Android8.1开机铃声不同步，首次开机无铃声问题

问题描述：客户定制的开机动画是带有开机铃声的，但发现用system/media/bootanimation.ts和/oem/media/bootanimation.zip（包含了audio.wav）的方式都试过，开机(视频)动画没问题，但开机铃声会延迟一两秒。

logcat分析：

D BootAnimation found audio.wav, creating playback engine
04-04 185737.155   371   383 D BootAnimation BootAnimationShownTiming start time 5115ms
04-04 185737.155   371   383 D BootAnimation playing clip for part0, size=2642254
04-04 185737.156   371   395 E libOpenSLES CEngine_Realize binding to audio service failed, service up
04-04 185737.158   371   395 D          PlayerBasePlayerBase()
04-04 185737.158   371   395 E          PlayerBase() binding to audio service f

看开机的logcat，个人理解是播放audio.wav这段音频铃声的时候，audio service服务还没有初始化成功，一直在等待，导致会延迟一点播放。

最终参考了一位网友的文章，顺利解决此问题。修改如下：

frameworks/av/

diff --git a/media/libmediaplayerservice/MediaPlayerService.cpp b/media/libmediaplayerservice/MediaPlayerService.cpp
index bb17943..a1652c2 100755
--- a/media/libmediaplayerservice/MediaPlayerService.cpp
+++ b/media/libmediaplayerservice/MediaPlayerService.cpp
@@ -2622,7 +2622,7 @@ MediaPlayerService::BatteryTracker::BatteryTracker() {
     // reset battery stats
     // if the mediaserver has crashed, battery stats could be left
     // in bad state, reset the state upon service start.
-    BatteryNotifier::getInstance().noteResetVideo();
+    // BatteryNotifier::getInstance().noteResetVideo();
 }
 
 void MediaPlayerService::BatteryTracker::addBatteryData(uint32_t params)
diff --git a/services/audioflinger/AudioFlinger.cpp b/services/audioflinger/AudioFlinger.cpp
old mode 100644
new mode 100755
index ff5f745..b02e74a
--- a/services/audioflinger/AudioFlinger.cpp
+++ b/services/audioflinger/AudioFlinger.cpp
@@ -156,7 +156,7 @@ AudioFlinger::AudioFlinger()
       mIsLowRamDevice(true),
       mIsDeviceTypeKnown(false),
       mGlobalEffectEnableTime(0),
-      mSystemReady(false)
+      mSystemReady(true)
 {
     // unsigned instead of audio_unique_id_use_t, because ++ operator is unavailable for enum
     for (unsigned use = AUDIO_UNIQUE_ID_USE_UNSPECIFIED; use < AUDIO_UNIQUE_ID_USE_MAX; use++) {
diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
old mode 100644
new mode 100755
index a30c460..fb536d6
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -576,11 +576,11 @@ status_t AudioFlinger::ThreadBase::sendConfigEvent_l(sp<ConfigEvent>& event)
 {
     status_t status = NO_ERROR;
 
-    if (event->mRequiresSystemReady && !mSystemReady) {
+/*    if (event->mRequiresSystemReady && !mSystemReady) {
         event->mWaitStatus = false;
         mPendingConfigEvents.add(event);
         return status;
-    }
+    }*/
     mConfigEvents.add(event);
     ALOGV("sendConfigEvent_l() num events %zu event %d", mConfigEvents.size(), event->mType);
     mWaitWorkCV.signal();
@@ -934,7 +934,7 @@ void AudioFlinger::ThreadBase::releaseWakeLock_l()
 }
 
 void AudioFlinger::ThreadBase::getPowerManager_l() {
-    if (mSystemReady && mPowerManager == 0) {
+    if (mPowerManager == 0) {
         // use checkService() to avoid blocking if power service is not up yet
         sp<IBinder> binder =
             defaultServiceManager()->checkService(String16("power"));
@@ -2642,6 +2642,9 @@ ssize_t AudioFlinger::PlaybackThread::threadLoop_write()
     ssize_t bytesWritten;
     const size_t offset = mCurrentWriteLength - mBytesRemaining;
 
+    if (mPowerManager == 0)    
+       acquireWakeLock();
+
     // If an NBAIO sink is present, use it to write the normal mixer's submix
     if (mNormalSink != 0) {

初次开机无开机铃声：

frameworks/av/services/audioflinger/Threads.cpp

@@ -4383,6 +4383,15 @@ AudioFlinger::PlaybackThread::mixer_state AudioFlinger::MixerThread::prepareTrac
                 track->mHasVolumeController = false;
             }
 
+             /*wmc modify start */
+            char mvalue[PROPERTY_VALUE_MAX] = { 1 };
+            property_get("service.bootanim.exit", mvalue, "");
+            if (strcmp(mvalue,"0") == 0){
+                vlf = 0.25f;
+                vrf = 0.25f;
+            }
+            /*wmc modify end */
+
             // For dedicated VoIP outputs, let the HAL apply the stream volume. Track volume is
             // still applied by the mixer.
             if ((mOutput->flags & AUDIO_OUTPUT_FLAG_VOIP_RX) != 0) {