On Tue, Jun 8, 2021 at 3:44 AM Roman Muller klangrausch@wolke7.net wrote:
Hello Geraldo, hello all,
sorry for spamming the list with such minuscule details.
Hi Roman, don't worry, your message is on topic...
Thank you for your message! I did not hear from other people yet, so it's probably safe to assume that no one else is already working on it. Adding a section to the quirks-table does not help, the vendor-specific interfaces still don't work. Obviously they need extra initialization.
Next step: sniffing again while running Windows in the vm. The interesting stuff is going on here: https://drive.google.com/file/d/1IlkR4ey9Gwsdrrf6jfOwNUVDtGcl_93- (Full log: https://drive.google.com/file/d/1VmSGVk8V1saw7qdPfbOH2d4HmZTrlzxj)
From this I see several URB control messages going back and forth, for example the host sending 80bbf0, and the device responding accordingly. A bit later, and after sending 44ac00 six times (hola!?!?) I get isodesc[0-7] cross-device link for input; and once more for output, and the device reports success. These appear to be my eight channels. So far, so good for a first basic overview of the structure, but the tricky part is figuring out what message is doing what.
Your Xone:43C doesn't seem so esoteric from the usbmon capture you gave.
Is your capture complete from a software standpoint? i.e. are you starting Serato or Traktor on the VM while doing the usbmon capture?
80bbf0 is just the data fragment, you need to replicate the whole Setup Data of the packet.
Only the manufacturer knows it, I need experiment and guessing with a lot of time and luck.
You probably don't really need to know for now what these control messages are. There's a good chance replicating them is enough.
Is there a common agreement where in the source code such control messages should be put? Probably an extra file?
I think you should worry for now in getting your device to work. Then you share the patch with the maintainers and they will help you write the best code possible.
But sound/usb/quirks.c seems like a good place to get started.
All the best, Geraldo Nascimento
Best, Roman