Bug 815452 - Don't unmute FM audio if the user increases the volume when FM audio is muted for channel policy reasons. r=sicking a=basecamp-blocker

b2g/chrome/content/settings.js

@@ -70,7 +70,7 @@ if ("nsIAudioManager" in Ci) {
   const nsIAudioManager = Ci.nsIAudioManager;
   audioChannelSettings = [
     // settings name, max value, apply to stream types
-    ['audio.volume.content', 15, [nsIAudioManager.STREAM_TYPE_SYSTEM, nsIAudioManager.STREAM_TYPE_MUSIC, nsIAudioManager.STREAM_TYPE_FM]],
+    ['audio.volume.content', 15, [nsIAudioManager.STREAM_TYPE_SYSTEM, nsIAudioManager.STREAM_TYPE_MUSIC]],
     ['audio.volume.notification', 15, [nsIAudioManager.STREAM_TYPE_RING, nsIAudioManager.STREAM_TYPE_NOTIFICATION]],
     ['audio.volume.alarm', 15, [nsIAudioManager.STREAM_TYPE_ALARM]],
     ['audio.volume.telephony', 5, [nsIAudioManager.STREAM_TYPE_VOICE_CALL]],

dom/system/gonk/AudioManager.cpp

@@ -391,10 +391,16 @@ NS_IMETHODIMP
 AudioManager::SetStreamVolumeIndex(int32_t aStream, int32_t aIndex) {
   status_t status =
     AudioSystem::setStreamVolumeIndex(static_cast<audio_stream_type_t>(aStream), aIndex);
-  // sync the fm stream volume with music volume
-  if (aStream == AUDIO_STREAM_MUSIC && IsDeviceOn(AUDIO_DEVICE_OUT_FM)) {
+
+  // sync the fm stream volume with music volume, except set fm volume by audioChannelServices
+  if (aStream == AUDIO_STREAM_FM && IsDeviceOn(AUDIO_DEVICE_OUT_FM)) {
+    mFMChannelIsMuted = aIndex == 0;
+  }
+  // sync fm volume with music stream type
+  if (aStream == AUDIO_STREAM_MUSIC && IsDeviceOn(AUDIO_DEVICE_OUT_FM) && !mFMChannelIsMuted) {
     AudioSystem::setStreamVolumeIndex(static_cast<audio_stream_type_t>(AUDIO_STREAM_FM), aIndex);
   }
+
   return status ? NS_ERROR_FAILURE : NS_OK;
 }
 

dom/system/gonk/AudioManager.h

@@ -52,6 +52,7 @@ protected:
 
 private:
   nsAutoPtr<mozilla::hal::SwitchObserver> mObserver;
+  bool mFMChannelIsMuted;
 };
 
 } /* namespace gonk */