Re: [PATCH v3 1/1] media: uvcvideo: require entities to have a non-zero unique ID

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

On Wed, Jan 08, 2025 at 12:32:07PM -0300, Thadeu Lima de Souza Cascardo wrote:
> On Mon, Jan 06, 2025 at 02:15:24PM +0100, Tomasz Sikora wrote:
> > Error in line 1034 dmesg.log
> > You can see more here https://bbs.archlinux.org/viewtopic.php?id=301737
> > 
> > pon., 6 sty 2025 o 11:56 Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
> > napisał(a):
> > 
> > > On Sun, Jan 05, 2025 at 07:31:09PM +0100, Tomasz Sikora wrote:
> > > > Issue video camera
> > > > ls -l /dev/video*zsh: no matches found: /dev/video*
> > > >
> > > >
> > > > 01 15:43:24 Linux kernel: usb 3-2: Found multiple Units with ID 5
> > >
> > > Can you attach complete dmesg output? And more importantly, attach the
> > > output of lsusb -vv?
> > >
> > > Thanks.
> > > Cascardo.
> > >
> 
> Thanks a lot, Tomasz.
> 
> Without this patch (it could be an older kernel), do you see a warning in
> your dmesg? Or messages like:
> 
> [  395.090938] usb 1-1: Failed to create links for entity 5
> [  395.091385] usb 1-1: Failed to register entities (-22).
> 
> Otherwise, it might just be that your kernel is not built with
> CONFIG_MEDIA_CONTROLLER.
> 
> I reached that conclusion by emulating a similar uvc device. Yours has the
> entity ID for both the output terminal and processing unit. Though that is
> not valid according to the spec (even UVC 1.0 mentions the IDs should be
> unique), we should keep supporting such devices.
> 
> I am currently working on a fix that will restore support for your device
> but improve its support for configs with CONFIG_MEDIA_CONTROLLER.
> 
> I appreciate your help on testing such configurations and fixes.

The output of "lsusb -v -d 1c3f:2002" would help (running as root if
possible).

-- 
Regards,

Laurent Pinchart