Camera: add external camera@3.5

External camera@3.5 supports the new buffer management
API that allows HAL to request buffer when needed to
optimize the memory usage.

Test: smoke test TestingCamera
Bug: 109829698
Change-Id: Icfbb75a26d8e92e4eb82a680e94e183041a5174d
diff --git a/camera/device/3.5/default/Android.bp b/camera/device/3.5/default/Android.bp
index 09cf3a4..7a48865 100644
--- a/camera/device/3.5/default/Android.bp
+++ b/camera/device/3.5/default/Android.bp
@@ -20,6 +20,12 @@
     export_include_dirs: ["include/device_v3_5_impl"]
 }
 
+cc_library_headers {
+    name: "camera.device@3.5-external-impl_headers",
+    vendor: true,
+    export_include_dirs: ["include/ext_device_v3_5_impl"]
+}
+
 cc_library_shared {
     name: "camera.device@3.5-impl",
     defaults: ["hidl_defaults"],
@@ -52,3 +58,45 @@
     ],
     local_include_dirs: ["include/device_v3_5_impl"],
 }
+
+cc_library_shared {
+    name: "camera.device@3.5-external-impl",
+    defaults: ["hidl_defaults"],
+    proprietary: true,
+    vendor: true,
+    srcs: [
+        "ExternalCameraDevice.cpp",
+        "ExternalCameraDeviceSession.cpp",
+    ],
+    shared_libs: [
+        "libhidlbase",
+        "libhidltransport",
+        "libutils",
+        "libcutils",
+        "camera.device@3.2-impl",
+        "camera.device@3.3-impl",
+        "camera.device@3.4-external-impl",
+        "android.hardware.camera.device@3.2",
+        "android.hardware.camera.device@3.3",
+        "android.hardware.camera.device@3.4",
+        "android.hardware.camera.device@3.5",
+        "android.hardware.camera.provider@2.4",
+        "android.hardware.graphics.mapper@2.0",
+        "liblog",
+        "libhardware",
+        "libcamera_metadata",
+        "libfmq",
+        "libsync",
+        "libyuv",
+        "libjpeg",
+        "libexif",
+        "libtinyxml2"
+    ],
+    static_libs: [
+        "android.hardware.camera.common@1.0-helper",
+    ],
+    local_include_dirs: ["include/ext_device_v3_5_impl"],
+    export_shared_lib_headers: [
+        "libfmq",
+    ],
+}
diff --git a/camera/device/3.5/default/ExternalCameraDevice.cpp b/camera/device/3.5/default/ExternalCameraDevice.cpp
new file mode 100644
index 0000000..e8d14b5
--- /dev/null
+++ b/camera/device/3.5/default/ExternalCameraDevice.cpp
@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2018 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 "ExtCamDev@3.5"
+//#define LOG_NDEBUG 0
+#include <log/log.h>
+
+#include "ExternalCameraDevice_3_5.h"
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace device {
+namespace V3_5 {
+namespace implementation {
+
+ExternalCameraDevice::ExternalCameraDevice(
+        const std::string& cameraId, const ExternalCameraConfig& cfg) :
+        V3_4::implementation::ExternalCameraDevice(cameraId, cfg) {}
+
+ExternalCameraDevice::~ExternalCameraDevice() {}
+
+Return<void> ExternalCameraDevice::getPhysicalCameraCharacteristics(const hidl_string&,
+        V3_5::ICameraDevice::getPhysicalCameraCharacteristics_cb _hidl_cb) {
+    CameraMetadata cameraCharacteristics;
+    // External camera HAL doesn't support physical camera functions
+    _hidl_cb(Status::ILLEGAL_ARGUMENT, cameraCharacteristics);
+    return Void();
+}
+
+sp<V3_4::implementation::ExternalCameraDeviceSession> ExternalCameraDevice::createSession(
+        const sp<V3_2::ICameraDeviceCallback>& cb,
+        const ExternalCameraConfig& cfg,
+        const std::vector<SupportedV4L2Format>& sortedFormats,
+        const CroppingType& croppingType,
+        const common::V1_0::helper::CameraMetadata& chars,
+        const std::string& cameraId,
+        unique_fd v4l2Fd) {
+    return new ExternalCameraDeviceSession(
+            cb, cfg, sortedFormats, croppingType, chars, cameraId, std::move(v4l2Fd));
+}
+
+#define UPDATE(tag, data, size)                    \
+do {                                               \
+  if (metadata->update((tag), (data), (size))) {   \
+    ALOGE("Update " #tag " failed!");              \
+    return -EINVAL;                                \
+  }                                                \
+} while (0)
+
+status_t ExternalCameraDevice::initDefaultCharsKeys(
+        ::android::hardware::camera::common::V1_0::helper::CameraMetadata* metadata) {
+    status_t res =
+            V3_4::implementation::ExternalCameraDevice::initDefaultCharsKeys(metadata);
+
+    if (res != OK) {
+        return res;
+    }
+
+    const uint8_t bufMgrVer = ANDROID_INFO_SUPPORTED_BUFFER_MANAGEMENT_VERSION_HIDL_DEVICE_3_5;
+    UPDATE(ANDROID_INFO_SUPPORTED_BUFFER_MANAGEMENT_VERSION, &bufMgrVer, 1);
+
+    std::vector<int> availableCharacteristicsKeys = AVAILABLE_CHARACTERISTICS_KEYS_3_4;
+    availableCharacteristicsKeys.reserve(availableCharacteristicsKeys.size() +
+            EXTRA_CHARACTERISTICS_KEYS_3_5.size());
+    for (const auto& key : EXTRA_CHARACTERISTICS_KEYS_3_5) {
+        availableCharacteristicsKeys.push_back(key);
+    }
+    UPDATE(ANDROID_REQUEST_AVAILABLE_CHARACTERISTICS_KEYS,
+           availableCharacteristicsKeys.data(),
+           availableCharacteristicsKeys.size());
+
+    return OK;
+}
+
+#undef UPDATE
+
+}  // namespace implementation
+}  // namespace V3_5
+}  // namespace device
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
+
diff --git a/camera/device/3.5/default/ExternalCameraDeviceSession.cpp b/camera/device/3.5/default/ExternalCameraDeviceSession.cpp
new file mode 100644
index 0000000..ae7c45e
--- /dev/null
+++ b/camera/device/3.5/default/ExternalCameraDeviceSession.cpp
@@ -0,0 +1,303 @@
+/*
+ * Copyright (C) 2018 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 "ExtCamDevSsn@3.5"
+#include <android/log.h>
+
+#include <utils/Trace.h>
+#include "ExternalCameraDeviceSession.h"
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace device {
+namespace V3_5 {
+namespace implementation {
+
+ExternalCameraDeviceSession::ExternalCameraDeviceSession(
+        const sp<V3_2::ICameraDeviceCallback>& callback,
+        const ExternalCameraConfig& cfg,
+        const std::vector<SupportedV4L2Format>& sortedFormats,
+        const CroppingType& croppingType,
+        const common::V1_0::helper::CameraMetadata& chars,
+        const std::string& cameraId,
+        unique_fd v4l2Fd) :
+        V3_4::implementation::ExternalCameraDeviceSession(
+                callback, cfg, sortedFormats, croppingType, chars, cameraId, std::move(v4l2Fd)) {
+
+    mCallback_3_5 = nullptr;
+
+    auto castResult = V3_5::ICameraDeviceCallback::castFrom(callback);
+    if (castResult.isOk()) {
+        sp<V3_5::ICameraDeviceCallback> callback3_5 = castResult;
+        if (callback3_5 != nullptr) {
+            mCallback_3_5 = callback3_5;
+        }
+    }
+
+    if (mCallback_3_5 != nullptr) {
+        mSupportBufMgr = true;
+    }
+}
+
+ExternalCameraDeviceSession::~ExternalCameraDeviceSession() {
+    closeOutputThreadImpl();
+}
+
+Return<void> ExternalCameraDeviceSession::configureStreams_3_5(
+        const StreamConfiguration& requestedConfiguration,
+        ICameraDeviceSession::configureStreams_3_5_cb _hidl_cb)  {
+    return configureStreams_3_4(requestedConfiguration.v3_4, _hidl_cb);
+}
+
+Return<void> ExternalCameraDeviceSession::signalStreamFlush(
+        const hidl_vec<int32_t>& /*streamIds*/, uint32_t /*streamConfigCounter*/) {
+    return Void();
+}
+
+Status ExternalCameraDeviceSession::importRequestLocked(
+        const CaptureRequest& request,
+        hidl_vec<buffer_handle_t*>& allBufPtrs,
+        hidl_vec<int>& allFences) {
+    if (mSupportBufMgr) {
+        return importRequestLockedImpl(request, allBufPtrs, allFences, /*allowEmptyBuf*/ true);
+    }
+    return importRequestLockedImpl(request, allBufPtrs, allFences, /*allowEmptyBuf*/ false);
+}
+
+
+ExternalCameraDeviceSession::BufferRequestThread::BufferRequestThread(
+        wp<ExternalCameraDeviceSession> parent,
+        sp<V3_5::ICameraDeviceCallback> callbacks) :
+        mParent(parent),
+        mCallbacks(callbacks) {}
+
+int ExternalCameraDeviceSession::BufferRequestThread::requestBufferStart(
+        const std::vector<HalStreamBuffer>& bufReqs) {
+    if (bufReqs.empty()) {
+        ALOGE("%s: bufReqs is empty!", __FUNCTION__);
+        return -1;
+    }
+
+    {
+        std::lock_guard<std::mutex> lk(mLock);
+        if (mRequestingBuffer) {
+            ALOGE("%s: BufferRequestThread does not support more than one concurrent request!",
+                    __FUNCTION__);
+            return -1;
+        }
+
+        mBufferReqs = bufReqs;
+        mRequestingBuffer = true;
+    }
+    mRequestCond.notify_one();
+    return 0;
+}
+
+int ExternalCameraDeviceSession::BufferRequestThread::waitForBufferRequestDone(
+        std::vector<HalStreamBuffer>* outBufReq) {
+    std::unique_lock<std::mutex> lk(mLock);
+    if (!mRequestingBuffer) {
+        ALOGE("%s: no pending buffer request!", __FUNCTION__);
+        return -1;
+    }
+
+    if (mPendingReturnBufferReqs.empty()) {
+        std::chrono::milliseconds timeout = std::chrono::milliseconds(kReqProcTimeoutMs);
+        auto st = mRequestDoneCond.wait_for(lk, timeout);
+        if (st == std::cv_status::timeout) {
+            ALOGE("%s: wait for buffer request finish timeout!", __FUNCTION__);
+            return -1;
+        }
+    }
+    mRequestingBuffer = false;
+    *outBufReq = std::move(mPendingReturnBufferReqs);
+    mPendingReturnBufferReqs.clear();
+    return 0;
+}
+
+void ExternalCameraDeviceSession::BufferRequestThread::waitForNextRequest() {
+    ATRACE_CALL();
+    std::unique_lock<std::mutex> lk(mLock);
+    int waitTimes = 0;
+    while (mBufferReqs.empty()) {
+        if (exitPending()) {
+            return;
+        }
+        std::chrono::milliseconds timeout = std::chrono::milliseconds(kReqWaitTimeoutMs);
+        auto st = mRequestCond.wait_for(lk, timeout);
+        if (st == std::cv_status::timeout) {
+            waitTimes++;
+            if (waitTimes == kReqWaitTimesWarn) {
+                // BufferRequestThread just wait forever for new buffer request
+                // But it will print some periodic warning indicating it's waiting
+                ALOGV("%s: still waiting for new buffer request", __FUNCTION__);
+                waitTimes = 0;
+            }
+        }
+    }
+
+    // Fill in hidl BufferRequest
+    mHalBufferReqs.resize(mBufferReqs.size());
+    for (size_t i = 0; i < mHalBufferReqs.size(); i++) {
+        mHalBufferReqs[i].streamId = mBufferReqs[i].streamId;
+        mHalBufferReqs[i].numBuffersRequested = 1;
+    }
+}
+
+bool ExternalCameraDeviceSession::BufferRequestThread::threadLoop() {
+    waitForNextRequest();
+    if (exitPending()) {
+        return false;
+    }
+
+    ATRACE_BEGIN("HIDL requestStreamBuffers");
+    BufferRequestStatus status;
+    hidl_vec<StreamBufferRet> bufRets;
+    auto err = mCallbacks->requestStreamBuffers(mHalBufferReqs,
+            [&status, &bufRets]
+            (BufferRequestStatus s, const hidl_vec<StreamBufferRet>& rets) {
+                status = s;
+                bufRets = std::move(rets);
+            });
+    ATRACE_END();
+    if (!err.isOk()) {
+        ALOGE("%s: Transaction error: %s", __FUNCTION__, err.description().c_str());
+        return false;
+    }
+
+    std::unique_lock<std::mutex> lk(mLock);
+    if (status == BufferRequestStatus::OK || status == BufferRequestStatus::FAILED_PARTIAL) {
+        if (bufRets.size() != mHalBufferReqs.size()) {
+            ALOGE("%s: expect %zu buffer requests returned, only got %zu",
+                    __FUNCTION__, mHalBufferReqs.size(), bufRets.size());
+            return false;
+        }
+
+        auto parent = mParent.promote();
+        if (parent == nullptr) {
+            ALOGE("%s: session has been disconnected!", __FUNCTION__);
+            return false;
+        }
+
+        hidl_vec<int> importedFences;
+        importedFences.resize(bufRets.size());
+        for (size_t i = 0; i < bufRets.size(); i++) {
+            int streamId = bufRets[i].streamId;
+            switch (bufRets[i].val.getDiscriminator()) {
+                case StreamBuffersVal::hidl_discriminator::error:
+                    continue;
+                case StreamBuffersVal::hidl_discriminator::buffers: {
+                    const hidl_vec<V3_2::StreamBuffer>& hBufs = bufRets[i].val.buffers();
+                    if (hBufs.size() != 1) {
+                        ALOGE("%s: expect 1 buffer returned, got %zu!", __FUNCTION__, hBufs.size());
+                        return false;
+                    }
+                    const V3_2::StreamBuffer& hBuf = hBufs[0];
+
+                    mBufferReqs[i].bufferId = hBuf.bufferId;
+                    // TODO: create a batch import API so we don't need to lock/unlock mCbsLock
+                    // repeatedly?
+                    lk.unlock();
+                    Status s = parent->importBuffer(streamId,
+                            hBuf.bufferId, hBuf.buffer.getNativeHandle(),
+                            /*out*/&mBufferReqs[i].bufPtr,
+                            /*allowEmptyBuf*/false);
+                    lk.lock();
+
+                    if (s != Status::OK) {
+                        ALOGE("%s: stream %d import buffer failed!", __FUNCTION__, streamId);
+                        cleanupInflightFences(importedFences, i - 1);
+                        return false;
+                    }
+                    if (!sHandleImporter.importFence(hBuf.acquireFence,
+                            mBufferReqs[i].acquireFence)) {
+                        ALOGE("%s: stream %d import fence failed!", __FUNCTION__, streamId);
+                        cleanupInflightFences(importedFences, i - 1);
+                        return false;
+                    }
+                    importedFences[i] = mBufferReqs[i].acquireFence;
+                }
+                break;
+                default:
+                    ALOGE("%s: unkown StreamBuffersVal discrimator!", __FUNCTION__);
+                    return false;
+            }
+        }
+    } else {
+        ALOGE("%s: requestStreamBuffers call failed!", __FUNCTION__);
+    }
+
+    mPendingReturnBufferReqs = std::move(mBufferReqs);
+    mBufferReqs.clear();
+
+    lk.unlock();
+    mRequestDoneCond.notify_one();
+    return true;
+}
+
+void ExternalCameraDeviceSession::initOutputThread() {
+    if (mSupportBufMgr) {
+        mBufferRequestThread = new BufferRequestThread(this, mCallback_3_5);
+        mBufferRequestThread->run("ExtCamBufReq", PRIORITY_DISPLAY);
+    }
+    mOutputThread = new OutputThread(this, mCroppingType, mBufferRequestThread);
+}
+
+void ExternalCameraDeviceSession::closeOutputThreadImpl() {
+    if (mBufferRequestThread) {
+        mBufferRequestThread->requestExit();
+        mBufferRequestThread->join();
+        mBufferRequestThread.clear();
+    }
+}
+
+void ExternalCameraDeviceSession::closeOutputThread() {
+    closeOutputThreadImpl();
+    V3_4::implementation::ExternalCameraDeviceSession::closeOutputThread();
+}
+
+ExternalCameraDeviceSession::OutputThread::OutputThread(
+        wp<ExternalCameraDeviceSession> parent,
+        CroppingType ct,
+        sp<BufferRequestThread> bufReqThread) :
+        V3_4::implementation::ExternalCameraDeviceSession::OutputThread(parent, ct),
+        mBufferRequestThread(bufReqThread) {}
+
+ExternalCameraDeviceSession::OutputThread::~OutputThread() {}
+
+int ExternalCameraDeviceSession::OutputThread::requestBufferStart(
+        const std::vector<HalStreamBuffer>& bufs) {
+    if (mBufferRequestThread != nullptr) {
+        return mBufferRequestThread->requestBufferStart(bufs);
+    }
+    return 0;
+}
+
+int ExternalCameraDeviceSession::OutputThread::waitForBufferRequestDone(
+        /*out*/std::vector<HalStreamBuffer>* outBufs) {
+    if (mBufferRequestThread != nullptr) {
+        return mBufferRequestThread->waitForBufferRequestDone(outBufs);
+    }
+    return 0;
+}
+
+} // namespace implementation
+}  // namespace V3_5
+}  // namespace device
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
diff --git a/camera/device/3.5/default/include/ext_device_v3_5_impl/ExternalCameraDeviceSession.h b/camera/device/3.5/default/include/ext_device_v3_5_impl/ExternalCameraDeviceSession.h
new file mode 100644
index 0000000..4d2d6b7
--- /dev/null
+++ b/camera/device/3.5/default/include/ext_device_v3_5_impl/ExternalCameraDeviceSession.h
@@ -0,0 +1,256 @@
+/*
+ * Copyright (C) 2018 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_CAMERA_DEVICE_V3_5_EXTCAMERADEVICE3SESSION_H
+#define ANDROID_HARDWARE_CAMERA_DEVICE_V3_5_EXTCAMERADEVICE3SESSION_H
+
+#include <android/hardware/camera/device/3.5/ICameraDeviceCallback.h>
+#include <android/hardware/camera/device/3.5/ICameraDeviceSession.h>
+#include <../../3.4/default/include/ext_device_v3_4_impl/ExternalCameraDeviceSession.h>
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace device {
+namespace V3_5 {
+namespace implementation {
+
+using ::android::hardware::camera::device::V3_2::BufferCache;
+using ::android::hardware::camera::device::V3_5::BufferRequest;
+using ::android::hardware::camera::device::V3_5::BufferRequestStatus;
+using ::android::hardware::camera::device::V3_2::BufferStatus;
+using ::android::hardware::camera::device::V3_2::CameraMetadata;
+using ::android::hardware::camera::device::V3_2::CaptureRequest;
+using ::android::hardware::camera::device::V3_2::CaptureResult;
+using ::android::hardware::camera::device::V3_2::ErrorCode;
+using ::android::hardware::camera::device::V3_5::ICameraDeviceCallback;
+using ::android::hardware::camera::device::V3_2::MsgType;
+using ::android::hardware::camera::device::V3_2::NotifyMsg;
+using ::android::hardware::camera::device::V3_2::RequestTemplate;
+using ::android::hardware::camera::device::V3_2::Stream;
+using ::android::hardware::camera::device::V3_5::StreamConfiguration;
+using ::android::hardware::camera::device::V3_2::StreamConfigurationMode;
+using ::android::hardware::camera::device::V3_2::StreamRotation;
+using ::android::hardware::camera::device::V3_2::StreamType;
+using ::android::hardware::camera::device::V3_2::DataspaceFlags;
+using ::android::hardware::camera::device::V3_2::CameraBlob;
+using ::android::hardware::camera::device::V3_2::CameraBlobId;
+using ::android::hardware::camera::device::V3_4::HalStreamConfiguration;
+using ::android::hardware::camera::device::V3_5::ICameraDeviceSession;
+using ::android::hardware::camera::common::V1_0::Status;
+using ::android::hardware::camera::common::V1_0::helper::HandleImporter;
+using ::android::hardware::camera::common::V1_0::helper::ExifUtils;
+using ::android::hardware::camera::external::common::ExternalCameraConfig;
+using ::android::hardware::camera::external::common::Size;
+using ::android::hardware::camera::external::common::SizeHasher;
+using ::android::hardware::graphics::common::V1_0::BufferUsage;
+using ::android::hardware::graphics::common::V1_0::Dataspace;
+using ::android::hardware::graphics::common::V1_0::PixelFormat;
+using ::android::hardware::kSynchronizedReadWrite;
+using ::android::hardware::MessageQueue;
+using ::android::hardware::MQDescriptorSync;
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+using ::android::hardware::hidl_vec;
+using ::android::hardware::hidl_string;
+using ::android::sp;
+using ::android::Mutex;
+using ::android::base::unique_fd;
+
+using ::android::hardware::camera::device::V3_4::implementation::SupportedV4L2Format;
+using ::android::hardware::camera::device::V3_4::implementation::CroppingType;
+
+struct ExternalCameraDeviceSession : public V3_4::implementation::ExternalCameraDeviceSession {
+
+    ExternalCameraDeviceSession(const sp<V3_2::ICameraDeviceCallback>&,
+            const ExternalCameraConfig& cfg,
+            const std::vector<SupportedV4L2Format>& sortedFormats,
+            const CroppingType& croppingType,
+            const common::V1_0::helper::CameraMetadata& chars,
+            const std::string& cameraId,
+            unique_fd v4l2Fd);
+    virtual ~ExternalCameraDeviceSession();
+
+    // Retrieve the HIDL interface, split into its own class to avoid inheritance issues when
+    // dealing with minor version revs and simultaneous implementation and interface inheritance
+    virtual sp<V3_4::ICameraDeviceSession> getInterface() override {
+        return new TrampolineSessionInterface_3_5(this);
+    }
+
+protected:
+    // Methods from v3.4 and earlier will trampoline to inherited implementation
+    Return<void> configureStreams_3_5(
+            const StreamConfiguration& requestedConfiguration,
+            ICameraDeviceSession::configureStreams_3_5_cb _hidl_cb);
+
+    Return<void> signalStreamFlush(
+            const hidl_vec<int32_t>& requests,
+            uint32_t streamConfigCounter);
+
+    virtual void initOutputThread() override;
+    virtual void closeOutputThread() override;
+    void closeOutputThreadImpl();
+
+    virtual Status importRequestLocked(
+            const CaptureRequest& request,
+            hidl_vec<buffer_handle_t*>& allBufPtrs,
+            hidl_vec<int>& allFences) override;
+
+    class BufferRequestThread : public android::Thread {
+    public:
+        BufferRequestThread(
+                wp<ExternalCameraDeviceSession> parent,
+                sp<V3_5::ICameraDeviceCallback> callbacks);
+
+        int requestBufferStart(const std::vector<HalStreamBuffer>&);
+        int waitForBufferRequestDone(
+                /*out*/std::vector<HalStreamBuffer>*);
+
+        virtual bool threadLoop() override;
+
+    private:
+        void waitForNextRequest();
+
+        const wp<ExternalCameraDeviceSession> mParent;
+        const sp<V3_5::ICameraDeviceCallback> mCallbacks;
+
+        std::mutex mLock;
+        bool mRequestingBuffer = false;
+
+        std::vector<HalStreamBuffer> mBufferReqs;
+        std::vector<HalStreamBuffer> mPendingReturnBufferReqs;
+        // mHalBufferReqs is not under mLock protection during the HIDL transaction
+        hidl_vec<BufferRequest>      mHalBufferReqs;
+
+        // request buffers takes much less time in steady state, but can take much longer
+        // when requesting 1st buffer from a stream.
+        // TODO: consider a separate timeout for new vs. steady state?
+        // TODO: or make sure framework is warming up the pipeline during configure new stream?
+        static const int kReqProcTimeoutMs = 66;
+
+        static const int kReqWaitTimeoutMs = 33;
+        static const int kReqWaitTimesWarn = 90;  // 33ms * 90 ~= 3 sec
+        std::condition_variable mRequestCond;     // signaled when a new buffer request incoming
+        std::condition_variable mRequestDoneCond; // signaled when a request is done
+    };
+
+    sp<BufferRequestThread> mBufferRequestThread;
+
+    class OutputThread :
+            public V3_4::implementation::ExternalCameraDeviceSession::OutputThread {
+    public:
+        // TODO: pass buffer request thread to OutputThread ctor
+        OutputThread(wp<ExternalCameraDeviceSession> parent, CroppingType,
+                sp<BufferRequestThread> bufReqThread);
+        virtual ~OutputThread();
+
+    protected:
+        // Methods to request output buffer in parallel
+        virtual int requestBufferStart(const std::vector<HalStreamBuffer>&) override;
+        virtual int waitForBufferRequestDone(
+                /*out*/std::vector<HalStreamBuffer>*) override;
+
+        const sp<BufferRequestThread> mBufferRequestThread;
+    };
+
+    sp<V3_5::ICameraDeviceCallback> mCallback_3_5;
+    bool mSupportBufMgr;
+
+private:
+
+    struct TrampolineSessionInterface_3_5 : public ICameraDeviceSession {
+        TrampolineSessionInterface_3_5(sp<ExternalCameraDeviceSession> parent) :
+                mParent(parent) {}
+
+        virtual Return<void> constructDefaultRequestSettings(
+                RequestTemplate type,
+                V3_3::ICameraDeviceSession::constructDefaultRequestSettings_cb _hidl_cb) override {
+            return mParent->constructDefaultRequestSettings(type, _hidl_cb);
+        }
+
+        virtual Return<void> configureStreams(
+                const V3_2::StreamConfiguration& requestedConfiguration,
+                V3_3::ICameraDeviceSession::configureStreams_cb _hidl_cb) override {
+            return mParent->configureStreams(requestedConfiguration, _hidl_cb);
+        }
+
+        virtual Return<void> processCaptureRequest(const hidl_vec<V3_2::CaptureRequest>& requests,
+                const hidl_vec<V3_2::BufferCache>& cachesToRemove,
+                V3_3::ICameraDeviceSession::processCaptureRequest_cb _hidl_cb) override {
+            return mParent->processCaptureRequest(requests, cachesToRemove, _hidl_cb);
+        }
+
+        virtual Return<void> getCaptureRequestMetadataQueue(
+                V3_3::ICameraDeviceSession::getCaptureRequestMetadataQueue_cb _hidl_cb) override  {
+            return mParent->getCaptureRequestMetadataQueue(_hidl_cb);
+        }
+
+        virtual Return<void> getCaptureResultMetadataQueue(
+                V3_3::ICameraDeviceSession::getCaptureResultMetadataQueue_cb _hidl_cb) override  {
+            return mParent->getCaptureResultMetadataQueue(_hidl_cb);
+        }
+
+        virtual Return<Status> flush() override {
+            return mParent->flush();
+        }
+
+        virtual Return<void> close() override {
+            return mParent->close();
+        }
+
+        virtual Return<void> configureStreams_3_3(
+                const V3_2::StreamConfiguration& requestedConfiguration,
+                configureStreams_3_3_cb _hidl_cb) override {
+            return mParent->configureStreams_3_3(requestedConfiguration, _hidl_cb);
+        }
+
+        virtual Return<void> configureStreams_3_4(
+                const V3_4::StreamConfiguration& requestedConfiguration,
+                configureStreams_3_4_cb _hidl_cb) override {
+            return mParent->configureStreams_3_4(requestedConfiguration, _hidl_cb);
+        }
+
+        virtual Return<void> processCaptureRequest_3_4(const hidl_vec<V3_4::CaptureRequest>& requests,
+                const hidl_vec<V3_2::BufferCache>& cachesToRemove,
+                ICameraDeviceSession::processCaptureRequest_3_4_cb _hidl_cb) override {
+            return mParent->processCaptureRequest_3_4(requests, cachesToRemove, _hidl_cb);
+        }
+
+        virtual Return<void> configureStreams_3_5(
+                const StreamConfiguration& requestedConfiguration,
+                configureStreams_3_5_cb _hidl_cb) override {
+            return mParent->configureStreams_3_5(requestedConfiguration, _hidl_cb);
+        }
+
+        virtual Return<void> signalStreamFlush(
+                const hidl_vec<int32_t>& requests,
+                uint32_t streamConfigCounter) override {
+            return mParent->signalStreamFlush(requests, streamConfigCounter);
+        }
+
+    private:
+        sp<ExternalCameraDeviceSession> mParent;
+    };
+};
+
+}  // namespace implementation
+}  // namespace V3_5
+}  // namespace device
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
+
+#endif  // ANDROID_HARDWARE_CAMERA_DEVICE_V3_5_EXTCAMERADEVICE3SESSION_H
diff --git a/camera/device/3.5/default/include/ext_device_v3_5_impl/ExternalCameraDevice_3_5.h b/camera/device/3.5/default/include/ext_device_v3_5_impl/ExternalCameraDevice_3_5.h
new file mode 100644
index 0000000..7db86dc
--- /dev/null
+++ b/camera/device/3.5/default/include/ext_device_v3_5_impl/ExternalCameraDevice_3_5.h
@@ -0,0 +1,131 @@
+/*
+ * Copyright (C) 2018 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_CAMERA_DEVICE_V3_5_EXTCAMERADEVICE_H
+#define ANDROID_HARDWARE_CAMERA_DEVICE_V3_5_EXTCAMERADEVICE_H
+
+#include "utils/Mutex.h"
+#include "CameraMetadata.h"
+
+#include <android/hardware/camera/device/3.5/ICameraDevice.h>
+#include <android/hardware/camera/device/3.5/ICameraDeviceCallback.h>
+#include <hidl/Status.h>
+#include <hidl/MQDescriptor.h>
+#include "ExternalCameraDeviceSession.h"
+#include <../../../../3.4/default/include/ext_device_v3_4_impl/ExternalCameraDevice_3_4.h>
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace device {
+namespace V3_5 {
+namespace implementation {
+
+using namespace ::android::hardware::camera::device;
+using ::android::hardware::camera::device::V3_5::ICameraDevice;
+using ::android::hardware::camera::common::V1_0::CameraResourceCost;
+using ::android::hardware::camera::common::V1_0::TorchMode;
+using ::android::hardware::camera::common::V1_0::Status;
+using ::android::hardware::camera::external::common::ExternalCameraConfig;
+using ::android::hardware::camera::external::common::Size;
+using ::android::hardware::Return;
+using ::android::hardware::Void;
+using ::android::hardware::hidl_vec;
+using ::android::hardware::hidl_string;
+using ::android::sp;
+
+/*
+ * The camera device HAL implementation is opened lazily (via the open call)
+ */
+struct ExternalCameraDevice : public V3_4::implementation::ExternalCameraDevice {
+
+    // Called by external camera provider HAL.
+    // Provider HAL must ensure the uniqueness of CameraDevice object per cameraId, or there could
+    // be multiple CameraDevice trying to access the same physical camera.  Also, provider will have
+    // to keep track of all CameraDevice objects in order to notify CameraDevice when the underlying
+    // camera is detached.
+    ExternalCameraDevice(const std::string& cameraId, const ExternalCameraConfig& cfg);
+    virtual ~ExternalCameraDevice();
+
+    virtual sp<V3_2::ICameraDevice> getInterface() override {
+        return new TrampolineDeviceInterface_3_5(this);
+    }
+
+    Return<void> getPhysicalCameraCharacteristics(const hidl_string& physicalCameraId,
+            V3_5::ICameraDevice::getPhysicalCameraCharacteristics_cb _hidl_cb);
+
+protected:
+    virtual sp<V3_4::implementation::ExternalCameraDeviceSession> createSession(
+            const sp<V3_2::ICameraDeviceCallback>&,
+            const ExternalCameraConfig& cfg,
+            const std::vector<SupportedV4L2Format>& sortedFormats,
+            const CroppingType& croppingType,
+            const common::V1_0::helper::CameraMetadata& chars,
+            const std::string& cameraId,
+            unique_fd v4l2Fd) override;
+
+    virtual status_t initDefaultCharsKeys(
+            ::android::hardware::camera::common::V1_0::helper::CameraMetadata*) override;
+
+    const std::vector<int32_t> EXTRA_CHARACTERISTICS_KEYS_3_5 = {
+        ANDROID_INFO_SUPPORTED_BUFFER_MANAGEMENT_VERSION
+    };
+
+private:
+    struct TrampolineDeviceInterface_3_5 : public ICameraDevice {
+        TrampolineDeviceInterface_3_5(sp<ExternalCameraDevice> parent) :
+            mParent(parent) {}
+
+        virtual Return<void> getResourceCost(V3_2::ICameraDevice::getResourceCost_cb _hidl_cb)
+                override {
+            return mParent->getResourceCost(_hidl_cb);
+        }
+
+        virtual Return<void> getCameraCharacteristics(
+                V3_2::ICameraDevice::getCameraCharacteristics_cb _hidl_cb) override {
+            return mParent->getCameraCharacteristics(_hidl_cb);
+        }
+
+        virtual Return<Status> setTorchMode(TorchMode mode) override {
+            return mParent->setTorchMode(mode);
+        }
+
+        virtual Return<void> open(const sp<V3_2::ICameraDeviceCallback>& callback,
+                V3_2::ICameraDevice::open_cb _hidl_cb) override {
+            return mParent->open(callback, _hidl_cb);
+        }
+
+        virtual Return<void> dumpState(const hidl_handle& fd) override {
+            return mParent->dumpState(fd);
+        }
+
+        virtual Return<void> getPhysicalCameraCharacteristics(const hidl_string& physicalCameraId,
+                V3_5::ICameraDevice::getPhysicalCameraCharacteristics_cb _hidl_cb) override {
+            return mParent->getPhysicalCameraCharacteristics(physicalCameraId, _hidl_cb);
+        }
+    private:
+        sp<ExternalCameraDevice> mParent;
+    };
+};
+
+}  // namespace implementation
+}  // namespace V3_5
+}  // namespace device
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
+
+#endif  // ANDROID_HARDWARE_CAMERA_DEVICE_V3_5_EXTCAMERADEVICE_H