1/*
2 * Copyright 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
17package android.hardware.bluetooth.audio@2.0;
18
19import IBluetoothAudioPort;
20
21/**
22 * HAL interface from the Bluetooth stack to the Audio HAL
23 *
24 * The Bluetooth stack calls methods in this interface to start and end audio
25 * sessions and sends callback events to the Audio HAL.
26 *
27 * Note: For HIDL APIs with a "generates" statement, the callback parameter used
28 * for return value must be invoked synchronously before the API call returns.
29 */
30interface IBluetoothAudioProvider {
31
32    /**
33     * This method indicates that the Bluetooth stack is ready to stream audio.
34     * It registers an instance of IBluetoothAudioPort with and provides the
35     * current negotiated codec to the Audio HAL. After this method is called,
36     * the Audio HAL can invoke IBluetoothAudioPort.startStream().
37     *
38     * Note: endSession() must be called to unregister this IBluetoothAudioPort
39     *
40     * @param hostIf An instance of IBluetoothAudioPort for stream control
41     * @param audioConfig The audio configuration negotiated with the remote
42     *    device. The PCM parameters are set if software based encoding,
43     *    otherwise the correct codec configuration is used for hardware
44     *    encoding.
45     *
46     * @return status One of the following
47     *    SUCCESS if this IBluetoothAudioPort was successfully registered with
48     *        the Audio HAL
49     *    UNSUPPORTED_CODEC_CONFIGURATION if the Audio HAL cannot register this
50     *        IBluetoothAudioPort with the given codec configuration
51     *    FAILURE if the Audio HAL cannot register this IBluetoothAudioPort for
52     *        any other reason
53     * @return dataMQ The fast message queue for audio data from this provider.
54     *    Audio data will be in PCM format as specified by the
55     *    audioConfig.pcmConfig parameter.
56     *    Invalid if streaming is offloaded to hardware or on failure.
57     */
58    startSession(IBluetoothAudioPort hostIf, AudioConfiguration audioConfig)
59                generates (Status status, fmq_sync<uint8_t> dataMQ);
60
61    /**
62     * Callback for IBluetoothAudioPort.startStream()
63     *
64     * @param status SUCCESS or FAILURE
65     */
66    streamStarted(Status status);
67
68    /**
69     * Callback for IBluetoothAudioPort.suspendStream()
70     *
71     * @param status SUCCESS or FAILURE
72     */
73    streamSuspended(Status status);
74
75    /**
76     * Ends the current session and unregisters the IBluetoothAudioPort
77     * interface.
78     */
79    endSession();
80};
81