audiopolicy: Add AudioSessionInfo API

 * This patch introduces a new API which allows applications to
   query the state of the audio effects system, and receive
   callbacks with the necessary information to attach effects
   to any stream.
 * In the future, this may come as part of the AudioPort system,
   but since that's an active area of development by Google, we
   will dodge it for now.
 * The policy now simply keeps a refcounted list of objects which
   hold various bits of stream metadata. Callbacks are sent on
   stream open/close to applications which might be listening
   for them.

Change-Id: I2d554d36e1378f4eb7b276010a3bfe8345c22ecd

1 files changed, 29 insertions, 1 deletions

diff --git a/media/libmedia/IAudioPolicyServiceClient.cpp b/media/libmedia/IAudioPolicyServiceClient.cpp
index 65cc7d6..a325996 100644
--- a/media/libmedia/IAudioPolicyServiceClient.cpp
+++ b/media/libmedia/IAudioPolicyServiceClient.cpp
@@ -30,7 +30,8 @@ namespace android {
 enum {
     PORT_LIST_UPDATE = IBinder::FIRST_CALL_TRANSACTION,
     PATCH_LIST_UPDATE,
-    MIX_STATE_UPDATE
+    MIX_STATE_UPDATE,
+    OUTPUT_SESSION_EFFECTS_UPDATE
 };
 
 class BpAudioPolicyServiceClient : public BpInterface<IAudioPolicyServiceClient>
@@ -63,6 +64,19 @@ public:
         data.writeInt32(state);
         remote()->transact(MIX_STATE_UPDATE, data, &reply, IBinder::FLAG_ONEWAY);
     }
+
+    void onOutputSessionEffectsUpdate(sp<AudioSessionInfo>& info, bool added)
+    {
+        Parcel data, reply;
+        data.writeInterfaceToken(IAudioPolicyServiceClient::getInterfaceDescriptor());
+        data.writeInt32(info->mStream);
+        data.writeInt32(info->mSessionId);
+        data.writeInt32(info->mFlags);
+        data.writeInt32(info->mChannelMask);
+        data.writeInt32(info->mUid);
+        data.writeInt32(added ? 1 : 0);
+        remote()->transact(OUTPUT_SESSION_EFFECTS_UPDATE, data, &reply, IBinder::FLAG_ONEWAY);
+    }
 };
 
 IMPLEMENT_META_INTERFACE(AudioPolicyServiceClient, "android.media.IAudioPolicyServiceClient");
@@ -90,6 +104,20 @@ status_t BnAudioPolicyServiceClient::onTransact(
             onDynamicPolicyMixStateUpdate(regId, state);
             return NO_ERROR;
     }
+    case OUTPUT_SESSION_EFFECTS_UPDATE: {
+            CHECK_INTERFACE(IAudioPolicyServiceClient, data, reply);
+            audio_stream_type_t stream = static_cast<audio_stream_type_t>(data.readInt32());
+            audio_session_t sessionId = static_cast<audio_session_t>(data.readInt32());
+            audio_output_flags_t flags = static_cast<audio_output_flags_t>(data.readInt32());
+            audio_channel_mask_t channelMask = static_cast<audio_channel_mask_t>(data.readInt32());
+            uid_t uid = static_cast<uid_t>(data.readInt32());
+            bool added = data.readInt32() > 0;
+
+            sp<AudioSessionInfo> info = new AudioSessionInfo(
+                    sessionId, stream, flags, channelMask, uid);
+            onOutputSessionEffectsUpdate(info, added);
+            return NO_ERROR;
+    }
     default:
         return BBinder::onTransact(code, data, reply, flags);
     }