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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/module.h>
14#include <linux/io.h>
15#include <linux/gpio/consumer.h>
16#include <linux/of.h>
17#include <linux/of_address.h>
18#include <linux/of_gpio.h>
19#include <linux/pinctrl/pinctrl.h>
20#include <linux/slab.h>
21#include <linux/gpio/machine.h>
22
23#include "gpiolib.h"
24#include "gpiolib-of.h"
25
26/**
27 * of_gpio_spi_cs_get_count() - special GPIO counting for SPI
28 * @dev: Consuming device
29 * @con_id: Function within the GPIO consumer
30 *
31 * Some elder GPIO controllers need special quirks. Currently we handle
32 * the Freescale and PPC GPIO controller with bindings that doesn't use the
33 * established "cs-gpios" for chip selects but instead rely on
34 * "gpios" for the chip select lines. If we detect this, we redirect
35 * the counting of "cs-gpios" to count "gpios" transparent to the
36 * driver.
37 */
38static int of_gpio_spi_cs_get_count(struct device *dev, const char *con_id)
39{
40 struct device_node *np = dev->of_node;
41
42 if (!IS_ENABLED(CONFIG_SPI_MASTER))
43 return 0;
44 if (!con_id || strcmp(con_id, "cs"))
45 return 0;
46 if (!of_device_is_compatible(np, "fsl,spi") &&
47 !of_device_is_compatible(np, "aeroflexgaisler,spictrl") &&
48 !of_device_is_compatible(np, "ibm,ppc4xx-spi"))
49 return 0;
50 return of_gpio_named_count(np, "gpios");
51}
52
53/*
54 * This is used by external users of of_gpio_count() from <linux/of_gpio.h>
55 *
56 * FIXME: get rid of those external users by converting them to GPIO
57 * descriptors and let them all use gpiod_count()
58 */
59int of_gpio_get_count(struct device *dev, const char *con_id)
60{
61 int ret;
62 char propname[32];
63 unsigned int i;
64
65 ret = of_gpio_spi_cs_get_count(dev, con_id);
66 if (ret > 0)
67 return ret;
68
69 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
70 if (con_id)
71 snprintf(propname, sizeof(propname), "%s-%s",
72 con_id, gpio_suffixes[i]);
73 else
74 snprintf(propname, sizeof(propname), "%s",
75 gpio_suffixes[i]);
76
77 ret = of_gpio_named_count(dev->of_node, propname);
78 if (ret > 0)
79 break;
80 }
81 return ret ? ret : -ENOENT;
82}
83
84static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip, void *data)
85{
86 struct of_phandle_args *gpiospec = data;
87
88 return device_match_of_node(&chip->gpiodev->dev, gpiospec->np) &&
89 chip->of_xlate &&
90 chip->of_xlate(chip, gpiospec, NULL) >= 0;
91}
92
93static struct gpio_chip *of_find_gpiochip_by_xlate(
94 struct of_phandle_args *gpiospec)
95{
96 return gpiochip_find(gpiospec, of_gpiochip_match_node_and_xlate);
97}
98
99static struct gpio_desc *of_xlate_and_get_gpiod_flags(struct gpio_chip *chip,
100 struct of_phandle_args *gpiospec,
101 enum of_gpio_flags *flags)
102{
103 int ret;
104
105 if (chip->of_gpio_n_cells != gpiospec->args_count)
106 return ERR_PTR(-EINVAL);
107
108 ret = chip->of_xlate(chip, gpiospec, flags);
109 if (ret < 0)
110 return ERR_PTR(ret);
111
112 return gpiochip_get_desc(chip, ret);
113}
114
115/*
116 * Overrides stated polarity of a gpio line and warns when there is a
117 * discrepancy.
118 */
119static void of_gpio_quirk_polarity(const struct device_node *np,
120 bool active_high,
121 enum of_gpio_flags *flags)
122{
123 if (active_high) {
124 if (*flags & OF_GPIO_ACTIVE_LOW) {
125 pr_warn("%s GPIO handle specifies active low - ignored\n",
126 of_node_full_name(np));
127 *flags &= ~OF_GPIO_ACTIVE_LOW;
128 }
129 } else {
130 if (!(*flags & OF_GPIO_ACTIVE_LOW))
131 pr_info("%s enforce active low on GPIO handle\n",
132 of_node_full_name(np));
133 *flags |= OF_GPIO_ACTIVE_LOW;
134 }
135}
136
137/*
138 * This quirk does static polarity overrides in cases where existing
139 * DTS specified incorrect polarity.
140 */
141static void of_gpio_try_fixup_polarity(const struct device_node *np,
142 const char *propname,
143 enum of_gpio_flags *flags)
144{
145 static const struct {
146 const char *compatible;
147 const char *propname;
148 bool active_high;
149 } gpios[] = {
150#if !IS_ENABLED(CONFIG_LCD_HX8357)
151 /*
152 * Himax LCD controllers used incorrectly named
153 * "gpios-reset" property and also specified wrong
154 * polarity.
155 */
156 { "himax,hx8357", "gpios-reset", false },
157 { "himax,hx8369", "gpios-reset", false },
158#endif
159 };
160 unsigned int i;
161
162 for (i = 0; i < ARRAY_SIZE(gpios); i++) {
163 if (of_device_is_compatible(np, gpios[i].compatible) &&
164 !strcmp(propname, gpios[i].propname)) {
165 of_gpio_quirk_polarity(np, gpios[i].active_high, flags);
166 break;
167 }
168 }
169}
170
171static void of_gpio_set_polarity_by_property(const struct device_node *np,
172 const char *propname,
173 enum of_gpio_flags *flags)
174{
175 static const struct {
176 const char *compatible;
177 const char *gpio_propname;
178 const char *polarity_propname;
179 } gpios[] = {
180#if IS_ENABLED(CONFIG_FEC)
181 /* Freescale Fast Ethernet Controller */
182 { "fsl,imx25-fec", "phy-reset-gpios", "phy-reset-active-high" },
183 { "fsl,imx27-fec", "phy-reset-gpios", "phy-reset-active-high" },
184 { "fsl,imx28-fec", "phy-reset-gpios", "phy-reset-active-high" },
185 { "fsl,imx6q-fec", "phy-reset-gpios", "phy-reset-active-high" },
186 { "fsl,mvf600-fec", "phy-reset-gpios", "phy-reset-active-high" },
187 { "fsl,imx6sx-fec", "phy-reset-gpios", "phy-reset-active-high" },
188 { "fsl,imx6ul-fec", "phy-reset-gpios", "phy-reset-active-high" },
189 { "fsl,imx8mq-fec", "phy-reset-gpios", "phy-reset-active-high" },
190 { "fsl,imx8qm-fec", "phy-reset-gpios", "phy-reset-active-high" },
191 { "fsl,s32v234-fec", "phy-reset-gpios", "phy-reset-active-high" },
192#endif
193#if IS_ENABLED(CONFIG_PCI_IMX6)
194 { "fsl,imx6q-pcie", "reset-gpio", "reset-gpio-active-high" },
195 { "fsl,imx6sx-pcie", "reset-gpio", "reset-gpio-active-high" },
196 { "fsl,imx6qp-pcie", "reset-gpio", "reset-gpio-active-high" },
197 { "fsl,imx7d-pcie", "reset-gpio", "reset-gpio-active-high" },
198 { "fsl,imx8mq-pcie", "reset-gpio", "reset-gpio-active-high" },
199 { "fsl,imx8mm-pcie", "reset-gpio", "reset-gpio-active-high" },
200 { "fsl,imx8mp-pcie", "reset-gpio", "reset-gpio-active-high" },
201#endif
202
203 /*
204 * The regulator GPIO handles are specified such that the
205 * presence or absence of "enable-active-high" solely controls
206 * the polarity of the GPIO line. Any phandle flags must
207 * be actively ignored.
208 */
209#if IS_ENABLED(CONFIG_REGULATOR_FIXED_VOLTAGE)
210 { "regulator-fixed", "gpios", "enable-active-high" },
211 { "regulator-fixed", "gpio", "enable-active-high" },
212 { "reg-fixed-voltage", "gpios", "enable-active-high" },
213 { "reg-fixed-voltage", "gpio", "enable-active-high" },
214#endif
215#if IS_ENABLED(CONFIG_REGULATOR_GPIO)
216 { "regulator-gpio", "enable-gpio", "enable-active-high" },
217 { "regulator-gpio", "enable-gpios", "enable-active-high" },
218#endif
219 };
220 unsigned int i;
221 bool active_high;
222
223 for (i = 0; i < ARRAY_SIZE(gpios); i++) {
224 if (of_device_is_compatible(np, gpios[i].compatible) &&
225 !strcmp(propname, gpios[i].gpio_propname)) {
226 active_high = of_property_read_bool(np,
227 gpios[i].polarity_propname);
228 of_gpio_quirk_polarity(np, active_high, flags);
229 break;
230 }
231 }
232}
233
234static void of_gpio_flags_quirks(const struct device_node *np,
235 const char *propname,
236 enum of_gpio_flags *flags,
237 int index)
238{
239 of_gpio_try_fixup_polarity(np, propname, flags);
240 of_gpio_set_polarity_by_property(np, propname, flags);
241
242 /*
243 * Legacy open drain handling for fixed voltage regulators.
244 */
245 if (IS_ENABLED(CONFIG_REGULATOR) &&
246 of_device_is_compatible(np, "reg-fixed-voltage") &&
247 of_property_read_bool(np, "gpio-open-drain")) {
248 *flags |= (OF_GPIO_SINGLE_ENDED | OF_GPIO_OPEN_DRAIN);
249 pr_info("%s uses legacy open drain flag - update the DTS if you can\n",
250 of_node_full_name(np));
251 }
252
253 /*
254 * Legacy handling of SPI active high chip select. If we have a
255 * property named "cs-gpios" we need to inspect the child node
256 * to determine if the flags should have inverted semantics.
257 */
258 if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") &&
259 of_property_read_bool(np, "cs-gpios")) {
260 struct device_node *child;
261 u32 cs;
262 int ret;
263
264 for_each_child_of_node(np, child) {
265 ret = of_property_read_u32(child, "reg", &cs);
266 if (ret)
267 continue;
268 if (cs == index) {
269 /*
270 * SPI children have active low chip selects
271 * by default. This can be specified negatively
272 * by just omitting "spi-cs-high" in the
273 * device node, or actively by tagging on
274 * GPIO_ACTIVE_LOW as flag in the device
275 * tree. If the line is simultaneously
276 * tagged as active low in the device tree
277 * and has the "spi-cs-high" set, we get a
278 * conflict and the "spi-cs-high" flag will
279 * take precedence.
280 */
281 bool active_high = of_property_read_bool(child,
282 "spi-cs-high");
283 of_gpio_quirk_polarity(child, active_high,
284 flags);
285 of_node_put(child);
286 break;
287 }
288 }
289 }
290
291 /* Legacy handling of stmmac's active-low PHY reset line */
292 if (IS_ENABLED(CONFIG_STMMAC_ETH) &&
293 !strcmp(propname, "snps,reset-gpio") &&
294 of_property_read_bool(np, "snps,reset-active-low"))
295 *flags |= OF_GPIO_ACTIVE_LOW;
296}
297
298/**
299 * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API
300 * @np: device node to get GPIO from
301 * @propname: property name containing gpio specifier(s)
302 * @index: index of the GPIO
303 * @flags: a flags pointer to fill in
304 *
305 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
306 * value on the error condition. If @flags is not NULL the function also fills
307 * in flags for the GPIO.
308 */
309static struct gpio_desc *of_get_named_gpiod_flags(const struct device_node *np,
310 const char *propname, int index, enum of_gpio_flags *flags)
311{
312 struct of_phandle_args gpiospec;
313 struct gpio_chip *chip;
314 struct gpio_desc *desc;
315 int ret;
316
317 ret = of_parse_phandle_with_args_map(np, propname, "gpio", index,
318 &gpiospec);
319 if (ret) {
320 pr_debug("%s: can't parse '%s' property of node '%pOF[%d]'\n",
321 __func__, propname, np, index);
322 return ERR_PTR(ret);
323 }
324
325 chip = of_find_gpiochip_by_xlate(&gpiospec);
326 if (!chip) {
327 desc = ERR_PTR(-EPROBE_DEFER);
328 goto out;
329 }
330
331 desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, flags);
332 if (IS_ERR(desc))
333 goto out;
334
335 if (flags)
336 of_gpio_flags_quirks(np, propname, flags, index);
337
338 pr_debug("%s: parsed '%s' property of node '%pOF[%d]' - status (%d)\n",
339 __func__, propname, np, index,
340 PTR_ERR_OR_ZERO(desc));
341
342out:
343 of_node_put(gpiospec.np);
344
345 return desc;
346}
347
348int of_get_named_gpio_flags(const struct device_node *np, const char *list_name,
349 int index, enum of_gpio_flags *flags)
350{
351 struct gpio_desc *desc;
352
353 desc = of_get_named_gpiod_flags(np, list_name, index, flags);
354
355 if (IS_ERR(desc))
356 return PTR_ERR(desc);
357 else
358 return desc_to_gpio(desc);
359}
360EXPORT_SYMBOL_GPL(of_get_named_gpio_flags);
361
362/* Converts gpio_lookup_flags into bitmask of GPIO_* values */
363static unsigned long of_convert_gpio_flags(enum of_gpio_flags flags)
364{
365 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
366
367 if (flags & OF_GPIO_ACTIVE_LOW)
368 lflags |= GPIO_ACTIVE_LOW;
369
370 if (flags & OF_GPIO_SINGLE_ENDED) {
371 if (flags & OF_GPIO_OPEN_DRAIN)
372 lflags |= GPIO_OPEN_DRAIN;
373 else
374 lflags |= GPIO_OPEN_SOURCE;
375 }
376
377 if (flags & OF_GPIO_TRANSITORY)
378 lflags |= GPIO_TRANSITORY;
379
380 if (flags & OF_GPIO_PULL_UP)
381 lflags |= GPIO_PULL_UP;
382
383 if (flags & OF_GPIO_PULL_DOWN)
384 lflags |= GPIO_PULL_DOWN;
385
386 if (flags & OF_GPIO_PULL_DISABLE)
387 lflags |= GPIO_PULL_DISABLE;
388
389 return lflags;
390}
391
392/**
393 * gpiod_get_from_of_node() - obtain a GPIO from an OF node
394 * @node: handle of the OF node
395 * @propname: name of the DT property representing the GPIO
396 * @index: index of the GPIO to obtain for the consumer
397 * @dflags: GPIO initialization flags
398 * @label: label to attach to the requested GPIO
399 *
400 * Returns:
401 * On successful request the GPIO pin is configured in accordance with
402 * provided @dflags.
403 *
404 * In case of error an ERR_PTR() is returned.
405 */
406struct gpio_desc *gpiod_get_from_of_node(const struct device_node *node,
407 const char *propname, int index,
408 enum gpiod_flags dflags,
409 const char *label)
410{
411 unsigned long lflags;
412 struct gpio_desc *desc;
413 enum of_gpio_flags of_flags;
414 int ret;
415
416 desc = of_get_named_gpiod_flags(node, propname, index, &of_flags);
417 if (!desc || IS_ERR(desc))
418 return desc;
419
420 ret = gpiod_request(desc, label);
421 if (ret == -EBUSY && (dflags & GPIOD_FLAGS_BIT_NONEXCLUSIVE))
422 return desc;
423 if (ret)
424 return ERR_PTR(ret);
425
426 lflags = of_convert_gpio_flags(of_flags);
427
428 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
429 if (ret < 0) {
430 gpiod_put(desc);
431 return ERR_PTR(ret);
432 }
433
434 return desc;
435}
436EXPORT_SYMBOL_GPL(gpiod_get_from_of_node);
437
438static struct gpio_desc *of_find_gpio_rename(struct device_node *np,
439 const char *con_id,
440 unsigned int idx,
441 enum of_gpio_flags *of_flags)
442{
443 static const struct of_rename_gpio {
444 const char *con_id;
445 const char *legacy_id; /* NULL - same as con_id */
446 /*
447 * Compatible string can be set to NULL in case where
448 * matching to a particular compatible is not practical,
449 * but it should only be done for gpio names that have
450 * vendor prefix to reduce risk of false positives.
451 * Addition of such entries is strongly discouraged.
452 */
453 const char *compatible;
454 } gpios[] = {
455#if !IS_ENABLED(CONFIG_LCD_HX8357)
456 /* Himax LCD controllers used "gpios-reset" */
457 { "reset", "gpios-reset", "himax,hx8357" },
458 { "reset", "gpios-reset", "himax,hx8369" },
459#endif
460#if IS_ENABLED(CONFIG_MFD_ARIZONA)
461 { "wlf,reset", NULL, NULL },
462#endif
463#if IS_ENABLED(CONFIG_RTC_DRV_MOXART)
464 { "rtc-data", "gpio-rtc-data", "moxa,moxart-rtc" },
465 { "rtc-sclk", "gpio-rtc-sclk", "moxa,moxart-rtc" },
466 { "rtc-reset", "gpio-rtc-reset", "moxa,moxart-rtc" },
467#endif
468#if IS_ENABLED(CONFIG_NFC_MRVL_I2C)
469 { "reset", "reset-n-io", "marvell,nfc-i2c" },
470#endif
471#if IS_ENABLED(CONFIG_NFC_MRVL_SPI)
472 { "reset", "reset-n-io", "marvell,nfc-spi" },
473#endif
474#if IS_ENABLED(CONFIG_NFC_MRVL_UART)
475 { "reset", "reset-n-io", "marvell,nfc-uart" },
476 { "reset", "reset-n-io", "mrvl,nfc-uart" },
477#endif
478#if !IS_ENABLED(CONFIG_PCI_LANTIQ)
479 /* MIPS Lantiq PCI */
480 { "reset", "gpios-reset", "lantiq,pci-xway" },
481#endif
482
483 /*
484 * Some regulator bindings happened before we managed to
485 * establish that GPIO properties should be named
486 * "foo-gpios" so we have this special kludge for them.
487 */
488#if IS_ENABLED(CONFIG_REGULATOR_ARIZONA_LDO1)
489 { "wlf,ldoena", NULL, NULL }, /* Arizona */
490#endif
491#if IS_ENABLED(CONFIG_REGULATOR_WM8994)
492 { "wlf,ldo1ena", NULL, NULL }, /* WM8994 */
493 { "wlf,ldo2ena", NULL, NULL }, /* WM8994 */
494#endif
495
496#if IS_ENABLED(CONFIG_SND_SOC_CS42L56)
497 { "reset", "cirrus,gpio-nreset", "cirrus,cs42l56" },
498#endif
499#if IS_ENABLED(CONFIG_SND_SOC_TLV320AIC3X)
500 { "reset", "gpio-reset", "ti,tlv320aic3x" },
501 { "reset", "gpio-reset", "ti,tlv320aic33" },
502 { "reset", "gpio-reset", "ti,tlv320aic3007" },
503 { "reset", "gpio-reset", "ti,tlv320aic3104" },
504 { "reset", "gpio-reset", "ti,tlv320aic3106" },
505#endif
506#if IS_ENABLED(CONFIG_SPI_GPIO)
507 /*
508 * The SPI GPIO bindings happened before we managed to
509 * establish that GPIO properties should be named
510 * "foo-gpios" so we have this special kludge for them.
511 */
512 { "miso", "gpio-miso", "spi-gpio" },
513 { "mosi", "gpio-mosi", "spi-gpio" },
514 { "sck", "gpio-sck", "spi-gpio" },
515#endif
516
517 /*
518 * The old Freescale bindings use simply "gpios" as name
519 * for the chip select lines rather than "cs-gpios" like
520 * all other SPI hardware. Allow this specifically for
521 * Freescale and PPC devices.
522 */
523#if IS_ENABLED(CONFIG_SPI_FSL_SPI)
524 { "cs", "gpios", "fsl,spi" },
525 { "cs", "gpios", "aeroflexgaisler,spictrl" },
526#endif
527#if IS_ENABLED(CONFIG_SPI_PPC4xx)
528 { "cs", "gpios", "ibm,ppc4xx-spi" },
529#endif
530
531#if IS_ENABLED(CONFIG_TYPEC_FUSB302)
532 /*
533 * Fairchild FUSB302 host is using undocumented "fcs,int_n"
534 * property without the compulsory "-gpios" suffix.
535 */
536 { "fcs,int_n", NULL, "fcs,fusb302" },
537#endif
538 };
539 struct gpio_desc *desc;
540 const char *legacy_id;
541 unsigned int i;
542
543 if (!con_id)
544 return ERR_PTR(-ENOENT);
545
546 for (i = 0; i < ARRAY_SIZE(gpios); i++) {
547 if (strcmp(con_id, gpios[i].con_id))
548 continue;
549
550 if (gpios[i].compatible &&
551 !of_device_is_compatible(np, gpios[i].compatible))
552 continue;
553
554 legacy_id = gpios[i].legacy_id ?: gpios[i].con_id;
555 desc = of_get_named_gpiod_flags(np, legacy_id, idx, of_flags);
556 if (!gpiod_not_found(desc)) {
557 pr_info("%s uses legacy gpio name '%s' instead of '%s-gpios'\n",
558 of_node_full_name(np), legacy_id, con_id);
559 return desc;
560 }
561 }
562
563 return ERR_PTR(-ENOENT);
564}
565
566static struct gpio_desc *of_find_mt2701_gpio(struct device_node *np,
567 const char *con_id,
568 unsigned int idx,
569 enum of_gpio_flags *of_flags)
570{
571 struct gpio_desc *desc;
572 const char *legacy_id;
573
574 if (!IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448))
575 return ERR_PTR(-ENOENT);
576
577 if (!of_device_is_compatible(np, "mediatek,mt2701-cs42448-machine"))
578 return ERR_PTR(-ENOENT);
579
580 if (!con_id || strcmp(con_id, "i2s1-in-sel"))
581 return ERR_PTR(-ENOENT);
582
583 if (idx == 0)
584 legacy_id = "i2s1-in-sel-gpio1";
585 else if (idx == 1)
586 legacy_id = "i2s1-in-sel-gpio2";
587 else
588 return ERR_PTR(-ENOENT);
589
590 desc = of_get_named_gpiod_flags(np, legacy_id, 0, of_flags);
591 if (!gpiod_not_found(desc))
592 pr_info("%s is using legacy gpio name '%s' instead of '%s-gpios'\n",
593 of_node_full_name(np), legacy_id, con_id);
594
595 return desc;
596}
597
598typedef struct gpio_desc *(*of_find_gpio_quirk)(struct device_node *np,
599 const char *con_id,
600 unsigned int idx,
601 enum of_gpio_flags *of_flags);
602static const of_find_gpio_quirk of_find_gpio_quirks[] = {
603 of_find_gpio_rename,
604 of_find_mt2701_gpio,
605 NULL
606};
607
608struct gpio_desc *of_find_gpio(struct device_node *np, const char *con_id,
609 unsigned int idx, unsigned long *flags)
610{
611 char prop_name[32]; /* 32 is max size of property name */
612 enum of_gpio_flags of_flags;
613 const of_find_gpio_quirk *q;
614 struct gpio_desc *desc;
615 unsigned int i;
616
617 /* Try GPIO property "foo-gpios" and "foo-gpio" */
618 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
619 if (con_id)
620 snprintf(prop_name, sizeof(prop_name), "%s-%s", con_id,
621 gpio_suffixes[i]);
622 else
623 snprintf(prop_name, sizeof(prop_name), "%s",
624 gpio_suffixes[i]);
625
626 desc = of_get_named_gpiod_flags(np, prop_name, idx, &of_flags);
627
628 if (!gpiod_not_found(desc))
629 break;
630 }
631
632 /* Properly named GPIO was not found, try workarounds */
633 for (q = of_find_gpio_quirks; gpiod_not_found(desc) && *q; q++)
634 desc = (*q)(np, con_id, idx, &of_flags);
635
636 if (IS_ERR(desc))
637 return desc;
638
639 *flags = of_convert_gpio_flags(of_flags);
640
641 return desc;
642}
643
644/**
645 * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API
646 * @np: device node to get GPIO from
647 * @chip: GPIO chip whose hog is parsed
648 * @idx: Index of the GPIO to parse
649 * @name: GPIO line name
650 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
651 * of_find_gpio() or of_parse_own_gpio()
652 * @dflags: gpiod_flags - optional GPIO initialization flags
653 *
654 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
655 * value on the error condition.
656 */
657static struct gpio_desc *of_parse_own_gpio(struct device_node *np,
658 struct gpio_chip *chip,
659 unsigned int idx, const char **name,
660 unsigned long *lflags,
661 enum gpiod_flags *dflags)
662{
663 struct device_node *chip_np;
664 enum of_gpio_flags xlate_flags;
665 struct of_phandle_args gpiospec;
666 struct gpio_desc *desc;
667 unsigned int i;
668 u32 tmp;
669 int ret;
670
671 chip_np = chip->of_node;
672 if (!chip_np)
673 return ERR_PTR(-EINVAL);
674
675 xlate_flags = 0;
676 *lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
677 *dflags = GPIOD_ASIS;
678
679 ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp);
680 if (ret)
681 return ERR_PTR(ret);
682
683 gpiospec.np = chip_np;
684 gpiospec.args_count = tmp;
685
686 for (i = 0; i < tmp; i++) {
687 ret = of_property_read_u32_index(np, "gpios", idx * tmp + i,
688 &gpiospec.args[i]);
689 if (ret)
690 return ERR_PTR(ret);
691 }
692
693 desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, &xlate_flags);
694 if (IS_ERR(desc))
695 return desc;
696
697 *lflags = of_convert_gpio_flags(xlate_flags);
698
699 if (of_property_read_bool(np, "input"))
700 *dflags |= GPIOD_IN;
701 else if (of_property_read_bool(np, "output-low"))
702 *dflags |= GPIOD_OUT_LOW;
703 else if (of_property_read_bool(np, "output-high"))
704 *dflags |= GPIOD_OUT_HIGH;
705 else {
706 pr_warn("GPIO line %d (%pOFn): no hogging state specified, bailing out\n",
707 desc_to_gpio(desc), np);
708 return ERR_PTR(-EINVAL);
709 }
710
711 if (name && of_property_read_string(np, "line-name", name))
712 *name = np->name;
713
714 return desc;
715}
716
717/**
718 * of_gpiochip_add_hog - Add all hogs in a hog device node
719 * @chip: gpio chip to act on
720 * @hog: device node describing the hogs
721 *
722 * Returns error if it fails otherwise 0 on success.
723 */
724static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog)
725{
726 enum gpiod_flags dflags;
727 struct gpio_desc *desc;
728 unsigned long lflags;
729 const char *name;
730 unsigned int i;
731 int ret;
732
733 for (i = 0;; i++) {
734 desc = of_parse_own_gpio(hog, chip, i, &name, &lflags, &dflags);
735 if (IS_ERR(desc))
736 break;
737
738 ret = gpiod_hog(desc, name, lflags, dflags);
739 if (ret < 0)
740 return ret;
741
742#ifdef CONFIG_OF_DYNAMIC
743 desc->hog = hog;
744#endif
745 }
746
747 return 0;
748}
749
750/**
751 * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions
752 * @chip: gpio chip to act on
753 *
754 * This is only used by of_gpiochip_add to request/set GPIO initial
755 * configuration.
756 * It returns error if it fails otherwise 0 on success.
757 */
758static int of_gpiochip_scan_gpios(struct gpio_chip *chip)
759{
760 struct device_node *np;
761 int ret;
762
763 for_each_available_child_of_node(chip->of_node, np) {
764 if (!of_property_read_bool(np, "gpio-hog"))
765 continue;
766
767 ret = of_gpiochip_add_hog(chip, np);
768 if (ret < 0) {
769 of_node_put(np);
770 return ret;
771 }
772
773 of_node_set_flag(np, OF_POPULATED);
774 }
775
776 return 0;
777}
778
779#ifdef CONFIG_OF_DYNAMIC
780/**
781 * of_gpiochip_remove_hog - Remove all hogs in a hog device node
782 * @chip: gpio chip to act on
783 * @hog: device node describing the hogs
784 */
785static void of_gpiochip_remove_hog(struct gpio_chip *chip,
786 struct device_node *hog)
787{
788 struct gpio_desc *desc;
789
790 for_each_gpio_desc_with_flag(chip, desc, FLAG_IS_HOGGED)
791 if (desc->hog == hog)
792 gpiochip_free_own_desc(desc);
793}
794
795static int of_gpiochip_match_node(struct gpio_chip *chip, void *data)
796{
797 return device_match_of_node(&chip->gpiodev->dev, data);
798}
799
800static struct gpio_chip *of_find_gpiochip_by_node(struct device_node *np)
801{
802 return gpiochip_find(np, of_gpiochip_match_node);
803}
804
805static int of_gpio_notify(struct notifier_block *nb, unsigned long action,
806 void *arg)
807{
808 struct of_reconfig_data *rd = arg;
809 struct gpio_chip *chip;
810 int ret;
811
812 /*
813 * This only supports adding and removing complete gpio-hog nodes.
814 * Modifying an existing gpio-hog node is not supported (except for
815 * changing its "status" property, which is treated the same as
816 * addition/removal).
817 */
818 switch (of_reconfig_get_state_change(action, arg)) {
819 case OF_RECONFIG_CHANGE_ADD:
820 if (!of_property_read_bool(rd->dn, "gpio-hog"))
821 return NOTIFY_OK; /* not for us */
822
823 if (of_node_test_and_set_flag(rd->dn, OF_POPULATED))
824 return NOTIFY_OK;
825
826 chip = of_find_gpiochip_by_node(rd->dn->parent);
827 if (chip == NULL)
828 return NOTIFY_OK; /* not for us */
829
830 ret = of_gpiochip_add_hog(chip, rd->dn);
831 if (ret < 0) {
832 pr_err("%s: failed to add hogs for %pOF\n", __func__,
833 rd->dn);
834 of_node_clear_flag(rd->dn, OF_POPULATED);
835 return notifier_from_errno(ret);
836 }
837 break;
838
839 case OF_RECONFIG_CHANGE_REMOVE:
840 if (!of_node_check_flag(rd->dn, OF_POPULATED))
841 return NOTIFY_OK; /* already depopulated */
842
843 chip = of_find_gpiochip_by_node(rd->dn->parent);
844 if (chip == NULL)
845 return NOTIFY_OK; /* not for us */
846
847 of_gpiochip_remove_hog(chip, rd->dn);
848 of_node_clear_flag(rd->dn, OF_POPULATED);
849 break;
850 }
851
852 return NOTIFY_OK;
853}
854
855struct notifier_block gpio_of_notifier = {
856 .notifier_call = of_gpio_notify,
857};
858#endif /* CONFIG_OF_DYNAMIC */
859
860/**
861 * of_gpio_simple_xlate - translate gpiospec to the GPIO number and flags
862 * @gc: pointer to the gpio_chip structure
863 * @gpiospec: GPIO specifier as found in the device tree
864 * @flags: a flags pointer to fill in
865 *
866 * This is simple translation function, suitable for the most 1:1 mapped
867 * GPIO chips. This function performs only one sanity check: whether GPIO
868 * is less than ngpios (that is specified in the gpio_chip).
869 */
870static int of_gpio_simple_xlate(struct gpio_chip *gc,
871 const struct of_phandle_args *gpiospec,
872 u32 *flags)
873{
874 /*
875 * We're discouraging gpio_cells < 2, since that way you'll have to
876 * write your own xlate function (that will have to retrieve the GPIO
877 * number and the flags from a single gpio cell -- this is possible,
878 * but not recommended).
879 */
880 if (gc->of_gpio_n_cells < 2) {
881 WARN_ON(1);
882 return -EINVAL;
883 }
884
885 if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
886 return -EINVAL;
887
888 if (gpiospec->args[0] >= gc->ngpio)
889 return -EINVAL;
890
891 if (flags)
892 *flags = gpiospec->args[1];
893
894 return gpiospec->args[0];
895}
896
897/**
898 * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank)
899 * @np: device node of the GPIO chip
900 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure
901 * @data: driver data to store in the struct gpio_chip
902 *
903 * To use this function you should allocate and fill mm_gc with:
904 *
905 * 1) In the gpio_chip structure:
906 * - all the callbacks
907 * - of_gpio_n_cells
908 * - of_xlate callback (optional)
909 *
910 * 3) In the of_mm_gpio_chip structure:
911 * - save_regs callback (optional)
912 *
913 * If succeeded, this function will map bank's memory and will
914 * do all necessary work for you. Then you'll able to use .regs
915 * to manage GPIOs from the callbacks.
916 */
917int of_mm_gpiochip_add_data(struct device_node *np,
918 struct of_mm_gpio_chip *mm_gc,
919 void *data)
920{
921 int ret = -ENOMEM;
922 struct gpio_chip *gc = &mm_gc->gc;
923
924 gc->label = kasprintf(GFP_KERNEL, "%pOF", np);
925 if (!gc->label)
926 goto err0;
927
928 mm_gc->regs = of_iomap(np, 0);
929 if (!mm_gc->regs)
930 goto err1;
931
932 gc->base = -1;
933
934 if (mm_gc->save_regs)
935 mm_gc->save_regs(mm_gc);
936
937 fwnode_handle_put(mm_gc->gc.fwnode);
938 mm_gc->gc.fwnode = fwnode_handle_get(of_fwnode_handle(np));
939
940 ret = gpiochip_add_data(gc, data);
941 if (ret)
942 goto err2;
943
944 return 0;
945err2:
946 of_node_put(np);
947 iounmap(mm_gc->regs);
948err1:
949 kfree(gc->label);
950err0:
951 pr_err("%pOF: GPIO chip registration failed with status %d\n", np, ret);
952 return ret;
953}
954EXPORT_SYMBOL_GPL(of_mm_gpiochip_add_data);
955
956/**
957 * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank)
958 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure
959 */
960void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc)
961{
962 struct gpio_chip *gc = &mm_gc->gc;
963
964 gpiochip_remove(gc);
965 iounmap(mm_gc->regs);
966 kfree(gc->label);
967}
968EXPORT_SYMBOL_GPL(of_mm_gpiochip_remove);
969
970#ifdef CONFIG_PINCTRL
971static int of_gpiochip_add_pin_range(struct gpio_chip *chip)
972{
973 struct device_node *np = chip->of_node;
974 struct of_phandle_args pinspec;
975 struct pinctrl_dev *pctldev;
976 int index = 0, ret;
977 const char *name;
978 static const char group_names_propname[] = "gpio-ranges-group-names";
979 struct property *group_names;
980
981 if (!np)
982 return 0;
983
984 if (!of_property_read_bool(np, "gpio-ranges") &&
985 chip->of_gpio_ranges_fallback) {
986 return chip->of_gpio_ranges_fallback(chip, np);
987 }
988
989 group_names = of_find_property(np, group_names_propname, NULL);
990
991 for (;; index++) {
992 ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3,
993 index, &pinspec);
994 if (ret)
995 break;
996
997 pctldev = of_pinctrl_get(pinspec.np);
998 of_node_put(pinspec.np);
999 if (!pctldev)
1000 return -EPROBE_DEFER;
1001
1002 if (pinspec.args[2]) {
1003 if (group_names) {
1004 of_property_read_string_index(np,
1005 group_names_propname,
1006 index, &name);
1007 if (strlen(name)) {
1008 pr_err("%pOF: Group name of numeric GPIO ranges must be the empty string.\n",
1009 np);
1010 break;
1011 }
1012 }
1013 /* npins != 0: linear range */
1014 ret = gpiochip_add_pin_range(chip,
1015 pinctrl_dev_get_devname(pctldev),
1016 pinspec.args[0],
1017 pinspec.args[1],
1018 pinspec.args[2]);
1019 if (ret)
1020 return ret;
1021 } else {
1022 /* npins == 0: special range */
1023 if (pinspec.args[1]) {
1024 pr_err("%pOF: Illegal gpio-range format.\n",
1025 np);
1026 break;
1027 }
1028
1029 if (!group_names) {
1030 pr_err("%pOF: GPIO group range requested but no %s property.\n",
1031 np, group_names_propname);
1032 break;
1033 }
1034
1035 ret = of_property_read_string_index(np,
1036 group_names_propname,
1037 index, &name);
1038 if (ret)
1039 break;
1040
1041 if (!strlen(name)) {
1042 pr_err("%pOF: Group name of GPIO group range cannot be the empty string.\n",
1043 np);
1044 break;
1045 }
1046
1047 ret = gpiochip_add_pingroup_range(chip, pctldev,
1048 pinspec.args[0], name);
1049 if (ret)
1050 return ret;
1051 }
1052 }
1053
1054 return 0;
1055}
1056
1057#else
1058static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; }
1059#endif
1060
1061int of_gpiochip_add(struct gpio_chip *chip)
1062{
1063 struct device_node *np;
1064 int ret;
1065
1066 np = to_of_node(dev_fwnode(&chip->gpiodev->dev));
1067 if (!np)
1068 return 0;
1069
1070 if (!chip->of_xlate) {
1071 chip->of_gpio_n_cells = 2;
1072 chip->of_xlate = of_gpio_simple_xlate;
1073 }
1074
1075 if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS)
1076 return -EINVAL;
1077
1078 ret = of_gpiochip_add_pin_range(chip);
1079 if (ret)
1080 return ret;
1081
1082 fwnode_handle_get(chip->fwnode);
1083
1084 ret = of_gpiochip_scan_gpios(chip);
1085 if (ret)
1086 fwnode_handle_put(chip->fwnode);
1087
1088 return ret;
1089}
1090
1091void of_gpiochip_remove(struct gpio_chip *chip)
1092{
1093 fwnode_handle_put(chip->fwnode);
1094}
1095
1096void of_gpio_dev_init(struct gpio_chip *gc, struct gpio_device *gdev)
1097{
1098 /* Set default OF node to parent's one if present */
1099 if (gc->parent)
1100 gdev->dev.of_node = gc->parent->of_node;
1101
1102 if (gc->fwnode)
1103 gc->of_node = to_of_node(gc->fwnode);
1104
1105 /* If the gpiochip has an assigned OF node this takes precedence */
1106 if (gc->of_node)
1107 gdev->dev.of_node = gc->of_node;
1108 else
1109 gc->of_node = gdev->dev.of_node;
1110}
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/module.h>
14#include <linux/io.h>
15#include <linux/gpio/consumer.h>
16#include <linux/of.h>
17#include <linux/of_address.h>
18#include <linux/of_gpio.h>
19#include <linux/pinctrl/pinctrl.h>
20#include <linux/slab.h>
21#include <linux/gpio/machine.h>
22
23#include "gpiolib.h"
24#include "gpiolib-of.h"
25
26/*
27 * This is used by external users of of_gpio_count() from <linux/of_gpio.h>
28 *
29 * FIXME: get rid of those external users by converting them to GPIO
30 * descriptors and let them all use gpiod_get_count()
31 */
32int of_gpio_get_count(struct device *dev, const char *con_id)
33{
34 int ret;
35 char propname[32];
36 unsigned int i;
37
38 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
39 if (con_id)
40 snprintf(propname, sizeof(propname), "%s-%s",
41 con_id, gpio_suffixes[i]);
42 else
43 snprintf(propname, sizeof(propname), "%s",
44 gpio_suffixes[i]);
45
46 ret = of_gpio_named_count(dev->of_node, propname);
47 if (ret > 0)
48 break;
49 }
50 return ret ? ret : -ENOENT;
51}
52
53static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip, void *data)
54{
55 struct of_phandle_args *gpiospec = data;
56
57 return chip->gpiodev->dev.of_node == gpiospec->np &&
58 chip->of_xlate &&
59 chip->of_xlate(chip, gpiospec, NULL) >= 0;
60}
61
62static struct gpio_chip *of_find_gpiochip_by_xlate(
63 struct of_phandle_args *gpiospec)
64{
65 return gpiochip_find(gpiospec, of_gpiochip_match_node_and_xlate);
66}
67
68static struct gpio_desc *of_xlate_and_get_gpiod_flags(struct gpio_chip *chip,
69 struct of_phandle_args *gpiospec,
70 enum of_gpio_flags *flags)
71{
72 int ret;
73
74 if (chip->of_gpio_n_cells != gpiospec->args_count)
75 return ERR_PTR(-EINVAL);
76
77 ret = chip->of_xlate(chip, gpiospec, flags);
78 if (ret < 0)
79 return ERR_PTR(ret);
80
81 return gpiochip_get_desc(chip, ret);
82}
83
84/**
85 * of_gpio_need_valid_mask() - figure out if the OF GPIO driver needs
86 * to set the .valid_mask
87 * @dev: the device for the GPIO provider
88 * @return: true if the valid mask needs to be set
89 */
90bool of_gpio_need_valid_mask(const struct gpio_chip *gc)
91{
92 int size;
93 struct device_node *np = gc->of_node;
94
95 size = of_property_count_u32_elems(np, "gpio-reserved-ranges");
96 if (size > 0 && size % 2 == 0)
97 return true;
98 return false;
99}
100
101static void of_gpio_flags_quirks(struct device_node *np,
102 const char *propname,
103 enum of_gpio_flags *flags,
104 int index)
105{
106 /*
107 * Handle MMC "cd-inverted" and "wp-inverted" semantics.
108 */
109 if (IS_ENABLED(CONFIG_MMC)) {
110 /*
111 * Active low is the default according to the
112 * SDHCI specification and the device tree
113 * bindings. However the code in the current
114 * kernel was written such that the phandle
115 * flags were always respected, and "cd-inverted"
116 * would invert the flag from the device phandle.
117 */
118 if (!strcmp(propname, "cd-gpios")) {
119 if (of_property_read_bool(np, "cd-inverted"))
120 *flags ^= OF_GPIO_ACTIVE_LOW;
121 }
122 if (!strcmp(propname, "wp-gpios")) {
123 if (of_property_read_bool(np, "wp-inverted"))
124 *flags ^= OF_GPIO_ACTIVE_LOW;
125 }
126 }
127 /*
128 * Some GPIO fixed regulator quirks.
129 * Note that active low is the default.
130 */
131 if (IS_ENABLED(CONFIG_REGULATOR) &&
132 (of_device_is_compatible(np, "regulator-fixed") ||
133 of_device_is_compatible(np, "reg-fixed-voltage") ||
134 (!(strcmp(propname, "enable-gpio") &&
135 strcmp(propname, "enable-gpios")) &&
136 of_device_is_compatible(np, "regulator-gpio")))) {
137 /*
138 * The regulator GPIO handles are specified such that the
139 * presence or absence of "enable-active-high" solely controls
140 * the polarity of the GPIO line. Any phandle flags must
141 * be actively ignored.
142 */
143 if (*flags & OF_GPIO_ACTIVE_LOW) {
144 pr_warn("%s GPIO handle specifies active low - ignored\n",
145 of_node_full_name(np));
146 *flags &= ~OF_GPIO_ACTIVE_LOW;
147 }
148 if (!of_property_read_bool(np, "enable-active-high"))
149 *flags |= OF_GPIO_ACTIVE_LOW;
150 }
151 /*
152 * Legacy open drain handling for fixed voltage regulators.
153 */
154 if (IS_ENABLED(CONFIG_REGULATOR) &&
155 of_device_is_compatible(np, "reg-fixed-voltage") &&
156 of_property_read_bool(np, "gpio-open-drain")) {
157 *flags |= (OF_GPIO_SINGLE_ENDED | OF_GPIO_OPEN_DRAIN);
158 pr_info("%s uses legacy open drain flag - update the DTS if you can\n",
159 of_node_full_name(np));
160 }
161
162 /*
163 * Legacy handling of SPI active high chip select. If we have a
164 * property named "cs-gpios" we need to inspect the child node
165 * to determine if the flags should have inverted semantics.
166 */
167 if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") &&
168 of_property_read_bool(np, "cs-gpios")) {
169 struct device_node *child;
170 u32 cs;
171 int ret;
172
173 for_each_child_of_node(np, child) {
174 ret = of_property_read_u32(child, "reg", &cs);
175 if (ret)
176 continue;
177 if (cs == index) {
178 /*
179 * SPI children have active low chip selects
180 * by default. This can be specified negatively
181 * by just omitting "spi-cs-high" in the
182 * device node, or actively by tagging on
183 * GPIO_ACTIVE_LOW as flag in the device
184 * tree. If the line is simultaneously
185 * tagged as active low in the device tree
186 * and has the "spi-cs-high" set, we get a
187 * conflict and the "spi-cs-high" flag will
188 * take precedence.
189 */
190 if (of_property_read_bool(child, "spi-cs-high")) {
191 if (*flags & OF_GPIO_ACTIVE_LOW) {
192 pr_warn("%s GPIO handle specifies active low - ignored\n",
193 of_node_full_name(child));
194 *flags &= ~OF_GPIO_ACTIVE_LOW;
195 }
196 } else {
197 if (!(*flags & OF_GPIO_ACTIVE_LOW))
198 pr_info("%s enforce active low on chipselect handle\n",
199 of_node_full_name(child));
200 *flags |= OF_GPIO_ACTIVE_LOW;
201 }
202 of_node_put(child);
203 break;
204 }
205 }
206 }
207
208 /* Legacy handling of stmmac's active-low PHY reset line */
209 if (IS_ENABLED(CONFIG_STMMAC_ETH) &&
210 !strcmp(propname, "snps,reset-gpio") &&
211 of_property_read_bool(np, "snps,reset-active-low"))
212 *flags |= OF_GPIO_ACTIVE_LOW;
213}
214
215/**
216 * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API
217 * @np: device node to get GPIO from
218 * @propname: property name containing gpio specifier(s)
219 * @index: index of the GPIO
220 * @flags: a flags pointer to fill in
221 *
222 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
223 * value on the error condition. If @flags is not NULL the function also fills
224 * in flags for the GPIO.
225 */
226static struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
227 const char *propname, int index, enum of_gpio_flags *flags)
228{
229 struct of_phandle_args gpiospec;
230 struct gpio_chip *chip;
231 struct gpio_desc *desc;
232 int ret;
233
234 ret = of_parse_phandle_with_args_map(np, propname, "gpio", index,
235 &gpiospec);
236 if (ret) {
237 pr_debug("%s: can't parse '%s' property of node '%pOF[%d]'\n",
238 __func__, propname, np, index);
239 return ERR_PTR(ret);
240 }
241
242 chip = of_find_gpiochip_by_xlate(&gpiospec);
243 if (!chip) {
244 desc = ERR_PTR(-EPROBE_DEFER);
245 goto out;
246 }
247
248 desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, flags);
249 if (IS_ERR(desc))
250 goto out;
251
252 if (flags)
253 of_gpio_flags_quirks(np, propname, flags, index);
254
255 pr_debug("%s: parsed '%s' property of node '%pOF[%d]' - status (%d)\n",
256 __func__, propname, np, index,
257 PTR_ERR_OR_ZERO(desc));
258
259out:
260 of_node_put(gpiospec.np);
261
262 return desc;
263}
264
265int of_get_named_gpio_flags(struct device_node *np, const char *list_name,
266 int index, enum of_gpio_flags *flags)
267{
268 struct gpio_desc *desc;
269
270 desc = of_get_named_gpiod_flags(np, list_name, index, flags);
271
272 if (IS_ERR(desc))
273 return PTR_ERR(desc);
274 else
275 return desc_to_gpio(desc);
276}
277EXPORT_SYMBOL_GPL(of_get_named_gpio_flags);
278
279/**
280 * gpiod_get_from_of_node() - obtain a GPIO from an OF node
281 * @node: handle of the OF node
282 * @propname: name of the DT property representing the GPIO
283 * @index: index of the GPIO to obtain for the consumer
284 * @dflags: GPIO initialization flags
285 * @label: label to attach to the requested GPIO
286 *
287 * Returns:
288 * On successful request the GPIO pin is configured in accordance with
289 * provided @dflags.
290 *
291 * In case of error an ERR_PTR() is returned.
292 */
293struct gpio_desc *gpiod_get_from_of_node(struct device_node *node,
294 const char *propname, int index,
295 enum gpiod_flags dflags,
296 const char *label)
297{
298 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
299 struct gpio_desc *desc;
300 enum of_gpio_flags flags;
301 bool active_low = false;
302 bool single_ended = false;
303 bool open_drain = false;
304 bool transitory = false;
305 int ret;
306
307 desc = of_get_named_gpiod_flags(node, propname,
308 index, &flags);
309
310 if (!desc || IS_ERR(desc)) {
311 return desc;
312 }
313
314 active_low = flags & OF_GPIO_ACTIVE_LOW;
315 single_ended = flags & OF_GPIO_SINGLE_ENDED;
316 open_drain = flags & OF_GPIO_OPEN_DRAIN;
317 transitory = flags & OF_GPIO_TRANSITORY;
318
319 ret = gpiod_request(desc, label);
320 if (ret == -EBUSY && (dflags & GPIOD_FLAGS_BIT_NONEXCLUSIVE))
321 return desc;
322 if (ret)
323 return ERR_PTR(ret);
324
325 if (active_low)
326 lflags |= GPIO_ACTIVE_LOW;
327
328 if (single_ended) {
329 if (open_drain)
330 lflags |= GPIO_OPEN_DRAIN;
331 else
332 lflags |= GPIO_OPEN_SOURCE;
333 }
334
335 if (transitory)
336 lflags |= GPIO_TRANSITORY;
337
338 ret = gpiod_configure_flags(desc, propname, lflags, dflags);
339 if (ret < 0) {
340 gpiod_put(desc);
341 return ERR_PTR(ret);
342 }
343
344 return desc;
345}
346EXPORT_SYMBOL_GPL(gpiod_get_from_of_node);
347
348/*
349 * The SPI GPIO bindings happened before we managed to establish that GPIO
350 * properties should be named "foo-gpios" so we have this special kludge for
351 * them.
352 */
353static struct gpio_desc *of_find_spi_gpio(struct device *dev, const char *con_id,
354 enum of_gpio_flags *of_flags)
355{
356 char prop_name[32]; /* 32 is max size of property name */
357 struct device_node *np = dev->of_node;
358 struct gpio_desc *desc;
359
360 /*
361 * Hopefully the compiler stubs the rest of the function if this
362 * is false.
363 */
364 if (!IS_ENABLED(CONFIG_SPI_MASTER))
365 return ERR_PTR(-ENOENT);
366
367 /* Allow this specifically for "spi-gpio" devices */
368 if (!of_device_is_compatible(np, "spi-gpio") || !con_id)
369 return ERR_PTR(-ENOENT);
370
371 /* Will be "gpio-sck", "gpio-mosi" or "gpio-miso" */
372 snprintf(prop_name, sizeof(prop_name), "%s-%s", "gpio", con_id);
373
374 desc = of_get_named_gpiod_flags(np, prop_name, 0, of_flags);
375 return desc;
376}
377
378/*
379 * The old Freescale bindings use simply "gpios" as name for the chip select
380 * lines rather than "cs-gpios" like all other SPI hardware. Account for this
381 * with a special quirk.
382 */
383static struct gpio_desc *of_find_spi_cs_gpio(struct device *dev,
384 const char *con_id,
385 unsigned int idx,
386 unsigned long *flags)
387{
388 struct device_node *np = dev->of_node;
389
390 if (!IS_ENABLED(CONFIG_SPI_MASTER))
391 return ERR_PTR(-ENOENT);
392
393 /* Allow this specifically for Freescale devices */
394 if (!of_device_is_compatible(np, "fsl,spi") &&
395 !of_device_is_compatible(np, "aeroflexgaisler,spictrl"))
396 return ERR_PTR(-ENOENT);
397 /* Allow only if asking for "cs-gpios" */
398 if (!con_id || strcmp(con_id, "cs"))
399 return ERR_PTR(-ENOENT);
400
401 /*
402 * While all other SPI controllers use "cs-gpios" the Freescale
403 * uses just "gpios" so translate to that when "cs-gpios" is
404 * requested.
405 */
406 return of_find_gpio(dev, NULL, idx, flags);
407}
408
409/*
410 * Some regulator bindings happened before we managed to establish that GPIO
411 * properties should be named "foo-gpios" so we have this special kludge for
412 * them.
413 */
414static struct gpio_desc *of_find_regulator_gpio(struct device *dev, const char *con_id,
415 enum of_gpio_flags *of_flags)
416{
417 /* These are the connection IDs we accept as legacy GPIO phandles */
418 const char *whitelist[] = {
419 "wlf,ldoena", /* Arizona */
420 "wlf,ldo1ena", /* WM8994 */
421 "wlf,ldo2ena", /* WM8994 */
422 };
423 struct device_node *np = dev->of_node;
424 struct gpio_desc *desc;
425 int i;
426
427 if (!IS_ENABLED(CONFIG_REGULATOR))
428 return ERR_PTR(-ENOENT);
429
430 if (!con_id)
431 return ERR_PTR(-ENOENT);
432
433 i = match_string(whitelist, ARRAY_SIZE(whitelist), con_id);
434 if (i < 0)
435 return ERR_PTR(-ENOENT);
436
437 desc = of_get_named_gpiod_flags(np, con_id, 0, of_flags);
438 return desc;
439}
440
441static struct gpio_desc *of_find_arizona_gpio(struct device *dev,
442 const char *con_id,
443 enum of_gpio_flags *of_flags)
444{
445 if (!IS_ENABLED(CONFIG_MFD_ARIZONA))
446 return ERR_PTR(-ENOENT);
447
448 if (!con_id || strcmp(con_id, "wlf,reset"))
449 return ERR_PTR(-ENOENT);
450
451 return of_get_named_gpiod_flags(dev->of_node, con_id, 0, of_flags);
452}
453
454struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
455 unsigned int idx, unsigned long *flags)
456{
457 char prop_name[32]; /* 32 is max size of property name */
458 enum of_gpio_flags of_flags;
459 struct gpio_desc *desc;
460 unsigned int i;
461
462 /* Try GPIO property "foo-gpios" and "foo-gpio" */
463 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
464 if (con_id)
465 snprintf(prop_name, sizeof(prop_name), "%s-%s", con_id,
466 gpio_suffixes[i]);
467 else
468 snprintf(prop_name, sizeof(prop_name), "%s",
469 gpio_suffixes[i]);
470
471 desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx,
472 &of_flags);
473
474 if (!IS_ERR(desc) || PTR_ERR(desc) != -ENOENT)
475 break;
476 }
477
478 if (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT) {
479 /* Special handling for SPI GPIOs if used */
480 desc = of_find_spi_gpio(dev, con_id, &of_flags);
481 }
482
483 if (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT) {
484 /* This quirk looks up flags and all */
485 desc = of_find_spi_cs_gpio(dev, con_id, idx, flags);
486 if (!IS_ERR(desc))
487 return desc;
488 }
489
490 if (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT) {
491 /* Special handling for regulator GPIOs if used */
492 desc = of_find_regulator_gpio(dev, con_id, &of_flags);
493 }
494
495 if (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT)
496 desc = of_find_arizona_gpio(dev, con_id, &of_flags);
497
498 if (IS_ERR(desc))
499 return desc;
500
501 if (of_flags & OF_GPIO_ACTIVE_LOW)
502 *flags |= GPIO_ACTIVE_LOW;
503
504 if (of_flags & OF_GPIO_SINGLE_ENDED) {
505 if (of_flags & OF_GPIO_OPEN_DRAIN)
506 *flags |= GPIO_OPEN_DRAIN;
507 else
508 *flags |= GPIO_OPEN_SOURCE;
509 }
510
511 if (of_flags & OF_GPIO_TRANSITORY)
512 *flags |= GPIO_TRANSITORY;
513
514 if (of_flags & OF_GPIO_PULL_UP)
515 *flags |= GPIO_PULL_UP;
516 if (of_flags & OF_GPIO_PULL_DOWN)
517 *flags |= GPIO_PULL_DOWN;
518
519 return desc;
520}
521
522/**
523 * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API
524 * @np: device node to get GPIO from
525 * @chip: GPIO chip whose hog is parsed
526 * @idx: Index of the GPIO to parse
527 * @name: GPIO line name
528 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
529 * of_find_gpio() or of_parse_own_gpio()
530 * @dflags: gpiod_flags - optional GPIO initialization flags
531 *
532 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
533 * value on the error condition.
534 */
535static struct gpio_desc *of_parse_own_gpio(struct device_node *np,
536 struct gpio_chip *chip,
537 unsigned int idx, const char **name,
538 unsigned long *lflags,
539 enum gpiod_flags *dflags)
540{
541 struct device_node *chip_np;
542 enum of_gpio_flags xlate_flags;
543 struct of_phandle_args gpiospec;
544 struct gpio_desc *desc;
545 unsigned int i;
546 u32 tmp;
547 int ret;
548
549 chip_np = chip->of_node;
550 if (!chip_np)
551 return ERR_PTR(-EINVAL);
552
553 xlate_flags = 0;
554 *lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
555 *dflags = 0;
556
557 ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp);
558 if (ret)
559 return ERR_PTR(ret);
560
561 gpiospec.np = chip_np;
562 gpiospec.args_count = tmp;
563
564 for (i = 0; i < tmp; i++) {
565 ret = of_property_read_u32_index(np, "gpios", idx * tmp + i,
566 &gpiospec.args[i]);
567 if (ret)
568 return ERR_PTR(ret);
569 }
570
571 desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, &xlate_flags);
572 if (IS_ERR(desc))
573 return desc;
574
575 if (xlate_flags & OF_GPIO_ACTIVE_LOW)
576 *lflags |= GPIO_ACTIVE_LOW;
577 if (xlate_flags & OF_GPIO_TRANSITORY)
578 *lflags |= GPIO_TRANSITORY;
579
580 if (of_property_read_bool(np, "input"))
581 *dflags |= GPIOD_IN;
582 else if (of_property_read_bool(np, "output-low"))
583 *dflags |= GPIOD_OUT_LOW;
584 else if (of_property_read_bool(np, "output-high"))
585 *dflags |= GPIOD_OUT_HIGH;
586 else {
587 pr_warn("GPIO line %d (%pOFn): no hogging state specified, bailing out\n",
588 desc_to_gpio(desc), np);
589 return ERR_PTR(-EINVAL);
590 }
591
592 if (name && of_property_read_string(np, "line-name", name))
593 *name = np->name;
594
595 return desc;
596}
597
598/**
599 * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions
600 * @chip: gpio chip to act on
601 *
602 * This is only used by of_gpiochip_add to request/set GPIO initial
603 * configuration.
604 * It returns error if it fails otherwise 0 on success.
605 */
606static int of_gpiochip_scan_gpios(struct gpio_chip *chip)
607{
608 struct gpio_desc *desc = NULL;
609 struct device_node *np;
610 const char *name;
611 unsigned long lflags;
612 enum gpiod_flags dflags;
613 unsigned int i;
614 int ret;
615
616 for_each_available_child_of_node(chip->of_node, np) {
617 if (!of_property_read_bool(np, "gpio-hog"))
618 continue;
619
620 for (i = 0;; i++) {
621 desc = of_parse_own_gpio(np, chip, i, &name, &lflags,
622 &dflags);
623 if (IS_ERR(desc))
624 break;
625
626 ret = gpiod_hog(desc, name, lflags, dflags);
627 if (ret < 0) {
628 of_node_put(np);
629 return ret;
630 }
631 }
632 }
633
634 return 0;
635}
636
637/**
638 * of_gpio_simple_xlate - translate gpiospec to the GPIO number and flags
639 * @gc: pointer to the gpio_chip structure
640 * @gpiospec: GPIO specifier as found in the device tree
641 * @flags: a flags pointer to fill in
642 *
643 * This is simple translation function, suitable for the most 1:1 mapped
644 * GPIO chips. This function performs only one sanity check: whether GPIO
645 * is less than ngpios (that is specified in the gpio_chip).
646 */
647static int of_gpio_simple_xlate(struct gpio_chip *gc,
648 const struct of_phandle_args *gpiospec,
649 u32 *flags)
650{
651 /*
652 * We're discouraging gpio_cells < 2, since that way you'll have to
653 * write your own xlate function (that will have to retrieve the GPIO
654 * number and the flags from a single gpio cell -- this is possible,
655 * but not recommended).
656 */
657 if (gc->of_gpio_n_cells < 2) {
658 WARN_ON(1);
659 return -EINVAL;
660 }
661
662 if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
663 return -EINVAL;
664
665 if (gpiospec->args[0] >= gc->ngpio)
666 return -EINVAL;
667
668 if (flags)
669 *flags = gpiospec->args[1];
670
671 return gpiospec->args[0];
672}
673
674/**
675 * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank)
676 * @np: device node of the GPIO chip
677 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure
678 * @data: driver data to store in the struct gpio_chip
679 *
680 * To use this function you should allocate and fill mm_gc with:
681 *
682 * 1) In the gpio_chip structure:
683 * - all the callbacks
684 * - of_gpio_n_cells
685 * - of_xlate callback (optional)
686 *
687 * 3) In the of_mm_gpio_chip structure:
688 * - save_regs callback (optional)
689 *
690 * If succeeded, this function will map bank's memory and will
691 * do all necessary work for you. Then you'll able to use .regs
692 * to manage GPIOs from the callbacks.
693 */
694int of_mm_gpiochip_add_data(struct device_node *np,
695 struct of_mm_gpio_chip *mm_gc,
696 void *data)
697{
698 int ret = -ENOMEM;
699 struct gpio_chip *gc = &mm_gc->gc;
700
701 gc->label = kasprintf(GFP_KERNEL, "%pOF", np);
702 if (!gc->label)
703 goto err0;
704
705 mm_gc->regs = of_iomap(np, 0);
706 if (!mm_gc->regs)
707 goto err1;
708
709 gc->base = -1;
710
711 if (mm_gc->save_regs)
712 mm_gc->save_regs(mm_gc);
713
714 mm_gc->gc.of_node = np;
715
716 ret = gpiochip_add_data(gc, data);
717 if (ret)
718 goto err2;
719
720 return 0;
721err2:
722 iounmap(mm_gc->regs);
723err1:
724 kfree(gc->label);
725err0:
726 pr_err("%pOF: GPIO chip registration failed with status %d\n", np, ret);
727 return ret;
728}
729EXPORT_SYMBOL_GPL(of_mm_gpiochip_add_data);
730
731/**
732 * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank)
733 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure
734 */
735void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc)
736{
737 struct gpio_chip *gc = &mm_gc->gc;
738
739 if (!mm_gc)
740 return;
741
742 gpiochip_remove(gc);
743 iounmap(mm_gc->regs);
744 kfree(gc->label);
745}
746EXPORT_SYMBOL_GPL(of_mm_gpiochip_remove);
747
748static void of_gpiochip_init_valid_mask(struct gpio_chip *chip)
749{
750 int len, i;
751 u32 start, count;
752 struct device_node *np = chip->of_node;
753
754 len = of_property_count_u32_elems(np, "gpio-reserved-ranges");
755 if (len < 0 || len % 2 != 0)
756 return;
757
758 for (i = 0; i < len; i += 2) {
759 of_property_read_u32_index(np, "gpio-reserved-ranges",
760 i, &start);
761 of_property_read_u32_index(np, "gpio-reserved-ranges",
762 i + 1, &count);
763 if (start >= chip->ngpio || start + count >= chip->ngpio)
764 continue;
765
766 bitmap_clear(chip->valid_mask, start, count);
767 }
768};
769
770#ifdef CONFIG_PINCTRL
771static int of_gpiochip_add_pin_range(struct gpio_chip *chip)
772{
773 struct device_node *np = chip->of_node;
774 struct of_phandle_args pinspec;
775 struct pinctrl_dev *pctldev;
776 int index = 0, ret;
777 const char *name;
778 static const char group_names_propname[] = "gpio-ranges-group-names";
779 struct property *group_names;
780
781 if (!np)
782 return 0;
783
784 group_names = of_find_property(np, group_names_propname, NULL);
785
786 for (;; index++) {
787 ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3,
788 index, &pinspec);
789 if (ret)
790 break;
791
792 pctldev = of_pinctrl_get(pinspec.np);
793 of_node_put(pinspec.np);
794 if (!pctldev)
795 return -EPROBE_DEFER;
796
797 if (pinspec.args[2]) {
798 if (group_names) {
799 of_property_read_string_index(np,
800 group_names_propname,
801 index, &name);
802 if (strlen(name)) {
803 pr_err("%pOF: Group name of numeric GPIO ranges must be the empty string.\n",
804 np);
805 break;
806 }
807 }
808 /* npins != 0: linear range */
809 ret = gpiochip_add_pin_range(chip,
810 pinctrl_dev_get_devname(pctldev),
811 pinspec.args[0],
812 pinspec.args[1],
813 pinspec.args[2]);
814 if (ret)
815 return ret;
816 } else {
817 /* npins == 0: special range */
818 if (pinspec.args[1]) {
819 pr_err("%pOF: Illegal gpio-range format.\n",
820 np);
821 break;
822 }
823
824 if (!group_names) {
825 pr_err("%pOF: GPIO group range requested but no %s property.\n",
826 np, group_names_propname);
827 break;
828 }
829
830 ret = of_property_read_string_index(np,
831 group_names_propname,
832 index, &name);
833 if (ret)
834 break;
835
836 if (!strlen(name)) {
837 pr_err("%pOF: Group name of GPIO group range cannot be the empty string.\n",
838 np);
839 break;
840 }
841
842 ret = gpiochip_add_pingroup_range(chip, pctldev,
843 pinspec.args[0], name);
844 if (ret)
845 return ret;
846 }
847 }
848
849 return 0;
850}
851
852#else
853static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; }
854#endif
855
856int of_gpiochip_add(struct gpio_chip *chip)
857{
858 int ret;
859
860 if (!chip->of_node)
861 return 0;
862
863 if (!chip->of_xlate) {
864 chip->of_gpio_n_cells = 2;
865 chip->of_xlate = of_gpio_simple_xlate;
866 }
867
868 if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS)
869 return -EINVAL;
870
871 of_gpiochip_init_valid_mask(chip);
872
873 ret = of_gpiochip_add_pin_range(chip);
874 if (ret)
875 return ret;
876
877 /* If the chip defines names itself, these take precedence */
878 if (!chip->names)
879 devprop_gpiochip_set_names(chip,
880 of_fwnode_handle(chip->of_node));
881
882 of_node_get(chip->of_node);
883
884 ret = of_gpiochip_scan_gpios(chip);
885 if (ret) {
886 of_node_put(chip->of_node);
887 gpiochip_remove_pin_ranges(chip);
888 }
889
890 return ret;
891}
892
893void of_gpiochip_remove(struct gpio_chip *chip)
894{
895 gpiochip_remove_pin_ranges(chip);
896 of_node_put(chip->of_node);
897}