audio policy: refactor audio playback APIs

Refactor audio policy service APIs controlling audio playback (startOutput, stopOutput, releaseOutput)
To allow finer grain control per AudioTrack client.

Test: AudioTrack CTS test. manual test of playback use cases.
Change-Id: I49a681f3c2a8211e524824993049b24d8086376d
diff --git a/media/libaudioclient/AudioSystem.cpp b/media/libaudioclient/AudioSystem.cpp
index c072901..cb4bcfc 100644
--- a/media/libaudioclient/AudioSystem.cpp
+++ b/media/libaudioclient/AudioSystem.cpp
@@ -878,31 +878,25 @@
                                  flags, selectedDeviceId, portId);
 }
 
-status_t AudioSystem::startOutput(audio_io_handle_t output,
-                                  audio_stream_type_t stream,
-                                  audio_session_t session)
+status_t AudioSystem::startOutput(audio_port_handle_t portId)
 {
     const sp<IAudioPolicyService>& aps = AudioSystem::get_audio_policy_service();
     if (aps == 0) return PERMISSION_DENIED;
-    return aps->startOutput(output, stream, session);
+    return aps->startOutput(portId);
 }
 
-status_t AudioSystem::stopOutput(audio_io_handle_t output,
-                                 audio_stream_type_t stream,
-                                 audio_session_t session)
+status_t AudioSystem::stopOutput(audio_port_handle_t portId)
 {
     const sp<IAudioPolicyService>& aps = AudioSystem::get_audio_policy_service();
     if (aps == 0) return PERMISSION_DENIED;
-    return aps->stopOutput(output, stream, session);
+    return aps->stopOutput(portId);
 }
 
-void AudioSystem::releaseOutput(audio_io_handle_t output,
-                                audio_stream_type_t stream,
-                                audio_session_t session)
+void AudioSystem::releaseOutput(audio_port_handle_t portId)
 {
     const sp<IAudioPolicyService>& aps = AudioSystem::get_audio_policy_service();
     if (aps == 0) return;
-    aps->releaseOutput(output, stream, session);
+    aps->releaseOutput(portId);
 }
 
 status_t AudioSystem::getInputForAttr(const audio_attributes_t *attr,
diff --git a/media/libaudioclient/IAudioPolicyService.cpp b/media/libaudioclient/IAudioPolicyService.cpp
index 316105c..9d77376 100644
--- a/media/libaudioclient/IAudioPolicyService.cpp
+++ b/media/libaudioclient/IAudioPolicyService.cpp
@@ -244,41 +244,29 @@
             return status;
         }
 
-    virtual status_t startOutput(audio_io_handle_t output,
-                                 audio_stream_type_t stream,
-                                 audio_session_t session)
+    virtual status_t startOutput(audio_port_handle_t portId)
     {
         Parcel data, reply;
         data.writeInterfaceToken(IAudioPolicyService::getInterfaceDescriptor());
-        data.writeInt32(output);
-        data.writeInt32((int32_t) stream);
-        data.writeInt32((int32_t) session);
+        data.writeInt32((int32_t)portId);
         remote()->transact(START_OUTPUT, data, &reply);
         return static_cast <status_t> (reply.readInt32());
     }
 
-    virtual status_t stopOutput(audio_io_handle_t output,
-                                audio_stream_type_t stream,
-                                audio_session_t session)
+    virtual status_t stopOutput(audio_port_handle_t portId)
     {
         Parcel data, reply;
         data.writeInterfaceToken(IAudioPolicyService::getInterfaceDescriptor());
-        data.writeInt32(output);
-        data.writeInt32((int32_t) stream);
-        data.writeInt32((int32_t) session);
+        data.writeInt32((int32_t)portId);
         remote()->transact(STOP_OUTPUT, data, &reply);
         return static_cast <status_t> (reply.readInt32());
     }
 
-    virtual void releaseOutput(audio_io_handle_t output,
-                               audio_stream_type_t stream,
-                               audio_session_t session)
+    virtual void releaseOutput(audio_port_handle_t portId)
     {
         Parcel data, reply;
         data.writeInterfaceToken(IAudioPolicyService::getInterfaceDescriptor());
-        data.writeInt32(output);
-        data.writeInt32((int32_t)stream);
-        data.writeInt32((int32_t)session);
+        data.writeInt32((int32_t)portId);
         remote()->transact(RELEASE_OUTPUT, data, &reply);
     }
 
@@ -1074,34 +1062,22 @@
 
         case START_OUTPUT: {
             CHECK_INTERFACE(IAudioPolicyService, data, reply);
-            audio_io_handle_t output = static_cast <audio_io_handle_t>(data.readInt32());
-            audio_stream_type_t stream =
-                                static_cast <audio_stream_type_t>(data.readInt32());
-            audio_session_t session = (audio_session_t)data.readInt32();
-            reply->writeInt32(static_cast <uint32_t>(startOutput(output,
-                                                                 stream,
-                                                                 session)));
+            const audio_port_handle_t portId = static_cast <audio_port_handle_t>(data.readInt32());
+            reply->writeInt32(static_cast <uint32_t>(startOutput(portId)));
             return NO_ERROR;
         } break;
 
         case STOP_OUTPUT: {
             CHECK_INTERFACE(IAudioPolicyService, data, reply);
-            audio_io_handle_t output = static_cast <audio_io_handle_t>(data.readInt32());
-            audio_stream_type_t stream =
-                                static_cast <audio_stream_type_t>(data.readInt32());
-            audio_session_t session = (audio_session_t)data.readInt32();
-            reply->writeInt32(static_cast <uint32_t>(stopOutput(output,
-                                                                stream,
-                                                                session)));
+            const audio_port_handle_t portId = static_cast <audio_port_handle_t>(data.readInt32());
+            reply->writeInt32(static_cast <uint32_t>(stopOutput(portId)));
             return NO_ERROR;
         } break;
 
         case RELEASE_OUTPUT: {
             CHECK_INTERFACE(IAudioPolicyService, data, reply);
-            audio_io_handle_t output = static_cast <audio_io_handle_t>(data.readInt32());
-            audio_stream_type_t stream = (audio_stream_type_t)data.readInt32();
-            audio_session_t session = (audio_session_t)data.readInt32();
-            releaseOutput(output, stream, session);
+            const audio_port_handle_t portId = static_cast <audio_port_handle_t>(data.readInt32());
+            releaseOutput(portId);
             return NO_ERROR;
         } break;
 
diff --git a/media/libaudioclient/include/media/AudioSystem.h b/media/libaudioclient/include/media/AudioSystem.h
index 4c0f796..10d6e92 100644
--- a/media/libaudioclient/include/media/AudioSystem.h
+++ b/media/libaudioclient/include/media/AudioSystem.h
@@ -224,15 +224,9 @@
                                      audio_output_flags_t flags,
                                      audio_port_handle_t *selectedDeviceId,
                                      audio_port_handle_t *portId);
-    static status_t startOutput(audio_io_handle_t output,
-                                audio_stream_type_t stream,
-                                audio_session_t session);
-    static status_t stopOutput(audio_io_handle_t output,
-                               audio_stream_type_t stream,
-                               audio_session_t session);
-    static void releaseOutput(audio_io_handle_t output,
-                              audio_stream_type_t stream,
-                              audio_session_t session);
+    static status_t startOutput(audio_port_handle_t portId);
+    static status_t stopOutput(audio_port_handle_t portId);
+    static void releaseOutput(audio_port_handle_t portId);
 
     // Client must successfully hand off the handle reference to AudioFlinger via createRecord(),
     // or release it with releaseInput().
diff --git a/media/libaudioclient/include/media/IAudioPolicyService.h b/media/libaudioclient/include/media/IAudioPolicyService.h
index c3876af..6c017a3 100644
--- a/media/libaudioclient/include/media/IAudioPolicyService.h
+++ b/media/libaudioclient/include/media/IAudioPolicyService.h
@@ -66,15 +66,9 @@
                                       audio_output_flags_t flags,
                                       audio_port_handle_t *selectedDeviceId,
                                       audio_port_handle_t *portId) = 0;
-    virtual status_t startOutput(audio_io_handle_t output,
-                                 audio_stream_type_t stream,
-                                 audio_session_t session) = 0;
-    virtual status_t stopOutput(audio_io_handle_t output,
-                                audio_stream_type_t stream,
-                                audio_session_t session) = 0;
-    virtual void releaseOutput(audio_io_handle_t output,
-                               audio_stream_type_t stream,
-                               audio_session_t session) = 0;
+    virtual status_t startOutput(audio_port_handle_t portId) = 0;
+    virtual status_t stopOutput(audio_port_handle_t portId) = 0;
+    virtual void releaseOutput(audio_port_handle_t portId) = 0;
     virtual status_t  getInputForAttr(const audio_attributes_t *attr,
                               audio_io_handle_t *input,
                               audio_session_t session,