aboutsummaryrefslogtreecommitdiff
path: root/drivers/gpio/devres.c
blob: b760cbbb41d824908e1532f384de8c447b16b603 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
/*
 * drivers/gpio/devres.c - managed gpio resources
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * This file is based on kernel/irq/devres.c
 *
 * Copyright (c) 2011 John Crispin <blogic@openwrt.org>
 */

#include <linux/module.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/device.h>
#include <linux/gfp.h>

static void devm_gpiod_release(struct device *dev, void *res)
{
	struct gpio_desc **desc = res;

	gpiod_put(*desc);
}

static int devm_gpiod_match(struct device *dev, void *res, void *data)
{
	struct gpio_desc **this = res, **gpio = data;

	return *this == *gpio;
}

static void devm_gpiod_release_array(struct device *dev, void *res)
{
	struct gpio_descs **descs = res;

	gpiod_put_array(*descs);
}

static int devm_gpiod_match_array(struct device *dev, void *res, void *data)
{
	struct gpio_descs **this = res, **gpios = data;

	return *this == *gpios;
}

/**
 * devm_gpiod_get - Resource-managed gpiod_get()
 * @dev:	GPIO consumer
 * @con_id:	function within the GPIO consumer
 * @flags:	optional GPIO initialization flags
 *
 * Managed gpiod_get(). GPIO descriptors returned from this function are
 * automatically disposed on driver detach. See gpiod_get() for detailed
 * information about behavior and return values.
 */
struct gpio_desc *__must_check devm_gpiod_get(struct device *dev,
					      const char *con_id,
					      enum gpiod_flags flags)
{
	return devm_gpiod_get_index(dev, con_id, 0, flags);
}
EXPORT_SYMBOL(devm_gpiod_get);

/**
 * devm_gpiod_get_optional - Resource-managed gpiod_get_optional()
 * @dev: GPIO consumer
 * @con_id: function within the GPIO consumer
 * @flags: optional GPIO initialization flags
 *
 * Managed gpiod_get_optional(). GPIO descriptors returned from this function
 * are automatically disposed on driver detach. See gpiod_get_optional() for
 * detailed information about behavior and return values.
 */
struct gpio_desc *__must_check devm_gpiod_get_optional(struct device *dev,
						       const char *con_id,
						       enum gpiod_flags flags)
{
	return devm_gpiod_get_index_optional(dev, con_id, 0, flags);
}
EXPORT_SYMBOL(devm_gpiod_get_optional);

/**
 * devm_gpiod_get_index - Resource-managed gpiod_get_index()
 * @dev:	GPIO consumer
 * @con_id:	function within the GPIO consumer
 * @idx:	index of the GPIO to obtain in the consumer
 * @flags:	optional GPIO initialization flags
 *
 * Managed gpiod_get_index(). GPIO descriptors returned from this function are
 * automatically disposed on driver detach. See gpiod_get_index() for detailed
 * information about behavior and return values.
 */
struct gpio_desc *__must_check devm_gpiod_get_index(struct device *dev,
						    const char *con_id,
						    unsigned int idx,
						    enum gpiod_flags flags)
{
	struct gpio_desc **dr;
	struct gpio_desc *desc;

	dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
			  GFP_KERNEL);
	if (!dr)
		return ERR_PTR(-ENOMEM);

	desc = gpiod_get_index(dev, con_id, idx, flags);
	if (IS_ERR(desc)) {
		devres_free(dr);
		return desc;
	}

	*dr = desc;
	devres_add(dev, dr);

	return desc;
}
EXPORT_SYMBOL(devm_gpiod_get_index);

/**
 * devm_get_gpiod_from_child - get a GPIO descriptor from a device's child node
 * @dev:	GPIO consumer
 * @con_id:	function within the GPIO consumer
 * @child:	firmware node (child of @dev)
 *
 * GPIO descriptors returned from this function are automatically disposed on
 * driver detach.
 */
struct gpio_desc *devm_get_gpiod_from_child(struct device *dev,
					    const char *con_id,
					    struct fwnode_handle *child)
{
	static const char * const suffixes[] = { "gpios", "gpio" };
	char prop_name[32]; /* 32 is max size of property name */
	struct gpio_desc **dr;
	struct gpio_desc *desc;
	unsigned int i;

	dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *),
			  GFP_KERNEL);
	if (!dr)
		return ERR_PTR(-ENOMEM);

	for (i = 0; i < ARRAY_SIZE(suffixes); i++) {
		if (con_id)
			snprintf(prop_name, sizeof(prop_name), "%s-%s",
					    con_id, suffixes[i]);
		else
			snprintf(prop_name, sizeof(prop_name), "%s",
							       suffixes[i]);

		desc = fwnode_get_named_gpiod(child, prop_name);
		if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
			break;
	}
	if (IS_ERR(desc)) {
		devres_free(dr);
		return desc;
	}

	*dr = desc;
	devres_add(dev, dr);

	return desc;
}
EXPORT_SYMBOL(devm_get_gpiod_from_child);

/**
 * devm_gpiod_get_index_optional - Resource-managed gpiod_get_index_optional()
 * @dev: GPIO consumer
 * @con_id: function within the GPIO consumer
 * @index: index of the GPIO to obtain in the consumer
 * @flags: optional GPIO initialization flags
 *
 * Managed gpiod_get_index_optional(). GPIO descriptors returned from this
 * function are automatically disposed on driver detach. See
 * gpiod_get_index_optional() for detailed information about behavior and
 * return values.
 */
struct gpio_desc *__must_check devm_gpiod_get_index_optional(struct device *dev,
							     const char *con_id,
							     unsigned int index,
							     enum gpiod_flags flags)
{
	struct gpio_desc *desc;

	desc = devm_gpiod_get_index(dev, con_id, index, flags);
	if (IS_ERR(desc)) {
		if (PTR_ERR(desc) == -ENOENT)
			return NULL;
	}

	return desc;
}
EXPORT_SYMBOL(devm_gpiod_get_index_optional);

/**
 * devm_gpiod_get_array - Resource-managed gpiod_get_array()
 * @dev:	GPIO consumer
 * @con_id:	function within the GPIO consumer
 * @flags:	optional GPIO initialization flags
 *
 * Managed gpiod_get_array(). GPIO descriptors returned from this function are
 * automatically disposed on driver detach. See gpiod_get_array() for detailed
 * information about behavior and return values.
 */
struct gpio_descs *__must_check devm_gpiod_get_array(struct device *dev,
						     const char *con_id,
						     enum gpiod_flags flags)
{
	struct gpio_descs **dr;
	struct gpio_descs *descs;

	dr = devres_alloc(devm_gpiod_release_array,
			  sizeof(struct gpio_descs *), GFP_KERNEL);
	if (!dr)
		return ERR_PTR(-ENOMEM);

	descs = gpiod_get_array(dev, con_id, flags);
	if (IS_ERR(descs)) {
		devres_free(dr);
		return descs;
	}

	*dr = descs;
	devres_add(dev, dr);

	return descs;
}
EXPORT_SYMBOL(devm_gpiod_get_array);

/**
 * devm_gpiod_get_array_optional - Resource-managed gpiod_get_array_optional()
 * @dev:	GPIO consumer
 * @con_id:	function within the GPIO consumer
 * @flags:	optional GPIO initialization flags
 *
 * Managed gpiod_get_array_optional(). GPIO descriptors returned from this
 * function are automatically disposed on driver detach.
 * See gpiod_get_array_optional() for detailed information about behavior and
 * return values.
 */
struct gpio_descs *__must_check
devm_gpiod_get_array_optional(struct device *dev, const char *con_id,
			      enum gpiod_flags flags)
{
	struct gpio_descs *descs;

	descs = devm_gpiod_get_array(dev, con_id, flags);
	if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT))
		return NULL;

	return descs;
}
EXPORT_SYMBOL(devm_gpiod_get_array_optional);

/**
 * devm_gpiod_put - Resource-managed gpiod_put()
 * @desc:	GPIO descriptor to dispose of
 *
 * Dispose of a GPIO descriptor obtained with devm_gpiod_get() or
 * devm_gpiod_get_index(). Normally this function will not be called as the GPIO
 * will be disposed of by the resource management code.
 */
void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
{
	WARN_ON(devres_release(dev, devm_gpiod_release, devm_gpiod_match,
		&desc));
}
EXPORT_SYMBOL(devm_gpiod_put);

/**
 * devm_gpiod_put_array - Resource-managed gpiod_put_array()
 * @descs:	GPIO descriptor array to dispose of
 *
 * Dispose of an array of GPIO descriptors obtained with devm_gpiod_get_array().
 * Normally this function will not be called as the GPIOs will be disposed of
 * by the resource management code.
 */
void devm_gpiod_put_array(struct device *dev, struct gpio_descs *descs)
{
	WARN_ON(devres_release(dev, devm_gpiod_release_array,
			       devm_gpiod_match_array, &descs));
}
EXPORT_SYMBOL(devm_gpiod_put_array);




static void devm_gpio_release(struct device *dev, void *res)
{
	unsigned *gpio = res;

	gpio_free(*gpio);
}

static int devm_gpio_match(struct device *dev, void *res, void *data)
{
	unsigned *this = res, *gpio = data;

	return *this == *gpio;
}

/**
 *      devm_gpio_request - request a GPIO for a managed device
 *      @dev: device to request the GPIO for
 *      @gpio: GPIO to allocate
 *      @label: the name of the requested GPIO
 *
 *      Except for the extra @dev argument, this function takes the
 *      same arguments and performs the same function as
 *      gpio_request().  GPIOs requested with this function will be
 *      automatically freed on driver detach.
 *
 *      If an GPIO allocated with this function needs to be freed
 *      separately, devm_gpio_free() must be used.
 */

int devm_gpio_request(struct device *dev, unsigned gpio, const char *label)
{
	unsigned *dr;
	int rc;

	dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
	if (!dr)
		return -ENOMEM;

	rc = gpio_request(gpio, label);
	if (rc) {
		devres_free(dr);
		return rc;
	}

	*dr = gpio;
	devres_add(dev, dr);

	return 0;
}
EXPORT_SYMBOL(devm_gpio_request);

/**
 *	devm_gpio_request_one - request a single GPIO with initial setup
 *	@dev:   device to request for
 *	@gpio:	the GPIO number
 *	@flags:	GPIO configuration as specified by GPIOF_*
 *	@label:	a literal description string of this GPIO
 */
int devm_gpio_request_one(struct device *dev, unsigned gpio,
			  unsigned long flags, const char *label)
{
	unsigned *dr;
	int rc;

	dr = devres_alloc(devm_gpio_release, sizeof(unsigned), GFP_KERNEL);
	if (!dr)
		return -ENOMEM;

	rc = gpio_request_one(gpio, flags, label);
	if (rc) {
		devres_free(dr);
		return rc;
	}

	*dr = gpio;
	devres_add(dev, dr);

	return 0;
}
EXPORT_SYMBOL(devm_gpio_request_one);

/**
 *      devm_gpio_free - free a GPIO
 *      @dev: device to free GPIO for
 *      @gpio: GPIO to free
 *
 *      Except for the extra @dev argument, this function takes the
 *      same arguments and performs the same function as gpio_free().
 *      This function instead of gpio_free() should be used to manually
 *      free GPIOs allocated with devm_gpio_request().
 */
void devm_gpio_free(struct device *dev, unsigned int gpio)
{

	WARN_ON(devres_release(dev, devm_gpio_release, devm_gpio_match,
		&gpio));
}
EXPORT_SYMBOL(devm_gpio_free);