From b634e1b6d6bda56128c354b1803b04b537e3799d Mon Sep 17 00:00:00 2001
From: Eric Laurent <elaurent@google.com>
Date: Fri, 1 Aug 2014 14:44:46 -0700
Subject: [PATCH] AudioSystem: add API to query audio HW sync source

Add a method to query from the audio HAL the HW sync
source used for a given audio session.
Add an AudioAttributes flag to request an output with
HW sync source.

Bug: 16132368.
Change-Id: Ic31b2924b98f242c3aa0d58688879f05ea02d6f7
---
 core/jni/android_media_AudioSystem.cpp        |  8 ++++++++
 media/java/android/media/AudioAttributes.java | 10 ++++++++--
 media/java/android/media/AudioSystem.java     |  5 +++++
 3 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/core/jni/android_media_AudioSystem.cpp b/core/jni/android_media_AudioSystem.cpp
index f9da127b56007..33bb90bcdb708 100644
--- a/core/jni/android_media_AudioSystem.cpp
+++ b/core/jni/android_media_AudioSystem.cpp
@@ -1293,6 +1293,12 @@ android_media_AudioSystem_eventHandlerFinalize(JNIEnv *env, jobject thiz)
     AudioSystem::setAudioPortCallback(callback);
 }
 
+static jint
+android_media_AudioSystem_getAudioHwSyncForSession(JNIEnv *env, jobject thiz, jint sessionId)
+{
+    return (jint)AudioSystem::getAudioHwSyncForSession((audio_session_t)sessionId);
+}
+
 // ----------------------------------------------------------------------------
 
 static JNINativeMethod gMethods[] = {
@@ -1332,6 +1338,8 @@ static JNINativeMethod gMethods[] = {
                                                 (void *)android_media_AudioSystem_listAudioPatches},
     {"setAudioPortConfig",   "(Landroid/media/AudioPortConfig;)I",
                                             (void *)android_media_AudioSystem_setAudioPortConfig},
+    {"getAudioHwSyncForSession", "(I)I",
+                                    (void *)android_media_AudioSystem_getAudioHwSyncForSession},
 };
 
 
diff --git a/media/java/android/media/AudioAttributes.java b/media/java/android/media/AudioAttributes.java
index 46fc66b922df1..ce9a74264a599 100644
--- a/media/java/android/media/AudioAttributes.java
+++ b/media/java/android/media/AudioAttributes.java
@@ -152,6 +152,12 @@ public final class AudioAttributes implements Parcelable {
      */
     public final static int FLAG_SCO = 0x1 << 2;
 
+    /**
+     * @hide
+     * CANDIDATE FOR PUBLIC API
+     * Flag requesting the use of an output stream supporting hardware A/V synchronization.
+     */
+    public final static int FLAG_HW_AV_SYNC = 0x1 << 4;
 
     private int mUsage = USAGE_UNKNOWN;
     private int mContentType = CONTENT_TYPE_UNKNOWN;
@@ -196,7 +202,7 @@ public final class AudioAttributes implements Parcelable {
      */
     public int getFlags() {
         // only return the flags that are public
-        return (mFlags & (FLAG_AUDIBILITY_ENFORCED));
+        return (mFlags & (FLAG_AUDIBILITY_ENFORCED | FLAG_HW_AV_SYNC));
     }
 
     /**
@@ -340,7 +346,7 @@ public final class AudioAttributes implements Parcelable {
          */
         public Builder setFlags(int flags) {
             flags &= (AudioAttributes.FLAG_AUDIBILITY_ENFORCED | AudioAttributes.FLAG_SCO
-                    | AudioAttributes.FLAG_SECURE);
+                    | AudioAttributes.FLAG_SECURE | AudioAttributes.FLAG_HW_AV_SYNC);
             mFlags |= flags;
             return this;
         }
diff --git a/media/java/android/media/AudioSystem.java b/media/java/android/media/AudioSystem.java
index 8e2ca95380715..e11aab1df4851 100644
--- a/media/java/android/media/AudioSystem.java
+++ b/media/java/android/media/AudioSystem.java
@@ -487,5 +487,10 @@ public class AudioSystem
     public static native int releaseAudioPatch(AudioPatch patch);
     public static native int listAudioPatches(ArrayList<AudioPatch> patches, int[] generation);
     public static native int setAudioPortConfig(AudioPortConfig config);
+
+    // must be kept in sync with value in include/system/audio.h
+    public static final int AUDIO_HW_SYNC_INVALID = 0;
+
+    public static native int getAudioHwSyncForSession(int sessionId);
 }