AudioFlinger: Modify flush handling for offload path

Do not allow an offload track to directly control the offload thread
behavior. OffloadThread can check for any pending flush reporting
by its active tracks and decide to flush the HW or not.

Bug: 12530661
Change-Id: Ib33f023c942f6c091b618004136b153c38a6eef6

1 files changed, 12 insertions, 2 deletions

diff --git a/services/audioflinger/Tracks.cpp b/services/audioflinger/Tracks.cpp
index ecedca9..8ffa43e 100644
--- a/services/audioflinger/Tracks.cpp
+++ b/services/audioflinger/Tracks.cpp
@@ -347,7 +347,8 @@ AudioFlinger::PlaybackThread::Track::Track(
     mCachedVolume(1.0),
     mIsInvalid(false),
     mAudioTrackServerProxy(NULL),
-    mResumeToStopping(false)
+    mResumeToStopping(false),
+    mFlushHwPending(false)
 {
     if (mCblk != NULL) {
         if (sharedBuffer == 0) {
@@ -731,6 +732,7 @@ void AudioFlinger::PlaybackThread::Track::flush()
                 mRetryCount = PlaybackThread::kMaxTrackRetriesOffload;
             }
 
+            mFlushHwPending = true;
             mResumeToStopping = false;
         } else {
             if (mState != STOPPING_1 && mState != STOPPING_2 && mState != STOPPED &&
@@ -751,11 +753,19 @@ void AudioFlinger::PlaybackThread::Track::flush()
         // Prevent flush being lost if the track is flushed and then resumed
         // before mixer thread can run. This is important when offloading
         // because the hardware buffer could hold a large amount of audio
-        playbackThread->flushOutput_l();
         playbackThread->broadcast_l();
     }
 }
 
+// must be called with thread lock held
+void AudioFlinger::PlaybackThread::Track::flushAck()
+{
+    if (!isOffloaded())
+        return;
+
+    mFlushHwPending = false;
+}
+
 void AudioFlinger::PlaybackThread::Track::reset()
 {
     // Do not reset twice to avoid discarding data written just after a flush and before