
+
+}  // namespace android
diff --git a/services/audioflinger/datapath/VolumeInterface.h b/services/audioflinger/datapath/VolumeInterface.h
new file mode 100644
index 0000000..1564fe1
--- /dev/null
+++ b/services/audioflinger/datapath/VolumeInterface.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <system/audio.h>
+
+namespace android {
+
+class VolumeInterface : public virtual RefBase {
+public:
+    virtual void setMasterVolume(float value) = 0;
+    virtual void setMasterBalance(float balance) = 0;
+    virtual void setMasterMute(bool muted) = 0;
+    virtual void setStreamVolume(audio_stream_type_t stream, float value) = 0;
+    virtual void setStreamMute(audio_stream_type_t stream, bool muted) = 0;
+    // TODO(b/290699744) add "get" prefix for getter below.
+    virtual float streamVolume(audio_stream_type_t stream) const = 0;
+};
+
+}  // namespace android
diff --git a/services/audioflinger/timing/tests/mediasyncevent_tests.cpp b/services/audioflinger/timing/tests/mediasyncevent_tests.cpp
index 745bb35..ab2d88f 100644
--- a/services/audioflinger/timing/tests/mediasyncevent_tests.cpp
+++ b/services/audioflinger/timing/tests/mediasyncevent_tests.cpp
@@ -25,7 +25,8 @@
 using namespace android::audioflinger;
 
 namespace {
-
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wenum-constexpr-conversion"
 TEST(MediaSyncEventTests, Basic) {
     struct Cookie : public RefBase {};
 
@@ -66,5 +67,5 @@
     syncEvent->cancel();
     ASSERT_TRUE(syncEvent->isCancelled());
 }
-
+#pragma clang diagnostic pop
 } // namespace
diff --git a/services/audioflinger/timing/tests/synchronizedrecordstate_tests.cpp b/services/audioflinger/timing/tests/synchronizedrecordstate_tests.cpp
index 68f154d..82df059 100644
--- a/services/audioflinger/timing/tests/synchronizedrecordstate_tests.cpp
+++ b/services/audioflinger/timing/tests/synchronizedrecordstate_tests.cpp
@@ -26,6 +26,8 @@
 
 namespace {
 
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wenum-constexpr-conversion"
 TEST(SynchronizedRecordStateTests, Basic) {
     struct Cookie : public RefBase {};
 
@@ -74,5 +76,5 @@
     ASSERT_FALSE(triggered);
     ASSERT_TRUE(syncEvent->isCancelled());
 }
-
+#pragma clang diagnostic pop
 }
diff --git a/services/audiopolicy/engineconfigurable/parameter-framework/examples/Car/Android.bp b/services/audiopolicy/engineconfigurable/parameter-framework/examples/Car/Android.bp
index bc72484..7d2d293 100644
--- a/services/audiopolicy/engineconfigurable/parameter-framework/examples/Car/Android.bp
+++ b/services/audiopolicy/engineconfigurable/parameter-framework/examples/Car/Android.bp
@@ -55,6 +55,7 @@
 //
 prebuilt_etc {
     name: "parameter-framework.policy",
+    enabled: false, // TODO: This module depends on domaingeneratorpolicyrule_gen, which fails to build
     filename_from_src: true,
     vendor: true,
     src: ":domaingeneratorpolicyrule_gen",
@@ -68,6 +69,7 @@
 }
 genrule {
     name: "domaingeneratorpolicyrule_gen",
+    enabled: false, // TODO: This module fails to build
     defaults: ["domaingeneratorpolicyrule"],
     srcs: [
         ":audio_policy_pfw_toplevel",
diff --git a/services/audiopolicy/engineconfigurable/parameter-framework/examples/CarEmu/Android.bp b/services/audiopolicy/engineconfigurable/parameter-framework/examples/CarEmu/Android.bp
index 11da8c7..f825e5f 100644
--- a/services/audiopolicy/engineconfigurable/parameter-framework/examples/CarEmu/Android.bp
+++ b/services/audiopolicy/engineconfigurable/parameter-framework/examples/CarEmu/Android.bp
@@ -56,6 +56,7 @@
 //
 prebuilt_etc {
     name: "parameter-framework.policy",
+    enabled: false, // TODO: This module depends on domaingeneratorpolicyrule_gen, which fails to build
     filename_from_src: true,
     vendor: true,
     src: ":domaingeneratorpolicyrule_gen",
@@ -69,6 +70,7 @@
 }
 genrule {
     name: "domaingeneratorpolicyrule_gen",
+    enabled: false, // TODO: This module fails to build
     defaults: ["domaingeneratorpolicyrule"],
     srcs: [
         ":audio_policy_pfw_toplevel",
diff --git a/services/audiopolicy/engineconfigurable/parameter-framework/examples/Phone/Android.bp b/services/audiopolicy/engineconfigurable/parameter-framework/examples/Phone/Android.bp
index 91ffeb5..4a83cbc 100644
--- a/services/audiopolicy/engineconfigurable/parameter-framework/examples/Phone/Android.bp
+++ b/services/audiopolicy/engineconfigurable/parameter-framework/examples/Phone/Android.bp
@@ -55,6 +55,7 @@
 //
 prebuilt_etc {
     name: "parameter-framework.policy",
+    enabled: false, // TODO: This module depends on domaingeneratorpolicyrule_gen, which fails to build
     filename_from_src: true,
     vendor: true,
     src: ":domaingeneratorpolicyrule_gen",
@@ -68,6 +69,7 @@
 }
 genrule {
     name: "domaingeneratorpolicyrule_gen",
+    enabled: false, // TODO: This module fails to build
     defaults: ["domaingeneratorpolicyrule"],
     srcs: [
         ":audio_policy_pfw_toplevel",
diff --git a/services/audiopolicy/engineconfigurable/parameter-framework/examples/SettingsNoInput/Android.bp b/services/audiopolicy/engineconfigurable/parameter-framework/examples/SettingsNoInput/Android.bp
index cac63fc..89ab892 100644
--- a/services/audiopolicy/engineconfigurable/parameter-framework/examples/SettingsNoInput/Android.bp
+++ b/services/audiopolicy/engineconfigurable/parameter-framework/examples/SettingsNoInput/Android.bp
@@ -34,6 +34,7 @@
 
 prebuilt_etc {
     name: "parameter-framework.policy",
+    enabled: false, // TODO: This module depends on domaingeneratorpolicyrule_gen, which fails to build
     filename_from_src: true,
     vendor: true,
     src: ":domaingeneratorpolicyrule_gen",
@@ -47,6 +48,7 @@
 
 genrule {
     name: "domaingeneratorpolicyrule_gen",
+    enabled: false, // TODO: This module fails to build
     defaults: ["domaingeneratorpolicyrule"],
     srcs: [
         ":audio_policy_pfw_toplevel",
diff --git a/services/audiopolicy/engineconfigurable/parameter-framework/examples/SettingsNoOutput/Android.bp b/services/audiopolicy/engineconfigurable/parameter-framework/examples/SettingsNoOutput/Android.bp
index 337f358..4880547 100644
--- a/services/audiopolicy/engineconfigurable/parameter-framework/examples/SettingsNoOutput/Android.bp
+++ b/services/audiopolicy/engineconfigurable/parameter-framework/examples/SettingsNoOutput/Android.bp
@@ -34,6 +34,7 @@
 
 prebuilt_etc {
     name: "parameter-framework.policy",
+    enabled: false, // TODO: This module depends on domaingeneratorpolicyrule_gen, which fails to build
     filename_from_src: true,
     vendor: true,
     src: ":domaingeneratorpolicyrule_gen",
@@ -46,6 +47,7 @@
 }
 genrule {
     name: "domaingeneratorpolicyrule_gen",
+    enabled: false, // TODO: This module fails to build
     defaults: ["domaingeneratorpolicyrule"],
     srcs: [
         ":audio_policy_pfw_toplevel",
diff --git a/services/audiopolicy/tests/audiopolicymanager_tests.cpp b/services/audiopolicy/tests/audiopolicymanager_tests.cpp
index 15eae14..b56bb16 100644
--- a/services/audiopolicy/tests/audiopolicymanager_tests.cpp
+++ b/services/audiopolicy/tests/audiopolicymanager_tests.cpp
@@ -1905,7 +1905,7 @@
     audio_io_handle_t mOutput;
     audio_stream_type_t mStream = AUDIO_STREAM_DEFAULT;
     audio_port_handle_t mSelectedDeviceId = AUDIO_PORT_HANDLE_NONE;
-    audio_port_handle_t mPortId;
+    audio_port_handle_t mPortId = AUDIO_PORT_HANDLE_NONE;
     AudioPolicyInterface::output_type_t mOutputType;
     audio_attributes_t attr = AUDIO_ATTRIBUTES_INITIALIZER;
     bool mIsSpatialized;
diff --git a/services/camera/libcameraservice/CameraService.cpp b/services/camera/libcameraservice/CameraService.cpp
index 222f459..4757a42 100644
--- a/services/camera/libcameraservice/CameraService.cpp
+++ b/services/camera/libcameraservice/CameraService.cpp
@@ -2659,6 +2659,11 @@
         }
         case ICameraService::EVENT_USB_DEVICE_ATTACHED:
         case ICameraService::EVENT_USB_DEVICE_DETACHED: {
+            if (args.size() != 1) {
+                return Status::fromExceptionCode(Status::EX_ILLEGAL_ARGUMENT,
+                    "USB Device Event requires 1 argument");
+            }
+
             // Notify CameraProviderManager for lazy HALs
             mCameraProviderManager->notifyUsbDeviceEvent(eventId,
                                                         std::to_string(args[0]));
diff --git a/services/camera/libcameraservice/device3/Camera3OutputStream.cpp b/services/camera/libcameraservice/device3/Camera3OutputStream.cpp
index 7185895..f98636b 100644
--- a/services/camera/libcameraservice/device3/Camera3OutputStream.cpp
+++ b/services/camera/libcameraservice/device3/Camera3OutputStream.cpp
@@ -487,7 +487,7 @@
             bufferDeferred = true;
         } else {
             nsecs_t presentTime = mSyncToDisplay ?
-                    syncTimestampToDisplayLocked(captureTime, releaseFence->dup()) : captureTime;
+                    syncTimestampToDisplayLocked(captureTime, releaseFence) : captureTime;
 
             setTransform(transform, true/*mayChangeMirror*/);
             res = native_window_set_buffers_timestamp(mConsumer.get(), presentTime);
@@ -1412,7 +1412,7 @@
     }
 }
 
-nsecs_t Camera3OutputStream::syncTimestampToDisplayLocked(nsecs_t t, int releaseFence) {
+nsecs_t Camera3OutputStream::syncTimestampToDisplayLocked(nsecs_t t, sp<Fence> releaseFence) {
     nsecs_t currentTime = systemTime();
     if (!mFixedFps) {
         mLastCaptureTime = t;
@@ -1460,8 +1460,8 @@
                 mRefVsyncData = vsyncEventData;
                 mReferenceCaptureTime = t;
                 mReferenceArrivalTime = currentTime;
-                if (releaseFence != -1) {
-                    mReferenceFrameFence = new Fence(releaseFence);
+                if (releaseFence->isValid()) {
+                    mReferenceFrameFence = new Fence(releaseFence->dup());
                 } else {
                     mFenceSignalOffset = 0;
                 }
diff --git a/services/camera/libcameraservice/device3/Camera3OutputStream.h b/services/camera/libcameraservice/device3/Camera3OutputStream.h
index 0b456c0..65791a9 100644
--- a/services/camera/libcameraservice/device3/Camera3OutputStream.h
+++ b/services/camera/libcameraservice/device3/Camera3OutputStream.h
@@ -446,7 +446,7 @@
     static constexpr nsecs_t kTimelineThresholdNs = 1000000LL; // 1 millisecond
     static constexpr float kMaxIntervalRatioDeviation = 0.05f;
     static constexpr int kMaxTimelines = 2;
-    nsecs_t syncTimestampToDisplayLocked(nsecs_t t, int releaseFence);
+    nsecs_t syncTimestampToDisplayLocked(nsecs_t t, sp<Fence> releaseFence);
 
     // In case of fence being used
     sp<Fence> mReferenceFrameFence;
diff --git a/services/mediametrics/AudioAnalytics.cpp b/services/mediametrics/AudioAnalytics.cpp
index 59d1ae4..bd4ac38 100644
--- a/services/mediametrics/AudioAnalytics.cpp
+++ b/services/mediametrics/AudioAnalytics.cpp
@@ -242,6 +242,7 @@
     "channel_count_hardware",
     "sample_rate_hardware",
     "uid",
+    "sample_rate_client",
 };
 
 static constexpr const char * HeadTrackerDeviceEnabledFields[] {
@@ -1379,6 +1380,10 @@
 
     const auto uid = item->getUid();
 
+    int32_t sampleRateClient = 0;
+    mAudioAnalytics.mAnalyticsState->timeMachine().get(
+            key, AMEDIAMETRICS_PROP_SAMPLERATECLIENT, &sampleRateClient);
+
     LOG(LOG_LEVEL) << "key:" << key
             << " path:" << path
             << " direction:" << direction << "(" << directionStr << ")"
@@ -1402,7 +1407,8 @@
             << " format_hardware:" << formatHardware << "(" << formatHardwareStr << ")"
             << " channel_count_hardware:" << channelCountHardware
             << " sample_rate_hardware: " << sampleRateHardware
-            << " uid: " << uid;
+            << " uid: " << uid
+            << " sample_rate_client: " << sampleRateClient;
 
     if (mAudioAnalytics.mDeliverStatistics) {
         const stats::media_metrics::BytesField bf_serialized(
@@ -1431,6 +1437,7 @@
                 , channelCountHardware
                 , sampleRateHardware
                 , uid
+                , sampleRateClient
                 );
         std::stringstream ss;
         ss << "result:" << result;
@@ -1458,6 +1465,7 @@
                 , channelCountHardware
                 , sampleRateHardware
                 , uid
+                , sampleRateClient
                 );
         ss << " " << fieldsStr;
         std::string str = ss.str();