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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.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(struct device *dev, void *res)
23{
24 struct gpio_desc **desc = res;
25
26 gpiod_put(*desc);
27}
28
29static int devm_gpiod_match(struct device *dev, void *res, void *data)
30{
31 struct gpio_desc **this = res, **gpio = data;
32
33 return *this == *gpio;
34}
35
36static void devm_gpiod_release_array(struct device *dev, void *res)
37{
38 struct gpio_descs **descs = res;
39
40 gpiod_put_array(*descs);
41}
42
43static int devm_gpiod_match_array(struct device *dev, void *res, void *data)
44{
45 struct gpio_descs **this = res, **gpios = data;
46
47 return *this == *gpios;
48}
49
50/**
51 * devm_gpiod_get - Resource-managed gpiod_get()
52 * @dev: GPIO consumer
53 * @con_id: function within the GPIO consumer
54 * @flags: optional GPIO initialization flags
55 *
56 * Managed gpiod_get(). GPIO descriptors returned from this function are
57 * automatically disposed on driver detach. See gpiod_get() for detailed
58 * information about behavior and return values.
59 *
60 * Returns:
61 * The GPIO descriptor corresponding to the function @con_id of device
62 * dev, %-ENOENT if no GPIO has been assigned to the requested function, or
63 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
64 */
65struct gpio_desc *__must_check devm_gpiod_get(struct device *dev,
66 const char *con_id,
67 enum gpiod_flags flags)
68{
69 return devm_gpiod_get_index(dev, con_id, 0, flags);
70}
71EXPORT_SYMBOL_GPL(devm_gpiod_get);
72
73/**
74 * devm_gpiod_get_optional - Resource-managed gpiod_get_optional()
75 * @dev: GPIO consumer
76 * @con_id: function within the GPIO consumer
77 * @flags: optional GPIO initialization flags
78 *
79 * Managed gpiod_get_optional(). GPIO descriptors returned from this function
80 * are automatically disposed on driver detach. See gpiod_get_optional() for
81 * detailed information about behavior and return values.
82 *
83 * Returns:
84 * The GPIO descriptor corresponding to the function @con_id of device
85 * dev, NULL if no GPIO has been assigned to the requested function, or
86 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
87 */
88struct gpio_desc *__must_check devm_gpiod_get_optional(struct device *dev,
89 const char *con_id,
90 enum gpiod_flags flags)
91{
92 return devm_gpiod_get_index_optional(dev, con_id, 0, flags);
93}
94EXPORT_SYMBOL_GPL(devm_gpiod_get_optional);
95
96/**
97 * devm_gpiod_get_index - Resource-managed gpiod_get_index()
98 * @dev: GPIO consumer
99 * @con_id: function within the GPIO consumer
100 * @idx: index of the GPIO to obtain in the consumer
101 * @flags: optional GPIO initialization flags
102 *
103 * Managed gpiod_get_index(). GPIO descriptors returned from this function are
104 * automatically disposed on driver detach. See gpiod_get_index() for detailed
105 * information about behavior and return values.
106 *
107 * Returns:
108 * The GPIO descriptor corresponding to the function @con_id of device
109 * dev, %-ENOENT if no GPIO has been assigned to the requested function, or
110 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
111 */
112struct gpio_desc *__must_check devm_gpiod_get_index(struct device *dev,
113 const char *con_id,
114 unsigned int idx,
115 enum gpiod_flags flags)
116{
117 struct gpio_desc **dr;
118 struct gpio_desc *desc;
119
120 desc = gpiod_get_index(dev, con_id, idx, flags);
121 if (IS_ERR(desc))
122 return desc;
123
124 /*
125 * For non-exclusive GPIO descriptors, check if this descriptor is
126 * already under resource management by this device.
127 */
128 if (flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
129 struct devres *dres;
130
131 dres = devres_find(dev, devm_gpiod_release,
132 devm_gpiod_match, &desc);
133 if (dres)
134 return desc;
135 }
136
137 dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
138 GFP_KERNEL);
139 if (!dr) {
140 gpiod_put(desc);
141 return ERR_PTR(-ENOMEM);
142 }
143
144 *dr = desc;
145 devres_add(dev, dr);
146
147 return desc;
148}
149EXPORT_SYMBOL_GPL(devm_gpiod_get_index);
150
151/**
152 * devm_fwnode_gpiod_get_index - get a GPIO descriptor from a given node
153 * @dev: GPIO consumer
154 * @fwnode: firmware node containing GPIO reference
155 * @con_id: function within the GPIO consumer
156 * @index: index of the GPIO to obtain in the consumer
157 * @flags: GPIO initialization flags
158 * @label: label to attach to the requested GPIO
159 *
160 * GPIO descriptors returned from this function are automatically disposed on
161 * driver detach.
162 *
163 * Returns:
164 * The GPIO descriptor corresponding to the function @con_id of device
165 * dev, %-ENOENT if no GPIO has been assigned to the requested function, or
166 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
167 */
168struct gpio_desc *devm_fwnode_gpiod_get_index(struct device *dev,
169 struct fwnode_handle *fwnode,
170 const char *con_id, int index,
171 enum gpiod_flags flags,
172 const char *label)
173{
174 struct gpio_desc **dr;
175 struct gpio_desc *desc;
176
177 dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
178 GFP_KERNEL);
179 if (!dr)
180 return ERR_PTR(-ENOMEM);
181
182 desc = gpiod_find_and_request(dev, fwnode, con_id, index, flags, label, false);
183 if (IS_ERR(desc)) {
184 devres_free(dr);
185 return desc;
186 }
187
188 *dr = desc;
189 devres_add(dev, dr);
190
191 return desc;
192}
193EXPORT_SYMBOL_GPL(devm_fwnode_gpiod_get_index);
194
195/**
196 * devm_gpiod_get_index_optional - Resource-managed gpiod_get_index_optional()
197 * @dev: GPIO consumer
198 * @con_id: function within the GPIO consumer
199 * @index: index of the GPIO to obtain in the consumer
200 * @flags: optional GPIO initialization flags
201 *
202 * Managed gpiod_get_index_optional(). GPIO descriptors returned from this
203 * function are automatically disposed on driver detach. See
204 * gpiod_get_index_optional() for detailed information about behavior and
205 * return values.
206 *
207 * Returns:
208 * The GPIO descriptor corresponding to the function @con_id of device
209 * dev, %NULL if no GPIO has been assigned to the requested function, or
210 * another IS_ERR() code if an error occurred while trying to acquire the GPIO.
211 */
212struct gpio_desc *__must_check devm_gpiod_get_index_optional(struct device *dev,
213 const char *con_id,
214 unsigned int index,
215 enum gpiod_flags flags)
216{
217 struct gpio_desc *desc;
218
219 desc = devm_gpiod_get_index(dev, con_id, index, flags);
220 if (gpiod_not_found(desc))
221 return NULL;
222
223 return desc;
224}
225EXPORT_SYMBOL_GPL(devm_gpiod_get_index_optional);
226
227/**
228 * devm_gpiod_get_array - Resource-managed gpiod_get_array()
229 * @dev: GPIO consumer
230 * @con_id: function within the GPIO consumer
231 * @flags: optional GPIO initialization flags
232 *
233 * Managed gpiod_get_array(). GPIO descriptors returned from this function are
234 * automatically disposed on driver detach. See gpiod_get_array() for detailed
235 * information about behavior and return values.
236 *
237 * Returns:
238 * The GPIO descriptors corresponding to the function @con_id of device
239 * dev, %-ENOENT if no GPIO has been assigned to the requested function,
240 * or another IS_ERR() code if an error occurred while trying to acquire
241 * the GPIOs.
242 */
243struct gpio_descs *__must_check devm_gpiod_get_array(struct device *dev,
244 const char *con_id,
245 enum gpiod_flags flags)
246{
247 struct gpio_descs **dr;
248 struct gpio_descs *descs;
249
250 dr = devres_alloc(devm_gpiod_release_array,
251 sizeof(struct gpio_descs *), GFP_KERNEL);
252 if (!dr)
253 return ERR_PTR(-ENOMEM);
254
255 descs = gpiod_get_array(dev, con_id, flags);
256 if (IS_ERR(descs)) {
257 devres_free(dr);
258 return descs;
259 }
260
261 *dr = descs;
262 devres_add(dev, dr);
263
264 return descs;
265}
266EXPORT_SYMBOL_GPL(devm_gpiod_get_array);
267
268/**
269 * devm_gpiod_get_array_optional - Resource-managed gpiod_get_array_optional()
270 * @dev: GPIO consumer
271 * @con_id: function within the GPIO consumer
272 * @flags: optional GPIO initialization flags
273 *
274 * Managed gpiod_get_array_optional(). GPIO descriptors returned from this
275 * function are automatically disposed on driver detach.
276 * See gpiod_get_array_optional() for detailed information about behavior and
277 * return values.
278 *
279 * Returns:
280 * The GPIO descriptors corresponding to the function @con_id of device
281 * dev, %NULL if no GPIO has been assigned to the requested function,
282 * or another IS_ERR() code if an error occurred while trying to acquire
283 * the GPIOs.
284 */
285struct gpio_descs *__must_check
286devm_gpiod_get_array_optional(struct device *dev, const char *con_id,
287 enum gpiod_flags flags)
288{
289 struct gpio_descs *descs;
290
291 descs = devm_gpiod_get_array(dev, con_id, flags);
292 if (gpiod_not_found(descs))
293 return NULL;
294
295 return descs;
296}
297EXPORT_SYMBOL_GPL(devm_gpiod_get_array_optional);
298
299/**
300 * devm_gpiod_put - Resource-managed gpiod_put()
301 * @dev: GPIO consumer
302 * @desc: GPIO descriptor to dispose of
303 *
304 * Dispose of a GPIO descriptor obtained with devm_gpiod_get() or
305 * devm_gpiod_get_index(). Normally this function will not be called as the GPIO
306 * will be disposed of by the resource management code.
307 */
308void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
309{
310 WARN_ON(devres_release(dev, devm_gpiod_release, devm_gpiod_match,
311 &desc));
312}
313EXPORT_SYMBOL_GPL(devm_gpiod_put);
314
315/**
316 * devm_gpiod_unhinge - Remove resource management from a gpio descriptor
317 * @dev: GPIO consumer
318 * @desc: GPIO descriptor to remove resource management from
319 *
320 * Remove resource management from a GPIO descriptor. This is needed when
321 * you want to hand over lifecycle management of a descriptor to another
322 * mechanism.
323 */
324
325void devm_gpiod_unhinge(struct device *dev, struct gpio_desc *desc)
326{
327 int ret;
328
329 if (IS_ERR_OR_NULL(desc))
330 return;
331 ret = devres_destroy(dev, devm_gpiod_release,
332 devm_gpiod_match, &desc);
333 /*
334 * If the GPIO descriptor is requested as nonexclusive, we
335 * may call this function several times on the same descriptor
336 * so it is OK if devres_destroy() returns -ENOENT.
337 */
338 if (ret == -ENOENT)
339 return;
340 /* Anything else we should warn about */
341 WARN_ON(ret);
342}
343EXPORT_SYMBOL_GPL(devm_gpiod_unhinge);
344
345/**
346 * devm_gpiod_put_array - Resource-managed gpiod_put_array()
347 * @dev: GPIO consumer
348 * @descs: GPIO descriptor array to dispose of
349 *
350 * Dispose of an array of GPIO descriptors obtained with devm_gpiod_get_array().
351 * Normally this function will not be called as the GPIOs will be disposed of
352 * by the resource management code.
353 */
354void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs)
355{
356 WARN_ON(devres_release(dev, devm_gpiod_release_array,
357 devm_gpiod_match_array, &descs));
358}
359EXPORT_SYMBOL_GPL(devm_gpiod_put_array);
360
361static void devm_gpio_chip_release(void *data)
362{
363 struct gpio_chip *gc = data;
364
365 gpiochip_remove(gc);
366}
367
368/**
369 * devm_gpiochip_add_data_with_key() - Resource managed gpiochip_add_data_with_key()
370 * @dev: pointer to the device that gpio_chip belongs to.
371 * @gc: the GPIO chip to register
372 * @data: driver-private data associated with this chip
373 * @lock_key: lockdep class for IRQ lock
374 * @request_key: lockdep class for IRQ request
375 *
376 * Context: potentially before irqs will work
377 *
378 * The gpio chip automatically be released when the device is unbound.
379 *
380 * Returns:
381 * A negative errno if the chip can't be registered, such as because the
382 * gc->base is invalid or already associated with a different chip.
383 * Otherwise it returns zero as a success code.
384 */
385int devm_gpiochip_add_data_with_key(struct device *dev, struct gpio_chip *gc, void *data,
386 struct lock_class_key *lock_key,
387 struct lock_class_key *request_key)
388{
389 int ret;
390
391 ret = gpiochip_add_data_with_key(gc, data, lock_key, request_key);
392 if (ret < 0)
393 return ret;
394
395 return devm_add_action_or_reset(dev, devm_gpio_chip_release, gc);
396}
397EXPORT_SYMBOL_GPL(devm_gpiochip_add_data_with_key);
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/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>
15
16#include "gpiolib.h"
17
18static void devm_gpiod_release(struct device *dev, void *res)
19{
20 struct gpio_desc **desc = res;
21
22 gpiod_put(*desc);
23}
24
25static int devm_gpiod_match(struct device *dev, void *res, void *data)
26{
27 struct gpio_desc **this = res, **gpio = data;
28
29 return *this == *gpio;
30}
31
32static void devm_gpiod_release_array(struct device *dev, void *res)
33{
34 struct gpio_descs **descs = res;
35
36 gpiod_put_array(*descs);
37}
38
39static int devm_gpiod_match_array(struct device *dev, void *res, void *data)
40{
41 struct gpio_descs **this = res, **gpios = data;
42
43 return *this == *gpios;
44}
45
46/**
47 * devm_gpiod_get - Resource-managed gpiod_get()
48 * @dev: GPIO consumer
49 * @con_id: function within the GPIO consumer
50 * @flags: optional GPIO initialization flags
51 *
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.
55 */
56struct gpio_desc *__must_check devm_gpiod_get(struct device *dev,
57 const char *con_id,
58 enum gpiod_flags flags)
59{
60 return devm_gpiod_get_index(dev, con_id, 0, flags);
61}
62EXPORT_SYMBOL_GPL(devm_gpiod_get);
63
64/**
65 * devm_gpiod_get_optional - Resource-managed gpiod_get_optional()
66 * @dev: GPIO consumer
67 * @con_id: function within the GPIO consumer
68 * @flags: optional GPIO initialization flags
69 *
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.
73 */
74struct gpio_desc *__must_check devm_gpiod_get_optional(struct device *dev,
75 const char *con_id,
76 enum gpiod_flags flags)
77{
78 return devm_gpiod_get_index_optional(dev, con_id, 0, flags);
79}
80EXPORT_SYMBOL_GPL(devm_gpiod_get_optional);
81
82/**
83 * devm_gpiod_get_index - Resource-managed gpiod_get_index()
84 * @dev: GPIO consumer
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
88 *
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.
92 */
93struct gpio_desc *__must_check devm_gpiod_get_index(struct device *dev,
94 const char *con_id,
95 unsigned int idx,
96 enum gpiod_flags flags)
97{
98 struct gpio_desc **dr;
99 struct gpio_desc *desc;
100
101 desc = gpiod_get_index(dev, con_id, idx, flags);
102 if (IS_ERR(desc))
103 return desc;
104
105 /*
106 * For non-exclusive GPIO descriptors, check if this descriptor is
107 * already under resource management by this device.
108 */
109 if (flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
110 struct devres *dres;
111
112 dres = devres_find(dev, devm_gpiod_release,
113 devm_gpiod_match, &desc);
114 if (dres)
115 return desc;
116 }
117
118 dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
119 GFP_KERNEL);
120 if (!dr) {
121 gpiod_put(desc);
122 return ERR_PTR(-ENOMEM);
123 }
124
125 *dr = desc;
126 devres_add(dev, dr);
127
128 return desc;
129}
130EXPORT_SYMBOL_GPL(devm_gpiod_get_index);
131
132/**
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
140 *
141 * Returns:
142 * On successful request the GPIO pin is configured in accordance with
143 * provided @dflags.
144 *
145 * In case of error an ERR_PTR() is returned.
146 */
147struct 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,
151 const char *label)
152{
153 struct gpio_desc **dr;
154 struct gpio_desc *desc;
155
156 desc = gpiod_get_from_of_node(node, propname, index, dflags, label);
157 if (IS_ERR(desc))
158 return desc;
159
160 /*
161 * For non-exclusive GPIO descriptors, check if this descriptor is
162 * already under resource management by this device.
163 */
164 if (dflags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) {
165 struct devres *dres;
166
167 dres = devres_find(dev, devm_gpiod_release,
168 devm_gpiod_match, &desc);
169 if (dres)
170 return desc;
171 }
172
173 dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
174 GFP_KERNEL);
175 if (!dr) {
176 gpiod_put(desc);
177 return ERR_PTR(-ENOMEM);
178 }
179
180 *dr = desc;
181 devres_add(dev, dr);
182
183 return desc;
184}
185EXPORT_SYMBOL_GPL(devm_gpiod_get_from_of_node);
186
187/**
188 * devm_fwnode_get_index_gpiod_from_child - get a GPIO descriptor from a
189 * device's child node
190 * @dev: GPIO consumer
191 * @con_id: function within the GPIO consumer
192 * @index: index of the GPIO to obtain in the consumer
193 * @child: firmware node (child of @dev)
194 * @flags: GPIO initialization flags
195 * @label: label to attach to the requested GPIO
196 *
197 * GPIO descriptors returned from this function are automatically disposed on
198 * driver detach.
199 *
200 * On successful request the GPIO pin is configured in accordance with
201 * provided @flags.
202 */
203struct gpio_desc *devm_fwnode_get_index_gpiod_from_child(struct device *dev,
204 const char *con_id, int index,
205 struct fwnode_handle *child,
206 enum gpiod_flags flags,
207 const char *label)
208{
209 char prop_name[32]; /* 32 is max size of property name */
210 struct gpio_desc **dr;
211 struct gpio_desc *desc;
212 unsigned int i;
213
214 dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
215 GFP_KERNEL);
216 if (!dr)
217 return ERR_PTR(-ENOMEM);
218
219 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
220 if (con_id)
221 snprintf(prop_name, sizeof(prop_name), "%s-%s",
222 con_id, gpio_suffixes[i]);
223 else
224 snprintf(prop_name, sizeof(prop_name), "%s",
225 gpio_suffixes[i]);
226
227 desc = fwnode_get_named_gpiod(child, prop_name, index, flags,
228 label);
229 if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
230 break;
231 }
232 if (IS_ERR(desc)) {
233 devres_free(dr);
234 return desc;
235 }
236
237 *dr = desc;
238 devres_add(dev, dr);
239
240 return desc;
241}
242EXPORT_SYMBOL_GPL(devm_fwnode_get_index_gpiod_from_child);
243
244/**
245 * devm_gpiod_get_index_optional - Resource-managed gpiod_get_index_optional()
246 * @dev: GPIO consumer
247 * @con_id: function within the GPIO consumer
248 * @index: index of the GPIO to obtain in the consumer
249 * @flags: optional GPIO initialization flags
250 *
251 * Managed gpiod_get_index_optional(). GPIO descriptors returned from this
252 * function are automatically disposed on driver detach. See
253 * gpiod_get_index_optional() for detailed information about behavior and
254 * return values.
255 */
256struct gpio_desc *__must_check devm_gpiod_get_index_optional(struct device *dev,
257 const char *con_id,
258 unsigned int index,
259 enum gpiod_flags flags)
260{
261 struct gpio_desc *desc;
262
263 desc = devm_gpiod_get_index(dev, con_id, index, flags);
264 if (IS_ERR(desc)) {
265 if (PTR_ERR(desc) == -ENOENT)
266 return NULL;
267 }
268
269 return desc;
270}
271EXPORT_SYMBOL_GPL(devm_gpiod_get_index_optional);
272
273/**
274 * devm_gpiod_get_array - Resource-managed gpiod_get_array()
275 * @dev: GPIO consumer
276 * @con_id: function within the GPIO consumer
277 * @flags: optional GPIO initialization flags
278 *
279 * Managed gpiod_get_array(). GPIO descriptors returned from this function are
280 * automatically disposed on driver detach. See gpiod_get_array() for detailed
281 * information about behavior and return values.
282 */
283struct gpio_descs *__must_check devm_gpiod_get_array(struct device *dev,
284 const char *con_id,
285 enum gpiod_flags flags)
286{
287 struct gpio_descs **dr;
288 struct gpio_descs *descs;
289
290 dr = devres_alloc(devm_gpiod_release_array,
291 sizeof(struct gpio_descs *), GFP_KERNEL);
292 if (!dr)
293 return ERR_PTR(-ENOMEM);
294
295 descs = gpiod_get_array(dev, con_id, flags);
296 if (IS_ERR(descs)) {
297 devres_free(dr);
298 return descs;
299 }
300
301 *dr = descs;
302 devres_add(dev, dr);
303
304 return descs;
305}
306EXPORT_SYMBOL_GPL(devm_gpiod_get_array);
307
308/**
309 * devm_gpiod_get_array_optional - Resource-managed gpiod_get_array_optional()
310 * @dev: GPIO consumer
311 * @con_id: function within the GPIO consumer
312 * @flags: optional GPIO initialization flags
313 *
314 * Managed gpiod_get_array_optional(). GPIO descriptors returned from this
315 * function are automatically disposed on driver detach.
316 * See gpiod_get_array_optional() for detailed information about behavior and
317 * return values.
318 */
319struct gpio_descs *__must_check
320devm_gpiod_get_array_optional(struct device *dev, const char *con_id,
321 enum gpiod_flags flags)
322{
323 struct gpio_descs *descs;
324
325 descs = devm_gpiod_get_array(dev, con_id, flags);
326 if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT))
327 return NULL;
328
329 return descs;
330}
331EXPORT_SYMBOL_GPL(devm_gpiod_get_array_optional);
332
333/**
334 * devm_gpiod_put - Resource-managed gpiod_put()
335 * @dev: GPIO consumer
336 * @desc: GPIO descriptor to dispose of
337 *
338 * Dispose of a GPIO descriptor obtained with devm_gpiod_get() or
339 * devm_gpiod_get_index(). Normally this function will not be called as the GPIO
340 * will be disposed of by the resource management code.
341 */
342void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
343{
344 WARN_ON(devres_release(dev, devm_gpiod_release, devm_gpiod_match,
345 &desc));
346}
347EXPORT_SYMBOL_GPL(devm_gpiod_put);
348
349/**
350 * devm_gpiod_unhinge - Remove resource management from a gpio descriptor
351 * @dev: GPIO consumer
352 * @desc: GPIO descriptor to remove resource management from
353 *
354 * Remove resource management from a GPIO descriptor. This is needed when
355 * you want to hand over lifecycle management of a descriptor to another
356 * mechanism.
357 */
358
359void devm_gpiod_unhinge(struct device *dev, struct gpio_desc *desc)
360{
361 int ret;
362
363 if (IS_ERR_OR_NULL(desc))
364 return;
365 ret = devres_destroy(dev, devm_gpiod_release,
366 devm_gpiod_match, &desc);
367 /*
368 * If the GPIO descriptor is requested as nonexclusive, we
369 * may call this function several times on the same descriptor
370 * so it is OK if devres_destroy() returns -ENOENT.
371 */
372 if (ret == -ENOENT)
373 return;
374 /* Anything else we should warn about */
375 WARN_ON(ret);
376}
377EXPORT_SYMBOL_GPL(devm_gpiod_unhinge);
378
379/**
380 * devm_gpiod_put_array - Resource-managed gpiod_put_array()
381 * @dev: GPIO consumer
382 * @descs: GPIO descriptor array to dispose of
383 *
384 * Dispose of an array of GPIO descriptors obtained with devm_gpiod_get_array().
385 * Normally this function will not be called as the GPIOs will be disposed of
386 * by the resource management code.
387 */
388void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs)
389{
390 WARN_ON(devres_release(dev, devm_gpiod_release_array,
391 devm_gpiod_match_array, &descs));
392}
393EXPORT_SYMBOL_GPL(devm_gpiod_put_array);
394
395
396
397
398static void devm_gpio_release(struct device *dev, void *res)
399{
400 unsigned *gpio = res;
401
402 gpio_free(*gpio);
403}
404
405static int devm_gpio_match(struct device *dev, void *res, void *data)
406{
407 unsigned *this = res, *gpio = data;
408
409 return *this == *gpio;
410}
411
412/**
413 * devm_gpio_request - request a GPIO for a managed device
414 * @dev: device to request the GPIO for
415 * @gpio: GPIO to allocate
416 * @label: the name of the requested GPIO
417 *
418 * Except for the extra @dev argument, this function takes the
419 * same arguments and performs the same function as
420 * gpio_request(). GPIOs requested with this function will be
421 * automatically freed on driver detach.
422 *
423 * If an GPIO allocated with this function needs to be freed
424 * separately, devm_gpio_free() must be used.
425 */
426
427int devm_gpio_request(struct device *dev, unsigned gpio, const char *label)
428{
429 unsigned *dr;
430 int rc;
431
432 dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
433 if (!dr)
434 return -ENOMEM;
435
436 rc = gpio_request(gpio, label);
437 if (rc) {
438 devres_free(dr);
439 return rc;
440 }
441
442 *dr = gpio;
443 devres_add(dev, dr);
444
445 return 0;
446}
447EXPORT_SYMBOL_GPL(devm_gpio_request);
448
449/**
450 * devm_gpio_request_one - request a single GPIO with initial setup
451 * @dev: device to request for
452 * @gpio: the GPIO number
453 * @flags: GPIO configuration as specified by GPIOF_*
454 * @label: a literal description string of this GPIO
455 */
456int devm_gpio_request_one(struct device *dev, unsigned gpio,
457 unsigned long flags, const char *label)
458{
459 unsigned *dr;
460 int rc;
461
462 dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
463 if (!dr)
464 return -ENOMEM;
465
466 rc = gpio_request_one(gpio, flags, label);
467 if (rc) {
468 devres_free(dr);
469 return rc;
470 }
471
472 *dr = gpio;
473 devres_add(dev, dr);
474
475 return 0;
476}
477EXPORT_SYMBOL_GPL(devm_gpio_request_one);
478
479/**
480 * devm_gpio_free - free a GPIO
481 * @dev: device to free GPIO for
482 * @gpio: GPIO to free
483 *
484 * Except for the extra @dev argument, this function takes the
485 * same arguments and performs the same function as gpio_free().
486 * This function instead of gpio_free() should be used to manually
487 * free GPIOs allocated with devm_gpio_request().
488 */
489void devm_gpio_free(struct device *dev, unsigned int gpio)
490{
491
492 WARN_ON(devres_release(dev, devm_gpio_release, devm_gpio_match,
493 &gpio));
494}
495EXPORT_SYMBOL_GPL(devm_gpio_free);