Commit 8c426941 authored Jun 18, 2021 by Ricardo Ribalda Committed by Mauro Carvalho Chehab Sep 30, 2021

media: docs: Document the behaviour of uvcvideo driver



The uvc driver relies on the camera firmware to keep the control states
and therefore is not capable of changing an inactive control.

Allow returning -EACCES in those cases.

Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

parent 6350d6a4

Documentation/userspace-api/media/v4l/vidioc-g-ctrl.rst

+3 −0

Original line number	Diff line number	Diff line
		@@ -95,3 +95,6 @@ EBUSY

		EACCES
		Attempt to set a read-only control or to get a write-only control.

		Or if there is an attempt to set an inactive control and the driver is
		not capable of caching the new value until the control is active again.

Documentation/userspace-api/media/v4l/vidioc-g-ext-ctrls.rst

+3 −0

Original line number	Diff line number	Diff line
		@@ -470,3 +470,6 @@ EACCES

		Or the ``which`` field was set to ``V4L2_CTRL_WHICH_REQUEST_VAL`` but the
		device does not support requests.

		Or if there is an attempt to set an inactive control and the driver is
		not capable of caching the new value until the control is active again.