(subset) [PATCH RFC 0/9] gpio: improve support for shared GPIOs

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bartosz.golaszewski at linaro.org>


On Wed, 24 Sep 2025 16:51:28 +0200, Bartosz Golaszewski wrote:
> Here's a functional RFC for improving the handling of shared GPIOs in
> linux.
> 
> Problem statement: GPIOs are implemented as a strictly exclusive
> resource in the kernel but there are lots of platforms on which single
> pin is shared by multiple devices which don't communicate so need some
> way of properly sharing access to a GPIO. What we have now is the
> GPIOD_FLAGS_BIT_NONEXCLUSIVE flag which was introduced as a hack and
> doesn't do any locking or arbitration of access - it literally just hand
> the same GPIO descriptor to all interested users.
> 
> [...]

I'm picking this one up for fixes as it addresses a locking bug.

[1/9] gpio: wcd934x: mark the GPIO controller as sleeping
      https://git.kernel.org/brgl/linux/c/83d314fac266a3d9de61e4a4490c4f2eafc86b05

Best regards,
-- 
Bartosz Golaszewski <bartosz.golaszewski at linaro.org>