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