Re: [PATCH v3 07/12] iio: dac: ad5686: add ldac gpio

[David Lechner]

On 6/16/26 3:21 AM, Rodrigo Alencar via B4 Relay wrote:
> From: Rodrigo Alencar <rodrigo.alencar@xxxxxxxxxx>
> 
> If wired LDAC, should be held low when unused (pin is active-low), which

Would better match the implementation if this said "asserted" instead of
"held low" (code says GPIOD_OUT_HIGH which should be read as "asserted").

> allows for synchronous DAC updates. This will be used to update all the
> channels at the same time when adding buffer support.
> 
> Signed-off-by: Rodrigo Alencar <rodrigo.alencar@xxxxxxxxxx>
> ---
>  drivers/iio/dac/ad5686.c | 6 ++++++
>  drivers/iio/dac/ad5686.h | 3 +++
>  2 files changed, 9 insertions(+)
> 
> diff --git a/drivers/iio/dac/ad5686.c b/drivers/iio/dac/ad5686.c
> index a48acedff51c..73105c197964 100644
> --- a/drivers/iio/dac/ad5686.c
> +++ b/drivers/iio/dac/ad5686.c
> @@ -12,6 +12,7 @@
>  #include <linux/dev_printk.h>
>  #include <linux/errno.h>
>  #include <linux/export.h>
> +#include <linux/gpio/consumer.h>
>  #include <linux/kstrtox.h>
>  #include <linux/module.h>
>  #include <linux/regulator/consumer.h>
> @@ -515,6 +516,11 @@ int ad5686_probe(struct device *dev,
>  		return dev_err_probe(dev, PTR_ERR(rstc),
>  				     "Failed to get reset control\n");
>  
> +	st->ldac_gpio = devm_gpiod_get_optional(dev, "ldac", GPIOD_OUT_HIGH);
> +	if (IS_ERR(st->ldac_gpio))
> +		return dev_err_probe(dev, PTR_ERR(st->ldac_gpio),
> +				     "Failed to get LDAC GPIO\n");
> +
>  	reset_control_assert(rstc);
>  	fsleep(1); /* reset pulse: comfortably bigger than the spec */
>  	reset_control_deassert(rstc);
> diff --git a/drivers/iio/dac/ad5686.h b/drivers/iio/dac/ad5686.h
> index a06fe7d89305..f3110410d89b 100644
> --- a/drivers/iio/dac/ad5686.h
> +++ b/drivers/iio/dac/ad5686.h
> @@ -60,6 +60,7 @@ enum ad5686_regmap_type {
>  	AD5686_REGMAP,
>  };
>  
> +struct gpio_desc;
>  struct ad5686_state;
>  
>  /**
> @@ -119,6 +120,7 @@ extern const struct ad5686_chip_info ad5679r_chip_info;
>   * @dev:		device instance
>   * @chip_info:		chip model specific constants, available modes etc
>   * @ops:		bus specific operations
> + * @ldac_gpio:		LDAC pin GPIO descriptor
>   * @vref_mv:		actual reference voltage used
>   * @pwr_down_mask:	power down mask
>   * @pwr_down_mode:	current power down mode
> @@ -131,6 +133,7 @@ struct ad5686_state {
>  	struct device			*dev;
>  	const struct ad5686_chip_info	*chip_info;
>  	const struct ad5686_bus_ops	*ops;
> +	struct gpio_desc		*ldac_gpio;
>  	unsigned short			vref_mv;
>  	unsigned int			pwr_down_mask;
>  	unsigned int			pwr_down_mode;
>