Re: [linux-uvc-devel] Cannot use webcam under Linux but works under windows

[Lucas M. <luc...@gm...>]

Hi Pierre,

On Thu, 2018-01-25 at 15:17 +0100, Pierre Daye wrote:
> [  157.573136] uvcvideo: Failed to query (GET_DEF) UVC control 13 on
> unit 1: -32 (exp. 8).

These UVC GET_DEF errors could be causing a problem. Does your camera
come with a uvcdynctrl xml file or datasheet that details the supported
UVC extension units? The returned size appears to be wrong.

Also, try the UVC_QUIRK_PROBE_DEF (0x00000100) quirk and see if that
helps.

>From http://www.ideasonboard.org/uvc/faq/ : 

UVC_QUIRK_PROBE_DEF: Don't request the video probe and commit default
values. Some cameras don't implement the GET_DEF request for the video
probe and commit controls, or even completely crash when that request
is received. The uvcvideo driver can then use the current values as
default values.