Re: [PATCH v1 1/1] gpiolib: acpi: Convert ACPI value of debounce to microseconds

[Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>]

On Mon, Mar 7, 2022 at 7:56 PM Andy Shevchenko
<andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
>
> It appears that GPIO ACPI library uses ACPI debounce values directly.
> However, the GPIO library APIs expect the debounce timeout to be in
> microseconds.
>
> Convert ACPI value of debounce to microseconds.
>
> While at it, document this detail where it is appropriate.
>
> BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=215664
> Reported-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
> Fixes: 8dcb7a15a585 ("gpiolib: acpi: Take into account debounce settings")
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

This works for me. Thanks!

Tested-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>

> ---
>  drivers/gpio/gpiolib-acpi.c |  6 ++++--
>  drivers/gpio/gpiolib.c      | 10 ++++++++++
>  2 files changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
> index c0f6a25c3279..a5495ad31c9c 100644
> --- a/drivers/gpio/gpiolib-acpi.c
> +++ b/drivers/gpio/gpiolib-acpi.c
> @@ -307,7 +307,8 @@ static struct gpio_desc *acpi_request_own_gpiod(struct gpio_chip *chip,
>         if (IS_ERR(desc))
>                 return desc;
>
> -       ret = gpio_set_debounce_timeout(desc, agpio->debounce_timeout);
> +       /* ACPI uses hundredths of milliseconds units */
> +       ret = gpio_set_debounce_timeout(desc, agpio->debounce_timeout * 10);
>         if (ret)
>                 dev_warn(chip->parent,
>                          "Failed to set debounce-timeout for pin 0x%04X, err %d\n",
> @@ -1035,7 +1036,8 @@ int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name, int ind
>                         if (ret < 0)
>                                 return ret;
>
> -                       ret = gpio_set_debounce_timeout(desc, info.debounce);
> +                       /* ACPI uses hundredths of milliseconds units */
> +                       ret = gpio_set_debounce_timeout(desc, info.debounce * 10);
>                         if (ret)
>                                 return ret;
>
> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index f5e7443208d4..f956c533f218 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -2223,6 +2223,16 @@ static int gpio_set_bias(struct gpio_desc *desc)
>         return gpio_set_config_with_argument_optional(desc, bias, arg);
>  }
>
> +/**
> + * gpio_set_debounce_timeout() - Set debounce timeout
> + * @desc:      GPIO descriptor to set the debounce timeout
> + * @debounce:  Debounce timeout in microseconds
> + *
> + * The function calls the certain GPIO driver to set debounce timeout
> + * in the hardware.
> + *
> + * Returns 0 on success, or negative error code otherwise.
> + */
>  int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce)
>  {
>         return gpio_set_config_with_argument_optional(desc,
> --
> 2.34.1
>