From: Kirill A. Korinsky <kirill@korins.ky>
Subject: Re: sys/uvideo: support pre UVC 1.5 devices
To: Marcus Glocker <marcus@nazgul.ch>
Cc: tech@openbsd.org
Date: Sun, 10 Aug 2025 00:09:34 +0200

On Sat, 09 Aug 2025 22:11:21 +0200,
Marcus Glocker <marcus@nazgul.ch> wrote:
> 
> Since I didn't see the bug report myself;  Was this related to your
> previous commits for the further stream format support, or unrelated?
>  

1. User provided dmesg with debug log with:

uvideo0: could not GET probe request: SHORT_XFER

2. He suggested that he runs a hack since 7.3 by commentig a line with:

return (USBD_INVAL);

nearby this error line, and it fixed his webcam.

3. Linux has similar logic for old UVC devices, see:
https://github.com/torvalds/linux/blob/v6.16/drivers/media/usb/uvc/uvc_video.c#L345-L357

-- 
wbr, Kirill