bluetooth/audio/2.0/IBluetoothAudioProvidersFactory.hal

/*
 * Copyright 2018 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.hardware.bluetooth.audio@2.0;

import IBluetoothAudioProvider;

/**
 * This factory allows a HAL implementation to be split into multiple
 * independent providers.
 *
 * When the Bluetooth stack is ready to create an audio session, it must first
 * obtain the IBluetoothAudioProvider for that session type by calling
 * openProvider().
 *
 * Note: For HIDL APIs with a "generates" statement, the callback parameter used
 * for return value must be invoked synchronously before the API call returns.
 */
interface IBluetoothAudioProvidersFactory {

    /**
     * Opens an audio provider for a session type. To close the provider, it is
     * necessary to release references to the returned provider object.
     *
     * @param sessionType The session type (e.g.
     *    A2DP_SOFTWARE_ENCODING_DATAPATH).
     *
     * @return status One of the following
     *    SUCCESS if the Audio HAL successfully opens the provider with the
     *        given session type
     *    FAILURE if the Audio HAL cannot open the provider
     * @return provider The provider of the specified session type
     */
    openProvider(SessionType sessionType)
        generates (Status status, IBluetoothAudioProvider provider);

    /**
     * Gets a list of audio capabilities for a session type.
     *
     * For software encoding, the PCM capabilities are returned.
     * For hardware encoding, the supported codecs and their capabilities are
     * returned.
     *
     * @param sessionType The session type (e.g.
     *    A2DP_SOFTWARE_ENCODING_DATAPATH).
     * @return audioCapabilities A list containing all the capabilities
     *    supported by the sesson type. The capabilities is a list of
     *    available options when configuring the codec for the session.
     *    For software encoding it is the PCM data rate.
     *    For hardware encoding it is the list of supported codecs and their
     *    capabilities.
     *    If a provider isn't supported, an empty list should be returned.
     *    Note: Only one entry should exist per codec when using hardware
     *    encoding.
     */
     getProviderCapabilities(SessionType sessionType)
         generates (vec<AudioCapabilities> audioCapabilities);
};