[deliverable/linux.git] / drivers / gpio / devres.c

/*
 * drivers/gpio/devres.c - managed gpio resources
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * This file is based on kernel/irq/devres.c
 *
 * Copyright (c) 2011 John Crispin <blogic@openwrt.org>
 */

#include <linux/module.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/device.h>
#include <linux/gfp.h>

static void devm_gpiod_release(struct device *dev, void *res)
{
	struct gpio_desc **desc = res;

	gpiod_put(*desc);
}

static int devm_gpiod_match(struct device *dev, void *res, void *data)
{
	struct gpio_desc **this = res, **gpio = data;

	return *this == *gpio;
}

/**
 * devm_gpiod_get - Resource-managed gpiod_get()
 * @dev:	GPIO consumer
 * @con_id:	function within the GPIO consumer
 *
 * Managed gpiod_get(). GPIO descriptors returned from this function are
 * automatically disposed on driver detach. See gpiod_get() for detailed
 * information about behavior and return values.
 */
struct gpio_desc *__must_check devm_gpiod_get(struct device *dev,
					      const char *con_id)
{
	return devm_gpiod_get_index(dev, con_id, 0);
}
EXPORT_SYMBOL(devm_gpiod_get);

/**
 * devm_gpiod_get_index - Resource-managed gpiod_get_index()
 * @dev:	GPIO consumer
 * @con_id:	function within the GPIO consumer
 * @idx:	index of the GPIO to obtain in the consumer
 *
 * Managed gpiod_get_index(). GPIO descriptors returned from this function are
 * automatically disposed on driver detach. See gpiod_get_index() for detailed
 * information about behavior and return values.
 */
struct gpio_desc *__must_check devm_gpiod_get_index(struct device *dev,
						    const char *con_id,
						    unsigned int idx)
{
	struct gpio_desc **dr;
	struct gpio_desc *desc;

	dr = devres_alloc(devm_gpiod_release, sizeof(struct gpiod_desc *),
			  GFP_KERNEL);
	if (!dr)
		return ERR_PTR(-ENOMEM);

	desc = gpiod_get_index(dev, con_id, idx);
	if (IS_ERR(desc)) {
		devres_free(dr);
		return desc;
	}

	*dr = desc;
	devres_add(dev, dr);

	return desc;
}
EXPORT_SYMBOL(devm_gpiod_get_index);

/**
 * devm_gpiod_put - Resource-managed gpiod_put()
 * @desc:	GPIO descriptor to dispose of
 *
 * Dispose of a GPIO descriptor obtained with devm_gpiod_get() or
 * devm_gpiod_get_index(). Normally this function will not be called as the GPIO
 * will be disposed of by the resource management code.
 */
void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
{
	WARN_ON(devres_release(dev, devm_gpiod_release, devm_gpiod_match,
		&desc));
}
EXPORT_SYMBOL(devm_gpiod_put);


static void devm_gpio_release(struct device *dev, void *res)
{
	unsigned *gpio = res;

	gpio_free(*gpio);
}

static int devm_gpio_match(struct device *dev, void *res, void *data)
{
	unsigned *this = res, *gpio = data;

	return *this == *gpio;
}

/**
 *      devm_gpio_request - request a GPIO for a managed device
 *      @dev: device to request the GPIO for
 *      @gpio: GPIO to allocate
 *      @label: the name of the requested GPIO
 *
 *      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 an GPIO allocated with this function needs to be freed
 *      separately, devm_gpio_free() must be used.
 */

int devm_gpio_request(struct device *dev, unsigned gpio, const char *label)
{
	unsigned *dr;
	int rc;

	dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
	if (!dr)
		return -ENOMEM;

	rc = gpio_request(gpio, label);
	if (rc) {
		devres_free(dr);
		return rc;
	}

	*dr = gpio;
	devres_add(dev, dr);

	return 0;
}
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;
}
EXPORT_SYMBOL(devm_gpio_request_one);

/**
 *      devm_gpio_free - free a GPIO
 *      @dev: device to free GPIO for
 *      @gpio: GPIO to free
 *
 *      Except for the extra @dev argument, this function takes the
 *      same arguments and performs the same function as gpio_free().
 *      This function instead of gpio_free() should be used to manually
 *      free GPIOs allocated with devm_gpio_request().
 */
void devm_gpio_free(struct device *dev, unsigned int gpio)
{

	WARN_ON(devres_release(dev, devm_gpio_release, devm_gpio_match,
		&gpio));
}
EXPORT_SYMBOL(devm_gpio_free);
Commit	Line	Data
1a0703ed JC	1	/*
	2	* drivers/gpio/devres.c - managed gpio resources
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2
	6	* as published by the Free Software Foundation.
	7	*
	8	* You should have received a copy of the GNU General Public License
	9	* along with this program; if not, write to the Free Software
	10	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	11	*
	12	* This file is based on kernel/irq/devres.c
	13	*
	14	* Copyright (c) 2011 John Crispin <blogic@openwrt.org>
	15	*/
	16
	17	#include <linux/module.h>
3c2c628f	18	#include <linux/err.h>
1a0703ed	19	#include <linux/gpio.h>
3c2c628f	20	#include <linux/gpio/consumer.h>
1a0703ed JC	21	#include <linux/device.h>
	22	#include <linux/gfp.h>
	23
bae48da2 AC	24	static void devm_gpiod_release(struct device dev, void res)
	25	{
	26	struct gpio_desc **desc = res;
	27
	28	gpiod_put(*desc);
	29	}
	30
	31	static int devm_gpiod_match(struct device dev, void res, void *data)
	32	{
	33	struct gpio_desc this = res, gpio = data;
	34
	35	return this == gpio;
	36	}
	37
	38	/**
	39	* devm_gpiod_get - Resource-managed gpiod_get()
	40	* @dev: GPIO consumer
	41	* @con_id: function within the GPIO consumer
	42	*
	43	* Managed gpiod_get(). GPIO descriptors returned from this function are
	44	* automatically disposed on driver detach. See gpiod_get() for detailed
	45	* information about behavior and return values.
	46	*/
	47	struct gpio_desc __must_check devm_gpiod_get(struct device dev,
	48	const char *con_id)
	49	{
	50	return devm_gpiod_get_index(dev, con_id, 0);
	51	}
	52	EXPORT_SYMBOL(devm_gpiod_get);
	53
	54	/**
	55	* devm_gpiod_get_index - Resource-managed gpiod_get_index()
	56	* @dev: GPIO consumer
	57	* @con_id: function within the GPIO consumer
	58	* @idx: index of the GPIO to obtain in the consumer
	59	*
	60	* Managed gpiod_get_index(). GPIO descriptors returned from this function are
	61	* automatically disposed on driver detach. See gpiod_get_index() for detailed
	62	* information about behavior and return values.
	63	*/
	64	struct gpio_desc __must_check devm_gpiod_get_index(struct device dev,
	65	const char *con_id,
	66	unsigned int idx)
	67	{
	68	struct gpio_desc **dr;
	69	struct gpio_desc *desc;
	70
	71	dr = devres_alloc(devm_gpiod_release, sizeof(struct gpiod_desc *),
	72	GFP_KERNEL);
	73	if (!dr)
	74	return ERR_PTR(-ENOMEM);
	75
	76	desc = gpiod_get_index(dev, con_id, idx);
	77	if (IS_ERR(desc)) {
	78	devres_free(dr);
	79	return desc;
	80	}
	81
	82	*dr = desc;
	83	devres_add(dev, dr);
	84
5fcdb9dc	85	return desc;
bae48da2 AC	86	}
	87	EXPORT_SYMBOL(devm_gpiod_get_index);
	88
	89	/**
	90	* devm_gpiod_put - Resource-managed gpiod_put()
	91	* @desc: GPIO descriptor to dispose of
	92	*
	93	* Dispose of a GPIO descriptor obtained with devm_gpiod_get() or
	94	* devm_gpiod_get_index(). Normally this function will not be called as the GPIO
	95	* will be disposed of by the resource management code.
	96	*/
	97	void devm_gpiod_put(struct device dev, struct gpio_desc desc)
	98	{
	99	WARN_ON(devres_release(dev, devm_gpiod_release, devm_gpiod_match,
	100	&desc));
	101	}
	102	EXPORT_SYMBOL(devm_gpiod_put);
	103
	104
	105
	106
1a0703ed JC	107	static void devm_gpio_release(struct device dev, void res)
	108	{
	109	unsigned *gpio = res;
	110
	111	gpio_free(*gpio);
	112	}
	113
	114	static int devm_gpio_match(struct device dev, void res, void *data)
	115	{
	116	unsigned this = res, gpio = data;
	117
	118	return this == gpio;
	119	}
	120
	121	/**
713b7ef8 WS	122	* devm_gpio_request - request a GPIO for a managed device
	123	* @dev: device to request the GPIO for
	124	* @gpio: GPIO to allocate
	125	* @label: the name of the requested GPIO
1a0703ed JC	126	*
	127	* Except for the extra @dev argument, this function takes the
	128	* same arguments and performs the same function as
	129	* gpio_request(). GPIOs requested with this function will be
	130	* automatically freed on driver detach.
	131	*
	132	* If an GPIO allocated with this function needs to be freed
	133	* separately, devm_gpio_free() must be used.
	134	*/
	135
	136	int devm_gpio_request(struct device dev, unsigned gpio, const char label)
	137	{
	138	unsigned *dr;
	139	int rc;
	140
	141	dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
	142	if (!dr)
	143	return -ENOMEM;
	144
	145	rc = gpio_request(gpio, label);
	146	if (rc) {
	147	devres_free(dr);
	148	return rc;
	149	}
	150
	151	*dr = gpio;
	152	devres_add(dev, dr);
	153
	154	return 0;
	155	}
	156	EXPORT_SYMBOL(devm_gpio_request);
	157
09d71ff1 MB	158	/**
	159	* devm_gpio_request_one - request a single GPIO with initial setup
	160	* @dev: device to request for
	161	* @gpio: the GPIO number
	162	* @flags: GPIO configuration as specified by GPIOF_*
	163	* @label: a literal description string of this GPIO
	164	*/
	165	int devm_gpio_request_one(struct device *dev, unsigned gpio,
	166	unsigned long flags, const char *label)
	167	{
	168	unsigned *dr;
	169	int rc;
	170
	171	dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
	172	if (!dr)
	173	return -ENOMEM;
	174
	175	rc = gpio_request_one(gpio, flags, label);
	176	if (rc) {
	177	devres_free(dr);
	178	return rc;
	179	}
	180
	181	*dr = gpio;
	182	devres_add(dev, dr);
	183
	184	return 0;
	185	}
3996bfc7	186	EXPORT_SYMBOL(devm_gpio_request_one);
09d71ff1	187
1a0703ed	188	/**
713b7ef8 WS	189	* devm_gpio_free - free a GPIO
	190	* @dev: device to free GPIO for
	191	* @gpio: GPIO to free
1a0703ed JC	192	*
	193	* Except for the extra @dev argument, this function takes the
	194	* same arguments and performs the same function as gpio_free().
	195	* This function instead of gpio_free() should be used to manually
	196	* free GPIOs allocated with devm_gpio_request().
	197	*/
	198	void devm_gpio_free(struct device *dev, unsigned int gpio)
	199	{
	200
a85990b3	201	WARN_ON(devres_release(dev, devm_gpio_release, devm_gpio_match,
1a0703ed	202	&gpio));
1a0703ed JC	203	}
1a0703ed JC	204	EXPORT_SYMBOL(devm_gpio_free);