Re: uvideo

[Michael van Elst <mlelstv%serpens.de@localhost>]

On Sun, Apr 13, 2025 at 06:10:16PM +0100, Patrick Welche wrote:
> On Sat, Apr 12, 2025 at 08:25:49PM -0000, Michael van Elst wrote:
> > Build a kernel with option UVIDEO_DEBUG, this might give some hint about the error.
> 
> Right!
> 
> # videoctl -d /dev/video0 -a
> videoctl: couldn't open '/dev/video0': Input/output error
> 
> videoopen
> videoopen: flags=0x1 sc=0xffff81a57e505c40 parent=0xffff81a57e4e15c0
> uvideo_open: sc=0xffff81a57e4eac40
> uvideo_set_format: sc=0xffff81a57e4eac40
> uvideo: error probe/GET_MAX: STALLED (17)

The device doesn't return a maximum quality value.


> uvideo: error commit/SET_CUR: STALLED (17)

The device doesn't let you set a probe format, and that
aborts the open operation with EIO.


Looks like uvideo needs to get smarter to handle that device.



> and usbdevs just shows
> 
>  port 6 addr 2: high speed, power 500 mA, config 1, Integrated_Webcam_HD(0x5531), CKFIH12P466071019182(0x0bda), rev 81.78(0x8178), serial 200901010001
>    uvideo0
>    uvideo1
> 
> no sign of uvideo2 and 3.

One device, two interfaces attach a uvideo instance, and each uvideo
instance attaches two streams (video0/1 and video2/3).


Greetings,
-- 
                                Michael van Elst
Internet: mlelstv%serpens.de@localhost
                                "A potential Snark may lurk in every tree."