1 /*
2 * drivers/gpio/devres.c - managed gpio resources
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2
6 * as published by the Free Software Foundation.
7 *
8 * You should have received a copy of the GNU General Public License
9 * along with this program; if not, write to the Free Software
10 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
11 *
12 * This file is based on kernel/irq/devres.c
13 *
14 * Copyright (c) 2011 John Crispin <john@phrozen.org>
15 */
16
17 #include <linux/module.h>
18 #include <linux/err.h>
19 #include <linux/gpio.h>
20 #include <linux/gpio/consumer.h>
21 #include <linux/device.h>
22 #include <linux/gfp.h>
23
24 #include "gpiolib.h"
25
devm_gpiod_release(struct device * dev,void * res)26 static void devm_gpiod_release(struct device *dev, void *res)
27 {
28 struct gpio_desc **desc = res;
29
30 gpiod_put(*desc);
31 }
32
devm_gpiod_match(struct device * dev,void * res,void * data)33 static int devm_gpiod_match(struct device *dev, void *res, void *data)
34 {
35 struct gpio_desc **this = res, **gpio = data;
36
37 return *this == *gpio;
38 }
39
devm_gpiod_release_array(struct device * dev,void * res)40 static void devm_gpiod_release_array(struct device *dev, void *res)
41 {
42 struct gpio_descs **descs = res;
43
44 gpiod_put_array(*descs);
45 }
46
devm_gpiod_match_array(struct device * dev,void * res,void * data)47 static int devm_gpiod_match_array(struct device *dev, void *res, void *data)
48 {
49 struct gpio_descs **this = res, **gpios = data;
50
51 return *this == *gpios;
52 }
53
54 /**
55 * devm_gpiod_get - Resource-managed gpiod_get()
56 * @dev: GPIO consumer
57 * @con_id: function within the GPIO consumer
58 * @flags: optional GPIO initialization flags
59 *
60 * Managed gpiod_get(). GPIO descriptors returned from this function are
61 * automatically disposed on driver detach. See gpiod_get() for detailed
62 * information about behavior and return values.
63 */
devm_gpiod_get(struct device * dev,const char * con_id,enum gpiod_flags flags)64 struct gpio_desc *__must_check devm_gpiod_get(struct device *dev,
65 const char *con_id,
66 enum gpiod_flags flags)
67 {
68 return devm_gpiod_get_index(dev, con_id, 0, flags);
69 }
70 EXPORT_SYMBOL(devm_gpiod_get);
71
72 /**
73 * devm_gpiod_get_optional - Resource-managed gpiod_get_optional()
74 * @dev: GPIO consumer
75 * @con_id: function within the GPIO consumer
76 * @flags: optional GPIO initialization flags
77 *
78 * Managed gpiod_get_optional(). GPIO descriptors returned from this function
79 * are automatically disposed on driver detach. See gpiod_get_optional() for
80 * detailed information about behavior and return values.
81 */
devm_gpiod_get_optional(struct device * dev,const char * con_id,enum gpiod_flags flags)82 struct gpio_desc *__must_check devm_gpiod_get_optional(struct device *dev,
83 const char *con_id,
84 enum gpiod_flags flags)
85 {
86 return devm_gpiod_get_index_optional(dev, con_id, 0, flags);
87 }
88 EXPORT_SYMBOL(devm_gpiod_get_optional);
89
90 /**
91 * devm_gpiod_get_index - Resource-managed gpiod_get_index()
92 * @dev: GPIO consumer
93 * @con_id: function within the GPIO consumer
94 * @idx: index of the GPIO to obtain in the consumer
95 * @flags: optional GPIO initialization flags
96 *
97 * Managed gpiod_get_index(). GPIO descriptors returned from this function are
98 * automatically disposed on driver detach. See gpiod_get_index() for detailed
99 * information about behavior and return values.
100 */
devm_gpiod_get_index(struct device * dev,const char * con_id,unsigned int idx,enum gpiod_flags flags)101 struct gpio_desc *__must_check devm_gpiod_get_index(struct device *dev,
102 const char *con_id,
103 unsigned int idx,
104 enum gpiod_flags flags)
105 {
106 struct gpio_desc **dr;
107 struct gpio_desc *desc;
108
109 dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
110 GFP_KERNEL);
111 if (!dr)
112 return ERR_PTR(-ENOMEM);
113
114 desc = gpiod_get_index(dev, con_id, idx, flags);
115 if (IS_ERR(desc)) {
116 devres_free(dr);
117 return desc;
118 }
119
120 *dr = desc;
121 devres_add(dev, dr);
122
123 return desc;
124 }
125 EXPORT_SYMBOL(devm_gpiod_get_index);
126
127 /**
128 * devm_fwnode_get_index_gpiod_from_child - get a GPIO descriptor from a
129 * device's child node
130 * @dev: GPIO consumer
131 * @con_id: function within the GPIO consumer
132 * @index: index of the GPIO to obtain in the consumer
133 * @child: firmware node (child of @dev)
134 * @flags: GPIO initialization flags
135 * @label: label to attach to the requested GPIO
136 *
137 * GPIO descriptors returned from this function are automatically disposed on
138 * driver detach.
139 *
140 * On successful request the GPIO pin is configured in accordance with
141 * provided @flags.
142 */
devm_fwnode_get_index_gpiod_from_child(struct device * dev,const char * con_id,int index,struct fwnode_handle * child,enum gpiod_flags flags,const char * label)143 struct gpio_desc *devm_fwnode_get_index_gpiod_from_child(struct device *dev,
144 const char *con_id, int index,
145 struct fwnode_handle *child,
146 enum gpiod_flags flags,
147 const char *label)
148 {
149 char prop_name[32]; /* 32 is max size of property name */
150 struct gpio_desc **dr;
151 struct gpio_desc *desc;
152 unsigned int i;
153
154 dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
155 GFP_KERNEL);
156 if (!dr)
157 return ERR_PTR(-ENOMEM);
158
159 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
160 if (con_id)
161 snprintf(prop_name, sizeof(prop_name), "%s-%s",
162 con_id, gpio_suffixes[i]);
163 else
164 snprintf(prop_name, sizeof(prop_name), "%s",
165 gpio_suffixes[i]);
166
167 desc = fwnode_get_named_gpiod(child, prop_name, index, flags,
168 label);
169 if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
170 break;
171 }
172 if (IS_ERR(desc)) {
173 devres_free(dr);
174 return desc;
175 }
176
177 *dr = desc;
178 devres_add(dev, dr);
179
180 return desc;
181 }
182 EXPORT_SYMBOL(devm_fwnode_get_index_gpiod_from_child);
183
184 /**
185 * devm_gpiod_get_index_optional - Resource-managed gpiod_get_index_optional()
186 * @dev: GPIO consumer
187 * @con_id: function within the GPIO consumer
188 * @index: index of the GPIO to obtain in the consumer
189 * @flags: optional GPIO initialization flags
190 *
191 * Managed gpiod_get_index_optional(). GPIO descriptors returned from this
192 * function are automatically disposed on driver detach. See
193 * gpiod_get_index_optional() for detailed information about behavior and
194 * return values.
195 */
devm_gpiod_get_index_optional(struct device * dev,const char * con_id,unsigned int index,enum gpiod_flags flags)196 struct gpio_desc *__must_check devm_gpiod_get_index_optional(struct device *dev,
197 const char *con_id,
198 unsigned int index,
199 enum gpiod_flags flags)
200 {
201 struct gpio_desc *desc;
202
203 desc = devm_gpiod_get_index(dev, con_id, index, flags);
204 if (IS_ERR(desc)) {
205 if (PTR_ERR(desc) == -ENOENT)
206 return NULL;
207 }
208
209 return desc;
210 }
211 EXPORT_SYMBOL(devm_gpiod_get_index_optional);
212
213 /**
214 * devm_gpiod_get_array - Resource-managed gpiod_get_array()
215 * @dev: GPIO consumer
216 * @con_id: function within the GPIO consumer
217 * @flags: optional GPIO initialization flags
218 *
219 * Managed gpiod_get_array(). GPIO descriptors returned from this function are
220 * automatically disposed on driver detach. See gpiod_get_array() for detailed
221 * information about behavior and return values.
222 */
devm_gpiod_get_array(struct device * dev,const char * con_id,enum gpiod_flags flags)223 struct gpio_descs *__must_check devm_gpiod_get_array(struct device *dev,
224 const char *con_id,
225 enum gpiod_flags flags)
226 {
227 struct gpio_descs **dr;
228 struct gpio_descs *descs;
229
230 dr = devres_alloc(devm_gpiod_release_array,
231 sizeof(struct gpio_descs *), GFP_KERNEL);
232 if (!dr)
233 return ERR_PTR(-ENOMEM);
234
235 descs = gpiod_get_array(dev, con_id, flags);
236 if (IS_ERR(descs)) {
237 devres_free(dr);
238 return descs;
239 }
240
241 *dr = descs;
242 devres_add(dev, dr);
243
244 return descs;
245 }
246 EXPORT_SYMBOL(devm_gpiod_get_array);
247
248 /**
249 * devm_gpiod_get_array_optional - Resource-managed gpiod_get_array_optional()
250 * @dev: GPIO consumer
251 * @con_id: function within the GPIO consumer
252 * @flags: optional GPIO initialization flags
253 *
254 * Managed gpiod_get_array_optional(). GPIO descriptors returned from this
255 * function are automatically disposed on driver detach.
256 * See gpiod_get_array_optional() for detailed information about behavior and
257 * return values.
258 */
259 struct gpio_descs *__must_check
devm_gpiod_get_array_optional(struct device * dev,const char * con_id,enum gpiod_flags flags)260 devm_gpiod_get_array_optional(struct device *dev, const char *con_id,
261 enum gpiod_flags flags)
262 {
263 struct gpio_descs *descs;
264
265 descs = devm_gpiod_get_array(dev, con_id, flags);
266 if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT))
267 return NULL;
268
269 return descs;
270 }
271 EXPORT_SYMBOL(devm_gpiod_get_array_optional);
272
273 /**
274 * devm_gpiod_put - Resource-managed gpiod_put()
275 * @dev: GPIO consumer
276 * @desc: GPIO descriptor to dispose of
277 *
278 * Dispose of a GPIO descriptor obtained with devm_gpiod_get() or
279 * devm_gpiod_get_index(). Normally this function will not be called as the GPIO
280 * will be disposed of by the resource management code.
281 */
devm_gpiod_put(struct device * dev,struct gpio_desc * desc)282 void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
283 {
284 WARN_ON(devres_release(dev, devm_gpiod_release, devm_gpiod_match,
285 &desc));
286 }
287 EXPORT_SYMBOL(devm_gpiod_put);
288
289 /**
290 * devm_gpiod_put_array - Resource-managed gpiod_put_array()
291 * @dev: GPIO consumer
292 * @descs: GPIO descriptor array to dispose of
293 *
294 * Dispose of an array of GPIO descriptors obtained with devm_gpiod_get_array().
295 * Normally this function will not be called as the GPIOs will be disposed of
296 * by the resource management code.
297 */
devm_gpiod_put_array(struct device * dev,struct gpio_descs * descs)298 void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs)
299 {
300 WARN_ON(devres_release(dev, devm_gpiod_release_array,
301 devm_gpiod_match_array, &descs));
302 }
303 EXPORT_SYMBOL(devm_gpiod_put_array);
304
305
306
307
devm_gpio_release(struct device * dev,void * res)308 static void devm_gpio_release(struct device *dev, void *res)
309 {
310 unsigned *gpio = res;
311
312 gpio_free(*gpio);
313 }
314
devm_gpio_match(struct device * dev,void * res,void * data)315 static int devm_gpio_match(struct device *dev, void *res, void *data)
316 {
317 unsigned *this = res, *gpio = data;
318
319 return *this == *gpio;
320 }
321
322 /**
323 * devm_gpio_request - request a GPIO for a managed device
324 * @dev: device to request the GPIO for
325 * @gpio: GPIO to allocate
326 * @label: the name of the requested GPIO
327 *
328 * Except for the extra @dev argument, this function takes the
329 * same arguments and performs the same function as
330 * gpio_request(). GPIOs requested with this function will be
331 * automatically freed on driver detach.
332 *
333 * If an GPIO allocated with this function needs to be freed
334 * separately, devm_gpio_free() must be used.
335 */
336
devm_gpio_request(struct device * dev,unsigned gpio,const char * label)337 int devm_gpio_request(struct device *dev, unsigned gpio, const char *label)
338 {
339 unsigned *dr;
340 int rc;
341
342 dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
343 if (!dr)
344 return -ENOMEM;
345
346 rc = gpio_request(gpio, label);
347 if (rc) {
348 devres_free(dr);
349 return rc;
350 }
351
352 *dr = gpio;
353 devres_add(dev, dr);
354
355 return 0;
356 }
357 EXPORT_SYMBOL(devm_gpio_request);
358
359 /**
360 * devm_gpio_request_one - request a single GPIO with initial setup
361 * @dev: device to request for
362 * @gpio: the GPIO number
363 * @flags: GPIO configuration as specified by GPIOF_*
364 * @label: a literal description string of this GPIO
365 */
devm_gpio_request_one(struct device * dev,unsigned gpio,unsigned long flags,const char * label)366 int devm_gpio_request_one(struct device *dev, unsigned gpio,
367 unsigned long flags, const char *label)
368 {
369 unsigned *dr;
370 int rc;
371
372 dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
373 if (!dr)
374 return -ENOMEM;
375
376 rc = gpio_request_one(gpio, flags, label);
377 if (rc) {
378 devres_free(dr);
379 return rc;
380 }
381
382 *dr = gpio;
383 devres_add(dev, dr);
384
385 return 0;
386 }
387 EXPORT_SYMBOL(devm_gpio_request_one);
388
389 /**
390 * devm_gpio_free - free a GPIO
391 * @dev: device to free GPIO for
392 * @gpio: GPIO to free
393 *
394 * Except for the extra @dev argument, this function takes the
395 * same arguments and performs the same function as gpio_free().
396 * This function instead of gpio_free() should be used to manually
397 * free GPIOs allocated with devm_gpio_request().
398 */
devm_gpio_free(struct device * dev,unsigned int gpio)399 void devm_gpio_free(struct device *dev, unsigned int gpio)
400 {
401
402 WARN_ON(devres_release(dev, devm_gpio_release, devm_gpio_match,
403 &gpio));
404 }
405 EXPORT_SYMBOL(devm_gpio_free);
406