Re: [PATCH v1 1/1] pinctrl: intel: Fix a glitch when updating IRQ flags on a preconfigured line

From: Andy Shevchenko
Date: Mon Jan 24 2022 - 08:38:10 EST


On Thu, Jan 20, 2022 at 09:44:52AM +0200, Mika Westerberg wrote:
> On Wed, Jan 19, 2022 at 08:19:15PM +0200, Andy Shevchenko wrote:
> > The commit af7e3eeb84e2 ("pinctrl: intel: Disable input and output buffer
> > when switching to GPIO") hadn't taken into account an update of the IRQ
> > flags scenario.
> >
> > When updating the IRQ flags on the preconfigured line the ->irq_set_type()
> > is called again. In such case the sequential Rx buffer configuration
> > changes may trigger a falling or rising edge interrupt that may lead,
> > on some platforms, to an undesired event.
> >
> > This may happen because each of intel_gpio_set_gpio_mode() and
> > __intel_gpio_set_direction() updates the pad configuration with a different
> > value of the GPIORXDIS bit. Notable, that the intel_gpio_set_gpio_mode() is
> > called only for the pads that are configured as an input. Due to this fact,
> > integrate the logic of __intel_gpio_set_direction() call into the
> > intel_gpio_set_gpio_mode() so that the Rx buffer won't be disabled and
> > immediately re-enabled.
> >
> > Fixes: af7e3eeb84e2 ("pinctrl: intel: Disable input and output buffer when switching to GPIO")
> > Reported-by: Kane Chen <kane.chen@xxxxxxxxx>
> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
>
> Acked-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
>
> Please mark this for stable too.

Pushed to my review and testing queue with the Grace Kao's tag, thanks!

--
With Best Regards,
Andy Shevchenko