system/audio_hal_interface/a2dp_encoding.h

/*
 * Copyright 2019 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.
 */

#pragma once

#include <iomanip>
#include <sstream>
#include <vector>

#include "a2dp_error_codes.h"
#include "audio_a2dp_hw/include/audio_a2dp_hw.h"
#include "avdt_api.h"
#include "common/message_loop_thread.h"

namespace bluetooth {
namespace audio {
namespace a2dp {

bool update_codec_offloading_capabilities(
    const std::vector<btav_a2dp_codec_config_t>& framework_preference,
    bool supports_a2dp_hw_offload_v2);

// Check if new bluetooth_audio is enabled
bool is_hal_enabled();

// Check if new bluetooth_audio is running with offloading encoders
bool is_hal_offloading();

// Initialize BluetoothAudio HAL: openProvider
bool init(bluetooth::common::MessageLoopThread* message_loop);

// Clean up BluetoothAudio HAL
void cleanup();

// Set up the codec into BluetoothAudio HAL
bool setup_codec();

// Set low latency buffer mode allowed or disallowed
void set_audio_low_latency_mode_allowed(bool allowed);

// Send command to the BluetoothAudio HAL: StartSession, EndSession,
// StreamStarted, StreamSuspended
void start_session();
void end_session();
void ack_stream_started(const tA2DP_CTRL_ACK& status);
void ack_stream_suspended(const tA2DP_CTRL_ACK& status);

// Read from the FMQ of BluetoothAudio HAL
size_t read(uint8_t* p_buf, uint32_t len);

// Update A2DP delay report to BluetoothAudio HAL
void set_remote_delay(uint16_t delay_report);

// Check whether OPUS is supported
bool is_opus_supported();

// Definitions for A2DP hardware offload codec extensibility.
namespace provider {

// Lookup the codec info in the list of supported offloaded sink codecs.
std::optional<btav_a2dp_codec_index_t> sink_codec_index(
    const uint8_t* p_codec_info);

// Lookup the codec info in the list of supported offloaded source codecs.
std::optional<btav_a2dp_codec_index_t> source_codec_index(
    const uint8_t* p_codec_info);

// Return the name of the codec which is assigned to the input index.
// The codec index must be in the ranges
// BTAV_A2DP_CODEC_INDEX_SINK_EXT_MIN..BTAV_A2DP_CODEC_INDEX_SINK_EXT_MAX or
// BTAV_A2DP_CODEC_INDEX_SOURCE_EXT_MIN..BTAV_A2DP_CODEC_INDEX_SOURCE_EXT_MAX.
// Returns nullopt if the codec_index is not assigned or codec extensibility
// is not supported or enabled.
std::optional<const char*> codec_index_str(btav_a2dp_codec_index_t codec_index);

// Return true if the codec is supported for the session type
// A2DP_HARDWARE_ENCODING_DATAPATH or A2DP_HARDWARE_DECODING_DATAPATH.
bool supports_codec(btav_a2dp_codec_index_t codec_index);

// Return the A2DP capabilities for the selected codec.
// `codec_info` returns the OTA codec capabilities, `codec_config`
// returns the supported capabilities in a generic format.
bool codec_info(btav_a2dp_codec_index_t codec_index, uint64_t* codec_id,
                uint8_t* codec_info, btav_a2dp_codec_config_t* codec_config);

struct a2dp_configuration {
  int remote_seid;
  uint8_t codec_config[AVDT_CODEC_SIZE];
  btav_a2dp_codec_config_t codec_parameters;
  std::vector<uint8_t> vendor_specific_parameters;

  inline std::string toString() const {
    std::ostringstream os;
    os << "A2dpConfiguration{";
    os << "remote_seid: " << remote_seid;
    os << ", codec_index: " << codec_parameters.codec_type;
    os << ", codec_config: {";
    for (int i = 0; i < AVDT_CODEC_SIZE; i++) {
      os << "0x" << std::hex << std::setw(2) << std::setfill('0')
         << static_cast<int>(codec_config[i]);
      if (i != AVDT_CODEC_SIZE - 1) os << ",";
    }
    os << "}";
    os << "}";
    return os.str();
  }
};

struct a2dp_remote_capabilities {
  int seid;
  uint8_t const* capabilities;

  inline std::string toString() const {
    std::ostringstream os;
    os << "A2dpRemoteCapabilities{";
    os << "seid: " << seid;
    os << ", capabilities: {";
    if (capabilities != nullptr) {
      for (int i = 0; i < AVDT_CODEC_SIZE; i++) {
        os << "0x" << std::hex << std::setw(2) << std::setfill('0')
           << static_cast<int>(capabilities[i]);
        if (i != AVDT_CODEC_SIZE - 1) os << ",";
      }
    }
    os << "}";
    os << "}";
    return os.str();
  }
};

// Query the codec selection fromt the audio HAL.
// The HAL is expected to pick the best audio configuration based on the
// discovered remote SEPs.
std::optional<a2dp_configuration> get_a2dp_configuration(
    RawAddress peer_address,
    std::vector<a2dp_remote_capabilities> const& remote_seps,
    btav_a2dp_codec_config_t const& user_preferences);

// Query the codec parameters from the audio HAL.
// The HAL is expected to parse the codec configuration
// received from the peer and decide whether accept
// the it or not.
tA2DP_STATUS parse_a2dp_configuration(
    btav_a2dp_codec_index_t codec_index, const uint8_t* codec_info,
    btav_a2dp_codec_config_t* codec_parameters,
    std::vector<uint8_t>* vendor_specific_parameters);

}  // namespace provider
}  // namespace a2dp
}  // namespace audio
}  // namespace bluetooth