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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 */
33enum 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 */
63static 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 */
81static 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
95int 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
121static 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
131static struct gpio_device *
132of_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
137static 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 */
157static 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 */
179static 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
218static 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
297static 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 */
372static 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
406out:
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 */
423int 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}
435EXPORT_SYMBOL_GPL(of_get_named_gpio);
436
437/* Converts gpio_lookup_flags into bitmask of GPIO_* values */
438static 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
467static 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
599static 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 */
637static 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
658typedef 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);
662static 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
669struct 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 */
718static 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 */
785static 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 */
819static 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 */
846static 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
856static 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
861static 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
866static 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
916struct 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 */
931static 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 */
980int 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;
1008err2:
1009 of_node_put(np);
1010 iounmap(mm_gc->regs);
1011err1:
1012 kfree(gc->label);
1013err0:
1014 pr_err("%pOF: GPIO chip registration failed with status %d\n", np, ret);
1015 return ret;
1016}
1017EXPORT_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 */
1023void 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}
1031EXPORT_SYMBOL_GPL(of_mm_gpiochip_remove);
1032#endif
1033
1034#ifdef CONFIG_PINCTRL
1035static 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;
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 if (pinspec.args[2]) {
1063 if (group_names) {
1064 of_property_read_string_index(np,
1065 group_names_propname,
1066 index, &name);
1067 if (strlen(name)) {
1068 pr_err("%pOF: Group name of numeric GPIO ranges must be the empty string.\n",
1069 np);
1070 break;
1071 }
1072 }
1073 /* npins != 0: linear range */
1074 ret = gpiochip_add_pin_range(chip,
1075 pinctrl_dev_get_devname(pctldev),
1076 pinspec.args[0],
1077 pinspec.args[1],
1078 pinspec.args[2]);
1079 if (ret)
1080 return ret;
1081 } else {
1082 /* npins == 0: special range */
1083 if (pinspec.args[1]) {
1084 pr_err("%pOF: Illegal gpio-range format.\n",
1085 np);
1086 break;
1087 }
1088
1089 if (!group_names) {
1090 pr_err("%pOF: GPIO group range requested but no %s property.\n",
1091 np, group_names_propname);
1092 break;
1093 }
1094
1095 ret = of_property_read_string_index(np,
1096 group_names_propname,
1097 index, &name);
1098 if (ret)
1099 break;
1100
1101 if (!strlen(name)) {
1102 pr_err("%pOF: Group name of GPIO group range cannot be the empty string.\n",
1103 np);
1104 break;
1105 }
1106
1107 ret = gpiochip_add_pingroup_range(chip, pctldev,
1108 pinspec.args[0], name);
1109 if (ret)
1110 return ret;
1111 }
1112 }
1113
1114 return 0;
1115}
1116
1117#else
1118static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; }
1119#endif
1120
1121int of_gpiochip_add(struct gpio_chip *chip)
1122{
1123 struct device_node *np;
1124 int ret;
1125
1126 np = dev_of_node(&chip->gpiodev->dev);
1127 if (!np)
1128 return 0;
1129
1130 if (!chip->of_xlate) {
1131 chip->of_gpio_n_cells = 2;
1132 chip->of_xlate = of_gpio_simple_xlate;
1133 }
1134
1135 if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS)
1136 return -EINVAL;
1137
1138 ret = of_gpiochip_add_pin_range(chip);
1139 if (ret)
1140 return ret;
1141
1142 of_node_get(np);
1143
1144 ret = of_gpiochip_scan_gpios(chip);
1145 if (ret)
1146 of_node_put(np);
1147
1148 return ret;
1149}
1150
1151void of_gpiochip_remove(struct gpio_chip *chip)
1152{
1153 of_node_put(dev_of_node(&chip->gpiodev->dev));
1154}