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
devm_gpiod_release(struct device * dev,void * res)18 static void devm_gpiod_release(struct device *dev, void *res)
19 {
20 struct gpio_desc **desc = res;
21
22 gpiod_put(*desc);
23 }
24
devm_gpiod_match(struct device * dev,void * res,void * data)25 static 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
devm_gpiod_release_array(struct device * dev,void * res)32 static 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
devm_gpiod_match_array(struct device * dev,void * res,void * data)39 static 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 */
devm_gpiod_get(struct device * dev,const char * con_id,enum gpiod_flags flags)56 struct 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 }
62 EXPORT_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 */
devm_gpiod_get_optional(struct device * dev,const char * con_id,enum gpiod_flags flags)74 struct 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 }
80 EXPORT_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 */
devm_gpiod_get_index(struct device * dev,const char * con_id,unsigned int idx,enum gpiod_flags flags)93 struct 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 }
130 EXPORT_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 */
devm_gpiod_get_from_of_node(struct device * dev,const struct device_node * node,const char * propname,int index,enum gpiod_flags dflags,const char * label)147 struct gpio_desc *devm_gpiod_get_from_of_node(struct device *dev,
148 const 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 }
185 EXPORT_SYMBOL_GPL(devm_gpiod_get_from_of_node);
186
187 /**
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
195 *
196 * GPIO descriptors returned from this function are automatically disposed on
197 * driver detach.
198 *
199 * On successful request the GPIO pin is configured in accordance with
200 * provided @flags.
201 */
devm_fwnode_gpiod_get_index(struct device * dev,struct fwnode_handle * fwnode,const char * con_id,int index,enum gpiod_flags flags,const char * label)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,
206 const char *label)
207 {
208 struct gpio_desc **dr;
209 struct gpio_desc *desc;
210
211 dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
212 GFP_KERNEL);
213 if (!dr)
214 return ERR_PTR(-ENOMEM);
215
216 desc = fwnode_gpiod_get_index(fwnode, con_id, index, flags, label);
217 if (IS_ERR(desc)) {
218 devres_free(dr);
219 return desc;
220 }
221
222 *dr = desc;
223 devres_add(dev, dr);
224
225 return desc;
226 }
227 EXPORT_SYMBOL_GPL(devm_fwnode_gpiod_get_index);
228
229 /**
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
235 *
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
239 * return values.
240 */
devm_gpiod_get_index_optional(struct device * dev,const char * con_id,unsigned int index,enum gpiod_flags flags)241 struct gpio_desc *__must_check devm_gpiod_get_index_optional(struct device *dev,
242 const char *con_id,
243 unsigned int index,
244 enum gpiod_flags flags)
245 {
246 struct gpio_desc *desc;
247
248 desc = devm_gpiod_get_index(dev, con_id, index, flags);
249 if (gpiod_not_found(desc))
250 return NULL;
251
252 return desc;
253 }
254 EXPORT_SYMBOL_GPL(devm_gpiod_get_index_optional);
255
256 /**
257 * devm_gpiod_get_array - Resource-managed gpiod_get_array()
258 * @dev: GPIO consumer
259 * @con_id: function within the GPIO consumer
260 * @flags: optional GPIO initialization flags
261 *
262 * Managed gpiod_get_array(). GPIO descriptors returned from this function are
263 * automatically disposed on driver detach. See gpiod_get_array() for detailed
264 * information about behavior and return values.
265 */
devm_gpiod_get_array(struct device * dev,const char * con_id,enum gpiod_flags flags)266 struct gpio_descs *__must_check devm_gpiod_get_array(struct device *dev,
267 const char *con_id,
268 enum gpiod_flags flags)
269 {
270 struct gpio_descs **dr;
271 struct gpio_descs *descs;
272
273 dr = devres_alloc(devm_gpiod_release_array,
274 sizeof(struct gpio_descs *), GFP_KERNEL);
275 if (!dr)
276 return ERR_PTR(-ENOMEM);
277
278 descs = gpiod_get_array(dev, con_id, flags);
279 if (IS_ERR(descs)) {
280 devres_free(dr);
281 return descs;
282 }
283
284 *dr = descs;
285 devres_add(dev, dr);
286
287 return descs;
288 }
289 EXPORT_SYMBOL_GPL(devm_gpiod_get_array);
290
291 /**
292 * devm_gpiod_get_array_optional - Resource-managed gpiod_get_array_optional()
293 * @dev: GPIO consumer
294 * @con_id: function within the GPIO consumer
295 * @flags: optional GPIO initialization flags
296 *
297 * Managed gpiod_get_array_optional(). GPIO descriptors returned from this
298 * function are automatically disposed on driver detach.
299 * See gpiod_get_array_optional() for detailed information about behavior and
300 * return values.
301 */
302 struct gpio_descs *__must_check
devm_gpiod_get_array_optional(struct device * dev,const char * con_id,enum gpiod_flags flags)303 devm_gpiod_get_array_optional(struct device *dev, const char *con_id,
304 enum gpiod_flags flags)
305 {
306 struct gpio_descs *descs;
307
308 descs = devm_gpiod_get_array(dev, con_id, flags);
309 if (gpiod_not_found(descs))
310 return NULL;
311
312 return descs;
313 }
314 EXPORT_SYMBOL_GPL(devm_gpiod_get_array_optional);
315
316 /**
317 * devm_gpiod_put - Resource-managed gpiod_put()
318 * @dev: GPIO consumer
319 * @desc: GPIO descriptor to dispose of
320 *
321 * Dispose of a GPIO descriptor obtained with devm_gpiod_get() or
322 * devm_gpiod_get_index(). Normally this function will not be called as the GPIO
323 * will be disposed of by the resource management code.
324 */
devm_gpiod_put(struct device * dev,struct gpio_desc * desc)325 void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
326 {
327 WARN_ON(devres_release(dev, devm_gpiod_release, devm_gpiod_match,
328 &desc));
329 }
330 EXPORT_SYMBOL_GPL(devm_gpiod_put);
331
332 /**
333 * devm_gpiod_unhinge - Remove resource management from a gpio descriptor
334 * @dev: GPIO consumer
335 * @desc: GPIO descriptor to remove resource management from
336 *
337 * Remove resource management from a GPIO descriptor. This is needed when
338 * you want to hand over lifecycle management of a descriptor to another
339 * mechanism.
340 */
341
devm_gpiod_unhinge(struct device * dev,struct gpio_desc * desc)342 void devm_gpiod_unhinge(struct device *dev, struct gpio_desc *desc)
343 {
344 int ret;
345
346 if (IS_ERR_OR_NULL(desc))
347 return;
348 ret = devres_destroy(dev, devm_gpiod_release,
349 devm_gpiod_match, &desc);
350 /*
351 * If the GPIO descriptor is requested as nonexclusive, we
352 * may call this function several times on the same descriptor
353 * so it is OK if devres_destroy() returns -ENOENT.
354 */
355 if (ret == -ENOENT)
356 return;
357 /* Anything else we should warn about */
358 WARN_ON(ret);
359 }
360 EXPORT_SYMBOL_GPL(devm_gpiod_unhinge);
361
362 /**
363 * devm_gpiod_put_array - Resource-managed gpiod_put_array()
364 * @dev: GPIO consumer
365 * @descs: GPIO descriptor array to dispose of
366 *
367 * Dispose of an array of GPIO descriptors obtained with devm_gpiod_get_array().
368 * Normally this function will not be called as the GPIOs will be disposed of
369 * by the resource management code.
370 */
devm_gpiod_put_array(struct device * dev,struct gpio_descs * descs)371 void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs)
372 {
373 WARN_ON(devres_release(dev, devm_gpiod_release_array,
374 devm_gpiod_match_array, &descs));
375 }
376 EXPORT_SYMBOL_GPL(devm_gpiod_put_array);
377
378
379
380
devm_gpio_release(struct device * dev,void * res)381 static void devm_gpio_release(struct device *dev, void *res)
382 {
383 unsigned *gpio = res;
384
385 gpio_free(*gpio);
386 }
387
devm_gpio_match(struct device * dev,void * res,void * data)388 static int devm_gpio_match(struct device *dev, void *res, void *data)
389 {
390 unsigned *this = res, *gpio = data;
391
392 return *this == *gpio;
393 }
394
395 /**
396 * devm_gpio_request - request a GPIO for a managed device
397 * @dev: device to request the GPIO for
398 * @gpio: GPIO to allocate
399 * @label: the name of the requested GPIO
400 *
401 * Except for the extra @dev argument, this function takes the
402 * same arguments and performs the same function as
403 * gpio_request(). GPIOs requested with this function will be
404 * automatically freed on driver detach.
405 *
406 * If an GPIO allocated with this function needs to be freed
407 * separately, devm_gpio_free() must be used.
408 */
409
devm_gpio_request(struct device * dev,unsigned gpio,const char * label)410 int devm_gpio_request(struct device *dev, unsigned gpio, const char *label)
411 {
412 unsigned *dr;
413 int rc;
414
415 dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
416 if (!dr)
417 return -ENOMEM;
418
419 rc = gpio_request(gpio, label);
420 if (rc) {
421 devres_free(dr);
422 return rc;
423 }
424
425 *dr = gpio;
426 devres_add(dev, dr);
427
428 return 0;
429 }
430 EXPORT_SYMBOL_GPL(devm_gpio_request);
431
432 /**
433 * devm_gpio_request_one - request a single GPIO with initial setup
434 * @dev: device to request for
435 * @gpio: the GPIO number
436 * @flags: GPIO configuration as specified by GPIOF_*
437 * @label: a literal description string of this GPIO
438 */
devm_gpio_request_one(struct device * dev,unsigned gpio,unsigned long flags,const char * label)439 int devm_gpio_request_one(struct device *dev, unsigned gpio,
440 unsigned long flags, const char *label)
441 {
442 unsigned *dr;
443 int rc;
444
445 dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
446 if (!dr)
447 return -ENOMEM;
448
449 rc = gpio_request_one(gpio, flags, label);
450 if (rc) {
451 devres_free(dr);
452 return rc;
453 }
454
455 *dr = gpio;
456 devres_add(dev, dr);
457
458 return 0;
459 }
460 EXPORT_SYMBOL_GPL(devm_gpio_request_one);
461
462 /**
463 * devm_gpio_free - free a GPIO
464 * @dev: device to free GPIO for
465 * @gpio: GPIO to free
466 *
467 * Except for the extra @dev argument, this function takes the
468 * same arguments and performs the same function as gpio_free().
469 * This function instead of gpio_free() should be used to manually
470 * free GPIOs allocated with devm_gpio_request().
471 */
devm_gpio_free(struct device * dev,unsigned int gpio)472 void devm_gpio_free(struct device *dev, unsigned int gpio)
473 {
474
475 WARN_ON(devres_release(dev, devm_gpio_release, devm_gpio_match,
476 &gpio));
477 }
478 EXPORT_SYMBOL_GPL(devm_gpio_free);
479
devm_gpio_chip_release(void * data)480 static void devm_gpio_chip_release(void *data)
481 {
482 struct gpio_chip *gc = data;
483
484 gpiochip_remove(gc);
485 }
486
487 /**
488 * devm_gpiochip_add_data_with_key() - Resource managed gpiochip_add_data_with_key()
489 * @dev: pointer to the device that gpio_chip belongs to.
490 * @gc: the GPIO chip to register
491 * @data: driver-private data associated with this chip
492 * @lock_key: lockdep class for IRQ lock
493 * @request_key: lockdep class for IRQ request
494 *
495 * Context: potentially before irqs will work
496 *
497 * The gpio chip automatically be released when the device is unbound.
498 *
499 * Returns:
500 * A negative errno if the chip can't be registered, such as because the
501 * gc->base is invalid or already associated with a different chip.
502 * Otherwise it returns zero as a success code.
503 */
devm_gpiochip_add_data_with_key(struct device * dev,struct gpio_chip * gc,void * data,struct lock_class_key * lock_key,struct lock_class_key * request_key)504 int devm_gpiochip_add_data_with_key(struct device *dev, struct gpio_chip *gc, void *data,
505 struct lock_class_key *lock_key,
506 struct lock_class_key *request_key)
507 {
508 int ret;
509
510 ret = gpiochip_add_data_with_key(gc, data, lock_key, request_key);
511 if (ret < 0)
512 return ret;
513
514 return devm_add_action_or_reset(dev, devm_gpio_chip_release, gc);
515 }
516 EXPORT_SYMBOL_GPL(devm_gpiochip_add_data_with_key);
517