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: *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: *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, idx: 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, index: 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(ptr: 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, release: devm_gpiod_release,
113 match: devm_gpiod_match, match_data: &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(error: -ENOMEM);
123 }
124
125 *dr = desc;
126 devres_add(dev, res: dr);
127
128 return desc;
129}
130EXPORT_SYMBOL_GPL(devm_gpiod_get_index);
131
132/**
133 * devm_fwnode_gpiod_get_index - get a GPIO descriptor from a given node
134 * @dev: GPIO consumer
135 * @fwnode: firmware node containing GPIO reference
136 * @con_id: function within the GPIO consumer
137 * @index: index of the GPIO to obtain in the consumer
138 * @flags: GPIO initialization flags
139 * @label: label to attach to the requested GPIO
140 *
141 * GPIO descriptors returned from this function are automatically disposed on
142 * driver detach.
143 *
144 * On successful request the GPIO pin is configured in accordance with
145 * provided @flags.
146 */
147struct gpio_desc *devm_fwnode_gpiod_get_index(struct device *dev,
148 struct fwnode_handle *fwnode,
149 const char *con_id, int index,
150 enum gpiod_flags flags,
151 const char *label)
152{
153 struct gpio_desc **dr;
154 struct gpio_desc *desc;
155
156 dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
157 GFP_KERNEL);
158 if (!dr)
159 return ERR_PTR(error: -ENOMEM);
160
161 desc = fwnode_gpiod_get_index(fwnode, con_id, index, flags, label);
162 if (IS_ERR(ptr: desc)) {
163 devres_free(res: dr);
164 return desc;
165 }
166
167 *dr = desc;
168 devres_add(dev, res: dr);
169
170 return desc;
171}
172EXPORT_SYMBOL_GPL(devm_fwnode_gpiod_get_index);
173
174/**
175 * devm_gpiod_get_index_optional - Resource-managed gpiod_get_index_optional()
176 * @dev: GPIO consumer
177 * @con_id: function within the GPIO consumer
178 * @index: index of the GPIO to obtain in the consumer
179 * @flags: optional GPIO initialization flags
180 *
181 * Managed gpiod_get_index_optional(). GPIO descriptors returned from this
182 * function are automatically disposed on driver detach. See
183 * gpiod_get_index_optional() for detailed information about behavior and
184 * return values.
185 */
186struct gpio_desc *__must_check devm_gpiod_get_index_optional(struct device *dev,
187 const char *con_id,
188 unsigned int index,
189 enum gpiod_flags flags)
190{
191 struct gpio_desc *desc;
192
193 desc = devm_gpiod_get_index(dev, con_id, index, flags);
194 if (gpiod_not_found(desc))
195 return NULL;
196
197 return desc;
198}
199EXPORT_SYMBOL_GPL(devm_gpiod_get_index_optional);
200
201/**
202 * devm_gpiod_get_array - Resource-managed gpiod_get_array()
203 * @dev: GPIO consumer
204 * @con_id: function within the GPIO consumer
205 * @flags: optional GPIO initialization flags
206 *
207 * Managed gpiod_get_array(). GPIO descriptors returned from this function are
208 * automatically disposed on driver detach. See gpiod_get_array() for detailed
209 * information about behavior and return values.
210 */
211struct gpio_descs *__must_check devm_gpiod_get_array(struct device *dev,
212 const char *con_id,
213 enum gpiod_flags flags)
214{
215 struct gpio_descs **dr;
216 struct gpio_descs *descs;
217
218 dr = devres_alloc(devm_gpiod_release_array,
219 sizeof(struct gpio_descs *), GFP_KERNEL);
220 if (!dr)
221 return ERR_PTR(error: -ENOMEM);
222
223 descs = gpiod_get_array(dev, con_id, flags);
224 if (IS_ERR(ptr: descs)) {
225 devres_free(res: dr);
226 return descs;
227 }
228
229 *dr = descs;
230 devres_add(dev, res: dr);
231
232 return descs;
233}
234EXPORT_SYMBOL_GPL(devm_gpiod_get_array);
235
236/**
237 * devm_gpiod_get_array_optional - Resource-managed gpiod_get_array_optional()
238 * @dev: GPIO consumer
239 * @con_id: function within the GPIO consumer
240 * @flags: optional GPIO initialization flags
241 *
242 * Managed gpiod_get_array_optional(). GPIO descriptors returned from this
243 * function are automatically disposed on driver detach.
244 * See gpiod_get_array_optional() for detailed information about behavior and
245 * return values.
246 */
247struct gpio_descs *__must_check
248devm_gpiod_get_array_optional(struct device *dev, const char *con_id,
249 enum gpiod_flags flags)
250{
251 struct gpio_descs *descs;
252
253 descs = devm_gpiod_get_array(dev, con_id, flags);
254 if (gpiod_not_found(descs))
255 return NULL;
256
257 return descs;
258}
259EXPORT_SYMBOL_GPL(devm_gpiod_get_array_optional);
260
261/**
262 * devm_gpiod_put - Resource-managed gpiod_put()
263 * @dev: GPIO consumer
264 * @desc: GPIO descriptor to dispose of
265 *
266 * Dispose of a GPIO descriptor obtained with devm_gpiod_get() or
267 * devm_gpiod_get_index(). Normally this function will not be called as the GPIO
268 * will be disposed of by the resource management code.
269 */
270void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
271{
272 WARN_ON(devres_release(dev, devm_gpiod_release, devm_gpiod_match,
273 &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 * Remove resource management from a GPIO descriptor. This is needed when
283 * you want to hand over lifecycle management of a descriptor to another
284 * mechanism.
285 */
286
287void devm_gpiod_unhinge(struct device *dev, struct gpio_desc *desc)
288{
289 int ret;
290
291 if (IS_ERR_OR_NULL(ptr: desc))
292 return;
293 ret = devres_destroy(dev, release: devm_gpiod_release,
294 match: devm_gpiod_match, match_data: &desc);
295 /*
296 * If the GPIO descriptor is requested as nonexclusive, we
297 * may call this function several times on the same descriptor
298 * so it is OK if devres_destroy() returns -ENOENT.
299 */
300 if (ret == -ENOENT)
301 return;
302 /* Anything else we should warn about */
303 WARN_ON(ret);
304}
305EXPORT_SYMBOL_GPL(devm_gpiod_unhinge);
306
307/**
308 * devm_gpiod_put_array - Resource-managed gpiod_put_array()
309 * @dev: GPIO consumer
310 * @descs: GPIO descriptor array to dispose of
311 *
312 * Dispose of an array of GPIO descriptors obtained with devm_gpiod_get_array().
313 * Normally this function will not be called as the GPIOs will be disposed of
314 * by the resource management code.
315 */
316void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs)
317{
318 WARN_ON(devres_release(dev, devm_gpiod_release_array,
319 devm_gpiod_match_array, &descs));
320}
321EXPORT_SYMBOL_GPL(devm_gpiod_put_array);
322
323static void devm_gpio_release(struct device *dev, void *res)
324{
325 unsigned *gpio = res;
326
327 gpio_free(gpio: *gpio);
328}
329
330/**
331 * devm_gpio_request - request a GPIO for a managed device
332 * @dev: device to request the GPIO for
333 * @gpio: GPIO to allocate
334 * @label: the name of the requested GPIO
335 *
336 * Except for the extra @dev argument, this function takes the
337 * same arguments and performs the same function as
338 * gpio_request(). GPIOs requested with this function will be
339 * automatically freed on driver detach.
340 */
341int devm_gpio_request(struct device *dev, unsigned gpio, const char *label)
342{
343 unsigned *dr;
344 int rc;
345
346 dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
347 if (!dr)
348 return -ENOMEM;
349
350 rc = gpio_request(gpio, label);
351 if (rc) {
352 devres_free(res: dr);
353 return rc;
354 }
355
356 *dr = gpio;
357 devres_add(dev, res: dr);
358
359 return 0;
360}
361EXPORT_SYMBOL_GPL(devm_gpio_request);
362
363/**
364 * devm_gpio_request_one - request a single GPIO with initial setup
365 * @dev: device to request for
366 * @gpio: the GPIO number
367 * @flags: GPIO configuration as specified by GPIOF_*
368 * @label: a literal description string of this GPIO
369 */
370int devm_gpio_request_one(struct device *dev, unsigned gpio,
371 unsigned long flags, const char *label)
372{
373 unsigned *dr;
374 int rc;
375
376 dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
377 if (!dr)
378 return -ENOMEM;
379
380 rc = gpio_request_one(gpio, flags, label);
381 if (rc) {
382 devres_free(res: dr);
383 return rc;
384 }
385
386 *dr = gpio;
387 devres_add(dev, res: dr);
388
389 return 0;
390}
391EXPORT_SYMBOL_GPL(devm_gpio_request_one);
392
393static void devm_gpio_chip_release(void *data)
394{
395 struct gpio_chip *gc = data;
396
397 gpiochip_remove(gc);
398}
399
400/**
401 * devm_gpiochip_add_data_with_key() - Resource managed gpiochip_add_data_with_key()
402 * @dev: pointer to the device that gpio_chip belongs to.
403 * @gc: the GPIO chip to register
404 * @data: driver-private data associated with this chip
405 * @lock_key: lockdep class for IRQ lock
406 * @request_key: lockdep class for IRQ request
407 *
408 * Context: potentially before irqs will work
409 *
410 * The gpio chip automatically be released when the device is unbound.
411 *
412 * Returns:
413 * A negative errno if the chip can't be registered, such as because the
414 * gc->base is invalid or already associated with a different chip.
415 * Otherwise it returns zero as a success code.
416 */
417int devm_gpiochip_add_data_with_key(struct device *dev, struct gpio_chip *gc, void *data,
418 struct lock_class_key *lock_key,
419 struct lock_class_key *request_key)
420{
421 int ret;
422
423 ret = gpiochip_add_data_with_key(gc, data, lock_key, request_key);
424 if (ret < 0)
425 return ret;
426
427 return devm_add_action_or_reset(dev, devm_gpio_chip_release, gc);
428}
429EXPORT_SYMBOL_GPL(devm_gpiochip_add_data_with_key);
430

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