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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
14#include <linux/device.h>
15#include <linux/err.h>
16#include <linux/errno.h>
17#include <linux/module.h>
18#include <linux/io.h>
19#include <linux/gpio/consumer.h>
20#include <linux/of.h>
21#include <linux/of_address.h>
22#include <linux/of_gpio.h>
23#include <linux/pinctrl/pinctrl.h>
24#include <linux/slab.h>
25#include <linux/gpio/machine.h>
26
27#include "gpiolib.h"
28
29/* Private data structure for of_gpiochip_find_and_xlate */
30struct gg_data {
31 enum of_gpio_flags *flags;
32 struct of_phandle_args gpiospec;
33
34 struct gpio_desc *out_gpio;
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);
49 if (ret < 0) {
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.
54 */
55 gg_data->out_gpio = ERR_PTR(ret);
56 return false;
57 }
58
59 gg_data->out_gpio = gpiochip_get_desc(gc, ret);
60 return true;
61}
62
63/**
64 * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API
65 * @np: device node to get GPIO from
66 * @propname: property name containing gpio specifier(s)
67 * @index: index of the GPIO
68 * @flags: a flags pointer to fill in
69 *
70 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
71 * value on the error condition. If @flags is not NULL the function also fills
72 * in flags for the GPIO.
73 */
74struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
75 const char *propname, int index, enum of_gpio_flags *flags)
76{
77 /* Return -EPROBE_DEFER to support probe() functions to be called
78 * later when the GPIO actually becomes available
79 */
80 struct gg_data gg_data = {
81 .flags = flags,
82 .out_gpio = ERR_PTR(-EPROBE_DEFER)
83 };
84 int ret;
85
86 /* .of_xlate might decide to not fill in the flags, so clear it. */
87 if (flags)
88 *flags = 0;
89
90 ret = of_parse_phandle_with_args(np, propname, "#gpio-cells", index,
91 &gg_data.gpiospec);
92 if (ret) {
93 pr_debug("%s: can't parse '%s' property of node '%s[%d]'\n",
94 __func__, propname, np->full_name, index);
95 return ERR_PTR(ret);
96 }
97
98 gpiochip_find(&gg_data, of_gpiochip_find_and_xlate);
99
100 of_node_put(gg_data.gpiospec.np);
101 pr_debug("%s: parsed '%s' property of node '%s[%d]' - status (%d)\n",
102 __func__, propname, np->full_name, index,
103 PTR_ERR_OR_ZERO(gg_data.out_gpio));
104 return gg_data.out_gpio;
105}
106
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
121/**
122 * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API
123 * @np: device node to get GPIO from
124 * @name: GPIO line name
125 * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
126 * of_parse_own_gpio()
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 */
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)
136{
137 struct device_node *chip_np;
138 enum of_gpio_flags xlate_flags;
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
195 return gg_data.out_gpio;
196}
197
198/**
199 * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions
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 */
205static void of_gpiochip_scan_gpios(struct gpio_chip *chip)
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
217 desc = of_parse_own_gpio(np, &name, &lflags, &dflags);
218 if (IS_ERR(desc))
219 continue;
220
221 if (gpiod_hog(desc, name, lflags, dflags))
222 continue;
223 }
224}
225
226/**
227 * of_gpio_simple_xlate - translate gpio_spec to the GPIO number and flags
228 * @gc: pointer to the gpio_chip structure
229 * @np: device node of the GPIO chip
230 * @gpio_spec: gpio specifier as found in the device tree
231 * @flags: a flags pointer to fill in
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 */
237int of_gpio_simple_xlate(struct gpio_chip *gc,
238 const struct of_phandle_args *gpiospec, u32 *flags)
239{
240 /*
241 * We're discouraging gpio_cells < 2, since that way you'll have to
242 * write your own xlate function (that will have to retrieve the GPIO
243 * number and the flags from a single gpio cell -- this is possible,
244 * but not recommended).
245 */
246 if (gc->of_gpio_n_cells < 2) {
247 WARN_ON(1);
248 return -EINVAL;
249 }
250
251 if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
252 return -EINVAL;
253
254 if (gpiospec->args[0] >= gc->ngpio)
255 return -EINVAL;
256
257 if (flags)
258 *flags = gpiospec->args[1];
259
260 return gpiospec->args[0];
261}
262EXPORT_SYMBOL(of_gpio_simple_xlate);
263
264/**
265 * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank)
266 * @np: device node of the GPIO chip
267 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure
268 * @data: driver data to store in the struct gpio_chip
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
274 * - of_gpio_n_cells
275 * - of_xlate callback (optional)
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 */
284int of_mm_gpiochip_add_data(struct device_node *np,
285 struct of_mm_gpio_chip *mm_gc,
286 void *data)
287{
288 int ret = -ENOMEM;
289 struct gpio_chip *gc = &mm_gc->gc;
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
299 gc->base = -1;
300
301 if (mm_gc->save_regs)
302 mm_gc->save_regs(mm_gc);
303
304 mm_gc->gc.of_node = np;
305
306 ret = gpiochip_add_data(gc, data);
307 if (ret)
308 goto err2;
309
310 return 0;
311err2:
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}
320EXPORT_SYMBOL(of_mm_gpiochip_add_data);
321
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
339#ifdef CONFIG_PINCTRL
340static int of_gpiochip_add_pin_range(struct gpio_chip *chip)
341{
342 struct device_node *np = chip->of_node;
343 struct of_phandle_args pinspec;
344 struct pinctrl_dev *pctldev;
345 int index = 0, ret;
346 const char *name;
347 static const char group_names_propname[] = "gpio-ranges-group-names";
348 struct property *group_names;
349
350 if (!np)
351 return 0;
352
353 group_names = of_find_property(np, group_names_propname, NULL);
354
355 for (;; index++) {
356 ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3,
357 index, &pinspec);
358 if (ret)
359 break;
360
361 pctldev = of_pinctrl_get(pinspec.np);
362 if (!pctldev)
363 return -EPROBE_DEFER;
364
365 if (pinspec.args[2]) {
366 if (group_names) {
367 of_property_read_string_index(np,
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)
383 return ret;
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)
413 return ret;
414 }
415 }
416
417 return 0;
418}
419
420#else
421static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; }
422#endif
423
424int of_gpiochip_add(struct gpio_chip *chip)
425{
426 int status;
427
428 if ((!chip->of_node) && (chip->parent))
429 chip->of_node = chip->parent->of_node;
430
431 if (!chip->of_node)
432 return 0;
433
434 if (!chip->of_xlate) {
435 chip->of_gpio_n_cells = 2;
436 chip->of_xlate = of_gpio_simple_xlate;
437 }
438
439 status = of_gpiochip_add_pin_range(chip);
440 if (status)
441 return status;
442
443 of_node_get(chip->of_node);
444
445 of_gpiochip_scan_gpios(chip);
446
447 return 0;
448}
449
450void of_gpiochip_remove(struct gpio_chip *chip)
451{
452 gpiochip_remove_pin_ranges(chip);
453 of_node_put(chip->of_node);
454}
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * OF helpers for the GPIO API
4 *
5 * Copyright (c) 2007-2008 MontaVista Software, Inc.
6 *
7 * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
8 */
9
10#include <linux/device.h>
11#include <linux/err.h>
12#include <linux/errno.h>
13#include <linux/module.h>
14#include <linux/io.h>
15#include <linux/gpio/consumer.h>
16#include <linux/of.h>
17#include <linux/of_address.h>
18#include <linux/of_gpio.h>
19#include <linux/pinctrl/pinctrl.h>
20#include <linux/slab.h>
21#include <linux/gpio/machine.h>
22
23#include "gpiolib.h"
24#include "gpiolib-of.h"
25
26/*
27 * This is used by external users of of_gpio_count() from <linux/of_gpio.h>
28 *
29 * FIXME: get rid of those external users by converting them to GPIO
30 * descriptors and let them all use gpiod_get_count()
31 */
32int of_gpio_get_count(struct device *dev, const char *con_id)
33{
34 int ret;
35 char propname[32];
36 unsigned int i;
37
38 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
39 if (con_id)
40 snprintf(propname, sizeof(propname), "%s-%s",
41 con_id, gpio_suffixes[i]);
42 else
43 snprintf(propname, sizeof(propname), "%s",
44 gpio_suffixes[i]);
45
46 ret = of_gpio_named_count(dev->of_node, propname);
47 if (ret > 0)
48 break;
49 }
50 return ret ? ret : -ENOENT;
51}
52
53static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip, void *data)
54{
55 struct of_phandle_args *gpiospec = data;
56
57 return chip->gpiodev->dev.of_node == gpiospec->np &&
58 chip->of_xlate &&
59 chip->of_xlate(chip, gpiospec, NULL) >= 0;
60}
61
62static struct gpio_chip *of_find_gpiochip_by_xlate(
63 struct of_phandle_args *gpiospec)
64{
65 return gpiochip_find(gpiospec, of_gpiochip_match_node_and_xlate);
66}
67
68static struct gpio_desc *of_xlate_and_get_gpiod_flags(struct gpio_chip *chip,
69 struct of_phandle_args *gpiospec,
70 enum of_gpio_flags *flags)
71{
72 int ret;
73
74 if (chip->of_gpio_n_cells != gpiospec->args_count)
75 return ERR_PTR(-EINVAL);
76
77 ret = chip->of_xlate(chip, gpiospec, flags);
78 if (ret < 0)
79 return ERR_PTR(ret);
80
81 return gpiochip_get_desc(chip, ret);
82}
83
84/**
85 * of_gpio_need_valid_mask() - figure out if the OF GPIO driver needs
86 * to set the .valid_mask
87 * @dev: the device for the GPIO provider
88 * @return: true if the valid mask needs to be set
89 */
90bool of_gpio_need_valid_mask(const struct gpio_chip *gc)
91{
92 int size;
93 struct device_node *np = gc->of_node;
94
95 size = of_property_count_u32_elems(np, "gpio-reserved-ranges");
96 if (size > 0 && size % 2 == 0)
97 return true;
98 return false;
99}
100
101static void of_gpio_flags_quirks(struct device_node *np,
102 const char *propname,
103 enum of_gpio_flags *flags,
104 int index)
105{
106 /*
107 * Handle MMC "cd-inverted" and "wp-inverted" semantics.
108 */
109 if (IS_ENABLED(CONFIG_MMC)) {
110 /*
111 * Active low is the default according to the
112 * SDHCI specification and the device tree
113 * bindings. However the code in the current
114 * kernel was written such that the phandle
115 * flags were always respected, and "cd-inverted"
116 * would invert the flag from the device phandle.
117 */
118 if (!strcmp(propname, "cd-gpios")) {
119 if (of_property_read_bool(np, "cd-inverted"))
120 *flags ^= OF_GPIO_ACTIVE_LOW;
121 }
122 if (!strcmp(propname, "wp-gpios")) {
123 if (of_property_read_bool(np, "wp-inverted"))
124 *flags ^= OF_GPIO_ACTIVE_LOW;
125 }
126 }
127 /*
128 * Some GPIO fixed regulator quirks.
129 * Note that active low is the default.
130 */
131 if (IS_ENABLED(CONFIG_REGULATOR) &&
132 (of_device_is_compatible(np, "regulator-fixed") ||
133 of_device_is_compatible(np, "reg-fixed-voltage") ||
134 (!(strcmp(propname, "enable-gpio") &&
135 strcmp(propname, "enable-gpios")) &&
136 of_device_is_compatible(np, "regulator-gpio")))) {
137 /*
138 * The regulator GPIO handles are specified such that the
139 * presence or absence of "enable-active-high" solely controls
140 * the polarity of the GPIO line. Any phandle flags must
141 * be actively ignored.
142 */
143 if (*flags & OF_GPIO_ACTIVE_LOW) {
144 pr_warn("%s GPIO handle specifies active low - ignored\n",
145 of_node_full_name(np));
146 *flags &= ~OF_GPIO_ACTIVE_LOW;
147 }
148 if (!of_property_read_bool(np, "enable-active-high"))
149 *flags |= OF_GPIO_ACTIVE_LOW;
150 }
151 /*
152 * Legacy open drain handling for fixed voltage regulators.
153 */
154 if (IS_ENABLED(CONFIG_REGULATOR) &&
155 of_device_is_compatible(np, "reg-fixed-voltage") &&
156 of_property_read_bool(np, "gpio-open-drain")) {
157 *flags |= (OF_GPIO_SINGLE_ENDED | OF_GPIO_OPEN_DRAIN);
158 pr_info("%s uses legacy open drain flag - update the DTS if you can\n",
159 of_node_full_name(np));
160 }
161
162 /*
163 * Legacy handling of SPI active high chip select. If we have a
164 * property named "cs-gpios" we need to inspect the child node
165 * to determine if the flags should have inverted semantics.
166 */
167 if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") &&
168 of_property_read_bool(np, "cs-gpios")) {
169 struct device_node *child;
170 u32 cs;
171 int ret;
172
173 for_each_child_of_node(np, child) {
174 ret = of_property_read_u32(child, "reg", &cs);
175 if (ret)
176 continue;
177 if (cs == index) {
178 /*
179 * SPI children have active low chip selects
180 * by default. This can be specified negatively
181 * by just omitting "spi-cs-high" in the
182 * device node, or actively by tagging on
183 * GPIO_ACTIVE_LOW as flag in the device
184 * tree. If the line is simultaneously
185 * tagged as active low in the device tree
186 * and has the "spi-cs-high" set, we get a
187 * conflict and the "spi-cs-high" flag will
188 * take precedence.
189 */
190 if (of_property_read_bool(child, "spi-cs-high")) {
191 if (*flags & OF_GPIO_ACTIVE_LOW) {
192 pr_warn("%s GPIO handle specifies active low - ignored\n",
193 of_node_full_name(child));
194 *flags &= ~OF_GPIO_ACTIVE_LOW;
195 }
196 } else {
197 if (!(*flags & OF_GPIO_ACTIVE_LOW))
198 pr_info("%s enforce active low on chipselect handle\n",
199 of_node_full_name(child));
200 *flags |= OF_GPIO_ACTIVE_LOW;
201 }
202 of_node_put(child);
203 break;
204 }
205 }
206 }
207
208 /* Legacy handling of stmmac's active-low PHY reset line */
209 if (IS_ENABLED(CONFIG_STMMAC_ETH) &&
210 !strcmp(propname, "snps,reset-gpio") &&
211 of_property_read_bool(np, "snps,reset-active-low"))
212 *flags |= OF_GPIO_ACTIVE_LOW;
213}
214
215/**
216 * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API
217 * @np: device node to get GPIO from
218 * @propname: property name containing gpio specifier(s)
219 * @index: index of the GPIO
220 * @flags: a flags pointer to fill in
221 *
222 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
223 * value on the error condition. If @flags is not NULL the function also fills
224 * in flags for the GPIO.
225 */
226static struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
227 const char *propname, int index, enum of_gpio_flags *flags)
228{
229 struct of_phandle_args gpiospec;
230 struct gpio_chip *chip;
231 struct gpio_desc *desc;
232 int ret;
233
234 ret = of_parse_phandle_with_args_map(np, propname, "gpio", index,
235 &gpiospec);
236 if (ret) {
237 pr_debug("%s: can't parse '%s' property of node '%pOF[%d]'\n",
238 __func__, propname, np, index);
239 return ERR_PTR(ret);
240 }
241
242 chip = of_find_gpiochip_by_xlate(&gpiospec);
243 if (!chip) {
244 desc = ERR_PTR(-EPROBE_DEFER);
245 goto out;
246 }
247
248 desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, flags);
249 if (IS_ERR(desc))
250 goto out;
251
252 if (flags)
253 of_gpio_flags_quirks(np, propname, flags, index);
254
255 pr_debug("%s: parsed '%s' property of node '%pOF[%d]' - status (%d)\n",
256 __func__, propname, np, index,
257 PTR_ERR_OR_ZERO(desc));
258
259out:
260 of_node_put(gpiospec.np);
261
262 return desc;
263}
264
265int of_get_named_gpio_flags(struct device_node *np, const char *list_name,
266 int index, enum of_gpio_flags *flags)
267{
268 struct gpio_desc *desc;
269
270 desc = of_get_named_gpiod_flags(np, list_name, index, flags);
271
272 if (IS_ERR(desc))
273 return PTR_ERR(desc);
274 else
275 return desc_to_gpio(desc);
276}
277EXPORT_SYMBOL_GPL(of_get_named_gpio_flags);
278
279/**
280 * gpiod_get_from_of_node() - obtain a GPIO from an OF node
281 * @node: handle of the OF node
282 * @propname: name of the DT property representing the GPIO
283 * @index: index of the GPIO to obtain for the consumer
284 * @dflags: GPIO initialization flags
285 * @label: label to attach to the requested GPIO
286 *
287 * Returns:
288 * On successful request the GPIO pin is configured in accordance with
289 * provided @dflags.
290 *
291 * In case of error an ERR_PTR() is returned.
292 */
293struct gpio_desc *gpiod_get_from_of_node(struct device_node *node,
294 const char *propname, int index,
295 enum gpiod_flags dflags,
296 const char *label)
297{
298 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
299 struct gpio_desc *desc;
300 enum of_gpio_flags flags;
301 bool active_low = false;
302 bool single_ended = false;
303 bool open_drain = false;
304 bool transitory = false;
305 int ret;
306
307 desc = of_get_named_gpiod_flags(node, propname,
308 index, &flags);
309
310 if (!desc || IS_ERR(desc)) {
311 return desc;
312 }
313
314 active_low = flags & OF_GPIO_ACTIVE_LOW;
315 single_ended = flags & OF_GPIO_SINGLE_ENDED;
316 open_drain = flags & OF_GPIO_OPEN_DRAIN;
317 transitory = flags & OF_GPIO_TRANSITORY;
318
319 ret = gpiod_request(desc, label);
320 if (ret == -EBUSY && (dflags & GPIOD_FLAGS_BIT_NONEXCLUSIVE))
321 return desc;
322 if (ret)
323 return ERR_PTR(ret);
324
325 if (active_low)
326 lflags |= GPIO_ACTIVE_LOW;
327
328 if (single_ended) {
329 if (open_drain)
330 lflags |= GPIO_OPEN_DRAIN;
331 else
332 lflags |= GPIO_OPEN_SOURCE;
333 }
334
335 if (transitory)
336 lflags |= GPIO_TRANSITORY;
337
338 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
339 if (ret < 0) {
340 gpiod_put(desc);
341 return ERR_PTR(ret);
342 }
343
344 return desc;
345}
346EXPORT_SYMBOL_GPL(gpiod_get_from_of_node);
347
348/*
349 * The SPI GPIO bindings happened before we managed to establish that GPIO
350 * properties should be named "foo-gpios" so we have this special kludge for
351 * them.
352 */
353static struct gpio_desc *of_find_spi_gpio(struct device *dev, const char *con_id,
354 enum of_gpio_flags *of_flags)
355{
356 char prop_name[32]; /* 32 is max size of property name */
357 struct device_node *np = dev->of_node;
358 struct gpio_desc *desc;
359
360 /*
361 * Hopefully the compiler stubs the rest of the function if this
362 * is false.
363 */
364 if (!IS_ENABLED(CONFIG_SPI_MASTER))
365 return ERR_PTR(-ENOENT);
366
367 /* Allow this specifically for "spi-gpio" devices */
368 if (!of_device_is_compatible(np, "spi-gpio") || !con_id)
369 return ERR_PTR(-ENOENT);
370
371 /* Will be "gpio-sck", "gpio-mosi" or "gpio-miso" */
372 snprintf(prop_name, sizeof(prop_name), "%s-%s", "gpio", con_id);
373
374 desc = of_get_named_gpiod_flags(np, prop_name, 0, of_flags);
375 return desc;
376}
377
378/*
379 * The old Freescale bindings use simply "gpios" as name for the chip select
380 * lines rather than "cs-gpios" like all other SPI hardware. Account for this
381 * with a special quirk.
382 */
383static struct gpio_desc *of_find_spi_cs_gpio(struct device *dev,
384 const char *con_id,
385 unsigned int idx,
386 unsigned long *flags)
387{
388 struct device_node *np = dev->of_node;
389
390 if (!IS_ENABLED(CONFIG_SPI_MASTER))
391 return ERR_PTR(-ENOENT);
392
393 /* Allow this specifically for Freescale devices */
394 if (!of_device_is_compatible(np, "fsl,spi") &&
395 !of_device_is_compatible(np, "aeroflexgaisler,spictrl"))
396 return ERR_PTR(-ENOENT);
397 /* Allow only if asking for "cs-gpios" */
398 if (!con_id || strcmp(con_id, "cs"))
399 return ERR_PTR(-ENOENT);
400
401 /*
402 * While all other SPI controllers use "cs-gpios" the Freescale
403 * uses just "gpios" so translate to that when "cs-gpios" is
404 * requested.
405 */
406 return of_find_gpio(dev, NULL, idx, flags);
407}
408
409/*
410 * Some regulator bindings happened before we managed to establish that GPIO
411 * properties should be named "foo-gpios" so we have this special kludge for
412 * them.
413 */
414static struct gpio_desc *of_find_regulator_gpio(struct device *dev, const char *con_id,
415 enum of_gpio_flags *of_flags)
416{
417 /* These are the connection IDs we accept as legacy GPIO phandles */
418 const char *whitelist[] = {
419 "wlf,ldoena", /* Arizona */
420 "wlf,ldo1ena", /* WM8994 */
421 "wlf,ldo2ena", /* WM8994 */
422 };
423 struct device_node *np = dev->of_node;
424 struct gpio_desc *desc;
425 int i;
426
427 if (!IS_ENABLED(CONFIG_REGULATOR))
428 return ERR_PTR(-ENOENT);
429
430 if (!con_id)
431 return ERR_PTR(-ENOENT);
432
433 i = match_string(whitelist, ARRAY_SIZE(whitelist), con_id);
434 if (i < 0)
435 return ERR_PTR(-ENOENT);
436
437 desc = of_get_named_gpiod_flags(np, con_id, 0, of_flags);
438 return desc;
439}
440
441static struct gpio_desc *of_find_arizona_gpio(struct device *dev,
442 const char *con_id,
443 enum of_gpio_flags *of_flags)
444{
445 if (!IS_ENABLED(CONFIG_MFD_ARIZONA))
446 return ERR_PTR(-ENOENT);
447
448 if (!con_id || strcmp(con_id, "wlf,reset"))
449 return ERR_PTR(-ENOENT);
450
451 return of_get_named_gpiod_flags(dev->of_node, con_id, 0, of_flags);
452}
453
454struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
455 unsigned int idx, unsigned long *flags)
456{
457 char prop_name[32]; /* 32 is max size of property name */
458 enum of_gpio_flags of_flags;
459 struct gpio_desc *desc;
460 unsigned int i;
461
462 /* Try GPIO property "foo-gpios" and "foo-gpio" */
463 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
464 if (con_id)
465 snprintf(prop_name, sizeof(prop_name), "%s-%s", con_id,
466 gpio_suffixes[i]);
467 else
468 snprintf(prop_name, sizeof(prop_name), "%s",
469 gpio_suffixes[i]);
470
471 desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx,
472 &of_flags);
473
474 if (!IS_ERR(desc) || PTR_ERR(desc) != -ENOENT)
475 break;
476 }
477
478 if (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT) {
479 /* Special handling for SPI GPIOs if used */
480 desc = of_find_spi_gpio(dev, con_id, &of_flags);
481 }
482
483 if (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT) {
484 /* This quirk looks up flags and all */
485 desc = of_find_spi_cs_gpio(dev, con_id, idx, flags);
486 if (!IS_ERR(desc))
487 return desc;
488 }
489
490 if (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT) {
491 /* Special handling for regulator GPIOs if used */
492 desc = of_find_regulator_gpio(dev, con_id, &of_flags);
493 }
494
495 if (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT)
496 desc = of_find_arizona_gpio(dev, con_id, &of_flags);
497
498 if (IS_ERR(desc))
499 return desc;
500
501 if (of_flags & OF_GPIO_ACTIVE_LOW)
502 *flags |= GPIO_ACTIVE_LOW;
503
504 if (of_flags & OF_GPIO_SINGLE_ENDED) {
505 if (of_flags & OF_GPIO_OPEN_DRAIN)
506 *flags |= GPIO_OPEN_DRAIN;
507 else
508 *flags |= GPIO_OPEN_SOURCE;
509 }
510
511 if (of_flags & OF_GPIO_TRANSITORY)
512 *flags |= GPIO_TRANSITORY;
513
514 if (of_flags & OF_GPIO_PULL_UP)
515 *flags |= GPIO_PULL_UP;
516 if (of_flags & OF_GPIO_PULL_DOWN)
517 *flags |= GPIO_PULL_DOWN;
518
519 return desc;
520}
521
522/**
523 * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API
524 * @np: device node to get GPIO from
525 * @chip: GPIO chip whose hog is parsed
526 * @idx: Index of the GPIO to parse
527 * @name: GPIO line name
528 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
529 * of_find_gpio() or of_parse_own_gpio()
530 * @dflags: gpiod_flags - optional GPIO initialization flags
531 *
532 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
533 * value on the error condition.
534 */
535static struct gpio_desc *of_parse_own_gpio(struct device_node *np,
536 struct gpio_chip *chip,
537 unsigned int idx, const char **name,
538 unsigned long *lflags,
539 enum gpiod_flags *dflags)
540{
541 struct device_node *chip_np;
542 enum of_gpio_flags xlate_flags;
543 struct of_phandle_args gpiospec;
544 struct gpio_desc *desc;
545 unsigned int i;
546 u32 tmp;
547 int ret;
548
549 chip_np = chip->of_node;
550 if (!chip_np)
551 return ERR_PTR(-EINVAL);
552
553 xlate_flags = 0;
554 *lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
555 *dflags = 0;
556
557 ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp);
558 if (ret)
559 return ERR_PTR(ret);
560
561 gpiospec.np = chip_np;
562 gpiospec.args_count = tmp;
563
564 for (i = 0; i < tmp; i++) {
565 ret = of_property_read_u32_index(np, "gpios", idx * tmp + i,
566 &gpiospec.args[i]);
567 if (ret)
568 return ERR_PTR(ret);
569 }
570
571 desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, &xlate_flags);
572 if (IS_ERR(desc))
573 return desc;
574
575 if (xlate_flags & OF_GPIO_ACTIVE_LOW)
576 *lflags |= GPIO_ACTIVE_LOW;
577 if (xlate_flags & OF_GPIO_TRANSITORY)
578 *lflags |= GPIO_TRANSITORY;
579
580 if (of_property_read_bool(np, "input"))
581 *dflags |= GPIOD_IN;
582 else if (of_property_read_bool(np, "output-low"))
583 *dflags |= GPIOD_OUT_LOW;
584 else if (of_property_read_bool(np, "output-high"))
585 *dflags |= GPIOD_OUT_HIGH;
586 else {
587 pr_warn("GPIO line %d (%pOFn): no hogging state specified, bailing out\n",
588 desc_to_gpio(desc), np);
589 return ERR_PTR(-EINVAL);
590 }
591
592 if (name && of_property_read_string(np, "line-name", name))
593 *name = np->name;
594
595 return desc;
596}
597
598/**
599 * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions
600 * @chip: gpio chip to act on
601 *
602 * This is only used by of_gpiochip_add to request/set GPIO initial
603 * configuration.
604 * It returns error if it fails otherwise 0 on success.
605 */
606static int of_gpiochip_scan_gpios(struct gpio_chip *chip)
607{
608 struct gpio_desc *desc = NULL;
609 struct device_node *np;
610 const char *name;
611 unsigned long lflags;
612 enum gpiod_flags dflags;
613 unsigned int i;
614 int ret;
615
616 for_each_available_child_of_node(chip->of_node, np) {
617 if (!of_property_read_bool(np, "gpio-hog"))
618 continue;
619
620 for (i = 0;; i++) {
621 desc = of_parse_own_gpio(np, chip, i, &name, &lflags,
622 &dflags);
623 if (IS_ERR(desc))
624 break;
625
626 ret = gpiod_hog(desc, name, lflags, dflags);
627 if (ret < 0) {
628 of_node_put(np);
629 return ret;
630 }
631 }
632 }
633
634 return 0;
635}
636
637/**
638 * of_gpio_simple_xlate - translate gpiospec to the GPIO number and flags
639 * @gc: pointer to the gpio_chip structure
640 * @gpiospec: GPIO specifier as found in the device tree
641 * @flags: a flags pointer to fill in
642 *
643 * This is simple translation function, suitable for the most 1:1 mapped
644 * GPIO chips. This function performs only one sanity check: whether GPIO
645 * is less than ngpios (that is specified in the gpio_chip).
646 */
647static int of_gpio_simple_xlate(struct gpio_chip *gc,
648 const struct of_phandle_args *gpiospec,
649 u32 *flags)
650{
651 /*
652 * We're discouraging gpio_cells < 2, since that way you'll have to
653 * write your own xlate function (that will have to retrieve the GPIO
654 * number and the flags from a single gpio cell -- this is possible,
655 * but not recommended).
656 */
657 if (gc->of_gpio_n_cells < 2) {
658 WARN_ON(1);
659 return -EINVAL;
660 }
661
662 if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
663 return -EINVAL;
664
665 if (gpiospec->args[0] >= gc->ngpio)
666 return -EINVAL;
667
668 if (flags)
669 *flags = gpiospec->args[1];
670
671 return gpiospec->args[0];
672}
673
674/**
675 * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank)
676 * @np: device node of the GPIO chip
677 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure
678 * @data: driver data to store in the struct gpio_chip
679 *
680 * To use this function you should allocate and fill mm_gc with:
681 *
682 * 1) In the gpio_chip structure:
683 * - all the callbacks
684 * - of_gpio_n_cells
685 * - of_xlate callback (optional)
686 *
687 * 3) In the of_mm_gpio_chip structure:
688 * - save_regs callback (optional)
689 *
690 * If succeeded, this function will map bank's memory and will
691 * do all necessary work for you. Then you'll able to use .regs
692 * to manage GPIOs from the callbacks.
693 */
694int of_mm_gpiochip_add_data(struct device_node *np,
695 struct of_mm_gpio_chip *mm_gc,
696 void *data)
697{
698 int ret = -ENOMEM;
699 struct gpio_chip *gc = &mm_gc->gc;
700
701 gc->label = kasprintf(GFP_KERNEL, "%pOF", np);
702 if (!gc->label)
703 goto err0;
704
705 mm_gc->regs = of_iomap(np, 0);
706 if (!mm_gc->regs)
707 goto err1;
708
709 gc->base = -1;
710
711 if (mm_gc->save_regs)
712 mm_gc->save_regs(mm_gc);
713
714 mm_gc->gc.of_node = np;
715
716 ret = gpiochip_add_data(gc, data);
717 if (ret)
718 goto err2;
719
720 return 0;
721err2:
722 iounmap(mm_gc->regs);
723err1:
724 kfree(gc->label);
725err0:
726 pr_err("%pOF: GPIO chip registration failed with status %d\n", np, ret);
727 return ret;
728}
729EXPORT_SYMBOL_GPL(of_mm_gpiochip_add_data);
730
731/**
732 * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank)
733 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure
734 */
735void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc)
736{
737 struct gpio_chip *gc = &mm_gc->gc;
738
739 if (!mm_gc)
740 return;
741
742 gpiochip_remove(gc);
743 iounmap(mm_gc->regs);
744 kfree(gc->label);
745}
746EXPORT_SYMBOL_GPL(of_mm_gpiochip_remove);
747
748static void of_gpiochip_init_valid_mask(struct gpio_chip *chip)
749{
750 int len, i;
751 u32 start, count;
752 struct device_node *np = chip->of_node;
753
754 len = of_property_count_u32_elems(np, "gpio-reserved-ranges");
755 if (len < 0 || len % 2 != 0)
756 return;
757
758 for (i = 0; i < len; i += 2) {
759 of_property_read_u32_index(np, "gpio-reserved-ranges",
760 i, &start);
761 of_property_read_u32_index(np, "gpio-reserved-ranges",
762 i + 1, &count);
763 if (start >= chip->ngpio || start + count >= chip->ngpio)
764 continue;
765
766 bitmap_clear(chip->valid_mask, start, count);
767 }
768};
769
770#ifdef CONFIG_PINCTRL
771static int of_gpiochip_add_pin_range(struct gpio_chip *chip)
772{
773 struct device_node *np = chip->of_node;
774 struct of_phandle_args pinspec;
775 struct pinctrl_dev *pctldev;
776 int index = 0, ret;
777 const char *name;
778 static const char group_names_propname[] = "gpio-ranges-group-names";
779 struct property *group_names;
780
781 if (!np)
782 return 0;
783
784 group_names = of_find_property(np, group_names_propname, NULL);
785
786 for (;; index++) {
787 ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3,
788 index, &pinspec);
789 if (ret)
790 break;
791
792 pctldev = of_pinctrl_get(pinspec.np);
793 of_node_put(pinspec.np);
794 if (!pctldev)
795 return -EPROBE_DEFER;
796
797 if (pinspec.args[2]) {
798 if (group_names) {
799 of_property_read_string_index(np,
800 group_names_propname,
801 index, &name);
802 if (strlen(name)) {
803 pr_err("%pOF: Group name of numeric GPIO ranges must be the empty string.\n",
804 np);
805 break;
806 }
807 }
808 /* npins != 0: linear range */
809 ret = gpiochip_add_pin_range(chip,
810 pinctrl_dev_get_devname(pctldev),
811 pinspec.args[0],
812 pinspec.args[1],
813 pinspec.args[2]);
814 if (ret)
815 return ret;
816 } else {
817 /* npins == 0: special range */
818 if (pinspec.args[1]) {
819 pr_err("%pOF: Illegal gpio-range format.\n",
820 np);
821 break;
822 }
823
824 if (!group_names) {
825 pr_err("%pOF: GPIO group range requested but no %s property.\n",
826 np, group_names_propname);
827 break;
828 }
829
830 ret = of_property_read_string_index(np,
831 group_names_propname,
832 index, &name);
833 if (ret)
834 break;
835
836 if (!strlen(name)) {
837 pr_err("%pOF: Group name of GPIO group range cannot be the empty string.\n",
838 np);
839 break;
840 }
841
842 ret = gpiochip_add_pingroup_range(chip, pctldev,
843 pinspec.args[0], name);
844 if (ret)
845 return ret;
846 }
847 }
848
849 return 0;
850}
851
852#else
853static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; }
854#endif
855
856int of_gpiochip_add(struct gpio_chip *chip)
857{
858 int ret;
859
860 if (!chip->of_node)
861 return 0;
862
863 if (!chip->of_xlate) {
864 chip->of_gpio_n_cells = 2;
865 chip->of_xlate = of_gpio_simple_xlate;
866 }
867
868 if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS)
869 return -EINVAL;
870
871 of_gpiochip_init_valid_mask(chip);
872
873 ret = of_gpiochip_add_pin_range(chip);
874 if (ret)
875 return ret;
876
877 /* If the chip defines names itself, these take precedence */
878 if (!chip->names)
879 devprop_gpiochip_set_names(chip,
880 of_fwnode_handle(chip->of_node));
881
882 of_node_get(chip->of_node);
883
884 ret = of_gpiochip_scan_gpios(chip);
885 if (ret) {
886 of_node_put(chip->of_node);
887 gpiochip_remove_pin_ranges(chip);
888 }
889
890 return ret;
891}
892
893void of_gpiochip_remove(struct gpio_chip *chip)
894{
895 gpiochip_remove_pin_ranges(chip);
896 of_node_put(chip->of_node);
897}