audio policy manager: stream volume per device

Improve volume management by keeping track of volume for each type
of device independently.

AudioPolicyManagerBase now keeps track of stream volumes for each device
and apply volume according to current device selection.
Methods to set and get stream volume now specify the device class.
A value for "default" device is always present for each stream and is used
if a device is selected and no specific volume was ever set for this device.

Change-Id: I06d8f43aa151a09014f7e47e81304c73ff82e9f8

1 files changed, 12 insertions, 6 deletions

diff --git a/include/hardware_legacy/AudioPolicyManagerBase.h b/include/hardware_legacy/AudioPolicyManagerBase.h
index 3ab748d..24368e3 100644
--- a/include/hardware_legacy/AudioPolicyManagerBase.h
+++ b/include/hardware_legacy/AudioPolicyManagerBase.h
@@ -101,8 +101,12 @@ public:
         virtual void initStreamVolume(AudioSystem::stream_type stream,
                                                     int indexMin,
                                                     int indexMax);
-        virtual status_t setStreamVolumeIndex(AudioSystem::stream_type stream, int index);
-        virtual status_t getStreamVolumeIndex(AudioSystem::stream_type stream, int *index);
+        virtual status_t setStreamVolumeIndex(AudioSystem::stream_type stream,
+                                              int index,
+                                              audio_devices_t device);
+        virtual status_t getStreamVolumeIndex(AudioSystem::stream_type stream,
+                                              int *index,
+                                              audio_devices_t device);
 
         // return the strategy corresponding to a given stream type
         virtual uint32_t getStrategyForStream(AudioSystem::stream_type stream);
@@ -219,14 +223,14 @@ protected:
         class StreamDescriptor
         {
         public:
-            StreamDescriptor()
-            :   mIndexMin(0), mIndexMax(1), mIndexCur(1), mCanBeMuted(true) {}
+            StreamDescriptor();
 
-            void dump(char* buffer, size_t size);
+            int getVolumeIndex(audio_devices_t device);
+            void dump(int fd);
 
             int mIndexMin;      // min volume index
             int mIndexMax;      // max volume index
-            int mIndexCur;      // current volume index
+            KeyedVector<audio_devices_t, int> mIndexCur;   // current volume index per device
             bool mCanBeMuted;   // true is the stream can be muted
 
             const VolumeCurvePoint *mVolumeCurve[DEVICE_CATEGORY_CNT];
@@ -340,6 +344,8 @@ protected:
 
         // returns the category the device belongs to with regard to volume curve management
         static device_category getDeviceCategory(uint32_t device);
+        // extract one device relevant for volume control from multiple device selection
+        static audio_devices_t getDeviceForVolume(audio_devices_t device);
 
         AudioPolicyClientInterface *mpClientInterface;  // audio policy client interface
         audio_io_handle_t mHardwareOutput;              // hardware output handler