Merge tag 'pm+acpi-4.6-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael...
[linux-2.6-block.git] / drivers / gpio / gpiolib-of.c
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
0df2c999 29/* Private data structure for of_gpiochip_find_and_xlate */
3d0f7cf0
GL
30struct gg_data {
31 enum of_gpio_flags *flags;
32 struct of_phandle_args gpiospec;
33
af8b6375 34 struct gpio_desc *out_gpio;
3d0f7cf0
GL
35};
36
37/* Private function for resolving node pointer to gpio_chip */
38static int of_gpiochip_find_and_xlate(struct gpio_chip *gc, void *data)
39{
40 struct gg_data *gg_data = data;
41 int ret;
42
43 if ((gc->of_node != gg_data->gpiospec.np) ||
44 (gc->of_gpio_n_cells != gg_data->gpiospec.args_count) ||
45 (!gc->of_xlate))
46 return false;
47
48 ret = gc->of_xlate(gc, &gg_data->gpiospec, gg_data->flags);
7b8792bb 49 if (ret < 0) {
9cf75e9e
HH
50 /* We've found a gpio chip, but the translation failed.
51 * Store translation error in out_gpio.
52 * Return false to keep looking, as more than one gpio chip
53 * could be registered per of-node.
7b8792bb
HH
54 */
55 gg_data->out_gpio = ERR_PTR(ret);
9cf75e9e 56 return false;
7b8792bb 57 }
3d0f7cf0 58
ccd9726e 59 gg_data->out_gpio = gpiochip_get_desc(gc, ret);
3d0f7cf0
GL
60 return true;
61}
62
863fbf49 63/**
af8b6375 64 * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API
863fbf49 65 * @np: device node to get GPIO from
a6b09191 66 * @propname: property name containing gpio specifier(s)
863fbf49 67 * @index: index of the GPIO
b908b53d 68 * @flags: a flags pointer to fill in
863fbf49 69 *
af8b6375 70 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
b908b53d
AV
71 * value on the error condition. If @flags is not NULL the function also fills
72 * in flags for the GPIO.
863fbf49 73 */
af8b6375
AC
74struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
75 const char *propname, int index, enum of_gpio_flags *flags)
863fbf49 76{
4fbb0022
RS
77 /* Return -EPROBE_DEFER to support probe() functions to be called
78 * later when the GPIO actually becomes available
79 */
af8b6375
AC
80 struct gg_data gg_data = {
81 .flags = flags,
82 .out_gpio = ERR_PTR(-EPROBE_DEFER)
83 };
64b60e09 84 int ret;
3d0f7cf0
GL
85
86 /* .of_xlate might decide to not fill in the flags, so clear it. */
87 if (flags)
88 *flags = 0;
863fbf49 89
15c9a0ac 90 ret = of_parse_phandle_with_args(np, propname, "#gpio-cells", index,
3d0f7cf0 91 &gg_data.gpiospec);
64b60e09 92 if (ret) {
85ea29ac
TB
93 pr_debug("%s: can't parse '%s' property of node '%s[%d]'\n",
94 __func__, propname, np->full_name, index);
af8b6375 95 return ERR_PTR(ret);
863fbf49
AV
96 }
97
3d0f7cf0 98 gpiochip_find(&gg_data, of_gpiochip_find_and_xlate);
863fbf49 99
3d0f7cf0 100 of_node_put(gg_data.gpiospec.np);
85ea29ac
TB
101 pr_debug("%s: parsed '%s' property of node '%s[%d]' - status (%d)\n",
102 __func__, propname, np->full_name, index,
bea4dbee 103 PTR_ERR_OR_ZERO(gg_data.out_gpio));
3d0f7cf0 104 return gg_data.out_gpio;
863fbf49 105}
863fbf49 106
f01d9075
AC
107int of_get_named_gpio_flags(struct device_node *np, const char *list_name,
108 int index, enum of_gpio_flags *flags)
109{
110 struct gpio_desc *desc;
111
112 desc = of_get_named_gpiod_flags(np, list_name, index, flags);
113
114 if (IS_ERR(desc))
115 return PTR_ERR(desc);
116 else
117 return desc_to_gpio(desc);
118}
119EXPORT_SYMBOL(of_get_named_gpio_flags);
120
f625d460 121/**
fd7337fd 122 * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API
f625d460
BP
123 * @np: device node to get GPIO from
124 * @name: GPIO line name
125 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
fd7337fd 126 * of_parse_own_gpio()
f625d460
BP
127 * @dflags: gpiod_flags - optional GPIO initialization flags
128 *
129 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
130 * value on the error condition.
131 */
fd7337fd
MP
132static struct gpio_desc *of_parse_own_gpio(struct device_node *np,
133 const char **name,
134 enum gpio_lookup_flags *lflags,
135 enum gpiod_flags *dflags)
f625d460
BP
136{
137 struct device_node *chip_np;
138 enum of_gpio_flags xlate_flags;
f625d460
BP
139 struct gg_data gg_data = {
140 .flags = &xlate_flags,
141 };
142 u32 tmp;
143 int i, ret;
144
145 chip_np = np->parent;
146 if (!chip_np)
147 return ERR_PTR(-EINVAL);
148
149 xlate_flags = 0;
150 *lflags = 0;
151 *dflags = 0;
152
153 ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp);
154 if (ret)
155 return ERR_PTR(ret);
156
157 if (tmp > MAX_PHANDLE_ARGS)
158 return ERR_PTR(-EINVAL);
159
160 gg_data.gpiospec.args_count = tmp;
161 gg_data.gpiospec.np = chip_np;
162 for (i = 0; i < tmp; i++) {
163 ret = of_property_read_u32_index(np, "gpios", i,
164 &gg_data.gpiospec.args[i]);
165 if (ret)
166 return ERR_PTR(ret);
167 }
168
169 gpiochip_find(&gg_data, of_gpiochip_find_and_xlate);
170 if (!gg_data.out_gpio) {
171 if (np->parent == np)
172 return ERR_PTR(-ENXIO);
173 else
174 return ERR_PTR(-EINVAL);
175 }
176
177 if (xlate_flags & OF_GPIO_ACTIVE_LOW)
178 *lflags |= GPIO_ACTIVE_LOW;
179
180 if (of_property_read_bool(np, "input"))
181 *dflags |= GPIOD_IN;
182 else if (of_property_read_bool(np, "output-low"))
183 *dflags |= GPIOD_OUT_LOW;
184 else if (of_property_read_bool(np, "output-high"))
185 *dflags |= GPIOD_OUT_HIGH;
186 else {
187 pr_warn("GPIO line %d (%s): no hogging state specified, bailing out\n",
188 desc_to_gpio(gg_data.out_gpio), np->name);
189 return ERR_PTR(-EINVAL);
190 }
191
192 if (name && of_property_read_string(np, "line-name", name))
193 *name = np->name;
194
39561e8b 195 return gg_data.out_gpio;
f625d460
BP
196}
197
198/**
fd7337fd 199 * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions
f625d460
BP
200 * @chip: gpio chip to act on
201 *
202 * This is only used by of_gpiochip_add to request/set GPIO initial
203 * configuration.
204 */
fd7337fd 205static void of_gpiochip_scan_gpios(struct gpio_chip *chip)
f625d460
BP
206{
207 struct gpio_desc *desc = NULL;
208 struct device_node *np;
209 const char *name;
210 enum gpio_lookup_flags lflags;
211 enum gpiod_flags dflags;
212
213 for_each_child_of_node(chip->of_node, np) {
214 if (!of_property_read_bool(np, "gpio-hog"))
215 continue;
216
fd7337fd 217 desc = of_parse_own_gpio(np, &name, &lflags, &dflags);
f625d460
BP
218 if (IS_ERR(desc))
219 continue;
220
221 if (gpiod_hog(desc, name, lflags, dflags))
222 continue;
223 }
224}
225
863fbf49 226/**
b908b53d 227 * of_gpio_simple_xlate - translate gpio_spec to the GPIO number and flags
a19e3da5 228 * @gc: pointer to the gpio_chip structure
863fbf49
AV
229 * @np: device node of the GPIO chip
230 * @gpio_spec: gpio specifier as found in the device tree
b908b53d 231 * @flags: a flags pointer to fill in
863fbf49
AV
232 *
233 * This is simple translation function, suitable for the most 1:1 mapped
234 * gpio chips. This function performs only one sanity check: whether gpio
235 * is less than ngpios (that is specified in the gpio_chip).
236 */
15c9a0ac
GL
237int of_gpio_simple_xlate(struct gpio_chip *gc,
238 const struct of_phandle_args *gpiospec, u32 *flags)
863fbf49 239{
b908b53d
AV
240 /*
241 * We're discouraging gpio_cells < 2, since that way you'll have to
20a8a968 242 * write your own xlate function (that will have to retrieve the GPIO
b908b53d
AV
243 * number and the flags from a single gpio cell -- this is possible,
244 * but not recommended).
245 */
a19e3da5 246 if (gc->of_gpio_n_cells < 2) {
b908b53d
AV
247 WARN_ON(1);
248 return -EINVAL;
249 }
250
15c9a0ac
GL
251 if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
252 return -EINVAL;
253
6270d830 254 if (gpiospec->args[0] >= gc->ngpio)
863fbf49
AV
255 return -EINVAL;
256
b908b53d 257 if (flags)
15c9a0ac 258 *flags = gpiospec->args[1];
b908b53d 259
15c9a0ac 260 return gpiospec->args[0];
863fbf49 261}
3038bbdf 262EXPORT_SYMBOL(of_gpio_simple_xlate);
863fbf49 263
863fbf49 264/**
3208b0f0 265 * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank)
863fbf49
AV
266 * @np: device node of the GPIO chip
267 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure
3208b0f0 268 * @data: driver data to store in the struct gpio_chip
863fbf49
AV
269 *
270 * To use this function you should allocate and fill mm_gc with:
271 *
272 * 1) In the gpio_chip structure:
273 * - all the callbacks
a19e3da5
AV
274 * - of_gpio_n_cells
275 * - of_xlate callback (optional)
863fbf49
AV
276 *
277 * 3) In the of_mm_gpio_chip structure:
278 * - save_regs callback (optional)
279 *
280 * If succeeded, this function will map bank's memory and will
281 * do all necessary work for you. Then you'll able to use .regs
282 * to manage GPIOs from the callbacks.
283 */
3208b0f0
LW
284int of_mm_gpiochip_add_data(struct device_node *np,
285 struct of_mm_gpio_chip *mm_gc,
286 void *data)
863fbf49
AV
287{
288 int ret = -ENOMEM;
a19e3da5 289 struct gpio_chip *gc = &mm_gc->gc;
863fbf49
AV
290
291 gc->label = kstrdup(np->full_name, GFP_KERNEL);
292 if (!gc->label)
293 goto err0;
294
295 mm_gc->regs = of_iomap(np, 0);
296 if (!mm_gc->regs)
297 goto err1;
298
21451155 299 gc->base = -1;
863fbf49 300
863fbf49
AV
301 if (mm_gc->save_regs)
302 mm_gc->save_regs(mm_gc);
303
a19e3da5 304 mm_gc->gc.of_node = np;
863fbf49 305
3208b0f0 306 ret = gpiochip_add_data(gc, data);
863fbf49
AV
307 if (ret)
308 goto err2;
309
863fbf49
AV
310 return 0;
311err2:
863fbf49
AV
312 iounmap(mm_gc->regs);
313err1:
314 kfree(gc->label);
315err0:
316 pr_err("%s: GPIO chip registration failed with status %d\n",
317 np->full_name, ret);
318 return ret;
319}
3208b0f0 320EXPORT_SYMBOL(of_mm_gpiochip_add_data);
594fa265 321
d621e8ba
RRD
322/**
323 * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank)
324 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure
325 */
326void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc)
327{
328 struct gpio_chip *gc = &mm_gc->gc;
329
330 if (!mm_gc)
331 return;
332
333 gpiochip_remove(gc);
334 iounmap(mm_gc->regs);
335 kfree(gc->label);
336}
337EXPORT_SYMBOL(of_mm_gpiochip_remove);
338
f23f1516 339#ifdef CONFIG_PINCTRL
28355f81 340static int of_gpiochip_add_pin_range(struct gpio_chip *chip)
f23f1516
SH
341{
342 struct device_node *np = chip->of_node;
f23f1516 343 struct of_phandle_args pinspec;
1e63d7b9 344 struct pinctrl_dev *pctldev;
f23f1516 345 int index = 0, ret;
586a87e6
CR
346 const char *name;
347 static const char group_names_propname[] = "gpio-ranges-group-names";
348 struct property *group_names;
f23f1516
SH
349
350 if (!np)
28355f81 351 return 0;
f23f1516 352
586a87e6
CR
353 group_names = of_find_property(np, group_names_propname, NULL);
354
ad4e1a7c 355 for (;; index++) {
d9fe0039
SW
356 ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3,
357 index, &pinspec);
f23f1516
SH
358 if (ret)
359 break;
360
1e63d7b9
LW
361 pctldev = of_pinctrl_get(pinspec.np);
362 if (!pctldev)
28355f81 363 return -EPROBE_DEFER;
f23f1516 364
586a87e6
CR
365 if (pinspec.args[2]) {
366 if (group_names) {
72858602 367 of_property_read_string_index(np,
586a87e6
CR
368 group_names_propname,
369 index, &name);
370 if (strlen(name)) {
371 pr_err("%s: Group name of numeric GPIO ranges must be the empty string.\n",
372 np->full_name);
373 break;
374 }
375 }
376 /* npins != 0: linear range */
377 ret = gpiochip_add_pin_range(chip,
378 pinctrl_dev_get_devname(pctldev),
379 pinspec.args[0],
380 pinspec.args[1],
381 pinspec.args[2]);
382 if (ret)
28355f81 383 return ret;
586a87e6
CR
384 } else {
385 /* npins == 0: special range */
386 if (pinspec.args[1]) {
387 pr_err("%s: Illegal gpio-range format.\n",
388 np->full_name);
389 break;
390 }
391
392 if (!group_names) {
393 pr_err("%s: GPIO group range requested but no %s property.\n",
394 np->full_name, group_names_propname);
395 break;
396 }
397
398 ret = of_property_read_string_index(np,
399 group_names_propname,
400 index, &name);
401 if (ret)
402 break;
403
404 if (!strlen(name)) {
405 pr_err("%s: Group name of GPIO group range cannot be the empty string.\n",
406 np->full_name);
407 break;
408 }
409
410 ret = gpiochip_add_pingroup_range(chip, pctldev,
411 pinspec.args[0], name);
412 if (ret)
28355f81 413 return ret;
586a87e6 414 }
ad4e1a7c 415 }
28355f81
TV
416
417 return 0;
f23f1516
SH
418}
419
f23f1516 420#else
28355f81 421static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; }
f23f1516
SH
422#endif
423
28355f81 424int of_gpiochip_add(struct gpio_chip *chip)
391c970c 425{
28355f81
TV
426 int status;
427
58383c78
LW
428 if ((!chip->of_node) && (chip->parent))
429 chip->of_node = chip->parent->of_node;
391c970c
AV
430
431 if (!chip->of_node)
28355f81 432 return 0;
391c970c
AV
433
434 if (!chip->of_xlate) {
435 chip->of_gpio_n_cells = 2;
436 chip->of_xlate = of_gpio_simple_xlate;
437 }
438
28355f81
TV
439 status = of_gpiochip_add_pin_range(chip);
440 if (status)
441 return status;
442
391c970c 443 of_node_get(chip->of_node);
f625d460 444
fd7337fd 445 of_gpiochip_scan_gpios(chip);
28355f81
TV
446
447 return 0;
391c970c
AV
448}
449
450void of_gpiochip_remove(struct gpio_chip *chip)
451{
e93fa3f2 452 gpiochip_remove_pin_ranges(chip);
8a691550 453 of_node_put(chip->of_node);
391c970c 454}