AudioManager: Bluetooth latency mode control

Add System APIs to discover support and control the use
of latency mode control over Bluetooth link.

Bug: 257922898
Test: make

Merged-In: Ifca58e6b95abf95f98f5e202172b3e36021fcf6e
Change-Id: Ifca58e6b95abf95f98f5e202172b3e36021fcf6e
diff --git a/core/api/system-current.txt b/core/api/system-current.txt
index 9ff0afe..6eddc3c0 100644
--- a/core/api/system-current.txt
+++ b/core/api/system-current.txt
@@ -6189,6 +6189,7 @@
     method @NonNull @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public int[] getSupportedSystemUsages();
     method @IntRange(from=0) @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public int getVolumeIndexForAttributes(@NonNull android.media.AudioAttributes);
     method public boolean isAudioServerRunning();
+    method @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public boolean isBluetoothVariableLatencyEnabled();
     method public boolean isHdmiSystemAudioSupported();
     method @RequiresPermission(android.Manifest.permission.CALL_AUDIO_INTERCEPTION) public boolean isPstnCallAudioInterceptable();
     method @RequiresPermission(android.Manifest.permission.ACCESS_ULTRASOUND) public boolean isUltrasoundSupported();
@@ -6207,6 +6208,7 @@
     method @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public void setActiveAssistantServiceUids(@NonNull int[]);
     method @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public boolean setAdditionalOutputDeviceDelay(@NonNull android.media.AudioDeviceInfo, @IntRange(from=0) long);
     method public void setAudioServerStateCallback(@NonNull java.util.concurrent.Executor, @NonNull android.media.AudioManager.AudioServerStateCallback);
+    method @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public void setBluetoothVariableLatencyEnabled(boolean);
     method @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public void setDeviceVolumeBehavior(@NonNull android.media.AudioDeviceAttributes, int);
     method @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public void setFocusRequestResult(@NonNull android.media.AudioFocusInfo, int, @NonNull android.media.audiopolicy.AudioPolicy);
     method @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public boolean setPreferredDeviceForCapturePreset(int, @NonNull android.media.AudioDeviceAttributes);
@@ -6214,6 +6216,7 @@
     method @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public boolean setPreferredDevicesForStrategy(@NonNull android.media.audiopolicy.AudioProductStrategy, @NonNull java.util.List<android.media.AudioDeviceAttributes>);
     method @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public void setSupportedSystemUsages(@NonNull int[]);
     method @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public void setVolumeIndexForAttributes(@NonNull android.media.AudioAttributes, int, int);
+    method @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public boolean supportsBluetoothVariableLatency();
     method @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public void unregisterAudioPolicy(@NonNull android.media.audiopolicy.AudioPolicy);
     method @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public void unregisterAudioPolicyAsync(@NonNull android.media.audiopolicy.AudioPolicy);
     method @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING) public void unregisterMuteAwaitConnectionCallback(@NonNull android.media.AudioManager.MuteAwaitConnectionCallback);
diff --git a/core/jni/android_media_AudioSystem.cpp b/core/jni/android_media_AudioSystem.cpp
index 77317d1..47057a4 100644
--- a/core/jni/android_media_AudioSystem.cpp
+++ b/core/jni/android_media_AudioSystem.cpp
@@ -2952,6 +2952,30 @@
     return jStatus;
 }
 
+static jboolean android_media_AudioSystem_supportsBluetoothVariableLatency(JNIEnv *env,
+                                                                           jobject thiz) {
+    bool supports;
+    if (AudioSystem::supportsBluetoothVariableLatency(&supports) != NO_ERROR) {
+        supports = false;
+    }
+    return supports;
+}
+
+static int android_media_AudioSystem_setBluetoothVariableLatencyEnabled(JNIEnv *env, jobject thiz,
+                                                                        jboolean enabled) {
+    return (jint)check_AudioSystem_Command(
+            AudioSystem::setBluetoothVariableLatencyEnabled(enabled));
+}
+
+static jboolean android_media_AudioSystem_isBluetoothVariableLatencyEnabled(JNIEnv *env,
+                                                                            jobject thiz) {
+    bool enabled;
+    if (AudioSystem::isBluetoothVariableLatencyEnabled(&enabled) != NO_ERROR) {
+        enabled = false;
+    }
+    return enabled;
+}
+
 // ----------------------------------------------------------------------------
 
 static const JNINativeMethod gMethods[] =
@@ -3104,7 +3128,13 @@
           (void *)android_media_AudioSystem_getDirectPlaybackSupport},
          {"getDirectProfilesForAttributes",
           "(Landroid/media/AudioAttributes;Ljava/util/ArrayList;)I",
-          (void *)android_media_AudioSystem_getDirectProfilesForAttributes}};
+          (void *)android_media_AudioSystem_getDirectProfilesForAttributes},
+         {"supportsBluetoothVariableLatency", "()Z",
+          (void *)android_media_AudioSystem_supportsBluetoothVariableLatency},
+         {"setBluetoothVariableLatencyEnabled", "(Z)I",
+          (void *)android_media_AudioSystem_setBluetoothVariableLatencyEnabled},
+         {"isBluetoothVariableLatencyEnabled", "()Z",
+          (void *)android_media_AudioSystem_isBluetoothVariableLatencyEnabled}};
 
 static const JNINativeMethod gEventHandlerMethods[] = {
     {"native_setup",
diff --git a/media/java/android/media/AudioManager.java b/media/java/android/media/AudioManager.java
index 399650d..85911a3 100644
--- a/media/java/android/media/AudioManager.java
+++ b/media/java/android/media/AudioManager.java
@@ -8478,6 +8478,55 @@
         }
     }
 
+    /**
+     * Requests if the implementation supports controlling the latency modes
+     * over the Bluetooth A2DP or LE Audio links.
+     *
+     * @return true if supported, false otherwise
+     *
+     * @hide
+     */
+    @SystemApi
+    @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING)
+    public boolean supportsBluetoothVariableLatency() {
+        try {
+            return getService().supportsBluetoothVariableLatency();
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Enables or disables the variable Bluetooth latency control mechanism in the
+     * audio framework and the audio HAL. This does not apply to the latency mode control
+     * on the spatializer output as this is a built-in feature.
+     *
+     * @hide
+     */
+    @SystemApi
+    @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING)
+    public void setBluetoothVariableLatencyEnabled(boolean enabled) {
+        try {
+            getService().setBluetoothVariableLatencyEnabled(enabled);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
+     * Indicates if the variable Bluetooth latency control mechanism is enabled or disabled.
+     * @hide
+     */
+    @SystemApi
+    @RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING)
+    public boolean isBluetoothVariableLatencyEnabled() {
+        try {
+            return getService().isBluetoothVariableLatencyEnabled();
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
     private final Object mMuteAwaitConnectionListenerLock = new Object();
 
     @GuardedBy("mMuteAwaitConnectionListenerLock")
diff --git a/media/java/android/media/AudioSystem.java b/media/java/android/media/AudioSystem.java
index 097bb41..474ccc9 100644
--- a/media/java/android/media/AudioSystem.java
+++ b/media/java/android/media/AudioSystem.java
@@ -2428,4 +2428,30 @@
      * Keep in sync with core/jni/android_media_DeviceCallback.h.
      */
     final static int NATIVE_EVENT_ROUTING_CHANGE = 1000;
+
+
+    /**
+     * Requests if the implementation supports controlling the latency modes
+     * over the Bluetooth A2DP or LE Audio links.
+     *
+     * @return true if supported, false otherwise
+     *
+     * @hide
+     */
+    public static native boolean supportsBluetoothVariableLatency();
+
+    /**
+     * Enables or disables the variable Bluetooth latency control mechanism in the
+     * audio framework and the audio HAL. This does not apply to the latency mode control
+     * on the spatializer output as this is a built-in feature.
+     *
+     * @hide
+     */
+    public static native int setBluetoothVariableLatencyEnabled(boolean enabled);
+
+    /**
+     * Indicates if the variable Bluetooth latency control mechanism is enabled or disabled.
+     * @hide
+     */
+    public static native boolean isBluetoothVariableLatencyEnabled();
 }
diff --git a/media/java/android/media/IAudioService.aidl b/media/java/android/media/IAudioService.aidl
index cfcd79a..9375a0d 100644
--- a/media/java/android/media/IAudioService.aidl
+++ b/media/java/android/media/IAudioService.aidl
@@ -517,4 +517,16 @@
             boolean handlesvolumeAdjustment);
 
     AudioHalVersionInfo getHalVersion();
+
+    @EnforcePermission("MODIFY_AUDIO_ROUTING")
+    @JavaPassthrough(annotation="@android.annotation.RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING)")
+    boolean supportsBluetoothVariableLatency();
+
+    @EnforcePermission("MODIFY_AUDIO_ROUTING")
+    @JavaPassthrough(annotation="@android.annotation.RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING)")
+    void setBluetoothVariableLatencyEnabled(boolean enabled);
+
+    @EnforcePermission("MODIFY_AUDIO_ROUTING")
+    @JavaPassthrough(annotation="@android.annotation.RequiresPermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING)")
+    boolean isBluetoothVariableLatencyEnabled();
 }
diff --git a/services/core/java/com/android/server/audio/AudioService.java b/services/core/java/com/android/server/audio/AudioService.java
index 01afd18..e0d324a 100644
--- a/services/core/java/com/android/server/audio/AudioService.java
+++ b/services/core/java/com/android/server/audio/AudioService.java
@@ -124,6 +124,8 @@
 import android.media.audiopolicy.AudioProductStrategy;
 import android.media.audiopolicy.AudioVolumeGroup;
 import android.media.audiopolicy.IAudioPolicyCallback;
+import android.media.permission.ClearCallingIdentityContext;
+import android.media.permission.SafeCloseable;
 import android.media.projection.IMediaProjection;
 import android.media.projection.IMediaProjectionCallback;
 import android.media.projection.IMediaProjectionManager;
@@ -11047,6 +11049,33 @@
         }
     }
 
+    /** @see AudioManager#supportsBluetoothVariableLatency() */
+    @android.annotation.EnforcePermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING)
+    public boolean supportsBluetoothVariableLatency() {
+        super.supportsBluetoothVariableLatency_enforcePermission();
+        try (SafeCloseable ignored = ClearCallingIdentityContext.create()) {
+            return AudioSystem.supportsBluetoothVariableLatency();
+        }
+    }
+
+    /** @see AudioManager#setBluetoothVariableLatencyEnabled(boolean) */
+    @android.annotation.EnforcePermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING)
+    public void setBluetoothVariableLatencyEnabled(boolean enabled) {
+        super.setBluetoothVariableLatencyEnabled_enforcePermission();
+        try (SafeCloseable ignored = ClearCallingIdentityContext.create()) {
+            AudioSystem.setBluetoothVariableLatencyEnabled(enabled);
+        }
+    }
+
+    /** @see AudioManager#isBluetoothVariableLatencyEnabled(boolean) */
+    @android.annotation.EnforcePermission(android.Manifest.permission.MODIFY_AUDIO_ROUTING)
+    public boolean isBluetoothVariableLatencyEnabled() {
+        super.isBluetoothVariableLatencyEnabled_enforcePermission();
+        try (SafeCloseable ignored = ClearCallingIdentityContext.create()) {
+            return AudioSystem.isBluetoothVariableLatencyEnabled();
+        }
+    }
+
     private final Object mExtVolumeControllerLock = new Object();
     private IAudioPolicyCallback mExtVolumeController;
     private void setExtVolumeController(IAudioPolicyCallback apc) {