diff --git a/audio/2.0/IStream.hal b/audio/2.0/IStream.hal
index dc43346..5c88a69 100644
--- a/audio/2.0/IStream.hal
+++ b/audio/2.0/IStream.hal
@@ -227,4 +227,56 @@
      * @param fd dump file descriptor.
      */
     debugDump(handle fd);
+
+    /*
+     * Called by the framework to start a stream operating in mmap mode.
+     * createMmapBuffer() must be called before calling start().
+     * Function only implemented by streams operating in mmap mode.
+     *
+     * @return retval OK in case the success.
+     *                NOT_SUPPORTED on non mmap mode streams
+     *                INVALID_STATE if called out of sequence
+     */
+    start() generates (Result retval);
+
+    /**
+     * Called by the framework to stop a stream operating in mmap mode.
+     * Function only implemented by streams operating in mmap mode.
+     *
+     * @return retval OK in case the succes.
+     *                NOT_SUPPORTED on non mmap mode streams
+     *                INVALID_STATE if called out of sequence
+     */
+    stop() generates (Result retval) ;
+
+    /*
+     * Called by the framework to retrieve information on the mmap buffer used for audio
+     * samples transfer.
+     * Function only implemented by streams operating in mmap mode.
+     *
+     * @param minSizeFrames minimum buffer size requested. The actual buffer
+     *                     size returned in struct MmapBufferInfo can be larger.
+     * @return retval OK in case the success.
+     *                NOT_SUPPORTED on non mmap mode streams
+     *                NOT_INITIALIZED in case of memory allocation error
+     *                INVALID_ARGUMENTS if the requested buffer size is too large
+     *                INVALID_STATE if called out of sequence
+     * @return info    a MmapBufferInfo struct containing information on the MMMAP buffer created.
+     */
+    createMmapBuffer(int32_t minSizeFrames)
+            generates (Result retval, MmapBufferInfo info);
+
+    /*
+     * Called by the framework to read current read/write position in the mmap buffer
+     * with associated time stamp.
+     * Function only implemented by streams operating in mmap mode.
+     *
+     * @return retval OK in case the success.
+     *                NOT_SUPPORTED on non mmap mode streams
+     *                INVALID_STATE if called out of sequence
+     * @return position a MmapPosition struct containing current HW read/write position in frames
+     *                  with associated time stamp.
+     */
+    getMmapPosition()
+            generates (Result retval, MmapPosition position);
 };
diff --git a/audio/2.0/default/Android.mk b/audio/2.0/default/Android.mk
index 2b1aa4f..c3cfd69 100644
--- a/audio/2.0/default/Android.mk
+++ b/audio/2.0/default/Android.mk
@@ -33,6 +33,7 @@
     libhidlbase \
     libhidltransport \
     libhwbinder \
+    libcutils \
     libutils \
     libhardware \
     liblog \
diff --git a/audio/2.0/default/Stream.cpp b/audio/2.0/default/Stream.cpp
index 40f67f0..f214eed 100644
--- a/audio/2.0/default/Stream.cpp
+++ b/audio/2.0/default/Stream.cpp
@@ -43,9 +43,10 @@
     mStream = nullptr;
 }
 
+// static
 Result Stream::analyzeStatus(const char* funcName, int status, int ignoreError) {
     if (status != 0 && status != -ignoreError) {
-        ALOGW("Stream %p %s: %s", mStream, funcName, strerror(-status));
+        ALOGW("Error from HAL stream in function %s: %s", funcName, strerror(-status));
     }
     switch (status) {
         case 0: return Result::OK;
@@ -229,6 +230,29 @@
     return Void();
 }
 
+Return<Result>  Stream::start() {
+    return Result::NOT_SUPPORTED;
+}
+
+Return<Result>  Stream::stop() {
+    return Result::NOT_SUPPORTED;
+}
+
+Return<void>  Stream::createMmapBuffer(int32_t minSizeFrames __unused,
+                                       createMmapBuffer_cb _hidl_cb) {
+    Result retval(Result::NOT_SUPPORTED);
+    MmapBufferInfo info;
+    _hidl_cb(retval, info);
+    return Void();
+}
+
+Return<void>  Stream::getMmapPosition(getMmapPosition_cb _hidl_cb) {
+    Result retval(Result::NOT_SUPPORTED);
+    MmapPosition position;
+    _hidl_cb(retval, position);
+    return Void();
+}
+
 } // namespace implementation
 }  // namespace V2_0
 }  // namespace audio
diff --git a/audio/2.0/default/Stream.h b/audio/2.0/default/Stream.h
index 0ebd723..819bbf7 100644
--- a/audio/2.0/default/Stream.h
+++ b/audio/2.0/default/Stream.h
@@ -18,6 +18,7 @@
 #define ANDROID_HARDWARE_AUDIO_V2_0_STREAM_H
 
 #include <android/hardware/audio/2.0/IStream.h>
+#include <hardware/audio.h>
 #include <hidl/Status.h>
 
 #include <hidl/MQDescriptor.h>
@@ -71,9 +72,13 @@
             const hidl_vec<hidl_string>& keys, getParameters_cb _hidl_cb)  override;
     Return<Result> setParameters(const hidl_vec<ParameterValue>& parameters)  override;
     Return<void> debugDump(const hidl_handle& fd)  override;
+    Return<Result> start() override;
+    Return<Result> stop() override;
+    Return<void> createMmapBuffer(int32_t minSizeFrames, createMmapBuffer_cb _hidl_cb) override;
+    Return<void> getMmapPosition(getMmapPosition_cb _hidl_cb) override;
 
     // Utility methods for extending interfaces.
-    Result analyzeStatus(const char* funcName, int status, int ignoreError = OK);
+    static Result analyzeStatus(const char* funcName, int status, int ignoreError = OK);
 
   private:
     audio_stream_t *mStream;
@@ -85,6 +90,80 @@
     int halSetParameters(const char* keysAndValues) override;
 };
 
+
+template <typename T>
+struct StreamMmap : public RefBase {
+    explicit StreamMmap(T* stream) : mStream(stream) {}
+
+    Return<Result> start();
+    Return<Result> stop();
+    Return<void> createMmapBuffer(
+            int32_t minSizeFrames, size_t frameSize, IStream::createMmapBuffer_cb _hidl_cb);
+    Return<void> getMmapPosition(IStream::getMmapPosition_cb _hidl_cb);
+
+ private:
+   StreamMmap() {}
+
+   T *mStream;
+};
+
+template <typename T>
+Return<Result> StreamMmap<T>::start() {
+    if (mStream->start == NULL) return Result::NOT_SUPPORTED;
+    int result = mStream->start(mStream);
+    return Stream::analyzeStatus("start", result);
+}
+
+template <typename T>
+Return<Result> StreamMmap<T>::stop() {
+    if (mStream->stop == NULL) return Result::NOT_SUPPORTED;
+    int result = mStream->stop(mStream);
+    return Stream::analyzeStatus("stop", result);
+}
+
+template <typename T>
+Return<void> StreamMmap<T>::createMmapBuffer(int32_t minSizeFrames, size_t frameSize,
+                                             IStream::createMmapBuffer_cb _hidl_cb) {
+    Result retval(Result::NOT_SUPPORTED);
+    MmapBufferInfo info;
+
+    if (mStream->create_mmap_buffer != NULL) {
+        struct audio_mmap_buffer_info halInfo;
+        retval = Stream::analyzeStatus(
+                "create_mmap_buffer",
+                mStream->create_mmap_buffer(mStream, minSizeFrames, &halInfo));
+        if (retval == Result::OK) {
+            native_handle_t* hidlHandle = native_handle_create(1, 0);
+            hidlHandle->data[0] = halInfo.shared_memory_fd;
+            info.sharedMemory = hidl_memory("audio_buffer", hidlHandle,
+                                            frameSize *halInfo.buffer_size_frames);
+            info.bufferSizeFrames = halInfo.buffer_size_frames;
+            info.burstSizeFrames = halInfo.burst_size_frames;
+        }
+    }
+    _hidl_cb(retval, info);
+    return Void();
+}
+
+template <typename T>
+Return<void> StreamMmap<T>::getMmapPosition(IStream::getMmapPosition_cb _hidl_cb) {
+    Result retval(Result::NOT_SUPPORTED);
+    MmapPosition position;
+
+    if (mStream->get_mmap_position != NULL) {
+        struct audio_mmap_position halPosition;
+        retval = Stream::analyzeStatus(
+                "get_mmap_position",
+                mStream->get_mmap_position(mStream, &halPosition));
+        if (retval == Result::OK) {
+            position.timeNanoseconds = halPosition.time_nanoseconds;
+            position.positionFrames = halPosition.position_frames;
+        }
+    }
+    _hidl_cb(retval, position);
+    return Void();
+}
+
 }  // namespace implementation
 }  // namespace V2_0
 }  // namespace audio
diff --git a/audio/2.0/default/StreamIn.cpp b/audio/2.0/default/StreamIn.cpp
index 1bc9dfb..1441e74 100644
--- a/audio/2.0/default/StreamIn.cpp
+++ b/audio/2.0/default/StreamIn.cpp
@@ -28,7 +28,9 @@
 namespace implementation {
 
 StreamIn::StreamIn(audio_hw_device_t* device, audio_stream_in_t* stream)
-        : mDevice(device), mStream(stream), mStreamCommon(new Stream(&stream->common)) {
+        : mDevice(device), mStream(stream),
+          mStreamCommon(new Stream(&stream->common)),
+          mStreamMmap(new StreamMmap<audio_stream_in_t>(stream)) {
 }
 
 StreamIn::~StreamIn() {
@@ -130,6 +132,22 @@
     return mStreamCommon->debugDump(fd);
 }
 
+Return<Result> StreamIn::start() {
+    return mStreamMmap->start();
+}
+
+Return<Result> StreamIn::stop() {
+    return mStreamMmap->stop();
+}
+
+Return<void> StreamIn::createMmapBuffer(int32_t minSizeFrames, createMmapBuffer_cb _hidl_cb) {
+    return mStreamMmap->createMmapBuffer(
+            minSizeFrames, audio_stream_in_frame_size(mStream), _hidl_cb);
+}
+
+Return<void> StreamIn::getMmapPosition(getMmapPosition_cb _hidl_cb) {
+    return mStreamMmap->getMmapPosition(_hidl_cb);
+}
 
 // Methods from ::android::hardware::audio::V2_0::IStreamIn follow.
 Return<void> StreamIn::getAudioSource(getAudioSource_cb _hidl_cb)  {
@@ -144,7 +162,7 @@
 }
 
 Return<Result> StreamIn::setGain(float gain)  {
-    return mStreamCommon->analyzeStatus("set_gain", mStream->set_gain(mStream, gain));
+    return Stream::analyzeStatus("set_gain", mStream->set_gain(mStream, gain));
 }
 
 Return<void> StreamIn::read(uint64_t size, read_cb _hidl_cb)  {
@@ -157,7 +175,7 @@
         data.resize(readResult);
     } else if (readResult < 0) {
         data.resize(0);
-        retval = mStreamCommon->analyzeStatus("read", readResult);
+        retval = Stream::analyzeStatus("read", readResult);
     }
     _hidl_cb(retval, data);
     return Void();
@@ -172,7 +190,7 @@
     uint64_t frames = 0, time = 0;
     if (mStream->get_capture_position != NULL) {
         int64_t halFrames, halTime;
-        retval = mStreamCommon->analyzeStatus(
+        retval = Stream::analyzeStatus(
                 "get_capture_position",
                 mStream->get_capture_position(mStream, &halFrames, &halTime));
         if (retval == Result::OK) {
diff --git a/audio/2.0/default/StreamIn.h b/audio/2.0/default/StreamIn.h
index f7c17b7..65e94bb 100644
--- a/audio/2.0/default/StreamIn.h
+++ b/audio/2.0/default/StreamIn.h
@@ -80,11 +80,17 @@
     Return<void> read(uint64_t size, read_cb _hidl_cb)  override;
     Return<uint32_t> getInputFramesLost()  override;
     Return<void> getCapturePosition(getCapturePosition_cb _hidl_cb)  override;
+    Return<Result> start() override;
+    Return<Result> stop() override;
+    Return<void> createMmapBuffer(int32_t minSizeFrames, createMmapBuffer_cb _hidl_cb) override;
+    Return<void> getMmapPosition(getMmapPosition_cb _hidl_cb) override;
 
   private:
     audio_hw_device_t *mDevice;
     audio_stream_in_t *mStream;
     sp<Stream> mStreamCommon;
+    sp<StreamMmap<audio_stream_in_t>> mStreamMmap;
+
 
     virtual ~StreamIn();
 };
diff --git a/audio/2.0/default/StreamOut.cpp b/audio/2.0/default/StreamOut.cpp
index 805734b..3d20d11 100644
--- a/audio/2.0/default/StreamOut.cpp
+++ b/audio/2.0/default/StreamOut.cpp
@@ -29,7 +29,9 @@
 namespace implementation {
 
 StreamOut::StreamOut(audio_hw_device_t* device, audio_stream_out_t* stream)
-        : mDevice(device), mStream(stream), mStreamCommon(new Stream(&stream->common)) {
+        : mDevice(device), mStream(stream),
+          mStreamCommon(new Stream(&stream->common)),
+          mStreamMmap(new StreamMmap<audio_stream_out_t>(stream)) {
 }
 
 StreamOut::~StreamOut() {
@@ -133,7 +135,6 @@
     return mStreamCommon->debugDump(fd);
 }
 
-
 // Methods from ::android::hardware::audio::V2_0::IStreamOut follow.
 Return<uint32_t> StreamOut::getLatency()  {
     return mStream->get_latency(mStream);
@@ -142,7 +143,7 @@
 Return<Result> StreamOut::setVolume(float left, float right)  {
     Result retval(Result::NOT_SUPPORTED);
     if (mStream->set_volume != NULL) {
-        retval = mStreamCommon->analyzeStatus(
+        retval = Stream::analyzeStatus(
                 "set_volume", mStream->set_volume(mStream, left, right));
     }
     return retval;
@@ -156,7 +157,7 @@
     if (writeResult >= 0) {
         written = writeResult;
     } else {
-        retval = mStreamCommon->analyzeStatus("write", writeResult);
+        retval = Stream::analyzeStatus("write", writeResult);
         written = 0;
     }
     _hidl_cb(retval, written);
@@ -165,7 +166,7 @@
 
 Return<void> StreamOut::getRenderPosition(getRenderPosition_cb _hidl_cb)  {
     uint32_t halDspFrames;
-    Result retval = mStreamCommon->analyzeStatus(
+    Result retval = Stream::analyzeStatus(
             "get_render_position", mStream->get_render_position(mStream, &halDspFrames));
     _hidl_cb(retval, halDspFrames);
     return Void();
@@ -175,7 +176,7 @@
     Result retval(Result::NOT_SUPPORTED);
     int64_t timestampUs = 0;
     if (mStream->get_next_write_timestamp != NULL) {
-        retval = mStreamCommon->analyzeStatus(
+        retval = Stream::analyzeStatus(
                 "get_next_write_timestamp",
                 mStream->get_next_write_timestamp(mStream, &timestampUs));
     }
@@ -189,7 +190,7 @@
     if (result == 0) {
         mCallback = callback;
     }
-    return mStreamCommon->analyzeStatus("set_callback", result);
+    return Stream::analyzeStatus("set_callback", result);
 }
 
 Return<Result> StreamOut::clearCallback()  {
@@ -228,13 +229,13 @@
 
 Return<Result> StreamOut::pause()  {
     return mStream->pause != NULL ?
-            mStreamCommon->analyzeStatus("pause", mStream->pause(mStream)) :
+            Stream::analyzeStatus("pause", mStream->pause(mStream)) :
             Result::NOT_SUPPORTED;
 }
 
 Return<Result> StreamOut::resume()  {
     return mStream->resume != NULL ?
-            mStreamCommon->analyzeStatus("resume", mStream->resume(mStream)) :
+            Stream::analyzeStatus("resume", mStream->resume(mStream)) :
             Result::NOT_SUPPORTED;
 }
 
@@ -244,14 +245,14 @@
 
 Return<Result> StreamOut::drain(AudioDrain type)  {
     return mStream->drain != NULL ?
-            mStreamCommon->analyzeStatus(
+            Stream::analyzeStatus(
                     "drain", mStream->drain(mStream, static_cast<audio_drain_type_t>(type))) :
             Result::NOT_SUPPORTED;
 }
 
 Return<Result> StreamOut::flush()  {
     return mStream->flush != NULL ?
-            mStreamCommon->analyzeStatus("flush", mStream->flush(mStream)) :
+            Stream::analyzeStatus("flush", mStream->flush(mStream)) :
             Result::NOT_SUPPORTED;
 }
 
@@ -261,7 +262,7 @@
     TimeSpec timeStamp = { 0, 0 };
     if (mStream->get_presentation_position != NULL) {
         struct timespec halTimeStamp;
-        retval = mStreamCommon->analyzeStatus(
+        retval = Stream::analyzeStatus(
                 "get_presentation_position",
                 mStream->get_presentation_position(mStream, &frames, &halTimeStamp),
                 // Don't logspam on EINVAL--it's normal for get_presentation_position
@@ -276,6 +277,23 @@
     return Void();
 }
 
+Return<Result> StreamOut::start() {
+    return mStreamMmap->start();
+}
+
+Return<Result> StreamOut::stop() {
+    return mStreamMmap->stop();
+}
+
+Return<void> StreamOut::createMmapBuffer(int32_t minSizeFrames, createMmapBuffer_cb _hidl_cb) {
+    return mStreamMmap->createMmapBuffer(
+            minSizeFrames, audio_stream_out_frame_size(mStream), _hidl_cb);
+}
+
+Return<void> StreamOut::getMmapPosition(getMmapPosition_cb _hidl_cb) {
+    return mStreamMmap->getMmapPosition(_hidl_cb);
+}
+
 }  // namespace implementation
 }  // namespace V2_0
 }  // namespace audio
diff --git a/audio/2.0/default/StreamOut.h b/audio/2.0/default/StreamOut.h
index dc9a604..9b7f9f8 100644
--- a/audio/2.0/default/StreamOut.h
+++ b/audio/2.0/default/StreamOut.h
@@ -91,11 +91,16 @@
     Return<Result> drain(AudioDrain type)  override;
     Return<Result> flush()  override;
     Return<void> getPresentationPosition(getPresentationPosition_cb _hidl_cb)  override;
+    Return<Result> start() override;
+    Return<Result> stop() override;
+    Return<void> createMmapBuffer(int32_t minSizeFrames, createMmapBuffer_cb _hidl_cb) override;
+    Return<void> getMmapPosition(getMmapPosition_cb _hidl_cb) override;
 
   private:
     audio_hw_device_t *mDevice;
     audio_stream_out_t *mStream;
     sp<Stream> mStreamCommon;
+    sp<StreamMmap<audio_stream_out_t>> mStreamMmap;
     sp<IStreamOutCallback> mCallback;
 
     virtual ~StreamOut();
diff --git a/audio/2.0/types.hal b/audio/2.0/types.hal
index 7002f38..37c39e4 100644
--- a/audio/2.0/types.hal
+++ b/audio/2.0/types.hal
@@ -70,3 +70,22 @@
     string busAddress;      // used for BUS
     string rSubmixAddress;  // used for REMOTE_SUBMIX
 };
+
+/*
+ * Mmap buffer descriptor returned by IStream.createMmapBuffer().
+ * Used by streams opened in mmap mode.
+ */
+struct MmapBufferInfo {
+    memory  sharedMemory;         // mmap memory buffer
+    int32_t bufferSizeFrames;     // total buffer size in frames
+    int32_t burstSizeFrames;      // transfer size granularity in frames
+};
+
+/*
+ * Mmap buffer read/write position returned by IStream.getMmapPosition().
+ * Used by streams opened in mmap mode.
+ */
+struct MmapPosition {
+    int64_t  timeNanoseconds; // time stamp in ns, CLOCK_MONOTONIC
+    int32_t  positionFrames;  // increasing 32 bit frame count reset when IStream.stop() is called
+};