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
17package android.hardware.bluetooth.a2dp@1.0;
18
19import IBluetoothAudioHost;
20
21/**
22 * HAL interface for Bluetooth A2DP Offload functionality where
23 * the encoding of the A2DP data packets is offloaded to platform
24 * specific encoders. The A2DP control path is maintained in the
25 * Bluetooth stack.
26 *
27 * This interface is from HAL client to HAL server.
28 *
29 * The HAL client must provide the handle of IBluetoothAudioHost as well
30 * as codec configuration to the HAL server, when its connected to an
31 * active A2DP Sink device. HAL Server, based on the feedback from the Audio
32 * framework must call into the commands provided by the IBluetoothAudioHost.
33 * HAL client must call into IBluetoothAudioOffload to provide the status of
34 * these commands. Once the device becomes inactive, the HAL client must
35 * call the endSession to terminate the session with the HAL server.
36 */
37interface IBluetoothAudioOffload {
38
39    /**
40     * Indicates that the HAL client is connected to an A2DP Sink device
41     * and is ready to stream audio. This function is also used to register
42     * the BluetoothAudioHost interface and the provide the current negotiated
43     * codec.
44     *
45     * |endSession| must be called to unregister the interface.
46     *
47     * @param hostIf interface used to request stream control
48     * @param codecConfig Codec configuration as negotiated with the A2DP Sink
49     *    device
50     * @return status one of the following
51     *    SUCCESS if HAL server successfully initializes the platform with the
52     *        given codec configuration
53     *    UNSUPPORTED_CODEC_CONFIGURATION if HAL server cannot initialize the
54     *        platform with the given codec configuration
55     *    FAILURE if HAL server cannot initialize the platform for any other
56     *        reason
57     */
58    startSession(IBluetoothAudioHost hostIf, CodecConfiguration codecConfig) generates (Status status);
59
60    /**
61     * Updates status for start stream request. The HAL client may need
62     * to communicate to Bluetooth Controller and remote Sink device, in which
63     * case it must update with PENDING status. Once the operation is
64     * completed, it must return with either SUCCESS or FAILURE.
65     *
66     * @param status SUCCESS, FAILURE or PENDING
67     */
68    oneway streamStarted(Status status);
69
70    /**
71     * Updates status for suspend stream request. The HAL client may need
72     * to communicate to Bluetooth Controller and remote device, in which case
73     * it must update with PENDING status. Once the operation is completed, it
74     * must return with either SUCCESS or FAILURE.
75     *
76     * @param status SUCCESS, FAILURE or PENDING
77     */
78    oneway streamSuspended(Status status);
79
80    /**
81     * Ends the current A2DP offload session and unregisters the
82     * BluetoothAudioHost interface.
83     */
84    oneway endSession();
85};
86