Commit 09d71ff1 authored by Mark Brown's avatar Mark Brown Committed by Grant Likely
Browse files

gpiolib: Implement devm_gpio_request_one() 



Allow drivers to use the modern request and configure idiom together
with devres.

As with plain gpio_request() and gpio_request_one() we can't implement
the old school version in terms of _one() as this would force the
explicit selection of a direction in gpio_request() which could break
systems if we pick the wrong one.  Implementing devm_gpio_request_one()
in terms of devm_gpio_request() would needlessly complicate things or
lead to duplication from the unmanaged version depending on how it's
done.

Signed-off-by: default avatarMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: default avatarGrant Likely <grant.likely@secretlab.ca>
parent eb1567f7

drivers/gpio/devres.c

+29 −0
Original line number Diff line number Diff line
@@ -70,6 +70,35 @@ int devm_gpio_request(struct device *dev, unsigned gpio, const char *label) 
}

EXPORT_SYMBOL(devm_gpio_request);



/**

 *	devm_gpio_request_one - request a single GPIO with initial setup

 *	@dev:   device to request for

 *	@gpio:	the GPIO number

 *	@flags:	GPIO configuration as specified by GPIOF_*

 *	@label:	a literal description string of this GPIO

 */

int devm_gpio_request_one(struct device *dev, unsigned gpio,

			  unsigned long flags, const char *label)

{

	unsigned *dr;

	int rc;



	dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);

	if (!dr)

		return -ENOMEM;



	rc = gpio_request_one(gpio, flags, label);

	if (rc) {

		devres_free(dr);

		return rc;

	}



	*dr = gpio;

	devres_add(dev, dr);



	return 0;

}



/**

 *      devm_gpio_free - free an interrupt

 *      @dev: device to free gpio for

include/asm-generic/gpio.h

+2 −0
Original line number Diff line number Diff line
@@ -179,6 +179,8 @@ extern void gpio_free_array(const struct gpio *array, size_t num); 


/* bindings for managed devices that want to request gpios */

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);

void devm_gpio_free(struct device *dev, unsigned int gpio);



#ifdef CONFIG_GPIO_SYSFS

include/linux/gpio.h

+6 −0
Original line number Diff line number Diff line
@@ -106,6 +106,12 @@ static inline int gpio_request_one(unsigned gpio, 
	return -ENOSYS;

}



static inline int devm_gpio_request_one(struct device *dev, unsigned gpio,

					unsigned long flags, const char *label)

{

	return -ENOSYS;

}



static inline int gpio_request_array(const struct gpio *array, size_t num)

{

	return -ENOSYS;

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