0f482ad7b1
[ Upstream commit c8befdc411e5fd1bf95a13e8744c8ca79b412bee ]
The Qualcomm LPASS LPI pin controller driver uses one lock for guarding
Read-Modify-Write code for slew rate registers. However the pin
configuration and muxing registers have exactly the same RMW code but
are not protected.
Pin controller framework does not provide locking here, thus it is
possible to trigger simultaneous change of pin configuration registers
resulting in non-atomic changes.
Protect from concurrent access by re-using the same lock used to cover
the slew rate register. Using the same lock instead of adding second
one will make more sense, once we add support for newer Qualcomm SoC,
where slew rate is configured in the same register as pin
configuration/muxing.
Fixes: 6e261d1090d6 ("pinctrl: qcom: Add sm8250 lpass lpi pinctrl driver")
Cc: stable@vger.kernel.org
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20231013145705.219954-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
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.