audio framework: manage stream volume per device

Improve volume management by keeping track of volume for each type
of device independently.
Volume for each stream (MUSIC, RINGTONE, VOICE_CALL...) is now maintained
per device.

The main changes are:
- AudioService now keeps tracks of stream volumes per device:
 volume indexes are kept in a HashMap < device , index>.
 active device is queried from policy manager when a volume change request
 is received
 initalization, mute and unmute happen on all device simultaneously
- Settings: suffixes is added to volume keys to store each device
volume independently.
- AudioSystem/AudioPolicyService/AudioPolicyInterface: added a device argument
to setStreamVolumeIndex() and getStreamVolumeIndex() to address each
device independently.
- AudioPolicyManagerBase: keep track of stream volumes for each device
and apply volume according to current device selection.

Change-Id: I61ef1c45caadca04d16363bca4140e0f81901b3f

1 files changed, 6 insertions, 2 deletions

diff --git a/include/media/IAudioPolicyService.h b/include/media/IAudioPolicyService.h
index 1ac0bbf..5a4d59b 100644
--- a/include/media/IAudioPolicyService.h
+++ b/include/media/IAudioPolicyService.h
@@ -73,8 +73,12 @@ public:
     virtual status_t initStreamVolume(audio_stream_type_t stream,
                                       int indexMin,
                                       int indexMax) = 0;
-    virtual status_t setStreamVolumeIndex(audio_stream_type_t stream, int index) = 0;
-    virtual status_t getStreamVolumeIndex(audio_stream_type_t stream, int *index) = 0;
+    virtual status_t setStreamVolumeIndex(audio_stream_type_t stream,
+                                          int index,
+                                          audio_devices_t device) = 0;
+    virtual status_t getStreamVolumeIndex(audio_stream_type_t stream,
+                                          int *index,
+                                          audio_devices_t device) = 0;
     virtual uint32_t getStrategyForStream(audio_stream_type_t stream) = 0;
     virtual uint32_t getDevicesForStream(audio_stream_type_t stream) = 0;
     virtual audio_io_handle_t getOutputForEffect(effect_descriptor_t *desc) = 0;