1 /* SPDX-License-Identifier: GPL-2.0 */
3 * devres.c - managed gpio resources
4 * This file is based on kernel/irq/devres.c
6 * Copyright (c) 2011 John Crispin <john@phrozen.org>
9 #include <linux/module.h>
10 #include <linux/err.h>
11 #include <linux/gpio.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/device.h>
14 #include <linux/gfp.h>
18 static void devm_gpiod_release(struct device
*dev
, void *res
)
20 struct gpio_desc
**desc
= res
;
25 static int devm_gpiod_match(struct device
*dev
, void *res
, void *data
)
27 struct gpio_desc
**this = res
, **gpio
= data
;
29 return *this == *gpio
;
32 static void devm_gpiod_release_array(struct device
*dev
, void *res
)
34 struct gpio_descs
**descs
= res
;
36 gpiod_put_array(*descs
);
39 static int devm_gpiod_match_array(struct device
*dev
, void *res
, void *data
)
41 struct gpio_descs
**this = res
, **gpios
= data
;
43 return *this == *gpios
;
47 * devm_gpiod_get - Resource-managed gpiod_get()
49 * @con_id: function within the GPIO consumer
50 * @flags: optional GPIO initialization flags
52 * Managed gpiod_get(). GPIO descriptors returned from this function are
53 * automatically disposed on driver detach. See gpiod_get() for detailed
54 * information about behavior and return values.
56 struct gpio_desc
*__must_check
devm_gpiod_get(struct device
*dev
,
58 enum gpiod_flags flags
)
60 return devm_gpiod_get_index(dev
, con_id
, 0, flags
);
62 EXPORT_SYMBOL_GPL(devm_gpiod_get
);
65 * devm_gpiod_get_optional - Resource-managed gpiod_get_optional()
67 * @con_id: function within the GPIO consumer
68 * @flags: optional GPIO initialization flags
70 * Managed gpiod_get_optional(). GPIO descriptors returned from this function
71 * are automatically disposed on driver detach. See gpiod_get_optional() for
72 * detailed information about behavior and return values.
74 struct gpio_desc
*__must_check
devm_gpiod_get_optional(struct device
*dev
,
76 enum gpiod_flags flags
)
78 return devm_gpiod_get_index_optional(dev
, con_id
, 0, flags
);
80 EXPORT_SYMBOL_GPL(devm_gpiod_get_optional
);
83 * devm_gpiod_get_index - Resource-managed gpiod_get_index()
85 * @con_id: function within the GPIO consumer
86 * @idx: index of the GPIO to obtain in the consumer
87 * @flags: optional GPIO initialization flags
89 * Managed gpiod_get_index(). GPIO descriptors returned from this function are
90 * automatically disposed on driver detach. See gpiod_get_index() for detailed
91 * information about behavior and return values.
93 struct gpio_desc
*__must_check
devm_gpiod_get_index(struct device
*dev
,
96 enum gpiod_flags flags
)
98 struct gpio_desc
**dr
;
99 struct gpio_desc
*desc
;
101 desc
= gpiod_get_index(dev
, con_id
, idx
, flags
);
106 * For non-exclusive GPIO descriptors, check if this descriptor is
107 * already under resource management by this device.
109 if (flags
& GPIOD_FLAGS_BIT_NONEXCLUSIVE
) {
112 dres
= devres_find(dev
, devm_gpiod_release
,
113 devm_gpiod_match
, &desc
);
118 dr
= devres_alloc(devm_gpiod_release
, sizeof(struct gpio_desc
*),
122 return ERR_PTR(-ENOMEM
);
130 EXPORT_SYMBOL_GPL(devm_gpiod_get_index
);
133 * devm_gpiod_get_from_of_node() - obtain a GPIO from an OF node
134 * @dev: device for lifecycle management
135 * @node: handle of the OF node
136 * @propname: name of the DT property representing the GPIO
137 * @index: index of the GPIO to obtain for the consumer
138 * @dflags: GPIO initialization flags
139 * @label: label to attach to the requested GPIO
142 * On successful request the GPIO pin is configured in accordance with
145 * In case of error an ERR_PTR() is returned.
147 struct gpio_desc
*devm_gpiod_get_from_of_node(struct device
*dev
,
148 struct device_node
*node
,
149 const char *propname
, int index
,
150 enum gpiod_flags dflags
,
153 struct gpio_desc
**dr
;
154 struct gpio_desc
*desc
;
156 desc
= gpiod_get_from_of_node(node
, propname
, index
, dflags
, label
);
161 * For non-exclusive GPIO descriptors, check if this descriptor is
162 * already under resource management by this device.
164 if (dflags
& GPIOD_FLAGS_BIT_NONEXCLUSIVE
) {
167 dres
= devres_find(dev
, devm_gpiod_release
,
168 devm_gpiod_match
, &desc
);
173 dr
= devres_alloc(devm_gpiod_release
, sizeof(struct gpio_desc
*),
177 return ERR_PTR(-ENOMEM
);
185 EXPORT_SYMBOL_GPL(devm_gpiod_get_from_of_node
);
188 * devm_fwnode_gpiod_get_index - get a GPIO descriptor from a given node
189 * @dev: GPIO consumer
190 * @fwnode: firmware node containing GPIO reference
191 * @con_id: function within the GPIO consumer
192 * @index: index of the GPIO to obtain in the consumer
193 * @flags: GPIO initialization flags
194 * @label: label to attach to the requested GPIO
196 * GPIO descriptors returned from this function are automatically disposed on
199 * On successful request the GPIO pin is configured in accordance with
202 struct gpio_desc
*devm_fwnode_gpiod_get_index(struct device
*dev
,
203 struct fwnode_handle
*fwnode
,
204 const char *con_id
, int index
,
205 enum gpiod_flags flags
,
208 struct gpio_desc
**dr
;
209 struct gpio_desc
*desc
;
211 dr
= devres_alloc(devm_gpiod_release
, sizeof(struct gpio_desc
*),
214 return ERR_PTR(-ENOMEM
);
216 desc
= fwnode_gpiod_get_index(fwnode
, con_id
, index
, flags
, label
);
227 EXPORT_SYMBOL_GPL(devm_fwnode_gpiod_get_index
);
230 * devm_gpiod_get_index_optional - Resource-managed gpiod_get_index_optional()
231 * @dev: GPIO consumer
232 * @con_id: function within the GPIO consumer
233 * @index: index of the GPIO to obtain in the consumer
234 * @flags: optional GPIO initialization flags
236 * Managed gpiod_get_index_optional(). GPIO descriptors returned from this
237 * function are automatically disposed on driver detach. See
238 * gpiod_get_index_optional() for detailed information about behavior and
241 struct gpio_desc
*__must_check
devm_gpiod_get_index_optional(struct device
*dev
,
244 enum gpiod_flags flags
)
246 struct gpio_desc
*desc
;
248 desc
= devm_gpiod_get_index(dev
, con_id
, index
, flags
);
250 if (PTR_ERR(desc
) == -ENOENT
)
256 EXPORT_SYMBOL_GPL(devm_gpiod_get_index_optional
);
259 * devm_gpiod_get_array - Resource-managed gpiod_get_array()
260 * @dev: GPIO consumer
261 * @con_id: function within the GPIO consumer
262 * @flags: optional GPIO initialization flags
264 * Managed gpiod_get_array(). GPIO descriptors returned from this function are
265 * automatically disposed on driver detach. See gpiod_get_array() for detailed
266 * information about behavior and return values.
268 struct gpio_descs
*__must_check
devm_gpiod_get_array(struct device
*dev
,
270 enum gpiod_flags flags
)
272 struct gpio_descs
**dr
;
273 struct gpio_descs
*descs
;
275 dr
= devres_alloc(devm_gpiod_release_array
,
276 sizeof(struct gpio_descs
*), GFP_KERNEL
);
278 return ERR_PTR(-ENOMEM
);
280 descs
= gpiod_get_array(dev
, con_id
, flags
);
291 EXPORT_SYMBOL_GPL(devm_gpiod_get_array
);
294 * devm_gpiod_get_array_optional - Resource-managed gpiod_get_array_optional()
295 * @dev: GPIO consumer
296 * @con_id: function within the GPIO consumer
297 * @flags: optional GPIO initialization flags
299 * Managed gpiod_get_array_optional(). GPIO descriptors returned from this
300 * function are automatically disposed on driver detach.
301 * See gpiod_get_array_optional() for detailed information about behavior and
304 struct gpio_descs
*__must_check
305 devm_gpiod_get_array_optional(struct device
*dev
, const char *con_id
,
306 enum gpiod_flags flags
)
308 struct gpio_descs
*descs
;
310 descs
= devm_gpiod_get_array(dev
, con_id
, flags
);
311 if (PTR_ERR(descs
) == -ENOENT
)
316 EXPORT_SYMBOL_GPL(devm_gpiod_get_array_optional
);
319 * devm_gpiod_put - Resource-managed gpiod_put()
320 * @dev: GPIO consumer
321 * @desc: GPIO descriptor to dispose of
323 * Dispose of a GPIO descriptor obtained with devm_gpiod_get() or
324 * devm_gpiod_get_index(). Normally this function will not be called as the GPIO
325 * will be disposed of by the resource management code.
327 void devm_gpiod_put(struct device
*dev
, struct gpio_desc
*desc
)
329 WARN_ON(devres_release(dev
, devm_gpiod_release
, devm_gpiod_match
,
332 EXPORT_SYMBOL_GPL(devm_gpiod_put
);
335 * devm_gpiod_unhinge - Remove resource management from a gpio descriptor
336 * @dev: GPIO consumer
337 * @desc: GPIO descriptor to remove resource management from
339 * Remove resource management from a GPIO descriptor. This is needed when
340 * you want to hand over lifecycle management of a descriptor to another
344 void devm_gpiod_unhinge(struct device
*dev
, struct gpio_desc
*desc
)
348 if (IS_ERR_OR_NULL(desc
))
350 ret
= devres_destroy(dev
, devm_gpiod_release
,
351 devm_gpiod_match
, &desc
);
353 * If the GPIO descriptor is requested as nonexclusive, we
354 * may call this function several times on the same descriptor
355 * so it is OK if devres_destroy() returns -ENOENT.
359 /* Anything else we should warn about */
362 EXPORT_SYMBOL_GPL(devm_gpiod_unhinge
);
365 * devm_gpiod_put_array - Resource-managed gpiod_put_array()
366 * @dev: GPIO consumer
367 * @descs: GPIO descriptor array to dispose of
369 * Dispose of an array of GPIO descriptors obtained with devm_gpiod_get_array().
370 * Normally this function will not be called as the GPIOs will be disposed of
371 * by the resource management code.
373 void devm_gpiod_put_array(struct device
*dev
, struct gpio_descs
*descs
)
375 WARN_ON(devres_release(dev
, devm_gpiod_release_array
,
376 devm_gpiod_match_array
, &descs
));
378 EXPORT_SYMBOL_GPL(devm_gpiod_put_array
);
383 static void devm_gpio_release(struct device
*dev
, void *res
)
385 unsigned *gpio
= res
;
390 static int devm_gpio_match(struct device
*dev
, void *res
, void *data
)
392 unsigned *this = res
, *gpio
= data
;
394 return *this == *gpio
;
398 * devm_gpio_request - request a GPIO for a managed device
399 * @dev: device to request the GPIO for
400 * @gpio: GPIO to allocate
401 * @label: the name of the requested GPIO
403 * Except for the extra @dev argument, this function takes the
404 * same arguments and performs the same function as
405 * gpio_request(). GPIOs requested with this function will be
406 * automatically freed on driver detach.
408 * If an GPIO allocated with this function needs to be freed
409 * separately, devm_gpio_free() must be used.
412 int devm_gpio_request(struct device
*dev
, unsigned gpio
, const char *label
)
417 dr
= devres_alloc(devm_gpio_release
, sizeof(unsigned), GFP_KERNEL
);
421 rc
= gpio_request(gpio
, label
);
432 EXPORT_SYMBOL_GPL(devm_gpio_request
);
435 * devm_gpio_request_one - request a single GPIO with initial setup
436 * @dev: device to request for
437 * @gpio: the GPIO number
438 * @flags: GPIO configuration as specified by GPIOF_*
439 * @label: a literal description string of this GPIO
441 int devm_gpio_request_one(struct device
*dev
, unsigned gpio
,
442 unsigned long flags
, const char *label
)
447 dr
= devres_alloc(devm_gpio_release
, sizeof(unsigned), GFP_KERNEL
);
451 rc
= gpio_request_one(gpio
, flags
, label
);
462 EXPORT_SYMBOL_GPL(devm_gpio_request_one
);
465 * devm_gpio_free - free a GPIO
466 * @dev: device to free GPIO for
467 * @gpio: GPIO to free
469 * Except for the extra @dev argument, this function takes the
470 * same arguments and performs the same function as gpio_free().
471 * This function instead of gpio_free() should be used to manually
472 * free GPIOs allocated with devm_gpio_request().
474 void devm_gpio_free(struct device
*dev
, unsigned int gpio
)
477 WARN_ON(devres_release(dev
, devm_gpio_release
, devm_gpio_match
,
480 EXPORT_SYMBOL_GPL(devm_gpio_free
);