7291d99ebc
[ Upstream commit b3168c87c0492661badc3e908f977d79e7738a41 ]
Because the brightness and contrast controls share a register,
usbtv_s_ctrl needs to read the existing values for both controls before
inserting the new value. However, the code accidentally wrote to the
registers (from an uninitialised stack array), rather than reading them.
The user-visible effect of this was that adjusting the brightness would
also set the contrast to a random value, and vice versa -- so it wasn't
possible to correctly adjust the brightness of usbtv's video output.
Tested with an "EasyDAY" UTV007 device.
Fixes: c53a846c48f2 ("usbtv: add video controls")
Signed-off-by: Adam Sampson <ats@offog.org>
Reviewed-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.