1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * OF helpers for the GPIO API
4 *
5 * Copyright (c) 2007-2008 MontaVista Software, Inc.
6 *
7 * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
8 */
9
10 #include <linux/device.h>
11 #include <linux/err.h>
12 #include <linux/errno.h>
13 #include <linux/io.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/of_address.h>
17 #include <linux/of_gpio.h>
18 #include <linux/pinctrl/pinctrl.h>
19 #include <linux/slab.h>
20 #include <linux/string.h>
21
22 #include <linux/gpio/consumer.h>
23 #include <linux/gpio/machine.h>
24
25 #include "gpiolib.h"
26 #include "gpiolib-of.h"
27
28 /*
29 * This is Linux-specific flags. By default controllers' and Linux' mapping
30 * match, but GPIO controllers are free to translate their own flags to
31 * Linux-specific in their .xlate callback. Though, 1:1 mapping is recommended.
32 */
33 enum of_gpio_flags {
34 OF_GPIO_ACTIVE_LOW = 0x1,
35 OF_GPIO_SINGLE_ENDED = 0x2,
36 OF_GPIO_OPEN_DRAIN = 0x4,
37 OF_GPIO_TRANSITORY = 0x8,
38 OF_GPIO_PULL_UP = 0x10,
39 OF_GPIO_PULL_DOWN = 0x20,
40 OF_GPIO_PULL_DISABLE = 0x40,
41 };
42
43 /**
44 * of_gpio_named_count() - Count GPIOs for a device
45 * @np: device node to count GPIOs for
46 * @propname: property name containing gpio specifier(s)
47 *
48 * The function returns the count of GPIOs specified for a node.
49 * NOTE: The empty GPIO specifiers count too.
50 *
51 * Returns:
52 * Either number of GPIOs defined in the property, or
53 * * %-EINVAL for an incorrectly formed "gpios" property, or
54 * * %-ENOENT for a missing "gpios" property.
55 *
56 * Example::
57 *
58 * gpios = <0
59 * &gpio1 1 2
60 * 0
61 * &gpio2 3 4>;
62 *
63 * The above example defines four GPIOs, two of which are not specified.
64 * This function will return '4'
65 */
of_gpio_named_count(const struct device_node * np,const char * propname)66 static int of_gpio_named_count(const struct device_node *np,
67 const char *propname)
68 {
69 return of_count_phandle_with_args(np, propname, "#gpio-cells");
70 }
71
72 /**
73 * of_gpio_spi_cs_get_count() - special GPIO counting for SPI
74 * @np: Consuming device node
75 * @con_id: Function within the GPIO consumer
76 *
77 * Some elder GPIO controllers need special quirks. Currently we handle
78 * the Freescale and PPC GPIO controller with bindings that doesn't use the
79 * established "cs-gpios" for chip selects but instead rely on
80 * "gpios" for the chip select lines. If we detect this, we redirect
81 * the counting of "cs-gpios" to count "gpios" transparent to the
82 * driver.
83 *
84 * Returns:
85 * Either number of GPIOs defined in the property, or
86 * * %-EINVAL for an incorrectly formed "gpios" property, or
87 * * %-ENOENT for a missing "gpios" property.
88 */
of_gpio_spi_cs_get_count(const struct device_node * np,const char * con_id)89 static int of_gpio_spi_cs_get_count(const struct device_node *np,
90 const char *con_id)
91 {
92 if (!IS_ENABLED(CONFIG_SPI_MASTER))
93 return 0;
94 if (!con_id || strcmp(con_id, "cs"))
95 return 0;
96 if (!of_device_is_compatible(np, "fsl,spi") &&
97 !of_device_is_compatible(np, "aeroflexgaisler,spictrl") &&
98 !of_device_is_compatible(np, "ibm,ppc4xx-spi"))
99 return 0;
100 return of_gpio_named_count(np, "gpios");
101 }
102
of_gpio_count(const struct fwnode_handle * fwnode,const char * con_id)103 int of_gpio_count(const struct fwnode_handle *fwnode, const char *con_id)
104 {
105 const struct device_node *np = to_of_node(fwnode);
106 int ret;
107 char propname[32];
108
109 ret = of_gpio_spi_cs_get_count(np, con_id);
110 if (ret > 0)
111 return ret;
112
113 for_each_gpio_property_name(propname, con_id) {
114 ret = of_gpio_named_count(np, propname);
115 if (ret > 0)
116 break;
117 }
118 return ret ? ret : -ENOENT;
119 }
120
of_gpiochip_match_node_and_xlate(struct gpio_chip * chip,const void * data)121 static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip,
122 const void *data)
123 {
124 const struct of_phandle_args *gpiospec = data;
125
126 return device_match_of_node(&chip->gpiodev->dev, gpiospec->np) &&
127 chip->of_xlate &&
128 chip->of_xlate(chip, gpiospec, NULL) >= 0;
129 }
130
131 static struct gpio_device *
of_find_gpio_device_by_xlate(const struct of_phandle_args * gpiospec)132 of_find_gpio_device_by_xlate(const struct of_phandle_args *gpiospec)
133 {
134 return gpio_device_find(gpiospec, of_gpiochip_match_node_and_xlate);
135 }
136
of_xlate_and_get_gpiod_flags(struct gpio_chip * chip,struct of_phandle_args * gpiospec,enum of_gpio_flags * flags)137 static struct gpio_desc *of_xlate_and_get_gpiod_flags(struct gpio_chip *chip,
138 struct of_phandle_args *gpiospec,
139 enum of_gpio_flags *flags)
140 {
141 int ret;
142
143 if (chip->of_gpio_n_cells != gpiospec->args_count)
144 return ERR_PTR(-EINVAL);
145
146 ret = chip->of_xlate(chip, gpiospec, flags);
147 if (ret < 0)
148 return ERR_PTR(ret);
149
150 return gpiochip_get_desc(chip, ret);
151 }
152
153 /*
154 * Overrides stated polarity of a gpio line and warns when there is a
155 * discrepancy.
156 */
of_gpio_quirk_polarity(const struct device_node * np,bool active_high,enum of_gpio_flags * flags)157 static void of_gpio_quirk_polarity(const struct device_node *np,
158 bool active_high,
159 enum of_gpio_flags *flags)
160 {
161 if (active_high) {
162 if (*flags & OF_GPIO_ACTIVE_LOW) {
163 pr_warn("%s GPIO handle specifies active low - ignored\n",
164 of_node_full_name(np));
165 *flags &= ~OF_GPIO_ACTIVE_LOW;
166 }
167 } else {
168 if (!(*flags & OF_GPIO_ACTIVE_LOW))
169 pr_info("%s enforce active low on GPIO handle\n",
170 of_node_full_name(np));
171 *flags |= OF_GPIO_ACTIVE_LOW;
172 }
173 }
174
175 /*
176 * This quirk does static polarity overrides in cases where existing
177 * DTS specified incorrect polarity.
178 */
of_gpio_try_fixup_polarity(const struct device_node * np,const char * propname,enum of_gpio_flags * flags)179 static void of_gpio_try_fixup_polarity(const struct device_node *np,
180 const char *propname,
181 enum of_gpio_flags *flags)
182 {
183 static const struct {
184 const char *compatible;
185 const char *propname;
186 bool active_high;
187 } gpios[] = {
188 #if IS_ENABLED(CONFIG_LCD_HX8357)
189 /*
190 * Himax LCD controllers used incorrectly named
191 * "gpios-reset" property and also specified wrong
192 * polarity.
193 */
194 { "himax,hx8357", "gpios-reset", false },
195 { "himax,hx8369", "gpios-reset", false },
196 /*
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 #if IS_ENABLED(CONFIG_PCI_LANTIQ)
207 /*
208 * According to the PCI specification, the RST# pin is an
209 * active-low signal. However, most of the device trees that
210 * have been widely used for a long time incorrectly describe
211 * reset GPIO as active-high, and were also using wrong name
212 * for the property.
213 */
214 { "lantiq,pci-xway", "gpio-reset", false },
215 #endif
216 #if IS_ENABLED(CONFIG_TOUCHSCREEN_TSC2005)
217 /*
218 * DTS for Nokia N900 incorrectly specified "active high"
219 * polarity for the reset line, while the chip actually
220 * treats it as "active low".
221 */
222 { "ti,tsc2005", "reset-gpios", false },
223 #endif
224 };
225 unsigned int i;
226
227 for (i = 0; i < ARRAY_SIZE(gpios); i++) {
228 if (of_device_is_compatible(np, gpios[i].compatible) &&
229 !strcmp(propname, gpios[i].propname)) {
230 of_gpio_quirk_polarity(np, gpios[i].active_high, flags);
231 break;
232 }
233 }
234 }
235
of_gpio_set_polarity_by_property(const struct device_node * np,const char * propname,enum of_gpio_flags * flags)236 static void of_gpio_set_polarity_by_property(const struct device_node *np,
237 const char *propname,
238 enum of_gpio_flags *flags)
239 {
240 const struct device_node *np_compat = np;
241 const struct device_node *np_propname = np;
242 static const struct {
243 const char *compatible;
244 const char *gpio_propname;
245 const char *polarity_propname;
246 } gpios[] = {
247 #if IS_ENABLED(CONFIG_FEC)
248 /* Freescale Fast Ethernet Controller */
249 { "fsl,imx25-fec", "phy-reset-gpios", "phy-reset-active-high" },
250 { "fsl,imx27-fec", "phy-reset-gpios", "phy-reset-active-high" },
251 { "fsl,imx28-fec", "phy-reset-gpios", "phy-reset-active-high" },
252 { "fsl,imx6q-fec", "phy-reset-gpios", "phy-reset-active-high" },
253 { "fsl,mvf600-fec", "phy-reset-gpios", "phy-reset-active-high" },
254 { "fsl,imx6sx-fec", "phy-reset-gpios", "phy-reset-active-high" },
255 { "fsl,imx6ul-fec", "phy-reset-gpios", "phy-reset-active-high" },
256 { "fsl,imx8mq-fec", "phy-reset-gpios", "phy-reset-active-high" },
257 { "fsl,imx8qm-fec", "phy-reset-gpios", "phy-reset-active-high" },
258 { "fsl,s32v234-fec", "phy-reset-gpios", "phy-reset-active-high" },
259 #endif
260 #if IS_ENABLED(CONFIG_PCI_IMX6)
261 { "fsl,imx6q-pcie", "reset-gpio", "reset-gpio-active-high" },
262 { "fsl,imx6sx-pcie", "reset-gpio", "reset-gpio-active-high" },
263 { "fsl,imx6qp-pcie", "reset-gpio", "reset-gpio-active-high" },
264 { "fsl,imx7d-pcie", "reset-gpio", "reset-gpio-active-high" },
265 { "fsl,imx8mq-pcie", "reset-gpio", "reset-gpio-active-high" },
266 { "fsl,imx8mm-pcie", "reset-gpio", "reset-gpio-active-high" },
267 { "fsl,imx8mp-pcie", "reset-gpio", "reset-gpio-active-high" },
268 #endif
269
270 /*
271 * The regulator GPIO handles are specified such that the
272 * presence or absence of "enable-active-high" solely controls
273 * the polarity of the GPIO line. Any phandle flags must
274 * be actively ignored.
275 */
276 #if IS_ENABLED(CONFIG_REGULATOR_FIXED_VOLTAGE)
277 { "regulator-fixed", "gpios", "enable-active-high" },
278 { "regulator-fixed", "gpio", "enable-active-high" },
279 { "reg-fixed-voltage", "gpios", "enable-active-high" },
280 { "reg-fixed-voltage", "gpio", "enable-active-high" },
281 #endif
282 #if IS_ENABLED(CONFIG_REGULATOR_GPIO)
283 { "regulator-gpio", "enable-gpio", "enable-active-high" },
284 { "regulator-gpio", "enable-gpios", "enable-active-high" },
285 #endif
286 #if IS_ENABLED(CONFIG_MMC_ATMELMCI)
287 { "atmel,hsmci", "cd-gpios", "cd-inverted" },
288 #endif
289 };
290 unsigned int i;
291 bool active_high;
292
293 #if IS_ENABLED(CONFIG_MMC_ATMELMCI)
294 /*
295 * The Atmel HSMCI has compatible property in the parent node and
296 * gpio property in a child node
297 */
298 if (of_device_is_compatible(np->parent, "atmel,hsmci")) {
299 np_compat = np->parent;
300 np_propname = np;
301 }
302 #endif
303
304 for (i = 0; i < ARRAY_SIZE(gpios); i++) {
305 if (of_device_is_compatible(np_compat, gpios[i].compatible) &&
306 !strcmp(propname, gpios[i].gpio_propname)) {
307 active_high = of_property_read_bool(np_propname,
308 gpios[i].polarity_propname);
309 of_gpio_quirk_polarity(np, active_high, flags);
310 break;
311 }
312 }
313 }
314
of_gpio_flags_quirks(const struct device_node * np,const char * propname,enum of_gpio_flags * flags,int index)315 static void of_gpio_flags_quirks(const struct device_node *np,
316 const char *propname,
317 enum of_gpio_flags *flags,
318 int index)
319 {
320 of_gpio_try_fixup_polarity(np, propname, flags);
321 of_gpio_set_polarity_by_property(np, propname, flags);
322
323 /*
324 * Legacy open drain handling for fixed voltage regulators.
325 */
326 if (IS_ENABLED(CONFIG_REGULATOR) &&
327 of_device_is_compatible(np, "reg-fixed-voltage") &&
328 of_property_read_bool(np, "gpio-open-drain")) {
329 *flags |= (OF_GPIO_SINGLE_ENDED | OF_GPIO_OPEN_DRAIN);
330 pr_info("%s uses legacy open drain flag - update the DTS if you can\n",
331 of_node_full_name(np));
332 }
333
334 /*
335 * Legacy handling of SPI active high chip select. If we have a
336 * property named "cs-gpios" we need to inspect the child node
337 * to determine if the flags should have inverted semantics.
338 */
339 if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") &&
340 of_property_read_bool(np, "cs-gpios")) {
341 u32 cs;
342 int ret;
343
344 for_each_child_of_node_scoped(np, child) {
345 ret = of_property_read_u32(child, "reg", &cs);
346 if (ret)
347 continue;
348 if (cs == index) {
349 /*
350 * SPI children have active low chip selects
351 * by default. This can be specified negatively
352 * by just omitting "spi-cs-high" in the
353 * device node, or actively by tagging on
354 * GPIO_ACTIVE_LOW as flag in the device
355 * tree. If the line is simultaneously
356 * tagged as active low in the device tree
357 * and has the "spi-cs-high" set, we get a
358 * conflict and the "spi-cs-high" flag will
359 * take precedence.
360 */
361 bool active_high = of_property_read_bool(child,
362 "spi-cs-high");
363 of_gpio_quirk_polarity(child, active_high,
364 flags);
365 break;
366 }
367 }
368 }
369
370 /* Legacy handling of stmmac's active-low PHY reset line */
371 if (IS_ENABLED(CONFIG_STMMAC_ETH) &&
372 !strcmp(propname, "snps,reset-gpio") &&
373 of_property_read_bool(np, "snps,reset-active-low"))
374 *flags |= OF_GPIO_ACTIVE_LOW;
375 }
376
377 /**
378 * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API
379 * @np: device node to get GPIO from
380 * @propname: property name containing gpio specifier(s)
381 * @index: index of the GPIO
382 * @flags: a flags pointer to fill in
383 *
384 * Returns:
385 * GPIO descriptor to use with Linux GPIO API, or one of the errno
386 * value on the error condition. If @flags is not NULL the function also fills
387 * in flags for the GPIO.
388 */
of_get_named_gpiod_flags(const struct device_node * np,const char * propname,int index,enum of_gpio_flags * flags)389 static struct gpio_desc *of_get_named_gpiod_flags(const struct device_node *np,
390 const char *propname, int index, enum of_gpio_flags *flags)
391 {
392 struct of_phandle_args gpiospec;
393 struct gpio_desc *desc;
394 int ret;
395
396 ret = of_parse_phandle_with_args_map(np, propname, "gpio", index,
397 &gpiospec);
398 if (ret) {
399 pr_debug("%s: can't parse '%s' property of node '%pOF[%d]'\n",
400 __func__, propname, np, index);
401 return ERR_PTR(ret);
402 }
403
404 struct gpio_device *gdev __free(gpio_device_put) =
405 of_find_gpio_device_by_xlate(&gpiospec);
406 if (!gdev) {
407 desc = ERR_PTR(-EPROBE_DEFER);
408 goto out;
409 }
410
411 desc = of_xlate_and_get_gpiod_flags(gpio_device_get_chip(gdev),
412 &gpiospec, flags);
413 if (IS_ERR(desc))
414 goto out;
415
416 if (flags)
417 of_gpio_flags_quirks(np, propname, flags, index);
418
419 pr_debug("%s: parsed '%s' property of node '%pOF[%d]' - status (%d)\n",
420 __func__, propname, np, index,
421 PTR_ERR_OR_ZERO(desc));
422
423 out:
424 of_node_put(gpiospec.np);
425
426 return desc;
427 }
428
429 /**
430 * of_get_named_gpio() - Get a GPIO number to use with GPIO API
431 * @np: device node to get GPIO from
432 * @propname: Name of property containing gpio specifier(s)
433 * @index: index of the GPIO
434 *
435 * **DEPRECATED** This function is deprecated and must not be used in new code.
436 *
437 * Returns:
438 * GPIO number to use with Linux generic GPIO API, or one of the errno
439 * value on the error condition.
440 */
of_get_named_gpio(const struct device_node * np,const char * propname,int index)441 int of_get_named_gpio(const struct device_node *np, const char *propname,
442 int index)
443 {
444 struct gpio_desc *desc;
445
446 desc = of_get_named_gpiod_flags(np, propname, index, NULL);
447
448 if (IS_ERR(desc))
449 return PTR_ERR(desc);
450 else
451 return desc_to_gpio(desc);
452 }
453 EXPORT_SYMBOL_GPL(of_get_named_gpio);
454
455 /* Converts gpio_lookup_flags into bitmask of GPIO_* values */
of_convert_gpio_flags(enum of_gpio_flags flags)456 static unsigned long of_convert_gpio_flags(enum of_gpio_flags flags)
457 {
458 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
459
460 if (flags & OF_GPIO_ACTIVE_LOW)
461 lflags |= GPIO_ACTIVE_LOW;
462
463 if (flags & OF_GPIO_SINGLE_ENDED) {
464 if (flags & OF_GPIO_OPEN_DRAIN)
465 lflags |= GPIO_OPEN_DRAIN;
466 else
467 lflags |= GPIO_OPEN_SOURCE;
468 }
469
470 if (flags & OF_GPIO_TRANSITORY)
471 lflags |= GPIO_TRANSITORY;
472
473 if (flags & OF_GPIO_PULL_UP)
474 lflags |= GPIO_PULL_UP;
475
476 if (flags & OF_GPIO_PULL_DOWN)
477 lflags |= GPIO_PULL_DOWN;
478
479 if (flags & OF_GPIO_PULL_DISABLE)
480 lflags |= GPIO_PULL_DISABLE;
481
482 return lflags;
483 }
484
of_find_gpio_rename(struct device_node * np,const char * con_id,unsigned int idx,enum of_gpio_flags * of_flags)485 static struct gpio_desc *of_find_gpio_rename(struct device_node *np,
486 const char *con_id,
487 unsigned int idx,
488 enum of_gpio_flags *of_flags)
489 {
490 static const struct of_rename_gpio {
491 const char *con_id;
492 const char *legacy_id; /* NULL - same as con_id */
493 /*
494 * Compatible string can be set to NULL in case where
495 * matching to a particular compatible is not practical,
496 * but it should only be done for gpio names that have
497 * vendor prefix to reduce risk of false positives.
498 * Addition of such entries is strongly discouraged.
499 */
500 const char *compatible;
501 } gpios[] = {
502 #if IS_ENABLED(CONFIG_LCD_HX8357)
503 /* Himax LCD controllers used "gpios-reset" */
504 { "reset", "gpios-reset", "himax,hx8357" },
505 { "reset", "gpios-reset", "himax,hx8369" },
506 #endif
507 #if IS_ENABLED(CONFIG_MFD_ARIZONA)
508 { "wlf,reset", NULL, NULL },
509 #endif
510 #if IS_ENABLED(CONFIG_RTC_DRV_MOXART)
511 { "rtc-data", "gpio-rtc-data", "moxa,moxart-rtc" },
512 { "rtc-sclk", "gpio-rtc-sclk", "moxa,moxart-rtc" },
513 { "rtc-reset", "gpio-rtc-reset", "moxa,moxart-rtc" },
514 #endif
515 #if IS_ENABLED(CONFIG_NFC_MRVL_I2C)
516 { "reset", "reset-n-io", "marvell,nfc-i2c" },
517 #endif
518 #if IS_ENABLED(CONFIG_NFC_MRVL_SPI)
519 { "reset", "reset-n-io", "marvell,nfc-spi" },
520 #endif
521 #if IS_ENABLED(CONFIG_NFC_MRVL_UART)
522 { "reset", "reset-n-io", "marvell,nfc-uart" },
523 { "reset", "reset-n-io", "mrvl,nfc-uart" },
524 #endif
525 #if IS_ENABLED(CONFIG_PCI_LANTIQ)
526 /* MIPS Lantiq PCI */
527 { "reset", "gpio-reset", "lantiq,pci-xway" },
528 #endif
529
530 /*
531 * Some regulator bindings happened before we managed to
532 * establish that GPIO properties should be named
533 * "foo-gpios" so we have this special kludge for them.
534 */
535 #if IS_ENABLED(CONFIG_REGULATOR_ARIZONA_LDO1)
536 { "wlf,ldoena", NULL, NULL }, /* Arizona */
537 #endif
538 #if IS_ENABLED(CONFIG_REGULATOR_WM8994)
539 { "wlf,ldo1ena", NULL, NULL }, /* WM8994 */
540 { "wlf,ldo2ena", NULL, NULL }, /* WM8994 */
541 #endif
542
543 #if IS_ENABLED(CONFIG_SND_SOC_CS42L56)
544 { "reset", "cirrus,gpio-nreset", "cirrus,cs42l56" },
545 #endif
546 #if IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448)
547 { "i2s1-in-sel-gpio1", NULL, "mediatek,mt2701-cs42448-machine" },
548 { "i2s1-in-sel-gpio2", NULL, "mediatek,mt2701-cs42448-machine" },
549 #endif
550 #if IS_ENABLED(CONFIG_SND_SOC_TLV320AIC3X)
551 { "reset", "gpio-reset", "ti,tlv320aic3x" },
552 { "reset", "gpio-reset", "ti,tlv320aic33" },
553 { "reset", "gpio-reset", "ti,tlv320aic3007" },
554 { "reset", "gpio-reset", "ti,tlv320aic3104" },
555 { "reset", "gpio-reset", "ti,tlv320aic3106" },
556 #endif
557 #if IS_ENABLED(CONFIG_SPI_GPIO)
558 /*
559 * The SPI GPIO bindings happened before we managed to
560 * establish that GPIO properties should be named
561 * "foo-gpios" so we have this special kludge for them.
562 */
563 { "miso", "gpio-miso", "spi-gpio" },
564 { "mosi", "gpio-mosi", "spi-gpio" },
565 { "sck", "gpio-sck", "spi-gpio" },
566 #endif
567
568 /*
569 * The old Freescale bindings use simply "gpios" as name
570 * for the chip select lines rather than "cs-gpios" like
571 * all other SPI hardware. Allow this specifically for
572 * Freescale and PPC devices.
573 */
574 #if IS_ENABLED(CONFIG_SPI_FSL_SPI)
575 { "cs", "gpios", "fsl,spi" },
576 { "cs", "gpios", "aeroflexgaisler,spictrl" },
577 #endif
578 #if IS_ENABLED(CONFIG_SPI_PPC4xx)
579 { "cs", "gpios", "ibm,ppc4xx-spi" },
580 #endif
581
582 #if IS_ENABLED(CONFIG_TYPEC_FUSB302)
583 /*
584 * Fairchild FUSB302 host is using undocumented "fcs,int_n"
585 * property without the compulsory "-gpios" suffix.
586 */
587 { "fcs,int_n", NULL, "fcs,fusb302" },
588 #endif
589 };
590 struct gpio_desc *desc;
591 const char *legacy_id;
592 unsigned int i;
593
594 if (!con_id)
595 return ERR_PTR(-ENOENT);
596
597 for (i = 0; i < ARRAY_SIZE(gpios); i++) {
598 if (strcmp(con_id, gpios[i].con_id))
599 continue;
600
601 if (gpios[i].compatible &&
602 !of_device_is_compatible(np, gpios[i].compatible))
603 continue;
604
605 legacy_id = gpios[i].legacy_id ?: gpios[i].con_id;
606 desc = of_get_named_gpiod_flags(np, legacy_id, idx, of_flags);
607 if (!gpiod_not_found(desc)) {
608 pr_info("%s uses legacy gpio name '%s' instead of '%s-gpios'\n",
609 of_node_full_name(np), legacy_id, con_id);
610 return desc;
611 }
612 }
613
614 return ERR_PTR(-ENOENT);
615 }
616
of_find_mt2701_gpio(struct device_node * np,const char * con_id,unsigned int idx,enum of_gpio_flags * of_flags)617 static struct gpio_desc *of_find_mt2701_gpio(struct device_node *np,
618 const char *con_id,
619 unsigned int idx,
620 enum of_gpio_flags *of_flags)
621 {
622 struct gpio_desc *desc;
623 const char *legacy_id;
624
625 if (!IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448))
626 return ERR_PTR(-ENOENT);
627
628 if (!of_device_is_compatible(np, "mediatek,mt2701-cs42448-machine"))
629 return ERR_PTR(-ENOENT);
630
631 if (!con_id || strcmp(con_id, "i2s1-in-sel"))
632 return ERR_PTR(-ENOENT);
633
634 if (idx == 0)
635 legacy_id = "i2s1-in-sel-gpio1";
636 else if (idx == 1)
637 legacy_id = "i2s1-in-sel-gpio2";
638 else
639 return ERR_PTR(-ENOENT);
640
641 desc = of_get_named_gpiod_flags(np, legacy_id, 0, of_flags);
642 if (!gpiod_not_found(desc))
643 pr_info("%s is using legacy gpio name '%s' instead of '%s-gpios'\n",
644 of_node_full_name(np), legacy_id, con_id);
645
646 return desc;
647 }
648
649 /*
650 * Trigger sources are special, they allow us to use any GPIO as a LED trigger
651 * and have the name "trigger-sources" no matter which kind of phandle it is
652 * pointing to, whether to a GPIO, a USB host, a network PHY etc. So in this case
653 * we allow looking something up that is not named "foo-gpios".
654 */
of_find_trigger_gpio(struct device_node * np,const char * con_id,unsigned int idx,enum of_gpio_flags * of_flags)655 static struct gpio_desc *of_find_trigger_gpio(struct device_node *np,
656 const char *con_id,
657 unsigned int idx,
658 enum of_gpio_flags *of_flags)
659 {
660 struct gpio_desc *desc;
661
662 if (!IS_ENABLED(CONFIG_LEDS_TRIGGER_GPIO))
663 return ERR_PTR(-ENOENT);
664
665 if (!con_id || strcmp(con_id, "trigger-sources"))
666 return ERR_PTR(-ENOENT);
667
668 desc = of_get_named_gpiod_flags(np, con_id, idx, of_flags);
669 if (!gpiod_not_found(desc))
670 pr_debug("%s is used as a trigger\n", of_node_full_name(np));
671
672 return desc;
673 }
674
675
676 typedef struct gpio_desc *(*of_find_gpio_quirk)(struct device_node *np,
677 const char *con_id,
678 unsigned int idx,
679 enum of_gpio_flags *of_flags);
680 static const of_find_gpio_quirk of_find_gpio_quirks[] = {
681 of_find_gpio_rename,
682 of_find_mt2701_gpio,
683 of_find_trigger_gpio,
684 NULL
685 };
686
of_find_gpio(struct device_node * np,const char * con_id,unsigned int idx,unsigned long * flags)687 struct gpio_desc *of_find_gpio(struct device_node *np, const char *con_id,
688 unsigned int idx, unsigned long *flags)
689 {
690 char propname[32]; /* 32 is max size of property name */
691 enum of_gpio_flags of_flags;
692 const of_find_gpio_quirk *q;
693 struct gpio_desc *desc;
694
695 /* Try GPIO property "foo-gpios" and "foo-gpio" */
696 for_each_gpio_property_name(propname, con_id) {
697 desc = of_get_named_gpiod_flags(np, propname, idx, &of_flags);
698 if (!gpiod_not_found(desc))
699 break;
700 }
701
702 /* Properly named GPIO was not found, try workarounds */
703 for (q = of_find_gpio_quirks; gpiod_not_found(desc) && *q; q++)
704 desc = (*q)(np, con_id, idx, &of_flags);
705
706 if (IS_ERR(desc))
707 return desc;
708
709 *flags = of_convert_gpio_flags(of_flags);
710
711 return desc;
712 }
713
714 /**
715 * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API
716 * @np: device node to get GPIO from
717 * @chip: GPIO chip whose hog is parsed
718 * @idx: Index of the GPIO to parse
719 * @name: GPIO line name
720 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
721 * of_find_gpio() or of_parse_own_gpio()
722 * @dflags: gpiod_flags - optional GPIO initialization flags
723 *
724 * Returns:
725 * GPIO descriptor to use with Linux GPIO API, or one of the errno
726 * value on the error condition.
727 */
of_parse_own_gpio(struct device_node * np,struct gpio_chip * chip,unsigned int idx,const char ** name,unsigned long * lflags,enum gpiod_flags * dflags)728 static struct gpio_desc *of_parse_own_gpio(struct device_node *np,
729 struct gpio_chip *chip,
730 unsigned int idx, const char **name,
731 unsigned long *lflags,
732 enum gpiod_flags *dflags)
733 {
734 struct device_node *chip_np;
735 enum of_gpio_flags xlate_flags;
736 struct of_phandle_args gpiospec;
737 struct gpio_desc *desc;
738 unsigned int i;
739 u32 tmp;
740 int ret;
741
742 chip_np = dev_of_node(&chip->gpiodev->dev);
743 if (!chip_np)
744 return ERR_PTR(-EINVAL);
745
746 xlate_flags = 0;
747 *lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
748 *dflags = GPIOD_ASIS;
749
750 ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp);
751 if (ret)
752 return ERR_PTR(ret);
753
754 gpiospec.np = chip_np;
755 gpiospec.args_count = tmp;
756
757 for (i = 0; i < tmp; i++) {
758 ret = of_property_read_u32_index(np, "gpios", idx * tmp + i,
759 &gpiospec.args[i]);
760 if (ret)
761 return ERR_PTR(ret);
762 }
763
764 desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, &xlate_flags);
765 if (IS_ERR(desc))
766 return desc;
767
768 *lflags = of_convert_gpio_flags(xlate_flags);
769
770 if (of_property_read_bool(np, "input"))
771 *dflags |= GPIOD_IN;
772 else if (of_property_read_bool(np, "output-low"))
773 *dflags |= GPIOD_OUT_LOW;
774 else if (of_property_read_bool(np, "output-high"))
775 *dflags |= GPIOD_OUT_HIGH;
776 else {
777 pr_warn("GPIO line %d (%pOFn): no hogging state specified, bailing out\n",
778 desc_to_gpio(desc), np);
779 return ERR_PTR(-EINVAL);
780 }
781
782 if (name && of_property_read_string(np, "line-name", name))
783 *name = np->name;
784
785 return desc;
786 }
787
788 /**
789 * of_gpiochip_add_hog - Add all hogs in a hog device node
790 * @chip: gpio chip to act on
791 * @hog: device node describing the hogs
792 *
793 * Returns:
794 * 0 on success, or negative errno on failure.
795 */
of_gpiochip_add_hog(struct gpio_chip * chip,struct device_node * hog)796 static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog)
797 {
798 enum gpiod_flags dflags;
799 struct gpio_desc *desc;
800 unsigned long lflags;
801 const char *name;
802 unsigned int i;
803 int ret;
804
805 for (i = 0;; i++) {
806 desc = of_parse_own_gpio(hog, chip, i, &name, &lflags, &dflags);
807 if (IS_ERR(desc))
808 break;
809
810 ret = gpiod_hog(desc, name, lflags, dflags);
811 if (ret < 0)
812 return ret;
813
814 #ifdef CONFIG_OF_DYNAMIC
815 WRITE_ONCE(desc->hog, hog);
816 #endif
817 }
818
819 return 0;
820 }
821
822 /**
823 * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions
824 * @chip: gpio chip to act on
825 *
826 * This is only used by of_gpiochip_add to request/set GPIO initial
827 * configuration.
828 *
829 * Returns:
830 * 0 on success, or negative errno on failure.
831 */
of_gpiochip_scan_gpios(struct gpio_chip * chip)832 static int of_gpiochip_scan_gpios(struct gpio_chip *chip)
833 {
834 int ret;
835
836 for_each_available_child_of_node_scoped(dev_of_node(&chip->gpiodev->dev), np) {
837 if (!of_property_read_bool(np, "gpio-hog"))
838 continue;
839
840 ret = of_gpiochip_add_hog(chip, np);
841 if (ret < 0)
842 return ret;
843
844 of_node_set_flag(np, OF_POPULATED);
845 }
846
847 return 0;
848 }
849
850 #ifdef CONFIG_OF_DYNAMIC
851 /**
852 * of_gpiochip_remove_hog - Remove all hogs in a hog device node
853 * @chip: gpio chip to act on
854 * @hog: device node describing the hogs
855 */
of_gpiochip_remove_hog(struct gpio_chip * chip,struct device_node * hog)856 static void of_gpiochip_remove_hog(struct gpio_chip *chip,
857 struct device_node *hog)
858 {
859 struct gpio_desc *desc;
860
861 for_each_gpio_desc_with_flag(chip, desc, FLAG_IS_HOGGED)
862 if (READ_ONCE(desc->hog) == hog)
863 gpiochip_free_own_desc(desc);
864 }
865
of_gpiochip_match_node(struct gpio_chip * chip,const void * data)866 static int of_gpiochip_match_node(struct gpio_chip *chip, const void *data)
867 {
868 return device_match_of_node(&chip->gpiodev->dev, data);
869 }
870
of_find_gpio_device_by_node(struct device_node * np)871 static struct gpio_device *of_find_gpio_device_by_node(struct device_node *np)
872 {
873 return gpio_device_find(np, of_gpiochip_match_node);
874 }
875
of_gpio_notify(struct notifier_block * nb,unsigned long action,void * arg)876 static int of_gpio_notify(struct notifier_block *nb, unsigned long action,
877 void *arg)
878 {
879 struct gpio_device *gdev __free(gpio_device_put) = NULL;
880 struct of_reconfig_data *rd = arg;
881 int ret;
882
883 /*
884 * This only supports adding and removing complete gpio-hog nodes.
885 * Modifying an existing gpio-hog node is not supported (except for
886 * changing its "status" property, which is treated the same as
887 * addition/removal).
888 */
889 switch (of_reconfig_get_state_change(action, arg)) {
890 case OF_RECONFIG_CHANGE_ADD:
891 if (!of_property_read_bool(rd->dn, "gpio-hog"))
892 return NOTIFY_DONE; /* not for us */
893
894 if (of_node_test_and_set_flag(rd->dn, OF_POPULATED))
895 return NOTIFY_DONE;
896
897 gdev = of_find_gpio_device_by_node(rd->dn->parent);
898 if (!gdev)
899 return NOTIFY_DONE; /* not for us */
900
901 ret = of_gpiochip_add_hog(gpio_device_get_chip(gdev), rd->dn);
902 if (ret < 0) {
903 pr_err("%s: failed to add hogs for %pOF\n", __func__,
904 rd->dn);
905 of_node_clear_flag(rd->dn, OF_POPULATED);
906 return notifier_from_errno(ret);
907 }
908 return NOTIFY_OK;
909
910 case OF_RECONFIG_CHANGE_REMOVE:
911 if (!of_node_check_flag(rd->dn, OF_POPULATED))
912 return NOTIFY_DONE; /* already depopulated */
913
914 gdev = of_find_gpio_device_by_node(rd->dn->parent);
915 if (!gdev)
916 return NOTIFY_DONE; /* not for us */
917
918 of_gpiochip_remove_hog(gpio_device_get_chip(gdev), rd->dn);
919 of_node_clear_flag(rd->dn, OF_POPULATED);
920 return NOTIFY_OK;
921 }
922
923 return NOTIFY_DONE;
924 }
925
926 struct notifier_block gpio_of_notifier = {
927 .notifier_call = of_gpio_notify,
928 };
929 #endif /* CONFIG_OF_DYNAMIC */
930
931 /**
932 * of_gpio_simple_xlate - translate gpiospec to the GPIO number and flags
933 * @gc: pointer to the gpio_chip structure
934 * @gpiospec: GPIO specifier as found in the device tree
935 * @flags: a flags pointer to fill in
936 *
937 * This is simple translation function, suitable for the most 1:1 mapped
938 * GPIO chips. This function performs only one sanity check: whether GPIO
939 * is less than ngpios (that is specified in the gpio_chip).
940 *
941 * Returns:
942 * GPIO number (>= 0) on success, negative errno on failure.
943 */
of_gpio_simple_xlate(struct gpio_chip * gc,const struct of_phandle_args * gpiospec,u32 * flags)944 static int of_gpio_simple_xlate(struct gpio_chip *gc,
945 const struct of_phandle_args *gpiospec,
946 u32 *flags)
947 {
948 /*
949 * We're discouraging gpio_cells < 2, since that way you'll have to
950 * write your own xlate function (that will have to retrieve the GPIO
951 * number and the flags from a single gpio cell -- this is possible,
952 * but not recommended).
953 */
954 if (gc->of_gpio_n_cells < 2) {
955 WARN_ON(1);
956 return -EINVAL;
957 }
958
959 if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
960 return -EINVAL;
961
962 if (gpiospec->args[0] >= gc->ngpio)
963 return -EINVAL;
964
965 if (flags)
966 *flags = gpiospec->args[1];
967
968 return gpiospec->args[0];
969 }
970
971 #if IS_ENABLED(CONFIG_OF_GPIO_MM_GPIOCHIP)
972 #include <linux/gpio/legacy-of-mm-gpiochip.h>
973 /**
974 * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank)
975 * @np: device node of the GPIO chip
976 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure
977 * @data: driver data to store in the struct gpio_chip
978 *
979 * To use this function you should allocate and fill mm_gc with:
980 *
981 * 1) In the gpio_chip structure:
982 * - all the callbacks
983 * - of_gpio_n_cells
984 * - of_xlate callback (optional)
985 *
986 * 3) In the of_mm_gpio_chip structure:
987 * - save_regs callback (optional)
988 *
989 * If succeeded, this function will map bank's memory and will
990 * do all necessary work for you. Then you'll able to use .regs
991 * to manage GPIOs from the callbacks.
992 *
993 * Returns:
994 * 0 on success, or negative errno on failure.
995 */
of_mm_gpiochip_add_data(struct device_node * np,struct of_mm_gpio_chip * mm_gc,void * data)996 int of_mm_gpiochip_add_data(struct device_node *np,
997 struct of_mm_gpio_chip *mm_gc,
998 void *data)
999 {
1000 int ret = -ENOMEM;
1001 struct gpio_chip *gc = &mm_gc->gc;
1002
1003 gc->label = kasprintf(GFP_KERNEL, "%pOF", np);
1004 if (!gc->label)
1005 goto err0;
1006
1007 mm_gc->regs = of_iomap(np, 0);
1008 if (!mm_gc->regs)
1009 goto err1;
1010
1011 gc->base = -1;
1012
1013 if (mm_gc->save_regs)
1014 mm_gc->save_regs(mm_gc);
1015
1016 fwnode_handle_put(mm_gc->gc.fwnode);
1017 mm_gc->gc.fwnode = fwnode_handle_get(of_fwnode_handle(np));
1018
1019 ret = gpiochip_add_data(gc, data);
1020 if (ret)
1021 goto err2;
1022
1023 return 0;
1024 err2:
1025 of_node_put(np);
1026 iounmap(mm_gc->regs);
1027 err1:
1028 kfree(gc->label);
1029 err0:
1030 pr_err("%pOF: GPIO chip registration failed with status %d\n", np, ret);
1031 return ret;
1032 }
1033 EXPORT_SYMBOL_GPL(of_mm_gpiochip_add_data);
1034
1035 /**
1036 * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank)
1037 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure
1038 */
of_mm_gpiochip_remove(struct of_mm_gpio_chip * mm_gc)1039 void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc)
1040 {
1041 struct gpio_chip *gc = &mm_gc->gc;
1042
1043 gpiochip_remove(gc);
1044 iounmap(mm_gc->regs);
1045 kfree(gc->label);
1046 }
1047 EXPORT_SYMBOL_GPL(of_mm_gpiochip_remove);
1048 #endif
1049
1050 #ifdef CONFIG_PINCTRL
of_gpiochip_add_pin_range(struct gpio_chip * chip)1051 static int of_gpiochip_add_pin_range(struct gpio_chip *chip)
1052 {
1053 struct of_phandle_args pinspec;
1054 struct pinctrl_dev *pctldev;
1055 struct device_node *np;
1056 int index = 0, ret, trim;
1057 const char *name;
1058 static const char group_names_propname[] = "gpio-ranges-group-names";
1059 bool has_group_names;
1060
1061 np = dev_of_node(&chip->gpiodev->dev);
1062 if (!np)
1063 return 0;
1064
1065 has_group_names = of_property_present(np, group_names_propname);
1066
1067 for (;; index++) {
1068 ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3,
1069 index, &pinspec);
1070 if (ret)
1071 break;
1072
1073 pctldev = of_pinctrl_get(pinspec.np);
1074 of_node_put(pinspec.np);
1075 if (!pctldev)
1076 return -EPROBE_DEFER;
1077
1078 /* Ignore ranges outside of this GPIO chip */
1079 if (pinspec.args[0] >= (chip->offset + chip->ngpio))
1080 continue;
1081 if (pinspec.args[0] + pinspec.args[2] <= chip->offset)
1082 continue;
1083
1084 if (pinspec.args[2]) {
1085 /* npins != 0: linear range */
1086 if (has_group_names) {
1087 of_property_read_string_index(np,
1088 group_names_propname,
1089 index, &name);
1090 if (strlen(name)) {
1091 pr_err("%pOF: Group name of numeric GPIO ranges must be the empty string.\n",
1092 np);
1093 break;
1094 }
1095 }
1096
1097 /* Trim the range to fit this GPIO chip */
1098 if (chip->offset > pinspec.args[0]) {
1099 trim = chip->offset - pinspec.args[0];
1100 pinspec.args[2] -= trim;
1101 pinspec.args[1] += trim;
1102 pinspec.args[0] = 0;
1103 } else {
1104 pinspec.args[0] -= chip->offset;
1105 }
1106 if ((pinspec.args[0] + pinspec.args[2]) > chip->ngpio)
1107 pinspec.args[2] = chip->ngpio - pinspec.args[0];
1108
1109 ret = gpiochip_add_pin_range(chip,
1110 pinctrl_dev_get_devname(pctldev),
1111 pinspec.args[0],
1112 pinspec.args[1],
1113 pinspec.args[2]);
1114 if (ret)
1115 return ret;
1116 } else {
1117 /* npins == 0: special range */
1118 if (pinspec.args[1]) {
1119 pr_err("%pOF: Illegal gpio-range format.\n",
1120 np);
1121 break;
1122 }
1123
1124 if (!has_group_names) {
1125 pr_err("%pOF: GPIO group range requested but no %s property.\n",
1126 np, group_names_propname);
1127 break;
1128 }
1129
1130 ret = of_property_read_string_index(np,
1131 group_names_propname,
1132 index, &name);
1133 if (ret)
1134 break;
1135
1136 if (!strlen(name)) {
1137 pr_err("%pOF: Group name of GPIO group range cannot be the empty string.\n",
1138 np);
1139 break;
1140 }
1141
1142 ret = gpiochip_add_pingroup_range(chip, pctldev,
1143 pinspec.args[0], name);
1144 if (ret)
1145 return ret;
1146 }
1147 }
1148
1149 return 0;
1150 }
1151
1152 #else
of_gpiochip_add_pin_range(struct gpio_chip * chip)1153 static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; }
1154 #endif
1155
of_gpiochip_add(struct gpio_chip * chip)1156 int of_gpiochip_add(struct gpio_chip *chip)
1157 {
1158 struct device_node *np;
1159 int ret;
1160
1161 np = dev_of_node(&chip->gpiodev->dev);
1162 if (!np)
1163 return 0;
1164
1165 if (!chip->of_xlate) {
1166 chip->of_gpio_n_cells = 2;
1167 chip->of_xlate = of_gpio_simple_xlate;
1168 }
1169
1170 if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS)
1171 return -EINVAL;
1172
1173 ret = of_gpiochip_add_pin_range(chip);
1174 if (ret)
1175 return ret;
1176
1177 of_node_get(np);
1178
1179 ret = of_gpiochip_scan_gpios(chip);
1180 if (ret)
1181 of_node_put(np);
1182
1183 return ret;
1184 }
1185
of_gpiochip_remove(struct gpio_chip * chip)1186 void of_gpiochip_remove(struct gpio_chip *chip)
1187 {
1188 of_node_put(dev_of_node(&chip->gpiodev->dev));
1189 }
1190