USB Gadget audio not working

USB Gadget audio not working

[noman pouigt]

Hello,

I am trying to use my device as a sound card and enabled
CONFIG_USB_AUDIO. However I don't know what kind
of device node should be added in the machine file?

I just want to record whatever is coming into the USB played
back by the host over USB.

I could get my device to be detected as a sound card i.e.
USB_AUDIO_CLASS in my ubuntu machine.

My understanding of USB audio is very less so I thought
below change should be sufficient.

Below are the only changes which i have done to enable USB_AUDIO.

Machine file:
{
.name = "something_random",
.stream_name = "USB Capture",
.cpu_dai_name = "snd-soc-dummy-dai",
.codec_dai_name = "snd-soc-dummy-dai",
.codec_name = "snd-soc-dummy",
.ignore_suspend = 1,
},

drivers/usb/gadget/u_uac1.c :
#define FILE_PCM_PLAYBACK "/dev/snd/pcmC0D0p"
#define FILE_PCM_CAPTURE "/dev/snd/pcmC0D0c"

in defconfig
CONFIG_USB_AUDIO=y

Please let me know if I am doing anything wrong.

Thanks,

Re: USB Gadget audio not working

[Clemens Ladisch]

noman pouigt wrote:
> I am trying to use my device as a sound card and enabled
> CONFIG_USB_AUDIO.

That configuration is for the host driver, not for the gadget driver.

> I could get my device to be detected as a sound card

Then you have correctly enabled CONFIG_USB_F_UAC1.

> However I don't know what kind
> of device node should be added in the machine file?

As far as I can see, none.
See Documentation/usb/gadget-testing.txt.


Regards,
Clemens