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, 8 insertions, 4 deletions

diff --git a/media/libmedia/AudioSystem.cpp b/media/libmedia/AudioSystem.cpp
index 5193848..d52f8f8 100644
--- a/media/libmedia/AudioSystem.cpp
+++ b/media/libmedia/AudioSystem.cpp
@@ -668,18 +668,22 @@ status_t AudioSystem::initStreamVolume(audio_stream_type_t stream,
     return aps->initStreamVolume(stream, indexMin, indexMax);
 }
 
-status_t AudioSystem::setStreamVolumeIndex(audio_stream_type_t stream, int index)
+status_t AudioSystem::setStreamVolumeIndex(audio_stream_type_t stream,
+                                           int index,
+                                           audio_devices_t device)
 {
     const sp<IAudioPolicyService>& aps = AudioSystem::get_audio_policy_service();
     if (aps == 0) return PERMISSION_DENIED;
-    return aps->setStreamVolumeIndex(stream, index);
+    return aps->setStreamVolumeIndex(stream, index, device);
 }
 
-status_t AudioSystem::getStreamVolumeIndex(audio_stream_type_t stream, int *index)
+status_t AudioSystem::getStreamVolumeIndex(audio_stream_type_t stream,
+                                           int *index,
+                                           audio_devices_t device)
 {
     const sp<IAudioPolicyService>& aps = AudioSystem::get_audio_policy_service();
     if (aps == 0) return PERMISSION_DENIED;
-    return aps->getStreamVolumeIndex(stream, index);
+    return aps->getStreamVolumeIndex(stream, index, device);
 }
 
 uint32_t AudioSystem::getStrategyForStream(audio_stream_type_t stream)