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v4.6
  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}
v4.10.11
  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
 29static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip, void *data)
 30{
 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;
 35}
 36
 37static struct gpio_chip *of_find_gpiochip_by_xlate(
 38					struct of_phandle_args *gpiospec)
 39{
 40	return gpiochip_find(gpiospec, of_gpiochip_match_node_and_xlate);
 41}
 42
 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)
 46{
 
 47	int ret;
 48
 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);
 
 57}
 58
 59/**
 60 * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API
 61 * @np:		device node to get GPIO from
 62 * @propname:	property name containing gpio specifier(s)
 63 * @index:	index of the GPIO
 64 * @flags:	a flags pointer to fill in
 65 *
 66 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
 67 * value on the error condition. If @flags is not NULL the function also fills
 68 * in flags for the GPIO.
 69 */
 70struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
 71		     const char *propname, int index, enum of_gpio_flags *flags)
 72{
 73	struct of_phandle_args gpiospec;
 74	struct gpio_chip *chip;
 75	struct gpio_desc *desc;
 
 
 
 
 76	int ret;
 77
 
 
 
 
 78	ret = of_parse_phandle_with_args(np, propname, "#gpio-cells", index,
 79					 &gpiospec);
 80	if (ret) {
 81		pr_debug("%s: can't parse '%s' property of node '%s[%d]'\n",
 82			__func__, propname, np->full_name, index);
 83		return ERR_PTR(ret);
 84	}
 85
 86	chip = of_find_gpiochip_by_xlate(&gpiospec);
 87	if (!chip) {
 88		desc = ERR_PTR(-EPROBE_DEFER);
 89		goto out;
 90	}
 91
 92	desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, flags);
 93	if (IS_ERR(desc))
 94		goto out;
 95
 
 96	pr_debug("%s: parsed '%s' property of node '%s[%d]' - status (%d)\n",
 97		 __func__, propname, np->full_name, index,
 98		 PTR_ERR_OR_ZERO(desc));
 99
100out:
101	of_node_put(gpiospec.np);
102
103	return desc;
104}
105
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
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) {
150		if (of_flags & OF_GPIO_ACTIVE_LOW)
151			*flags |= GPIO_OPEN_DRAIN;
152		else
153			*flags |= GPIO_OPEN_SOURCE;
154	}
155
156	return desc;
157}
158
159/**
160 * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API
161 * @np:		device node to get GPIO from
162 * @chip:	GPIO chip whose hog is parsed
163 * @name:	GPIO line name
164 * @lflags:	gpio_lookup_flags - returned from of_find_gpio() or
165 *		of_parse_own_gpio()
166 * @dflags:	gpiod_flags - optional GPIO initialization flags
167 *
168 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
169 * value on the error condition.
170 */
171static struct gpio_desc *of_parse_own_gpio(struct device_node *np,
172					   struct gpio_chip *chip,
173					   const char **name,
174					   enum gpio_lookup_flags *lflags,
175					   enum gpiod_flags *dflags)
176{
177	struct device_node *chip_np;
178	enum of_gpio_flags xlate_flags;
179	struct of_phandle_args gpiospec;
180	struct gpio_desc *desc;
 
181	u32 tmp;
182	int ret;
183
184	chip_np = chip->of_node;
185	if (!chip_np)
186		return ERR_PTR(-EINVAL);
187
188	xlate_flags = 0;
189	*lflags = 0;
190	*dflags = 0;
191
192	ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp);
193	if (ret)
194		return ERR_PTR(ret);
195
196	gpiospec.np = chip_np;
197	gpiospec.args_count = tmp;
198
199	ret = of_property_read_u32_array(np, "gpios", gpiospec.args, tmp);
200	if (ret)
201		return ERR_PTR(ret);
 
 
 
 
 
202
203	desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, &xlate_flags);
204	if (IS_ERR(desc))
205		return desc;
 
 
 
 
206
207	if (xlate_flags & OF_GPIO_ACTIVE_LOW)
208		*lflags |= GPIO_ACTIVE_LOW;
209
210	if (of_property_read_bool(np, "input"))
211		*dflags |= GPIOD_IN;
212	else if (of_property_read_bool(np, "output-low"))
213		*dflags |= GPIOD_OUT_LOW;
214	else if (of_property_read_bool(np, "output-high"))
215		*dflags |= GPIOD_OUT_HIGH;
216	else {
217		pr_warn("GPIO line %d (%s): no hogging state specified, bailing out\n",
218			desc_to_gpio(desc), np->name);
219		return ERR_PTR(-EINVAL);
220	}
221
222	if (name && of_property_read_string(np, "line-name", name))
223		*name = np->name;
224
225	return desc;
226}
227
228/**
229 * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions
230 * @chip:	gpio chip to act on
231 *
232 * This is only used by of_gpiochip_add to request/set GPIO initial
233 * configuration.
234 * It retures error if it fails otherwise 0 on success.
235 */
236static int of_gpiochip_scan_gpios(struct gpio_chip *chip)
237{
238	struct gpio_desc *desc = NULL;
239	struct device_node *np;
240	const char *name;
241	enum gpio_lookup_flags lflags;
242	enum gpiod_flags dflags;
243	int ret;
244
245	for_each_available_child_of_node(chip->of_node, np) {
246		if (!of_property_read_bool(np, "gpio-hog"))
247			continue;
248
249		desc = of_parse_own_gpio(np, chip, &name, &lflags, &dflags);
250		if (IS_ERR(desc))
251			continue;
252
253		ret = gpiod_hog(desc, name, lflags, dflags);
254		if (ret < 0) {
255			of_node_put(np);
256			return ret;
257		}
258	}
259
260	return 0;
261}
262
263/**
264 * of_gpio_simple_xlate - translate gpio_spec to the GPIO number and flags
265 * @gc:		pointer to the gpio_chip structure
266 * @np:		device node of the GPIO chip
267 * @gpio_spec:	gpio specifier as found in the device tree
268 * @flags:	a flags pointer to fill in
269 *
270 * This is simple translation function, suitable for the most 1:1 mapped
271 * gpio chips. This function performs only one sanity check: whether gpio
272 * is less than ngpios (that is specified in the gpio_chip).
273 */
274int of_gpio_simple_xlate(struct gpio_chip *gc,
275			 const struct of_phandle_args *gpiospec, u32 *flags)
276{
277	/*
278	 * We're discouraging gpio_cells < 2, since that way you'll have to
279	 * write your own xlate function (that will have to retrieve the GPIO
280	 * number and the flags from a single gpio cell -- this is possible,
281	 * but not recommended).
282	 */
283	if (gc->of_gpio_n_cells < 2) {
284		WARN_ON(1);
285		return -EINVAL;
286	}
287
288	if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
289		return -EINVAL;
290
291	if (gpiospec->args[0] >= gc->ngpio)
292		return -EINVAL;
293
294	if (flags)
295		*flags = gpiospec->args[1];
296
297	return gpiospec->args[0];
298}
299EXPORT_SYMBOL(of_gpio_simple_xlate);
300
301/**
302 * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank)
303 * @np:		device node of the GPIO chip
304 * @mm_gc:	pointer to the of_mm_gpio_chip allocated structure
305 * @data:	driver data to store in the struct gpio_chip
306 *
307 * To use this function you should allocate and fill mm_gc with:
308 *
309 * 1) In the gpio_chip structure:
310 *    - all the callbacks
311 *    - of_gpio_n_cells
312 *    - of_xlate callback (optional)
313 *
314 * 3) In the of_mm_gpio_chip structure:
315 *    - save_regs callback (optional)
316 *
317 * If succeeded, this function will map bank's memory and will
318 * do all necessary work for you. Then you'll able to use .regs
319 * to manage GPIOs from the callbacks.
320 */
321int of_mm_gpiochip_add_data(struct device_node *np,
322			    struct of_mm_gpio_chip *mm_gc,
323			    void *data)
324{
325	int ret = -ENOMEM;
326	struct gpio_chip *gc = &mm_gc->gc;
327
328	gc->label = kstrdup(np->full_name, GFP_KERNEL);
329	if (!gc->label)
330		goto err0;
331
332	mm_gc->regs = of_iomap(np, 0);
333	if (!mm_gc->regs)
334		goto err1;
335
336	gc->base = -1;
337
338	if (mm_gc->save_regs)
339		mm_gc->save_regs(mm_gc);
340
341	mm_gc->gc.of_node = np;
342
343	ret = gpiochip_add_data(gc, data);
344	if (ret)
345		goto err2;
346
347	return 0;
348err2:
349	iounmap(mm_gc->regs);
350err1:
351	kfree(gc->label);
352err0:
353	pr_err("%s: GPIO chip registration failed with status %d\n",
354	       np->full_name, ret);
355	return ret;
356}
357EXPORT_SYMBOL(of_mm_gpiochip_add_data);
358
359/**
360 * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank)
361 * @mm_gc:	pointer to the of_mm_gpio_chip allocated structure
362 */
363void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc)
364{
365	struct gpio_chip *gc = &mm_gc->gc;
366
367	if (!mm_gc)
368		return;
369
370	gpiochip_remove(gc);
371	iounmap(mm_gc->regs);
372	kfree(gc->label);
373}
374EXPORT_SYMBOL(of_mm_gpiochip_remove);
375
376#ifdef CONFIG_PINCTRL
377static int of_gpiochip_add_pin_range(struct gpio_chip *chip)
378{
379	struct device_node *np = chip->of_node;
380	struct of_phandle_args pinspec;
381	struct pinctrl_dev *pctldev;
382	int index = 0, ret;
383	const char *name;
384	static const char group_names_propname[] = "gpio-ranges-group-names";
385	struct property *group_names;
386
387	if (!np)
388		return 0;
389
390	group_names = of_find_property(np, group_names_propname, NULL);
391
392	for (;; index++) {
393		ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3,
394				index, &pinspec);
395		if (ret)
396			break;
397
398		pctldev = of_pinctrl_get(pinspec.np);
399		of_node_put(pinspec.np);
400		if (!pctldev)
401			return -EPROBE_DEFER;
402
403		if (pinspec.args[2]) {
404			if (group_names) {
405				of_property_read_string_index(np,
406						group_names_propname,
407						index, &name);
408				if (strlen(name)) {
409					pr_err("%s: Group name of numeric GPIO ranges must be the empty string.\n",
410						np->full_name);
411					break;
412				}
413			}
414			/* npins != 0: linear range */
415			ret = gpiochip_add_pin_range(chip,
416					pinctrl_dev_get_devname(pctldev),
417					pinspec.args[0],
418					pinspec.args[1],
419					pinspec.args[2]);
420			if (ret)
421				return ret;
422		} else {
423			/* npins == 0: special range */
424			if (pinspec.args[1]) {
425				pr_err("%s: Illegal gpio-range format.\n",
426					np->full_name);
427				break;
428			}
429
430			if (!group_names) {
431				pr_err("%s: GPIO group range requested but no %s property.\n",
432					np->full_name, group_names_propname);
433				break;
434			}
435
436			ret = of_property_read_string_index(np,
437						group_names_propname,
438						index, &name);
439			if (ret)
440				break;
441
442			if (!strlen(name)) {
443				pr_err("%s: Group name of GPIO group range cannot be the empty string.\n",
444				np->full_name);
445				break;
446			}
447
448			ret = gpiochip_add_pingroup_range(chip, pctldev,
449						pinspec.args[0], name);
450			if (ret)
451				return ret;
452		}
453	}
454
455	return 0;
456}
457
458#else
459static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; }
460#endif
461
462int of_gpiochip_add(struct gpio_chip *chip)
463{
464	int status;
465
466	if ((!chip->of_node) && (chip->parent))
467		chip->of_node = chip->parent->of_node;
468
469	if (!chip->of_node)
470		return 0;
471
472	if (!chip->of_xlate) {
473		chip->of_gpio_n_cells = 2;
474		chip->of_xlate = of_gpio_simple_xlate;
475	}
476
477	if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS)
478		return -EINVAL;
479
480	status = of_gpiochip_add_pin_range(chip);
481	if (status)
482		return status;
483
484	/* If the chip defines names itself, these take precedence */
485	if (!chip->names)
486		devprop_gpiochip_set_names(chip);
487
488	of_node_get(chip->of_node);
489
490	return of_gpiochip_scan_gpios(chip);
491}
492
493void of_gpiochip_remove(struct gpio_chip *chip)
494{
495	gpiochip_remove_pin_ranges(chip);
496	of_node_put(chip->of_node);
497}