Re: [PATCH] staging: greybus: use new GPIO line value setter callbacks

[Alex Elder <elder@riscstar.com>]

On 4/7/25 2:14 AM, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> 
> struct gpio_chip now has callbacks for setting line values that return
> an integer, allowing to indicate failures. Convert the driver to using
> them.
> 
> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

Here is the commit that enabled these:
   98ce1eb1fd87e gpiolib: introduce gpio_chip setters that return values

This looks good.  Thank you.

Reviewed-by: Alex Elder <elder@riscstar.com>

> ---
>   drivers/staging/greybus/gpio.c | 16 +++++++++-------
>   1 file changed, 9 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/staging/greybus/gpio.c b/drivers/staging/greybus/gpio.c
> index 16bcf7fc8158..f81c34160f72 100644
> --- a/drivers/staging/greybus/gpio.c
> +++ b/drivers/staging/greybus/gpio.c
> @@ -185,8 +185,8 @@ static int gb_gpio_get_value_operation(struct gb_gpio_controller *ggc,
>   	return 0;
>   }
>   
> -static void gb_gpio_set_value_operation(struct gb_gpio_controller *ggc,
> -					u8 which, bool value_high)
> +static int gb_gpio_set_value_operation(struct gb_gpio_controller *ggc,
> +				       u8 which, bool value_high)
>   {
>   	struct device *dev = &ggc->gbphy_dev->dev;
>   	struct gb_gpio_set_value_request request;
> @@ -195,7 +195,7 @@ static void gb_gpio_set_value_operation(struct gb_gpio_controller *ggc,
>   	if (ggc->lines[which].direction == 1) {
>   		dev_warn(dev, "refusing to set value of input gpio %u\n",
>   			 which);
> -		return;
> +		return -EPERM;
>   	}
>   
>   	request.which = which;
> @@ -204,10 +204,12 @@ static void gb_gpio_set_value_operation(struct gb_gpio_controller *ggc,
>   				&request, sizeof(request), NULL, 0);
>   	if (ret) {
>   		dev_err(dev, "failed to set value of gpio %u\n", which);
> -		return;
> +		return ret;
>   	}
>   
>   	ggc->lines[which].value = request.value;
> +
> +	return 0;
>   }
>   
>   static int gb_gpio_set_debounce_operation(struct gb_gpio_controller *ggc,
> @@ -457,11 +459,11 @@ static int gb_gpio_get(struct gpio_chip *chip, unsigned int offset)
>   	return ggc->lines[which].value;
>   }
>   
> -static void gb_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
> +static int gb_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
>   {
>   	struct gb_gpio_controller *ggc = gpiochip_get_data(chip);
>   
> -	gb_gpio_set_value_operation(ggc, (u8)offset, !!value);
> +	return gb_gpio_set_value_operation(ggc, (u8)offset, !!value);
>   }
>   
>   static int gb_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
> @@ -555,7 +557,7 @@ static int gb_gpio_probe(struct gbphy_device *gbphy_dev,
>   	gpio->direction_input = gb_gpio_direction_input;
>   	gpio->direction_output = gb_gpio_direction_output;
>   	gpio->get = gb_gpio_get;
> -	gpio->set = gb_gpio_set;
> +	gpio->set_rv = gb_gpio_set;
>   	gpio->set_config = gb_gpio_set_config;
>   	gpio->base = -1;		/* Allocate base dynamically */
>   	gpio->ngpio = ggc->line_max + 1;
> 
> ---
> base-commit: 0af2f6be1b4281385b618cb86ad946eded089ac8
> change-id: 20250331-gpiochip-set-rv-greybus-cd2365755186
> 
> Best regards,