system/stack/mmc/proto/mmc_config.proto

/*
 * Copyright 2023 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.
 */

syntax = "proto3";

package mmc;

option optimize_for = LITE_RUNTIME;

// union of Lc3 config and codec parameters
message Lc3Param {
  // encoder/decoder config
  int32 dt_us = 1;
  int32 sr_hz = 2;
  int32 sr_pcm_hz = 3;

  // encode/decode parameter
  enum PcmFmt {
    kLc3PcmFormatS16 = 0;
    kLc3PcmFormatS24 = 1;
  }

  PcmFmt fmt = 4;
  int32 stride = 5;
}

// corresponding to SBC_ENC_PARAMS
message SbcEncoderParam {
  enum SamplingFreq {
    kSbcSf16000 = 0;
    kSbcSf32000 = 1;
    kSbcSf44100 = 2;
    kSbcSf48000 = 3;
  }

  enum ChannelMode {
    kSbcMono = 0;
    kSbcDual = 1;
    kSbcStereo = 2;
    kSbcJointStereo = 3;
  }

  enum AllocationMethod {
    kSbcLoudNess = 0;
    kSbcSnr = 1;
  }

  // Default to be kSbcFormatGeneral for SBC if not assigned.
  // Assigning to kSbcFormatMsbc for MSBC.
  enum Format {
    kSbcFormatGeneral = 0;
    kSbcFormatMsbc = 1;
  }

  // encoder config
  int32 num_of_subbands = 1;
  int32 num_of_channels = 2;
  int32 num_of_blocks = 3;
  int32 bit_pool = 4;
  int32 bit_rate = 5;
  SamplingFreq sampling_freq = 6;
  ChannelMode channel_mode = 7;
  AllocationMethod allocation_method = 8;
  Format format = 9;
}

message SbcDecoderParam {
  // decoder config
  int32 max_channels = 1;
  int32 stride = 2;
  bool enhanced = 3;
}

message AacEncoderParam {
  // encoder config
  int32 sample_rate = 1;
  int32 channel_count = 2;
  int32 bit_rate = 3;

  // encode parameter
  int32 bit_depth = 4;
  int32 effective_frame_size = 5;
}

// union of different codec parameters
message ConfigParam {
  // This determines the codec type and whether it is an encoder or a decoder.
  oneof codec_param {
    // HFP LC3 encoder and decoder have same parameter type.
    Lc3Param hfp_lc3_encoder_param = 1;
    Lc3Param hfp_lc3_decoder_param = 2;
    // HFP MSBC use SBC parameters
    SbcEncoderParam hfp_msbc_encoder_param = 3;
    SbcDecoderParam hfp_msbc_decoder_param = 4;
    AacEncoderParam a2dp_aac_encoder_param = 5;
  }
}