xref: /linux/drivers/gpio/gpiolib-of.c (revision f898c16a0624e7f2dcb0b1cda6916c9be6489197)
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 that the empty GPIO specifiers count too. Returns either
50  *   Number of gpios defined in property,
51  *   -EINVAL for an incorrectly formed gpios property, or
52  *   -ENOENT for a missing gpios property
53  *
54  * Example:
55  * gpios = <0
56  *          &gpio1 1 2
57  *          0
58  *          &gpio2 3 4>;
59  *
60  * The above example defines four GPIOs, two of which are not specified.
61  * This function will return '4'
62  */
63 static int of_gpio_named_count(const struct device_node *np,
64 			       const char *propname)
65 {
66 	return of_count_phandle_with_args(np, propname, "#gpio-cells");
67 }
68 
69 /**
70  * of_gpio_spi_cs_get_count() - special GPIO counting for SPI
71  * @np:    Consuming device node
72  * @con_id: Function within the GPIO consumer
73  *
74  * Some elder GPIO controllers need special quirks. Currently we handle
75  * the Freescale and PPC GPIO controller with bindings that doesn't use the
76  * established "cs-gpios" for chip selects but instead rely on
77  * "gpios" for the chip select lines. If we detect this, we redirect
78  * the counting of "cs-gpios" to count "gpios" transparent to the
79  * driver.
80  */
81 static int of_gpio_spi_cs_get_count(const struct device_node *np,
82 				    const char *con_id)
83 {
84 	if (!IS_ENABLED(CONFIG_SPI_MASTER))
85 		return 0;
86 	if (!con_id || strcmp(con_id, "cs"))
87 		return 0;
88 	if (!of_device_is_compatible(np, "fsl,spi") &&
89 	    !of_device_is_compatible(np, "aeroflexgaisler,spictrl") &&
90 	    !of_device_is_compatible(np, "ibm,ppc4xx-spi"))
91 		return 0;
92 	return of_gpio_named_count(np, "gpios");
93 }
94 
95 int of_gpio_count(const struct fwnode_handle *fwnode, const char *con_id)
96 {
97 	const struct device_node *np = to_of_node(fwnode);
98 	int ret;
99 	char propname[32];
100 	unsigned int i;
101 
102 	ret = of_gpio_spi_cs_get_count(np, con_id);
103 	if (ret > 0)
104 		return ret;
105 
106 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
107 		if (con_id)
108 			snprintf(propname, sizeof(propname), "%s-%s",
109 				 con_id, gpio_suffixes[i]);
110 		else
111 			snprintf(propname, sizeof(propname), "%s",
112 				 gpio_suffixes[i]);
113 
114 		ret = of_gpio_named_count(np, propname);
115 		if (ret > 0)
116 			break;
117 	}
118 	return ret ? ret : -ENOENT;
119 }
120 
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 *
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 
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  */
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  */
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 		/*
197 		 * The rb-gpios semantics was undocumented and qi,lb60 (along with
198 		 * the ingenic driver) got it wrong. The active state encodes the
199 		 * NAND ready state, which is high level. Since there's no signal
200 		 * inverter on this board, it should be active-high. Let's fix that
201 		 * here for older DTs so we can re-use the generic nand_gpio_waitrdy()
202 		 * helper, and be consistent with what other drivers do.
203 		 */
204 		{ "qi,lb60",		"rb-gpios",	true },
205 #endif
206 	};
207 	unsigned int i;
208 
209 	for (i = 0; i < ARRAY_SIZE(gpios); i++) {
210 		if (of_device_is_compatible(np, gpios[i].compatible) &&
211 		    !strcmp(propname, gpios[i].propname)) {
212 			of_gpio_quirk_polarity(np, gpios[i].active_high, flags);
213 			break;
214 		}
215 	}
216 }
217 
218 static void of_gpio_set_polarity_by_property(const struct device_node *np,
219 					     const char *propname,
220 					     enum of_gpio_flags *flags)
221 {
222 	const struct device_node *np_compat = np;
223 	const struct device_node *np_propname = np;
224 	static const struct {
225 		const char *compatible;
226 		const char *gpio_propname;
227 		const char *polarity_propname;
228 	} gpios[] = {
229 #if IS_ENABLED(CONFIG_FEC)
230 		/* Freescale Fast Ethernet Controller */
231 		{ "fsl,imx25-fec",   "phy-reset-gpios", "phy-reset-active-high" },
232 		{ "fsl,imx27-fec",   "phy-reset-gpios", "phy-reset-active-high" },
233 		{ "fsl,imx28-fec",   "phy-reset-gpios", "phy-reset-active-high" },
234 		{ "fsl,imx6q-fec",   "phy-reset-gpios", "phy-reset-active-high" },
235 		{ "fsl,mvf600-fec",  "phy-reset-gpios", "phy-reset-active-high" },
236 		{ "fsl,imx6sx-fec",  "phy-reset-gpios", "phy-reset-active-high" },
237 		{ "fsl,imx6ul-fec",  "phy-reset-gpios", "phy-reset-active-high" },
238 		{ "fsl,imx8mq-fec",  "phy-reset-gpios", "phy-reset-active-high" },
239 		{ "fsl,imx8qm-fec",  "phy-reset-gpios", "phy-reset-active-high" },
240 		{ "fsl,s32v234-fec", "phy-reset-gpios", "phy-reset-active-high" },
241 #endif
242 #if IS_ENABLED(CONFIG_PCI_IMX6)
243 		{ "fsl,imx6q-pcie",  "reset-gpio", "reset-gpio-active-high" },
244 		{ "fsl,imx6sx-pcie", "reset-gpio", "reset-gpio-active-high" },
245 		{ "fsl,imx6qp-pcie", "reset-gpio", "reset-gpio-active-high" },
246 		{ "fsl,imx7d-pcie",  "reset-gpio", "reset-gpio-active-high" },
247 		{ "fsl,imx8mq-pcie", "reset-gpio", "reset-gpio-active-high" },
248 		{ "fsl,imx8mm-pcie", "reset-gpio", "reset-gpio-active-high" },
249 		{ "fsl,imx8mp-pcie", "reset-gpio", "reset-gpio-active-high" },
250 #endif
251 
252 		/*
253 		 * The regulator GPIO handles are specified such that the
254 		 * presence or absence of "enable-active-high" solely controls
255 		 * the polarity of the GPIO line. Any phandle flags must
256 		 * be actively ignored.
257 		 */
258 #if IS_ENABLED(CONFIG_REGULATOR_FIXED_VOLTAGE)
259 		{ "regulator-fixed",   "gpios",        "enable-active-high" },
260 		{ "regulator-fixed",   "gpio",         "enable-active-high" },
261 		{ "reg-fixed-voltage", "gpios",        "enable-active-high" },
262 		{ "reg-fixed-voltage", "gpio",         "enable-active-high" },
263 #endif
264 #if IS_ENABLED(CONFIG_REGULATOR_GPIO)
265 		{ "regulator-gpio",    "enable-gpio",  "enable-active-high" },
266 		{ "regulator-gpio",    "enable-gpios", "enable-active-high" },
267 #endif
268 #if IS_ENABLED(CONFIG_MMC_ATMELMCI)
269 		{ "atmel,hsmci",       "cd-gpios",     "cd-inverted" },
270 #endif
271 	};
272 	unsigned int i;
273 	bool active_high;
274 
275 #if IS_ENABLED(CONFIG_MMC_ATMELMCI)
276 	/*
277 	 * The Atmel HSMCI has compatible property in the parent node and
278 	 * gpio property in a child node
279 	 */
280 	if (of_device_is_compatible(np->parent, "atmel,hsmci")) {
281 		np_compat = np->parent;
282 		np_propname = np;
283 	}
284 #endif
285 
286 	for (i = 0; i < ARRAY_SIZE(gpios); i++) {
287 		if (of_device_is_compatible(np_compat, gpios[i].compatible) &&
288 		    !strcmp(propname, gpios[i].gpio_propname)) {
289 			active_high = of_property_read_bool(np_propname,
290 						gpios[i].polarity_propname);
291 			of_gpio_quirk_polarity(np, active_high, flags);
292 			break;
293 		}
294 	}
295 }
296 
297 static void of_gpio_flags_quirks(const struct device_node *np,
298 				 const char *propname,
299 				 enum of_gpio_flags *flags,
300 				 int index)
301 {
302 	of_gpio_try_fixup_polarity(np, propname, flags);
303 	of_gpio_set_polarity_by_property(np, propname, flags);
304 
305 	/*
306 	 * Legacy open drain handling for fixed voltage regulators.
307 	 */
308 	if (IS_ENABLED(CONFIG_REGULATOR) &&
309 	    of_device_is_compatible(np, "reg-fixed-voltage") &&
310 	    of_property_read_bool(np, "gpio-open-drain")) {
311 		*flags |= (OF_GPIO_SINGLE_ENDED | OF_GPIO_OPEN_DRAIN);
312 		pr_info("%s uses legacy open drain flag - update the DTS if you can\n",
313 			of_node_full_name(np));
314 	}
315 
316 	/*
317 	 * Legacy handling of SPI active high chip select. If we have a
318 	 * property named "cs-gpios" we need to inspect the child node
319 	 * to determine if the flags should have inverted semantics.
320 	 */
321 	if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") &&
322 	    of_property_read_bool(np, "cs-gpios")) {
323 		struct device_node *child;
324 		u32 cs;
325 		int ret;
326 
327 		for_each_child_of_node(np, child) {
328 			ret = of_property_read_u32(child, "reg", &cs);
329 			if (ret)
330 				continue;
331 			if (cs == index) {
332 				/*
333 				 * SPI children have active low chip selects
334 				 * by default. This can be specified negatively
335 				 * by just omitting "spi-cs-high" in the
336 				 * device node, or actively by tagging on
337 				 * GPIO_ACTIVE_LOW as flag in the device
338 				 * tree. If the line is simultaneously
339 				 * tagged as active low in the device tree
340 				 * and has the "spi-cs-high" set, we get a
341 				 * conflict and the "spi-cs-high" flag will
342 				 * take precedence.
343 				 */
344 				bool active_high = of_property_read_bool(child,
345 								"spi-cs-high");
346 				of_gpio_quirk_polarity(child, active_high,
347 						       flags);
348 				of_node_put(child);
349 				break;
350 			}
351 		}
352 	}
353 
354 	/* Legacy handling of stmmac's active-low PHY reset line */
355 	if (IS_ENABLED(CONFIG_STMMAC_ETH) &&
356 	    !strcmp(propname, "snps,reset-gpio") &&
357 	    of_property_read_bool(np, "snps,reset-active-low"))
358 		*flags |= OF_GPIO_ACTIVE_LOW;
359 }
360 
361 /**
362  * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API
363  * @np:		device node to get GPIO from
364  * @propname:	property name containing gpio specifier(s)
365  * @index:	index of the GPIO
366  * @flags:	a flags pointer to fill in
367  *
368  * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
369  * value on the error condition. If @flags is not NULL the function also fills
370  * in flags for the GPIO.
371  */
372 static struct gpio_desc *of_get_named_gpiod_flags(const struct device_node *np,
373 		     const char *propname, int index, enum of_gpio_flags *flags)
374 {
375 	struct of_phandle_args gpiospec;
376 	struct gpio_desc *desc;
377 	int ret;
378 
379 	ret = of_parse_phandle_with_args_map(np, propname, "gpio", index,
380 					     &gpiospec);
381 	if (ret) {
382 		pr_debug("%s: can't parse '%s' property of node '%pOF[%d]'\n",
383 			__func__, propname, np, index);
384 		return ERR_PTR(ret);
385 	}
386 
387 	struct gpio_device *gdev __free(gpio_device_put) =
388 				of_find_gpio_device_by_xlate(&gpiospec);
389 	if (!gdev) {
390 		desc = ERR_PTR(-EPROBE_DEFER);
391 		goto out;
392 	}
393 
394 	desc = of_xlate_and_get_gpiod_flags(gpio_device_get_chip(gdev),
395 					    &gpiospec, flags);
396 	if (IS_ERR(desc))
397 		goto out;
398 
399 	if (flags)
400 		of_gpio_flags_quirks(np, propname, flags, index);
401 
402 	pr_debug("%s: parsed '%s' property of node '%pOF[%d]' - status (%d)\n",
403 		 __func__, propname, np, index,
404 		 PTR_ERR_OR_ZERO(desc));
405 
406 out:
407 	of_node_put(gpiospec.np);
408 
409 	return desc;
410 }
411 
412 /**
413  * of_get_named_gpio() - Get a GPIO number to use with GPIO API
414  * @np:		device node to get GPIO from
415  * @propname:	Name of property containing gpio specifier(s)
416  * @index:	index of the GPIO
417  *
418  * **DEPRECATED** This function is deprecated and must not be used in new code.
419  *
420  * Returns GPIO number to use with Linux generic GPIO API, or one of the errno
421  * value on the error condition.
422  */
423 int of_get_named_gpio(const struct device_node *np, const char *propname,
424 		      int index)
425 {
426 	struct gpio_desc *desc;
427 
428 	desc = of_get_named_gpiod_flags(np, propname, index, NULL);
429 
430 	if (IS_ERR(desc))
431 		return PTR_ERR(desc);
432 	else
433 		return desc_to_gpio(desc);
434 }
435 EXPORT_SYMBOL_GPL(of_get_named_gpio);
436 
437 /* Converts gpio_lookup_flags into bitmask of GPIO_* values */
438 static unsigned long of_convert_gpio_flags(enum of_gpio_flags flags)
439 {
440 	unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
441 
442 	if (flags & OF_GPIO_ACTIVE_LOW)
443 		lflags |= GPIO_ACTIVE_LOW;
444 
445 	if (flags & OF_GPIO_SINGLE_ENDED) {
446 		if (flags & OF_GPIO_OPEN_DRAIN)
447 			lflags |= GPIO_OPEN_DRAIN;
448 		else
449 			lflags |= GPIO_OPEN_SOURCE;
450 	}
451 
452 	if (flags & OF_GPIO_TRANSITORY)
453 		lflags |= GPIO_TRANSITORY;
454 
455 	if (flags & OF_GPIO_PULL_UP)
456 		lflags |= GPIO_PULL_UP;
457 
458 	if (flags & OF_GPIO_PULL_DOWN)
459 		lflags |= GPIO_PULL_DOWN;
460 
461 	if (flags & OF_GPIO_PULL_DISABLE)
462 		lflags |= GPIO_PULL_DISABLE;
463 
464 	return lflags;
465 }
466 
467 static struct gpio_desc *of_find_gpio_rename(struct device_node *np,
468 					     const char *con_id,
469 					     unsigned int idx,
470 					     enum of_gpio_flags *of_flags)
471 {
472 	static const struct of_rename_gpio {
473 		const char *con_id;
474 		const char *legacy_id;	/* NULL - same as con_id */
475 		/*
476 		 * Compatible string can be set to NULL in case where
477 		 * matching to a particular compatible is not practical,
478 		 * but it should only be done for gpio names that have
479 		 * vendor prefix to reduce risk of false positives.
480 		 * Addition of such entries is strongly discouraged.
481 		 */
482 		const char *compatible;
483 	} gpios[] = {
484 #if IS_ENABLED(CONFIG_LCD_HX8357)
485 		/* Himax LCD controllers used "gpios-reset" */
486 		{ "reset",	"gpios-reset",	"himax,hx8357" },
487 		{ "reset",	"gpios-reset",	"himax,hx8369" },
488 #endif
489 #if IS_ENABLED(CONFIG_MFD_ARIZONA)
490 		{ "wlf,reset",	NULL,		NULL },
491 #endif
492 #if IS_ENABLED(CONFIG_RTC_DRV_MOXART)
493 		{ "rtc-data",	"gpio-rtc-data",	"moxa,moxart-rtc" },
494 		{ "rtc-sclk",	"gpio-rtc-sclk",	"moxa,moxart-rtc" },
495 		{ "rtc-reset",	"gpio-rtc-reset",	"moxa,moxart-rtc" },
496 #endif
497 #if IS_ENABLED(CONFIG_NFC_MRVL_I2C)
498 		{ "reset",	"reset-n-io",	"marvell,nfc-i2c" },
499 #endif
500 #if IS_ENABLED(CONFIG_NFC_MRVL_SPI)
501 		{ "reset",	"reset-n-io",	"marvell,nfc-spi" },
502 #endif
503 #if IS_ENABLED(CONFIG_NFC_MRVL_UART)
504 		{ "reset",	"reset-n-io",	"marvell,nfc-uart" },
505 		{ "reset",	"reset-n-io",	"mrvl,nfc-uart" },
506 #endif
507 #if !IS_ENABLED(CONFIG_PCI_LANTIQ)
508 		/* MIPS Lantiq PCI */
509 		{ "reset",	"gpios-reset",	"lantiq,pci-xway" },
510 #endif
511 
512 		/*
513 		 * Some regulator bindings happened before we managed to
514 		 * establish that GPIO properties should be named
515 		 * "foo-gpios" so we have this special kludge for them.
516 		 */
517 #if IS_ENABLED(CONFIG_REGULATOR_ARIZONA_LDO1)
518 		{ "wlf,ldoena",  NULL,		NULL }, /* Arizona */
519 #endif
520 #if IS_ENABLED(CONFIG_REGULATOR_WM8994)
521 		{ "wlf,ldo1ena", NULL,		NULL }, /* WM8994 */
522 		{ "wlf,ldo2ena", NULL,		NULL }, /* WM8994 */
523 #endif
524 
525 #if IS_ENABLED(CONFIG_SND_SOC_CS42L56)
526 		{ "reset",	"cirrus,gpio-nreset",	"cirrus,cs42l56" },
527 #endif
528 #if IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448)
529 		{ "i2s1-in-sel-gpio1",	NULL,	"mediatek,mt2701-cs42448-machine" },
530 		{ "i2s1-in-sel-gpio2",	NULL,	"mediatek,mt2701-cs42448-machine" },
531 #endif
532 #if IS_ENABLED(CONFIG_SND_SOC_TLV320AIC3X)
533 		{ "reset",	"gpio-reset",	"ti,tlv320aic3x" },
534 		{ "reset",	"gpio-reset",	"ti,tlv320aic33" },
535 		{ "reset",	"gpio-reset",	"ti,tlv320aic3007" },
536 		{ "reset",	"gpio-reset",	"ti,tlv320aic3104" },
537 		{ "reset",	"gpio-reset",	"ti,tlv320aic3106" },
538 #endif
539 #if IS_ENABLED(CONFIG_SPI_GPIO)
540 		/*
541 		 * The SPI GPIO bindings happened before we managed to
542 		 * establish that GPIO properties should be named
543 		 * "foo-gpios" so we have this special kludge for them.
544 		 */
545 		{ "miso",	"gpio-miso",	"spi-gpio" },
546 		{ "mosi",	"gpio-mosi",	"spi-gpio" },
547 		{ "sck",	"gpio-sck",	"spi-gpio" },
548 #endif
549 
550 		/*
551 		 * The old Freescale bindings use simply "gpios" as name
552 		 * for the chip select lines rather than "cs-gpios" like
553 		 * all other SPI hardware. Allow this specifically for
554 		 * Freescale and PPC devices.
555 		 */
556 #if IS_ENABLED(CONFIG_SPI_FSL_SPI)
557 		{ "cs",		"gpios",	"fsl,spi" },
558 		{ "cs",		"gpios",	"aeroflexgaisler,spictrl" },
559 #endif
560 #if IS_ENABLED(CONFIG_SPI_PPC4xx)
561 		{ "cs",		"gpios",	"ibm,ppc4xx-spi" },
562 #endif
563 
564 #if IS_ENABLED(CONFIG_TYPEC_FUSB302)
565 		/*
566 		 * Fairchild FUSB302 host is using undocumented "fcs,int_n"
567 		 * property without the compulsory "-gpios" suffix.
568 		 */
569 		{ "fcs,int_n",	NULL,		"fcs,fusb302" },
570 #endif
571 	};
572 	struct gpio_desc *desc;
573 	const char *legacy_id;
574 	unsigned int i;
575 
576 	if (!con_id)
577 		return ERR_PTR(-ENOENT);
578 
579 	for (i = 0; i < ARRAY_SIZE(gpios); i++) {
580 		if (strcmp(con_id, gpios[i].con_id))
581 			continue;
582 
583 		if (gpios[i].compatible &&
584 		    !of_device_is_compatible(np, gpios[i].compatible))
585 			continue;
586 
587 		legacy_id = gpios[i].legacy_id ?: gpios[i].con_id;
588 		desc = of_get_named_gpiod_flags(np, legacy_id, idx, of_flags);
589 		if (!gpiod_not_found(desc)) {
590 			pr_info("%s uses legacy gpio name '%s' instead of '%s-gpios'\n",
591 				of_node_full_name(np), legacy_id, con_id);
592 			return desc;
593 		}
594 	}
595 
596 	return ERR_PTR(-ENOENT);
597 }
598 
599 static struct gpio_desc *of_find_mt2701_gpio(struct device_node *np,
600 					     const char *con_id,
601 					     unsigned int idx,
602 					     enum of_gpio_flags *of_flags)
603 {
604 	struct gpio_desc *desc;
605 	const char *legacy_id;
606 
607 	if (!IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448))
608 		return ERR_PTR(-ENOENT);
609 
610 	if (!of_device_is_compatible(np, "mediatek,mt2701-cs42448-machine"))
611 		return ERR_PTR(-ENOENT);
612 
613 	if (!con_id || strcmp(con_id, "i2s1-in-sel"))
614 		return ERR_PTR(-ENOENT);
615 
616 	if (idx == 0)
617 		legacy_id = "i2s1-in-sel-gpio1";
618 	else if (idx == 1)
619 		legacy_id = "i2s1-in-sel-gpio2";
620 	else
621 		return ERR_PTR(-ENOENT);
622 
623 	desc = of_get_named_gpiod_flags(np, legacy_id, 0, of_flags);
624 	if (!gpiod_not_found(desc))
625 		pr_info("%s is using legacy gpio name '%s' instead of '%s-gpios'\n",
626 			of_node_full_name(np), legacy_id, con_id);
627 
628 	return desc;
629 }
630 
631 /*
632  * Trigger sources are special, they allow us to use any GPIO as a LED trigger
633  * and have the name "trigger-sources" no matter which kind of phandle it is
634  * pointing to, whether to a GPIO, a USB host, a network PHY etc. So in this case
635  * we allow looking something up that is not named "foo-gpios".
636  */
637 static struct gpio_desc *of_find_trigger_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 
644 	if (!IS_ENABLED(CONFIG_LEDS_TRIGGER_GPIO))
645 		return ERR_PTR(-ENOENT);
646 
647 	if (!con_id || strcmp(con_id, "trigger-sources"))
648 		return ERR_PTR(-ENOENT);
649 
650 	desc = of_get_named_gpiod_flags(np, con_id, idx, of_flags);
651 	if (!gpiod_not_found(desc))
652 		pr_debug("%s is used as a trigger\n", of_node_full_name(np));
653 
654 	return desc;
655 }
656 
657 
658 typedef struct gpio_desc *(*of_find_gpio_quirk)(struct device_node *np,
659 						const char *con_id,
660 						unsigned int idx,
661 						enum of_gpio_flags *of_flags);
662 static const of_find_gpio_quirk of_find_gpio_quirks[] = {
663 	of_find_gpio_rename,
664 	of_find_mt2701_gpio,
665 	of_find_trigger_gpio,
666 	NULL
667 };
668 
669 struct gpio_desc *of_find_gpio(struct device_node *np, const char *con_id,
670 			       unsigned int idx, unsigned long *flags)
671 {
672 	char prop_name[32]; /* 32 is max size of property name */
673 	enum of_gpio_flags of_flags;
674 	const of_find_gpio_quirk *q;
675 	struct gpio_desc *desc;
676 	unsigned int i;
677 
678 	/* Try GPIO property "foo-gpios" and "foo-gpio" */
679 	for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
680 		if (con_id)
681 			snprintf(prop_name, sizeof(prop_name), "%s-%s", con_id,
682 				 gpio_suffixes[i]);
683 		else
684 			snprintf(prop_name, sizeof(prop_name), "%s",
685 				 gpio_suffixes[i]);
686 
687 		desc = of_get_named_gpiod_flags(np, prop_name, idx, &of_flags);
688 
689 		if (!gpiod_not_found(desc))
690 			break;
691 	}
692 
693 	/* Properly named GPIO was not found, try workarounds */
694 	for (q = of_find_gpio_quirks; gpiod_not_found(desc) && *q; q++)
695 		desc = (*q)(np, con_id, idx, &of_flags);
696 
697 	if (IS_ERR(desc))
698 		return desc;
699 
700 	*flags = of_convert_gpio_flags(of_flags);
701 
702 	return desc;
703 }
704 
705 /**
706  * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API
707  * @np:		device node to get GPIO from
708  * @chip:	GPIO chip whose hog is parsed
709  * @idx:	Index of the GPIO to parse
710  * @name:	GPIO line name
711  * @lflags:	bitmask of gpio_lookup_flags GPIO_* values - returned from
712  *		of_find_gpio() or of_parse_own_gpio()
713  * @dflags:	gpiod_flags - optional GPIO initialization flags
714  *
715  * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
716  * value on the error condition.
717  */
718 static struct gpio_desc *of_parse_own_gpio(struct device_node *np,
719 					   struct gpio_chip *chip,
720 					   unsigned int idx, const char **name,
721 					   unsigned long *lflags,
722 					   enum gpiod_flags *dflags)
723 {
724 	struct device_node *chip_np;
725 	enum of_gpio_flags xlate_flags;
726 	struct of_phandle_args gpiospec;
727 	struct gpio_desc *desc;
728 	unsigned int i;
729 	u32 tmp;
730 	int ret;
731 
732 	chip_np = dev_of_node(&chip->gpiodev->dev);
733 	if (!chip_np)
734 		return ERR_PTR(-EINVAL);
735 
736 	xlate_flags = 0;
737 	*lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
738 	*dflags = GPIOD_ASIS;
739 
740 	ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp);
741 	if (ret)
742 		return ERR_PTR(ret);
743 
744 	gpiospec.np = chip_np;
745 	gpiospec.args_count = tmp;
746 
747 	for (i = 0; i < tmp; i++) {
748 		ret = of_property_read_u32_index(np, "gpios", idx * tmp + i,
749 						 &gpiospec.args[i]);
750 		if (ret)
751 			return ERR_PTR(ret);
752 	}
753 
754 	desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, &xlate_flags);
755 	if (IS_ERR(desc))
756 		return desc;
757 
758 	*lflags = of_convert_gpio_flags(xlate_flags);
759 
760 	if (of_property_read_bool(np, "input"))
761 		*dflags |= GPIOD_IN;
762 	else if (of_property_read_bool(np, "output-low"))
763 		*dflags |= GPIOD_OUT_LOW;
764 	else if (of_property_read_bool(np, "output-high"))
765 		*dflags |= GPIOD_OUT_HIGH;
766 	else {
767 		pr_warn("GPIO line %d (%pOFn): no hogging state specified, bailing out\n",
768 			desc_to_gpio(desc), np);
769 		return ERR_PTR(-EINVAL);
770 	}
771 
772 	if (name && of_property_read_string(np, "line-name", name))
773 		*name = np->name;
774 
775 	return desc;
776 }
777 
778 /**
779  * of_gpiochip_add_hog - Add all hogs in a hog device node
780  * @chip:	gpio chip to act on
781  * @hog:	device node describing the hogs
782  *
783  * Returns error if it fails otherwise 0 on success.
784  */
785 static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog)
786 {
787 	enum gpiod_flags dflags;
788 	struct gpio_desc *desc;
789 	unsigned long lflags;
790 	const char *name;
791 	unsigned int i;
792 	int ret;
793 
794 	for (i = 0;; i++) {
795 		desc = of_parse_own_gpio(hog, chip, i, &name, &lflags, &dflags);
796 		if (IS_ERR(desc))
797 			break;
798 
799 		ret = gpiod_hog(desc, name, lflags, dflags);
800 		if (ret < 0)
801 			return ret;
802 
803 #ifdef CONFIG_OF_DYNAMIC
804 		WRITE_ONCE(desc->hog, hog);
805 #endif
806 	}
807 
808 	return 0;
809 }
810 
811 /**
812  * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions
813  * @chip:	gpio chip to act on
814  *
815  * This is only used by of_gpiochip_add to request/set GPIO initial
816  * configuration.
817  * It returns error if it fails otherwise 0 on success.
818  */
819 static int of_gpiochip_scan_gpios(struct gpio_chip *chip)
820 {
821 	struct device_node *np;
822 	int ret;
823 
824 	for_each_available_child_of_node(dev_of_node(&chip->gpiodev->dev), np) {
825 		if (!of_property_read_bool(np, "gpio-hog"))
826 			continue;
827 
828 		ret = of_gpiochip_add_hog(chip, np);
829 		if (ret < 0) {
830 			of_node_put(np);
831 			return ret;
832 		}
833 
834 		of_node_set_flag(np, OF_POPULATED);
835 	}
836 
837 	return 0;
838 }
839 
840 #ifdef CONFIG_OF_DYNAMIC
841 /**
842  * of_gpiochip_remove_hog - Remove all hogs in a hog device node
843  * @chip:	gpio chip to act on
844  * @hog:	device node describing the hogs
845  */
846 static void of_gpiochip_remove_hog(struct gpio_chip *chip,
847 				   struct device_node *hog)
848 {
849 	struct gpio_desc *desc;
850 
851 	for_each_gpio_desc_with_flag(chip, desc, FLAG_IS_HOGGED)
852 		if (READ_ONCE(desc->hog) == hog)
853 			gpiochip_free_own_desc(desc);
854 }
855 
856 static int of_gpiochip_match_node(struct gpio_chip *chip, const void *data)
857 {
858 	return device_match_of_node(&chip->gpiodev->dev, data);
859 }
860 
861 static struct gpio_device *of_find_gpio_device_by_node(struct device_node *np)
862 {
863 	return gpio_device_find(np, of_gpiochip_match_node);
864 }
865 
866 static int of_gpio_notify(struct notifier_block *nb, unsigned long action,
867 			  void *arg)
868 {
869 	struct gpio_device *gdev __free(gpio_device_put) = NULL;
870 	struct of_reconfig_data *rd = arg;
871 	int ret;
872 
873 	/*
874 	 * This only supports adding and removing complete gpio-hog nodes.
875 	 * Modifying an existing gpio-hog node is not supported (except for
876 	 * changing its "status" property, which is treated the same as
877 	 * addition/removal).
878 	 */
879 	switch (of_reconfig_get_state_change(action, arg)) {
880 	case OF_RECONFIG_CHANGE_ADD:
881 		if (!of_property_read_bool(rd->dn, "gpio-hog"))
882 			return NOTIFY_DONE;	/* not for us */
883 
884 		if (of_node_test_and_set_flag(rd->dn, OF_POPULATED))
885 			return NOTIFY_DONE;
886 
887 		gdev = of_find_gpio_device_by_node(rd->dn->parent);
888 		if (!gdev)
889 			return NOTIFY_DONE;	/* not for us */
890 
891 		ret = of_gpiochip_add_hog(gpio_device_get_chip(gdev), rd->dn);
892 		if (ret < 0) {
893 			pr_err("%s: failed to add hogs for %pOF\n", __func__,
894 			       rd->dn);
895 			of_node_clear_flag(rd->dn, OF_POPULATED);
896 			return notifier_from_errno(ret);
897 		}
898 		return NOTIFY_OK;
899 
900 	case OF_RECONFIG_CHANGE_REMOVE:
901 		if (!of_node_check_flag(rd->dn, OF_POPULATED))
902 			return NOTIFY_DONE;	/* already depopulated */
903 
904 		gdev = of_find_gpio_device_by_node(rd->dn->parent);
905 		if (!gdev)
906 			return NOTIFY_DONE;	/* not for us */
907 
908 		of_gpiochip_remove_hog(gpio_device_get_chip(gdev), rd->dn);
909 		of_node_clear_flag(rd->dn, OF_POPULATED);
910 		return NOTIFY_OK;
911 	}
912 
913 	return NOTIFY_DONE;
914 }
915 
916 struct notifier_block gpio_of_notifier = {
917 	.notifier_call = of_gpio_notify,
918 };
919 #endif /* CONFIG_OF_DYNAMIC */
920 
921 /**
922  * of_gpio_simple_xlate - translate gpiospec to the GPIO number and flags
923  * @gc:		pointer to the gpio_chip structure
924  * @gpiospec:	GPIO specifier as found in the device tree
925  * @flags:	a flags pointer to fill in
926  *
927  * This is simple translation function, suitable for the most 1:1 mapped
928  * GPIO chips. This function performs only one sanity check: whether GPIO
929  * is less than ngpios (that is specified in the gpio_chip).
930  */
931 static int of_gpio_simple_xlate(struct gpio_chip *gc,
932 				const struct of_phandle_args *gpiospec,
933 				u32 *flags)
934 {
935 	/*
936 	 * We're discouraging gpio_cells < 2, since that way you'll have to
937 	 * write your own xlate function (that will have to retrieve the GPIO
938 	 * number and the flags from a single gpio cell -- this is possible,
939 	 * but not recommended).
940 	 */
941 	if (gc->of_gpio_n_cells < 2) {
942 		WARN_ON(1);
943 		return -EINVAL;
944 	}
945 
946 	if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
947 		return -EINVAL;
948 
949 	if (gpiospec->args[0] >= gc->ngpio)
950 		return -EINVAL;
951 
952 	if (flags)
953 		*flags = gpiospec->args[1];
954 
955 	return gpiospec->args[0];
956 }
957 
958 #if IS_ENABLED(CONFIG_OF_GPIO_MM_GPIOCHIP)
959 #include <linux/gpio/legacy-of-mm-gpiochip.h>
960 /**
961  * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank)
962  * @np:		device node of the GPIO chip
963  * @mm_gc:	pointer to the of_mm_gpio_chip allocated structure
964  * @data:	driver data to store in the struct gpio_chip
965  *
966  * To use this function you should allocate and fill mm_gc with:
967  *
968  * 1) In the gpio_chip structure:
969  *    - all the callbacks
970  *    - of_gpio_n_cells
971  *    - of_xlate callback (optional)
972  *
973  * 3) In the of_mm_gpio_chip structure:
974  *    - save_regs callback (optional)
975  *
976  * If succeeded, this function will map bank's memory and will
977  * do all necessary work for you. Then you'll able to use .regs
978  * to manage GPIOs from the callbacks.
979  */
980 int of_mm_gpiochip_add_data(struct device_node *np,
981 			    struct of_mm_gpio_chip *mm_gc,
982 			    void *data)
983 {
984 	int ret = -ENOMEM;
985 	struct gpio_chip *gc = &mm_gc->gc;
986 
987 	gc->label = kasprintf(GFP_KERNEL, "%pOF", np);
988 	if (!gc->label)
989 		goto err0;
990 
991 	mm_gc->regs = of_iomap(np, 0);
992 	if (!mm_gc->regs)
993 		goto err1;
994 
995 	gc->base = -1;
996 
997 	if (mm_gc->save_regs)
998 		mm_gc->save_regs(mm_gc);
999 
1000 	fwnode_handle_put(mm_gc->gc.fwnode);
1001 	mm_gc->gc.fwnode = fwnode_handle_get(of_fwnode_handle(np));
1002 
1003 	ret = gpiochip_add_data(gc, data);
1004 	if (ret)
1005 		goto err2;
1006 
1007 	return 0;
1008 err2:
1009 	of_node_put(np);
1010 	iounmap(mm_gc->regs);
1011 err1:
1012 	kfree(gc->label);
1013 err0:
1014 	pr_err("%pOF: GPIO chip registration failed with status %d\n", np, ret);
1015 	return ret;
1016 }
1017 EXPORT_SYMBOL_GPL(of_mm_gpiochip_add_data);
1018 
1019 /**
1020  * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank)
1021  * @mm_gc:	pointer to the of_mm_gpio_chip allocated structure
1022  */
1023 void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc)
1024 {
1025 	struct gpio_chip *gc = &mm_gc->gc;
1026 
1027 	gpiochip_remove(gc);
1028 	iounmap(mm_gc->regs);
1029 	kfree(gc->label);
1030 }
1031 EXPORT_SYMBOL_GPL(of_mm_gpiochip_remove);
1032 #endif
1033 
1034 #ifdef CONFIG_PINCTRL
1035 static int of_gpiochip_add_pin_range(struct gpio_chip *chip)
1036 {
1037 	struct of_phandle_args pinspec;
1038 	struct pinctrl_dev *pctldev;
1039 	struct device_node *np;
1040 	int index = 0, ret, trim;
1041 	const char *name;
1042 	static const char group_names_propname[] = "gpio-ranges-group-names";
1043 	struct property *group_names;
1044 
1045 	np = dev_of_node(&chip->gpiodev->dev);
1046 	if (!np)
1047 		return 0;
1048 
1049 	group_names = of_find_property(np, group_names_propname, NULL);
1050 
1051 	for (;; index++) {
1052 		ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3,
1053 				index, &pinspec);
1054 		if (ret)
1055 			break;
1056 
1057 		pctldev = of_pinctrl_get(pinspec.np);
1058 		of_node_put(pinspec.np);
1059 		if (!pctldev)
1060 			return -EPROBE_DEFER;
1061 
1062 		/* Ignore ranges outside of this GPIO chip */
1063 		if (pinspec.args[0] >= (chip->offset + chip->ngpio))
1064 			continue;
1065 		if (pinspec.args[0] + pinspec.args[2] <= chip->offset)
1066 			continue;
1067 
1068 		if (pinspec.args[2]) {
1069 			/* npins != 0: linear range */
1070 			if (group_names) {
1071 				of_property_read_string_index(np,
1072 						group_names_propname,
1073 						index, &name);
1074 				if (strlen(name)) {
1075 					pr_err("%pOF: Group name of numeric GPIO ranges must be the empty string.\n",
1076 						np);
1077 					break;
1078 				}
1079 			}
1080 
1081 			/* Trim the range to fit this GPIO chip */
1082 			if (chip->offset > pinspec.args[0]) {
1083 				trim = chip->offset - pinspec.args[0];
1084 				pinspec.args[2] -= trim;
1085 				pinspec.args[1] += trim;
1086 				pinspec.args[0] = 0;
1087 			} else {
1088 				pinspec.args[0] -= chip->offset;
1089 			}
1090 			if ((pinspec.args[0] + pinspec.args[2]) > chip->ngpio)
1091 				pinspec.args[2] = chip->ngpio - pinspec.args[0];
1092 
1093 			ret = gpiochip_add_pin_range(chip,
1094 					pinctrl_dev_get_devname(pctldev),
1095 					pinspec.args[0],
1096 					pinspec.args[1],
1097 					pinspec.args[2]);
1098 			if (ret)
1099 				return ret;
1100 		} else {
1101 			/* npins == 0: special range */
1102 			if (pinspec.args[1]) {
1103 				pr_err("%pOF: Illegal gpio-range format.\n",
1104 					np);
1105 				break;
1106 			}
1107 
1108 			if (!group_names) {
1109 				pr_err("%pOF: GPIO group range requested but no %s property.\n",
1110 					np, group_names_propname);
1111 				break;
1112 			}
1113 
1114 			ret = of_property_read_string_index(np,
1115 						group_names_propname,
1116 						index, &name);
1117 			if (ret)
1118 				break;
1119 
1120 			if (!strlen(name)) {
1121 				pr_err("%pOF: Group name of GPIO group range cannot be the empty string.\n",
1122 				np);
1123 				break;
1124 			}
1125 
1126 			ret = gpiochip_add_pingroup_range(chip, pctldev,
1127 						pinspec.args[0], name);
1128 			if (ret)
1129 				return ret;
1130 		}
1131 	}
1132 
1133 	return 0;
1134 }
1135 
1136 #else
1137 static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; }
1138 #endif
1139 
1140 int of_gpiochip_add(struct gpio_chip *chip)
1141 {
1142 	struct device_node *np;
1143 	int ret;
1144 
1145 	np = dev_of_node(&chip->gpiodev->dev);
1146 	if (!np)
1147 		return 0;
1148 
1149 	if (!chip->of_xlate) {
1150 		chip->of_gpio_n_cells = 2;
1151 		chip->of_xlate = of_gpio_simple_xlate;
1152 	}
1153 
1154 	if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS)
1155 		return -EINVAL;
1156 
1157 	ret = of_gpiochip_add_pin_range(chip);
1158 	if (ret)
1159 		return ret;
1160 
1161 	of_node_get(np);
1162 
1163 	ret = of_gpiochip_scan_gpios(chip);
1164 	if (ret)
1165 		of_node_put(np);
1166 
1167 	return ret;
1168 }
1169 
1170 void of_gpiochip_remove(struct gpio_chip *chip)
1171 {
1172 	of_node_put(dev_of_node(&chip->gpiodev->dev));
1173 }
1174