Add channel mask in AudioSink

Add support for specifying a channel mask when opening an AudioSink.
  This parameter does not replace the channel count parameter in order
  to not have to duplicate the logic to derive a mask from the
  channel count everywhere an AudioSink is used without a known mask.

A mask of 0 (CHANNEL_MASK_USE_CHANNEL_ORDER) means a mask will
  be automatically derived from the number of channels.

Update existing AudioSink implementations to use the channel mask,
  and users of AudioSink to specify the mask if available, and
  CHANNEL_MASK_USE_CHANNEL_ORDER otherwise.

Change-Id: Ifa9bd259874816dbc25ead2b03ea52e873cff474

1 files changed, 3 insertions, 1 deletions

diff --git a/include/media/MediaPlayerInterface.h b/include/media/MediaPlayerInterface.h
index f7491d8..8168dff 100644
--- a/include/media/MediaPlayerInterface.h
+++ b/include/media/MediaPlayerInterface.h
@@ -60,6 +60,8 @@ enum player_type {
 #define DEFAULT_AUDIOSINK_BUFFERSIZE 1200
 #define DEFAULT_AUDIOSINK_SAMPLERATE 44100
 
+// when the channel mask isn't known, use the channel count to derive a mask in AudioSink::open()
+#define CHANNEL_MASK_USE_CHANNEL_ORDER 0
 
 // callback mechanism for passing messages to MediaPlayer object
 typedef void (*notify_callback_f)(void* cookie,
@@ -91,7 +93,7 @@ public:
         // If no callback is specified, use the "write" API below to submit
         // audio data.
         virtual status_t    open(
-                uint32_t sampleRate, int channelCount,
+                uint32_t sampleRate, int channelCount, audio_channel_mask_t channelMask,
                 audio_format_t format=AUDIO_FORMAT_PCM_16_BIT,
                 int bufferCount=DEFAULT_AUDIOSINK_BUFFERCOUNT,
                 AudioCallback cb = NULL,