Re: [PATCH 1/3] drivers/gpio: devres.c: allow gpio array requests for managed devices

["Heiko Stübner" <heiko@sntech.de>]

Am Dienstag, 10. Juni 2014, 15:41:46 schrieb Rob Jones:
> Add functions devm_gpio_request_array() and devm_gpio_free_array()
> which are exactly analogous to the equivalent non-managed device
> functions gpio_request_array() and gpio_free_array(), which can be
> found in module gpiolib.c.
> 
> Note that if devm_gpio_request_array() fails, no gpios are obtained.
> No indication is provided as to which particular request failed.
> 
> Reviewed-by: Ian Molton <ian.molton@codethink.co.uk>
> Signed-off-by: Rob Jones <rob.jones@codethink.co.uk>

apart from the doc issue below this looks ok to me


> ---
>  drivers/gpio/devres.c |   57
> +++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/gpio.h  |  
>  4 ++++
>  2 files changed, 61 insertions(+)
> 
> diff --git a/drivers/gpio/devres.c b/drivers/gpio/devres.c
> index 307464f..fd95240d 100644
> --- a/drivers/gpio/devres.c
> +++ b/drivers/gpio/devres.c
> @@ -186,6 +186,63 @@ int devm_gpio_request_one(struct device *dev, unsigned
> gpio, EXPORT_SYMBOL(devm_gpio_request_one);
> 
>  /**
> + * devm_gpio_request_array - request multiple GPIOs in a single call
> + *			     for a managed device
> + * @dev:	device requesting the gpio
> + * @array:      array of the 'struct gpio'
> + * @num:        how many GPIOs in the array

@dev uses a tab as spacing, while @array and @num use spaces, might be nice to 
have this consistent.


> + *
> + * Except for the extra @dev argument, this function takes the
> + * same arguments and performs the same function as
> + * gpio_request().  GPIOs requested with this function will be
> + * automatically freed on driver detach.
> + *
> + * If GPIOs allocated with this function need to be freed separately,
> + * devm_gpio_free_array() or devm_gpio_free() must be used.
> + */
> +int devm_gpio_request_array(struct device *dev,
> +			    const struct gpio *array,
> +			    size_t num)
> +{
> +	int i, err = 0;
> +
> +	for (i = 0; i < num; i++, array++) {
> +		err = devm_gpio_request_one(dev,
> +					    array->gpio,
> +					    array->flags,
> +					    array->label);
> +		if (err) {
> +			while (i--)
> +				devm_gpio_free(dev, (--array)->gpio);
> +		}
> +	}
> +
> +	return err;
> +}
> +EXPORT_SYMBOL(devm_gpio_request_array);
> +
> +/**
> + * devm_gpio_free_array - release multiple GPIOs in a single call
> + *			  for a managed device
> + * @dev:	device requesting the gpio
> + * @array:      array of the 'struct gpio'
> + * @num:        how many GPIOs in the array

same here

> + *
> + * Except for the extra @dev argument, this function takes the
> + * same arguments and performs the same function as gpio_free_array().
> + * This function instead of gpio_free_array() should be used to
> + * manually free GPIOs allocated with devm_gpio_request().
> + */
> +void devm_gpio_free_array(struct device *dev,
> +			  const struct gpio *array,
> +			  size_t num)
> +{
> +	while (num--)
> +		devm_gpio_free(dev, (array++)->gpio);
> +}
> +EXPORT_SYMBOL(devm_gpio_free_array);
> +
> +/**
>   *      devm_gpio_free - free a GPIO
>   *      @dev: device to free GPIO for
>   *      @gpio: GPIO to free
> diff --git a/include/linux/gpio.h b/include/linux/gpio.h
> index 85aa5d0..12d5648 100644
> --- a/include/linux/gpio.h
> +++ b/include/linux/gpio.h
> @@ -84,6 +84,10 @@ struct device;
>  int devm_gpio_request(struct device *dev, unsigned gpio, const char
> *label); int devm_gpio_request_one(struct device *dev, unsigned gpio,
>  			  unsigned long flags, const char *label);
> +int devm_gpio_request_array(struct device *dev, const struct gpio *array,
> +			    size_t num);
> +void devm_gpio_free_array(struct device *dev, const struct gpio *array,
> +			 size_t num);
>  void devm_gpio_free(struct device *dev, unsigned int gpio);
> 
>  #else /* ! CONFIG_GPIOLIB */