高通CSR QCC300x i2s和AudioCodec 输出切换

一. 以A2DP为例, 并仅分析SBC情况

lib库中的MusicConnectAudio函数

1. 申请local_config内存, 初始化local_config参数

2. InitMultiChannelParams(&(local_config->mch_params));
   决定采样频率

3. DECODER->sink_type: A2DP音乐时参数是 AUDIO_SINK_AV

4. audioDecoderConnectInputSources(DECODER->sink_type, local_config)
   //目标是连接所有的input source到合适的DSP port.
   {
   sources_t sources;

   sources = audioDecoderGetSources(sink_type);
   //sources.source[0] = StreamSourceFromSink(decoder->media_sink); //A2DP 时候, 实际上只得到source[0], 并且来源于空中A2DP的media_sink.

   generalConfiguration(localConfig);

   configureSources(&sources);
   audioDecodeConnectSources(&sources, sink_type, localConfig->content_protection);
   VmalTransformRtpSbcDecode(sources->source[0], StreamKalimbaSink(GetDspPort(0)));
   //创建A2DP 空中source端到KalimbaSink端的实时流媒体转换.GetDspPort(0)=0;
   connectBackChannel(sink_type, localConfig->codec_data);
   }

以上, 主要是连接 A2DP空中的数据到StreamKalimbaSink(0), 并实时转换.
**
6. // Connect up DSP output ports to hardware sinks
audioDecodeConnectDspOutputs(&(local_config->mch_params));
函数实现:

{
   
   
AudioOutputAddSourceOrPanic(StreamKalimbaSource(DSP_OUTPUT_PORT_PRI_LEFT), audio_output_primary_left);
//StreamKalimbaSource(port)