Commit 331758ee authored by Rojhalat Ibrahim's avatar Rojhalat Ibrahim Committed by Linus Walleij
Browse files

gpiolib: add devm_gpiod_get_array and devm_gpiod_put_array functions 



Add device managed variants of gpiod_get_array() / gpiod_put_array()
functions for conveniently obtaining and disposing of an entire array
of GPIOs with one function call.

Signed-off-by: default avatarRojhalat Ibrahim <imr@rtschenk.de>
Reviewed-by: default avatarAlexandre Courbot <acourbot@nvidia.com>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent 66858527

Documentation/gpio/consumer.txt

+12 −2
Original line number Diff line number Diff line
@@ -107,6 +107,14 @@ Device-managed variants of these functions are also defined: 
							unsigned int index,

							enum gpiod_flags flags)



	struct gpio_descs *devm_gpiod_get_array(struct device *dev,

						const char *con_id,

						enum gpiod_flags flags)



	struct gpio_descs *devm_gpiod_get_array_optional(struct device *dev,

							 const char *con_id,

							 enum gpiod_flags flags)



A GPIO descriptor can be disposed of using the gpiod_put() function:



	void gpiod_put(struct gpio_desc *desc)
@@ -119,10 +127,12 @@ It is strictly forbidden to use a descriptor after calling these functions. 
It is also not allowed to individually release descriptors (using gpiod_put())

from an array acquired with gpiod_get_array().



The device-managed variant is, unsurprisingly:

The device-managed variants are, unsurprisingly:



	void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)



	void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs)





Using GPIOs

===========

drivers/gpio/devres.c

+89 −0
Original line number Diff line number Diff line
@@ -35,6 +35,20 @@ static int devm_gpiod_match(struct device *dev, void *res, void *data) 
	return *this == *gpio;

}



static void devm_gpiod_release_array(struct device *dev, void *res)

{

	struct gpio_descs **descs = res;



	gpiod_put_array(*descs);

}



static int devm_gpiod_match_array(struct device *dev, void *res, void *data)

{

	struct gpio_descs **this = res, **gpios = data;



	return *this == *gpios;

}



/**

 * devm_gpiod_get - Resource-managed gpiod_get()

 * @dev:	GPIO consumer
@@ -185,6 +199,66 @@ struct gpio_desc *__must_check __devm_gpiod_get_index_optional(struct device *de 
}

EXPORT_SYMBOL(__devm_gpiod_get_index_optional);



/**

 * devm_gpiod_get_array - Resource-managed gpiod_get_array()

 * @dev:	GPIO consumer

 * @con_id:	function within the GPIO consumer

 * @flags:	optional GPIO initialization flags

 *

 * Managed gpiod_get_array(). GPIO descriptors returned from this function are

 * automatically disposed on driver detach. See gpiod_get_array() for detailed

 * information about behavior and return values.

 */

struct gpio_descs *__must_check devm_gpiod_get_array(struct device *dev,

						     const char *con_id,

						     enum gpiod_flags flags)

{

	struct gpio_descs **dr;

	struct gpio_descs *descs;



	dr = devres_alloc(devm_gpiod_release_array,

			  sizeof(struct gpio_descs *), GFP_KERNEL);

	if (!dr)

		return ERR_PTR(-ENOMEM);



	descs = gpiod_get_array(dev, con_id, flags);

	if (IS_ERR(descs)) {

		devres_free(dr);

		return descs;

	}



	*dr = descs;

	devres_add(dev, dr);



	return descs;

}

EXPORT_SYMBOL(devm_gpiod_get_array);



/**

 * devm_gpiod_get_array_optional - Resource-managed gpiod_get_array_optional()

 * @dev:	GPIO consumer

 * @con_id:	function within the GPIO consumer

 * @flags:	optional GPIO initialization flags

 *

 * Managed gpiod_get_array_optional(). GPIO descriptors returned from this

 * function are automatically disposed on driver detach.

 * See gpiod_get_array_optional() for detailed information about behavior and

 * return values.

 */

struct gpio_descs *__must_check

devm_gpiod_get_array_optional(struct device *dev, const char *con_id,

			      enum gpiod_flags flags)

{

	struct gpio_descs *descs;



	descs = devm_gpiod_get_array(dev, con_id, flags);

	if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT))

		return NULL;



	return descs;

}

EXPORT_SYMBOL(devm_gpiod_get_array_optional);



/**

 * devm_gpiod_put - Resource-managed gpiod_put()

 * @desc:	GPIO descriptor to dispose of
@@ -200,6 +274,21 @@ void devm_gpiod_put(struct device *dev, struct gpio_desc *desc) 
}

EXPORT_SYMBOL(devm_gpiod_put);



/**

 * devm_gpiod_put_array - Resource-managed gpiod_put_array()

 * @descs:	GPIO descriptor array to dispose of

 *

 * Dispose of an array of GPIO descriptors obtained with devm_gpiod_get_array().

 * Normally this function will not be called as the GPIOs will be disposed of

 * by the resource management code.

 */

void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs)

{

	WARN_ON(devres_release(dev, devm_gpiod_release_array,

			       devm_gpiod_match_array, &descs));

}

EXPORT_SYMBOL(devm_gpiod_put_array);

include/linux/gpio/consumer.h

+30 −0
Original line number Diff line number Diff line
@@ -83,7 +83,14 @@ struct gpio_desc *__must_check __devm_gpiod_get_optional(struct device *dev, 
struct gpio_desc *__must_check

__devm_gpiod_get_index_optional(struct device *dev, const char *con_id,

			      unsigned int index, enum gpiod_flags flags);

struct gpio_descs *__must_check devm_gpiod_get_array(struct device *dev,

						     const char *con_id,

						     enum gpiod_flags flags);

struct gpio_descs *__must_check

devm_gpiod_get_array_optional(struct device *dev, const char *con_id,

			      enum gpiod_flags flags);

void devm_gpiod_put(struct device *dev, struct gpio_desc *desc);

void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs);



int gpiod_get_direction(struct gpio_desc *desc);

int gpiod_direction_input(struct gpio_desc *desc);
@@ -228,6 +235,20 @@ __devm_gpiod_get_index_optional(struct device *dev, const char *con_id, 
	return ERR_PTR(-ENOSYS);

}



static inline struct gpio_descs *__must_check

devm_gpiod_get_array(struct device *dev, const char *con_id,

		     enum gpiod_flags flags)

{

	return ERR_PTR(-ENOSYS);

}



static inline struct gpio_descs *__must_check

devm_gpiod_get_array_optional(struct device *dev, const char *con_id,

			      enum gpiod_flags flags)

{

	return ERR_PTR(-ENOSYS);

}



static inline void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)

{

	might_sleep();
@@ -236,6 +257,15 @@ static inline void devm_gpiod_put(struct device *dev, struct gpio_desc *desc) 
	WARN_ON(1);

}



static inline void devm_gpiod_put_array(struct device *dev,

					struct gpio_descs *descs)

{

	might_sleep();



	/* GPIO can never have been requested */

	WARN_ON(1);

}





static inline int gpiod_get_direction(const struct gpio_desc *desc)

{

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