audioflinger: fix offload resume after drain

When pausing and resuming during the drain,
the drain sequence number shuold not be modified
otherwise the drain callback will be ignored.
This causes failure to notify end of stream to audio
player and transition to next song.

Bug: 11247103.
Change-Id: I2a35c5cc3fd6aa667cdd257f9e9cc8715cef5159

1 files changed, 9 insertions, 5 deletions

diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index ba8195e..b8c1632 100644
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -4066,14 +4066,18 @@ AudioFlinger::PlaybackThread::mixer_state AudioFlinger::OffloadThread::prepareTr
                     track->mState = TrackBase::STOPPING_2; // so presentation completes after drain
                     // do not drain if no data was ever sent to HAL (mStandby == true)
                     if (last && !mStandby) {
-                        sleepTime = 0;
-                        standbyTime = systemTime() + standbyDelay;
-                        mixerStatus = MIXER_DRAIN_TRACK;
-                        mDrainSequence += 2;
+                        // do not modify drain sequence if we are already draining. This happens
+                        // when resuming from pause after drain.
+                        if ((mDrainSequence & 1) == 0) {
+                            sleepTime = 0;
+                            standbyTime = systemTime() + standbyDelay;
+                            mixerStatus = MIXER_DRAIN_TRACK;
+                            mDrainSequence += 2;
+                        }
                         if (mHwPaused) {
                             // It is possible to move from PAUSED to STOPPING_1 without
                             // a resume so we must ensure hardware is running
-                            mOutput->stream->resume(mOutput->stream);
+                            doHwResume = true;
                             mHwPaused = false;
                         }
                     }