Re: [PATCH regression fix] gpiolib: acpi: Make set-debounce-timeout failures non fatal

[Mika Westerberg <mika.westerberg@linux.intel.com>]

On Mon, Aug 16, 2021 at 11:38:56AM +0200, Hans de Goede wrote:
> Commit 8dcb7a15a585 ("gpiolib: acpi: Take into account debounce settings")
> made the gpiolib-acpi code call gpio_set_debounce_timeout() when requesting
> GPIOs.
> 
> This in itself is fine, but it also made gpio_set_debounce_timeout()
> errors fatal, causing the requesting of the GPIO to fail. This is causing
> regressions. E.g. on a HP ElitePad 1000 G2 various _AEI specified GPIO
> ACPI event sources specify a debouncy timeout of 20 ms, but the
> pinctrl-baytrail.c only supports certain fixed values, the closest
> ones being 12 or 14 ms and pinctrl-baytrail.c responds with -EINVAL
> when specified a value which is not one of the fixed values.
> 
> This is causing the acpi_request_own_gpiod() call to fail for 3
> ACPI event sources on the HP ElitePad 1000 G2, which in turn is causing
> e.g. the battery charging vs discharging status to never get updated,
> even though a charger has been plugged-in or unplugged.
> 
> Make gpio_set_debounce_timeout() errors non fatal, warning about the
> failure instead, to fix this regression.
> 
> Note we should probably also fix various pinctrl drivers to just
> pick the first bigger discrete value rather then returning -EINVAL but
> this will need to be done on a per driver basis, where as this fix
> at least gets us back to where things were before and thus restores
> functionality on devices where this was lost due to
> gpio_set_debounce_timeout() errors.
> 
> Fixes: 8dcb7a15a585 ("gpiolib: acpi: Take into account debounce settings")
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>