1 /**
2  * Copyright (c) 2018, The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *     http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package android.os;
18 
19 import android.os.ExternalVibration;
20 import android.os.ExternalVibrationScale;
21 
22 /**
23  * The communication channel by which an external system that wants to control the system
24  * vibrator can notify the vibrator subsystem.
25  *
26  * Some vibrators can be driven via multiple paths (e.g. as an audio channel) in addition to
27  * the usual interface, but we typically only want one vibration at a time playing because they
28  * don't mix well. In order to synchronize the two places where vibration might be controlled,
29  * we provide this interface so the vibrator subsystem has a chance to:
30  *
31  * 1) Decide whether the current vibration should play based on the current system policy.
32  * 2) Stop any currently on-going vibrations.
33  * {@hide}
34  */
35 interface IExternalVibratorService {
36     /**
37      * A method called by the external system to start a vibration.
38      *
39      * This returns an {@link ExternalVibrationScale} which includes the vibration scale level and
40      * the adaptive haptics scale.
41      *
42      * If the returned scale level is {@link ExternalVibrationScale.ScaleLevel#SCALE_MUTE}, then
43      * the vibration should <em>not</em> play. If it returns any other scale level, then
44      * any currently playing vibration controlled by the requesting system must be muted and this
45      * vibration can begin playback.
46      *
47      * Note that the IExternalVibratorService implementation will not call mute on any currently
48      * playing external vibrations in order to avoid re-entrancy with the system on the other side.
49      *
50      * @param vib The external vibration starting.
51      * @return {@link ExternalVibrationScale} including scale level and adaptive haptics scale.
52      */
onExternalVibrationStart(in ExternalVibration vib)53     ExternalVibrationScale onExternalVibrationStart(in ExternalVibration vib);
54 
55     /**
56      * A method called by the external system when a vibration no longer wants to play.
57      */
onExternalVibrationStop(in ExternalVibration vib)58     void onExternalVibrationStop(in ExternalVibration vib);
59 }
60