On Sat, Aug 31, 2019 at 11:09:14AM +0800, Peter Cai wrote:
> On GPD P2 Max, the firmware could not reset the touch panel correctly.
> The kernel needs to take on the job instead, but the GpioInt definition
> in DSDT specifies ActiveHigh while the GPIO pin should actually be
> ActiveLow.
>
> We need to override the polarity defined by DSDT. The GPIO driver
> already allows defining polarity in acpi_gpio_params, but the option is
> not applied to GpioInt.
>
> This patch adds a new quirk that enables the polarity specified in
> acpi_gpio_params to also be applied to GpioInt.
Thank you for an update!
Acked-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
on the condition that Dmitry and other input / Goodix developers are okay with
the approach in general.
>
> Signed-off-by: Peter Cai <peter@xxxxxxxxxxxx>
> ---
>
> v2: rebased to gpio/for-next, moved quirk out of the gpioint
> conditional.
> ---
> drivers/gpio/gpiolib-acpi.c | 9 +++++++++
> include/linux/gpio/consumer.h | 6 ++++++
> 2 files changed, 15 insertions(+)
>
> diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
> index fdee8afa5339..ab16ea61a8fa 100644
> --- a/drivers/gpio/gpiolib-acpi.c
> +++ b/drivers/gpio/gpiolib-acpi.c
> @@ -603,6 +603,15 @@ static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
> lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio);
> lookup->info.polarity = lookup->active_low;
> }
> +
> + /*
> + * Override the polarity specified by GpioInt if
> + * ACPI_GPIO_QUIRK_OVERRIDE_POLARITY is set.
> + */
> + if (lookup->info.quirks & ACPI_GPIO_QUIRK_OVERRIDE_POLARITY) {
> + dev_warn(&lookup->info.adev->dev, FW_BUG "Incorrect polarity specified by GpioInt, overriding.\n");
> + lookup->info.polarity = lookup->active_low;
> + }
> }
>
> return 1;
> diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h
> index b70af921c614..7e9f24ebb085 100644
> --- a/include/linux/gpio/consumer.h
> +++ b/include/linux/gpio/consumer.h
> @@ -622,6 +622,12 @@ struct acpi_gpio_mapping {
> * get GpioIo type explicitly, this quirk may be used.
> */
> #define ACPI_GPIO_QUIRK_ONLY_GPIOIO BIT(1)
> +/*
> + * Use the GPIO polarity (ActiveHigh / ActiveLow) from acpi_gpio_params
> + * for GpioInt as well. The default behavior is to use the one specified
> + * by GpioInt, which can be incorrect on some devices.
> + */
> +#define ACPI_GPIO_QUIRK_OVERRIDE_POLARITY BIT(2)
>
> unsigned int quirks;
> };
> --
> 2.23.0
>
--
With Best Regards,
Andy Shevchenko
