implemented synchronous audio capture

Added the infrastructure to support the synchronization of playback and
capture actions on specific events.
The first requirement for this feature is to synchronize the audio capture
start with the full rendering of a given audio content.
The applications can further be extended to other use cases
(synchronized playback start...) by adding new synchronization events and
new synchronous control methods on player or recorders.

Also added a method to query the audio session from a ToneGenerator.

Change-Id: I51f1167290d9cafdf2fbcdf9e4785156973af44c

1 files changed, 5 insertions, 1 deletions

diff --git a/include/media/AudioRecord.h b/include/media/AudioRecord.h
index 5bfb65b..80d2d72 100644
--- a/include/media/AudioRecord.h
+++ b/include/media/AudioRecord.h
@@ -30,6 +30,7 @@
 #include <utils/threads.h>
 
 #include <system/audio.h>
+#include <media/AudioSystem.h>
 
 namespace android {
 
@@ -215,8 +216,11 @@ public:
 
     /* After it's created the track is not active. Call start() to
      * make it active. If set, the callback will start being called.
+     * if event is not AudioSystem::SYNC_EVENT_NONE, the capture start will be delayed until
+     * the specified event occurs on the specified trigger session.
      */
-            status_t    start();
+            status_t    start(AudioSystem::sync_event_t event = AudioSystem::SYNC_EVENT_NONE,
+                              int triggerSession = 0);
 
     /* Stop a track. If set, the callback will cease being called and
      * obtainBuffer returns STOPPED. Note that obtainBuffer() still works