On Thu Jul 23, 2026 at 5:42 AM CEST, Yu-Chun Lin wrote:
> Add a new set_config callback to allow drivers to implement
> hardware-specific configuration such as debounce settings, or other
> platform-specific GPIO properties.
>
> Signed-off-by: Yu-Chun Lin <eleanor.lin@realtek.com>
> ---
> Changes in v7:
> - Drop the reviewed by tag from Andy due to the signature changes.
> - Add 'struct gpio_regmap' as the first parameter to the set_config callback.
> - Add wrapper to bridge gpio_chip to gpio_regmap.
> ---
>  drivers/gpio/gpio-regmap.c  | 16 ++++++++++++++++
>  include/linux/gpio/regmap.h |  6 ++++++
>  2 files changed, 22 insertions(+)
>
> diff --git a/drivers/gpio/gpio-regmap.c b/drivers/gpio/gpio-regmap.c
> index 8f58b272b870..98cfdd890069 100644
> --- a/drivers/gpio/gpio-regmap.c
> +++ b/drivers/gpio/gpio-regmap.c
> @@ -51,6 +51,9 @@ struct gpio_regmap {
>  			   unsigned int reg, unsigned int *mask,
>  			   unsigned int *val);
>  
> +	int (*set_config)(struct gpio_regmap *gpio, struct gpio_chip *chip,
> +			  unsigned int offset, unsigned long config);
> +
>  	void *driver_data;
>  };
>  
> @@ -317,6 +320,15 @@ static int gpio_regmap_direction_output(struct gpio_chip *chip,
>  	return gpio_regmap_set_direction(chip, offset, true);
>  }
>  
> +static int gpio_regmap_set_config(struct gpio_chip *chip,
> +				  unsigned int offset,
> +				  unsigned long cfg)
> +{
> +	struct gpio_regmap *gpio = gpiochip_get_data(chip);
> +
> +	return gpio->set_config(gpio, chip, offset, cfg);
> +}
> +
>  int gpio_regmap_reqres_irq(struct gpio_regmap *gpio, unsigned int offset)
>  {
>  	return gpiochip_reqres_irq(&gpio->gpio_chip, offset);
> @@ -386,6 +398,7 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config
>  	gpio->reg_clr_base = config->reg_clr_base;
>  	gpio->reg_dir_in_base = config->reg_dir_in_base;
>  	gpio->reg_dir_out_base = config->reg_dir_out_base;
> +	gpio->set_config = config->set_config;
>  
>  	chip = &gpio->gpio_chip;
>  	chip->parent = config->parent;
> @@ -455,6 +468,9 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config
>  
>  	gpio->value_xlate = config->value_xlate;
>  
> +	if (config->set_config)
> +		chip->set_config = gpio_regmap_set_config;
> +

Please keep both settings together. i.e.

if (config->set_config) {
	gpio->set_config = config->set_config;
	chip->set_config = gpio_regmap_set_config;
}

With that fixed:
Reviewed-by: Michael Walle <mwalle@kernel.org>

-michael

>  	ret = gpiochip_add_data(chip, gpio);
>  	if (ret < 0)
>  		goto err_free_bitmap_output;
> diff --git a/include/linux/gpio/regmap.h b/include/linux/gpio/regmap.h
> index b77d6371cd9c..4bf4319ec12e 100644
> --- a/include/linux/gpio/regmap.h
> +++ b/include/linux/gpio/regmap.h
> @@ -93,6 +93,9 @@ enum gpio_regmap_operation {
>   *			mask before writing. This allows driver-specific logic
>   *			to append additional bits (like write-enable masks)
>   *			dynamically based on the current operation.
> + * @set_config:		(Optional) Callback for setting GPIO configuration such
> + *			as debounce, drive strength, or other hardware specific
> + *			settings.
>   * @drvdata:		(Optional) Pointer to driver specific data which is
>   *			not used by gpio-remap but is provided "as is" to the
>   *			driver callback(s).
> @@ -154,6 +157,9 @@ struct gpio_regmap_config {
>  			   unsigned int base, unsigned int offset, unsigned int reg,
>  			   unsigned int *mask, unsigned int *val);
>  
> +	int (*set_config)(struct gpio_regmap *gpio, struct gpio_chip *chip,
> +			  unsigned int offset, unsigned long config);
> +
>  	void *drvdata;
>  };
>