commit 296fb13dd9b5e90d6a05cce897c3b1e7914a478a
author Eric Laurent <elaurent@google.com> Fri May 01 11:38:42 2015 -0700
committer Eric Laurent <elaurent@google.com> Wed May 06 10:14:42 2015 -0700
tree d3ed4e6ff2902da6f556d038c71605c091b75f64
parent 32fa6d0e65dbf956e253a1006e9419dce2fe75c9

Implement audio device callback

Add class AudioSystem::AudioDeviceCallback notifying
AudioSystem clients upon device selection change on a given
input or output thread.
Maintain a list of installed callback per I/O handle in AudioSystem
and call registered callbacks when an OPEN of CONFIG_CHANGED event
is received on IAudioFlingerClient::ioConfigChanged().
Add methods to AudioTrack and AudioRecord to add and remove device
change callbacks.
Add methods to AudioTrack and AudioRecord to query currently selected
device.
ioConfigChanged() events now convey the audio patch describing
the input or output thread routing.

Fix AudioRecord failure to start when invalidation is
handled by start().

Change-Id: I9e938adf025fa712337c63b1e02a8c18f2a20d39

media/libmedia/AudioTrack.cpp

diff --git a/media/libmedia/AudioTrack.cpp b/media/libmedia/AudioTrack.cpp
index bb47d3e..db316b0 100644
--- a/media/libmedia/AudioTrack.cpp
+++ b/media/libmedia/AudioTrack.cpp
@@ -234,6 +234,10 @@
             mAudioTrackThread->requestExitAndWait();
             mAudioTrackThread.clear();
         }
+        // No lock here: worst case we remove a NULL callback which will be a nop
+        if (mDeviceCallback != 0 && mOutput != AUDIO_IO_HANDLE_NONE) {
+            AudioSystem::removeAudioDeviceCallback(mDeviceCallback, mOutput);
+        }
         IInterface::asBinder(mAudioTrack)->unlinkToDeath(mDeathNotifier, this);
         mAudioTrack.clear();
         mCblkMemory.clear();
@@ -1042,6 +1046,14 @@
     return mSelectedDeviceId;
 }
 
+audio_port_handle_t AudioTrack::getRoutedDeviceId() {
+    AutoMutex lock(mLock);
+    if (mOutput == AUDIO_IO_HANDLE_NONE) {
+        return AUDIO_PORT_HANDLE_NONE;
+    }
+    return AudioSystem::getDeviceIdForIo(mOutput);
+}
+
 status_t AudioTrack::attachAuxEffect(int effectId)
 {
     AutoMutex lock(mLock);
@@ -1071,6 +1083,9 @@
         return NO_INIT;
     }
 
+    if (mDeviceCallback != 0 && mOutput != AUDIO_IO_HANDLE_NONE) {
+        AudioSystem::removeAudioDeviceCallback(mDeviceCallback, mOutput);
+    }
     audio_io_handle_t output;
     audio_stream_type_t streamType = mStreamType;
     audio_attributes_t *attr = (mStreamType == AUDIO_STREAM_DEFAULT) ? &mAttributes : NULL;
@@ -1375,6 +1390,10 @@
     mDeathNotifier = new DeathNotifier(this);
     IInterface::asBinder(mAudioTrack)->linkToDeath(mDeathNotifier, this);
 
+    if (mDeviceCallback != 0) {
+        AudioSystem::addAudioDeviceCallback(mDeviceCallback, mOutput);
+    }
+
     return NO_ERROR;
     }
 
@@ -2308,6 +2327,48 @@
     return mProxy->getUnderrunFrames();
 }
 
+status_t AudioTrack::addAudioDeviceCallback(const sp<AudioSystem::AudioDeviceCallback>& callback)
+{
+    if (callback == 0) {
+        ALOGW("%s adding NULL callback!", __FUNCTION__);
+        return BAD_VALUE;
+    }
+    AutoMutex lock(mLock);
+    if (mDeviceCallback == callback) {
+        ALOGW("%s adding same callback!", __FUNCTION__);
+        return INVALID_OPERATION;
+    }
+    status_t status = NO_ERROR;
+    if (mOutput != AUDIO_IO_HANDLE_NONE) {
+        if (mDeviceCallback != 0) {
+            ALOGW("%s callback already present!", __FUNCTION__);
+            AudioSystem::removeAudioDeviceCallback(mDeviceCallback, mOutput);
+        }
+        status = AudioSystem::addAudioDeviceCallback(callback, mOutput);
+    }
+    mDeviceCallback = callback;
+    return status;
+}
+
+status_t AudioTrack::removeAudioDeviceCallback(
+        const sp<AudioSystem::AudioDeviceCallback>& callback)
+{
+    if (callback == 0) {
+        ALOGW("%s removing NULL callback!", __FUNCTION__);
+        return BAD_VALUE;
+    }
+    AutoMutex lock(mLock);
+    if (mDeviceCallback != callback) {
+        ALOGW("%s removing different callback!", __FUNCTION__);
+        return INVALID_OPERATION;
+    }
+    if (mOutput != AUDIO_IO_HANDLE_NONE) {
+        AudioSystem::removeAudioDeviceCallback(mDeviceCallback, mOutput);
+    }
+    mDeviceCallback = 0;
+    return NO_ERROR;
+}
+
 // =========================================================================
 
 void AudioTrack::DeathNotifier::binderDied(const wp<IBinder>& who __unused)