xref: /linux/drivers/gpio/gpiolib-of.c (revision aacc73ceeb8bf664426f0e53db2778a59325bd9f)
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/io.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/of_address.h>
17 #include <linux/of_gpio.h>
18 #include <linux/pinctrl/pinctrl.h>
19 #include <linux/slab.h>
20 #include <linux/string.h>
21 
22 #include <linux/gpio/consumer.h>
23 #include <linux/gpio/machine.h>
24 
25 #include "gpiolib.h"
26 #include "gpiolib-of.h"
27 
28 /*
29  * This is Linux-specific flags. By default controllers' and Linux' mapping
30  * match, but GPIO controllers are free to translate their own flags to
31  * Linux-specific in their .xlate callback. Though, 1:1 mapping is recommended.
32  */
33 enum of_gpio_flags {
34 	OF_GPIO_ACTIVE_LOW = 0x1,
35 	OF_GPIO_SINGLE_ENDED = 0x2,
36 	OF_GPIO_OPEN_DRAIN = 0x4,
37 	OF_GPIO_TRANSITORY = 0x8,
38 	OF_GPIO_PULL_UP = 0x10,
39 	OF_GPIO_PULL_DOWN = 0x20,
40 	OF_GPIO_PULL_DISABLE = 0x40,
41 };
42 
43 /**
44  * of_gpio_named_count() - Count GPIOs for a device
45  * @np:		device node to count GPIOs for
46  * @propname:	property name containing gpio specifier(s)
47  *
48  * The function returns the count of GPIOs specified for a node.
49  * NOTE: The empty GPIO specifiers count too.
50  *
51  * Returns:
52  * Either number of GPIOs defined in the property, or
53  * *  %-EINVAL for an incorrectly formed "gpios" property, or
54  * *  %-ENOENT for a missing "gpios" property.
55  *
56  * Example::
57  *
58  *     gpios = <0
59  *              &gpio1 1 2
60  *              0
61  *              &gpio2 3 4>;
62  *
63  * The above example defines four GPIOs, two of which are not specified.
64  * This function will return '4'
65  */
of_gpio_named_count(const struct device_node * np,const char * propname)66 static int of_gpio_named_count(const struct device_node *np,
67 			       const char *propname)
68 {
69 	return of_count_phandle_with_args(np, propname, "#gpio-cells");
70 }
71 
72 /**
73  * of_gpio_spi_cs_get_count() - special GPIO counting for SPI
74  * @np:    Consuming device node
75  * @con_id: Function within the GPIO consumer
76  *
77  * Some elder GPIO controllers need special quirks. Currently we handle
78  * the Freescale and PPC GPIO controller with bindings that doesn't use the
79  * established "cs-gpios" for chip selects but instead rely on
80  * "gpios" for the chip select lines. If we detect this, we redirect
81  * the counting of "cs-gpios" to count "gpios" transparent to the
82  * driver.
83  *
84  * Returns:
85  * Either number of GPIOs defined in the property, or
86  * *  %-EINVAL for an incorrectly formed "gpios" property, or
87  * *  %-ENOENT for a missing "gpios" property.
88  */
of_gpio_spi_cs_get_count(const struct device_node * np,const char * con_id)89 static int of_gpio_spi_cs_get_count(const struct device_node *np,
90 				    const char *con_id)
91 {
92 	if (!IS_ENABLED(CONFIG_SPI_MASTER))
93 		return 0;
94 	if (!con_id || strcmp(con_id, "cs"))
95 		return 0;
96 	if (!of_device_is_compatible(np, "fsl,spi") &&
97 	    !of_device_is_compatible(np, "aeroflexgaisler,spictrl") &&
98 	    !of_device_is_compatible(np, "ibm,ppc4xx-spi"))
99 		return 0;
100 	return of_gpio_named_count(np, "gpios");
101 }
102 
of_gpio_count(const struct fwnode_handle * fwnode,const char * con_id)103 int of_gpio_count(const struct fwnode_handle *fwnode, const char *con_id)
104 {
105 	const struct device_node *np = to_of_node(fwnode);
106 	int ret;
107 	char propname[32];
108 
109 	ret = of_gpio_spi_cs_get_count(np, con_id);
110 	if (ret > 0)
111 		return ret;
112 
113 	for_each_gpio_property_name(propname, con_id) {
114 		ret = of_gpio_named_count(np, propname);
115 		if (ret > 0)
116 			break;
117 	}
118 	return ret ? ret : -ENOENT;
119 }
120 
of_gpiochip_match_node_and_xlate(struct gpio_chip * chip,const void * data)121 static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip,
122 					    const void *data)
123 {
124 	const struct of_phandle_args *gpiospec = data;
125 
126 	return device_match_of_node(&chip->gpiodev->dev, gpiospec->np) &&
127 				chip->of_xlate &&
128 				chip->of_xlate(chip, gpiospec, NULL) >= 0;
129 }
130 
131 static struct gpio_device *
of_find_gpio_device_by_xlate(const struct of_phandle_args * gpiospec)132 of_find_gpio_device_by_xlate(const struct of_phandle_args *gpiospec)
133 {
134 	return gpio_device_find(gpiospec, of_gpiochip_match_node_and_xlate);
135 }
136 
of_xlate_and_get_gpiod_flags(struct gpio_chip * chip,struct of_phandle_args * gpiospec,enum of_gpio_flags * flags)137 static struct gpio_desc *of_xlate_and_get_gpiod_flags(struct gpio_chip *chip,
138 					struct of_phandle_args *gpiospec,
139 					enum of_gpio_flags *flags)
140 {
141 	int ret;
142 
143 	if (chip->of_gpio_n_cells != gpiospec->args_count)
144 		return ERR_PTR(-EINVAL);
145 
146 	ret = chip->of_xlate(chip, gpiospec, flags);
147 	if (ret < 0)
148 		return ERR_PTR(ret);
149 
150 	return gpiochip_get_desc(chip, ret);
151 }
152 
153 /*
154  * Overrides stated polarity of a gpio line and warns when there is a
155  * discrepancy.
156  */
of_gpio_quirk_polarity(const struct device_node * np,bool active_high,enum of_gpio_flags * flags)157 static void of_gpio_quirk_polarity(const struct device_node *np,
158 				   bool active_high,
159 				   enum of_gpio_flags *flags)
160 {
161 	if (active_high) {
162 		if (*flags & OF_GPIO_ACTIVE_LOW) {
163 			pr_warn("%s GPIO handle specifies active low - ignored\n",
164 				of_node_full_name(np));
165 			*flags &= ~OF_GPIO_ACTIVE_LOW;
166 		}
167 	} else {
168 		if (!(*flags & OF_GPIO_ACTIVE_LOW))
169 			pr_info("%s enforce active low on GPIO handle\n",
170 				of_node_full_name(np));
171 		*flags |= OF_GPIO_ACTIVE_LOW;
172 	}
173 }
174 
175 /*
176  * This quirk does static polarity overrides in cases where existing
177  * DTS specified incorrect polarity.
178  */
of_gpio_try_fixup_polarity(const struct device_node * np,const char * propname,enum of_gpio_flags * flags)179 static void of_gpio_try_fixup_polarity(const struct device_node *np,
180 				       const char *propname,
181 				       enum of_gpio_flags *flags)
182 {
183 	static const struct {
184 		const char *compatible;
185 		const char *propname;
186 		bool active_high;
187 	} gpios[] = {
188 #if IS_ENABLED(CONFIG_LCD_HX8357)
189 		/*
190 		 * Himax LCD controllers used incorrectly named
191 		 * "gpios-reset" property and also specified wrong
192 		 * polarity.
193 		 */
194 		{ "himax,hx8357",	"gpios-reset",	false },
195 		{ "himax,hx8369",	"gpios-reset",	false },
196 #endif
197 #if IS_ENABLED(CONFIG_MTD_NAND_JZ4780)
198 		/*
199 		 * The rb-gpios semantics was undocumented and qi,lb60 (along with
200 		 * the ingenic driver) got it wrong. The active state encodes the
201 		 * NAND ready state, which is high level. Since there's no signal
202 		 * inverter on this board, it should be active-high. Let's fix that
203 		 * here for older DTs so we can re-use the generic nand_gpio_waitrdy()
204 		 * helper, and be consistent with what other drivers do.
205 		 */
206 		{ "qi,lb60",		"rb-gpios",	true },
207 #endif
208 #if IS_ENABLED(CONFIG_IEEE802154_CA8210)
209 		/*
210 		 * According to the datasheet, the NRST pin 27 is an active-low
211 		 * signal. However, the device tree schema and admittedly
212 		 * the out-of-tree implementations have been used for a long
213 		 * time incorrectly by describing reset GPIO as active-high.
214 		 */
215 		{ "cascoda,ca8210",	"reset-gpio",	false },
216 #endif
217 #if IS_ENABLED(CONFIG_PCI_LANTIQ)
218 		/*
219 		 * According to the PCI specification, the RST# pin is an
220 		 * active-low signal. However, most of the device trees that
221 		 * have been widely used for a long time incorrectly describe
222 		 * reset GPIO as active-high, and were also using wrong name
223 		 * for the property.
224 		 */
225 		{ "lantiq,pci-xway",	"gpio-reset",	false },
226 #endif
227 #if IS_ENABLED(CONFIG_REGULATOR_S5M8767)
228 		/*
229 		 * According to S5M8767, the DVS and DS pin are
230 		 * active-high signals. However, exynos5250-spring.dts use
231 		 * active-low setting.
232 		 */
233 		{ "samsung,s5m8767-pmic", "s5m8767,pmic-buck-dvs-gpios", true },
234 		{ "samsung,s5m8767-pmic", "s5m8767,pmic-buck-ds-gpios", true },
235 #endif
236 #if IS_ENABLED(CONFIG_TOUCHSCREEN_TSC2005)
237 		/*
238 		 * DTS for Nokia N900 incorrectly specified "active high"
239 		 * polarity for the reset line, while the chip actually
240 		 * treats it as "active low".
241 		 */
242 		{ "ti,tsc2005",		"reset-gpios",	false },
243 #endif
244 	};
245 	unsigned int i;
246 
247 	for (i = 0; i < ARRAY_SIZE(gpios); i++) {
248 		if (of_device_is_compatible(np, gpios[i].compatible) &&
249 		    !strcmp(propname, gpios[i].propname)) {
250 			of_gpio_quirk_polarity(np, gpios[i].active_high, flags);
251 			break;
252 		}
253 	}
254 }
255 
of_gpio_set_polarity_by_property(const struct device_node * np,const char * propname,enum of_gpio_flags * flags)256 static void of_gpio_set_polarity_by_property(const struct device_node *np,
257 					     const char *propname,
258 					     enum of_gpio_flags *flags)
259 {
260 	const struct device_node *np_compat = np;
261 	const struct device_node *np_propname = np;
262 	static const struct {
263 		const char *compatible;
264 		const char *gpio_propname;
265 		const char *polarity_propname;
266 	} gpios[] = {
267 #if IS_ENABLED(CONFIG_FEC)
268 		/* Freescale Fast Ethernet Controller */
269 		{ "fsl,imx25-fec",   "phy-reset-gpios", "phy-reset-active-high" },
270 		{ "fsl,imx27-fec",   "phy-reset-gpios", "phy-reset-active-high" },
271 		{ "fsl,imx28-fec",   "phy-reset-gpios", "phy-reset-active-high" },
272 		{ "fsl,imx6q-fec",   "phy-reset-gpios", "phy-reset-active-high" },
273 		{ "fsl,mvf600-fec",  "phy-reset-gpios", "phy-reset-active-high" },
274 		{ "fsl,imx6sx-fec",  "phy-reset-gpios", "phy-reset-active-high" },
275 		{ "fsl,imx6ul-fec",  "phy-reset-gpios", "phy-reset-active-high" },
276 		{ "fsl,imx8mq-fec",  "phy-reset-gpios", "phy-reset-active-high" },
277 		{ "fsl,imx8qm-fec",  "phy-reset-gpios", "phy-reset-active-high" },
278 		{ "fsl,s32v234-fec", "phy-reset-gpios", "phy-reset-active-high" },
279 #endif
280 #if IS_ENABLED(CONFIG_MMC_ATMELMCI)
281 		{ "atmel,hsmci",       "cd-gpios",     "cd-inverted" },
282 #endif
283 #if IS_ENABLED(CONFIG_PCI_IMX6)
284 		{ "fsl,imx6q-pcie",  "reset-gpio", "reset-gpio-active-high" },
285 		{ "fsl,imx6sx-pcie", "reset-gpio", "reset-gpio-active-high" },
286 		{ "fsl,imx6qp-pcie", "reset-gpio", "reset-gpio-active-high" },
287 		{ "fsl,imx7d-pcie",  "reset-gpio", "reset-gpio-active-high" },
288 		{ "fsl,imx8mq-pcie", "reset-gpio", "reset-gpio-active-high" },
289 		{ "fsl,imx8mm-pcie", "reset-gpio", "reset-gpio-active-high" },
290 		{ "fsl,imx8mp-pcie", "reset-gpio", "reset-gpio-active-high" },
291 #endif
292 
293 		/*
294 		 * The regulator GPIO handles are specified such that the
295 		 * presence or absence of "enable-active-high" solely controls
296 		 * the polarity of the GPIO line. Any phandle flags must
297 		 * be actively ignored.
298 		 */
299 #if IS_ENABLED(CONFIG_REGULATOR_FIXED_VOLTAGE)
300 		{ "regulator-fixed",   "gpios",        "enable-active-high" },
301 		{ "regulator-fixed",   "gpio",         "enable-active-high" },
302 		{ "reg-fixed-voltage", "gpios",        "enable-active-high" },
303 		{ "reg-fixed-voltage", "gpio",         "enable-active-high" },
304 #endif
305 #if IS_ENABLED(CONFIG_REGULATOR_GPIO)
306 		{ "regulator-gpio",    "enable-gpio",  "enable-active-high" },
307 		{ "regulator-gpio",    "enable-gpios", "enable-active-high" },
308 #endif
309 	};
310 	unsigned int i;
311 	bool active_high;
312 
313 #if IS_ENABLED(CONFIG_MMC_ATMELMCI)
314 	/*
315 	 * The Atmel HSMCI has compatible property in the parent node and
316 	 * gpio property in a child node
317 	 */
318 	if (of_device_is_compatible(np->parent, "atmel,hsmci")) {
319 		np_compat = np->parent;
320 		np_propname = np;
321 	}
322 #endif
323 
324 	for (i = 0; i < ARRAY_SIZE(gpios); i++) {
325 		if (of_device_is_compatible(np_compat, gpios[i].compatible) &&
326 		    !strcmp(propname, gpios[i].gpio_propname)) {
327 			active_high = of_property_read_bool(np_propname,
328 						gpios[i].polarity_propname);
329 			of_gpio_quirk_polarity(np, active_high, flags);
330 			break;
331 		}
332 	}
333 }
334 
of_gpio_flags_quirks(const struct device_node * np,const char * propname,enum of_gpio_flags * flags,int index)335 static void of_gpio_flags_quirks(const struct device_node *np,
336 				 const char *propname,
337 				 enum of_gpio_flags *flags,
338 				 int index)
339 {
340 	of_gpio_try_fixup_polarity(np, propname, flags);
341 	of_gpio_set_polarity_by_property(np, propname, flags);
342 
343 	/*
344 	 * Legacy open drain handling for fixed voltage regulators.
345 	 */
346 	if (IS_ENABLED(CONFIG_REGULATOR) &&
347 	    of_device_is_compatible(np, "reg-fixed-voltage") &&
348 	    of_property_read_bool(np, "gpio-open-drain")) {
349 		*flags |= (OF_GPIO_SINGLE_ENDED | OF_GPIO_OPEN_DRAIN);
350 		pr_info("%s uses legacy open drain flag - update the DTS if you can\n",
351 			of_node_full_name(np));
352 	}
353 
354 	/*
355 	 * Legacy handling of SPI active high chip select. If we have a
356 	 * property named "cs-gpios" we need to inspect the child node
357 	 * to determine if the flags should have inverted semantics.
358 	 */
359 	if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") &&
360 	    of_property_present(np, "cs-gpios")) {
361 		u32 cs;
362 		int ret;
363 
364 		for_each_child_of_node_scoped(np, child) {
365 			ret = of_property_read_u32(child, "reg", &cs);
366 			if (ret)
367 				continue;
368 			if (cs == index) {
369 				/*
370 				 * SPI children have active low chip selects
371 				 * by default. This can be specified negatively
372 				 * by just omitting "spi-cs-high" in the
373 				 * device node, or actively by tagging on
374 				 * GPIO_ACTIVE_LOW as flag in the device
375 				 * tree. If the line is simultaneously
376 				 * tagged as active low in the device tree
377 				 * and has the "spi-cs-high" set, we get a
378 				 * conflict and the "spi-cs-high" flag will
379 				 * take precedence.
380 				 */
381 				bool active_high = of_property_read_bool(child,
382 								"spi-cs-high");
383 				of_gpio_quirk_polarity(child, active_high,
384 						       flags);
385 				break;
386 			}
387 		}
388 	}
389 
390 	/* Legacy handling of stmmac's active-low PHY reset line */
391 	if (IS_ENABLED(CONFIG_STMMAC_ETH) &&
392 	    !strcmp(propname, "snps,reset-gpio") &&
393 	    of_property_read_bool(np, "snps,reset-active-low"))
394 		*flags |= OF_GPIO_ACTIVE_LOW;
395 }
396 
397 /**
398  * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API
399  * @np:		device node to get GPIO from
400  * @propname:	property name containing gpio specifier(s)
401  * @index:	index of the GPIO
402  * @flags:	a flags pointer to fill in
403  *
404  * Returns:
405  * GPIO descriptor to use with Linux GPIO API, or one of the errno
406  * value on the error condition. If @flags is not NULL the function also fills
407  * in flags for the GPIO.
408  */
of_get_named_gpiod_flags(const struct device_node * np,const char * propname,int index,enum of_gpio_flags * flags)409 static struct gpio_desc *of_get_named_gpiod_flags(const struct device_node *np,
410 		     const char *propname, int index, enum of_gpio_flags *flags)
411 {
412 	struct of_phandle_args gpiospec;
413 	struct gpio_desc *desc;
414 	int ret;
415 
416 	ret = of_parse_phandle_with_args_map(np, propname, "gpio", index,
417 					     &gpiospec);
418 	if (ret) {
419 		pr_debug("%s: can't parse '%s' property of node '%pOF[%d]'\n",
420 			__func__, propname, np, index);
421 		return ERR_PTR(ret);
422 	}
423 
424 	struct gpio_device *gdev __free(gpio_device_put) =
425 				of_find_gpio_device_by_xlate(&gpiospec);
426 	if (!gdev) {
427 		desc = ERR_PTR(-EPROBE_DEFER);
428 		goto out;
429 	}
430 
431 	desc = of_xlate_and_get_gpiod_flags(gpio_device_get_chip(gdev),
432 					    &gpiospec, flags);
433 	if (IS_ERR(desc))
434 		goto out;
435 
436 	if (flags)
437 		of_gpio_flags_quirks(np, propname, flags, index);
438 
439 	pr_debug("%s: parsed '%s' property of node '%pOF[%d]' - status (%d)\n",
440 		 __func__, propname, np, index,
441 		 PTR_ERR_OR_ZERO(desc));
442 
443 out:
444 	of_node_put(gpiospec.np);
445 
446 	return desc;
447 }
448 
449 /**
450  * of_get_named_gpio() - Get a GPIO number to use with GPIO API
451  * @np:		device node to get GPIO from
452  * @propname:	Name of property containing gpio specifier(s)
453  * @index:	index of the GPIO
454  *
455  * **DEPRECATED** This function is deprecated and must not be used in new code.
456  *
457  * Returns:
458  * GPIO number to use with Linux generic GPIO API, or one of the errno
459  * value on the error condition.
460  */
of_get_named_gpio(const struct device_node * np,const char * propname,int index)461 int of_get_named_gpio(const struct device_node *np, const char *propname,
462 		      int index)
463 {
464 	struct gpio_desc *desc;
465 
466 	desc = of_get_named_gpiod_flags(np, propname, index, NULL);
467 
468 	if (IS_ERR(desc))
469 		return PTR_ERR(desc);
470 	else
471 		return desc_to_gpio(desc);
472 }
473 EXPORT_SYMBOL_GPL(of_get_named_gpio);
474 
475 /* Converts gpio_lookup_flags into bitmask of GPIO_* values */
of_convert_gpio_flags(enum of_gpio_flags flags)476 static unsigned long of_convert_gpio_flags(enum of_gpio_flags flags)
477 {
478 	unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
479 
480 	if (flags & OF_GPIO_ACTIVE_LOW)
481 		lflags |= GPIO_ACTIVE_LOW;
482 
483 	if (flags & OF_GPIO_SINGLE_ENDED) {
484 		if (flags & OF_GPIO_OPEN_DRAIN)
485 			lflags |= GPIO_OPEN_DRAIN;
486 		else
487 			lflags |= GPIO_OPEN_SOURCE;
488 	}
489 
490 	if (flags & OF_GPIO_TRANSITORY)
491 		lflags |= GPIO_TRANSITORY;
492 
493 	if (flags & OF_GPIO_PULL_UP)
494 		lflags |= GPIO_PULL_UP;
495 
496 	if (flags & OF_GPIO_PULL_DOWN)
497 		lflags |= GPIO_PULL_DOWN;
498 
499 	if (flags & OF_GPIO_PULL_DISABLE)
500 		lflags |= GPIO_PULL_DISABLE;
501 
502 	return lflags;
503 }
504 
of_find_gpio_rename(struct device_node * np,const char * con_id,unsigned int idx,enum of_gpio_flags * of_flags)505 static struct gpio_desc *of_find_gpio_rename(struct device_node *np,
506 					     const char *con_id,
507 					     unsigned int idx,
508 					     enum of_gpio_flags *of_flags)
509 {
510 	static const struct of_rename_gpio {
511 		const char *con_id;
512 		const char *legacy_id;	/* NULL - same as con_id */
513 		/*
514 		 * Compatible string can be set to NULL in case where
515 		 * matching to a particular compatible is not practical,
516 		 * but it should only be done for gpio names that have
517 		 * vendor prefix to reduce risk of false positives.
518 		 * Addition of such entries is strongly discouraged.
519 		 */
520 		const char *compatible;
521 	} gpios[] = {
522 #if IS_ENABLED(CONFIG_LCD_HX8357)
523 		/* Himax LCD controllers used "gpios-reset" */
524 		{ "reset",	"gpios-reset",	"himax,hx8357" },
525 		{ "reset",	"gpios-reset",	"himax,hx8369" },
526 #endif
527 #if IS_ENABLED(CONFIG_MFD_ARIZONA)
528 		{ "wlf,reset",	NULL,		NULL },
529 #endif
530 #if IS_ENABLED(CONFIG_RTC_DRV_MOXART)
531 		{ "rtc-data",	"gpio-rtc-data",	"moxa,moxart-rtc" },
532 		{ "rtc-sclk",	"gpio-rtc-sclk",	"moxa,moxart-rtc" },
533 		{ "rtc-reset",	"gpio-rtc-reset",	"moxa,moxart-rtc" },
534 #endif
535 #if IS_ENABLED(CONFIG_NFC_MRVL_I2C)
536 		{ "reset",	"reset-n-io",	"marvell,nfc-i2c" },
537 #endif
538 #if IS_ENABLED(CONFIG_NFC_MRVL_SPI)
539 		{ "reset",	"reset-n-io",	"marvell,nfc-spi" },
540 #endif
541 #if IS_ENABLED(CONFIG_NFC_MRVL_UART)
542 		{ "reset",	"reset-n-io",	"marvell,nfc-uart" },
543 		{ "reset",	"reset-n-io",	"mrvl,nfc-uart" },
544 #endif
545 #if IS_ENABLED(CONFIG_PCI_LANTIQ)
546 		/* MIPS Lantiq PCI */
547 		{ "reset",	"gpio-reset",	"lantiq,pci-xway" },
548 #endif
549 
550 		/*
551 		 * Some regulator bindings happened before we managed to
552 		 * establish that GPIO properties should be named
553 		 * "foo-gpios" so we have this special kludge for them.
554 		 */
555 #if IS_ENABLED(CONFIG_REGULATOR_ARIZONA_LDO1)
556 		{ "wlf,ldoena",  NULL,		NULL }, /* Arizona */
557 #endif
558 #if IS_ENABLED(CONFIG_REGULATOR_WM8994)
559 		{ "wlf,ldo1ena", NULL,		NULL }, /* WM8994 */
560 		{ "wlf,ldo2ena", NULL,		NULL }, /* WM8994 */
561 #endif
562 
563 #if IS_ENABLED(CONFIG_SND_SOC_CS42L56)
564 		{ "reset",	"cirrus,gpio-nreset",	"cirrus,cs42l56" },
565 #endif
566 #if IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448)
567 		{ "i2s1-in-sel-gpio1",	NULL,	"mediatek,mt2701-cs42448-machine" },
568 		{ "i2s1-in-sel-gpio2",	NULL,	"mediatek,mt2701-cs42448-machine" },
569 #endif
570 #if IS_ENABLED(CONFIG_SND_SOC_TLV320AIC3X)
571 		{ "reset",	"gpio-reset",	"ti,tlv320aic3x" },
572 		{ "reset",	"gpio-reset",	"ti,tlv320aic33" },
573 		{ "reset",	"gpio-reset",	"ti,tlv320aic3007" },
574 		{ "reset",	"gpio-reset",	"ti,tlv320aic3104" },
575 		{ "reset",	"gpio-reset",	"ti,tlv320aic3106" },
576 #endif
577 #if IS_ENABLED(CONFIG_SPI_GPIO)
578 		/*
579 		 * The SPI GPIO bindings happened before we managed to
580 		 * establish that GPIO properties should be named
581 		 * "foo-gpios" so we have this special kludge for them.
582 		 */
583 		{ "miso",	"gpio-miso",	"spi-gpio" },
584 		{ "mosi",	"gpio-mosi",	"spi-gpio" },
585 		{ "sck",	"gpio-sck",	"spi-gpio" },
586 #endif
587 
588 		/*
589 		 * The old Freescale bindings use simply "gpios" as name
590 		 * for the chip select lines rather than "cs-gpios" like
591 		 * all other SPI hardware. Allow this specifically for
592 		 * Freescale and PPC devices.
593 		 */
594 #if IS_ENABLED(CONFIG_SPI_FSL_SPI)
595 		{ "cs",		"gpios",	"fsl,spi" },
596 		{ "cs",		"gpios",	"aeroflexgaisler,spictrl" },
597 #endif
598 #if IS_ENABLED(CONFIG_SPI_PPC4xx)
599 		{ "cs",		"gpios",	"ibm,ppc4xx-spi" },
600 #endif
601 
602 #if IS_ENABLED(CONFIG_TYPEC_FUSB302)
603 		/*
604 		 * Fairchild FUSB302 host is using undocumented "fcs,int_n"
605 		 * property without the compulsory "-gpios" suffix.
606 		 */
607 		{ "fcs,int_n",	NULL,		"fcs,fusb302" },
608 #endif
609 	};
610 	struct gpio_desc *desc;
611 	const char *legacy_id;
612 	unsigned int i;
613 
614 	if (!con_id)
615 		return ERR_PTR(-ENOENT);
616 
617 	for (i = 0; i < ARRAY_SIZE(gpios); i++) {
618 		if (strcmp(con_id, gpios[i].con_id))
619 			continue;
620 
621 		if (gpios[i].compatible &&
622 		    !of_device_is_compatible(np, gpios[i].compatible))
623 			continue;
624 
625 		legacy_id = gpios[i].legacy_id ?: gpios[i].con_id;
626 		desc = of_get_named_gpiod_flags(np, legacy_id, idx, of_flags);
627 		if (!gpiod_not_found(desc)) {
628 			pr_info("%s uses legacy gpio name '%s' instead of '%s-gpios'\n",
629 				of_node_full_name(np), legacy_id, con_id);
630 			return desc;
631 		}
632 	}
633 
634 	return ERR_PTR(-ENOENT);
635 }
636 
of_find_mt2701_gpio(struct device_node * np,const char * con_id,unsigned int idx,enum of_gpio_flags * of_flags)637 static struct gpio_desc *of_find_mt2701_gpio(struct device_node *np,
638 					     const char *con_id,
639 					     unsigned int idx,
640 					     enum of_gpio_flags *of_flags)
641 {
642 	struct gpio_desc *desc;
643 	const char *legacy_id;
644 
645 	if (!IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448))
646 		return ERR_PTR(-ENOENT);
647 
648 	if (!of_device_is_compatible(np, "mediatek,mt2701-cs42448-machine"))
649 		return ERR_PTR(-ENOENT);
650 
651 	if (!con_id || strcmp(con_id, "i2s1-in-sel"))
652 		return ERR_PTR(-ENOENT);
653 
654 	if (idx == 0)
655 		legacy_id = "i2s1-in-sel-gpio1";
656 	else if (idx == 1)
657 		legacy_id = "i2s1-in-sel-gpio2";
658 	else
659 		return ERR_PTR(-ENOENT);
660 
661 	desc = of_get_named_gpiod_flags(np, legacy_id, 0, of_flags);
662 	if (!gpiod_not_found(desc))
663 		pr_info("%s is using legacy gpio name '%s' instead of '%s-gpios'\n",
664 			of_node_full_name(np), legacy_id, con_id);
665 
666 	return desc;
667 }
668 
669 /*
670  * Trigger sources are special, they allow us to use any GPIO as a LED trigger
671  * and have the name "trigger-sources" no matter which kind of phandle it is
672  * pointing to, whether to a GPIO, a USB host, a network PHY etc. So in this case
673  * we allow looking something up that is not named "foo-gpios".
674  */
of_find_trigger_gpio(struct device_node * np,const char * con_id,unsigned int idx,enum of_gpio_flags * of_flags)675 static struct gpio_desc *of_find_trigger_gpio(struct device_node *np,
676 					      const char *con_id,
677 					      unsigned int idx,
678 					      enum of_gpio_flags *of_flags)
679 {
680 	struct gpio_desc *desc;
681 
682 	if (!IS_ENABLED(CONFIG_LEDS_TRIGGER_GPIO))
683 		return ERR_PTR(-ENOENT);
684 
685 	if (!con_id || strcmp(con_id, "trigger-sources"))
686 		return ERR_PTR(-ENOENT);
687 
688 	desc = of_get_named_gpiod_flags(np, con_id, idx, of_flags);
689 	if (!gpiod_not_found(desc))
690 		pr_debug("%s is used as a trigger\n", of_node_full_name(np));
691 
692 	return desc;
693 }
694 
695 
696 typedef struct gpio_desc *(*of_find_gpio_quirk)(struct device_node *np,
697 						const char *con_id,
698 						unsigned int idx,
699 						enum of_gpio_flags *of_flags);
700 static const of_find_gpio_quirk of_find_gpio_quirks[] = {
701 	of_find_gpio_rename,
702 	of_find_mt2701_gpio,
703 	of_find_trigger_gpio,
704 	NULL
705 };
706 
of_find_gpio(struct device_node * np,const char * con_id,unsigned int idx,unsigned long * flags)707 struct gpio_desc *of_find_gpio(struct device_node *np, const char *con_id,
708 			       unsigned int idx, unsigned long *flags)
709 {
710 	char propname[32]; /* 32 is max size of property name */
711 	enum of_gpio_flags of_flags;
712 	const of_find_gpio_quirk *q;
713 	struct gpio_desc *desc;
714 
715 	/* Try GPIO property "foo-gpios" and "foo-gpio" */
716 	for_each_gpio_property_name(propname, con_id) {
717 		desc = of_get_named_gpiod_flags(np, propname, idx, &of_flags);
718 		if (!gpiod_not_found(desc))
719 			break;
720 	}
721 
722 	/* Properly named GPIO was not found, try workarounds */
723 	for (q = of_find_gpio_quirks; gpiod_not_found(desc) && *q; q++)
724 		desc = (*q)(np, con_id, idx, &of_flags);
725 
726 	if (IS_ERR(desc))
727 		return desc;
728 
729 	*flags = of_convert_gpio_flags(of_flags);
730 
731 	return desc;
732 }
733 
734 /**
735  * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API
736  * @np:		device node to get GPIO from
737  * @chip:	GPIO chip whose hog is parsed
738  * @idx:	Index of the GPIO to parse
739  * @name:	GPIO line name
740  * @lflags:	bitmask of gpio_lookup_flags GPIO_* values - returned from
741  *		of_find_gpio() or of_parse_own_gpio()
742  * @dflags:	gpiod_flags - optional GPIO initialization flags
743  *
744  * Returns:
745  * GPIO descriptor to use with Linux GPIO API, or one of the errno
746  * value on the error condition.
747  */
of_parse_own_gpio(struct device_node * np,struct gpio_chip * chip,unsigned int idx,const char ** name,unsigned long * lflags,enum gpiod_flags * dflags)748 static struct gpio_desc *of_parse_own_gpio(struct device_node *np,
749 					   struct gpio_chip *chip,
750 					   unsigned int idx, const char **name,
751 					   unsigned long *lflags,
752 					   enum gpiod_flags *dflags)
753 {
754 	struct device_node *chip_np;
755 	enum of_gpio_flags xlate_flags;
756 	struct of_phandle_args gpiospec;
757 	struct gpio_desc *desc;
758 	unsigned int i;
759 	u32 tmp;
760 	int ret;
761 
762 	chip_np = dev_of_node(&chip->gpiodev->dev);
763 	if (!chip_np)
764 		return ERR_PTR(-EINVAL);
765 
766 	xlate_flags = 0;
767 	*lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
768 	*dflags = GPIOD_ASIS;
769 
770 	ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp);
771 	if (ret)
772 		return ERR_PTR(ret);
773 
774 	gpiospec.np = chip_np;
775 	gpiospec.args_count = tmp;
776 
777 	for (i = 0; i < tmp; i++) {
778 		ret = of_property_read_u32_index(np, "gpios", idx * tmp + i,
779 						 &gpiospec.args[i]);
780 		if (ret)
781 			return ERR_PTR(ret);
782 	}
783 
784 	desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, &xlate_flags);
785 	if (IS_ERR(desc))
786 		return desc;
787 
788 	*lflags = of_convert_gpio_flags(xlate_flags);
789 
790 	if (of_property_read_bool(np, "input"))
791 		*dflags |= GPIOD_IN;
792 	else if (of_property_read_bool(np, "output-low"))
793 		*dflags |= GPIOD_OUT_LOW;
794 	else if (of_property_read_bool(np, "output-high"))
795 		*dflags |= GPIOD_OUT_HIGH;
796 	else {
797 		pr_warn("GPIO line %d (%pOFn): no hogging state specified, bailing out\n",
798 			desc_to_gpio(desc), np);
799 		return ERR_PTR(-EINVAL);
800 	}
801 
802 	if (name && of_property_read_string(np, "line-name", name))
803 		*name = np->name;
804 
805 	return desc;
806 }
807 
808 /**
809  * of_gpiochip_add_hog - Add all hogs in a hog device node
810  * @chip:	gpio chip to act on
811  * @hog:	device node describing the hogs
812  *
813  * Returns:
814  * 0 on success, or negative errno on failure.
815  */
of_gpiochip_add_hog(struct gpio_chip * chip,struct device_node * hog)816 static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog)
817 {
818 	enum gpiod_flags dflags;
819 	struct gpio_desc *desc;
820 	unsigned long lflags;
821 	const char *name;
822 	unsigned int i;
823 	int ret;
824 
825 	for (i = 0;; i++) {
826 		desc = of_parse_own_gpio(hog, chip, i, &name, &lflags, &dflags);
827 		if (IS_ERR(desc))
828 			break;
829 
830 		ret = gpiod_hog(desc, name, lflags, dflags);
831 		if (ret < 0)
832 			return ret;
833 
834 #ifdef CONFIG_OF_DYNAMIC
835 		WRITE_ONCE(desc->hog, hog);
836 #endif
837 	}
838 
839 	return 0;
840 }
841 
842 /**
843  * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions
844  * @chip:	gpio chip to act on
845  *
846  * This is only used by of_gpiochip_add to request/set GPIO initial
847  * configuration.
848  *
849  * Returns:
850  * 0 on success, or negative errno on failure.
851  */
of_gpiochip_scan_gpios(struct gpio_chip * chip)852 static int of_gpiochip_scan_gpios(struct gpio_chip *chip)
853 {
854 	int ret;
855 
856 	for_each_available_child_of_node_scoped(dev_of_node(&chip->gpiodev->dev), np) {
857 		if (!of_property_read_bool(np, "gpio-hog"))
858 			continue;
859 
860 		ret = of_gpiochip_add_hog(chip, np);
861 		if (ret < 0)
862 			return ret;
863 
864 		of_node_set_flag(np, OF_POPULATED);
865 	}
866 
867 	return 0;
868 }
869 
870 #ifdef CONFIG_OF_DYNAMIC
871 /**
872  * of_gpiochip_remove_hog - Remove all hogs in a hog device node
873  * @chip:	gpio chip to act on
874  * @hog:	device node describing the hogs
875  */
of_gpiochip_remove_hog(struct gpio_chip * chip,struct device_node * hog)876 static void of_gpiochip_remove_hog(struct gpio_chip *chip,
877 				   struct device_node *hog)
878 {
879 	struct gpio_desc *desc;
880 
881 	for_each_gpio_desc_with_flag(chip, desc, FLAG_IS_HOGGED)
882 		if (READ_ONCE(desc->hog) == hog)
883 			gpiochip_free_own_desc(desc);
884 }
885 
of_gpiochip_match_node(struct gpio_chip * chip,const void * data)886 static int of_gpiochip_match_node(struct gpio_chip *chip, const void *data)
887 {
888 	return device_match_of_node(&chip->gpiodev->dev, data);
889 }
890 
of_find_gpio_device_by_node(struct device_node * np)891 static struct gpio_device *of_find_gpio_device_by_node(struct device_node *np)
892 {
893 	return gpio_device_find(np, of_gpiochip_match_node);
894 }
895 
of_gpio_notify(struct notifier_block * nb,unsigned long action,void * arg)896 static int of_gpio_notify(struct notifier_block *nb, unsigned long action,
897 			  void *arg)
898 {
899 	struct gpio_device *gdev __free(gpio_device_put) = NULL;
900 	struct of_reconfig_data *rd = arg;
901 	int ret;
902 
903 	/*
904 	 * This only supports adding and removing complete gpio-hog nodes.
905 	 * Modifying an existing gpio-hog node is not supported (except for
906 	 * changing its "status" property, which is treated the same as
907 	 * addition/removal).
908 	 */
909 	switch (of_reconfig_get_state_change(action, arg)) {
910 	case OF_RECONFIG_CHANGE_ADD:
911 		if (!of_property_read_bool(rd->dn, "gpio-hog"))
912 			return NOTIFY_DONE;	/* not for us */
913 
914 		if (of_node_test_and_set_flag(rd->dn, OF_POPULATED))
915 			return NOTIFY_DONE;
916 
917 		gdev = of_find_gpio_device_by_node(rd->dn->parent);
918 		if (!gdev)
919 			return NOTIFY_DONE;	/* not for us */
920 
921 		ret = of_gpiochip_add_hog(gpio_device_get_chip(gdev), rd->dn);
922 		if (ret < 0) {
923 			pr_err("%s: failed to add hogs for %pOF\n", __func__,
924 			       rd->dn);
925 			of_node_clear_flag(rd->dn, OF_POPULATED);
926 			return notifier_from_errno(ret);
927 		}
928 		return NOTIFY_OK;
929 
930 	case OF_RECONFIG_CHANGE_REMOVE:
931 		if (!of_node_check_flag(rd->dn, OF_POPULATED))
932 			return NOTIFY_DONE;	/* already depopulated */
933 
934 		gdev = of_find_gpio_device_by_node(rd->dn->parent);
935 		if (!gdev)
936 			return NOTIFY_DONE;	/* not for us */
937 
938 		of_gpiochip_remove_hog(gpio_device_get_chip(gdev), rd->dn);
939 		of_node_clear_flag(rd->dn, OF_POPULATED);
940 		return NOTIFY_OK;
941 	}
942 
943 	return NOTIFY_DONE;
944 }
945 
946 struct notifier_block gpio_of_notifier = {
947 	.notifier_call = of_gpio_notify,
948 };
949 #endif /* CONFIG_OF_DYNAMIC */
950 
951 /**
952  * of_gpio_twocell_xlate - translate twocell gpiospec to the GPIO number and flags
953  * @gc:		pointer to the gpio_chip structure
954  * @gpiospec:	GPIO specifier as found in the device tree
955  * @flags:	a flags pointer to fill in
956  *
957  * This is simple translation function, suitable for the most 1:1 mapped
958  * GPIO chips. This function performs only one sanity check: whether GPIO
959  * is less than ngpios (that is specified in the gpio_chip).
960  *
961  * Returns:
962  * GPIO number (>= 0) on success, negative errno on failure.
963  */
of_gpio_twocell_xlate(struct gpio_chip * gc,const struct of_phandle_args * gpiospec,u32 * flags)964 static int of_gpio_twocell_xlate(struct gpio_chip *gc,
965 				 const struct of_phandle_args *gpiospec,
966 				 u32 *flags)
967 {
968 	/*
969 	 * We're discouraging gpio_cells < 2, since that way you'll have to
970 	 * write your own xlate function (that will have to retrieve the GPIO
971 	 * number and the flags from a single gpio cell -- this is possible,
972 	 * but not recommended).
973 	 */
974 	if (gc->of_gpio_n_cells != 2) {
975 		WARN_ON(1);
976 		return -EINVAL;
977 	}
978 
979 	if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
980 		return -EINVAL;
981 
982 	if (gpiospec->args[0] >= gc->ngpio)
983 		return -EINVAL;
984 
985 	if (flags)
986 		*flags = gpiospec->args[1];
987 
988 	return gpiospec->args[0];
989 }
990 
991 /**
992  * of_gpio_threecell_xlate - translate threecell gpiospec to the GPIO number and flags
993  * @gc:		pointer to the gpio_chip structure
994  * @gpiospec:	GPIO specifier as found in the device tree
995  * @flags:	a flags pointer to fill in
996  *
997  * This is simple translation function, suitable for the most 1:n mapped
998  * GPIO chips, i.e. several GPIO chip instances from one device tree node.
999  * In this case the following binding is implied:
1000  *
1001  * foo-gpios = <&gpio instance offset flags>;
1002  *
1003  * Returns:
1004  * GPIO number (>= 0) on success, negative errno on failure.
1005  */
of_gpio_threecell_xlate(struct gpio_chip * gc,const struct of_phandle_args * gpiospec,u32 * flags)1006 static int of_gpio_threecell_xlate(struct gpio_chip *gc,
1007 				   const struct of_phandle_args *gpiospec,
1008 				   u32 *flags)
1009 {
1010 	if (gc->of_gpio_n_cells != 3) {
1011 		WARN_ON(1);
1012 		return -EINVAL;
1013 	}
1014 
1015 	if (WARN_ON(gpiospec->args_count != 3))
1016 		return -EINVAL;
1017 
1018 	/*
1019 	 * Check chip instance number, the driver responds with true if
1020 	 * this is the chip we are looking for.
1021 	 */
1022 	if (!gc->of_node_instance_match(gc, gpiospec->args[0]))
1023 		return -EINVAL;
1024 
1025 	if (gpiospec->args[1] >= gc->ngpio)
1026 		return -EINVAL;
1027 
1028 	if (flags)
1029 		*flags = gpiospec->args[2];
1030 
1031 	return gpiospec->args[1];
1032 }
1033 
1034 #if IS_ENABLED(CONFIG_OF_GPIO_MM_GPIOCHIP)
1035 #include <linux/gpio/legacy-of-mm-gpiochip.h>
1036 /**
1037  * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank)
1038  * @np:		device node of the GPIO chip
1039  * @mm_gc:	pointer to the of_mm_gpio_chip allocated structure
1040  * @data:	driver data to store in the struct gpio_chip
1041  *
1042  * To use this function you should allocate and fill mm_gc with:
1043  *
1044  * 1) In the gpio_chip structure:
1045  *    - all the callbacks
1046  *    - of_gpio_n_cells
1047  *    - of_xlate callback (optional)
1048  *
1049  * 3) In the of_mm_gpio_chip structure:
1050  *    - save_regs callback (optional)
1051  *
1052  * If succeeded, this function will map bank's memory and will
1053  * do all necessary work for you. Then you'll able to use .regs
1054  * to manage GPIOs from the callbacks.
1055  *
1056  * Returns:
1057  * 0 on success, or negative errno on failure.
1058  */
of_mm_gpiochip_add_data(struct device_node * np,struct of_mm_gpio_chip * mm_gc,void * data)1059 int of_mm_gpiochip_add_data(struct device_node *np,
1060 			    struct of_mm_gpio_chip *mm_gc,
1061 			    void *data)
1062 {
1063 	int ret = -ENOMEM;
1064 	struct gpio_chip *gc = &mm_gc->gc;
1065 
1066 	gc->label = kasprintf(GFP_KERNEL, "%pOF", np);
1067 	if (!gc->label)
1068 		goto err0;
1069 
1070 	mm_gc->regs = of_iomap(np, 0);
1071 	if (!mm_gc->regs)
1072 		goto err1;
1073 
1074 	gc->base = -1;
1075 
1076 	if (mm_gc->save_regs)
1077 		mm_gc->save_regs(mm_gc);
1078 
1079 	fwnode_handle_put(mm_gc->gc.fwnode);
1080 	mm_gc->gc.fwnode = fwnode_handle_get(of_fwnode_handle(np));
1081 
1082 	ret = gpiochip_add_data(gc, data);
1083 	if (ret)
1084 		goto err2;
1085 
1086 	return 0;
1087 err2:
1088 	of_node_put(np);
1089 	iounmap(mm_gc->regs);
1090 err1:
1091 	kfree(gc->label);
1092 err0:
1093 	pr_err("%pOF: GPIO chip registration failed with status %d\n", np, ret);
1094 	return ret;
1095 }
1096 EXPORT_SYMBOL_GPL(of_mm_gpiochip_add_data);
1097 
1098 /**
1099  * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank)
1100  * @mm_gc:	pointer to the of_mm_gpio_chip allocated structure
1101  */
of_mm_gpiochip_remove(struct of_mm_gpio_chip * mm_gc)1102 void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc)
1103 {
1104 	struct gpio_chip *gc = &mm_gc->gc;
1105 
1106 	gpiochip_remove(gc);
1107 	iounmap(mm_gc->regs);
1108 	kfree(gc->label);
1109 }
1110 EXPORT_SYMBOL_GPL(of_mm_gpiochip_remove);
1111 #endif
1112 
1113 #ifdef CONFIG_PINCTRL
of_gpiochip_add_pin_range(struct gpio_chip * chip)1114 static int of_gpiochip_add_pin_range(struct gpio_chip *chip)
1115 {
1116 	struct of_phandle_args pinspec;
1117 	struct pinctrl_dev *pctldev;
1118 	struct device_node *np;
1119 	int index = 0, ret, trim;
1120 	const char *name;
1121 	static const char group_names_propname[] = "gpio-ranges-group-names";
1122 	bool has_group_names;
1123 	int offset; /* Offset of the first GPIO line on the chip */
1124 	int pin; /* Pin base number in the range */
1125 	int count; /* Number of pins/GPIO lines to map */
1126 
1127 	np = dev_of_node(&chip->gpiodev->dev);
1128 	if (!np)
1129 		return 0;
1130 
1131 	has_group_names = of_property_present(np, group_names_propname);
1132 
1133 	for (;; index++) {
1134 		/*
1135 		 * Ordinary phandles contain 2-3 cells:
1136 		 * gpios = <&gpio [instance] offset flags>;
1137 		 * Ranges always contain one more cell:
1138 		 * gpio-ranges <&pinctrl [gpio_instance] gpio_offet pin_offet count>;
1139 		 * This is why we parse chip->of_gpio_n_cells + 1 cells
1140 		 */
1141 		ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges",
1142 				chip->of_gpio_n_cells + 1,
1143 				index, &pinspec);
1144 		if (ret)
1145 			break;
1146 
1147 		pctldev = of_pinctrl_get(pinspec.np);
1148 		of_node_put(pinspec.np);
1149 		if (!pctldev)
1150 			return -EPROBE_DEFER;
1151 
1152 		if (chip->of_gpio_n_cells == 3) {
1153 			/* First cell is the gpiochip instance number */
1154 			offset = pinspec.args[1];
1155 			pin = pinspec.args[2];
1156 			count = pinspec.args[3];
1157 		} else {
1158 			offset = pinspec.args[0];
1159 			pin = pinspec.args[1];
1160 			count = pinspec.args[2];
1161 		}
1162 
1163 		/*
1164 		 * With multiple GPIO chips per node, check that this chip is the
1165 		 * right instance.
1166 		 */
1167 		if (chip->of_node_instance_match &&
1168 		    (chip->of_gpio_n_cells == 3) &&
1169 		    !chip->of_node_instance_match(chip, pinspec.args[0]))
1170 			continue;
1171 
1172 		/* Ignore ranges outside of this GPIO chip */
1173 		if (offset >= (chip->offset + chip->ngpio))
1174 			continue;
1175 		if (offset + count <= chip->offset)
1176 			continue;
1177 
1178 		if (count) {
1179 			/* npins != 0: linear range */
1180 			if (has_group_names) {
1181 				of_property_read_string_index(np,
1182 						group_names_propname,
1183 						index, &name);
1184 				if (strlen(name)) {
1185 					pr_err("%pOF: Group name of numeric GPIO ranges must be the empty string.\n",
1186 						np);
1187 					break;
1188 				}
1189 			}
1190 
1191 			/* Trim the range to fit this GPIO chip */
1192 			if (chip->offset > offset) {
1193 				trim = chip->offset - offset;
1194 				count -= trim;
1195 				pin += trim;
1196 				offset = 0;
1197 			} else {
1198 				offset -= chip->offset;
1199 			}
1200 			if ((offset + count) > chip->ngpio)
1201 				count = chip->ngpio - offset;
1202 
1203 			ret = gpiochip_add_pin_range(chip,
1204 					pinctrl_dev_get_devname(pctldev),
1205 					offset,
1206 					pin,
1207 					count);
1208 			if (ret)
1209 				return ret;
1210 		} else {
1211 			/* npins == 0: special range */
1212 			if (pin) {
1213 				pr_err("%pOF: Illegal gpio-range format.\n",
1214 					np);
1215 				break;
1216 			}
1217 
1218 			if (!has_group_names) {
1219 				pr_err("%pOF: GPIO group range requested but no %s property.\n",
1220 					np, group_names_propname);
1221 				break;
1222 			}
1223 
1224 			ret = of_property_read_string_index(np,
1225 						group_names_propname,
1226 						index, &name);
1227 			if (ret)
1228 				break;
1229 
1230 			if (!strlen(name)) {
1231 				pr_err("%pOF: Group name of GPIO group range cannot be the empty string.\n",
1232 				np);
1233 				break;
1234 			}
1235 
1236 			ret = gpiochip_add_pingroup_range(chip, pctldev,
1237 						offset, name);
1238 			if (ret)
1239 				return ret;
1240 		}
1241 	}
1242 
1243 	return 0;
1244 }
1245 
1246 #else
of_gpiochip_add_pin_range(struct gpio_chip * chip)1247 static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; }
1248 #endif
1249 
of_gpiochip_add(struct gpio_chip * chip)1250 int of_gpiochip_add(struct gpio_chip *chip)
1251 {
1252 	struct device_node *np;
1253 	int ret;
1254 
1255 	np = dev_of_node(&chip->gpiodev->dev);
1256 	if (!np)
1257 		return 0;
1258 
1259 	if (!chip->of_xlate) {
1260 		if (chip->of_gpio_n_cells == 3) {
1261 			if (!chip->of_node_instance_match)
1262 				return -EINVAL;
1263 			chip->of_xlate = of_gpio_threecell_xlate;
1264 		} else {
1265 			chip->of_gpio_n_cells = 2;
1266 			chip->of_xlate = of_gpio_twocell_xlate;
1267 		}
1268 	}
1269 
1270 	if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS)
1271 		return -EINVAL;
1272 
1273 	ret = of_gpiochip_add_pin_range(chip);
1274 	if (ret)
1275 		return ret;
1276 
1277 	of_node_get(np);
1278 
1279 	ret = of_gpiochip_scan_gpios(chip);
1280 	if (ret)
1281 		of_node_put(np);
1282 
1283 	return ret;
1284 }
1285 
of_gpiochip_remove(struct gpio_chip * chip)1286 void of_gpiochip_remove(struct gpio_chip *chip)
1287 {
1288 	of_node_put(dev_of_node(&chip->gpiodev->dev));
1289 }
1290 
of_gpiochip_instance_match(struct gpio_chip * gc,unsigned int index)1291 bool of_gpiochip_instance_match(struct gpio_chip *gc, unsigned int index)
1292 {
1293 	if (gc->of_node_instance_match)
1294 		return gc->of_node_instance_match(gc, index);
1295 
1296 	return false;
1297 }
1298