audio flinger: pause direct output when underrunning

If a direct output supports pause, pause the stream
instead of placing it into standby when the audio track
underruns. This will avoid resetting the presented frame count
and preserve A/V sync.

Bug: 21437855.

Change-Id: I598346edb62a1864126acdb1d9a937c82eac2191

1 files changed, 7 insertions, 7 deletions

diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index 594ed05..d9b4249 100644
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -4443,7 +4443,7 @@ AudioFlinger::PlaybackThread::mixer_state AudioFlinger::DirectOutputThread::prep
                 track->mRetryCount = kMaxTrackRetriesDirect;
                 mActiveTrack = t;
                 mixerStatus = MIXER_TRACKS_READY;
-                if (usesHwAvSync() && mHwPaused) {
+                if (mHwPaused) {
                     doHwResume = true;
                     mHwPaused = false;
                 }
@@ -4495,7 +4495,7 @@ AudioFlinger::PlaybackThread::mixer_state AudioFlinger::DirectOutputThread::prep
                     android_atomic_or(CBLK_DISABLED, &cblk->mFlags);
                 } else if (last) {
                     mixerStatus = MIXER_TRACKS_ENABLED;
-                    if (usesHwAvSync() && !mHwPaused && !mStandby) {
+                    if (mHwSupportsPause && !mHwPaused && !mStandby) {
                         doHwPause = true;
                         mHwPaused = true;
                     }
@@ -4609,7 +4609,7 @@ bool AudioFlinger::DirectOutputThread::shouldStandby_l()
                            mTracks[mTracks.size() - 1]->mState == TrackBase::IDLE;
     }
 
-    return !mStandby && !(trackPaused || (usesHwAvSync() && mHwPaused && !trackStopped));
+    return !mStandby && !(trackPaused || (mHwPaused && !trackStopped));
 }
 
 // getTrackName_l() must be called with ThreadBase::mLock held
@@ -4715,10 +4715,10 @@ void AudioFlinger::DirectOutputThread::cacheParameters_l()
     // no delay on outputs with HW A/V sync
     if (usesHwAvSync()) {
         standbyDelay = 0;
-    } else if (audio_is_linear_pcm(mFormat)) {
-        standbyDelay = microseconds(activeSleepTime*2);
-    } else {
+    } else if ((mType == OFFLOAD) && !audio_is_linear_pcm(mFormat)) {
         standbyDelay = kOffloadStandbyDelayNs;
+    } else {
+        standbyDelay = microseconds(activeSleepTime*2);
     }
 }
 
@@ -4898,7 +4898,7 @@ AudioFlinger::PlaybackThread::mixer_state AudioFlinger::OffloadThread::prepareTr
         if (track->isPausing()) {
             track->setPaused();
             if (last) {
-                if (!mHwPaused) {
+                if (mHwSupportsPause && !mHwPaused) {
                     doHwPause = true;
                     mHwPaused = true;
                 }