media: uvcvideo: Ensure all probed info is returned to v4l2
authorAdam Goode <agoode@google.com>
Sun, 23 Aug 2020 01:21:33 +0000 (03:21 +0200)
committerMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Thu, 10 Sep 2020 12:06:27 +0000 (14:06 +0200)
commit8a652a17e3c005dcdae31b6c8fdf14382a29cbbe
treec0d91631de2316535f406af2503d3bf862188979
parent171994e498a0426cbe17f874c5c6af3c0af45200
media: uvcvideo: Ensure all probed info is returned to v4l2

bFrameIndex and bFormatIndex can be negotiated by the camera during
probing, resulting in the camera choosing a different format than
expected. v4l2 can already accommodate such changes, but the code was
not updating the proper fields.

Without such a change, v4l2 would potentially interpret the payload
incorrectly, causing corrupted output. This was happening on the
Elgato HD60 S+, which currently always renegotiates to format 1.

As an aside, the Elgato firmware is buggy and should not be renegotating,
but it is still a valid thing for the camera to do. Both macOS and Windows
will properly probe and read uncorrupted images from this camera.

With this change, both qv4l2 and chromium can now read uncorrupted video
from the Elgato HD60 S+.

[Add blank lines, remove periods at the of messages]

Signed-off-by: Adam Goode <agoode@google.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
drivers/media/usb/uvc/uvc_v4l2.c