1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * devres.c - managed gpio resources
4 * This file is based on kernel/irq/devres.c
5 *
6 * Copyright (c) 2011 John Crispin <john@phrozen.org>
7 */
8
9#include <linux/device/devres.h>
10#include <linux/err.h>
11#include <linux/export.h>
12#include <linux/gfp.h>
13#include <linux/types.h>
14
15#include <linux/gpio/consumer.h>
16
17#include "gpiolib.h"
18
19struct fwnode_handle;
20struct lock_class_key;
21
22static void devm_gpiod_release(void *desc)
23{
24 gpiod_put(desc);
25}
26
27static void devm_gpiod_release_array(void *descs)
28{
29 gpiod_put_array(descs);
30}
31
32/**
33 * devm_gpiod_get - Resource-managed gpiod_get()
34 * @dev: GPIO consumer
35 * @con_id: function within the GPIO consumer
36 * @flags: optional GPIO initialization flags
37 *
38 * Managed gpiod_get(). GPIO descriptors returned from this function are
39 * automatically disposed on driver detach. See gpiod_get() for detailed
40 * information about behavior and return values.
41 *
42 * Returns:
43 * The GPIO descriptor corresponding to the function @con_id of device
44 * dev, %-ENOENT if no GPIO has been assigned to the requested function, or
45 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
46 */
47struct gpio_desc *__must_check devm_gpiod_get(struct device *dev,
48 const char *con_id,
49 enum gpiod_flags flags)
50{
51 return devm_gpiod_get_index(dev, con_id, idx: 0, flags);
52}
53EXPORT_SYMBOL_GPL(devm_gpiod_get);
54
55/**
56 * devm_gpiod_get_optional - Resource-managed gpiod_get_optional()
57 * @dev: GPIO consumer
58 * @con_id: function within the GPIO consumer
59 * @flags: optional GPIO initialization flags
60 *
61 * Managed gpiod_get_optional(). GPIO descriptors returned from this function
62 * are automatically disposed on driver detach. See gpiod_get_optional() for
63 * detailed information about behavior and return values.
64 *
65 * Returns:
66 * The GPIO descriptor corresponding to the function @con_id of device
67 * dev, NULL if no GPIO has been assigned to the requested function, or
68 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
69 */
70struct gpio_desc *__must_check devm_gpiod_get_optional(struct device *dev,
71 const char *con_id,
72 enum gpiod_flags flags)
73{
74 return devm_gpiod_get_index_optional(dev, con_id, index: 0, flags);
75}
76EXPORT_SYMBOL_GPL(devm_gpiod_get_optional);
77
78/**
79 * devm_gpiod_get_index - Resource-managed gpiod_get_index()
80 * @dev: GPIO consumer
81 * @con_id: function within the GPIO consumer
82 * @idx: index of the GPIO to obtain in the consumer
83 * @flags: optional GPIO initialization flags
84 *
85 * Managed gpiod_get_index(). GPIO descriptors returned from this function are
86 * automatically disposed on driver detach. See gpiod_get_index() for detailed
87 * information about behavior and return values.
88 *
89 * Returns:
90 * The GPIO descriptor corresponding to the function @con_id of device
91 * dev, %-ENOENT if no GPIO has been assigned to the requested function, or
92 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
93 */
94struct gpio_desc *__must_check devm_gpiod_get_index(struct device *dev,
95 const char *con_id,
96 unsigned int idx,
97 enum gpiod_flags flags)
98{
99 struct gpio_desc *desc;
100 int ret;
101
102 desc = gpiod_get_index(dev, con_id, idx, flags);
103 if (IS_ERR(ptr: desc))
104 return desc;
105
106 /*
107 * For non-exclusive GPIO descriptors, check if this descriptor is
108 * already under resource management by this device.
109 */
110 if (flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
111 bool dres;
112
113 dres = devm_is_action_added(dev, action: devm_gpiod_release, data: desc);
114 if (dres)
115 return desc;
116 }
117
118 ret = devm_add_action_or_reset(dev, devm_gpiod_release, desc);
119 if (ret)
120 return ERR_PTR(error: ret);
121
122 return desc;
123}
124EXPORT_SYMBOL_GPL(devm_gpiod_get_index);
125
126/**
127 * devm_fwnode_gpiod_get_index - get a GPIO descriptor from a given node
128 * @dev: GPIO consumer
129 * @fwnode: firmware node containing GPIO reference
130 * @con_id: function within the GPIO consumer
131 * @index: index of the GPIO to obtain in the consumer
132 * @flags: GPIO initialization flags
133 * @label: label to attach to the requested GPIO
134 *
135 * GPIO descriptors returned from this function are automatically disposed on
136 * driver detach.
137 *
138 * Returns:
139 * The GPIO descriptor corresponding to the function @con_id of device
140 * dev, %-ENOENT if no GPIO has been assigned to the requested function, or
141 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
142 */
143struct gpio_desc *devm_fwnode_gpiod_get_index(struct device *dev,
144 struct fwnode_handle *fwnode,
145 const char *con_id, int index,
146 enum gpiod_flags flags,
147 const char *label)
148{
149 struct gpio_desc *desc;
150 int ret;
151
152 desc = gpiod_find_and_request(consumer: dev, fwnode, con_id, idx: index, flags, label, platform_lookup_allowed: false);
153 if (IS_ERR(ptr: desc))
154 return desc;
155
156 ret = devm_add_action_or_reset(dev, devm_gpiod_release, desc);
157 if (ret)
158 return ERR_PTR(error: ret);
159
160 return desc;
161}
162EXPORT_SYMBOL_GPL(devm_fwnode_gpiod_get_index);
163
164/**
165 * devm_gpiod_get_index_optional - Resource-managed gpiod_get_index_optional()
166 * @dev: GPIO consumer
167 * @con_id: function within the GPIO consumer
168 * @index: index of the GPIO to obtain in the consumer
169 * @flags: optional GPIO initialization flags
170 *
171 * Managed gpiod_get_index_optional(). GPIO descriptors returned from this
172 * function are automatically disposed on driver detach. See
173 * gpiod_get_index_optional() for detailed information about behavior and
174 * return values.
175 *
176 * Returns:
177 * The GPIO descriptor corresponding to the function @con_id of device
178 * dev, %NULL if no GPIO has been assigned to the requested function, or
179 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
180 */
181struct gpio_desc *__must_check devm_gpiod_get_index_optional(struct device *dev,
182 const char *con_id,
183 unsigned int index,
184 enum gpiod_flags flags)
185{
186 struct gpio_desc *desc;
187
188 desc = devm_gpiod_get_index(dev, con_id, index, flags);
189 if (gpiod_not_found(desc))
190 return NULL;
191
192 return desc;
193}
194EXPORT_SYMBOL_GPL(devm_gpiod_get_index_optional);
195
196/**
197 * devm_gpiod_get_array - Resource-managed gpiod_get_array()
198 * @dev: GPIO consumer
199 * @con_id: function within the GPIO consumer
200 * @flags: optional GPIO initialization flags
201 *
202 * Managed gpiod_get_array(). GPIO descriptors returned from this function are
203 * automatically disposed on driver detach. See gpiod_get_array() for detailed
204 * information about behavior and return values.
205 *
206 * Returns:
207 * The GPIO descriptors corresponding to the function @con_id of device
208 * dev, %-ENOENT if no GPIO has been assigned to the requested function,
209 * or another IS_ERR() code if an error occurred while trying to acquire
210 * the GPIOs.
211 */
212struct gpio_descs *__must_check devm_gpiod_get_array(struct device *dev,
213 const char *con_id,
214 enum gpiod_flags flags)
215{
216 struct gpio_descs *descs;
217 int ret;
218
219 descs = gpiod_get_array(dev, con_id, flags);
220 if (IS_ERR(ptr: descs))
221 return descs;
222
223 ret = devm_add_action_or_reset(dev, devm_gpiod_release_array, descs);
224 if (ret)
225 return ERR_PTR(error: ret);
226
227 return descs;
228}
229EXPORT_SYMBOL_GPL(devm_gpiod_get_array);
230
231/**
232 * devm_gpiod_get_array_optional - Resource-managed gpiod_get_array_optional()
233 * @dev: GPIO consumer
234 * @con_id: function within the GPIO consumer
235 * @flags: optional GPIO initialization flags
236 *
237 * Managed gpiod_get_array_optional(). GPIO descriptors returned from this
238 * function are automatically disposed on driver detach.
239 * See gpiod_get_array_optional() for detailed information about behavior and
240 * return values.
241 *
242 * Returns:
243 * The GPIO descriptors corresponding to the function @con_id of device
244 * dev, %NULL if no GPIO has been assigned to the requested function,
245 * or another IS_ERR() code if an error occurred while trying to acquire
246 * the GPIOs.
247 */
248struct gpio_descs *__must_check
249devm_gpiod_get_array_optional(struct device *dev, const char *con_id,
250 enum gpiod_flags flags)
251{
252 struct gpio_descs *descs;
253
254 descs = devm_gpiod_get_array(dev, con_id, flags);
255 if (gpiod_not_found(descs))
256 return NULL;
257
258 return descs;
259}
260EXPORT_SYMBOL_GPL(devm_gpiod_get_array_optional);
261
262/**
263 * devm_gpiod_put - Resource-managed gpiod_put()
264 * @dev: GPIO consumer
265 * @desc: GPIO descriptor to dispose of
266 *
267 * Dispose of a GPIO descriptor obtained with devm_gpiod_get() or
268 * devm_gpiod_get_index(). Normally this function will not be called as the GPIO
269 * will be disposed of by the resource management code.
270 */
271void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
272{
273 devm_release_action(dev, action: devm_gpiod_release, data: desc);
274}
275EXPORT_SYMBOL_GPL(devm_gpiod_put);
276
277/**
278 * devm_gpiod_unhinge - Remove resource management from a gpio descriptor
279 * @dev: GPIO consumer
280 * @desc: GPIO descriptor to remove resource management from
281 *
282 * *DEPRECATED*
283 * This function should not be used. It's been provided as a workaround for
284 * resource ownership issues in the regulator framework and should be replaced
285 * with a better solution.
286 *
287 * Remove resource management from a GPIO descriptor. This is needed when
288 * you want to hand over lifecycle management of a descriptor to another
289 * mechanism.
290 */
291void devm_gpiod_unhinge(struct device *dev, struct gpio_desc *desc)
292{
293 int ret;
294
295 if (IS_ERR_OR_NULL(ptr: desc))
296 return;
297
298 /*
299 * If the GPIO descriptor is requested as nonexclusive, we
300 * may call this function several times on the same descriptor
301 * so it is OK if devres_destroy() returns -ENOENT.
302 */
303 ret = devm_remove_action_nowarn(dev, action: devm_gpiod_release, data: desc);
304 if (ret == -ENOENT)
305 return;
306 /* Anything else we should warn about */
307 WARN_ON(ret);
308}
309EXPORT_SYMBOL_GPL(devm_gpiod_unhinge);
310
311/**
312 * devm_gpiod_put_array - Resource-managed gpiod_put_array()
313 * @dev: GPIO consumer
314 * @descs: GPIO descriptor array to dispose of
315 *
316 * Dispose of an array of GPIO descriptors obtained with devm_gpiod_get_array().
317 * Normally this function will not be called as the GPIOs will be disposed of
318 * by the resource management code.
319 */
320void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs)
321{
322 devm_release_action(dev, action: devm_gpiod_release_array, data: descs);
323}
324EXPORT_SYMBOL_GPL(devm_gpiod_put_array);
325
326static void devm_gpio_chip_release(void *data)
327{
328 struct gpio_chip *gc = data;
329
330 gpiochip_remove(gc);
331}
332
333/**
334 * devm_gpiochip_add_data_with_key() - Resource managed gpiochip_add_data_with_key()
335 * @dev: pointer to the device that gpio_chip belongs to.
336 * @gc: the GPIO chip to register
337 * @data: driver-private data associated with this chip
338 * @lock_key: lockdep class for IRQ lock
339 * @request_key: lockdep class for IRQ request
340 *
341 * Context: potentially before irqs will work
342 *
343 * The gpio chip automatically be released when the device is unbound.
344 *
345 * Returns:
346 * A negative errno if the chip can't be registered, such as because the
347 * gc->base is invalid or already associated with a different chip.
348 * Otherwise it returns zero as a success code.
349 */
350int devm_gpiochip_add_data_with_key(struct device *dev, struct gpio_chip *gc, void *data,
351 struct lock_class_key *lock_key,
352 struct lock_class_key *request_key)
353{
354 int ret;
355
356 ret = gpiochip_add_data_with_key(gc, data, lock_key, request_key);
357 if (ret < 0)
358 return ret;
359
360 return devm_add_action_or_reset(dev, devm_gpio_chip_release, gc);
361}
362EXPORT_SYMBOL_GPL(devm_gpiochip_add_data_with_key);
363

source code of linux/drivers/gpio/gpiolib-devres.c