Handle media button events during phone calls and when ringing

Add functionality in AudioManager/AudioService to register a
 media button receiver for telephony that, when registered, gets
 priority for media button key events during a phone call or
 when ringing.

Bug 6484717

Change-Id: I0835fc02cb24d06ca59af5a32c3ba0ae93e54442

Author: jmtrivi

media/java/android/media/AudioManager.java

@@ -1999,6 +1999,37 @@ public void registerMediaButtonIntent(PendingIntent pi, ComponentName eventRecei
         }
     }
 
+    /**
+     * @hide
+     * Used internally by telephony package to register an intent receiver for ACTION_MEDIA_BUTTON.
+     * @param eventReceiver the component that will receive the media button key events,
+     *          no-op if eventReceiver is null
+     */
+    public void registerMediaButtonEventReceiverForCalls(ComponentName eventReceiver) {
+        if (eventReceiver == null) {
+            return;
+        }
+        IAudioService service = getService();
+        try {
+            // eventReceiver != null
+            service.registerMediaButtonEventReceiverForCalls(eventReceiver);
+        } catch (RemoteException e) {
+            Log.e(TAG, "Dead object in registerMediaButtonEventReceiverForCalls", e);
+        }
+    }
+
+    /**
+     * @hide
+     */
+    public void unregisterMediaButtonEventReceiverForCalls() {
+        IAudioService service = getService();
+        try {
+            service.unregisterMediaButtonEventReceiverForCalls();
+        } catch (RemoteException e) {
+            Log.e(TAG, "Dead object in unregisterMediaButtonEventReceiverForCalls", e);
+        }
+    }
+
     /**
      * Unregister the receiver of MEDIA_BUTTON intents.
      * @param eventReceiver identifier of a {@link android.content.BroadcastReceiver}

media/java/android/media/AudioService.java

@@ -3625,12 +3625,14 @@ private void filterMediaKeyEvent(KeyEvent keyEvent, boolean needWakeLock) {
             Log.e(TAG, "not dispatching invalid media key event " + keyEvent);
             return;
         }
-        // event filtering based on audio mode
+        // event filtering for telephony
         synchronized(mRingingLock) {
-            if (mIsRinging || (getMode() == AudioSystem.MODE_IN_CALL) ||
-                    (getMode() == AudioSystem.MODE_IN_COMMUNICATION) ||
-                    (getMode() == AudioSystem.MODE_RINGTONE) ) {
-                return;
+            synchronized(mRCStack) {
+                if ((mMediaReceiverForCalls != null) &&
+                        (mIsRinging || (getMode() == AudioSystem.MODE_IN_CALL))) {
+                    dispatchMediaKeyEventForCalls(keyEvent, needWakeLock);
+                    return;
+                }
             }
         }
         // event filtering based on voice-based interactions
@@ -3641,6 +3643,25 @@ private void filterMediaKeyEvent(KeyEvent keyEvent, boolean needWakeLock) {
         }
     }
 
+    /**
+     * Handles the dispatching of the media button events to the telephony package.
+     * Precondition: mMediaReceiverForCalls != null
+     * @param keyEvent a non-null KeyEvent whose key code is one of the supported media buttons
+     * @param needWakeLock true if a PARTIAL_WAKE_LOCK needs to be held while this key event
+     *     is dispatched.
+     */
+    private void dispatchMediaKeyEventForCalls(KeyEvent keyEvent, boolean needWakeLock) {
+        Intent keyIntent = new Intent(Intent.ACTION_MEDIA_BUTTON, null);
+        keyIntent.putExtra(Intent.EXTRA_KEY_EVENT, keyEvent);
+        keyIntent.setPackage(mMediaReceiverForCalls.getPackageName());
+        if (needWakeLock) {
+            mMediaEventWakeLock.acquire();
+            keyIntent.putExtra(EXTRA_WAKELOCK_ACQUIRED, WAKELOCK_RELEASE_ON_FINISHED);
+        }
+        mContext.sendOrderedBroadcast(keyIntent, null, mKeyEventDone,
+                mAudioHandler, Activity.RESULT_OK, null, null);
+    }
+
     /**
      * Handles the dispatching of the media button events to one of the registered listeners,
      * or if there was none, broadcast an ACTION_MEDIA_BUTTON intent to the rest of the system.
@@ -4027,6 +4048,12 @@ protected void finalize() throws Throwable {
      */
     private final Stack<RemoteControlStackEntry> mRCStack = new Stack<RemoteControlStackEntry>();
 
+    /**
+     * The component the telephony package can register so telephony calls have priority to
+     * handle media button events
+     */
+    private ComponentName mMediaReceiverForCalls = null;
+
     /**
      * Helper function:
      * Display in the log the current entries in the remote control focus stack
@@ -4380,6 +4407,35 @@ public void unregisterMediaButtonIntent(PendingIntent mediaIntent, ComponentName
         }
     }
 
+    /**
+     * see AudioManager.registerMediaButtonEventReceiverForCalls(ComponentName c)
+     * precondition: c != null
+     */
+    public void registerMediaButtonEventReceiverForCalls(ComponentName c) {
+        if (mContext.checkCallingPermission("android.permission.MODIFY_PHONE_STATE")
+                != PackageManager.PERMISSION_GRANTED) {
+            Log.e(TAG, "Invalid permissions to register media button receiver for calls");
+            return;
+        }
+        synchronized(mRCStack) {
+            mMediaReceiverForCalls = c;
+        }
+    }
+
+    /**
+     * see AudioManager.unregisterMediaButtonEventReceiverForCalls()
+     */
+    public void unregisterMediaButtonEventReceiverForCalls() {
+        if (mContext.checkCallingPermission("android.permission.MODIFY_PHONE_STATE")
+                != PackageManager.PERMISSION_GRANTED) {
+            Log.e(TAG, "Invalid permissions to unregister media button receiver for calls");
+            return;
+        }
+        synchronized(mRCStack) {
+            mMediaReceiverForCalls = null;
+        }
+    }
+
     /**
      * see AudioManager.registerRemoteControlClient(ComponentName eventReceiver, ...)
      * Note: using this method with rcClient == null is a way to "disable" the IRemoteControlClient

media/java/android/media/IAudioService.aidl

@@ -109,6 +109,9 @@ interface IAudioService {
     oneway void registerMediaButtonIntent(in PendingIntent pi, in ComponentName c);
     oneway void unregisterMediaButtonIntent(in PendingIntent pi,  in ComponentName c);
 
+    oneway void registerMediaButtonEventReceiverForCalls(in ComponentName c);
+    oneway void unregisterMediaButtonEventReceiverForCalls();
+
     oneway void registerRemoteControlClient(in PendingIntent mediaIntent,
            in IRemoteControlClient rcClient, in String callingPackageName);
     oneway void unregisterRemoteControlClient(in PendingIntent mediaIntent,