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CommitLineData
863fbf49
AV
1/*
2 * OF helpers for the GPIO API
3 *
4 * Copyright (c) 2007-2008 MontaVista Software, Inc.
5 *
6 * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 */
13
2e13cba8 14#include <linux/device.h>
bea4dbee 15#include <linux/err.h>
863fbf49 16#include <linux/errno.h>
2e13cba8 17#include <linux/module.h>
863fbf49 18#include <linux/io.h>
af8b6375 19#include <linux/gpio/consumer.h>
863fbf49 20#include <linux/of.h>
2e13cba8 21#include <linux/of_address.h>
863fbf49 22#include <linux/of_gpio.h>
f23f1516 23#include <linux/pinctrl/pinctrl.h>
2e13cba8 24#include <linux/slab.h>
f625d460 25#include <linux/gpio/machine.h>
863fbf49 26
1bd6b601 27#include "gpiolib.h"
af8b6375 28
c7e9d398 29static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip, void *data)
3d0f7cf0 30{
c7e9d398
MY
31 struct of_phandle_args *gpiospec = data;
32
33 return chip->gpiodev->dev.of_node == gpiospec->np &&
34 chip->of_xlate(chip, gpiospec, NULL) >= 0;
762c2e46 35}
3d0f7cf0 36
c7e9d398
MY
37static struct gpio_chip *of_find_gpiochip_by_xlate(
38 struct of_phandle_args *gpiospec)
762c2e46 39{
c7e9d398 40 return gpiochip_find(gpiospec, of_gpiochip_match_node_and_xlate);
3d0f7cf0 41}
3d0f7cf0 42
99468c1a
MY
43static struct gpio_desc *of_xlate_and_get_gpiod_flags(struct gpio_chip *chip,
44 struct of_phandle_args *gpiospec,
45 enum of_gpio_flags *flags)
3d0f7cf0 46{
3d0f7cf0
GL
47 int ret;
48
99468c1a
MY
49 if (chip->of_gpio_n_cells != gpiospec->args_count)
50 return ERR_PTR(-EINVAL);
51
52 ret = chip->of_xlate(chip, gpiospec, flags);
53 if (ret < 0)
54 return ERR_PTR(ret);
55
56 return gpiochip_get_desc(chip, ret);
3d0f7cf0
GL
57}
58
863fbf49 59/**
af8b6375 60 * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API
863fbf49 61 * @np: device node to get GPIO from
a6b09191 62 * @propname: property name containing gpio specifier(s)
863fbf49 63 * @index: index of the GPIO
b908b53d 64 * @flags: a flags pointer to fill in
863fbf49 65 *
af8b6375 66 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
b908b53d
AV
67 * value on the error condition. If @flags is not NULL the function also fills
68 * in flags for the GPIO.
863fbf49 69 */
af8b6375
AC
70struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
71 const char *propname, int index, enum of_gpio_flags *flags)
863fbf49 72{
762c2e46
MY
73 struct of_phandle_args gpiospec;
74 struct gpio_chip *chip;
75 struct gpio_desc *desc;
64b60e09 76 int ret;
3d0f7cf0 77
15c9a0ac 78 ret = of_parse_phandle_with_args(np, propname, "#gpio-cells", index,
762c2e46 79 &gpiospec);
64b60e09 80 if (ret) {
85ea29ac
TB
81 pr_debug("%s: can't parse '%s' property of node '%s[%d]'\n",
82 __func__, propname, np->full_name, index);
af8b6375 83 return ERR_PTR(ret);
863fbf49
AV
84 }
85
c7e9d398 86 chip = of_find_gpiochip_by_xlate(&gpiospec);
762c2e46
MY
87 if (!chip) {
88 desc = ERR_PTR(-EPROBE_DEFER);
89 goto out;
90 }
762c2e46 91
99468c1a 92 desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, flags);
762c2e46
MY
93 if (IS_ERR(desc))
94 goto out;
863fbf49 95
85ea29ac
TB
96 pr_debug("%s: parsed '%s' property of node '%s[%d]' - status (%d)\n",
97 __func__, propname, np->full_name, index,
762c2e46
MY
98 PTR_ERR_OR_ZERO(desc));
99
100out:
101 of_node_put(gpiospec.np);
102
103 return desc;
863fbf49 104}
863fbf49 105
f01d9075
AC
106int of_get_named_gpio_flags(struct device_node *np, const char *list_name,
107 int index, enum of_gpio_flags *flags)
108{
109 struct gpio_desc *desc;
110
111 desc = of_get_named_gpiod_flags(np, list_name, index, flags);
112
113 if (IS_ERR(desc))
114 return PTR_ERR(desc);
115 else
116 return desc_to_gpio(desc);
117}
118EXPORT_SYMBOL(of_get_named_gpio_flags);
119
ea713bc4
LW
120struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
121 unsigned int idx,
122 enum gpio_lookup_flags *flags)
123{
124 char prop_name[32]; /* 32 is max size of property name */
125 enum of_gpio_flags of_flags;
126 struct gpio_desc *desc;
127 unsigned int i;
128
129 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
130 if (con_id)
131 snprintf(prop_name, sizeof(prop_name), "%s-%s", con_id,
132 gpio_suffixes[i]);
133 else
134 snprintf(prop_name, sizeof(prop_name), "%s",
135 gpio_suffixes[i]);
136
137 desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx,
138 &of_flags);
139 if (!IS_ERR(desc) || (PTR_ERR(desc) != -ENOENT))
140 break;
141 }
142
143 if (IS_ERR(desc))
144 return desc;
145
146 if (of_flags & OF_GPIO_ACTIVE_LOW)
147 *flags |= GPIO_ACTIVE_LOW;
148
149 if (of_flags & OF_GPIO_SINGLE_ENDED) {
4c0facdd 150 if (of_flags & OF_GPIO_OPEN_DRAIN)
ea713bc4
LW
151 *flags |= GPIO_OPEN_DRAIN;
152 else
153 *flags |= GPIO_OPEN_SOURCE;
154 }
155
05f479bf
CK
156 if (of_flags & OF_GPIO_SLEEP_MAY_LOOSE_VALUE)
157 *flags |= GPIO_SLEEP_MAY_LOOSE_VALUE;
158
ea713bc4
LW
159 return desc;
160}
161
f625d460 162/**
fd7337fd 163 * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API
f625d460 164 * @np: device node to get GPIO from
be715343 165 * @chip: GPIO chip whose hog is parsed
a79fead5 166 * @idx: Index of the GPIO to parse
f625d460
BP
167 * @name: GPIO line name
168 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
fd7337fd 169 * of_parse_own_gpio()
f625d460
BP
170 * @dflags: gpiod_flags - optional GPIO initialization flags
171 *
172 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
173 * value on the error condition.
174 */
fd7337fd 175static struct gpio_desc *of_parse_own_gpio(struct device_node *np,
be715343 176 struct gpio_chip *chip,
a79fead5 177 unsigned int idx, const char **name,
fd7337fd
MP
178 enum gpio_lookup_flags *lflags,
179 enum gpiod_flags *dflags)
f625d460
BP
180{
181 struct device_node *chip_np;
182 enum of_gpio_flags xlate_flags;
be715343
MY
183 struct of_phandle_args gpiospec;
184 struct gpio_desc *desc;
a79fead5 185 unsigned int i;
f625d460 186 u32 tmp;
3f9547e1 187 int ret;
f625d460 188
be715343 189 chip_np = chip->of_node;
f625d460
BP
190 if (!chip_np)
191 return ERR_PTR(-EINVAL);
192
193 xlate_flags = 0;
194 *lflags = 0;
195 *dflags = 0;
196
197 ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp);
198 if (ret)
199 return ERR_PTR(ret);
200
be715343
MY
201 gpiospec.np = chip_np;
202 gpiospec.args_count = tmp;
f625d460 203
a79fead5
GU
204 for (i = 0; i < tmp; i++) {
205 ret = of_property_read_u32_index(np, "gpios", idx * tmp + i,
206 &gpiospec.args[i]);
207 if (ret)
208 return ERR_PTR(ret);
209 }
f625d460 210
99468c1a 211 desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, &xlate_flags);
be715343
MY
212 if (IS_ERR(desc))
213 return desc;
f625d460
BP
214
215 if (xlate_flags & OF_GPIO_ACTIVE_LOW)
216 *lflags |= GPIO_ACTIVE_LOW;
217
218 if (of_property_read_bool(np, "input"))
219 *dflags |= GPIOD_IN;
220 else if (of_property_read_bool(np, "output-low"))
221 *dflags |= GPIOD_OUT_LOW;
222 else if (of_property_read_bool(np, "output-high"))
223 *dflags |= GPIOD_OUT_HIGH;
224 else {
225 pr_warn("GPIO line %d (%s): no hogging state specified, bailing out\n",
be715343 226 desc_to_gpio(desc), np->name);
f625d460
BP
227 return ERR_PTR(-EINVAL);
228 }
229
230 if (name && of_property_read_string(np, "line-name", name))
231 *name = np->name;
232
be715343 233 return desc;
f625d460
BP
234}
235
236/**
fd7337fd 237 * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions
f625d460
BP
238 * @chip: gpio chip to act on
239 *
240 * This is only used by of_gpiochip_add to request/set GPIO initial
241 * configuration.
ead066e6 242 * It returns error if it fails otherwise 0 on success.
f625d460 243 */
dfbd379b 244static int of_gpiochip_scan_gpios(struct gpio_chip *chip)
f625d460
BP
245{
246 struct gpio_desc *desc = NULL;
247 struct device_node *np;
248 const char *name;
249 enum gpio_lookup_flags lflags;
250 enum gpiod_flags dflags;
a79fead5 251 unsigned int i;
dfbd379b 252 int ret;
f625d460 253
d1279d94 254 for_each_available_child_of_node(chip->of_node, np) {
f625d460
BP
255 if (!of_property_read_bool(np, "gpio-hog"))
256 continue;
257
a79fead5
GU
258 for (i = 0;; i++) {
259 desc = of_parse_own_gpio(np, chip, i, &name, &lflags,
260 &dflags);
261 if (IS_ERR(desc))
262 break;
263
264 ret = gpiod_hog(desc, name, lflags, dflags);
265 if (ret < 0) {
266 of_node_put(np);
267 return ret;
268 }
09e258af 269 }
f625d460 270 }
dfbd379b
LD
271
272 return 0;
f625d460
BP
273}
274
863fbf49 275/**
b908b53d 276 * of_gpio_simple_xlate - translate gpio_spec to the GPIO number and flags
a19e3da5 277 * @gc: pointer to the gpio_chip structure
863fbf49
AV
278 * @np: device node of the GPIO chip
279 * @gpio_spec: gpio specifier as found in the device tree
b908b53d 280 * @flags: a flags pointer to fill in
863fbf49
AV
281 *
282 * This is simple translation function, suitable for the most 1:1 mapped
283 * gpio chips. This function performs only one sanity check: whether gpio
284 * is less than ngpios (that is specified in the gpio_chip).
285 */
15c9a0ac
GL
286int of_gpio_simple_xlate(struct gpio_chip *gc,
287 const struct of_phandle_args *gpiospec, u32 *flags)
863fbf49 288{
b908b53d
AV
289 /*
290 * We're discouraging gpio_cells < 2, since that way you'll have to
20a8a968 291 * write your own xlate function (that will have to retrieve the GPIO
b908b53d
AV
292 * number and the flags from a single gpio cell -- this is possible,
293 * but not recommended).
294 */
a19e3da5 295 if (gc->of_gpio_n_cells < 2) {
b908b53d
AV
296 WARN_ON(1);
297 return -EINVAL;
298 }
299
15c9a0ac
GL
300 if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
301 return -EINVAL;
302
6270d830 303 if (gpiospec->args[0] >= gc->ngpio)
863fbf49
AV
304 return -EINVAL;
305
b908b53d 306 if (flags)
15c9a0ac 307 *flags = gpiospec->args[1];
b908b53d 308
15c9a0ac 309 return gpiospec->args[0];
863fbf49 310}
3038bbdf 311EXPORT_SYMBOL(of_gpio_simple_xlate);
863fbf49 312
863fbf49 313/**
3208b0f0 314 * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank)
863fbf49
AV
315 * @np: device node of the GPIO chip
316 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure
3208b0f0 317 * @data: driver data to store in the struct gpio_chip
863fbf49
AV
318 *
319 * To use this function you should allocate and fill mm_gc with:
320 *
321 * 1) In the gpio_chip structure:
322 * - all the callbacks
a19e3da5
AV
323 * - of_gpio_n_cells
324 * - of_xlate callback (optional)
863fbf49
AV
325 *
326 * 3) In the of_mm_gpio_chip structure:
327 * - save_regs callback (optional)
328 *
329 * If succeeded, this function will map bank's memory and will
330 * do all necessary work for you. Then you'll able to use .regs
331 * to manage GPIOs from the callbacks.
332 */
3208b0f0
LW
333int of_mm_gpiochip_add_data(struct device_node *np,
334 struct of_mm_gpio_chip *mm_gc,
335 void *data)
863fbf49
AV
336{
337 int ret = -ENOMEM;
a19e3da5 338 struct gpio_chip *gc = &mm_gc->gc;
863fbf49
AV
339
340 gc->label = kstrdup(np->full_name, GFP_KERNEL);
341 if (!gc->label)
342 goto err0;
343
344 mm_gc->regs = of_iomap(np, 0);
345 if (!mm_gc->regs)
346 goto err1;
347
21451155 348 gc->base = -1;
863fbf49 349
863fbf49
AV
350 if (mm_gc->save_regs)
351 mm_gc->save_regs(mm_gc);
352
a19e3da5 353 mm_gc->gc.of_node = np;
863fbf49 354
3208b0f0 355 ret = gpiochip_add_data(gc, data);
863fbf49
AV
356 if (ret)
357 goto err2;
358
863fbf49
AV
359 return 0;
360err2:
863fbf49
AV
361 iounmap(mm_gc->regs);
362err1:
363 kfree(gc->label);
364err0:
365 pr_err("%s: GPIO chip registration failed with status %d\n",
366 np->full_name, ret);
367 return ret;
368}
3208b0f0 369EXPORT_SYMBOL(of_mm_gpiochip_add_data);
594fa265 370
d621e8ba
RRD
371/**
372 * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank)
373 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure
374 */
375void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc)
376{
377 struct gpio_chip *gc = &mm_gc->gc;
378
379 if (!mm_gc)
380 return;
381
382 gpiochip_remove(gc);
383 iounmap(mm_gc->regs);
384 kfree(gc->label);
385}
386EXPORT_SYMBOL(of_mm_gpiochip_remove);
387
f23f1516 388#ifdef CONFIG_PINCTRL
28355f81 389static int of_gpiochip_add_pin_range(struct gpio_chip *chip)
f23f1516
SH
390{
391 struct device_node *np = chip->of_node;
f23f1516 392 struct of_phandle_args pinspec;
1e63d7b9 393 struct pinctrl_dev *pctldev;
f23f1516 394 int index = 0, ret;
586a87e6
CR
395 const char *name;
396 static const char group_names_propname[] = "gpio-ranges-group-names";
397 struct property *group_names;
f23f1516
SH
398
399 if (!np)
28355f81 400 return 0;
f23f1516 401
586a87e6
CR
402 group_names = of_find_property(np, group_names_propname, NULL);
403
ad4e1a7c 404 for (;; index++) {
d9fe0039
SW
405 ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3,
406 index, &pinspec);
f23f1516
SH
407 if (ret)
408 break;
409
1e63d7b9 410 pctldev = of_pinctrl_get(pinspec.np);
602cf638 411 of_node_put(pinspec.np);
1e63d7b9 412 if (!pctldev)
28355f81 413 return -EPROBE_DEFER;
f23f1516 414
586a87e6
CR
415 if (pinspec.args[2]) {
416 if (group_names) {
72858602 417 of_property_read_string_index(np,
586a87e6
CR
418 group_names_propname,
419 index, &name);
420 if (strlen(name)) {
421 pr_err("%s: Group name of numeric GPIO ranges must be the empty string.\n",
422 np->full_name);
423 break;
424 }
425 }
426 /* npins != 0: linear range */
427 ret = gpiochip_add_pin_range(chip,
428 pinctrl_dev_get_devname(pctldev),
429 pinspec.args[0],
430 pinspec.args[1],
431 pinspec.args[2]);
432 if (ret)
28355f81 433 return ret;
586a87e6
CR
434 } else {
435 /* npins == 0: special range */
436 if (pinspec.args[1]) {
437 pr_err("%s: Illegal gpio-range format.\n",
438 np->full_name);
439 break;
440 }
441
442 if (!group_names) {
443 pr_err("%s: GPIO group range requested but no %s property.\n",
444 np->full_name, group_names_propname);
445 break;
446 }
447
448 ret = of_property_read_string_index(np,
449 group_names_propname,
450 index, &name);
451 if (ret)
452 break;
453
454 if (!strlen(name)) {
455 pr_err("%s: Group name of GPIO group range cannot be the empty string.\n",
456 np->full_name);
457 break;
458 }
459
460 ret = gpiochip_add_pingroup_range(chip, pctldev,
461 pinspec.args[0], name);
462 if (ret)
28355f81 463 return ret;
586a87e6 464 }
ad4e1a7c 465 }
28355f81
TV
466
467 return 0;
f23f1516
SH
468}
469
f23f1516 470#else
28355f81 471static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; }
f23f1516
SH
472#endif
473
28355f81 474int of_gpiochip_add(struct gpio_chip *chip)
391c970c 475{
28355f81
TV
476 int status;
477
58383c78
LW
478 if ((!chip->of_node) && (chip->parent))
479 chip->of_node = chip->parent->of_node;
391c970c
AV
480
481 if (!chip->of_node)
28355f81 482 return 0;
391c970c
AV
483
484 if (!chip->of_xlate) {
485 chip->of_gpio_n_cells = 2;
486 chip->of_xlate = of_gpio_simple_xlate;
487 }
488
1020dfd1
MY
489 if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS)
490 return -EINVAL;
491
28355f81
TV
492 status = of_gpiochip_add_pin_range(chip);
493 if (status)
494 return status;
495
fd9c5531
LW
496 /* If the chip defines names itself, these take precedence */
497 if (!chip->names)
9427ecbe 498 devprop_gpiochip_set_names(chip);
fd9c5531 499
391c970c 500 of_node_get(chip->of_node);
f625d460 501
dfbd379b 502 return of_gpiochip_scan_gpios(chip);
391c970c
AV
503}
504
505void of_gpiochip_remove(struct gpio_chip *chip)
506{
e93fa3f2 507 gpiochip_remove_pin_ranges(chip);
8a691550 508 of_node_put(chip->of_node);
391c970c 509}