Re: [PATCH v6 5/8] gpio: regmap: Add gpio_regmap_operation and value_xlate support

[Jonathan Cameron <jic23@kernel.org>]

On Tue, 21 Jul 2026 14:57:59 +0800
Yu-Chun Lin <eleanor.lin@realtek.com> wrote:

> Extend the reg_mask_xlate callback with an operation type parameter
> (enum gpio_regmap_operation) to allow drivers to return different
> register/mask combinations depending on the specific GPIO operation.
> 
> In addition, introduce a new optional 'value_xlate' callback. This routine
> allows drivers to translate or modify the register value and mask
> immediately before a write operation. It is particularly useful for
> hardware that requires additional control bits, such as a write-enable bit,
> to be appended to the data dynamically.
> 
> Consequently, update all existing drivers utilizing the gpio-regmap
> framework (across drivers/gpio, drivers/iio, and drivers/pinctrl)
> to accommodate the new reg_mask_xlate function signature.
> 
> Suggested-by: Linus Walleij <linusw@kernel.org>
> Signed-off-by: Yu-Chun Lin <eleanor.lin@realtek.com>
Acked-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com> #for-iio
> ---
> Changes in v6:
> - Remove removed the hardcoded write-enable workarounds.
> - Retain the necessary prototype updates in every driver using custom
> reg_mask_xlate
> - Add value_xlate to dynamically adjust the register mask and value right
> before the actual register write operation.
> ---
>  drivers/gpio/gpio-104-idi-48.c        |  7 +--
>  drivers/gpio/gpio-i8255.c             |  4 +-
>  drivers/gpio/gpio-idio-16.c           |  6 +--
>  drivers/gpio/gpio-max7360.c           |  1 +
>  drivers/gpio/gpio-pcie-idio-24.c      |  6 +--
>  drivers/gpio/gpio-regmap.c            | 62 ++++++++++++++++++++++-----
>  drivers/iio/adc/ad7173.c              |  8 ++--
>  drivers/iio/addac/stx104.c            |  6 +--
>  drivers/pinctrl/bcm/pinctrl-bcm63xx.c |  1 +
>  drivers/pinctrl/pinctrl-tps6594.c     |  1 +
>  include/linux/gpio/regmap.h           | 44 +++++++++++++++++--
>  11 files changed, 115 insertions(+), 31 deletions(-)
> 
> diff --git a/drivers/gpio/gpio-104-idi-48.c b/drivers/gpio/gpio-104-idi-48.c
> index ba73ee9c0c29..fb017569cfa8 100644
> --- a/drivers/gpio/gpio-104-idi-48.c
> +++ b/drivers/gpio/gpio-104-idi-48.c
> @@ -36,9 +36,10 @@ MODULE_PARM_DESC(irq, "ACCES 104-IDI-48 interrupt line numbers");
>  #define IDI48_IRQ_STATUS 0x7
>  #define IDI48_IRQ_ENABLE IDI48_IRQ_STATUS
>  
> -static int idi_48_reg_mask_xlate(struct gpio_regmap *gpio, unsigned int base,
> -				 unsigned int offset, unsigned int *reg,
> -				 unsigned int *mask)
> +static int idi_48_reg_mask_xlate(struct gpio_regmap *gpio,
> +				 enum gpio_regmap_operation op,
> +				 unsigned int base, unsigned int offset,
> +				 unsigned int *reg, unsigned int *mask)
>  {
>  	const unsigned int line = offset % 8;
>  	const unsigned int stride = offset / 8;
> diff --git a/drivers/gpio/gpio-i8255.c b/drivers/gpio/gpio-i8255.c
> index 953018bfa2b1..541a348447cd 100644
> --- a/drivers/gpio/gpio-i8255.c
> +++ b/drivers/gpio/gpio-i8255.c
> @@ -67,8 +67,8 @@ static int i8255_ppi_init(struct regmap *const map, const unsigned int base)
>  	return regmap_write(map, base + I8255_PORTC, 0x00);
>  }
>  
> -static int i8255_reg_mask_xlate(struct gpio_regmap *gpio, unsigned int base,
> -				unsigned int offset, unsigned int *reg,
> +static int i8255_reg_mask_xlate(struct gpio_regmap *gpio, enum gpio_regmap_operation op,
> +				unsigned int base, unsigned int offset, unsigned int *reg,
>  				unsigned int *mask)
>  {
>  	const unsigned int ppi = offset / I8255_NGPIO;
> diff --git a/drivers/gpio/gpio-idio-16.c b/drivers/gpio/gpio-idio-16.c
> index 4fbae6f6a497..9ac967c6b430 100644
> --- a/drivers/gpio/gpio-idio-16.c
> +++ b/drivers/gpio/gpio-idio-16.c
> @@ -66,9 +66,9 @@ static int idio_16_handle_mask_sync(const int index, const unsigned int mask_buf
>  	return 0;
>  }
>  
> -static int idio_16_reg_mask_xlate(struct gpio_regmap *const gpio, const unsigned int base,
> -				  const unsigned int offset, unsigned int *const reg,
> -				  unsigned int *const mask)
> +static int idio_16_reg_mask_xlate(struct gpio_regmap *const gpio, enum gpio_regmap_operation op,
> +				  const unsigned int base, const unsigned int offset,
> +				  unsigned int *const reg, unsigned int *const mask)
>  {
>  	unsigned int stride;
>  
> diff --git a/drivers/gpio/gpio-max7360.c b/drivers/gpio/gpio-max7360.c
> index 07eda49f375b..6755d58c4534 100644
> --- a/drivers/gpio/gpio-max7360.c
> +++ b/drivers/gpio/gpio-max7360.c
> @@ -93,6 +93,7 @@ static int max7360_set_gpos_count(struct device *dev, struct regmap *regmap)
>  }
>  
>  static int max7360_gpio_reg_mask_xlate(struct gpio_regmap *gpio,
> +				       enum gpio_regmap_operation op,
>  				       unsigned int base, unsigned int offset,
>  				       unsigned int *reg, unsigned int *mask)
>  {
> diff --git a/drivers/gpio/gpio-pcie-idio-24.c b/drivers/gpio/gpio-pcie-idio-24.c
> index 80c0ba0afa67..b99f4863443d 100644
> --- a/drivers/gpio/gpio-pcie-idio-24.c
> +++ b/drivers/gpio/gpio-pcie-idio-24.c
> @@ -225,9 +225,9 @@ static int idio_24_set_type_config(unsigned int **const buf, const unsigned int
>  	return ret;
>  }
>  
> -static int idio_24_reg_mask_xlate(struct gpio_regmap *const gpio, const unsigned int base,
> -				  const unsigned int offset, unsigned int *const reg,
> -				  unsigned int *const mask)
> +static int idio_24_reg_mask_xlate(struct gpio_regmap *const gpio, enum gpio_regmap_operation op,
> +				  const unsigned int base, const unsigned int offset,
> +				  unsigned int *const reg, unsigned int *const mask)
>  {
>  	const unsigned int out_stride = offset / IDIO_24_NGPIO_PER_REG;
>  	const unsigned int in_stride = (offset - 24) / IDIO_24_NGPIO_PER_REG;
> diff --git a/drivers/gpio/gpio-regmap.c b/drivers/gpio/gpio-regmap.c
> index 658b892b624c..aecc35f610dd 100644
> --- a/drivers/gpio/gpio-regmap.c
> +++ b/drivers/gpio/gpio-regmap.c
> @@ -40,9 +40,16 @@ struct gpio_regmap {
>  	struct regmap_irq_chip_data *irq_chip_data;
>  #endif
>  
> -	int (*reg_mask_xlate)(struct gpio_regmap *gpio, unsigned int base,
> -			      unsigned int offset, unsigned int *reg,
> -			      unsigned int *mask);
> +	int (*reg_mask_xlate)(struct gpio_regmap *gpio,
> +			      enum gpio_regmap_operation op,
> +			      unsigned int base, unsigned int offset,
> +			      unsigned int *reg, unsigned int *mask);
> +
> +	int (*value_xlate)(struct gpio_regmap *gpio,
> +			   enum gpio_regmap_operation op,
> +			   unsigned int base, unsigned int offset,
> +			   unsigned int reg, unsigned int *mask,
> +			   unsigned int *val);
>  
>  	void *driver_data;
>  };
> @@ -56,6 +63,7 @@ static unsigned int gpio_regmap_addr(unsigned int addr)
>  }
>  
>  static int gpio_regmap_simple_xlate(struct gpio_regmap *gpio,
> +				    enum gpio_regmap_operation op,
>  				    unsigned int base, unsigned int offset,
>  				    unsigned int *reg, unsigned int *mask)
>  {
> @@ -71,7 +79,7 @@ static int gpio_regmap_simple_xlate(struct gpio_regmap *gpio,
>  static int gpio_regmap_get(struct gpio_chip *chip, unsigned int offset)
>  {
>  	struct gpio_regmap *gpio = gpiochip_get_data(chip);
> -	unsigned int base, val, reg, mask;
> +	unsigned int base, val, reg, mask, dir_mask;
>  	int ret;
>  
>  	/* we might not have an output register if we are input only */
> @@ -80,7 +88,18 @@ static int gpio_regmap_get(struct gpio_chip *chip, unsigned int offset)
>  	else
>  		base = gpio_regmap_addr(gpio->reg_set_base);
>  
> -	ret = gpio->reg_mask_xlate(gpio, base, offset, &reg, &mask);
> +	ret = gpio->reg_mask_xlate(gpio, GPIO_REGMAP_GET_OP, base, offset, &reg, &dir_mask);
> +	if (ret)
> +		return ret;
> +
> +	ret = regmap_read(gpio->regmap, reg, &val);
> +	if (ret)
> +		return ret;
> +
> +	if (val & dir_mask)
> +		ret = gpio->reg_mask_xlate(gpio, GPIO_REGMAP_OUT, base, offset, &reg, &mask);
> +	else
> +		ret = gpio->reg_mask_xlate(gpio, GPIO_REGMAP_IN, base, offset, &reg, &mask);
>  	if (ret)
>  		return ret;
>  
> @@ -103,7 +122,7 @@ static int gpio_regmap_set(struct gpio_chip *chip, unsigned int offset,
>  	unsigned int reg, mask, mask_val;
>  	int ret;
>  
> -	ret = gpio->reg_mask_xlate(gpio, base, offset, &reg, &mask);
> +	ret = gpio->reg_mask_xlate(gpio, GPIO_REGMAP_SET_OP, base, offset, &reg, &mask);
>  	if (ret)
>  		return ret;
>  
> @@ -112,6 +131,13 @@ static int gpio_regmap_set(struct gpio_chip *chip, unsigned int offset,
>  	else
>  		mask_val = 0;
>  
> +	if (gpio->value_xlate) {
> +		ret = gpio->value_xlate(gpio, GPIO_REGMAP_SET_OP, base, offset,
> +					reg, &mask, &mask_val);
> +		if (ret)
> +			return ret;
> +	}
> +
>  	/* ignore input values which shadow the old output value */
>  	if (gpio->reg_dat_base == gpio->reg_set_base)
>  		ret = regmap_write_bits(gpio->regmap, reg, mask, mask_val);
> @@ -125,7 +151,7 @@ static int gpio_regmap_set_with_clear(struct gpio_chip *chip,
>  				      unsigned int offset, int val)
>  {
>  	struct gpio_regmap *gpio = gpiochip_get_data(chip);
> -	unsigned int base, reg, mask;
> +	unsigned int base, reg, mask, value = 0;
>  	int ret;
>  
>  	if (val)
> @@ -133,10 +159,17 @@ static int gpio_regmap_set_with_clear(struct gpio_chip *chip,
>  	else
>  		base = gpio_regmap_addr(gpio->reg_clr_base);
>  
> -	ret = gpio->reg_mask_xlate(gpio, base, offset, &reg, &mask);
> +	ret = gpio->reg_mask_xlate(gpio, GPIO_REGMAP_SET_OP, base, offset, &reg, &mask);
>  	if (ret)
>  		return ret;
>  
> +	if (gpio->value_xlate) {
> +		ret = gpio->value_xlate(gpio, GPIO_REGMAP_SET_OP, base, offset,
> +					reg, &mask, &value);
> +		if (ret)
> +			return ret;
> +	}
> +
>  	return regmap_write(gpio->regmap, reg, mask);
>  }
>  
> @@ -183,7 +216,7 @@ static int gpio_regmap_get_direction(struct gpio_chip *chip,
>  		return -ENOTSUPP;
>  	}
>  
> -	ret = gpio->reg_mask_xlate(gpio, base, offset, &reg, &mask);
> +	ret = gpio->reg_mask_xlate(gpio, GPIO_REGMAP_GET_DIR_OP, base, offset, &reg, &mask);
>  	if (ret)
>  		return ret;
>  
> @@ -237,7 +270,7 @@ static int gpio_regmap_set_direction(struct gpio_chip *chip,
>  		return -ENOTSUPP;
>  	}
>  
> -	ret = gpio->reg_mask_xlate(gpio, base, offset, &reg, &mask);
> +	ret = gpio->reg_mask_xlate(gpio, GPIO_REGMAP_SET_DIR_OP, base, offset, &reg, &mask);
>  	if (ret)
>  		return ret;
>  
> @@ -246,6 +279,13 @@ static int gpio_regmap_set_direction(struct gpio_chip *chip,
>  	else
>  		val = output ? mask : 0;
>  
> +	if (gpio->value_xlate) {
> +		ret = gpio->value_xlate(gpio, GPIO_REGMAP_SET_DIR_OP, base, offset,
> +					reg, &mask, &val);
> +		if (ret)
> +			return ret;
> +	}
> +
>  	return regmap_update_bits(gpio->regmap, reg, mask, val);
>  }
>  
> @@ -413,6 +453,8 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config
>  	if (!gpio->reg_mask_xlate)
>  		gpio->reg_mask_xlate = gpio_regmap_simple_xlate;
>  
> +	gpio->value_xlate = config->value_xlate;
> +
>  	ret = gpiochip_add_data(chip, gpio);
>  	if (ret < 0)
>  		goto err_free_bitmap_output;
> diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
> index 9ee65d63c525..f78e758706ed 100644
> --- a/drivers/iio/adc/ad7173.c
> +++ b/drivers/iio/adc/ad7173.c
> @@ -560,8 +560,8 @@ static int ad4111_openwire_event(struct iio_dev *indio_dev,
>  	return ret;
>  }
>  
> -static int ad7173_mask_xlate(struct gpio_regmap *gpio, unsigned int base,
> -			     unsigned int offset, unsigned int *reg,
> +static int ad7173_mask_xlate(struct gpio_regmap *gpio, enum gpio_regmap_operation op,
> +			     unsigned int base, unsigned int offset, unsigned int *reg,
>  			     unsigned int *mask)
>  {
>  	*mask = AD7173_GPO_DATA(offset);
> @@ -569,8 +569,8 @@ static int ad7173_mask_xlate(struct gpio_regmap *gpio, unsigned int base,
>  	return 0;
>  }
>  
> -static int ad4111_mask_xlate(struct gpio_regmap *gpio, unsigned int base,
> -			     unsigned int offset, unsigned int *reg,
> +static int ad4111_mask_xlate(struct gpio_regmap *gpio, enum gpio_regmap_operation op,
> +			     unsigned int base, unsigned int offset, unsigned int *reg,
>  			     unsigned int *mask)
>  {
>  	*mask = AD4111_GPO01_DATA(offset);
> diff --git a/drivers/iio/addac/stx104.c b/drivers/iio/addac/stx104.c
> index 7bdf2cb94176..6207eb2fac74 100644
> --- a/drivers/iio/addac/stx104.c
> +++ b/drivers/iio/addac/stx104.c
> @@ -349,9 +349,9 @@ static const struct iio_chan_spec stx104_channels_diff[] = {
>  	STX104_IN_CHAN(6, 1), STX104_IN_CHAN(7, 1)
>  };
>  
> -static int stx104_reg_mask_xlate(struct gpio_regmap *const gpio, const unsigned int base,
> -				 unsigned int offset, unsigned int *const reg,
> -				 unsigned int *const mask)
> +static int stx104_reg_mask_xlate(struct gpio_regmap *const gpio, enum gpio_regmap_operation op,
> +				 const unsigned int base, unsigned int offset,
> +				 unsigned int *const reg, unsigned int *const mask)
>  {
>  	/* Output lines are located at same register bit offsets as input lines */
>  	if (offset >= 4)
> diff --git a/drivers/pinctrl/bcm/pinctrl-bcm63xx.c b/drivers/pinctrl/bcm/pinctrl-bcm63xx.c
> index a4aa4146b530..b41a3d16aabe 100644
> --- a/drivers/pinctrl/bcm/pinctrl-bcm63xx.c
> +++ b/drivers/pinctrl/bcm/pinctrl-bcm63xx.c
> @@ -19,6 +19,7 @@
>  #define BCM63XX_DATA_REG	0x0c
>  
>  static int bcm63xx_reg_mask_xlate(struct gpio_regmap *gpio,
> +				  enum gpio_regmap_operation op,
>  				  unsigned int base, unsigned int offset,
>  				  unsigned int *reg, unsigned int *mask)
>  {
> diff --git a/drivers/pinctrl/pinctrl-tps6594.c b/drivers/pinctrl/pinctrl-tps6594.c
> index 456a3cfc8de9..937fc9cb54b7 100644
> --- a/drivers/pinctrl/pinctrl-tps6594.c
> +++ b/drivers/pinctrl/pinctrl-tps6594.c
> @@ -346,6 +346,7 @@ static struct tps6594_pinctrl tps6594_template_pinctrl = {
>  };
>  
>  static int tps6594_gpio_regmap_xlate(struct gpio_regmap *gpio,
> +				     enum gpio_regmap_operation op,
>  				     unsigned int base, unsigned int offset,
>  				     unsigned int *reg, unsigned int *mask)
>  {
> diff --git a/include/linux/gpio/regmap.h b/include/linux/gpio/regmap.h
> index a3ba8242c353..45a30f50043f 100644
> --- a/include/linux/gpio/regmap.h
> +++ b/include/linux/gpio/regmap.h
> @@ -13,6 +13,36 @@ struct regmap;
>  #define GPIO_REGMAP_ADDR_ZERO ((unsigned int)(-1))
>  #define GPIO_REGMAP_ADDR(addr) ((addr) ? : GPIO_REGMAP_ADDR_ZERO)
>  
> +/**
> + * enum gpio_regmap_operation - Operation type for reg_mask_xlate callback
> + *
> + * This enum is used to distinguish between different types of GPIO operations
> + * so that the reg_mask_xlate callback can return the appropriate mask for each
> + * operation type.
> + *
> + * Value operations:
> + * @GPIO_REGMAP_GET_OP: Mask for reading direction to detect if GPIO is input or output.
> + *                      Used in gpio_regmap_get() to determine the GPIO direction.
> + * @GPIO_REGMAP_IN: Mask for reading input value. Used when GPIO is configured as input.
> + * @GPIO_REGMAP_OUT: Mask for reading output value. Used when GPIO is configured as output.
> + *
> + * Output operations:
> + * @GPIO_REGMAP_SET_OP: Mask for setting GPIO output value.
> + *
> + * Direction operations:
> + * @GPIO_REGMAP_GET_DIR_OP: Mask for reading GPIO direction (input/output).
> + * @GPIO_REGMAP_SET_DIR_OP: Mask for setting GPIO direction (input/output).
> + *
> + */
> +enum gpio_regmap_operation {
> +	GPIO_REGMAP_GET_OP,
> +	GPIO_REGMAP_SET_OP,
> +	GPIO_REGMAP_GET_DIR_OP,
> +	GPIO_REGMAP_SET_DIR_OP,
> +	GPIO_REGMAP_IN,
> +	GPIO_REGMAP_OUT,
> +};
> +
>  /**
>   * struct gpio_regmap_config - Description of a generic regmap gpio_chip.
>   * @parent:		The parent device
> @@ -55,6 +85,10 @@ struct regmap;
>   *			is used.
>   * @init_valid_mask:	(Optional) Routine to initialize @valid_mask, to be used
>   *			if not all GPIOs are valid.
> + * @value_xlate:	(Optional) Routine to translate the register value and
> + *			mask before writing. This allows driver-specific logic
> + *			to append additional bits (like write-enable masks)
> + *			dynamically based on the current operation.
>   * @drvdata:		(Optional) Pointer to driver specific data which is
>   *			not used by gpio-remap but is provided "as is" to the
>   *			driver callback(s).
> @@ -104,14 +138,18 @@ struct gpio_regmap_config {
>  	unsigned long regmap_irq_flags;
>  #endif
>  
> -	int (*reg_mask_xlate)(struct gpio_regmap *gpio, unsigned int base,
> -			      unsigned int offset, unsigned int *reg,
> -			      unsigned int *mask);
> +	int (*reg_mask_xlate)(struct gpio_regmap *gpio, enum gpio_regmap_operation,
> +			      unsigned int base, unsigned int offset,
> +			      unsigned int *reg, unsigned int *mask);
>  
>  	int (*init_valid_mask)(struct gpio_chip *gc,
>  			       unsigned long *valid_mask,
>  			       unsigned int ngpios);
>  
> +	int (*value_xlate)(struct gpio_regmap *gpio, enum gpio_regmap_operation,
> +			   unsigned int base, unsigned int offset, unsigned int reg,
> +			   unsigned int *mask, unsigned int *val);
> +
>  	void *drvdata;
>  };
>