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 #endif
197 #if IS_ENABLED(CONFIG_MTD_NAND_JZ4780)
198 /*
199 * The rb-gpios semantics was undocumented and qi,lb60 (along with
200 * the ingenic driver) got it wrong. The active state encodes the
201 * NAND ready state, which is high level. Since there's no signal
202 * inverter on this board, it should be active-high. Let's fix that
203 * here for older DTs so we can re-use the generic nand_gpio_waitrdy()
204 * helper, and be consistent with what other drivers do.
205 */
206 { "qi,lb60", "rb-gpios", true },
207 #endif
208 #if IS_ENABLED(CONFIG_IEEE802154_CA8210)
209 /*
210 * According to the datasheet, the NRST pin 27 is an active-low
211 * signal. However, the device tree schema and admittedly
212 * the out-of-tree implementations have been used for a long
213 * time incorrectly by describing reset GPIO as active-high.
214 */
215 { "cascoda,ca8210", "reset-gpio", false },
216 #endif
217 #if IS_ENABLED(CONFIG_PCI_LANTIQ)
218 /*
219 * According to the PCI specification, the RST# pin is an
220 * active-low signal. However, most of the device trees that
221 * have been widely used for a long time incorrectly describe
222 * reset GPIO as active-high, and were also using wrong name
223 * for the property.
224 */
225 { "lantiq,pci-xway", "gpio-reset", false },
226 #endif
227 #if IS_ENABLED(CONFIG_TOUCHSCREEN_TSC2005)
228 /*
229 * DTS for Nokia N900 incorrectly specified "active high"
230 * polarity for the reset line, while the chip actually
231 * treats it as "active low".
232 */
233 { "ti,tsc2005", "reset-gpios", false },
234 #endif
235 };
236 unsigned int i;
237
238 for (i = 0; i < ARRAY_SIZE(gpios); i++) {
239 if (of_device_is_compatible(np, gpios[i].compatible) &&
240 !strcmp(propname, gpios[i].propname)) {
241 of_gpio_quirk_polarity(np, gpios[i].active_high, flags);
242 break;
243 }
244 }
245 }
246
of_gpio_set_polarity_by_property(const struct device_node * np,const char * propname,enum of_gpio_flags * flags)247 static void of_gpio_set_polarity_by_property(const struct device_node *np,
248 const char *propname,
249 enum of_gpio_flags *flags)
250 {
251 const struct device_node *np_compat = np;
252 const struct device_node *np_propname = np;
253 static const struct {
254 const char *compatible;
255 const char *gpio_propname;
256 const char *polarity_propname;
257 } gpios[] = {
258 #if IS_ENABLED(CONFIG_FEC)
259 /* Freescale Fast Ethernet Controller */
260 { "fsl,imx25-fec", "phy-reset-gpios", "phy-reset-active-high" },
261 { "fsl,imx27-fec", "phy-reset-gpios", "phy-reset-active-high" },
262 { "fsl,imx28-fec", "phy-reset-gpios", "phy-reset-active-high" },
263 { "fsl,imx6q-fec", "phy-reset-gpios", "phy-reset-active-high" },
264 { "fsl,mvf600-fec", "phy-reset-gpios", "phy-reset-active-high" },
265 { "fsl,imx6sx-fec", "phy-reset-gpios", "phy-reset-active-high" },
266 { "fsl,imx6ul-fec", "phy-reset-gpios", "phy-reset-active-high" },
267 { "fsl,imx8mq-fec", "phy-reset-gpios", "phy-reset-active-high" },
268 { "fsl,imx8qm-fec", "phy-reset-gpios", "phy-reset-active-high" },
269 { "fsl,s32v234-fec", "phy-reset-gpios", "phy-reset-active-high" },
270 #endif
271 #if IS_ENABLED(CONFIG_MMC_ATMELMCI)
272 { "atmel,hsmci", "cd-gpios", "cd-inverted" },
273 #endif
274 #if IS_ENABLED(CONFIG_PCI_IMX6)
275 { "fsl,imx6q-pcie", "reset-gpio", "reset-gpio-active-high" },
276 { "fsl,imx6sx-pcie", "reset-gpio", "reset-gpio-active-high" },
277 { "fsl,imx6qp-pcie", "reset-gpio", "reset-gpio-active-high" },
278 { "fsl,imx7d-pcie", "reset-gpio", "reset-gpio-active-high" },
279 { "fsl,imx8mq-pcie", "reset-gpio", "reset-gpio-active-high" },
280 { "fsl,imx8mm-pcie", "reset-gpio", "reset-gpio-active-high" },
281 { "fsl,imx8mp-pcie", "reset-gpio", "reset-gpio-active-high" },
282 #endif
283
284 /*
285 * The regulator GPIO handles are specified such that the
286 * presence or absence of "enable-active-high" solely controls
287 * the polarity of the GPIO line. Any phandle flags must
288 * be actively ignored.
289 */
290 #if IS_ENABLED(CONFIG_REGULATOR_FIXED_VOLTAGE)
291 { "regulator-fixed", "gpios", "enable-active-high" },
292 { "regulator-fixed", "gpio", "enable-active-high" },
293 { "reg-fixed-voltage", "gpios", "enable-active-high" },
294 { "reg-fixed-voltage", "gpio", "enable-active-high" },
295 #endif
296 #if IS_ENABLED(CONFIG_REGULATOR_GPIO)
297 { "regulator-gpio", "enable-gpio", "enable-active-high" },
298 { "regulator-gpio", "enable-gpios", "enable-active-high" },
299 #endif
300 };
301 unsigned int i;
302 bool active_high;
303
304 #if IS_ENABLED(CONFIG_MMC_ATMELMCI)
305 /*
306 * The Atmel HSMCI has compatible property in the parent node and
307 * gpio property in a child node
308 */
309 if (of_device_is_compatible(np->parent, "atmel,hsmci")) {
310 np_compat = np->parent;
311 np_propname = np;
312 }
313 #endif
314
315 for (i = 0; i < ARRAY_SIZE(gpios); i++) {
316 if (of_device_is_compatible(np_compat, gpios[i].compatible) &&
317 !strcmp(propname, gpios[i].gpio_propname)) {
318 active_high = of_property_read_bool(np_propname,
319 gpios[i].polarity_propname);
320 of_gpio_quirk_polarity(np, active_high, flags);
321 break;
322 }
323 }
324 }
325
of_gpio_flags_quirks(const struct device_node * np,const char * propname,enum of_gpio_flags * flags,int index)326 static void of_gpio_flags_quirks(const struct device_node *np,
327 const char *propname,
328 enum of_gpio_flags *flags,
329 int index)
330 {
331 of_gpio_try_fixup_polarity(np, propname, flags);
332 of_gpio_set_polarity_by_property(np, propname, flags);
333
334 /*
335 * Legacy open drain handling for fixed voltage regulators.
336 */
337 if (IS_ENABLED(CONFIG_REGULATOR) &&
338 of_device_is_compatible(np, "reg-fixed-voltage") &&
339 of_property_read_bool(np, "gpio-open-drain")) {
340 *flags |= (OF_GPIO_SINGLE_ENDED | OF_GPIO_OPEN_DRAIN);
341 pr_info("%s uses legacy open drain flag - update the DTS if you can\n",
342 of_node_full_name(np));
343 }
344
345 /*
346 * Legacy handling of SPI active high chip select. If we have a
347 * property named "cs-gpios" we need to inspect the child node
348 * to determine if the flags should have inverted semantics.
349 */
350 if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") &&
351 of_property_present(np, "cs-gpios")) {
352 u32 cs;
353 int ret;
354
355 for_each_child_of_node_scoped(np, child) {
356 ret = of_property_read_u32(child, "reg", &cs);
357 if (ret)
358 continue;
359 if (cs == index) {
360 /*
361 * SPI children have active low chip selects
362 * by default. This can be specified negatively
363 * by just omitting "spi-cs-high" in the
364 * device node, or actively by tagging on
365 * GPIO_ACTIVE_LOW as flag in the device
366 * tree. If the line is simultaneously
367 * tagged as active low in the device tree
368 * and has the "spi-cs-high" set, we get a
369 * conflict and the "spi-cs-high" flag will
370 * take precedence.
371 */
372 bool active_high = of_property_read_bool(child,
373 "spi-cs-high");
374 of_gpio_quirk_polarity(child, active_high,
375 flags);
376 break;
377 }
378 }
379 }
380
381 /* Legacy handling of stmmac's active-low PHY reset line */
382 if (IS_ENABLED(CONFIG_STMMAC_ETH) &&
383 !strcmp(propname, "snps,reset-gpio") &&
384 of_property_read_bool(np, "snps,reset-active-low"))
385 *flags |= OF_GPIO_ACTIVE_LOW;
386 }
387
388 /**
389 * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API
390 * @np: device node to get GPIO from
391 * @propname: property name containing gpio specifier(s)
392 * @index: index of the GPIO
393 * @flags: a flags pointer to fill in
394 *
395 * Returns:
396 * GPIO descriptor to use with Linux GPIO API, or one of the errno
397 * value on the error condition. If @flags is not NULL the function also fills
398 * in flags for the GPIO.
399 */
of_get_named_gpiod_flags(const struct device_node * np,const char * propname,int index,enum of_gpio_flags * flags)400 static struct gpio_desc *of_get_named_gpiod_flags(const struct device_node *np,
401 const char *propname, int index, enum of_gpio_flags *flags)
402 {
403 struct of_phandle_args gpiospec;
404 struct gpio_desc *desc;
405 int ret;
406
407 ret = of_parse_phandle_with_args_map(np, propname, "gpio", index,
408 &gpiospec);
409 if (ret) {
410 pr_debug("%s: can't parse '%s' property of node '%pOF[%d]'\n",
411 __func__, propname, np, index);
412 return ERR_PTR(ret);
413 }
414
415 struct gpio_device *gdev __free(gpio_device_put) =
416 of_find_gpio_device_by_xlate(&gpiospec);
417 if (!gdev) {
418 desc = ERR_PTR(-EPROBE_DEFER);
419 goto out;
420 }
421
422 desc = of_xlate_and_get_gpiod_flags(gpio_device_get_chip(gdev),
423 &gpiospec, flags);
424 if (IS_ERR(desc))
425 goto out;
426
427 if (flags)
428 of_gpio_flags_quirks(np, propname, flags, index);
429
430 pr_debug("%s: parsed '%s' property of node '%pOF[%d]' - status (%d)\n",
431 __func__, propname, np, index,
432 PTR_ERR_OR_ZERO(desc));
433
434 out:
435 of_node_put(gpiospec.np);
436
437 return desc;
438 }
439
440 /**
441 * of_get_named_gpio() - Get a GPIO number to use with GPIO API
442 * @np: device node to get GPIO from
443 * @propname: Name of property containing gpio specifier(s)
444 * @index: index of the GPIO
445 *
446 * **DEPRECATED** This function is deprecated and must not be used in new code.
447 *
448 * Returns:
449 * GPIO number to use with Linux generic GPIO API, or one of the errno
450 * value on the error condition.
451 */
of_get_named_gpio(const struct device_node * np,const char * propname,int index)452 int of_get_named_gpio(const struct device_node *np, const char *propname,
453 int index)
454 {
455 struct gpio_desc *desc;
456
457 desc = of_get_named_gpiod_flags(np, propname, index, NULL);
458
459 if (IS_ERR(desc))
460 return PTR_ERR(desc);
461 else
462 return desc_to_gpio(desc);
463 }
464 EXPORT_SYMBOL_GPL(of_get_named_gpio);
465
466 /* Converts gpio_lookup_flags into bitmask of GPIO_* values */
of_convert_gpio_flags(enum of_gpio_flags flags)467 static unsigned long of_convert_gpio_flags(enum of_gpio_flags flags)
468 {
469 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
470
471 if (flags & OF_GPIO_ACTIVE_LOW)
472 lflags |= GPIO_ACTIVE_LOW;
473
474 if (flags & OF_GPIO_SINGLE_ENDED) {
475 if (flags & OF_GPIO_OPEN_DRAIN)
476 lflags |= GPIO_OPEN_DRAIN;
477 else
478 lflags |= GPIO_OPEN_SOURCE;
479 }
480
481 if (flags & OF_GPIO_TRANSITORY)
482 lflags |= GPIO_TRANSITORY;
483
484 if (flags & OF_GPIO_PULL_UP)
485 lflags |= GPIO_PULL_UP;
486
487 if (flags & OF_GPIO_PULL_DOWN)
488 lflags |= GPIO_PULL_DOWN;
489
490 if (flags & OF_GPIO_PULL_DISABLE)
491 lflags |= GPIO_PULL_DISABLE;
492
493 return lflags;
494 }
495
of_find_gpio_rename(struct device_node * np,const char * con_id,unsigned int idx,enum of_gpio_flags * of_flags)496 static struct gpio_desc *of_find_gpio_rename(struct device_node *np,
497 const char *con_id,
498 unsigned int idx,
499 enum of_gpio_flags *of_flags)
500 {
501 static const struct of_rename_gpio {
502 const char *con_id;
503 const char *legacy_id; /* NULL - same as con_id */
504 /*
505 * Compatible string can be set to NULL in case where
506 * matching to a particular compatible is not practical,
507 * but it should only be done for gpio names that have
508 * vendor prefix to reduce risk of false positives.
509 * Addition of such entries is strongly discouraged.
510 */
511 const char *compatible;
512 } gpios[] = {
513 #if IS_ENABLED(CONFIG_LCD_HX8357)
514 /* Himax LCD controllers used "gpios-reset" */
515 { "reset", "gpios-reset", "himax,hx8357" },
516 { "reset", "gpios-reset", "himax,hx8369" },
517 #endif
518 #if IS_ENABLED(CONFIG_MFD_ARIZONA)
519 { "wlf,reset", NULL, NULL },
520 #endif
521 #if IS_ENABLED(CONFIG_RTC_DRV_MOXART)
522 { "rtc-data", "gpio-rtc-data", "moxa,moxart-rtc" },
523 { "rtc-sclk", "gpio-rtc-sclk", "moxa,moxart-rtc" },
524 { "rtc-reset", "gpio-rtc-reset", "moxa,moxart-rtc" },
525 #endif
526 #if IS_ENABLED(CONFIG_NFC_MRVL_I2C)
527 { "reset", "reset-n-io", "marvell,nfc-i2c" },
528 #endif
529 #if IS_ENABLED(CONFIG_NFC_MRVL_SPI)
530 { "reset", "reset-n-io", "marvell,nfc-spi" },
531 #endif
532 #if IS_ENABLED(CONFIG_NFC_MRVL_UART)
533 { "reset", "reset-n-io", "marvell,nfc-uart" },
534 { "reset", "reset-n-io", "mrvl,nfc-uart" },
535 #endif
536 #if IS_ENABLED(CONFIG_PCI_LANTIQ)
537 /* MIPS Lantiq PCI */
538 { "reset", "gpio-reset", "lantiq,pci-xway" },
539 #endif
540
541 /*
542 * Some regulator bindings happened before we managed to
543 * establish that GPIO properties should be named
544 * "foo-gpios" so we have this special kludge for them.
545 */
546 #if IS_ENABLED(CONFIG_REGULATOR_ARIZONA_LDO1)
547 { "wlf,ldoena", NULL, NULL }, /* Arizona */
548 #endif
549 #if IS_ENABLED(CONFIG_REGULATOR_WM8994)
550 { "wlf,ldo1ena", NULL, NULL }, /* WM8994 */
551 { "wlf,ldo2ena", NULL, NULL }, /* WM8994 */
552 #endif
553
554 #if IS_ENABLED(CONFIG_SND_SOC_CS42L56)
555 { "reset", "cirrus,gpio-nreset", "cirrus,cs42l56" },
556 #endif
557 #if IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448)
558 { "i2s1-in-sel-gpio1", NULL, "mediatek,mt2701-cs42448-machine" },
559 { "i2s1-in-sel-gpio2", NULL, "mediatek,mt2701-cs42448-machine" },
560 #endif
561 #if IS_ENABLED(CONFIG_SND_SOC_TLV320AIC3X)
562 { "reset", "gpio-reset", "ti,tlv320aic3x" },
563 { "reset", "gpio-reset", "ti,tlv320aic33" },
564 { "reset", "gpio-reset", "ti,tlv320aic3007" },
565 { "reset", "gpio-reset", "ti,tlv320aic3104" },
566 { "reset", "gpio-reset", "ti,tlv320aic3106" },
567 #endif
568 #if IS_ENABLED(CONFIG_SPI_GPIO)
569 /*
570 * The SPI GPIO bindings happened before we managed to
571 * establish that GPIO properties should be named
572 * "foo-gpios" so we have this special kludge for them.
573 */
574 { "miso", "gpio-miso", "spi-gpio" },
575 { "mosi", "gpio-mosi", "spi-gpio" },
576 { "sck", "gpio-sck", "spi-gpio" },
577 #endif
578
579 /*
580 * The old Freescale bindings use simply "gpios" as name
581 * for the chip select lines rather than "cs-gpios" like
582 * all other SPI hardware. Allow this specifically for
583 * Freescale and PPC devices.
584 */
585 #if IS_ENABLED(CONFIG_SPI_FSL_SPI)
586 { "cs", "gpios", "fsl,spi" },
587 { "cs", "gpios", "aeroflexgaisler,spictrl" },
588 #endif
589 #if IS_ENABLED(CONFIG_SPI_PPC4xx)
590 { "cs", "gpios", "ibm,ppc4xx-spi" },
591 #endif
592
593 #if IS_ENABLED(CONFIG_TYPEC_FUSB302)
594 /*
595 * Fairchild FUSB302 host is using undocumented "fcs,int_n"
596 * property without the compulsory "-gpios" suffix.
597 */
598 { "fcs,int_n", NULL, "fcs,fusb302" },
599 #endif
600 };
601 struct gpio_desc *desc;
602 const char *legacy_id;
603 unsigned int i;
604
605 if (!con_id)
606 return ERR_PTR(-ENOENT);
607
608 for (i = 0; i < ARRAY_SIZE(gpios); i++) {
609 if (strcmp(con_id, gpios[i].con_id))
610 continue;
611
612 if (gpios[i].compatible &&
613 !of_device_is_compatible(np, gpios[i].compatible))
614 continue;
615
616 legacy_id = gpios[i].legacy_id ?: gpios[i].con_id;
617 desc = of_get_named_gpiod_flags(np, legacy_id, idx, of_flags);
618 if (!gpiod_not_found(desc)) {
619 pr_info("%s uses legacy gpio name '%s' instead of '%s-gpios'\n",
620 of_node_full_name(np), legacy_id, con_id);
621 return desc;
622 }
623 }
624
625 return ERR_PTR(-ENOENT);
626 }
627
of_find_mt2701_gpio(struct device_node * np,const char * con_id,unsigned int idx,enum of_gpio_flags * of_flags)628 static struct gpio_desc *of_find_mt2701_gpio(struct device_node *np,
629 const char *con_id,
630 unsigned int idx,
631 enum of_gpio_flags *of_flags)
632 {
633 struct gpio_desc *desc;
634 const char *legacy_id;
635
636 if (!IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448))
637 return ERR_PTR(-ENOENT);
638
639 if (!of_device_is_compatible(np, "mediatek,mt2701-cs42448-machine"))
640 return ERR_PTR(-ENOENT);
641
642 if (!con_id || strcmp(con_id, "i2s1-in-sel"))
643 return ERR_PTR(-ENOENT);
644
645 if (idx == 0)
646 legacy_id = "i2s1-in-sel-gpio1";
647 else if (idx == 1)
648 legacy_id = "i2s1-in-sel-gpio2";
649 else
650 return ERR_PTR(-ENOENT);
651
652 desc = of_get_named_gpiod_flags(np, legacy_id, 0, of_flags);
653 if (!gpiod_not_found(desc))
654 pr_info("%s is using legacy gpio name '%s' instead of '%s-gpios'\n",
655 of_node_full_name(np), legacy_id, con_id);
656
657 return desc;
658 }
659
660 /*
661 * Trigger sources are special, they allow us to use any GPIO as a LED trigger
662 * and have the name "trigger-sources" no matter which kind of phandle it is
663 * pointing to, whether to a GPIO, a USB host, a network PHY etc. So in this case
664 * we allow looking something up that is not named "foo-gpios".
665 */
of_find_trigger_gpio(struct device_node * np,const char * con_id,unsigned int idx,enum of_gpio_flags * of_flags)666 static struct gpio_desc *of_find_trigger_gpio(struct device_node *np,
667 const char *con_id,
668 unsigned int idx,
669 enum of_gpio_flags *of_flags)
670 {
671 struct gpio_desc *desc;
672
673 if (!IS_ENABLED(CONFIG_LEDS_TRIGGER_GPIO))
674 return ERR_PTR(-ENOENT);
675
676 if (!con_id || strcmp(con_id, "trigger-sources"))
677 return ERR_PTR(-ENOENT);
678
679 desc = of_get_named_gpiod_flags(np, con_id, idx, of_flags);
680 if (!gpiod_not_found(desc))
681 pr_debug("%s is used as a trigger\n", of_node_full_name(np));
682
683 return desc;
684 }
685
686
687 typedef struct gpio_desc *(*of_find_gpio_quirk)(struct device_node *np,
688 const char *con_id,
689 unsigned int idx,
690 enum of_gpio_flags *of_flags);
691 static const of_find_gpio_quirk of_find_gpio_quirks[] = {
692 of_find_gpio_rename,
693 of_find_mt2701_gpio,
694 of_find_trigger_gpio,
695 NULL
696 };
697
of_find_gpio(struct device_node * np,const char * con_id,unsigned int idx,unsigned long * flags)698 struct gpio_desc *of_find_gpio(struct device_node *np, const char *con_id,
699 unsigned int idx, unsigned long *flags)
700 {
701 char propname[32]; /* 32 is max size of property name */
702 enum of_gpio_flags of_flags;
703 const of_find_gpio_quirk *q;
704 struct gpio_desc *desc;
705
706 /* Try GPIO property "foo-gpios" and "foo-gpio" */
707 for_each_gpio_property_name(propname, con_id) {
708 desc = of_get_named_gpiod_flags(np, propname, idx, &of_flags);
709 if (!gpiod_not_found(desc))
710 break;
711 }
712
713 /* Properly named GPIO was not found, try workarounds */
714 for (q = of_find_gpio_quirks; gpiod_not_found(desc) && *q; q++)
715 desc = (*q)(np, con_id, idx, &of_flags);
716
717 if (IS_ERR(desc))
718 return desc;
719
720 *flags = of_convert_gpio_flags(of_flags);
721
722 return desc;
723 }
724
725 /**
726 * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API
727 * @np: device node to get GPIO from
728 * @chip: GPIO chip whose hog is parsed
729 * @idx: Index of the GPIO to parse
730 * @name: GPIO line name
731 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from
732 * of_find_gpio() or of_parse_own_gpio()
733 * @dflags: gpiod_flags - optional GPIO initialization flags
734 *
735 * Returns:
736 * GPIO descriptor to use with Linux GPIO API, or one of the errno
737 * value on the error condition.
738 */
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)739 static struct gpio_desc *of_parse_own_gpio(struct device_node *np,
740 struct gpio_chip *chip,
741 unsigned int idx, const char **name,
742 unsigned long *lflags,
743 enum gpiod_flags *dflags)
744 {
745 struct device_node *chip_np;
746 enum of_gpio_flags xlate_flags;
747 struct of_phandle_args gpiospec;
748 struct gpio_desc *desc;
749 unsigned int i;
750 u32 tmp;
751 int ret;
752
753 chip_np = dev_of_node(&chip->gpiodev->dev);
754 if (!chip_np)
755 return ERR_PTR(-EINVAL);
756
757 xlate_flags = 0;
758 *lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
759 *dflags = GPIOD_ASIS;
760
761 ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp);
762 if (ret)
763 return ERR_PTR(ret);
764
765 gpiospec.np = chip_np;
766 gpiospec.args_count = tmp;
767
768 for (i = 0; i < tmp; i++) {
769 ret = of_property_read_u32_index(np, "gpios", idx * tmp + i,
770 &gpiospec.args[i]);
771 if (ret)
772 return ERR_PTR(ret);
773 }
774
775 desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, &xlate_flags);
776 if (IS_ERR(desc))
777 return desc;
778
779 *lflags = of_convert_gpio_flags(xlate_flags);
780
781 if (of_property_read_bool(np, "input"))
782 *dflags |= GPIOD_IN;
783 else if (of_property_read_bool(np, "output-low"))
784 *dflags |= GPIOD_OUT_LOW;
785 else if (of_property_read_bool(np, "output-high"))
786 *dflags |= GPIOD_OUT_HIGH;
787 else {
788 pr_warn("GPIO line %d (%pOFn): no hogging state specified, bailing out\n",
789 desc_to_gpio(desc), np);
790 return ERR_PTR(-EINVAL);
791 }
792
793 if (name && of_property_read_string(np, "line-name", name))
794 *name = np->name;
795
796 return desc;
797 }
798
799 /**
800 * of_gpiochip_add_hog - Add all hogs in a hog device node
801 * @chip: gpio chip to act on
802 * @hog: device node describing the hogs
803 *
804 * Returns:
805 * 0 on success, or negative errno on failure.
806 */
of_gpiochip_add_hog(struct gpio_chip * chip,struct device_node * hog)807 static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog)
808 {
809 enum gpiod_flags dflags;
810 struct gpio_desc *desc;
811 unsigned long lflags;
812 const char *name;
813 unsigned int i;
814 int ret;
815
816 for (i = 0;; i++) {
817 desc = of_parse_own_gpio(hog, chip, i, &name, &lflags, &dflags);
818 if (IS_ERR(desc))
819 break;
820
821 ret = gpiod_hog(desc, name, lflags, dflags);
822 if (ret < 0)
823 return ret;
824
825 #ifdef CONFIG_OF_DYNAMIC
826 WRITE_ONCE(desc->hog, hog);
827 #endif
828 }
829
830 return 0;
831 }
832
833 /**
834 * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions
835 * @chip: gpio chip to act on
836 *
837 * This is only used by of_gpiochip_add to request/set GPIO initial
838 * configuration.
839 *
840 * Returns:
841 * 0 on success, or negative errno on failure.
842 */
of_gpiochip_scan_gpios(struct gpio_chip * chip)843 static int of_gpiochip_scan_gpios(struct gpio_chip *chip)
844 {
845 int ret;
846
847 for_each_available_child_of_node_scoped(dev_of_node(&chip->gpiodev->dev), np) {
848 if (!of_property_read_bool(np, "gpio-hog"))
849 continue;
850
851 ret = of_gpiochip_add_hog(chip, np);
852 if (ret < 0)
853 return ret;
854
855 of_node_set_flag(np, OF_POPULATED);
856 }
857
858 return 0;
859 }
860
861 #ifdef CONFIG_OF_DYNAMIC
862 /**
863 * of_gpiochip_remove_hog - Remove all hogs in a hog device node
864 * @chip: gpio chip to act on
865 * @hog: device node describing the hogs
866 */
of_gpiochip_remove_hog(struct gpio_chip * chip,struct device_node * hog)867 static void of_gpiochip_remove_hog(struct gpio_chip *chip,
868 struct device_node *hog)
869 {
870 struct gpio_desc *desc;
871
872 for_each_gpio_desc_with_flag(chip, desc, FLAG_IS_HOGGED)
873 if (READ_ONCE(desc->hog) == hog)
874 gpiochip_free_own_desc(desc);
875 }
876
of_gpiochip_match_node(struct gpio_chip * chip,const void * data)877 static int of_gpiochip_match_node(struct gpio_chip *chip, const void *data)
878 {
879 return device_match_of_node(&chip->gpiodev->dev, data);
880 }
881
of_find_gpio_device_by_node(struct device_node * np)882 static struct gpio_device *of_find_gpio_device_by_node(struct device_node *np)
883 {
884 return gpio_device_find(np, of_gpiochip_match_node);
885 }
886
of_gpio_notify(struct notifier_block * nb,unsigned long action,void * arg)887 static int of_gpio_notify(struct notifier_block *nb, unsigned long action,
888 void *arg)
889 {
890 struct gpio_device *gdev __free(gpio_device_put) = NULL;
891 struct of_reconfig_data *rd = arg;
892 int ret;
893
894 /*
895 * This only supports adding and removing complete gpio-hog nodes.
896 * Modifying an existing gpio-hog node is not supported (except for
897 * changing its "status" property, which is treated the same as
898 * addition/removal).
899 */
900 switch (of_reconfig_get_state_change(action, arg)) {
901 case OF_RECONFIG_CHANGE_ADD:
902 if (!of_property_read_bool(rd->dn, "gpio-hog"))
903 return NOTIFY_DONE; /* not for us */
904
905 if (of_node_test_and_set_flag(rd->dn, OF_POPULATED))
906 return NOTIFY_DONE;
907
908 gdev = of_find_gpio_device_by_node(rd->dn->parent);
909 if (!gdev)
910 return NOTIFY_DONE; /* not for us */
911
912 ret = of_gpiochip_add_hog(gpio_device_get_chip(gdev), rd->dn);
913 if (ret < 0) {
914 pr_err("%s: failed to add hogs for %pOF\n", __func__,
915 rd->dn);
916 of_node_clear_flag(rd->dn, OF_POPULATED);
917 return notifier_from_errno(ret);
918 }
919 return NOTIFY_OK;
920
921 case OF_RECONFIG_CHANGE_REMOVE:
922 if (!of_node_check_flag(rd->dn, OF_POPULATED))
923 return NOTIFY_DONE; /* already depopulated */
924
925 gdev = of_find_gpio_device_by_node(rd->dn->parent);
926 if (!gdev)
927 return NOTIFY_DONE; /* not for us */
928
929 of_gpiochip_remove_hog(gpio_device_get_chip(gdev), rd->dn);
930 of_node_clear_flag(rd->dn, OF_POPULATED);
931 return NOTIFY_OK;
932 }
933
934 return NOTIFY_DONE;
935 }
936
937 struct notifier_block gpio_of_notifier = {
938 .notifier_call = of_gpio_notify,
939 };
940 #endif /* CONFIG_OF_DYNAMIC */
941
942 /**
943 * of_gpio_twocell_xlate - translate twocell gpiospec to the GPIO number and flags
944 * @gc: pointer to the gpio_chip structure
945 * @gpiospec: GPIO specifier as found in the device tree
946 * @flags: a flags pointer to fill in
947 *
948 * This is simple translation function, suitable for the most 1:1 mapped
949 * GPIO chips. This function performs only one sanity check: whether GPIO
950 * is less than ngpios (that is specified in the gpio_chip).
951 *
952 * Returns:
953 * GPIO number (>= 0) on success, negative errno on failure.
954 */
of_gpio_twocell_xlate(struct gpio_chip * gc,const struct of_phandle_args * gpiospec,u32 * flags)955 static int of_gpio_twocell_xlate(struct gpio_chip *gc,
956 const struct of_phandle_args *gpiospec,
957 u32 *flags)
958 {
959 /*
960 * We're discouraging gpio_cells < 2, since that way you'll have to
961 * write your own xlate function (that will have to retrieve the GPIO
962 * number and the flags from a single gpio cell -- this is possible,
963 * but not recommended).
964 */
965 if (gc->of_gpio_n_cells != 2) {
966 WARN_ON(1);
967 return -EINVAL;
968 }
969
970 if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))
971 return -EINVAL;
972
973 if (gpiospec->args[0] >= gc->ngpio)
974 return -EINVAL;
975
976 if (flags)
977 *flags = gpiospec->args[1];
978
979 return gpiospec->args[0];
980 }
981
982 /**
983 * of_gpio_threecell_xlate - translate threecell gpiospec to the GPIO number and flags
984 * @gc: pointer to the gpio_chip structure
985 * @gpiospec: GPIO specifier as found in the device tree
986 * @flags: a flags pointer to fill in
987 *
988 * This is simple translation function, suitable for the most 1:n mapped
989 * GPIO chips, i.e. several GPIO chip instances from one device tree node.
990 * In this case the following binding is implied:
991 *
992 * foo-gpios = <&gpio instance offset flags>;
993 *
994 * Returns:
995 * GPIO number (>= 0) on success, negative errno on failure.
996 */
of_gpio_threecell_xlate(struct gpio_chip * gc,const struct of_phandle_args * gpiospec,u32 * flags)997 static int of_gpio_threecell_xlate(struct gpio_chip *gc,
998 const struct of_phandle_args *gpiospec,
999 u32 *flags)
1000 {
1001 if (gc->of_gpio_n_cells != 3) {
1002 WARN_ON(1);
1003 return -EINVAL;
1004 }
1005
1006 if (WARN_ON(gpiospec->args_count != 3))
1007 return -EINVAL;
1008
1009 /*
1010 * Check chip instance number, the driver responds with true if
1011 * this is the chip we are looking for.
1012 */
1013 if (!gc->of_node_instance_match(gc, gpiospec->args[0]))
1014 return -EINVAL;
1015
1016 if (gpiospec->args[1] >= gc->ngpio)
1017 return -EINVAL;
1018
1019 if (flags)
1020 *flags = gpiospec->args[2];
1021
1022 return gpiospec->args[1];
1023 }
1024
1025 #if IS_ENABLED(CONFIG_OF_GPIO_MM_GPIOCHIP)
1026 #include <linux/gpio/legacy-of-mm-gpiochip.h>
1027 /**
1028 * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank)
1029 * @np: device node of the GPIO chip
1030 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure
1031 * @data: driver data to store in the struct gpio_chip
1032 *
1033 * To use this function you should allocate and fill mm_gc with:
1034 *
1035 * 1) In the gpio_chip structure:
1036 * - all the callbacks
1037 * - of_gpio_n_cells
1038 * - of_xlate callback (optional)
1039 *
1040 * 3) In the of_mm_gpio_chip structure:
1041 * - save_regs callback (optional)
1042 *
1043 * If succeeded, this function will map bank's memory and will
1044 * do all necessary work for you. Then you'll able to use .regs
1045 * to manage GPIOs from the callbacks.
1046 *
1047 * Returns:
1048 * 0 on success, or negative errno on failure.
1049 */
of_mm_gpiochip_add_data(struct device_node * np,struct of_mm_gpio_chip * mm_gc,void * data)1050 int of_mm_gpiochip_add_data(struct device_node *np,
1051 struct of_mm_gpio_chip *mm_gc,
1052 void *data)
1053 {
1054 int ret = -ENOMEM;
1055 struct gpio_chip *gc = &mm_gc->gc;
1056
1057 gc->label = kasprintf(GFP_KERNEL, "%pOF", np);
1058 if (!gc->label)
1059 goto err0;
1060
1061 mm_gc->regs = of_iomap(np, 0);
1062 if (!mm_gc->regs)
1063 goto err1;
1064
1065 gc->base = -1;
1066
1067 if (mm_gc->save_regs)
1068 mm_gc->save_regs(mm_gc);
1069
1070 fwnode_handle_put(mm_gc->gc.fwnode);
1071 mm_gc->gc.fwnode = fwnode_handle_get(of_fwnode_handle(np));
1072
1073 ret = gpiochip_add_data(gc, data);
1074 if (ret)
1075 goto err2;
1076
1077 return 0;
1078 err2:
1079 of_node_put(np);
1080 iounmap(mm_gc->regs);
1081 err1:
1082 kfree(gc->label);
1083 err0:
1084 pr_err("%pOF: GPIO chip registration failed with status %d\n", np, ret);
1085 return ret;
1086 }
1087 EXPORT_SYMBOL_GPL(of_mm_gpiochip_add_data);
1088
1089 /**
1090 * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank)
1091 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure
1092 */
of_mm_gpiochip_remove(struct of_mm_gpio_chip * mm_gc)1093 void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc)
1094 {
1095 struct gpio_chip *gc = &mm_gc->gc;
1096
1097 gpiochip_remove(gc);
1098 iounmap(mm_gc->regs);
1099 kfree(gc->label);
1100 }
1101 EXPORT_SYMBOL_GPL(of_mm_gpiochip_remove);
1102 #endif
1103
1104 #ifdef CONFIG_PINCTRL
of_gpiochip_add_pin_range(struct gpio_chip * chip)1105 static int of_gpiochip_add_pin_range(struct gpio_chip *chip)
1106 {
1107 struct of_phandle_args pinspec;
1108 struct pinctrl_dev *pctldev;
1109 struct device_node *np;
1110 int index = 0, ret, trim;
1111 const char *name;
1112 static const char group_names_propname[] = "gpio-ranges-group-names";
1113 bool has_group_names;
1114 int offset; /* Offset of the first GPIO line on the chip */
1115 int pin; /* Pin base number in the range */
1116 int count; /* Number of pins/GPIO lines to map */
1117
1118 np = dev_of_node(&chip->gpiodev->dev);
1119 if (!np)
1120 return 0;
1121
1122 has_group_names = of_property_present(np, group_names_propname);
1123
1124 for (;; index++) {
1125 /*
1126 * Ordinary phandles contain 2-3 cells:
1127 * gpios = <&gpio [instance] offset flags>;
1128 * Ranges always contain one more cell:
1129 * gpio-ranges <&pinctrl [gpio_instance] gpio_offet pin_offet count>;
1130 * This is why we parse chip->of_gpio_n_cells + 1 cells
1131 */
1132 ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges",
1133 chip->of_gpio_n_cells + 1,
1134 index, &pinspec);
1135 if (ret)
1136 break;
1137
1138 pctldev = of_pinctrl_get(pinspec.np);
1139 of_node_put(pinspec.np);
1140 if (!pctldev)
1141 return -EPROBE_DEFER;
1142
1143 if (chip->of_gpio_n_cells == 3) {
1144 /* First cell is the gpiochip instance number */
1145 offset = pinspec.args[1];
1146 pin = pinspec.args[2];
1147 count = pinspec.args[3];
1148 } else {
1149 offset = pinspec.args[0];
1150 pin = pinspec.args[1];
1151 count = pinspec.args[2];
1152 }
1153
1154 /*
1155 * With multiple GPIO chips per node, check that this chip is the
1156 * right instance.
1157 */
1158 if (chip->of_node_instance_match &&
1159 (chip->of_gpio_n_cells == 3) &&
1160 !chip->of_node_instance_match(chip, pinspec.args[0]))
1161 continue;
1162
1163 /* Ignore ranges outside of this GPIO chip */
1164 if (offset >= (chip->offset + chip->ngpio))
1165 continue;
1166 if (offset + count <= chip->offset)
1167 continue;
1168
1169 if (count) {
1170 /* npins != 0: linear range */
1171 if (has_group_names) {
1172 of_property_read_string_index(np,
1173 group_names_propname,
1174 index, &name);
1175 if (strlen(name)) {
1176 pr_err("%pOF: Group name of numeric GPIO ranges must be the empty string.\n",
1177 np);
1178 break;
1179 }
1180 }
1181
1182 /* Trim the range to fit this GPIO chip */
1183 if (chip->offset > offset) {
1184 trim = chip->offset - offset;
1185 count -= trim;
1186 pin += trim;
1187 offset = 0;
1188 } else {
1189 offset -= chip->offset;
1190 }
1191 if ((offset + count) > chip->ngpio)
1192 count = chip->ngpio - offset;
1193
1194 ret = gpiochip_add_pin_range(chip,
1195 pinctrl_dev_get_devname(pctldev),
1196 offset,
1197 pin,
1198 count);
1199 if (ret)
1200 return ret;
1201 } else {
1202 /* npins == 0: special range */
1203 if (pin) {
1204 pr_err("%pOF: Illegal gpio-range format.\n",
1205 np);
1206 break;
1207 }
1208
1209 if (!has_group_names) {
1210 pr_err("%pOF: GPIO group range requested but no %s property.\n",
1211 np, group_names_propname);
1212 break;
1213 }
1214
1215 ret = of_property_read_string_index(np,
1216 group_names_propname,
1217 index, &name);
1218 if (ret)
1219 break;
1220
1221 if (!strlen(name)) {
1222 pr_err("%pOF: Group name of GPIO group range cannot be the empty string.\n",
1223 np);
1224 break;
1225 }
1226
1227 ret = gpiochip_add_pingroup_range(chip, pctldev,
1228 offset, name);
1229 if (ret)
1230 return ret;
1231 }
1232 }
1233
1234 return 0;
1235 }
1236
1237 #else
of_gpiochip_add_pin_range(struct gpio_chip * chip)1238 static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; }
1239 #endif
1240
of_gpiochip_add(struct gpio_chip * chip)1241 int of_gpiochip_add(struct gpio_chip *chip)
1242 {
1243 struct device_node *np;
1244 int ret;
1245
1246 np = dev_of_node(&chip->gpiodev->dev);
1247 if (!np)
1248 return 0;
1249
1250 if (!chip->of_xlate) {
1251 if (chip->of_gpio_n_cells == 3) {
1252 if (!chip->of_node_instance_match)
1253 return -EINVAL;
1254 chip->of_xlate = of_gpio_threecell_xlate;
1255 } else {
1256 chip->of_gpio_n_cells = 2;
1257 chip->of_xlate = of_gpio_twocell_xlate;
1258 }
1259 }
1260
1261 if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS)
1262 return -EINVAL;
1263
1264 ret = of_gpiochip_add_pin_range(chip);
1265 if (ret)
1266 return ret;
1267
1268 of_node_get(np);
1269
1270 ret = of_gpiochip_scan_gpios(chip);
1271 if (ret)
1272 of_node_put(np);
1273
1274 return ret;
1275 }
1276
of_gpiochip_remove(struct gpio_chip * chip)1277 void of_gpiochip_remove(struct gpio_chip *chip)
1278 {
1279 of_node_put(dev_of_node(&chip->gpiodev->dev));
1280 }
1281