csr8675 adk4.1 source工程codec指示

static void a2dp_msg_media_open_cfm(const A2DP_MEDIA_OPEN_CFM_T *message)
{
    a2dpInstance *inst = a2dp_get_instance_from_device_id(message->device_id);
    
    if (inst == NULL)
    {
        A2DP_MSG_DEBUG(("  inst not found\n"));
        return;
    }
    
    A2DP_MSG_DEBUG_INST(inst);
    
    switch (a2dp_get_state(inst))
    {
        case A2DP_STATE_CONNECTING_MEDIA_LOCAL:
        case A2DP_STATE_CONNECTING_MEDIA_REMOTE:        
        {           
            if (message->status == a2dp_success)
            {
                a2dp_codec_settings *settings = NULL;
                /* store the device_id for this signalling connection */
                inst->a2dp_stream_id = message->stream_id;
                A2DP_MSG_DEBUG(("  device ID:[0x%x]\n", message->device_id)); 
                A2DP_MSG_DEBUG(("  stream ID [0x%x]\n", message->stream_id));

                settings = A2dpCodecGetSettings(message->device_id, message->stream_id);
                           
                if (settings)
                {
                    A2DP_MSG_DEBUG(("  stream end point ID [0x%x]\n", settings->seid));/*位置在这里*/
                    /* update the audio plugin in use */
                    audio_a2dp_set_plugin(settings->seid);                    
                    /* free the settings memory that the A2DP library allocated */
                    memory_free(settings);
                }
                
                /* update the state to reflect the media channel is connected */
                a2dp_set_state(inst, A2DP_STATE_CONNECTED_MEDIA);
            }
            else
            {
                /* if media can't be connected then disconnect signalling channel */
                a2dp_set_state(inst, A2DP_STATE_DISCONNECTING);
            }
        }
        break;
        
        default:
        {         
            a2dp_msg_unhandled_state(inst);
        }
        break;
    }      
}

2. 编译完成以后，连接蓝牙音箱测试codec类型，这里只是查看debug输出，实际可以添加LED指示，为了方便直观延时，通过切换了aptx和aptx-LL codec。

codec切换方法参考这篇教程：http://www.52bluetooth.com/portal.php?mod=view&aid=268

A2DP_INTERNAL_MEDIA_CLOSE_REQ:
        inst[0xe00]
A2DP_MEDIA_CLOSE_IND:
        inst[0xe00]
A2DP_INTERNAL_MEDIA_OPEN_REQ:
        inst[0xe00]
A2DP_MEDIA_OPEN_CFM 0:
        inst[0xe00]
  device ID:[0x0]
  stream ID [0x0]
  stream end point ID [0x3]
A2DP_INTERNAL_MEDIA_START_REQ:
        inst[0xe00]
A2DP_MEDIA_START_CFM 0:
        inst[0xe00]
A2DP_INTERNAL_MEDIA_CLOSE_REQ:
        inst[0xe00]
A2DP_MEDIA_CLOSE_IND:
        inst[0xe00]
A2DP_INTERNAL_MEDIA_OPEN_REQ:
        inst[0xe00]
A2DP_MEDIA_OPEN_CFM 0:
        inst[0xe00]
  device ID:[0x0]
  stream ID [0x0]
  stream end point ID [0x4]
A2DP_INTERNAL_MEDIA_START_REQ:
        inst[0xe00]
A2DP_MEDIA_START_CFM 0:
        inst[0xe00]

3. 根据debug输出的数字判断codec类型