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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/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_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 */
202struct 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}
227EXPORT_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 */
241struct 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 (IS_ERR(desc)) {
250 if (PTR_ERR(desc) == -ENOENT)
251 return NULL;
252 }
253
254 return desc;
255}
256EXPORT_SYMBOL_GPL(devm_gpiod_get_index_optional);
257
258/**
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
263 *
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.
267 */
268struct gpio_descs *__must_check devm_gpiod_get_array(struct device *dev,
269 const char *con_id,
270 enum gpiod_flags flags)
271{
272 struct gpio_descs **dr;
273 struct gpio_descs *descs;
274
275 dr = devres_alloc(devm_gpiod_release_array,
276 sizeof(struct gpio_descs *), GFP_KERNEL);
277 if (!dr)
278 return ERR_PTR(-ENOMEM);
279
280 descs = gpiod_get_array(dev, con_id, flags);
281 if (IS_ERR(descs)) {
282 devres_free(dr);
283 return descs;
284 }
285
286 *dr = descs;
287 devres_add(dev, dr);
288
289 return descs;
290}
291EXPORT_SYMBOL_GPL(devm_gpiod_get_array);
292
293/**
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
298 *
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
302 * return values.
303 */
304struct gpio_descs *__must_check
305devm_gpiod_get_array_optional(struct device *dev, const char *con_id,
306 enum gpiod_flags flags)
307{
308 struct gpio_descs *descs;
309
310 descs = devm_gpiod_get_array(dev, con_id, flags);
311 if (PTR_ERR(descs) == -ENOENT)
312 return NULL;
313
314 return descs;
315}
316EXPORT_SYMBOL_GPL(devm_gpiod_get_array_optional);
317
318/**
319 * devm_gpiod_put - Resource-managed gpiod_put()
320 * @dev: GPIO consumer
321 * @desc: GPIO descriptor to dispose of
322 *
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.
326 */
327void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
328{
329 WARN_ON(devres_release(dev, devm_gpiod_release, devm_gpiod_match,
330 &desc));
331}
332EXPORT_SYMBOL_GPL(devm_gpiod_put);
333
334/**
335 * devm_gpiod_unhinge - Remove resource management from a gpio descriptor
336 * @dev: GPIO consumer
337 * @desc: GPIO descriptor to remove resource management from
338 *
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
341 * mechanism.
342 */
343
344void devm_gpiod_unhinge(struct device *dev, struct gpio_desc *desc)
345{
346 int ret;
347
348 if (IS_ERR_OR_NULL(desc))
349 return;
350 ret = devres_destroy(dev, devm_gpiod_release,
351 devm_gpiod_match, &desc);
352 /*
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.
356 */
357 if (ret == -ENOENT)
358 return;
359 /* Anything else we should warn about */
360 WARN_ON(ret);
361}
362EXPORT_SYMBOL_GPL(devm_gpiod_unhinge);
363
364/**
365 * devm_gpiod_put_array - Resource-managed gpiod_put_array()
366 * @dev: GPIO consumer
367 * @descs: GPIO descriptor array to dispose of
368 *
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.
372 */
373void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs)
374{
375 WARN_ON(devres_release(dev, devm_gpiod_release_array,
376 devm_gpiod_match_array, &descs));
377}
378EXPORT_SYMBOL_GPL(devm_gpiod_put_array);
379
380
381
382
383static void devm_gpio_release(struct device *dev, void *res)
384{
385 unsigned *gpio = res;
386
387 gpio_free(*gpio);
388}
389
390static int devm_gpio_match(struct device *dev, void *res, void *data)
391{
392 unsigned *this = res, *gpio = data;
393
394 return *this == *gpio;
395}
396
397/**
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
402 *
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.
407 *
408 * If an GPIO allocated with this function needs to be freed
409 * separately, devm_gpio_free() must be used.
410 */
411
412int devm_gpio_request(struct device *dev, unsigned gpio, const char *label)
413{
414 unsigned *dr;
415 int rc;
416
417 dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
418 if (!dr)
419 return -ENOMEM;
420
421 rc = gpio_request(gpio, label);
422 if (rc) {
423 devres_free(dr);
424 return rc;
425 }
426
427 *dr = gpio;
428 devres_add(dev, dr);
429
430 return 0;
431}
432EXPORT_SYMBOL_GPL(devm_gpio_request);
433
434/**
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
440 */
441int devm_gpio_request_one(struct device *dev, unsigned gpio,
442 unsigned long flags, const char *label)
443{
444 unsigned *dr;
445 int rc;
446
447 dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
448 if (!dr)
449 return -ENOMEM;
450
451 rc = gpio_request_one(gpio, flags, label);
452 if (rc) {
453 devres_free(dr);
454 return rc;
455 }
456
457 *dr = gpio;
458 devres_add(dev, dr);
459
460 return 0;
461}
462EXPORT_SYMBOL_GPL(devm_gpio_request_one);
463
464/**
465 * devm_gpio_free - free a GPIO
466 * @dev: device to free GPIO for
467 * @gpio: GPIO to free
468 *
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().
473 */
474void devm_gpio_free(struct device *dev, unsigned int gpio)
475{
476
477 WARN_ON(devres_release(dev, devm_gpio_release, devm_gpio_match,
478 &gpio));
479}
480EXPORT_SYMBOL_GPL(devm_gpio_free);
481
482static void devm_gpio_chip_release(struct device *dev, void *res)
483{
484 struct gpio_chip *gc = *(struct gpio_chip **)res;
485
486 gpiochip_remove(gc);
487}
488
489/**
490 * devm_gpiochip_add_data_with_key() - Resource managed gpiochip_add_data_with_key()
491 * @dev: pointer to the device that gpio_chip belongs to.
492 * @gc: the GPIO chip to register
493 * @data: driver-private data associated with this chip
494 * @lock_key: lockdep class for IRQ lock
495 * @request_key: lockdep class for IRQ request
496 *
497 * Context: potentially before irqs will work
498 *
499 * The gpio chip automatically be released when the device is unbound.
500 *
501 * Returns:
502 * A negative errno if the chip can't be registered, such as because the
503 * gc->base is invalid or already associated with a different chip.
504 * Otherwise it returns zero as a success code.
505 */
506int devm_gpiochip_add_data_with_key(struct device *dev, struct gpio_chip *gc, void *data,
507 struct lock_class_key *lock_key,
508 struct lock_class_key *request_key)
509{
510 struct gpio_chip **ptr;
511 int ret;
512
513 ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr),
514 GFP_KERNEL);
515 if (!ptr)
516 return -ENOMEM;
517
518 ret = gpiochip_add_data_with_key(gc, data, lock_key, request_key);
519 if (ret < 0) {
520 devres_free(ptr);
521 return ret;
522 }
523
524 *ptr = gc;
525 devres_add(dev, ptr);
526
527 return 0;
528}
529EXPORT_SYMBOL_GPL(devm_gpiochip_add_data_with_key);