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

From: Heiko Stübner
Date: Wed Jun 18 2014 - 09:23:14 EST


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@xxxxxxxxxxxxxxx>
> Signed-off-by: Rob Jones <rob.jones@xxxxxxxxxxxxxxx>

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 */

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/