Merge "RotationHelper: send active displayId to audio HAL" into sc-v2-dev

import android.media.AudioSystem;

import android.os.Handler;

import android.util.Log;

import android.view.Display;

import android.view.Surface;

import android.view.WindowManager;

/**

 * Class to handle device rotation events for AudioService, and forward device rotation

 * to the audio HALs through AudioSystem.

 * and current active ID to the audio HALs through AudioSystem.

 *

 * The role of this class is to monitor device orientation changes, and upon rotation,

 * verify the UI orientation. In case of a change, send the new orientation, in increments

 * of 90deg, through AudioSystem.

 *

 * Another role of this class is to track current active display ID changes. In case of a

 * change, send the new active display ID through AudioSystem.

 *

 * Note that even though we're responding to device orientation events, we always

 * query the display rotation so audio stays in sync with video/dialogs. This is

 * done with .getDefaultDisplay().getRotation() from WINDOW_SERVICE.

 *

 * We also monitor current display ID and audio is able to know which display is active.

 */

class RotationHelper {

    private static AudioDisplayListener sDisplayListener;

    private static final Object sRotationLock = new Object();

    private static final Object sActiveDisplayLock = new Object();

    private static int sDeviceRotation = Surface.ROTATION_0; // R/W synchronized on sRotationLock

    private static int sDisplayId = Display.DEFAULT_DISPLAY; // synchronized on sActiveDisplayLock

    private static Context sContext;

    private static Handler sHandler;

        }

    }

    /**

     * Query current display active id and publish the change if any.

     */

    static void updateActiveDisplayId(int displayId) {

        synchronized (sActiveDisplayLock) {

            if (displayId != Display.DEFAULT_DISPLAY && sDisplayId != displayId) {

                sDisplayId = displayId;

                AudioSystem.setParameters("active_displayId=" + sDisplayId);

            }

        }

    }

    /**

     * Uses android.hardware.display.DisplayManager.DisplayListener

     */

        @Override

        public void onDisplayChanged(int displayId) {

            updateActiveDisplayId(displayId);

            updateOrientation();

        }

    }