diff --git a/media/libaudiohal/4.0/ConversionHelperHidl.cpp b/media/libaudiohal/4.0/ConversionHelperHidl.cpp
new file mode 100644
index 0000000..f60bf8b
--- /dev/null
+++ b/media/libaudiohal/4.0/ConversionHelperHidl.cpp
@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#include <string.h>
+
+#define LOG_TAG "HalHidl"
+#include <media/AudioParameter.h>
+#include <utils/Log.h>
+
+#include "ConversionHelperHidl.h"
+
+using ::android::hardware::audio::V2_0::Result;
+
+namespace android {
+
+// static
+status_t ConversionHelperHidl::keysFromHal(const String8& keys, hidl_vec<hidl_string> *hidlKeys) {
+    AudioParameter halKeys(keys);
+    if (halKeys.size() == 0) return BAD_VALUE;
+    hidlKeys->resize(halKeys.size());
+    //FIXME:  keyStreamSupportedChannels and keyStreamSupportedSamplingRates come with a
+    // "keyFormat=<value>" pair. We need to transform it into a single key string so that it is
+    // carried over to the legacy HAL via HIDL.
+    String8 value;
+    bool keepFormatValue = halKeys.size() == 2 &&
+         (halKeys.get(String8(AudioParameter::keyStreamSupportedChannels), value) == NO_ERROR ||
+         halKeys.get(String8(AudioParameter::keyStreamSupportedSamplingRates), value) == NO_ERROR);
+
+    for (size_t i = 0; i < halKeys.size(); ++i) {
+        String8 key;
+        status_t status = halKeys.getAt(i, key);
+        if (status != OK) return status;
+        if (keepFormatValue && key == AudioParameter::keyFormat) {
+            AudioParameter formatParam;
+            halKeys.getAt(i, key, value);
+            formatParam.add(key, value);
+            key = formatParam.toString();
+        }
+        (*hidlKeys)[i] = key.string();
+    }
+    return OK;
+}
+
+// static
+status_t ConversionHelperHidl::parametersFromHal(
+        const String8& kvPairs, hidl_vec<ParameterValue> *hidlParams) {
+    AudioParameter params(kvPairs);
+    if (params.size() == 0) return BAD_VALUE;
+    hidlParams->resize(params.size());
+    for (size_t i = 0; i < params.size(); ++i) {
+        String8 key, value;
+        status_t status = params.getAt(i, key, value);
+        if (status != OK) return status;
+        (*hidlParams)[i].key = key.string();
+        (*hidlParams)[i].value = value.string();
+    }
+    return OK;
+}
+
+// static
+void ConversionHelperHidl::parametersToHal(
+        const hidl_vec<ParameterValue>& parameters, String8 *values) {
+    AudioParameter params;
+    for (size_t i = 0; i < parameters.size(); ++i) {
+        params.add(String8(parameters[i].key.c_str()), String8(parameters[i].value.c_str()));
+    }
+    values->setTo(params.toString());
+}
+
+ConversionHelperHidl::ConversionHelperHidl(const char* className)
+        : mClassName(className) {
+}
+
+// static
+status_t ConversionHelperHidl::analyzeResult(const Result& result) {
+    switch (result) {
+        case Result::OK: return OK;
+        case Result::INVALID_ARGUMENTS: return BAD_VALUE;
+        case Result::INVALID_STATE: return NOT_ENOUGH_DATA;
+        case Result::NOT_INITIALIZED: return NO_INIT;
+        case Result::NOT_SUPPORTED: return INVALID_OPERATION;
+        default: return NO_INIT;
+    }
+}
+
+void ConversionHelperHidl::emitError(const char* funcName, const char* description) {
+    ALOGE("%s %p %s: %s (from rpc)", mClassName, this, funcName, description);
+}
+
+}  // namespace android
diff --git a/media/libaudiohal/4.0/ConversionHelperHidl.h b/media/libaudiohal/4.0/ConversionHelperHidl.h
new file mode 100644
index 0000000..c356f37
--- /dev/null
+++ b/media/libaudiohal/4.0/ConversionHelperHidl.h
@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#ifndef ANDROID_HARDWARE_CONVERSION_HELPER_HIDL_H
+#define ANDROID_HARDWARE_CONVERSION_HELPER_HIDL_H
+
+#include <android/hardware/audio/2.0/types.h>
+#include <hidl/HidlSupport.h>
+#include <utils/String8.h>
+
+using ::android::hardware::audio::V2_0::ParameterValue;
+using ::android::hardware::Return;
+using ::android::hardware::hidl_string;
+using ::android::hardware::hidl_vec;
+
+namespace android {
+
+class ConversionHelperHidl {
+  protected:
+    static status_t keysFromHal(const String8& keys, hidl_vec<hidl_string> *hidlKeys);
+    static status_t parametersFromHal(const String8& kvPairs, hidl_vec<ParameterValue> *hidlParams);
+    static void parametersToHal(const hidl_vec<ParameterValue>& parameters, String8 *values);
+
+    ConversionHelperHidl(const char* className);
+
+    template<typename R, typename T>
+    status_t processReturn(const char* funcName, const Return<R>& ret, T *retval) {
+        if (ret.isOk()) {
+            // This way it also works for enum class to unscoped enum conversion.
+            *retval = static_cast<T>(static_cast<R>(ret));
+            return OK;
+        }
+        return processReturn(funcName, ret);
+    }
+
+    template<typename T>
+    status_t processReturn(const char* funcName, const Return<T>& ret) {
+        if (!ret.isOk()) {
+            emitError(funcName, ret.description().c_str());
+        }
+        return ret.isOk() ? OK : FAILED_TRANSACTION;
+    }
+
+    status_t processReturn(const char* funcName, const Return<hardware::audio::V2_0::Result>& ret) {
+        if (!ret.isOk()) {
+            emitError(funcName, ret.description().c_str());
+        }
+        return ret.isOk() ? analyzeResult(ret) : FAILED_TRANSACTION;
+    }
+
+    template<typename T>
+    status_t processReturn(
+            const char* funcName, const Return<T>& ret, hardware::audio::V2_0::Result retval) {
+        if (!ret.isOk()) {
+            emitError(funcName, ret.description().c_str());
+        }
+        return ret.isOk() ? analyzeResult(retval) : FAILED_TRANSACTION;
+    }
+
+  private:
+    const char* mClassName;
+
+    static status_t analyzeResult(const hardware::audio::V2_0::Result& result);
+
+    void emitError(const char* funcName, const char* description);
+};
+
+}  // namespace android
+
+#endif // ANDROID_HARDWARE_CONVERSION_HELPER_HIDL_H
diff --git a/media/libaudiohal/4.0/DeviceHalHidl.cpp b/media/libaudiohal/4.0/DeviceHalHidl.cpp
new file mode 100644
index 0000000..0d9c6c4
--- /dev/null
+++ b/media/libaudiohal/4.0/DeviceHalHidl.cpp
@@ -0,0 +1,358 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#include <stdio.h>
+
+#define LOG_TAG "DeviceHalHidl"
+//#define LOG_NDEBUG 0
+
+#include <android/hardware/audio/2.0/IPrimaryDevice.h>
+#include <cutils/native_handle.h>
+#include <hwbinder/IPCThreadState.h>
+#include <utils/Log.h>
+
+#include "DeviceHalHidl.h"
+#include "HidlUtils.h"
+#include "StreamHalHidl.h"
+
+using ::android::hardware::audio::common::V2_0::AudioConfig;
+using ::android::hardware::audio::common::V2_0::AudioDevice;
+using ::android::hardware::audio::common::V2_0::AudioInputFlag;
+using ::android::hardware::audio::common::V2_0::AudioOutputFlag;
+using ::android::hardware::audio::common::V2_0::AudioPatchHandle;
+using ::android::hardware::audio::common::V2_0::AudioPort;
+using ::android::hardware::audio::common::V2_0::AudioPortConfig;
+using ::android::hardware::audio::common::V2_0::AudioMode;
+using ::android::hardware::audio::common::V2_0::AudioSource;
+using ::android::hardware::audio::common::V2_0::HidlUtils;
+using ::android::hardware::audio::V2_0::DeviceAddress;
+using ::android::hardware::audio::V2_0::IPrimaryDevice;
+using ::android::hardware::audio::V2_0::ParameterValue;
+using ::android::hardware::audio::V2_0::Result;
+using ::android::hardware::hidl_string;
+using ::android::hardware::hidl_vec;
+
+namespace android {
+
+namespace {
+
+status_t deviceAddressFromHal(
+        audio_devices_t device, const char* halAddress, DeviceAddress* address) {
+    address->device = AudioDevice(device);
+
+    if (address == nullptr || strnlen(halAddress, AUDIO_DEVICE_MAX_ADDRESS_LEN) == 0) {
+        return OK;
+    }
+    const bool isInput = (device & AUDIO_DEVICE_BIT_IN) != 0;
+    if (isInput) device &= ~AUDIO_DEVICE_BIT_IN;
+    if ((!isInput && (device & AUDIO_DEVICE_OUT_ALL_A2DP) != 0)
+            || (isInput && (device & AUDIO_DEVICE_IN_BLUETOOTH_A2DP) != 0)) {
+        int status = sscanf(halAddress,
+                "%hhX:%hhX:%hhX:%hhX:%hhX:%hhX",
+                &address->address.mac[0], &address->address.mac[1], &address->address.mac[2],
+                &address->address.mac[3], &address->address.mac[4], &address->address.mac[5]);
+        return status == 6 ? OK : BAD_VALUE;
+    } else if ((!isInput && (device & AUDIO_DEVICE_OUT_IP) != 0)
+            || (isInput && (device & AUDIO_DEVICE_IN_IP) != 0)) {
+        int status = sscanf(halAddress,
+                "%hhu.%hhu.%hhu.%hhu",
+                &address->address.ipv4[0], &address->address.ipv4[1],
+                &address->address.ipv4[2], &address->address.ipv4[3]);
+        return status == 4 ? OK : BAD_VALUE;
+    } else if ((!isInput && (device & AUDIO_DEVICE_OUT_ALL_USB)) != 0
+            || (isInput && (device & AUDIO_DEVICE_IN_ALL_USB)) != 0) {
+        int status = sscanf(halAddress,
+                "card=%d;device=%d",
+                &address->address.alsa.card, &address->address.alsa.device);
+        return status == 2 ? OK : BAD_VALUE;
+    } else if ((!isInput && (device & AUDIO_DEVICE_OUT_BUS) != 0)
+            || (isInput && (device & AUDIO_DEVICE_IN_BUS) != 0)) {
+        if (halAddress != NULL) {
+            address->busAddress = halAddress;
+            return OK;
+        }
+        return BAD_VALUE;
+    } else if ((!isInput && (device & AUDIO_DEVICE_OUT_REMOTE_SUBMIX)) != 0
+            || (isInput && (device & AUDIO_DEVICE_IN_REMOTE_SUBMIX) != 0)) {
+        if (halAddress != NULL) {
+            address->rSubmixAddress = halAddress;
+            return OK;
+        }
+        return BAD_VALUE;
+    }
+    return OK;
+}
+
+}  // namespace
+
+DeviceHalHidl::DeviceHalHidl(const sp<IDevice>& device)
+        : ConversionHelperHidl("Device"), mDevice(device),
+          mPrimaryDevice(IPrimaryDevice::castFrom(device)) {
+}
+
+DeviceHalHidl::~DeviceHalHidl() {
+    if (mDevice != 0) {
+        mDevice.clear();
+        hardware::IPCThreadState::self()->flushCommands();
+    }
+}
+
+status_t DeviceHalHidl::getSupportedDevices(uint32_t*) {
+    // Obsolete.
+    return INVALID_OPERATION;
+}
+
+status_t DeviceHalHidl::initCheck() {
+    if (mDevice == 0) return NO_INIT;
+    return processReturn("initCheck", mDevice->initCheck());
+}
+
+status_t DeviceHalHidl::setVoiceVolume(float volume) {
+    if (mDevice == 0) return NO_INIT;
+    if (mPrimaryDevice == 0) return INVALID_OPERATION;
+    return processReturn("setVoiceVolume", mPrimaryDevice->setVoiceVolume(volume));
+}
+
+status_t DeviceHalHidl::setMasterVolume(float volume) {
+    if (mDevice == 0) return NO_INIT;
+    if (mPrimaryDevice == 0) return INVALID_OPERATION;
+    return processReturn("setMasterVolume", mPrimaryDevice->setMasterVolume(volume));
+}
+
+status_t DeviceHalHidl::getMasterVolume(float *volume) {
+    if (mDevice == 0) return NO_INIT;
+    if (mPrimaryDevice == 0) return INVALID_OPERATION;
+    Result retval;
+    Return<void> ret = mPrimaryDevice->getMasterVolume(
+            [&](Result r, float v) {
+                retval = r;
+                if (retval == Result::OK) {
+                    *volume = v;
+                }
+            });
+    return processReturn("getMasterVolume", ret, retval);
+}
+
+status_t DeviceHalHidl::setMode(audio_mode_t mode) {
+    if (mDevice == 0) return NO_INIT;
+    if (mPrimaryDevice == 0) return INVALID_OPERATION;
+    return processReturn("setMode", mPrimaryDevice->setMode(AudioMode(mode)));
+}
+
+status_t DeviceHalHidl::setMicMute(bool state) {
+    if (mDevice == 0) return NO_INIT;
+    return processReturn("setMicMute", mDevice->setMicMute(state));
+}
+
+status_t DeviceHalHidl::getMicMute(bool *state) {
+    if (mDevice == 0) return NO_INIT;
+    Result retval;
+    Return<void> ret = mDevice->getMicMute(
+            [&](Result r, bool mute) {
+                retval = r;
+                if (retval == Result::OK) {
+                    *state = mute;
+                }
+            });
+    return processReturn("getMicMute", ret, retval);
+}
+
+status_t DeviceHalHidl::setMasterMute(bool state) {
+    if (mDevice == 0) return NO_INIT;
+    return processReturn("setMasterMute", mDevice->setMasterMute(state));
+}
+
+status_t DeviceHalHidl::getMasterMute(bool *state) {
+    if (mDevice == 0) return NO_INIT;
+    Result retval;
+    Return<void> ret = mDevice->getMasterMute(
+            [&](Result r, bool mute) {
+                retval = r;
+                if (retval == Result::OK) {
+                    *state = mute;
+                }
+            });
+    return processReturn("getMasterMute", ret, retval);
+}
+
+status_t DeviceHalHidl::setParameters(const String8& kvPairs) {
+    if (mDevice == 0) return NO_INIT;
+    hidl_vec<ParameterValue> hidlParams;
+    status_t status = parametersFromHal(kvPairs, &hidlParams);
+    if (status != OK) return status;
+    return processReturn("setParameters", mDevice->setParameters(hidlParams));
+}
+
+status_t DeviceHalHidl::getParameters(const String8& keys, String8 *values) {
+    values->clear();
+    if (mDevice == 0) return NO_INIT;
+    hidl_vec<hidl_string> hidlKeys;
+    status_t status = keysFromHal(keys, &hidlKeys);
+    if (status != OK) return status;
+    Result retval;
+    Return<void> ret = mDevice->getParameters(
+            hidlKeys,
+            [&](Result r, const hidl_vec<ParameterValue>& parameters) {
+                retval = r;
+                if (retval == Result::OK) {
+                    parametersToHal(parameters, values);
+                }
+            });
+    return processReturn("getParameters", ret, retval);
+}
+
+status_t DeviceHalHidl::getInputBufferSize(
+        const struct audio_config *config, size_t *size) {
+    if (mDevice == 0) return NO_INIT;
+    AudioConfig hidlConfig;
+    HidlUtils::audioConfigFromHal(*config, &hidlConfig);
+    Result retval;
+    Return<void> ret = mDevice->getInputBufferSize(
+            hidlConfig,
+            [&](Result r, uint64_t bufferSize) {
+                retval = r;
+                if (retval == Result::OK) {
+                    *size = static_cast<size_t>(bufferSize);
+                }
+            });
+    return processReturn("getInputBufferSize", ret, retval);
+}
+
+status_t DeviceHalHidl::openOutputStream(
+        audio_io_handle_t handle,
+        audio_devices_t devices,
+        audio_output_flags_t flags,
+        struct audio_config *config,
+        const char *address,
+        sp<StreamOutHalInterface> *outStream) {
+    if (mDevice == 0) return NO_INIT;
+    DeviceAddress hidlDevice;
+    status_t status = deviceAddressFromHal(devices, address, &hidlDevice);
+    if (status != OK) return status;
+    AudioConfig hidlConfig;
+    HidlUtils::audioConfigFromHal(*config, &hidlConfig);
+    Result retval = Result::NOT_INITIALIZED;
+    Return<void> ret = mDevice->openOutputStream(
+            handle,
+            hidlDevice,
+            hidlConfig,
+            AudioOutputFlag(flags),
+            [&](Result r, const sp<IStreamOut>& result, const AudioConfig& suggestedConfig) {
+                retval = r;
+                if (retval == Result::OK) {
+                    *outStream = new StreamOutHalHidl(result);
+                }
+                HidlUtils::audioConfigToHal(suggestedConfig, config);
+            });
+    return processReturn("openOutputStream", ret, retval);
+}
+
+status_t DeviceHalHidl::openInputStream(
+        audio_io_handle_t handle,
+        audio_devices_t devices,
+        struct audio_config *config,
+        audio_input_flags_t flags,
+        const char *address,
+        audio_source_t source,
+        sp<StreamInHalInterface> *inStream) {
+    if (mDevice == 0) return NO_INIT;
+    DeviceAddress hidlDevice;
+    status_t status = deviceAddressFromHal(devices, address, &hidlDevice);
+    if (status != OK) return status;
+    AudioConfig hidlConfig;
+    HidlUtils::audioConfigFromHal(*config, &hidlConfig);
+    Result retval = Result::NOT_INITIALIZED;
+    Return<void> ret = mDevice->openInputStream(
+            handle,
+            hidlDevice,
+            hidlConfig,
+            AudioInputFlag(flags),
+            AudioSource(source),
+            [&](Result r, const sp<IStreamIn>& result, const AudioConfig& suggestedConfig) {
+                retval = r;
+                if (retval == Result::OK) {
+                    *inStream = new StreamInHalHidl(result);
+                }
+                HidlUtils::audioConfigToHal(suggestedConfig, config);
+            });
+    return processReturn("openInputStream", ret, retval);
+}
+
+status_t DeviceHalHidl::supportsAudioPatches(bool *supportsPatches) {
+    if (mDevice == 0) return NO_INIT;
+    return processReturn("supportsAudioPatches", mDevice->supportsAudioPatches(), supportsPatches);
+}
+
+status_t DeviceHalHidl::createAudioPatch(
+        unsigned int num_sources,
+        const struct audio_port_config *sources,
+        unsigned int num_sinks,
+        const struct audio_port_config *sinks,
+        audio_patch_handle_t *patch) {
+    if (mDevice == 0) return NO_INIT;
+    hidl_vec<AudioPortConfig> hidlSources, hidlSinks;
+    HidlUtils::audioPortConfigsFromHal(num_sources, sources, &hidlSources);
+    HidlUtils::audioPortConfigsFromHal(num_sinks, sinks, &hidlSinks);
+    Result retval;
+    Return<void> ret = mDevice->createAudioPatch(
+            hidlSources, hidlSinks,
+            [&](Result r, AudioPatchHandle hidlPatch) {
+                retval = r;
+                if (retval == Result::OK) {
+                    *patch = static_cast<audio_patch_handle_t>(hidlPatch);
+                }
+            });
+    return processReturn("createAudioPatch", ret, retval);
+}
+
+status_t DeviceHalHidl::releaseAudioPatch(audio_patch_handle_t patch) {
+    if (mDevice == 0) return NO_INIT;
+    return processReturn("releaseAudioPatch", mDevice->releaseAudioPatch(patch));
+}
+
+status_t DeviceHalHidl::getAudioPort(struct audio_port *port) {
+    if (mDevice == 0) return NO_INIT;
+    AudioPort hidlPort;
+    HidlUtils::audioPortFromHal(*port, &hidlPort);
+    Result retval;
+    Return<void> ret = mDevice->getAudioPort(
+            hidlPort,
+            [&](Result r, const AudioPort& p) {
+                retval = r;
+                if (retval == Result::OK) {
+                    HidlUtils::audioPortToHal(p, port);
+                }
+            });
+    return processReturn("getAudioPort", ret, retval);
+}
+
+status_t DeviceHalHidl::setAudioPortConfig(const struct audio_port_config *config) {
+    if (mDevice == 0) return NO_INIT;
+    AudioPortConfig hidlConfig;
+    HidlUtils::audioPortConfigFromHal(*config, &hidlConfig);
+    return processReturn("setAudioPortConfig", mDevice->setAudioPortConfig(hidlConfig));
+}
+
+status_t DeviceHalHidl::dump(int fd) {
+    if (mDevice == 0) return NO_INIT;
+    native_handle_t* hidlHandle = native_handle_create(1, 0);
+    hidlHandle->data[0] = fd;
+    Return<void> ret = mDevice->debugDump(hidlHandle);
+    native_handle_delete(hidlHandle);
+    return processReturn("dump", ret);
+}
+
+} // namespace android
diff --git a/media/libaudiohal/4.0/DeviceHalHidl.h b/media/libaudiohal/4.0/DeviceHalHidl.h
new file mode 100644
index 0000000..8651b51
--- /dev/null
+++ b/media/libaudiohal/4.0/DeviceHalHidl.h
@@ -0,0 +1,126 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#ifndef ANDROID_HARDWARE_DEVICE_HAL_HIDL_H
+#define ANDROID_HARDWARE_DEVICE_HAL_HIDL_H
+
+#include <android/hardware/audio/2.0/IDevice.h>
+#include <android/hardware/audio/2.0/IPrimaryDevice.h>
+#include <media/audiohal/DeviceHalInterface.h>
+
+#include "ConversionHelperHidl.h"
+
+using ::android::hardware::audio::V2_0::IDevice;
+using ::android::hardware::audio::V2_0::IPrimaryDevice;
+using ::android::hardware::Return;
+
+namespace android {
+
+class DeviceHalHidl : public DeviceHalInterface, public ConversionHelperHidl
+{
+  public:
+    // Sets the value of 'devices' to a bitmask of 1 or more values of audio_devices_t.
+    virtual status_t getSupportedDevices(uint32_t *devices);
+
+    // Check to see if the audio hardware interface has been initialized.
+    virtual status_t initCheck();
+
+    // Set the audio volume of a voice call. Range is between 0.0 and 1.0.
+    virtual status_t setVoiceVolume(float volume);
+
+    // Set the audio volume for all audio activities other than voice call.
+    virtual status_t setMasterVolume(float volume);
+
+    // Get the current master volume value for the HAL.
+    virtual status_t getMasterVolume(float *volume);
+
+    // Called when the audio mode changes.
+    virtual status_t setMode(audio_mode_t mode);
+
+    // Muting control.
+    virtual status_t setMicMute(bool state);
+    virtual status_t getMicMute(bool *state);
+    virtual status_t setMasterMute(bool state);
+    virtual status_t getMasterMute(bool *state);
+
+    // Set global audio parameters.
+    virtual status_t setParameters(const String8& kvPairs);
+
+    // Get global audio parameters.
+    virtual status_t getParameters(const String8& keys, String8 *values);
+
+    // Returns audio input buffer size according to parameters passed.
+    virtual status_t getInputBufferSize(const struct audio_config *config,
+            size_t *size);
+
+    // Creates and opens the audio hardware output stream. The stream is closed
+    // by releasing all references to the returned object.
+    virtual status_t openOutputStream(
+            audio_io_handle_t handle,
+            audio_devices_t devices,
+            audio_output_flags_t flags,
+            struct audio_config *config,
+            const char *address,
+            sp<StreamOutHalInterface> *outStream);
+
+    // Creates and opens the audio hardware input stream. The stream is closed
+    // by releasing all references to the returned object.
+    virtual status_t openInputStream(
+            audio_io_handle_t handle,
+            audio_devices_t devices,
+            struct audio_config *config,
+            audio_input_flags_t flags,
+            const char *address,
+            audio_source_t source,
+            sp<StreamInHalInterface> *inStream);
+
+    // Returns whether createAudioPatch and releaseAudioPatch operations are supported.
+    virtual status_t supportsAudioPatches(bool *supportsPatches);
+
+    // Creates an audio patch between several source and sink ports.
+    virtual status_t createAudioPatch(
+            unsigned int num_sources,
+            const struct audio_port_config *sources,
+            unsigned int num_sinks,
+            const struct audio_port_config *sinks,
+            audio_patch_handle_t *patch);
+
+    // Releases an audio patch.
+    virtual status_t releaseAudioPatch(audio_patch_handle_t patch);
+
+    // Fills the list of supported attributes for a given audio port.
+    virtual status_t getAudioPort(struct audio_port *port);
+
+    // Set audio port configuration.
+    virtual status_t setAudioPortConfig(const struct audio_port_config *config);
+
+    virtual status_t dump(int fd);
+
+  private:
+    friend class DevicesFactoryHalHidl;
+    sp<IDevice> mDevice;
+    sp<IPrimaryDevice> mPrimaryDevice;  // Null if it's not a primary device.
+
+    // Can not be constructed directly by clients.
+    explicit DeviceHalHidl(const sp<IDevice>& device);
+
+    // The destructor automatically closes the device.
+    virtual ~DeviceHalHidl();
+};
+
+} // namespace android
+
+#endif // ANDROID_HARDWARE_DEVICE_HAL_HIDL_H
diff --git a/media/libaudiohal/4.0/DeviceHalLocal.cpp b/media/libaudiohal/4.0/DeviceHalLocal.cpp
new file mode 100644
index 0000000..fc098f5
--- /dev/null
+++ b/media/libaudiohal/4.0/DeviceHalLocal.cpp
@@ -0,0 +1,199 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#define LOG_TAG "DeviceHalLocal"
+//#define LOG_NDEBUG 0
+
+#include <utils/Log.h>
+
+#include "DeviceHalLocal.h"
+#include "StreamHalLocal.h"
+
+namespace android {
+
+DeviceHalLocal::DeviceHalLocal(audio_hw_device_t *dev)
+        : mDev(dev) {
+}
+
+DeviceHalLocal::~DeviceHalLocal() {
+    int status = audio_hw_device_close(mDev);
+    ALOGW_IF(status, "Error closing audio hw device %p: %s", mDev, strerror(-status));
+    mDev = 0;
+}
+
+status_t DeviceHalLocal::getSupportedDevices(uint32_t *devices) {
+    if (mDev->get_supported_devices == NULL) return INVALID_OPERATION;
+    *devices = mDev->get_supported_devices(mDev);
+    return OK;
+}
+
+status_t DeviceHalLocal::initCheck() {
+    return mDev->init_check(mDev);
+}
+
+status_t DeviceHalLocal::setVoiceVolume(float volume) {
+    return mDev->set_voice_volume(mDev, volume);
+}
+
+status_t DeviceHalLocal::setMasterVolume(float volume) {
+    if (mDev->set_master_volume == NULL) return INVALID_OPERATION;
+    return mDev->set_master_volume(mDev, volume);
+}
+
+status_t DeviceHalLocal::getMasterVolume(float *volume) {
+    if (mDev->get_master_volume == NULL) return INVALID_OPERATION;
+    return mDev->get_master_volume(mDev, volume);
+}
+
+status_t DeviceHalLocal::setMode(audio_mode_t mode) {
+    return mDev->set_mode(mDev, mode);
+}
+
+status_t DeviceHalLocal::setMicMute(bool state) {
+    return mDev->set_mic_mute(mDev, state);
+}
+
+status_t DeviceHalLocal::getMicMute(bool *state) {
+    return mDev->get_mic_mute(mDev, state);
+}
+
+status_t DeviceHalLocal::setMasterMute(bool state) {
+    if (mDev->set_master_mute == NULL) return INVALID_OPERATION;
+    return mDev->set_master_mute(mDev, state);
+}
+
+status_t DeviceHalLocal::getMasterMute(bool *state) {
+    if (mDev->get_master_mute == NULL) return INVALID_OPERATION;
+    return mDev->get_master_mute(mDev, state);
+}
+
+status_t DeviceHalLocal::setParameters(const String8& kvPairs) {
+    return mDev->set_parameters(mDev, kvPairs.string());
+}
+
+status_t DeviceHalLocal::getParameters(const String8& keys, String8 *values) {
+    char *halValues = mDev->get_parameters(mDev, keys.string());
+    if (halValues != NULL) {
+        values->setTo(halValues);
+        free(halValues);
+    } else {
+        values->clear();
+    }
+    return OK;
+}
+
+status_t DeviceHalLocal::getInputBufferSize(
+        const struct audio_config *config, size_t *size) {
+    *size = mDev->get_input_buffer_size(mDev, config);
+    return OK;
+}
+
+status_t DeviceHalLocal::openOutputStream(
+        audio_io_handle_t handle,
+        audio_devices_t devices,
+        audio_output_flags_t flags,
+        struct audio_config *config,
+        const char *address,
+        sp<StreamOutHalInterface> *outStream) {
+    audio_stream_out_t *halStream;
+    ALOGV("open_output_stream handle: %d devices: %x flags: %#x"
+            "srate: %d format %#x channels %x address %s",
+            handle, devices, flags,
+            config->sample_rate, config->format, config->channel_mask,
+            address);
+    int openResut = mDev->open_output_stream(
+            mDev, handle, devices, flags, config, &halStream, address);
+    if (openResut == OK) {
+        *outStream = new StreamOutHalLocal(halStream, this);
+    }
+    ALOGV("open_output_stream status %d stream %p", openResut, halStream);
+    return openResut;
+}
+
+status_t DeviceHalLocal::openInputStream(
+        audio_io_handle_t handle,
+        audio_devices_t devices,
+        struct audio_config *config,
+        audio_input_flags_t flags,
+        const char *address,
+        audio_source_t source,
+        sp<StreamInHalInterface> *inStream) {
+    audio_stream_in_t *halStream;
+    ALOGV("open_input_stream handle: %d devices: %x flags: %#x "
+            "srate: %d format %#x channels %x address %s source %d",
+            handle, devices, flags,
+            config->sample_rate, config->format, config->channel_mask,
+            address, source);
+    int openResult = mDev->open_input_stream(
+            mDev, handle, devices, config, &halStream, flags, address, source);
+    if (openResult == OK) {
+        *inStream = new StreamInHalLocal(halStream, this);
+    }
+    ALOGV("open_input_stream status %d stream %p", openResult, inStream);
+    return openResult;
+}
+
+status_t DeviceHalLocal::supportsAudioPatches(bool *supportsPatches) {
+    *supportsPatches = version() >= AUDIO_DEVICE_API_VERSION_3_0;
+    return OK;
+}
+
+status_t DeviceHalLocal::createAudioPatch(
+        unsigned int num_sources,
+        const struct audio_port_config *sources,
+        unsigned int num_sinks,
+        const struct audio_port_config *sinks,
+        audio_patch_handle_t *patch) {
+    if (version() >= AUDIO_DEVICE_API_VERSION_3_0) {
+        return mDev->create_audio_patch(
+                mDev, num_sources, sources, num_sinks, sinks, patch);
+    } else {
+        return INVALID_OPERATION;
+    }
+}
+
+status_t DeviceHalLocal::releaseAudioPatch(audio_patch_handle_t patch) {
+    if (version() >= AUDIO_DEVICE_API_VERSION_3_0) {
+        return mDev->release_audio_patch(mDev, patch);
+    } else {
+        return INVALID_OPERATION;
+    }
+}
+
+status_t DeviceHalLocal::getAudioPort(struct audio_port *port) {
+    return mDev->get_audio_port(mDev, port);
+}
+
+status_t DeviceHalLocal::setAudioPortConfig(const struct audio_port_config *config) {
+    if (version() >= AUDIO_DEVICE_API_VERSION_3_0)
+        return mDev->set_audio_port_config(mDev, config);
+    else
+        return INVALID_OPERATION;
+}
+
+status_t DeviceHalLocal::dump(int fd) {
+    return mDev->dump(mDev, fd);
+}
+
+void DeviceHalLocal::closeOutputStream(struct audio_stream_out *stream_out) {
+    mDev->close_output_stream(mDev, stream_out);
+}
+
+void DeviceHalLocal::closeInputStream(struct audio_stream_in *stream_in) {
+    mDev->close_input_stream(mDev, stream_in);
+}
+
+} // namespace android
diff --git a/media/libaudiohal/4.0/DeviceHalLocal.h b/media/libaudiohal/4.0/DeviceHalLocal.h
new file mode 100644
index 0000000..865f296
--- /dev/null
+++ b/media/libaudiohal/4.0/DeviceHalLocal.h
@@ -0,0 +1,124 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#ifndef ANDROID_HARDWARE_DEVICE_HAL_LOCAL_H
+#define ANDROID_HARDWARE_DEVICE_HAL_LOCAL_H
+
+#include <hardware/audio.h>
+#include <media/audiohal/DeviceHalInterface.h>
+
+namespace android {
+
+class DeviceHalLocal : public DeviceHalInterface
+{
+  public:
+    // Sets the value of 'devices' to a bitmask of 1 or more values of audio_devices_t.
+    virtual status_t getSupportedDevices(uint32_t *devices);
+
+    // Check to see if the audio hardware interface has been initialized.
+    virtual status_t initCheck();
+
+    // Set the audio volume of a voice call. Range is between 0.0 and 1.0.
+    virtual status_t setVoiceVolume(float volume);
+
+    // Set the audio volume for all audio activities other than voice call.
+    virtual status_t setMasterVolume(float volume);
+
+    // Get the current master volume value for the HAL.
+    virtual status_t getMasterVolume(float *volume);
+
+    // Called when the audio mode changes.
+    virtual status_t setMode(audio_mode_t mode);
+
+    // Muting control.
+    virtual status_t setMicMute(bool state);
+    virtual status_t getMicMute(bool *state);
+    virtual status_t setMasterMute(bool state);
+    virtual status_t getMasterMute(bool *state);
+
+    // Set global audio parameters.
+    virtual status_t setParameters(const String8& kvPairs);
+
+    // Get global audio parameters.
+    virtual status_t getParameters(const String8& keys, String8 *values);
+
+    // Returns audio input buffer size according to parameters passed.
+    virtual status_t getInputBufferSize(const struct audio_config *config,
+            size_t *size);
+
+    // Creates and opens the audio hardware output stream. The stream is closed
+    // by releasing all references to the returned object.
+    virtual status_t openOutputStream(
+            audio_io_handle_t handle,
+            audio_devices_t devices,
+            audio_output_flags_t flags,
+            struct audio_config *config,
+            const char *address,
+            sp<StreamOutHalInterface> *outStream);
+
+    // Creates and opens the audio hardware input stream. The stream is closed
+    // by releasing all references to the returned object.
+    virtual status_t openInputStream(
+            audio_io_handle_t handle,
+            audio_devices_t devices,
+            struct audio_config *config,
+            audio_input_flags_t flags,
+            const char *address,
+            audio_source_t source,
+            sp<StreamInHalInterface> *inStream);
+
+    // Returns whether createAudioPatch and releaseAudioPatch operations are supported.
+    virtual status_t supportsAudioPatches(bool *supportsPatches);
+
+    // Creates an audio patch between several source and sink ports.
+    virtual status_t createAudioPatch(
+            unsigned int num_sources,
+            const struct audio_port_config *sources,
+            unsigned int num_sinks,
+            const struct audio_port_config *sinks,
+            audio_patch_handle_t *patch);
+
+    // Releases an audio patch.
+    virtual status_t releaseAudioPatch(audio_patch_handle_t patch);
+
+    // Fills the list of supported attributes for a given audio port.
+    virtual status_t getAudioPort(struct audio_port *port);
+
+    // Set audio port configuration.
+    virtual status_t setAudioPortConfig(const struct audio_port_config *config);
+
+    virtual status_t dump(int fd);
+
+    void closeOutputStream(struct audio_stream_out *stream_out);
+    void closeInputStream(struct audio_stream_in *stream_in);
+
+  private:
+    audio_hw_device_t *mDev;
+
+    friend class DevicesFactoryHalLocal;
+
+    // Can not be constructed directly by clients.
+    explicit DeviceHalLocal(audio_hw_device_t *dev);
+
+    // The destructor automatically closes the device.
+    virtual ~DeviceHalLocal();
+
+    uint32_t version() const { return mDev->common.version; }
+};
+
+} // namespace android
+
+#endif // ANDROID_HARDWARE_DEVICE_HAL_LOCAL_H
diff --git a/media/libaudiohal/4.0/DevicesFactoryHalHidl.cpp b/media/libaudiohal/4.0/DevicesFactoryHalHidl.cpp
new file mode 100644
index 0000000..5b33592
--- /dev/null
+++ b/media/libaudiohal/4.0/DevicesFactoryHalHidl.cpp
@@ -0,0 +1,98 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#include <string.h>
+
+#define LOG_TAG "DevicesFactoryHalHidl"
+//#define LOG_NDEBUG 0
+
+#include <android/hardware/audio/2.0/IDevice.h>
+#include <media/audiohal/hidl/HalDeathHandler.h>
+#include <utils/Log.h>
+
+#include "ConversionHelperHidl.h"
+#include "DeviceHalHidl.h"
+#include "DevicesFactoryHalHidl.h"
+
+using ::android::hardware::audio::V2_0::IDevice;
+using ::android::hardware::audio::V2_0::Result;
+using ::android::hardware::Return;
+
+namespace android {
+
+DevicesFactoryHalHidl::DevicesFactoryHalHidl() {
+    mDevicesFactory = IDevicesFactory::getService();
+    if (mDevicesFactory != 0) {
+        // It is assumed that DevicesFactory is owned by AudioFlinger
+        // and thus have the same lifespan.
+        mDevicesFactory->linkToDeath(HalDeathHandler::getInstance(), 0 /*cookie*/);
+    } else {
+        ALOGE("Failed to obtain IDevicesFactory service, terminating process.");
+        exit(1);
+    }
+    // The MSD factory is optional
+    mDevicesFactoryMsd = IDevicesFactory::getService(AUDIO_HAL_SERVICE_NAME_MSD);
+    // TODO: Register death handler, and add 'restart' directive to audioserver.rc
+}
+
+DevicesFactoryHalHidl::~DevicesFactoryHalHidl() {
+}
+
+// static
+status_t DevicesFactoryHalHidl::nameFromHal(const char *name, IDevicesFactory::Device *device) {
+    if (strcmp(name, AUDIO_HARDWARE_MODULE_ID_PRIMARY) == 0) {
+        *device = IDevicesFactory::Device::PRIMARY;
+        return OK;
+    } else if(strcmp(name, AUDIO_HARDWARE_MODULE_ID_A2DP) == 0) {
+        *device = IDevicesFactory::Device::A2DP;
+        return OK;
+    } else if(strcmp(name, AUDIO_HARDWARE_MODULE_ID_USB) == 0) {
+        *device = IDevicesFactory::Device::USB;
+        return OK;
+    } else if(strcmp(name, AUDIO_HARDWARE_MODULE_ID_REMOTE_SUBMIX) == 0) {
+        *device = IDevicesFactory::Device::R_SUBMIX;
+        return OK;
+    } else if(strcmp(name, AUDIO_HARDWARE_MODULE_ID_STUB) == 0) {
+        *device = IDevicesFactory::Device::STUB;
+        return OK;
+    }
+    ALOGE("Invalid device name %s", name);
+    return BAD_VALUE;
+}
+
+status_t DevicesFactoryHalHidl::openDevice(const char *name, sp<DeviceHalInterface> *device) {
+    if (mDevicesFactory == 0) return NO_INIT;
+    IDevicesFactory::Device hidlDevice;
+    status_t status = nameFromHal(name, &hidlDevice);
+    if (status != OK) return status;
+    Result retval = Result::NOT_INITIALIZED;
+    Return<void> ret = mDevicesFactory->openDevice(
+            hidlDevice,
+            [&](Result r, const sp<IDevice>& result) {
+                retval = r;
+                if (retval == Result::OK) {
+                    *device = new DeviceHalHidl(result);
+                }
+            });
+    if (ret.isOk()) {
+        if (retval == Result::OK) return OK;
+        else if (retval == Result::INVALID_ARGUMENTS) return BAD_VALUE;
+        else return NO_INIT;
+    }
+    return FAILED_TRANSACTION;
+}
+
+} // namespace android
diff --git a/media/libaudiohal/4.0/DevicesFactoryHalHidl.h b/media/libaudiohal/4.0/DevicesFactoryHalHidl.h
new file mode 100644
index 0000000..0748849
--- /dev/null
+++ b/media/libaudiohal/4.0/DevicesFactoryHalHidl.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#ifndef ANDROID_HARDWARE_DEVICES_FACTORY_HAL_HIDL_H
+#define ANDROID_HARDWARE_DEVICES_FACTORY_HAL_HIDL_H
+
+#include <android/hardware/audio/2.0/IDevicesFactory.h>
+#include <media/audiohal/DevicesFactoryHalInterface.h>
+#include <utils/Errors.h>
+#include <utils/RefBase.h>
+
+#include "DeviceHalHidl.h"
+
+using ::android::hardware::audio::V2_0::IDevicesFactory;
+
+namespace android {
+
+class DevicesFactoryHalHidl : public DevicesFactoryHalInterface
+{
+  public:
+    // Opens a device with the specified name. To close the device, it is
+    // necessary to release references to the returned object.
+    virtual status_t openDevice(const char *name, sp<DeviceHalInterface> *device);
+
+  private:
+    friend class DevicesFactoryHalHybrid;
+
+    sp<IDevicesFactory> mDevicesFactory;
+    sp<IDevicesFactory> mDevicesFactoryMsd;
+
+    static status_t nameFromHal(const char *name, IDevicesFactory::Device *device);
+
+    // Can not be constructed directly by clients.
+    DevicesFactoryHalHidl();
+
+    virtual ~DevicesFactoryHalHidl();
+};
+
+} // namespace android
+
+#endif // ANDROID_HARDWARE_DEVICES_FACTORY_HAL_HIDL_H
diff --git a/media/libaudiohal/4.0/DevicesFactoryHalHybrid.cpp b/media/libaudiohal/4.0/DevicesFactoryHalHybrid.cpp
new file mode 100644
index 0000000..77df6b5
--- /dev/null
+++ b/media/libaudiohal/4.0/DevicesFactoryHalHybrid.cpp
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+#define LOG_TAG "DevicesFactoryHalHybrid"
+//#define LOG_NDEBUG 0
+
+#include "DevicesFactoryHalHybrid.h"
+#include "DevicesFactoryHalLocal.h"
+#include "DevicesFactoryHalHidl.h"
+
+namespace android {
+
+DevicesFactoryHalHybrid::DevicesFactoryHalHybrid()
+        : mLocalFactory(new DevicesFactoryHalLocal()),
+          mHidlFactory(new DevicesFactoryHalHidl()) {
+}
+
+DevicesFactoryHalHybrid::~DevicesFactoryHalHybrid() {
+}
+
+status_t DevicesFactoryHalHybrid::openDevice(const char *name, sp<DeviceHalInterface> *device) {
+    if (mHidlFactory != 0 && strcmp(AUDIO_HARDWARE_MODULE_ID_A2DP, name) != 0) {
+        return mHidlFactory->openDevice(name, device);
+    }
+    return mLocalFactory->openDevice(name, device);
+}
+
+} // namespace android
diff --git a/media/libaudiohal/4.0/DevicesFactoryHalHybrid.h b/media/libaudiohal/4.0/DevicesFactoryHalHybrid.h
new file mode 100644
index 0000000..abd57d6
--- /dev/null
+++ b/media/libaudiohal/4.0/DevicesFactoryHalHybrid.h
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+#ifndef ANDROID_HARDWARE_DEVICES_FACTORY_HAL_HYBRID_H
+#define ANDROID_HARDWARE_DEVICES_FACTORY_HAL_HYBRID_H
+
+#include <media/audiohal/DevicesFactoryHalInterface.h>
+#include <utils/Errors.h>
+#include <utils/RefBase.h>
+
+namespace android {
+
+class DevicesFactoryHalHybrid : public DevicesFactoryHalInterface
+{
+  public:
+    // Opens a device with the specified name. To close the device, it is
+    // necessary to release references to the returned object.
+    virtual status_t openDevice(const char *name, sp<DeviceHalInterface> *device);
+
+  private:
+    friend class DevicesFactoryHalInterface;
+
+    // Can not be constructed directly by clients.
+    DevicesFactoryHalHybrid();
+
+    virtual ~DevicesFactoryHalHybrid();
+
+    sp<DevicesFactoryHalInterface> mLocalFactory;
+    sp<DevicesFactoryHalInterface> mHidlFactory;
+};
+
+} // namespace android
+
+#endif // ANDROID_HARDWARE_DEVICES_FACTORY_HAL_HYBRID_H
diff --git a/media/libaudiohal/4.0/DevicesFactoryHalLocal.cpp b/media/libaudiohal/4.0/DevicesFactoryHalLocal.cpp
new file mode 100644
index 0000000..13a9acd
--- /dev/null
+++ b/media/libaudiohal/4.0/DevicesFactoryHalLocal.cpp
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#define LOG_TAG "DevicesFactoryHalLocal"
+//#define LOG_NDEBUG 0
+
+#include <string.h>
+
+#include <hardware/audio.h>
+#include <utils/Log.h>
+
+#include "DeviceHalLocal.h"
+#include "DevicesFactoryHalLocal.h"
+
+namespace android {
+
+static status_t load_audio_interface(const char *if_name, audio_hw_device_t **dev)
+{
+    const hw_module_t *mod;
+    int rc;
+
+    rc = hw_get_module_by_class(AUDIO_HARDWARE_MODULE_ID, if_name, &mod);
+    if (rc) {
+        ALOGE("%s couldn't load audio hw module %s.%s (%s)", __func__,
+                AUDIO_HARDWARE_MODULE_ID, if_name, strerror(-rc));
+        goto out;
+    }
+    rc = audio_hw_device_open(mod, dev);
+    if (rc) {
+        ALOGE("%s couldn't open audio hw device in %s.%s (%s)", __func__,
+                AUDIO_HARDWARE_MODULE_ID, if_name, strerror(-rc));
+        goto out;
+    }
+    if ((*dev)->common.version < AUDIO_DEVICE_API_VERSION_MIN) {
+        ALOGE("%s wrong audio hw device version %04x", __func__, (*dev)->common.version);
+        rc = BAD_VALUE;
+        audio_hw_device_close(*dev);
+        goto out;
+    }
+    return OK;
+
+out:
+    *dev = NULL;
+    return rc;
+}
+
+status_t DevicesFactoryHalLocal::openDevice(const char *name, sp<DeviceHalInterface> *device) {
+    audio_hw_device_t *dev;
+    status_t rc = load_audio_interface(name, &dev);
+    if (rc == OK) {
+        *device = new DeviceHalLocal(dev);
+    }
+    return rc;
+}
+
+} // namespace android
diff --git a/media/libaudiohal/4.0/DevicesFactoryHalLocal.h b/media/libaudiohal/4.0/DevicesFactoryHalLocal.h
new file mode 100644
index 0000000..b9d18ab
--- /dev/null
+++ b/media/libaudiohal/4.0/DevicesFactoryHalLocal.h
@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#ifndef ANDROID_HARDWARE_DEVICES_FACTORY_HAL_LOCAL_H
+#define ANDROID_HARDWARE_DEVICES_FACTORY_HAL_LOCAL_H
+
+#include <media/audiohal/DevicesFactoryHalInterface.h>
+#include <utils/Errors.h>
+#include <utils/RefBase.h>
+
+#include "DeviceHalLocal.h"
+
+namespace android {
+
+class DevicesFactoryHalLocal : public DevicesFactoryHalInterface
+{
+  public:
+    // Opens a device with the specified name. To close the device, it is
+    // necessary to release references to the returned object.
+    virtual status_t openDevice(const char *name, sp<DeviceHalInterface> *device);
+
+  private:
+    friend class DevicesFactoryHalHybrid;
+
+    // Can not be constructed directly by clients.
+    DevicesFactoryHalLocal() {}
+
+    virtual ~DevicesFactoryHalLocal() {}
+};
+
+} // namespace android
+
+#endif // ANDROID_HARDWARE_DEVICES_FACTORY_HAL_LOCAL_H
diff --git a/media/libaudiohal/4.0/EffectBufferHalHidl.cpp b/media/libaudiohal/4.0/EffectBufferHalHidl.cpp
new file mode 100644
index 0000000..226a500
--- /dev/null
+++ b/media/libaudiohal/4.0/EffectBufferHalHidl.cpp
@@ -0,0 +1,144 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+#include <atomic>
+
+#define LOG_TAG "EffectBufferHalHidl"
+//#define LOG_NDEBUG 0
+
+#include <android/hidl/allocator/1.0/IAllocator.h>
+#include <hidlmemory/mapping.h>
+#include <utils/Log.h>
+
+#include "ConversionHelperHidl.h"
+#include "EffectBufferHalHidl.h"
+
+using ::android::hardware::Return;
+using ::android::hidl::allocator::V1_0::IAllocator;
+
+namespace android {
+
+// static
+uint64_t EffectBufferHalHidl::makeUniqueId() {
+    static std::atomic<uint64_t> counter{1};
+    return counter++;
+}
+
+status_t EffectBufferHalHidl::allocate(
+        size_t size, sp<EffectBufferHalInterface>* buffer) {
+    return mirror(nullptr, size, buffer);
+}
+
+status_t EffectBufferHalHidl::mirror(
+        void* external, size_t size, sp<EffectBufferHalInterface>* buffer) {
+    sp<EffectBufferHalInterface> tempBuffer = new EffectBufferHalHidl(size);
+    status_t result = static_cast<EffectBufferHalHidl*>(tempBuffer.get())->init();
+    if (result == OK) {
+        tempBuffer->setExternalData(external);
+        *buffer = tempBuffer;
+    }
+    return result;
+}
+
+EffectBufferHalHidl::EffectBufferHalHidl(size_t size)
+        : mBufferSize(size), mFrameCountChanged(false),
+          mExternalData(nullptr), mAudioBuffer{0, {nullptr}} {
+    mHidlBuffer.id = makeUniqueId();
+    mHidlBuffer.frameCount = 0;
+}
+
+EffectBufferHalHidl::~EffectBufferHalHidl() {
+}
+
+status_t EffectBufferHalHidl::init() {
+    sp<IAllocator> ashmem = IAllocator::getService("ashmem");
+    if (ashmem == 0) {
+        ALOGE("Failed to retrieve ashmem allocator service");
+        return NO_INIT;
+    }
+    status_t retval = NO_MEMORY;
+    Return<void> result = ashmem->allocate(
+            mBufferSize,
+            [&](bool success, const hidl_memory& memory) {
+                if (success) {
+                    mHidlBuffer.data = memory;
+                    retval = OK;
+                }
+            });
+    if (result.isOk() && retval == OK) {
+        mMemory = hardware::mapMemory(mHidlBuffer.data);
+        if (mMemory != 0) {
+            mMemory->update();
+            mAudioBuffer.raw = static_cast<void*>(mMemory->getPointer());
+            memset(mAudioBuffer.raw, 0, mMemory->getSize());
+            mMemory->commit();
+        } else {
+            ALOGE("Failed to map allocated ashmem");
+            retval = NO_MEMORY;
+        }
+    } else {
+        ALOGE("Failed to allocate %d bytes from ashmem", (int)mBufferSize);
+    }
+    return result.isOk() ? retval : FAILED_TRANSACTION;
+}
+
+audio_buffer_t* EffectBufferHalHidl::audioBuffer() {
+    return &mAudioBuffer;
+}
+
+void* EffectBufferHalHidl::externalData() const {
+    return mExternalData;
+}
+
+void EffectBufferHalHidl::setFrameCount(size_t frameCount) {
+    mHidlBuffer.frameCount = frameCount;
+    mAudioBuffer.frameCount = frameCount;
+    mFrameCountChanged = true;
+}
+
+bool EffectBufferHalHidl::checkFrameCountChange() {
+    bool result = mFrameCountChanged;
+    mFrameCountChanged = false;
+    return result;
+}
+
+void EffectBufferHalHidl::setExternalData(void* external) {
+    mExternalData = external;
+}
+
+void EffectBufferHalHidl::update() {
+    update(mBufferSize);
+}
+
+void EffectBufferHalHidl::commit() {
+    commit(mBufferSize);
+}
+
+void EffectBufferHalHidl::update(size_t size) {
+    if (mExternalData == nullptr) return;
+    mMemory->update();
+    if (size > mBufferSize) size = mBufferSize;
+    memcpy(mAudioBuffer.raw, mExternalData, size);
+    mMemory->commit();
+}
+
+void EffectBufferHalHidl::commit(size_t size) {
+    if (mExternalData == nullptr) return;
+    if (size > mBufferSize) size = mBufferSize;
+    memcpy(mExternalData, mAudioBuffer.raw, size);
+}
+
+} // namespace android
diff --git a/media/libaudiohal/4.0/EffectBufferHalHidl.h b/media/libaudiohal/4.0/EffectBufferHalHidl.h
new file mode 100644
index 0000000..31e0087
--- /dev/null
+++ b/media/libaudiohal/4.0/EffectBufferHalHidl.h
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+#ifndef ANDROID_HARDWARE_EFFECT_BUFFER_HAL_HIDL_H
+#define ANDROID_HARDWARE_EFFECT_BUFFER_HAL_HIDL_H
+
+#include <android/hardware/audio/effect/2.0/types.h>
+#include <android/hidl/memory/1.0/IMemory.h>
+#include <hidl/HidlSupport.h>
+#include <media/audiohal/EffectBufferHalInterface.h>
+#include <system/audio_effect.h>
+
+using android::hardware::audio::effect::V2_0::AudioBuffer;
+using android::hardware::hidl_memory;
+using android::hidl::memory::V1_0::IMemory;
+
+namespace android {
+
+class EffectBufferHalHidl : public EffectBufferHalInterface
+{
+  public:
+    static status_t allocate(size_t size, sp<EffectBufferHalInterface>* buffer);
+    static status_t mirror(void* external, size_t size, sp<EffectBufferHalInterface>* buffer);
+
+    virtual audio_buffer_t* audioBuffer();
+    virtual void* externalData() const;
+
+    virtual size_t getSize() const override { return mBufferSize; }
+
+    virtual void setExternalData(void* external);
+    virtual void setFrameCount(size_t frameCount);
+    virtual bool checkFrameCountChange();
+
+    virtual void update();
+    virtual void commit();
+    virtual void update(size_t size);
+    virtual void commit(size_t size);
+
+    const AudioBuffer& hidlBuffer() const { return mHidlBuffer; }
+
+  private:
+    friend class EffectBufferHalInterface;
+
+    static uint64_t makeUniqueId();
+
+    const size_t mBufferSize;
+    bool mFrameCountChanged;
+    void* mExternalData;
+    AudioBuffer mHidlBuffer;
+    sp<IMemory> mMemory;
+    audio_buffer_t mAudioBuffer;
+
+    // Can not be constructed directly by clients.
+    explicit EffectBufferHalHidl(size_t size);
+
+    virtual ~EffectBufferHalHidl();
+
+    status_t init();
+};
+
+} // namespace android
+
+#endif // ANDROID_HARDWARE_EFFECT_BUFFER_HAL_HIDL_H
diff --git a/media/libaudiohal/4.0/EffectHalHidl.cpp b/media/libaudiohal/4.0/EffectHalHidl.cpp
new file mode 100644
index 0000000..4fb032c
--- /dev/null
+++ b/media/libaudiohal/4.0/EffectHalHidl.cpp
@@ -0,0 +1,338 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#define LOG_TAG "EffectHalHidl"
+//#define LOG_NDEBUG 0
+
+#include <hwbinder/IPCThreadState.h>
+#include <media/EffectsFactoryApi.h>
+#include <utils/Log.h>
+
+#include "ConversionHelperHidl.h"
+#include "EffectBufferHalHidl.h"
+#include "EffectHalHidl.h"
+#include "HidlUtils.h"
+
+using ::android::hardware::audio::effect::V2_0::AudioBuffer;
+using ::android::hardware::audio::effect::V2_0::EffectBufferAccess;
+using ::android::hardware::audio::effect::V2_0::EffectConfigParameters;
+using ::android::hardware::audio::effect::V2_0::MessageQueueFlagBits;
+using ::android::hardware::audio::effect::V2_0::Result;
+using ::android::hardware::audio::common::V2_0::HidlUtils;
+using ::android::hardware::audio::common::V2_0::AudioChannelMask;
+using ::android::hardware::audio::common::V2_0::AudioFormat;
+using ::android::hardware::hidl_vec;
+using ::android::hardware::MQDescriptorSync;
+using ::android::hardware::Return;
+
+namespace android {
+
+EffectHalHidl::EffectHalHidl(const sp<IEffect>& effect, uint64_t effectId)
+        : mEffect(effect), mEffectId(effectId), mBuffersChanged(true), mEfGroup(nullptr) {
+}
+
+EffectHalHidl::~EffectHalHidl() {
+    if (mEffect != 0) {
+        close();
+        mEffect.clear();
+        hardware::IPCThreadState::self()->flushCommands();
+    }
+    if (mEfGroup) {
+        EventFlag::deleteEventFlag(&mEfGroup);
+    }
+}
+
+// static
+void EffectHalHidl::effectDescriptorToHal(
+        const EffectDescriptor& descriptor, effect_descriptor_t* halDescriptor) {
+    HidlUtils::uuidToHal(descriptor.type, &halDescriptor->type);
+    HidlUtils::uuidToHal(descriptor.uuid, &halDescriptor->uuid);
+    halDescriptor->flags = static_cast<uint32_t>(descriptor.flags);
+    halDescriptor->cpuLoad = descriptor.cpuLoad;
+    halDescriptor->memoryUsage = descriptor.memoryUsage;
+    memcpy(halDescriptor->name, descriptor.name.data(), descriptor.name.size());
+    memcpy(halDescriptor->implementor,
+            descriptor.implementor.data(), descriptor.implementor.size());
+}
+
+// TODO(mnaganov): These buffer conversion functions should be shared with Effect wrapper
+// via HidlUtils. Move them there when hardware/interfaces will get un-frozen again.
+
+// static
+void EffectHalHidl::effectBufferConfigFromHal(
+        const buffer_config_t& halConfig, EffectBufferConfig* config) {
+    config->samplingRateHz = halConfig.samplingRate;
+    config->channels = AudioChannelMask(halConfig.channels);
+    config->format = AudioFormat(halConfig.format);
+    config->accessMode = EffectBufferAccess(halConfig.accessMode);
+    config->mask = EffectConfigParameters(halConfig.mask);
+}
+
+// static
+void EffectHalHidl::effectBufferConfigToHal(
+        const EffectBufferConfig& config, buffer_config_t* halConfig) {
+    halConfig->buffer.frameCount = 0;
+    halConfig->buffer.raw = NULL;
+    halConfig->samplingRate = config.samplingRateHz;
+    halConfig->channels = static_cast<uint32_t>(config.channels);
+    halConfig->bufferProvider.cookie = NULL;
+    halConfig->bufferProvider.getBuffer = NULL;
+    halConfig->bufferProvider.releaseBuffer = NULL;
+    halConfig->format = static_cast<uint8_t>(config.format);
+    halConfig->accessMode = static_cast<uint8_t>(config.accessMode);
+    halConfig->mask = static_cast<uint8_t>(config.mask);
+}
+
+// static
+void EffectHalHidl::effectConfigFromHal(const effect_config_t& halConfig, EffectConfig* config) {
+    effectBufferConfigFromHal(halConfig.inputCfg, &config->inputCfg);
+    effectBufferConfigFromHal(halConfig.outputCfg, &config->outputCfg);
+}
+
+// static
+void EffectHalHidl::effectConfigToHal(const EffectConfig& config, effect_config_t* halConfig) {
+    effectBufferConfigToHal(config.inputCfg, &halConfig->inputCfg);
+    effectBufferConfigToHal(config.outputCfg, &halConfig->outputCfg);
+}
+
+// static
+status_t EffectHalHidl::analyzeResult(const Result& result) {
+    switch (result) {
+        case Result::OK: return OK;
+        case Result::INVALID_ARGUMENTS: return BAD_VALUE;
+        case Result::INVALID_STATE: return NOT_ENOUGH_DATA;
+        case Result::NOT_INITIALIZED: return NO_INIT;
+        case Result::NOT_SUPPORTED: return INVALID_OPERATION;
+        case Result::RESULT_TOO_BIG: return NO_MEMORY;
+        default: return NO_INIT;
+    }
+}
+
+status_t EffectHalHidl::setInBuffer(const sp<EffectBufferHalInterface>& buffer) {
+    if (!mBuffersChanged) {
+        if (buffer.get() == nullptr || mInBuffer.get() == nullptr) {
+            mBuffersChanged = buffer.get() != mInBuffer.get();
+        } else {
+            mBuffersChanged = buffer->audioBuffer() != mInBuffer->audioBuffer();
+        }
+    }
+    mInBuffer = buffer;
+    return OK;
+}
+
+status_t EffectHalHidl::setOutBuffer(const sp<EffectBufferHalInterface>& buffer) {
+    if (!mBuffersChanged) {
+        if (buffer.get() == nullptr || mOutBuffer.get() == nullptr) {
+            mBuffersChanged = buffer.get() != mOutBuffer.get();
+        } else {
+            mBuffersChanged = buffer->audioBuffer() != mOutBuffer->audioBuffer();
+        }
+    }
+    mOutBuffer = buffer;
+    return OK;
+}
+
+status_t EffectHalHidl::process() {
+    return processImpl(static_cast<uint32_t>(MessageQueueFlagBits::REQUEST_PROCESS));
+}
+
+status_t EffectHalHidl::processReverse() {
+    return processImpl(static_cast<uint32_t>(MessageQueueFlagBits::REQUEST_PROCESS_REVERSE));
+}
+
+status_t EffectHalHidl::prepareForProcessing() {
+    std::unique_ptr<StatusMQ> tempStatusMQ;
+    Result retval;
+    Return<void> ret = mEffect->prepareForProcessing(
+            [&](Result r, const MQDescriptorSync<Result>& statusMQ) {
+                retval = r;
+                if (retval == Result::OK) {
+                    tempStatusMQ.reset(new StatusMQ(statusMQ));
+                    if (tempStatusMQ->isValid() && tempStatusMQ->getEventFlagWord()) {
+                        EventFlag::createEventFlag(tempStatusMQ->getEventFlagWord(), &mEfGroup);
+                    }
+                }
+            });
+    if (!ret.isOk() || retval != Result::OK) {
+        return ret.isOk() ? analyzeResult(retval) : FAILED_TRANSACTION;
+    }
+    if (!tempStatusMQ || !tempStatusMQ->isValid() || !mEfGroup) {
+        ALOGE_IF(!tempStatusMQ, "Failed to obtain status message queue for effects");
+        ALOGE_IF(tempStatusMQ && !tempStatusMQ->isValid(),
+                "Status message queue for effects is invalid");
+        ALOGE_IF(!mEfGroup, "Event flag creation for effects failed");
+        return NO_INIT;
+    }
+    mStatusMQ = std::move(tempStatusMQ);
+    return OK;
+}
+
+bool EffectHalHidl::needToResetBuffers() {
+    if (mBuffersChanged) return true;
+    bool inBufferFrameCountUpdated = mInBuffer->checkFrameCountChange();
+    bool outBufferFrameCountUpdated = mOutBuffer->checkFrameCountChange();
+    return inBufferFrameCountUpdated || outBufferFrameCountUpdated;
+}
+
+status_t EffectHalHidl::processImpl(uint32_t mqFlag) {
+    if (mEffect == 0 || mInBuffer == 0 || mOutBuffer == 0) return NO_INIT;
+    status_t status;
+    if (!mStatusMQ && (status = prepareForProcessing()) != OK) {
+        return status;
+    }
+    if (needToResetBuffers() && (status = setProcessBuffers()) != OK) {
+        return status;
+    }
+    // The data is already in the buffers, just need to flush it and wake up the server side.
+    std::atomic_thread_fence(std::memory_order_release);
+    mEfGroup->wake(mqFlag);
+    uint32_t efState = 0;
+retry:
+    status_t ret = mEfGroup->wait(
+            static_cast<uint32_t>(MessageQueueFlagBits::DONE_PROCESSING), &efState);
+    if (efState & static_cast<uint32_t>(MessageQueueFlagBits::DONE_PROCESSING)) {
+        Result retval = Result::NOT_INITIALIZED;
+        mStatusMQ->read(&retval);
+        if (retval == Result::OK || retval == Result::INVALID_STATE) {
+            // Sync back the changed contents of the buffer.
+            std::atomic_thread_fence(std::memory_order_acquire);
+        }
+        return analyzeResult(retval);
+    }
+    if (ret == -EAGAIN || ret == -EINTR) {
+        // Spurious wakeup. This normally retries no more than once.
+        goto retry;
+    }
+    return ret;
+}
+
+status_t EffectHalHidl::setProcessBuffers() {
+    Return<Result> ret = mEffect->setProcessBuffers(
+            static_cast<EffectBufferHalHidl*>(mInBuffer.get())->hidlBuffer(),
+            static_cast<EffectBufferHalHidl*>(mOutBuffer.get())->hidlBuffer());
+    if (ret.isOk() && ret == Result::OK) {
+        mBuffersChanged = false;
+        return OK;
+    }
+    return ret.isOk() ? analyzeResult(ret) : FAILED_TRANSACTION;
+}
+
+status_t EffectHalHidl::command(uint32_t cmdCode, uint32_t cmdSize, void *pCmdData,
+        uint32_t *replySize, void *pReplyData) {
+    if (mEffect == 0) return NO_INIT;
+
+    // Special cases.
+    if (cmdCode == EFFECT_CMD_SET_CONFIG || cmdCode == EFFECT_CMD_SET_CONFIG_REVERSE) {
+        return setConfigImpl(cmdCode, cmdSize, pCmdData, replySize, pReplyData);
+    } else if (cmdCode == EFFECT_CMD_GET_CONFIG || cmdCode == EFFECT_CMD_GET_CONFIG_REVERSE) {
+        return getConfigImpl(cmdCode, replySize, pReplyData);
+    }
+
+    // Common case.
+    hidl_vec<uint8_t> hidlData;
+    if (pCmdData != nullptr && cmdSize > 0) {
+        hidlData.setToExternal(reinterpret_cast<uint8_t*>(pCmdData), cmdSize);
+    }
+    status_t status;
+    uint32_t replySizeStub = 0;
+    if (replySize == nullptr || pReplyData == nullptr) replySize = &replySizeStub;
+    Return<void> ret = mEffect->command(cmdCode, hidlData, *replySize,
+            [&](int32_t s, const hidl_vec<uint8_t>& result) {
+                status = s;
+                if (status == 0) {
+                    if (*replySize > result.size()) *replySize = result.size();
+                    if (pReplyData != nullptr && *replySize > 0) {
+                        memcpy(pReplyData, &result[0], *replySize);
+                    }
+                }
+            });
+    return ret.isOk() ? status : FAILED_TRANSACTION;
+}
+
+status_t EffectHalHidl::getDescriptor(effect_descriptor_t *pDescriptor) {
+    if (mEffect == 0) return NO_INIT;
+    Result retval = Result::NOT_INITIALIZED;
+    Return<void> ret = mEffect->getDescriptor(
+            [&](Result r, const EffectDescriptor& result) {
+                retval = r;
+                if (retval == Result::OK) {
+                    effectDescriptorToHal(result, pDescriptor);
+                }
+            });
+    return ret.isOk() ? analyzeResult(retval) : FAILED_TRANSACTION;
+}
+
+status_t EffectHalHidl::close() {
+    if (mEffect == 0) return NO_INIT;
+    Return<Result> ret = mEffect->close();
+    return ret.isOk() ? analyzeResult(ret) : FAILED_TRANSACTION;
+}
+
+status_t EffectHalHidl::getConfigImpl(
+        uint32_t cmdCode, uint32_t *replySize, void *pReplyData) {
+    if (replySize == NULL || *replySize != sizeof(effect_config_t) || pReplyData == NULL) {
+        return BAD_VALUE;
+    }
+    status_t result = FAILED_TRANSACTION;
+    Return<void> ret;
+    if (cmdCode == EFFECT_CMD_GET_CONFIG) {
+        ret = mEffect->getConfig([&] (Result r, const EffectConfig &hidlConfig) {
+            result = analyzeResult(r);
+            if (r == Result::OK) {
+                effectConfigToHal(hidlConfig, static_cast<effect_config_t*>(pReplyData));
+            }
+        });
+    } else {
+        ret = mEffect->getConfigReverse([&] (Result r, const EffectConfig &hidlConfig) {
+            result = analyzeResult(r);
+            if (r == Result::OK) {
+                effectConfigToHal(hidlConfig, static_cast<effect_config_t*>(pReplyData));
+            }
+        });
+    }
+    if (!ret.isOk()) {
+        result = FAILED_TRANSACTION;
+    }
+    return result;
+}
+
+status_t EffectHalHidl::setConfigImpl(
+        uint32_t cmdCode, uint32_t cmdSize, void *pCmdData, uint32_t *replySize, void *pReplyData) {
+    if (pCmdData == NULL || cmdSize != sizeof(effect_config_t) ||
+            replySize == NULL || *replySize != sizeof(int32_t) || pReplyData == NULL) {
+        return BAD_VALUE;
+    }
+    const effect_config_t *halConfig = static_cast<effect_config_t*>(pCmdData);
+    if (halConfig->inputCfg.bufferProvider.getBuffer != NULL ||
+            halConfig->inputCfg.bufferProvider.releaseBuffer != NULL ||
+            halConfig->outputCfg.bufferProvider.getBuffer != NULL ||
+            halConfig->outputCfg.bufferProvider.releaseBuffer != NULL) {
+        ALOGE("Buffer provider callbacks are not supported");
+    }
+    EffectConfig hidlConfig;
+    effectConfigFromHal(*halConfig, &hidlConfig);
+    Return<Result> ret = cmdCode == EFFECT_CMD_SET_CONFIG ?
+            mEffect->setConfig(hidlConfig, nullptr, nullptr) :
+            mEffect->setConfigReverse(hidlConfig, nullptr, nullptr);
+    status_t result = FAILED_TRANSACTION;
+    if (ret.isOk()) {
+        result = analyzeResult(ret);
+        *static_cast<int32_t*>(pReplyData) = result;
+    }
+    return result;
+}
+
+} // namespace android
diff --git a/media/libaudiohal/4.0/EffectHalHidl.h b/media/libaudiohal/4.0/EffectHalHidl.h
new file mode 100644
index 0000000..6ffdaf1
--- /dev/null
+++ b/media/libaudiohal/4.0/EffectHalHidl.h
@@ -0,0 +1,108 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#ifndef ANDROID_HARDWARE_EFFECT_HAL_HIDL_H
+#define ANDROID_HARDWARE_EFFECT_HAL_HIDL_H
+
+#include <android/hardware/audio/effect/2.0/IEffect.h>
+#include <media/audiohal/EffectHalInterface.h>
+#include <fmq/EventFlag.h>
+#include <fmq/MessageQueue.h>
+#include <system/audio_effect.h>
+
+using ::android::hardware::audio::effect::V2_0::EffectBufferConfig;
+using ::android::hardware::audio::effect::V2_0::EffectConfig;
+using ::android::hardware::audio::effect::V2_0::EffectDescriptor;
+using ::android::hardware::audio::effect::V2_0::IEffect;
+using ::android::hardware::EventFlag;
+using ::android::hardware::MessageQueue;
+
+namespace android {
+
+class EffectHalHidl : public EffectHalInterface
+{
+  public:
+    // Set the input buffer.
+    virtual status_t setInBuffer(const sp<EffectBufferHalInterface>& buffer);
+
+    // Set the output buffer.
+    virtual status_t setOutBuffer(const sp<EffectBufferHalInterface>& buffer);
+
+    // Effect process function.
+    virtual status_t process();
+
+    // Process reverse stream function. This function is used to pass
+    // a reference stream to the effect engine.
+    virtual status_t processReverse();
+
+    // Send a command and receive a response to/from effect engine.
+    virtual status_t command(uint32_t cmdCode, uint32_t cmdSize, void *pCmdData,
+            uint32_t *replySize, void *pReplyData);
+
+    // Returns the effect descriptor.
+    virtual status_t getDescriptor(effect_descriptor_t *pDescriptor);
+
+    // Free resources on the remote side.
+    virtual status_t close();
+
+    // Whether it's a local implementation.
+    virtual bool isLocal() const { return false; }
+
+    uint64_t effectId() const { return mEffectId; }
+
+    static void effectDescriptorToHal(
+            const EffectDescriptor& descriptor, effect_descriptor_t* halDescriptor);
+
+  private:
+    friend class EffectsFactoryHalHidl;
+    typedef MessageQueue<
+        hardware::audio::effect::V2_0::Result, hardware::kSynchronizedReadWrite> StatusMQ;
+
+    sp<IEffect> mEffect;
+    const uint64_t mEffectId;
+    sp<EffectBufferHalInterface> mInBuffer;
+    sp<EffectBufferHalInterface> mOutBuffer;
+    bool mBuffersChanged;
+    std::unique_ptr<StatusMQ> mStatusMQ;
+    EventFlag* mEfGroup;
+
+    static status_t analyzeResult(const hardware::audio::effect::V2_0::Result& result);
+    static void effectBufferConfigFromHal(
+            const buffer_config_t& halConfig, EffectBufferConfig* config);
+    static void effectBufferConfigToHal(
+            const EffectBufferConfig& config, buffer_config_t* halConfig);
+    static void effectConfigFromHal(const effect_config_t& halConfig, EffectConfig* config);
+    static void effectConfigToHal(const EffectConfig& config, effect_config_t* halConfig);
+
+    // Can not be constructed directly by clients.
+    EffectHalHidl(const sp<IEffect>& effect, uint64_t effectId);
+
+    // The destructor automatically releases the effect.
+    virtual ~EffectHalHidl();
+
+    status_t getConfigImpl(uint32_t cmdCode, uint32_t *replySize, void *pReplyData);
+    status_t prepareForProcessing();
+    bool needToResetBuffers();
+    status_t processImpl(uint32_t mqFlag);
+    status_t setConfigImpl(
+            uint32_t cmdCode, uint32_t cmdSize, void *pCmdData,
+            uint32_t *replySize, void *pReplyData);
+    status_t setProcessBuffers();
+};
+
+} // namespace android
+
+#endif // ANDROID_HARDWARE_EFFECT_HAL_HIDL_H
diff --git a/media/libaudiohal/4.0/EffectsFactoryHalHidl.cpp b/media/libaudiohal/4.0/EffectsFactoryHalHidl.cpp
new file mode 100644
index 0000000..0d40e6d
--- /dev/null
+++ b/media/libaudiohal/4.0/EffectsFactoryHalHidl.cpp
@@ -0,0 +1,150 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#define LOG_TAG "EffectsFactoryHalHidl"
+//#define LOG_NDEBUG 0
+
+#include <cutils/native_handle.h>
+
+#include "ConversionHelperHidl.h"
+#include "EffectBufferHalHidl.h"
+#include "EffectHalHidl.h"
+#include "EffectsFactoryHalHidl.h"
+#include "HidlUtils.h"
+
+using ::android::hardware::audio::common::V2_0::HidlUtils;
+using ::android::hardware::audio::common::V2_0::Uuid;
+using ::android::hardware::audio::effect::V2_0::IEffect;
+using ::android::hardware::audio::effect::V2_0::Result;
+using ::android::hardware::Return;
+
+namespace android {
+
+EffectsFactoryHalHidl::EffectsFactoryHalHidl() : ConversionHelperHidl("EffectsFactory") {
+    mEffectsFactory = IEffectsFactory::getService();
+    if (mEffectsFactory == 0) {
+        ALOGE("Failed to obtain IEffectsFactory service, terminating process.");
+        exit(1);
+    }
+}
+
+EffectsFactoryHalHidl::~EffectsFactoryHalHidl() {
+}
+
+status_t EffectsFactoryHalHidl::queryAllDescriptors() {
+    if (mEffectsFactory == 0) return NO_INIT;
+    Result retval = Result::NOT_INITIALIZED;
+    Return<void> ret = mEffectsFactory->getAllDescriptors(
+            [&](Result r, const hidl_vec<EffectDescriptor>& result) {
+                retval = r;
+                if (retval == Result::OK) {
+                    mLastDescriptors = result;
+                }
+            });
+    if (ret.isOk()) {
+        return retval == Result::OK ? OK : NO_INIT;
+    }
+    mLastDescriptors.resize(0);
+    return processReturn(__FUNCTION__, ret);
+}
+
+status_t EffectsFactoryHalHidl::queryNumberEffects(uint32_t *pNumEffects) {
+    status_t queryResult = queryAllDescriptors();
+    if (queryResult == OK) {
+        *pNumEffects = mLastDescriptors.size();
+    }
+    return queryResult;
+}
+
+status_t EffectsFactoryHalHidl::getDescriptor(
+        uint32_t index, effect_descriptor_t *pDescriptor) {
+    // TODO: We need somehow to track the changes on the server side
+    // or figure out how to convert everybody to query all the descriptors at once.
+    // TODO: check for nullptr
+    if (mLastDescriptors.size() == 0) {
+        status_t queryResult = queryAllDescriptors();
+        if (queryResult != OK) return queryResult;
+    }
+    if (index >= mLastDescriptors.size()) return NAME_NOT_FOUND;
+    EffectHalHidl::effectDescriptorToHal(mLastDescriptors[index], pDescriptor);
+    return OK;
+}
+
+status_t EffectsFactoryHalHidl::getDescriptor(
+        const effect_uuid_t *pEffectUuid, effect_descriptor_t *pDescriptor) {
+    // TODO: check for nullptr
+    if (mEffectsFactory == 0) return NO_INIT;
+    Uuid hidlUuid;
+    HidlUtils::uuidFromHal(*pEffectUuid, &hidlUuid);
+    Result retval = Result::NOT_INITIALIZED;
+    Return<void> ret = mEffectsFactory->getDescriptor(hidlUuid,
+            [&](Result r, const EffectDescriptor& result) {
+                retval = r;
+                if (retval == Result::OK) {
+                    EffectHalHidl::effectDescriptorToHal(result, pDescriptor);
+                }
+            });
+    if (ret.isOk()) {
+        if (retval == Result::OK) return OK;
+        else if (retval == Result::INVALID_ARGUMENTS) return NAME_NOT_FOUND;
+        else return NO_INIT;
+    }
+    return processReturn(__FUNCTION__, ret);
+}
+
+status_t EffectsFactoryHalHidl::createEffect(
+        const effect_uuid_t *pEffectUuid, int32_t sessionId, int32_t ioId,
+        sp<EffectHalInterface> *effect) {
+    if (mEffectsFactory == 0) return NO_INIT;
+    Uuid hidlUuid;
+    HidlUtils::uuidFromHal(*pEffectUuid, &hidlUuid);
+    Result retval = Result::NOT_INITIALIZED;
+    Return<void> ret = mEffectsFactory->createEffect(
+            hidlUuid, sessionId, ioId,
+            [&](Result r, const sp<IEffect>& result, uint64_t effectId) {
+                retval = r;
+                if (retval == Result::OK) {
+                    *effect = new EffectHalHidl(result, effectId);
+                }
+            });
+    if (ret.isOk()) {
+        if (retval == Result::OK) return OK;
+        else if (retval == Result::INVALID_ARGUMENTS) return NAME_NOT_FOUND;
+        else return NO_INIT;
+    }
+    return processReturn(__FUNCTION__, ret);
+}
+
+status_t EffectsFactoryHalHidl::dumpEffects(int fd) {
+    if (mEffectsFactory == 0) return NO_INIT;
+    native_handle_t* hidlHandle = native_handle_create(1, 0);
+    hidlHandle->data[0] = fd;
+    Return<void> ret = mEffectsFactory->debugDump(hidlHandle);
+    native_handle_delete(hidlHandle);
+    return processReturn(__FUNCTION__, ret);
+}
+
+status_t EffectsFactoryHalHidl::allocateBuffer(size_t size, sp<EffectBufferHalInterface>* buffer) {
+    return EffectBufferHalHidl::allocate(size, buffer);
+}
+
+status_t EffectsFactoryHalHidl::mirrorBuffer(void* external, size_t size,
+                          sp<EffectBufferHalInterface>* buffer) {
+    return EffectBufferHalHidl::mirror(external, size, buffer);
+}
+
+
+} // namespace android
diff --git a/media/libaudiohal/4.0/EffectsFactoryHalHidl.h b/media/libaudiohal/4.0/EffectsFactoryHalHidl.h
new file mode 100644
index 0000000..82b5481
--- /dev/null
+++ b/media/libaudiohal/4.0/EffectsFactoryHalHidl.h
@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#ifndef ANDROID_HARDWARE_EFFECTS_FACTORY_HAL_HIDL_H
+#define ANDROID_HARDWARE_EFFECTS_FACTORY_HAL_HIDL_H
+
+#include <android/hardware/audio/effect/2.0/IEffectsFactory.h>
+#include <android/hardware/audio/effect/2.0/types.h>
+#include <media/audiohal/EffectsFactoryHalInterface.h>
+
+#include "ConversionHelperHidl.h"
+
+namespace android {
+
+using ::android::hardware::audio::effect::V2_0::EffectDescriptor;
+using ::android::hardware::audio::effect::V2_0::IEffectsFactory;
+using ::android::hardware::hidl_vec;
+
+class EffectsFactoryHalHidl : public EffectsFactoryHalInterface, public ConversionHelperHidl
+{
+  public:
+    // Returns the number of different effects in all loaded libraries.
+    virtual status_t queryNumberEffects(uint32_t *pNumEffects);
+
+    // Returns a descriptor of the next available effect.
+    virtual status_t getDescriptor(uint32_t index,
+            effect_descriptor_t *pDescriptor);
+
+    virtual status_t getDescriptor(const effect_uuid_t *pEffectUuid,
+            effect_descriptor_t *pDescriptor);
+
+    // Creates an effect engine of the specified type.
+    // To release the effect engine, it is necessary to release references
+    // to the returned effect object.
+    virtual status_t createEffect(const effect_uuid_t *pEffectUuid,
+            int32_t sessionId, int32_t ioId,
+            sp<EffectHalInterface> *effect);
+
+    virtual status_t dumpEffects(int fd);
+
+    status_t allocateBuffer(size_t size, sp<EffectBufferHalInterface>* buffer) override;
+    status_t mirrorBuffer(void* external, size_t size,
+                          sp<EffectBufferHalInterface>* buffer) override;
+
+  private:
+    friend class EffectsFactoryHalInterface;
+
+    sp<IEffectsFactory> mEffectsFactory;
+    hidl_vec<EffectDescriptor> mLastDescriptors;
+
+    // Can not be constructed directly by clients.
+    EffectsFactoryHalHidl();
+    virtual ~EffectsFactoryHalHidl();
+
+    status_t queryAllDescriptors();
+};
+
+} // namespace android
+
+#endif // ANDROID_HARDWARE_EFFECTS_FACTORY_HAL_HIDL_H
diff --git a/media/libaudiohal/4.0/StreamHalHidl.cpp b/media/libaudiohal/4.0/StreamHalHidl.cpp
new file mode 100644
index 0000000..0cafa36
--- /dev/null
+++ b/media/libaudiohal/4.0/StreamHalHidl.cpp
@@ -0,0 +1,752 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#define LOG_TAG "StreamHalHidl"
+//#define LOG_NDEBUG 0
+
+#include <android/hardware/audio/2.0/IStreamOutCallback.h>
+#include <hwbinder/IPCThreadState.h>
+#include <mediautils/SchedulingPolicyService.h>
+#include <utils/Log.h>
+
+#include "DeviceHalHidl.h"
+#include "EffectHalHidl.h"
+#include "StreamHalHidl.h"
+
+using ::android::hardware::audio::common::V2_0::AudioChannelMask;
+using ::android::hardware::audio::common::V2_0::AudioFormat;
+using ::android::hardware::audio::common::V2_0::ThreadInfo;
+using ::android::hardware::audio::V2_0::AudioDrain;
+using ::android::hardware::audio::V2_0::IStreamOutCallback;
+using ::android::hardware::audio::V2_0::MessageQueueFlagBits;
+using ::android::hardware::audio::V2_0::MmapBufferInfo;
+using ::android::hardware::audio::V2_0::MmapPosition;
+using ::android::hardware::audio::V2_0::ParameterValue;
+using ::android::hardware::audio::V2_0::Result;
+using ::android::hardware::audio::V2_0::TimeSpec;
+using ::android::hardware::MQDescriptorSync;
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+using ReadCommand = ::android::hardware::audio::V2_0::IStreamIn::ReadCommand;
+
+namespace android {
+
+StreamHalHidl::StreamHalHidl(IStream *stream)
+        : ConversionHelperHidl("Stream"),
+          mStream(stream),
+          mHalThreadPriority(HAL_THREAD_PRIORITY_DEFAULT),
+          mCachedBufferSize(0){
+
+    // Instrument audio signal power logging.
+    // Note: This assumes channel mask, format, and sample rate do not change after creation.
+    if (mStream != nullptr && mStreamPowerLog.isUserDebugOrEngBuild()) {
+        // Obtain audio properties (see StreamHalHidl::getAudioProperties() below).
+        Return<void> ret = mStream->getAudioProperties(
+                [&](uint32_t sr, AudioChannelMask m, AudioFormat f) {
+                mStreamPowerLog.init(sr,
+                        static_cast<audio_channel_mask_t>(m),
+                        static_cast<audio_format_t>(f));
+            });
+    }
+}
+
+StreamHalHidl::~StreamHalHidl() {
+    mStream = nullptr;
+}
+
+status_t StreamHalHidl::getSampleRate(uint32_t *rate) {
+    if (!mStream) return NO_INIT;
+    return processReturn("getSampleRate", mStream->getSampleRate(), rate);
+}
+
+status_t StreamHalHidl::getBufferSize(size_t *size) {
+    if (!mStream) return NO_INIT;
+    status_t status = processReturn("getBufferSize", mStream->getBufferSize(), size);
+    if (status == OK) {
+        mCachedBufferSize = *size;
+    }
+    return status;
+}
+
+status_t StreamHalHidl::getChannelMask(audio_channel_mask_t *mask) {
+    if (!mStream) return NO_INIT;
+    return processReturn("getChannelMask", mStream->getChannelMask(), mask);
+}
+
+status_t StreamHalHidl::getFormat(audio_format_t *format) {
+    if (!mStream) return NO_INIT;
+    return processReturn("getFormat", mStream->getFormat(), format);
+}
+
+status_t StreamHalHidl::getAudioProperties(
+        uint32_t *sampleRate, audio_channel_mask_t *mask, audio_format_t *format) {
+    if (!mStream) return NO_INIT;
+    Return<void> ret = mStream->getAudioProperties(
+            [&](uint32_t sr, AudioChannelMask m, AudioFormat f) {
+                *sampleRate = sr;
+                *mask = static_cast<audio_channel_mask_t>(m);
+                *format = static_cast<audio_format_t>(f);
+            });
+    return processReturn("getAudioProperties", ret);
+}
+
+status_t StreamHalHidl::setParameters(const String8& kvPairs) {
+    if (!mStream) return NO_INIT;
+    hidl_vec<ParameterValue> hidlParams;
+    status_t status = parametersFromHal(kvPairs, &hidlParams);
+    if (status != OK) return status;
+    return processReturn("setParameters", mStream->setParameters(hidlParams));
+}
+
+status_t StreamHalHidl::getParameters(const String8& keys, String8 *values) {
+    values->clear();
+    if (!mStream) return NO_INIT;
+    hidl_vec<hidl_string> hidlKeys;
+    status_t status = keysFromHal(keys, &hidlKeys);
+    if (status != OK) return status;
+    Result retval;
+    Return<void> ret = mStream->getParameters(
+            hidlKeys,
+            [&](Result r, const hidl_vec<ParameterValue>& parameters) {
+                retval = r;
+                if (retval == Result::OK) {
+                    parametersToHal(parameters, values);
+                }
+            });
+    return processReturn("getParameters", ret, retval);
+}
+
+status_t StreamHalHidl::addEffect(sp<EffectHalInterface> effect) {
+    if (!mStream) return NO_INIT;
+    return processReturn("addEffect", mStream->addEffect(
+                    static_cast<EffectHalHidl*>(effect.get())->effectId()));
+}
+
+status_t StreamHalHidl::removeEffect(sp<EffectHalInterface> effect) {
+    if (!mStream) return NO_INIT;
+    return processReturn("removeEffect", mStream->removeEffect(
+                    static_cast<EffectHalHidl*>(effect.get())->effectId()));
+}
+
+status_t StreamHalHidl::standby() {
+    if (!mStream) return NO_INIT;
+    return processReturn("standby", mStream->standby());
+}
+
+status_t StreamHalHidl::dump(int fd) {
+    if (!mStream) return NO_INIT;
+    native_handle_t* hidlHandle = native_handle_create(1, 0);
+    hidlHandle->data[0] = fd;
+    Return<void> ret = mStream->debugDump(hidlHandle);
+    native_handle_delete(hidlHandle);
+    mStreamPowerLog.dump(fd);
+    return processReturn("dump", ret);
+}
+
+status_t StreamHalHidl::start() {
+    if (!mStream) return NO_INIT;
+    return processReturn("start", mStream->start());
+}
+
+status_t StreamHalHidl::stop() {
+    if (!mStream) return NO_INIT;
+    return processReturn("stop", mStream->stop());
+}
+
+status_t StreamHalHidl::createMmapBuffer(int32_t minSizeFrames,
+                                  struct audio_mmap_buffer_info *info) {
+    Result retval;
+    Return<void> ret = mStream->createMmapBuffer(
+            minSizeFrames,
+            [&](Result r, const MmapBufferInfo& hidlInfo) {
+                retval = r;
+                if (retval == Result::OK) {
+                    const native_handle *handle = hidlInfo.sharedMemory.handle();
+                    if (handle->numFds > 0) {
+                        info->shared_memory_fd = handle->data[0];
+                        info->buffer_size_frames = hidlInfo.bufferSizeFrames;
+                        info->burst_size_frames = hidlInfo.burstSizeFrames;
+                        // info->shared_memory_address is not needed in HIDL context
+                        info->shared_memory_address = NULL;
+                    } else {
+                        retval = Result::NOT_INITIALIZED;
+                    }
+                }
+            });
+    return processReturn("createMmapBuffer", ret, retval);
+}
+
+status_t StreamHalHidl::getMmapPosition(struct audio_mmap_position *position) {
+    Result retval;
+    Return<void> ret = mStream->getMmapPosition(
+            [&](Result r, const MmapPosition& hidlPosition) {
+                retval = r;
+                if (retval == Result::OK) {
+                    position->time_nanoseconds = hidlPosition.timeNanoseconds;
+                    position->position_frames = hidlPosition.positionFrames;
+                }
+            });
+    return processReturn("getMmapPosition", ret, retval);
+}
+
+status_t StreamHalHidl::setHalThreadPriority(int priority) {
+    mHalThreadPriority = priority;
+    return OK;
+}
+
+status_t StreamHalHidl::getCachedBufferSize(size_t *size) {
+    if (mCachedBufferSize != 0) {
+        *size = mCachedBufferSize;
+        return OK;
+    }
+    return getBufferSize(size);
+}
+
+bool StreamHalHidl::requestHalThreadPriority(pid_t threadPid, pid_t threadId) {
+    if (mHalThreadPriority == HAL_THREAD_PRIORITY_DEFAULT) {
+        return true;
+    }
+    int err = requestPriority(
+            threadPid, threadId,
+            mHalThreadPriority, false /*isForApp*/, true /*asynchronous*/);
+    ALOGE_IF(err, "failed to set priority %d for pid %d tid %d; error %d",
+            mHalThreadPriority, threadPid, threadId, err);
+    // Audio will still work, but latency will be higher and sometimes unacceptable.
+    return err == 0;
+}
+
+namespace {
+
+/* Notes on callback ownership.
+
+This is how (Hw)Binder ownership model looks like. The server implementation
+is owned by Binder framework (via sp<>). Proxies are owned by clients.
+When the last proxy disappears, Binder framework releases the server impl.
+
+Thus, it is not needed to keep any references to StreamOutCallback (this is
+the server impl) -- it will live as long as HAL server holds a strong ref to
+IStreamOutCallback proxy. We clear that reference by calling 'clearCallback'
+from the destructor of StreamOutHalHidl.
+
+The callback only keeps a weak reference to the stream. The stream is owned
+by AudioFlinger.
+
+*/
+
+struct StreamOutCallback : public IStreamOutCallback {
+    StreamOutCallback(const wp<StreamOutHalHidl>& stream) : mStream(stream) {}
+
+    // IStreamOutCallback implementation
+    Return<void> onWriteReady()  override {
+        sp<StreamOutHalHidl> stream = mStream.promote();
+        if (stream != 0) {
+            stream->onWriteReady();
+        }
+        return Void();
+    }
+
+    Return<void> onDrainReady()  override {
+        sp<StreamOutHalHidl> stream = mStream.promote();
+        if (stream != 0) {
+            stream->onDrainReady();
+        }
+        return Void();
+    }
+
+    Return<void> onError()  override {
+        sp<StreamOutHalHidl> stream = mStream.promote();
+        if (stream != 0) {
+            stream->onError();
+        }
+        return Void();
+    }
+
+  private:
+    wp<StreamOutHalHidl> mStream;
+};
+
+}  // namespace
+
+StreamOutHalHidl::StreamOutHalHidl(const sp<IStreamOut>& stream)
+        : StreamHalHidl(stream.get()), mStream(stream), mWriterClient(0), mEfGroup(nullptr) {
+}
+
+StreamOutHalHidl::~StreamOutHalHidl() {
+    if (mStream != 0) {
+        if (mCallback.unsafe_get()) {
+            processReturn("clearCallback", mStream->clearCallback());
+        }
+        processReturn("close", mStream->close());
+        mStream.clear();
+    }
+    mCallback.clear();
+    hardware::IPCThreadState::self()->flushCommands();
+    if (mEfGroup) {
+        EventFlag::deleteEventFlag(&mEfGroup);
+    }
+}
+
+status_t StreamOutHalHidl::getFrameSize(size_t *size) {
+    if (mStream == 0) return NO_INIT;
+    return processReturn("getFrameSize", mStream->getFrameSize(), size);
+}
+
+status_t StreamOutHalHidl::getLatency(uint32_t *latency) {
+    if (mStream == 0) return NO_INIT;
+    if (mWriterClient == gettid() && mCommandMQ) {
+        return callWriterThread(
+                WriteCommand::GET_LATENCY, "getLatency", nullptr, 0,
+                [&](const WriteStatus& writeStatus) {
+                    *latency = writeStatus.reply.latencyMs;
+                });
+    } else {
+        return processReturn("getLatency", mStream->getLatency(), latency);
+    }
+}
+
+status_t StreamOutHalHidl::setVolume(float left, float right) {
+    if (mStream == 0) return NO_INIT;
+    return processReturn("setVolume", mStream->setVolume(left, right));
+}
+
+status_t StreamOutHalHidl::write(const void *buffer, size_t bytes, size_t *written) {
+    if (mStream == 0) return NO_INIT;
+    *written = 0;
+
+    if (bytes == 0 && !mDataMQ) {
+        // Can't determine the size for the MQ buffer. Wait for a non-empty write request.
+        ALOGW_IF(mCallback.unsafe_get(), "First call to async write with 0 bytes");
+        return OK;
+    }
+
+    status_t status;
+    if (!mDataMQ) {
+        // In case if playback starts close to the end of a compressed track, the bytes
+        // that need to be written is less than the actual buffer size. Need to use
+        // full buffer size for the MQ since otherwise after seeking back to the middle
+        // data will be truncated.
+        size_t bufferSize;
+        if ((status = getCachedBufferSize(&bufferSize)) != OK) {
+            return status;
+        }
+        if (bytes > bufferSize) bufferSize = bytes;
+        if ((status = prepareForWriting(bufferSize)) != OK) {
+            return status;
+        }
+    }
+
+    status = callWriterThread(
+            WriteCommand::WRITE, "write", static_cast<const uint8_t*>(buffer), bytes,
+            [&] (const WriteStatus& writeStatus) {
+                *written = writeStatus.reply.written;
+                // Diagnostics of the cause of b/35813113.
+                ALOGE_IF(*written > bytes,
+                        "hal reports more bytes written than asked for: %lld > %lld",
+                        (long long)*written, (long long)bytes);
+            });
+    mStreamPowerLog.log(buffer, *written);
+    return status;
+}
+
+status_t StreamOutHalHidl::callWriterThread(
+        WriteCommand cmd, const char* cmdName,
+        const uint8_t* data, size_t dataSize, StreamOutHalHidl::WriterCallback callback) {
+    if (!mCommandMQ->write(&cmd)) {
+        ALOGE("command message queue write failed for \"%s\"", cmdName);
+        return -EAGAIN;
+    }
+    if (data != nullptr) {
+        size_t availableToWrite = mDataMQ->availableToWrite();
+        if (dataSize > availableToWrite) {
+            ALOGW("truncating write data from %lld to %lld due to insufficient data queue space",
+                    (long long)dataSize, (long long)availableToWrite);
+            dataSize = availableToWrite;
+        }
+        if (!mDataMQ->write(data, dataSize)) {
+            ALOGE("data message queue write failed for \"%s\"", cmdName);
+        }
+    }
+    mEfGroup->wake(static_cast<uint32_t>(MessageQueueFlagBits::NOT_EMPTY));
+
+    // TODO: Remove manual event flag handling once blocking MQ is implemented. b/33815422
+    uint32_t efState = 0;
+retry:
+    status_t ret = mEfGroup->wait(static_cast<uint32_t>(MessageQueueFlagBits::NOT_FULL), &efState);
+    if (efState & static_cast<uint32_t>(MessageQueueFlagBits::NOT_FULL)) {
+        WriteStatus writeStatus;
+        writeStatus.retval = Result::NOT_INITIALIZED;
+        if (!mStatusMQ->read(&writeStatus)) {
+            ALOGE("status message read failed for \"%s\"", cmdName);
+        }
+        if (writeStatus.retval == Result::OK) {
+            ret = OK;
+            callback(writeStatus);
+        } else {
+            ret = processReturn(cmdName, writeStatus.retval);
+        }
+        return ret;
+    }
+    if (ret == -EAGAIN || ret == -EINTR) {
+        // Spurious wakeup. This normally retries no more than once.
+        goto retry;
+    }
+    return ret;
+}
+
+status_t StreamOutHalHidl::prepareForWriting(size_t bufferSize) {
+    std::unique_ptr<CommandMQ> tempCommandMQ;
+    std::unique_ptr<DataMQ> tempDataMQ;
+    std::unique_ptr<StatusMQ> tempStatusMQ;
+    Result retval;
+    pid_t halThreadPid, halThreadTid;
+    Return<void> ret = mStream->prepareForWriting(
+            1, bufferSize,
+            [&](Result r,
+                    const CommandMQ::Descriptor& commandMQ,
+                    const DataMQ::Descriptor& dataMQ,
+                    const StatusMQ::Descriptor& statusMQ,
+                    const ThreadInfo& halThreadInfo) {
+                retval = r;
+                if (retval == Result::OK) {
+                    tempCommandMQ.reset(new CommandMQ(commandMQ));
+                    tempDataMQ.reset(new DataMQ(dataMQ));
+                    tempStatusMQ.reset(new StatusMQ(statusMQ));
+                    if (tempDataMQ->isValid() && tempDataMQ->getEventFlagWord()) {
+                        EventFlag::createEventFlag(tempDataMQ->getEventFlagWord(), &mEfGroup);
+                    }
+                    halThreadPid = halThreadInfo.pid;
+                    halThreadTid = halThreadInfo.tid;
+                }
+            });
+    if (!ret.isOk() || retval != Result::OK) {
+        return processReturn("prepareForWriting", ret, retval);
+    }
+    if (!tempCommandMQ || !tempCommandMQ->isValid() ||
+            !tempDataMQ || !tempDataMQ->isValid() ||
+            !tempStatusMQ || !tempStatusMQ->isValid() ||
+            !mEfGroup) {
+        ALOGE_IF(!tempCommandMQ, "Failed to obtain command message queue for writing");
+        ALOGE_IF(tempCommandMQ && !tempCommandMQ->isValid(),
+                "Command message queue for writing is invalid");
+        ALOGE_IF(!tempDataMQ, "Failed to obtain data message queue for writing");
+        ALOGE_IF(tempDataMQ && !tempDataMQ->isValid(), "Data message queue for writing is invalid");
+        ALOGE_IF(!tempStatusMQ, "Failed to obtain status message queue for writing");
+        ALOGE_IF(tempStatusMQ && !tempStatusMQ->isValid(),
+                "Status message queue for writing is invalid");
+        ALOGE_IF(!mEfGroup, "Event flag creation for writing failed");
+        return NO_INIT;
+    }
+    requestHalThreadPriority(halThreadPid, halThreadTid);
+
+    mCommandMQ = std::move(tempCommandMQ);
+    mDataMQ = std::move(tempDataMQ);
+    mStatusMQ = std::move(tempStatusMQ);
+    mWriterClient = gettid();
+    return OK;
+}
+
+status_t StreamOutHalHidl::getRenderPosition(uint32_t *dspFrames) {
+    if (mStream == 0) return NO_INIT;
+    Result retval;
+    Return<void> ret = mStream->getRenderPosition(
+            [&](Result r, uint32_t d) {
+                retval = r;
+                if (retval == Result::OK) {
+                    *dspFrames = d;
+                }
+            });
+    return processReturn("getRenderPosition", ret, retval);
+}
+
+status_t StreamOutHalHidl::getNextWriteTimestamp(int64_t *timestamp) {
+    if (mStream == 0) return NO_INIT;
+    Result retval;
+    Return<void> ret = mStream->getNextWriteTimestamp(
+            [&](Result r, int64_t t) {
+                retval = r;
+                if (retval == Result::OK) {
+                    *timestamp = t;
+                }
+            });
+    return processReturn("getRenderPosition", ret, retval);
+}
+
+status_t StreamOutHalHidl::setCallback(wp<StreamOutHalInterfaceCallback> callback) {
+    if (mStream == 0) return NO_INIT;
+    status_t status = processReturn(
+            "setCallback", mStream->setCallback(new StreamOutCallback(this)));
+    if (status == OK) {
+        mCallback = callback;
+    }
+    return status;
+}
+
+status_t StreamOutHalHidl::supportsPauseAndResume(bool *supportsPause, bool *supportsResume) {
+    if (mStream == 0) return NO_INIT;
+    Return<void> ret = mStream->supportsPauseAndResume(
+            [&](bool p, bool r) {
+                *supportsPause = p;
+                *supportsResume = r;
+            });
+    return processReturn("supportsPauseAndResume", ret);
+}
+
+status_t StreamOutHalHidl::pause() {
+    if (mStream == 0) return NO_INIT;
+    return processReturn("pause", mStream->pause());
+}
+
+status_t StreamOutHalHidl::resume() {
+    if (mStream == 0) return NO_INIT;
+    return processReturn("pause", mStream->resume());
+}
+
+status_t StreamOutHalHidl::supportsDrain(bool *supportsDrain) {
+    if (mStream == 0) return NO_INIT;
+    return processReturn("supportsDrain", mStream->supportsDrain(), supportsDrain);
+}
+
+status_t StreamOutHalHidl::drain(bool earlyNotify) {
+    if (mStream == 0) return NO_INIT;
+    return processReturn(
+            "drain", mStream->drain(earlyNotify ? AudioDrain::EARLY_NOTIFY : AudioDrain::ALL));
+}
+
+status_t StreamOutHalHidl::flush() {
+    if (mStream == 0) return NO_INIT;
+    return processReturn("pause", mStream->flush());
+}
+
+status_t StreamOutHalHidl::getPresentationPosition(uint64_t *frames, struct timespec *timestamp) {
+    if (mStream == 0) return NO_INIT;
+    if (mWriterClient == gettid() && mCommandMQ) {
+        return callWriterThread(
+                WriteCommand::GET_PRESENTATION_POSITION, "getPresentationPosition", nullptr, 0,
+                [&](const WriteStatus& writeStatus) {
+                    *frames = writeStatus.reply.presentationPosition.frames;
+                    timestamp->tv_sec = writeStatus.reply.presentationPosition.timeStamp.tvSec;
+                    timestamp->tv_nsec = writeStatus.reply.presentationPosition.timeStamp.tvNSec;
+                });
+    } else {
+        Result retval;
+        Return<void> ret = mStream->getPresentationPosition(
+                [&](Result r, uint64_t hidlFrames, const TimeSpec& hidlTimeStamp) {
+                    retval = r;
+                    if (retval == Result::OK) {
+                        *frames = hidlFrames;
+                        timestamp->tv_sec = hidlTimeStamp.tvSec;
+                        timestamp->tv_nsec = hidlTimeStamp.tvNSec;
+                    }
+                });
+        return processReturn("getPresentationPosition", ret, retval);
+    }
+}
+
+void StreamOutHalHidl::onWriteReady() {
+    sp<StreamOutHalInterfaceCallback> callback = mCallback.promote();
+    if (callback == 0) return;
+    ALOGV("asyncCallback onWriteReady");
+    callback->onWriteReady();
+}
+
+void StreamOutHalHidl::onDrainReady() {
+    sp<StreamOutHalInterfaceCallback> callback = mCallback.promote();
+    if (callback == 0) return;
+    ALOGV("asyncCallback onDrainReady");
+    callback->onDrainReady();
+}
+
+void StreamOutHalHidl::onError() {
+    sp<StreamOutHalInterfaceCallback> callback = mCallback.promote();
+    if (callback == 0) return;
+    ALOGV("asyncCallback onError");
+    callback->onError();
+}
+
+
+StreamInHalHidl::StreamInHalHidl(const sp<IStreamIn>& stream)
+        : StreamHalHidl(stream.get()), mStream(stream), mReaderClient(0), mEfGroup(nullptr) {
+}
+
+StreamInHalHidl::~StreamInHalHidl() {
+    if (mStream != 0) {
+        processReturn("close", mStream->close());
+        mStream.clear();
+        hardware::IPCThreadState::self()->flushCommands();
+    }
+    if (mEfGroup) {
+        EventFlag::deleteEventFlag(&mEfGroup);
+    }
+}
+
+status_t StreamInHalHidl::getFrameSize(size_t *size) {
+    if (mStream == 0) return NO_INIT;
+    return processReturn("getFrameSize", mStream->getFrameSize(), size);
+}
+
+status_t StreamInHalHidl::setGain(float gain) {
+    if (mStream == 0) return NO_INIT;
+    return processReturn("setGain", mStream->setGain(gain));
+}
+
+status_t StreamInHalHidl::read(void *buffer, size_t bytes, size_t *read) {
+    if (mStream == 0) return NO_INIT;
+    *read = 0;
+
+    if (bytes == 0 && !mDataMQ) {
+        // Can't determine the size for the MQ buffer. Wait for a non-empty read request.
+        return OK;
+    }
+
+    status_t status;
+    if (!mDataMQ && (status = prepareForReading(bytes)) != OK) {
+        return status;
+    }
+
+    ReadParameters params;
+    params.command = ReadCommand::READ;
+    params.params.read = bytes;
+    status = callReaderThread(params, "read",
+            [&](const ReadStatus& readStatus) {
+                const size_t availToRead = mDataMQ->availableToRead();
+                if (!mDataMQ->read(static_cast<uint8_t*>(buffer), std::min(bytes, availToRead))) {
+                    ALOGE("data message queue read failed for \"read\"");
+                }
+                ALOGW_IF(availToRead != readStatus.reply.read,
+                        "HAL read report inconsistent: mq = %d, status = %d",
+                        (int32_t)availToRead, (int32_t)readStatus.reply.read);
+                *read = readStatus.reply.read;
+            });
+    mStreamPowerLog.log(buffer, *read);
+    return status;
+}
+
+status_t StreamInHalHidl::callReaderThread(
+        const ReadParameters& params, const char* cmdName,
+        StreamInHalHidl::ReaderCallback callback) {
+    if (!mCommandMQ->write(&params)) {
+        ALOGW("command message queue write failed");
+        return -EAGAIN;
+    }
+    mEfGroup->wake(static_cast<uint32_t>(MessageQueueFlagBits::NOT_FULL));
+
+    // TODO: Remove manual event flag handling once blocking MQ is implemented. b/33815422
+    uint32_t efState = 0;
+retry:
+    status_t ret = mEfGroup->wait(static_cast<uint32_t>(MessageQueueFlagBits::NOT_EMPTY), &efState);
+    if (efState & static_cast<uint32_t>(MessageQueueFlagBits::NOT_EMPTY)) {
+        ReadStatus readStatus;
+        readStatus.retval = Result::NOT_INITIALIZED;
+        if (!mStatusMQ->read(&readStatus)) {
+            ALOGE("status message read failed for \"%s\"", cmdName);
+        }
+         if (readStatus.retval == Result::OK) {
+            ret = OK;
+            callback(readStatus);
+        } else {
+            ret = processReturn(cmdName, readStatus.retval);
+        }
+        return ret;
+    }
+    if (ret == -EAGAIN || ret == -EINTR) {
+        // Spurious wakeup. This normally retries no more than once.
+        goto retry;
+    }
+    return ret;
+}
+
+status_t StreamInHalHidl::prepareForReading(size_t bufferSize) {
+    std::unique_ptr<CommandMQ> tempCommandMQ;
+    std::unique_ptr<DataMQ> tempDataMQ;
+    std::unique_ptr<StatusMQ> tempStatusMQ;
+    Result retval;
+    pid_t halThreadPid, halThreadTid;
+    Return<void> ret = mStream->prepareForReading(
+            1, bufferSize,
+            [&](Result r,
+                    const CommandMQ::Descriptor& commandMQ,
+                    const DataMQ::Descriptor& dataMQ,
+                    const StatusMQ::Descriptor& statusMQ,
+                    const ThreadInfo& halThreadInfo) {
+                retval = r;
+                if (retval == Result::OK) {
+                    tempCommandMQ.reset(new CommandMQ(commandMQ));
+                    tempDataMQ.reset(new DataMQ(dataMQ));
+                    tempStatusMQ.reset(new StatusMQ(statusMQ));
+                    if (tempDataMQ->isValid() && tempDataMQ->getEventFlagWord()) {
+                        EventFlag::createEventFlag(tempDataMQ->getEventFlagWord(), &mEfGroup);
+                    }
+                    halThreadPid = halThreadInfo.pid;
+                    halThreadTid = halThreadInfo.tid;
+                }
+            });
+    if (!ret.isOk() || retval != Result::OK) {
+        return processReturn("prepareForReading", ret, retval);
+    }
+    if (!tempCommandMQ || !tempCommandMQ->isValid() ||
+            !tempDataMQ || !tempDataMQ->isValid() ||
+            !tempStatusMQ || !tempStatusMQ->isValid() ||
+            !mEfGroup) {
+        ALOGE_IF(!tempCommandMQ, "Failed to obtain command message queue for writing");
+        ALOGE_IF(tempCommandMQ && !tempCommandMQ->isValid(),
+                "Command message queue for writing is invalid");
+        ALOGE_IF(!tempDataMQ, "Failed to obtain data message queue for reading");
+        ALOGE_IF(tempDataMQ && !tempDataMQ->isValid(), "Data message queue for reading is invalid");
+        ALOGE_IF(!tempStatusMQ, "Failed to obtain status message queue for reading");
+        ALOGE_IF(tempStatusMQ && !tempStatusMQ->isValid(),
+                "Status message queue for reading is invalid");
+        ALOGE_IF(!mEfGroup, "Event flag creation for reading failed");
+        return NO_INIT;
+    }
+    requestHalThreadPriority(halThreadPid, halThreadTid);
+
+    mCommandMQ = std::move(tempCommandMQ);
+    mDataMQ = std::move(tempDataMQ);
+    mStatusMQ = std::move(tempStatusMQ);
+    mReaderClient = gettid();
+    return OK;
+}
+
+status_t StreamInHalHidl::getInputFramesLost(uint32_t *framesLost) {
+    if (mStream == 0) return NO_INIT;
+    return processReturn("getInputFramesLost", mStream->getInputFramesLost(), framesLost);
+}
+
+status_t StreamInHalHidl::getCapturePosition(int64_t *frames, int64_t *time) {
+    if (mStream == 0) return NO_INIT;
+    if (mReaderClient == gettid() && mCommandMQ) {
+        ReadParameters params;
+        params.command = ReadCommand::GET_CAPTURE_POSITION;
+        return callReaderThread(params, "getCapturePosition",
+                [&](const ReadStatus& readStatus) {
+                    *frames = readStatus.reply.capturePosition.frames;
+                    *time = readStatus.reply.capturePosition.time;
+                });
+    } else {
+        Result retval;
+        Return<void> ret = mStream->getCapturePosition(
+                [&](Result r, uint64_t hidlFrames, uint64_t hidlTime) {
+                    retval = r;
+                    if (retval == Result::OK) {
+                        *frames = hidlFrames;
+                        *time = hidlTime;
+                    }
+                });
+        return processReturn("getCapturePosition", ret, retval);
+    }
+}
+
+} // namespace android
diff --git a/media/libaudiohal/4.0/StreamHalHidl.h b/media/libaudiohal/4.0/StreamHalHidl.h
new file mode 100644
index 0000000..d4ab943
--- /dev/null
+++ b/media/libaudiohal/4.0/StreamHalHidl.h
@@ -0,0 +1,239 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#ifndef ANDROID_HARDWARE_STREAM_HAL_HIDL_H
+#define ANDROID_HARDWARE_STREAM_HAL_HIDL_H
+
+#include <atomic>
+
+#include <android/hardware/audio/2.0/IStream.h>
+#include <android/hardware/audio/2.0/IStreamIn.h>
+#include <android/hardware/audio/2.0/IStreamOut.h>
+#include <fmq/EventFlag.h>
+#include <fmq/MessageQueue.h>
+#include <media/audiohal/StreamHalInterface.h>
+
+#include "ConversionHelperHidl.h"
+#include "StreamPowerLog.h"
+
+using ::android::hardware::audio::V2_0::IStream;
+using ::android::hardware::audio::V2_0::IStreamIn;
+using ::android::hardware::audio::V2_0::IStreamOut;
+using ::android::hardware::EventFlag;
+using ::android::hardware::MessageQueue;
+using ::android::hardware::Return;
+using ReadParameters = ::android::hardware::audio::V2_0::IStreamIn::ReadParameters;
+using ReadStatus = ::android::hardware::audio::V2_0::IStreamIn::ReadStatus;
+using WriteCommand = ::android::hardware::audio::V2_0::IStreamOut::WriteCommand;
+using WriteStatus = ::android::hardware::audio::V2_0::IStreamOut::WriteStatus;
+
+namespace android {
+
+class DeviceHalHidl;
+
+class StreamHalHidl : public virtual StreamHalInterface, public ConversionHelperHidl
+{
+  public:
+    // Return the sampling rate in Hz - eg. 44100.
+    virtual status_t getSampleRate(uint32_t *rate);
+
+    // Return size of input/output buffer in bytes for this stream - eg. 4800.
+    virtual status_t getBufferSize(size_t *size);
+
+    // Return the channel mask.
+    virtual status_t getChannelMask(audio_channel_mask_t *mask);
+
+    // Return the audio format - e.g. AUDIO_FORMAT_PCM_16_BIT.
+    virtual status_t getFormat(audio_format_t *format);
+
+    // Convenience method.
+    virtual status_t getAudioProperties(
+            uint32_t *sampleRate, audio_channel_mask_t *mask, audio_format_t *format);
+
+    // Set audio stream parameters.
+    virtual status_t setParameters(const String8& kvPairs);
+
+    // Get audio stream parameters.
+    virtual status_t getParameters(const String8& keys, String8 *values);
+
+    // Add or remove the effect on the stream.
+    virtual status_t addEffect(sp<EffectHalInterface> effect);
+    virtual status_t removeEffect(sp<EffectHalInterface> effect);
+
+    // Put the audio hardware input/output into standby mode.
+    virtual status_t standby();
+
+    virtual status_t dump(int fd);
+
+    // Start a stream operating in mmap mode.
+    virtual status_t start();
+
+    // Stop a stream operating in mmap mode.
+    virtual status_t stop();
+
+    // Retrieve information on the data buffer in mmap mode.
+    virtual status_t createMmapBuffer(int32_t minSizeFrames,
+                                      struct audio_mmap_buffer_info *info);
+
+    // Get current read/write position in the mmap buffer
+    virtual status_t getMmapPosition(struct audio_mmap_position *position);
+
+    // Set the priority of the thread that interacts with the HAL
+    // (must match the priority of the audioflinger's thread that calls 'read' / 'write')
+    virtual status_t setHalThreadPriority(int priority);
+
+  protected:
+    // Subclasses can not be constructed directly by clients.
+    explicit StreamHalHidl(IStream *stream);
+
+    // The destructor automatically closes the stream.
+    virtual ~StreamHalHidl();
+
+    status_t getCachedBufferSize(size_t *size);
+
+    bool requestHalThreadPriority(pid_t threadPid, pid_t threadId);
+
+    // mStreamPowerLog is used for audio signal power logging.
+    StreamPowerLog mStreamPowerLog;
+
+  private:
+    const int HAL_THREAD_PRIORITY_DEFAULT = -1;
+    IStream *mStream;
+    int mHalThreadPriority;
+    size_t mCachedBufferSize;
+};
+
+class StreamOutHalHidl : public StreamOutHalInterface, public StreamHalHidl {
+  public:
+    // Return the frame size (number of bytes per sample) of a stream.
+    virtual status_t getFrameSize(size_t *size);
+
+    // Return the audio hardware driver estimated latency in milliseconds.
+    virtual status_t getLatency(uint32_t *latency);
+
+    // Use this method in situations where audio mixing is done in the hardware.
+    virtual status_t setVolume(float left, float right);
+
+    // Write audio buffer to driver.
+    virtual status_t write(const void *buffer, size_t bytes, size_t *written);
+
+    // Return the number of audio frames written by the audio dsp to DAC since
+    // the output has exited standby.
+    virtual status_t getRenderPosition(uint32_t *dspFrames);
+
+    // Get the local time at which the next write to the audio driver will be presented.
+    virtual status_t getNextWriteTimestamp(int64_t *timestamp);
+
+    // Set the callback for notifying completion of non-blocking write and drain.
+    virtual status_t setCallback(wp<StreamOutHalInterfaceCallback> callback);
+
+    // Returns whether pause and resume operations are supported.
+    virtual status_t supportsPauseAndResume(bool *supportsPause, bool *supportsResume);
+
+    // Notifies to the audio driver to resume playback following a pause.
+    virtual status_t pause();
+
+    // Notifies to the audio driver to resume playback following a pause.
+    virtual status_t resume();
+
+    // Returns whether drain operation is supported.
+    virtual status_t supportsDrain(bool *supportsDrain);
+
+    // Requests notification when data buffered by the driver/hardware has been played.
+    virtual status_t drain(bool earlyNotify);
+
+    // Notifies to the audio driver to flush the queued data.
+    virtual status_t flush();
+
+    // Return a recent count of the number of audio frames presented to an external observer.
+    virtual status_t getPresentationPosition(uint64_t *frames, struct timespec *timestamp);
+
+    // Methods used by StreamOutCallback (HIDL).
+    void onWriteReady();
+    void onDrainReady();
+    void onError();
+
+  private:
+    friend class DeviceHalHidl;
+    typedef MessageQueue<WriteCommand, hardware::kSynchronizedReadWrite> CommandMQ;
+    typedef MessageQueue<uint8_t, hardware::kSynchronizedReadWrite> DataMQ;
+    typedef MessageQueue<WriteStatus, hardware::kSynchronizedReadWrite> StatusMQ;
+
+    wp<StreamOutHalInterfaceCallback> mCallback;
+    sp<IStreamOut> mStream;
+    std::unique_ptr<CommandMQ> mCommandMQ;
+    std::unique_ptr<DataMQ> mDataMQ;
+    std::unique_ptr<StatusMQ> mStatusMQ;
+    std::atomic<pid_t> mWriterClient;
+    EventFlag* mEfGroup;
+
+    // Can not be constructed directly by clients.
+    StreamOutHalHidl(const sp<IStreamOut>& stream);
+
+    virtual ~StreamOutHalHidl();
+
+    using WriterCallback = std::function<void(const WriteStatus& writeStatus)>;
+    status_t callWriterThread(
+            WriteCommand cmd, const char* cmdName,
+            const uint8_t* data, size_t dataSize, WriterCallback callback);
+    status_t prepareForWriting(size_t bufferSize);
+};
+
+class StreamInHalHidl : public StreamInHalInterface, public StreamHalHidl {
+  public:
+    // Return the frame size (number of bytes per sample) of a stream.
+    virtual status_t getFrameSize(size_t *size);
+
+    // Set the input gain for the audio driver.
+    virtual status_t setGain(float gain);
+
+    // Read audio buffer in from driver.
+    virtual status_t read(void *buffer, size_t bytes, size_t *read);
+
+    // Return the amount of input frames lost in the audio driver.
+    virtual status_t getInputFramesLost(uint32_t *framesLost);
+
+    // Return a recent count of the number of audio frames received and
+    // the clock time associated with that frame count.
+    virtual status_t getCapturePosition(int64_t *frames, int64_t *time);
+
+  private:
+    friend class DeviceHalHidl;
+    typedef MessageQueue<ReadParameters, hardware::kSynchronizedReadWrite> CommandMQ;
+    typedef MessageQueue<uint8_t, hardware::kSynchronizedReadWrite> DataMQ;
+    typedef MessageQueue<ReadStatus, hardware::kSynchronizedReadWrite> StatusMQ;
+
+    sp<IStreamIn> mStream;
+    std::unique_ptr<CommandMQ> mCommandMQ;
+    std::unique_ptr<DataMQ> mDataMQ;
+    std::unique_ptr<StatusMQ> mStatusMQ;
+    std::atomic<pid_t> mReaderClient;
+    EventFlag* mEfGroup;
+
+    // Can not be constructed directly by clients.
+    StreamInHalHidl(const sp<IStreamIn>& stream);
+
+    virtual ~StreamInHalHidl();
+
+    using ReaderCallback = std::function<void(const ReadStatus& readStatus)>;
+    status_t callReaderThread(
+            const ReadParameters& params, const char* cmdName, ReaderCallback callback);
+    status_t prepareForReading(size_t bufferSize);
+};
+
+} // namespace android
+
+#endif // ANDROID_HARDWARE_STREAM_HAL_HIDL_H
diff --git a/media/libaudiohal/4.0/StreamHalLocal.cpp b/media/libaudiohal/4.0/StreamHalLocal.cpp
new file mode 100644
index 0000000..8d61e24
--- /dev/null
+++ b/media/libaudiohal/4.0/StreamHalLocal.cpp
@@ -0,0 +1,316 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#define LOG_TAG "StreamHalLocal"
+//#define LOG_NDEBUG 0
+
+#include <hardware/audio.h>
+#include <utils/Log.h>
+
+#include "DeviceHalLocal.h"
+#include "StreamHalLocal.h"
+
+namespace android {
+
+StreamHalLocal::StreamHalLocal(audio_stream_t *stream, sp<DeviceHalLocal> device)
+        : mDevice(device),
+          mStream(stream) {
+    // Instrument audio signal power logging.
+    // Note: This assumes channel mask, format, and sample rate do not change after creation.
+    if (mStream != nullptr && mStreamPowerLog.isUserDebugOrEngBuild()) {
+        mStreamPowerLog.init(mStream->get_sample_rate(mStream),
+                mStream->get_channels(mStream),
+                mStream->get_format(mStream));
+    }
+}
+
+StreamHalLocal::~StreamHalLocal() {
+    mStream = 0;
+    mDevice.clear();
+}
+
+status_t StreamHalLocal::getSampleRate(uint32_t *rate) {
+    *rate = mStream->get_sample_rate(mStream);
+    return OK;
+}
+
+status_t StreamHalLocal::getBufferSize(size_t *size) {
+    *size = mStream->get_buffer_size(mStream);
+    return OK;
+}
+
+status_t StreamHalLocal::getChannelMask(audio_channel_mask_t *mask) {
+    *mask = mStream->get_channels(mStream);
+    return OK;
+}
+
+status_t StreamHalLocal::getFormat(audio_format_t *format) {
+    *format = mStream->get_format(mStream);
+    return OK;
+}
+
+status_t StreamHalLocal::getAudioProperties(
+        uint32_t *sampleRate, audio_channel_mask_t *mask, audio_format_t *format) {
+    *sampleRate = mStream->get_sample_rate(mStream);
+    *mask = mStream->get_channels(mStream);
+    *format = mStream->get_format(mStream);
+    return OK;
+}
+
+status_t StreamHalLocal::setParameters(const String8& kvPairs) {
+    return mStream->set_parameters(mStream, kvPairs.string());
+}
+
+status_t StreamHalLocal::getParameters(const String8& keys, String8 *values) {
+    char *halValues = mStream->get_parameters(mStream, keys.string());
+    if (halValues != NULL) {
+        values->setTo(halValues);
+        free(halValues);
+    } else {
+        values->clear();
+    }
+    return OK;
+}
+
+status_t StreamHalLocal::addEffect(sp<EffectHalInterface>) {
+    LOG_ALWAYS_FATAL("Local streams can not have effects");
+    return INVALID_OPERATION;
+}
+
+status_t StreamHalLocal::removeEffect(sp<EffectHalInterface>) {
+    LOG_ALWAYS_FATAL("Local streams can not have effects");
+    return INVALID_OPERATION;
+}
+
+status_t StreamHalLocal::standby() {
+    return mStream->standby(mStream);
+}
+
+status_t StreamHalLocal::dump(int fd) {
+    status_t status = mStream->dump(mStream, fd);
+    mStreamPowerLog.dump(fd);
+    return status;
+}
+
+status_t StreamHalLocal::setHalThreadPriority(int) {
+    // Don't need to do anything as local hal is executed by audioflinger directly
+    // on the same thread.
+    return OK;
+}
+
+StreamOutHalLocal::StreamOutHalLocal(audio_stream_out_t *stream, sp<DeviceHalLocal> device)
+        : StreamHalLocal(&stream->common, device), mStream(stream) {
+}
+
+StreamOutHalLocal::~StreamOutHalLocal() {
+    mCallback.clear();
+    mDevice->closeOutputStream(mStream);
+    mStream = 0;
+}
+
+status_t StreamOutHalLocal::getFrameSize(size_t *size) {
+    *size = audio_stream_out_frame_size(mStream);
+    return OK;
+}
+
+status_t StreamOutHalLocal::getLatency(uint32_t *latency) {
+    *latency = mStream->get_latency(mStream);
+    return OK;
+}
+
+status_t StreamOutHalLocal::setVolume(float left, float right) {
+    if (mStream->set_volume == NULL) return INVALID_OPERATION;
+    return mStream->set_volume(mStream, left, right);
+}
+
+status_t StreamOutHalLocal::write(const void *buffer, size_t bytes, size_t *written) {
+    ssize_t writeResult = mStream->write(mStream, buffer, bytes);
+    if (writeResult > 0) {
+        *written = writeResult;
+        mStreamPowerLog.log(buffer, *written);
+        return OK;
+    } else {
+        *written = 0;
+        return writeResult;
+    }
+}
+
+status_t StreamOutHalLocal::getRenderPosition(uint32_t *dspFrames) {
+    return mStream->get_render_position(mStream, dspFrames);
+}
+
+status_t StreamOutHalLocal::getNextWriteTimestamp(int64_t *timestamp) {
+    if (mStream->get_next_write_timestamp == NULL) return INVALID_OPERATION;
+    return mStream->get_next_write_timestamp(mStream, timestamp);
+}
+
+status_t StreamOutHalLocal::setCallback(wp<StreamOutHalInterfaceCallback> callback) {
+    if (mStream->set_callback == NULL) return INVALID_OPERATION;
+    status_t result = mStream->set_callback(mStream, StreamOutHalLocal::asyncCallback, this);
+    if (result == OK) {
+        mCallback = callback;
+    }
+    return result;
+}
+
+// static
+int StreamOutHalLocal::asyncCallback(stream_callback_event_t event, void*, void *cookie) {
+    // We act as if we gave a wp<StreamOutHalLocal> to HAL. This way we should handle
+    // correctly the case when the callback is invoked while StreamOutHalLocal's destructor is
+    // already running, because the destructor is invoked after the refcount has been atomically
+    // decremented.
+    wp<StreamOutHalLocal> weakSelf(static_cast<StreamOutHalLocal*>(cookie));
+    sp<StreamOutHalLocal> self = weakSelf.promote();
+    if (self == 0) return 0;
+    sp<StreamOutHalInterfaceCallback> callback = self->mCallback.promote();
+    if (callback == 0) return 0;
+    ALOGV("asyncCallback() event %d", event);
+    switch (event) {
+        case STREAM_CBK_EVENT_WRITE_READY:
+            callback->onWriteReady();
+            break;
+        case STREAM_CBK_EVENT_DRAIN_READY:
+            callback->onDrainReady();
+            break;
+        case STREAM_CBK_EVENT_ERROR:
+            callback->onError();
+            break;
+        default:
+            ALOGW("asyncCallback() unknown event %d", event);
+            break;
+    }
+    return 0;
+}
+
+status_t StreamOutHalLocal::supportsPauseAndResume(bool *supportsPause, bool *supportsResume) {
+    *supportsPause = mStream->pause != NULL;
+    *supportsResume = mStream->resume != NULL;
+    return OK;
+}
+
+status_t StreamOutHalLocal::pause() {
+    if (mStream->pause == NULL) return INVALID_OPERATION;
+    return mStream->pause(mStream);
+}
+
+status_t StreamOutHalLocal::resume() {
+    if (mStream->resume == NULL) return INVALID_OPERATION;
+    return mStream->resume(mStream);
+}
+
+status_t StreamOutHalLocal::supportsDrain(bool *supportsDrain) {
+    *supportsDrain = mStream->drain != NULL;
+    return OK;
+}
+
+status_t StreamOutHalLocal::drain(bool earlyNotify) {
+    if (mStream->drain == NULL) return INVALID_OPERATION;
+    return mStream->drain(mStream, earlyNotify ? AUDIO_DRAIN_EARLY_NOTIFY : AUDIO_DRAIN_ALL);
+}
+
+status_t StreamOutHalLocal::flush() {
+    if (mStream->flush == NULL) return INVALID_OPERATION;
+    return mStream->flush(mStream);
+}
+
+status_t StreamOutHalLocal::getPresentationPosition(uint64_t *frames, struct timespec *timestamp) {
+    if (mStream->get_presentation_position == NULL) return INVALID_OPERATION;
+    return mStream->get_presentation_position(mStream, frames, timestamp);
+}
+
+status_t StreamOutHalLocal::start() {
+    if (mStream->start == NULL) return INVALID_OPERATION;
+    return mStream->start(mStream);
+}
+
+status_t StreamOutHalLocal::stop() {
+    if (mStream->stop == NULL) return INVALID_OPERATION;
+    return mStream->stop(mStream);
+}
+
+status_t StreamOutHalLocal::createMmapBuffer(int32_t minSizeFrames,
+                                  struct audio_mmap_buffer_info *info) {
+    if (mStream->create_mmap_buffer == NULL) return INVALID_OPERATION;
+    return mStream->create_mmap_buffer(mStream, minSizeFrames, info);
+}
+
+status_t StreamOutHalLocal::getMmapPosition(struct audio_mmap_position *position) {
+    if (mStream->get_mmap_position == NULL) return INVALID_OPERATION;
+    return mStream->get_mmap_position(mStream, position);
+}
+
+StreamInHalLocal::StreamInHalLocal(audio_stream_in_t *stream, sp<DeviceHalLocal> device)
+        : StreamHalLocal(&stream->common, device), mStream(stream) {
+}
+
+StreamInHalLocal::~StreamInHalLocal() {
+    mDevice->closeInputStream(mStream);
+    mStream = 0;
+}
+
+status_t StreamInHalLocal::getFrameSize(size_t *size) {
+    *size = audio_stream_in_frame_size(mStream);
+    return OK;
+}
+
+status_t StreamInHalLocal::setGain(float gain) {
+    return mStream->set_gain(mStream, gain);
+}
+
+status_t StreamInHalLocal::read(void *buffer, size_t bytes, size_t *read) {
+    ssize_t readResult = mStream->read(mStream, buffer, bytes);
+    if (readResult > 0) {
+        *read = readResult;
+        mStreamPowerLog.log( buffer, *read);
+        return OK;
+    } else {
+        *read = 0;
+        return readResult;
+    }
+}
+
+status_t StreamInHalLocal::getInputFramesLost(uint32_t *framesLost) {
+    *framesLost = mStream->get_input_frames_lost(mStream);
+    return OK;
+}
+
+status_t StreamInHalLocal::getCapturePosition(int64_t *frames, int64_t *time) {
+    if (mStream->get_capture_position == NULL) return INVALID_OPERATION;
+    return mStream->get_capture_position(mStream, frames, time);
+}
+
+status_t StreamInHalLocal::start() {
+    if (mStream->start == NULL) return INVALID_OPERATION;
+    return mStream->start(mStream);
+}
+
+status_t StreamInHalLocal::stop() {
+    if (mStream->stop == NULL) return INVALID_OPERATION;
+    return mStream->stop(mStream);
+}
+
+status_t StreamInHalLocal::createMmapBuffer(int32_t minSizeFrames,
+                                  struct audio_mmap_buffer_info *info) {
+    if (mStream->create_mmap_buffer == NULL) return INVALID_OPERATION;
+    return mStream->create_mmap_buffer(mStream, minSizeFrames, info);
+}
+
+status_t StreamInHalLocal::getMmapPosition(struct audio_mmap_position *position) {
+    if (mStream->get_mmap_position == NULL) return INVALID_OPERATION;
+    return mStream->get_mmap_position(mStream, position);
+}
+
+} // namespace android
diff --git a/media/libaudiohal/4.0/StreamHalLocal.h b/media/libaudiohal/4.0/StreamHalLocal.h
new file mode 100644
index 0000000..c7136df
--- /dev/null
+++ b/media/libaudiohal/4.0/StreamHalLocal.h
@@ -0,0 +1,210 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#ifndef ANDROID_HARDWARE_STREAM_HAL_LOCAL_H
+#define ANDROID_HARDWARE_STREAM_HAL_LOCAL_H
+
+#include <media/audiohal/StreamHalInterface.h>
+#include "StreamPowerLog.h"
+
+namespace android {
+
+class DeviceHalLocal;
+
+class StreamHalLocal : public virtual StreamHalInterface
+{
+  public:
+    // Return the sampling rate in Hz - eg. 44100.
+    virtual status_t getSampleRate(uint32_t *rate);
+
+    // Return size of input/output buffer in bytes for this stream - eg. 4800.
+    virtual status_t getBufferSize(size_t *size);
+
+    // Return the channel mask.
+    virtual status_t getChannelMask(audio_channel_mask_t *mask);
+
+    // Return the audio format - e.g. AUDIO_FORMAT_PCM_16_BIT.
+    virtual status_t getFormat(audio_format_t *format);
+
+    // Convenience method.
+    virtual status_t getAudioProperties(
+            uint32_t *sampleRate, audio_channel_mask_t *mask, audio_format_t *format);
+
+    // Set audio stream parameters.
+    virtual status_t setParameters(const String8& kvPairs);
+
+    // Get audio stream parameters.
+    virtual status_t getParameters(const String8& keys, String8 *values);
+
+    // Add or remove the effect on the stream.
+    virtual status_t addEffect(sp<EffectHalInterface> effect);
+    virtual status_t removeEffect(sp<EffectHalInterface> effect);
+
+    // Put the audio hardware input/output into standby mode.
+    virtual status_t standby();
+
+    virtual status_t dump(int fd);
+
+    // Start a stream operating in mmap mode.
+    virtual status_t start() = 0;
+
+    // Stop a stream operating in mmap mode.
+    virtual status_t stop() = 0;
+
+    // Retrieve information on the data buffer in mmap mode.
+    virtual status_t createMmapBuffer(int32_t minSizeFrames,
+                                      struct audio_mmap_buffer_info *info) = 0;
+
+    // Get current read/write position in the mmap buffer
+    virtual status_t getMmapPosition(struct audio_mmap_position *position) = 0;
+
+    // Set the priority of the thread that interacts with the HAL
+    // (must match the priority of the audioflinger's thread that calls 'read' / 'write')
+    virtual status_t setHalThreadPriority(int priority);
+
+  protected:
+    // Subclasses can not be constructed directly by clients.
+    StreamHalLocal(audio_stream_t *stream, sp<DeviceHalLocal> device);
+
+    // The destructor automatically closes the stream.
+    virtual ~StreamHalLocal();
+
+    sp<DeviceHalLocal> mDevice;
+
+    // mStreamPowerLog is used for audio signal power logging.
+    StreamPowerLog mStreamPowerLog;
+
+  private:
+    audio_stream_t *mStream;
+};
+
+class StreamOutHalLocal : public StreamOutHalInterface, public StreamHalLocal {
+  public:
+    // Return the frame size (number of bytes per sample) of a stream.
+    virtual status_t getFrameSize(size_t *size);
+
+    // Return the audio hardware driver estimated latency in milliseconds.
+    virtual status_t getLatency(uint32_t *latency);
+
+    // Use this method in situations where audio mixing is done in the hardware.
+    virtual status_t setVolume(float left, float right);
+
+    // Write audio buffer to driver.
+    virtual status_t write(const void *buffer, size_t bytes, size_t *written);
+
+    // Return the number of audio frames written by the audio dsp to DAC since
+    // the output has exited standby.
+    virtual status_t getRenderPosition(uint32_t *dspFrames);
+
+    // Get the local time at which the next write to the audio driver will be presented.
+    virtual status_t getNextWriteTimestamp(int64_t *timestamp);
+
+    // Set the callback for notifying completion of non-blocking write and drain.
+    virtual status_t setCallback(wp<StreamOutHalInterfaceCallback> callback);
+
+    // Returns whether pause and resume operations are supported.
+    virtual status_t supportsPauseAndResume(bool *supportsPause, bool *supportsResume);
+
+    // Notifies to the audio driver to resume playback following a pause.
+    virtual status_t pause();
+
+    // Notifies to the audio driver to resume playback following a pause.
+    virtual status_t resume();
+
+    // Returns whether drain operation is supported.
+    virtual status_t supportsDrain(bool *supportsDrain);
+
+    // Requests notification when data buffered by the driver/hardware has been played.
+    virtual status_t drain(bool earlyNotify);
+
+    // Notifies to the audio driver to flush the queued data.
+    virtual status_t flush();
+
+    // Return a recent count of the number of audio frames presented to an external observer.
+    virtual status_t getPresentationPosition(uint64_t *frames, struct timespec *timestamp);
+
+    // Start a stream operating in mmap mode.
+    virtual status_t start();
+
+    // Stop a stream operating in mmap mode.
+    virtual status_t stop();
+
+    // Retrieve information on the data buffer in mmap mode.
+    virtual status_t createMmapBuffer(int32_t minSizeFrames,
+                                      struct audio_mmap_buffer_info *info);
+
+    // Get current read/write position in the mmap buffer
+    virtual status_t getMmapPosition(struct audio_mmap_position *position);
+
+  private:
+    audio_stream_out_t *mStream;
+    wp<StreamOutHalInterfaceCallback> mCallback;
+
+    friend class DeviceHalLocal;
+
+    // Can not be constructed directly by clients.
+    StreamOutHalLocal(audio_stream_out_t *stream, sp<DeviceHalLocal> device);
+
+    virtual ~StreamOutHalLocal();
+
+    static int asyncCallback(stream_callback_event_t event, void *param, void *cookie);
+};
+
+class StreamInHalLocal : public StreamInHalInterface, public StreamHalLocal {
+  public:
+    // Return the frame size (number of bytes per sample) of a stream.
+    virtual status_t getFrameSize(size_t *size);
+
+    // Set the input gain for the audio driver.
+    virtual status_t setGain(float gain);
+
+    // Read audio buffer in from driver.
+    virtual status_t read(void *buffer, size_t bytes, size_t *read);
+
+    // Return the amount of input frames lost in the audio driver.
+    virtual status_t getInputFramesLost(uint32_t *framesLost);
+
+    // Return a recent count of the number of audio frames received and
+    // the clock time associated with that frame count.
+    virtual status_t getCapturePosition(int64_t *frames, int64_t *time);
+
+    // Start a stream operating in mmap mode.
+    virtual status_t start();
+
+    // Stop a stream operating in mmap mode.
+    virtual status_t stop();
+
+    // Retrieve information on the data buffer in mmap mode.
+    virtual status_t createMmapBuffer(int32_t minSizeFrames,
+                                      struct audio_mmap_buffer_info *info);
+
+    // Get current read/write position in the mmap buffer
+    virtual status_t getMmapPosition(struct audio_mmap_position *position);
+
+  private:
+    audio_stream_in_t *mStream;
+
+    friend class DeviceHalLocal;
+
+    // Can not be constructed directly by clients.
+    StreamInHalLocal(audio_stream_in_t *stream, sp<DeviceHalLocal> device);
+
+    virtual ~StreamInHalLocal();
+};
+
+} // namespace android
+
+#endif // ANDROID_HARDWARE_STREAM_HAL_LOCAL_H
diff --git a/media/libaudiohal/4.0/StreamPowerLog.h b/media/libaudiohal/4.0/StreamPowerLog.h
new file mode 100644
index 0000000..a78b1aa
--- /dev/null
+++ b/media/libaudiohal/4.0/StreamPowerLog.h
@@ -0,0 +1,102 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+#ifndef ANDROID_HARDWARE_STREAM_POWER_LOG_H
+#define ANDROID_HARDWARE_STREAM_POWER_LOG_H
+
+#include <audio_utils/clock.h>
+#include <audio_utils/PowerLog.h>
+#include <cutils/properties.h>
+#include <system/audio.h>
+
+namespace android {
+
+class StreamPowerLog {
+public:
+    StreamPowerLog() :
+        mIsUserDebugOrEngBuild(is_userdebug_or_eng_build()),
+        mPowerLog(nullptr),
+        mFrameSize(0) {
+        // use init() to set up the power log.
+    }
+
+    ~StreamPowerLog() {
+        power_log_destroy(mPowerLog); // OK for null mPowerLog
+        mPowerLog = nullptr;
+    }
+
+    // A one-time initialization (do not call twice) before using StreamPowerLog.
+    void init(uint32_t sampleRate, audio_channel_mask_t channelMask, audio_format_t format) {
+        if (mPowerLog == nullptr) {
+            // Note: A way to get channel count for both input and output channel masks
+            // but does not check validity of the channel mask.
+            const uint32_t channelCount = popcount(audio_channel_mask_get_bits(channelMask));
+            mFrameSize = channelCount * audio_bytes_per_sample(format);
+            if (mFrameSize > 0) {
+                const size_t kPowerLogFramesPerEntry =
+                        (long long)sampleRate * kPowerLogSamplingIntervalMs / 1000;
+                mPowerLog = power_log_create(
+                        sampleRate,
+                        channelCount,
+                        format,
+                        kPowerLogEntries,
+                        kPowerLogFramesPerEntry);
+            }
+        }
+        // mPowerLog may be NULL (not the right build, format not accepted, etc.).
+    }
+
+    // Dump the power log to fd.
+    void dump(int fd) const {
+        // OK for null mPowerLog
+        (void)power_log_dump(
+                mPowerLog, fd, "      " /* prefix */, kPowerLogLines, 0 /* limit_ns */);
+    }
+
+    // Log the audio data contained in buffer.
+    void log(const void *buffer, size_t sizeInBytes) const {
+        if (mPowerLog != nullptr) { // mFrameSize is always nonzero if mPowerLog exists.
+            power_log_log(
+                    mPowerLog, buffer, sizeInBytes / mFrameSize, audio_utils_get_real_time_ns());
+        }
+    }
+
+    bool isUserDebugOrEngBuild() const {
+        return mIsUserDebugOrEngBuild;
+    }
+
+private:
+
+    static inline bool is_userdebug_or_eng_build() {
+        char value[PROPERTY_VALUE_MAX];
+        (void)property_get("ro.build.type", value, "unknown"); // ignore actual length
+        return strcmp(value, "userdebug") == 0 || strcmp(value, "eng") == 0;
+    }
+
+    // Audio signal power log configuration.
+    static const size_t kPowerLogLines = 40;
+    static const size_t kPowerLogSamplingIntervalMs = 50;
+    static const size_t kPowerLogEntries = (1 /* minutes */ * 60 /* seconds */ * 1000 /* msec */
+            / kPowerLogSamplingIntervalMs);
+
+    const bool mIsUserDebugOrEngBuild;
+    power_log_t *mPowerLog;
+    size_t mFrameSize;
+};
+
+} // namespace android
+
+#endif // ANDROID_HARDWARE_STREAM_POWER_LOG_H