2 * drivers/gpio/devres.c - managed gpio resources
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.
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
12 * This file is based on kernel/irq/devres.c
14 * Copyright (c) 2011 John Crispin <blogic@openwrt.org>
17 #include <linux/module.h>
18 #include <linux/err.h>
19 #include <linux/gpio.h>
20 #include <linux/gpio/consumer.h>
21 #include <linux/device.h>
22 #include <linux/gfp.h>
24 static void devm_gpiod_release(struct device
*dev
, void *res
)
26 struct gpio_desc
**desc
= res
;
31 static int devm_gpiod_match(struct device
*dev
, void *res
, void *data
)
33 struct gpio_desc
**this = res
, **gpio
= data
;
35 return *this == *gpio
;
39 * devm_gpiod_get - Resource-managed gpiod_get()
41 * @con_id: function within the GPIO consumer
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.
47 struct gpio_desc
*__must_check
devm_gpiod_get(struct device
*dev
,
50 return devm_gpiod_get_index(dev
, con_id
, 0);
52 EXPORT_SYMBOL(devm_gpiod_get
);
55 * devm_gpiod_get_optional - Resource-managed gpiod_get_optional()
57 * @con_id: function within the GPIO consumer
59 * Managed gpiod_get_optional(). GPIO descriptors returned from this function
60 * are automatically disposed on driver detach. See gpiod_get_optional() for
61 * detailed information about behavior and return values.
63 struct gpio_desc
*__must_check
devm_gpiod_get_optional(struct device
*dev
,
66 return devm_gpiod_get_index_optional(dev
, con_id
, 0);
68 EXPORT_SYMBOL(devm_gpiod_get_optional
);
71 * devm_gpiod_get_index - Resource-managed gpiod_get_index()
73 * @con_id: function within the GPIO consumer
74 * @idx: index of the GPIO to obtain in the consumer
76 * Managed gpiod_get_index(). GPIO descriptors returned from this function are
77 * automatically disposed on driver detach. See gpiod_get_index() for detailed
78 * information about behavior and return values.
80 struct gpio_desc
*__must_check
devm_gpiod_get_index(struct device
*dev
,
84 struct gpio_desc
**dr
;
85 struct gpio_desc
*desc
;
87 dr
= devres_alloc(devm_gpiod_release
, sizeof(struct gpiod_desc
*),
90 return ERR_PTR(-ENOMEM
);
92 desc
= gpiod_get_index(dev
, con_id
, idx
);
103 EXPORT_SYMBOL(devm_gpiod_get_index
);
106 * devm_gpiod_get_index_optional - Resource-managed gpiod_get_index_optional()
107 * @dev: GPIO consumer
108 * @con_id: function within the GPIO consumer
109 * @index: index of the GPIO to obtain in the consumer
111 * Managed gpiod_get_index_optional(). GPIO descriptors returned from this
112 * function are automatically disposed on driver detach. See
113 * gpiod_get_index_optional() for detailed information about behavior and
116 struct gpio_desc
*__must_check
devm_gpiod_get_index_optional(struct device
*dev
,
120 struct gpio_desc
*desc
;
122 desc
= devm_gpiod_get_index(dev
, con_id
, index
);
124 if (PTR_ERR(desc
) == -ENOENT
)
130 EXPORT_SYMBOL(devm_gpiod_get_index_optional
);
133 * devm_gpiod_put - Resource-managed gpiod_put()
134 * @desc: GPIO descriptor to dispose of
136 * Dispose of a GPIO descriptor obtained with devm_gpiod_get() or
137 * devm_gpiod_get_index(). Normally this function will not be called as the GPIO
138 * will be disposed of by the resource management code.
140 void devm_gpiod_put(struct device
*dev
, struct gpio_desc
*desc
)
142 WARN_ON(devres_release(dev
, devm_gpiod_release
, devm_gpiod_match
,
145 EXPORT_SYMBOL(devm_gpiod_put
);
150 static void devm_gpio_release(struct device
*dev
, void *res
)
152 unsigned *gpio
= res
;
157 static int devm_gpio_match(struct device
*dev
, void *res
, void *data
)
159 unsigned *this = res
, *gpio
= data
;
161 return *this == *gpio
;
165 * devm_gpio_request - request a GPIO for a managed device
166 * @dev: device to request the GPIO for
167 * @gpio: GPIO to allocate
168 * @label: the name of the requested GPIO
170 * Except for the extra @dev argument, this function takes the
171 * same arguments and performs the same function as
172 * gpio_request(). GPIOs requested with this function will be
173 * automatically freed on driver detach.
175 * If an GPIO allocated with this function needs to be freed
176 * separately, devm_gpio_free() must be used.
179 int devm_gpio_request(struct device
*dev
, unsigned gpio
, const char *label
)
184 dr
= devres_alloc(devm_gpio_release
, sizeof(unsigned), GFP_KERNEL
);
188 rc
= gpio_request(gpio
, label
);
199 EXPORT_SYMBOL(devm_gpio_request
);
202 * devm_gpio_request_one - request a single GPIO with initial setup
203 * @dev: device to request for
204 * @gpio: the GPIO number
205 * @flags: GPIO configuration as specified by GPIOF_*
206 * @label: a literal description string of this GPIO
208 int devm_gpio_request_one(struct device
*dev
, unsigned gpio
,
209 unsigned long flags
, const char *label
)
214 dr
= devres_alloc(devm_gpio_release
, sizeof(unsigned), GFP_KERNEL
);
218 rc
= gpio_request_one(gpio
, flags
, label
);
229 EXPORT_SYMBOL(devm_gpio_request_one
);
232 * devm_gpio_free - free a GPIO
233 * @dev: device to free GPIO for
234 * @gpio: GPIO to free
236 * Except for the extra @dev argument, this function takes the
237 * same arguments and performs the same function as gpio_free().
238 * This function instead of gpio_free() should be used to manually
239 * free GPIOs allocated with devm_gpio_request().
241 void devm_gpio_free(struct device
*dev
, unsigned int gpio
)
244 WARN_ON(devres_release(dev
, devm_gpio_release
, devm_gpio_match
,
247 EXPORT_SYMBOL(devm_gpio_free
);