audio policy: add routing update client interface

Added IAudioPolicyServiceClient client binder interface
for client process to receive notifications from AudioPolicyService
when audio ports are added/removed or audio patches created/released.

The audio patches owned by a given client are automatically released when
this client binder dies.

Bug: 14815883.

Change-Id: I6013f6aec03b50565cffb1ad2cd1f0f8852032c5
diff --git a/include/media/AudioSystem.h b/include/media/AudioSystem.h
index a79a9ff..6fe0c7f 100644
--- a/include/media/AudioSystem.h
+++ b/include/media/AudioSystem.h
@@ -19,6 +19,7 @@
 
 #include <hardware/audio_effect.h>
 #include <media/IAudioFlingerClient.h>
+#include <media/IAudioPolicyServiceClient.h>
 #include <system/audio.h>
 #include <system/audio_policy.h>
 #include <utils/Errors.h>
@@ -301,6 +302,21 @@
 
     // ----------------------------------------------------------------------------
 
+    class AudioPortCallback : public RefBase
+    {
+    public:
+
+                AudioPortCallback() {}
+        virtual ~AudioPortCallback() {}
+
+        virtual void onAudioPortListUpdate() = 0;
+        virtual void onAudioPatchListUpdate() = 0;
+        virtual void onServiceDied() = 0;
+
+    };
+
+    static void setAudioPortCallback(sp<AudioPortCallback> callBack);
+
 private:
 
     class AudioFlingerClient: public IBinder::DeathRecipient, public BnAudioFlingerClient
@@ -319,7 +335,8 @@
         virtual void ioConfigChanged(int event, audio_io_handle_t ioHandle, const void *param2);
     };
 
-    class AudioPolicyServiceClient: public IBinder::DeathRecipient
+    class AudioPolicyServiceClient: public IBinder::DeathRecipient,
+                                    public BnAudioPolicyServiceClient
     {
     public:
         AudioPolicyServiceClient() {
@@ -327,6 +344,10 @@
 
         // DeathRecipient
         virtual void binderDied(const wp<IBinder>& who);
+
+        // IAudioPolicyServiceClient
+        virtual void onAudioPortListUpdate();
+        virtual void onAudioPatchListUpdate();
     };
 
     static sp<AudioFlingerClient> gAudioFlingerClient;
@@ -349,6 +370,8 @@
     // list of output descriptors containing cached parameters
     // (sampling rate, framecount, channel count...)
     static DefaultKeyedVector<audio_io_handle_t, OutputDescriptor *> gOutputs;
+
+    static sp<AudioPortCallback> gAudioPortCallback;
 };
 
 };  // namespace android