I upgraded kernel to 5.0 rc1 and the error message  "Unknown
pixelformat 0x00000000" are disappeared.

Instead I see not obvious message "uvcvideo: Non-zero status (-71) in
video completion handler."
Maybe in this case better to write "Video format XXX not supported" ?
It would help quickly understand that is culprit here.


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Best Regards,
Mike Gavrilov.