[alsa-devel] Help with multichannel High Speed USB audio device

[Clemens Ladisch]

Laurent . wrote:
> I made an embedded device that has a CODEC with 6 inputs connected to an ARM9
> micro-controller that has an integrated high-speed USB controller.
> Now, I need to write the USB code on that micro-controller so that i can capture those
> channels in real-time at 24bits / 48 KHz with low latency (ie. sub 10ms), on a computer.
> 
> I only need my device to work with Linux, and if possible, I would like to avoid writing a device
> driver on the Linux-side.
> 
> Is there already such a USB audio driver available that I could nearly use "as is" and to which
> i would conform ?

Yes, snd-usb-audio.

> Would you have some general guideline on how to write the high-speed USB device code ?

Just conform to the USB (2.0) and USB Audio (1.0) specifications.

> For simplicity, my device is going to be the "clock master" of the system since it is already has
> the exact clock that drives the CODEC.

So you'd use an asynchronous endpoint.


Best regards,
Clemens