hello,
my device works fine with 16bit, 2channel, 48KHz descriptor.
Now, I want to implement 24bit ,2channel ,48Khz descriptor. I only change
audio streaming format type as below:
//TYPE 1 Format type descriptor
CONFIG_FORMAT_TYPE_SIZE,
bDescriptorType_CS_INTERFACE, //bDescriptorType: CS_INTERFACE,
bInterfaceSubClass_AS_FORMAT_TYPE, //format type
eAudioDataFormat_Type1, //Type I
2, //NrChannels
0x03, //bSubFrameSize
24, //bBitresolutions
0x01, //one freq
0x80,0xBB,0x00, // 48KHz
after descriptor changed, windows can recognize audio device, but audio data format
is still 16 bit,not 24bit!!!
USB speaker Topology:
usb streaming IT --> Feature Control --> USB streaming OT -->Speaker
Audio streaming data flow:
windows recognize usb audio device as speaker, windows media player send audio streaming
data to usb audio speaker. USB speaker receives audio data streaming through endpoint4. then
usb speaker device process the audio streaming data as I2S format output.
if anybody have 24/32 bit audio experience, Please help me on this.