Support TC Helicon GoXLR

[Anthony Bourguignon]

Hi everyone,

I’m the owner of a GoXLR : https://www.tc-helicon.com/product.html?modelCode=P0CQK . It is a usb sound mixer that is not supported officially with
Linux. The main issue is that the GoXLR is a multi inputs / multi outputs device, but it is not seen as one. It works great under Windows thanks to a
driver. With Linux, it is seen as a single usb sound device with a single multichannel output. Right now, I managed with other people to separate
those channels with pulseaudio or jack or even pipewire. For exemple, Front Left and Front Right are the stereo output named "System". Rear left and
rear right are another stereo output name Game. There are other outputs, and it is the same mechanism for the inputs.

But I’ve seen that a few usb devices do have quirks for them to behave as expected, without the need of configuration with pulse or pipewire. But from
what I understand, it’s only to disable subdevices or reorder outputs. Am I wrong ? Is it possible to add a quirk for a device like the GoXLR and
change the multichannel output into multiple subdevices with alsa ?

Thanks a lot if you can help me and the others owners.

Anthony