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 that the empty GPIO specifiers count too. Returns either 50 * Number of gpios defined in property, 51 * -EINVAL for an incorrectly formed gpios property, or 52 * -ENOENT for a missing gpios property 53 * 54 * Example: 55 * gpios = <0 56 * &gpio1 1 2 57 * 0 58 * &gpio2 3 4>; 59 * 60 * The above example defines four GPIOs, two of which are not specified. 61 * This function will return '4' 62 */ 63 static int of_gpio_named_count(const struct device_node *np, 64 const char *propname) 65 { 66 return of_count_phandle_with_args(np, propname, "#gpio-cells"); 67 } 68 69 /** 70 * of_gpio_spi_cs_get_count() - special GPIO counting for SPI 71 * @dev: Consuming device 72 * @con_id: Function within the GPIO consumer 73 * 74 * Some elder GPIO controllers need special quirks. Currently we handle 75 * the Freescale and PPC GPIO controller with bindings that doesn't use the 76 * established "cs-gpios" for chip selects but instead rely on 77 * "gpios" for the chip select lines. If we detect this, we redirect 78 * the counting of "cs-gpios" to count "gpios" transparent to the 79 * driver. 80 */ 81 static int of_gpio_spi_cs_get_count(struct device *dev, const char *con_id) 82 { 83 struct device_node *np = dev->of_node; 84 85 if (!IS_ENABLED(CONFIG_SPI_MASTER)) 86 return 0; 87 if (!con_id || strcmp(con_id, "cs")) 88 return 0; 89 if (!of_device_is_compatible(np, "fsl,spi") && 90 !of_device_is_compatible(np, "aeroflexgaisler,spictrl") && 91 !of_device_is_compatible(np, "ibm,ppc4xx-spi")) 92 return 0; 93 return of_gpio_named_count(np, "gpios"); 94 } 95 96 int of_gpio_get_count(struct device *dev, const char *con_id) 97 { 98 int ret; 99 char propname[32]; 100 unsigned int i; 101 102 ret = of_gpio_spi_cs_get_count(dev, con_id); 103 if (ret > 0) 104 return ret; 105 106 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { 107 if (con_id) 108 snprintf(propname, sizeof(propname), "%s-%s", 109 con_id, gpio_suffixes[i]); 110 else 111 snprintf(propname, sizeof(propname), "%s", 112 gpio_suffixes[i]); 113 114 ret = of_gpio_named_count(dev->of_node, propname); 115 if (ret > 0) 116 break; 117 } 118 return ret ? ret : -ENOENT; 119 } 120 121 static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip, void *data) 122 { 123 struct of_phandle_args *gpiospec = data; 124 125 return device_match_of_node(&chip->gpiodev->dev, gpiospec->np) && 126 chip->of_xlate && 127 chip->of_xlate(chip, gpiospec, NULL) >= 0; 128 } 129 130 static struct gpio_device * 131 of_find_gpio_device_by_xlate(struct of_phandle_args *gpiospec) 132 { 133 return gpio_device_find(gpiospec, of_gpiochip_match_node_and_xlate); 134 } 135 136 static struct gpio_desc *of_xlate_and_get_gpiod_flags(struct gpio_chip *chip, 137 struct of_phandle_args *gpiospec, 138 enum of_gpio_flags *flags) 139 { 140 int ret; 141 142 if (chip->of_gpio_n_cells != gpiospec->args_count) 143 return ERR_PTR(-EINVAL); 144 145 ret = chip->of_xlate(chip, gpiospec, flags); 146 if (ret < 0) 147 return ERR_PTR(ret); 148 149 return gpiochip_get_desc(chip, ret); 150 } 151 152 /* 153 * Overrides stated polarity of a gpio line and warns when there is a 154 * discrepancy. 155 */ 156 static void of_gpio_quirk_polarity(const struct device_node *np, 157 bool active_high, 158 enum of_gpio_flags *flags) 159 { 160 if (active_high) { 161 if (*flags & OF_GPIO_ACTIVE_LOW) { 162 pr_warn("%s GPIO handle specifies active low - ignored\n", 163 of_node_full_name(np)); 164 *flags &= ~OF_GPIO_ACTIVE_LOW; 165 } 166 } else { 167 if (!(*flags & OF_GPIO_ACTIVE_LOW)) 168 pr_info("%s enforce active low on GPIO handle\n", 169 of_node_full_name(np)); 170 *flags |= OF_GPIO_ACTIVE_LOW; 171 } 172 } 173 174 /* 175 * This quirk does static polarity overrides in cases where existing 176 * DTS specified incorrect polarity. 177 */ 178 static void of_gpio_try_fixup_polarity(const struct device_node *np, 179 const char *propname, 180 enum of_gpio_flags *flags) 181 { 182 static const struct { 183 const char *compatible; 184 const char *propname; 185 bool active_high; 186 } gpios[] = { 187 #if !IS_ENABLED(CONFIG_LCD_HX8357) 188 /* 189 * Himax LCD controllers used incorrectly named 190 * "gpios-reset" property and also specified wrong 191 * polarity. 192 */ 193 { "himax,hx8357", "gpios-reset", false }, 194 { "himax,hx8369", "gpios-reset", false }, 195 /* 196 * The rb-gpios semantics was undocumented and qi,lb60 (along with 197 * the ingenic driver) got it wrong. The active state encodes the 198 * NAND ready state, which is high level. Since there's no signal 199 * inverter on this board, it should be active-high. Let's fix that 200 * here for older DTs so we can re-use the generic nand_gpio_waitrdy() 201 * helper, and be consistent with what other drivers do. 202 */ 203 { "qi,lb60", "rb-gpios", true }, 204 #endif 205 }; 206 unsigned int i; 207 208 for (i = 0; i < ARRAY_SIZE(gpios); i++) { 209 if (of_device_is_compatible(np, gpios[i].compatible) && 210 !strcmp(propname, gpios[i].propname)) { 211 of_gpio_quirk_polarity(np, gpios[i].active_high, flags); 212 break; 213 } 214 } 215 } 216 217 static void of_gpio_set_polarity_by_property(const struct device_node *np, 218 const char *propname, 219 enum of_gpio_flags *flags) 220 { 221 const struct device_node *np_compat = np; 222 const struct device_node *np_propname = np; 223 static const struct { 224 const char *compatible; 225 const char *gpio_propname; 226 const char *polarity_propname; 227 } gpios[] = { 228 #if IS_ENABLED(CONFIG_FEC) 229 /* Freescale Fast Ethernet Controller */ 230 { "fsl,imx25-fec", "phy-reset-gpios", "phy-reset-active-high" }, 231 { "fsl,imx27-fec", "phy-reset-gpios", "phy-reset-active-high" }, 232 { "fsl,imx28-fec", "phy-reset-gpios", "phy-reset-active-high" }, 233 { "fsl,imx6q-fec", "phy-reset-gpios", "phy-reset-active-high" }, 234 { "fsl,mvf600-fec", "phy-reset-gpios", "phy-reset-active-high" }, 235 { "fsl,imx6sx-fec", "phy-reset-gpios", "phy-reset-active-high" }, 236 { "fsl,imx6ul-fec", "phy-reset-gpios", "phy-reset-active-high" }, 237 { "fsl,imx8mq-fec", "phy-reset-gpios", "phy-reset-active-high" }, 238 { "fsl,imx8qm-fec", "phy-reset-gpios", "phy-reset-active-high" }, 239 { "fsl,s32v234-fec", "phy-reset-gpios", "phy-reset-active-high" }, 240 #endif 241 #if IS_ENABLED(CONFIG_PCI_IMX6) 242 { "fsl,imx6q-pcie", "reset-gpio", "reset-gpio-active-high" }, 243 { "fsl,imx6sx-pcie", "reset-gpio", "reset-gpio-active-high" }, 244 { "fsl,imx6qp-pcie", "reset-gpio", "reset-gpio-active-high" }, 245 { "fsl,imx7d-pcie", "reset-gpio", "reset-gpio-active-high" }, 246 { "fsl,imx8mq-pcie", "reset-gpio", "reset-gpio-active-high" }, 247 { "fsl,imx8mm-pcie", "reset-gpio", "reset-gpio-active-high" }, 248 { "fsl,imx8mp-pcie", "reset-gpio", "reset-gpio-active-high" }, 249 #endif 250 251 /* 252 * The regulator GPIO handles are specified such that the 253 * presence or absence of "enable-active-high" solely controls 254 * the polarity of the GPIO line. Any phandle flags must 255 * be actively ignored. 256 */ 257 #if IS_ENABLED(CONFIG_REGULATOR_FIXED_VOLTAGE) 258 { "regulator-fixed", "gpios", "enable-active-high" }, 259 { "regulator-fixed", "gpio", "enable-active-high" }, 260 { "reg-fixed-voltage", "gpios", "enable-active-high" }, 261 { "reg-fixed-voltage", "gpio", "enable-active-high" }, 262 #endif 263 #if IS_ENABLED(CONFIG_REGULATOR_GPIO) 264 { "regulator-gpio", "enable-gpio", "enable-active-high" }, 265 { "regulator-gpio", "enable-gpios", "enable-active-high" }, 266 #endif 267 #if IS_ENABLED(CONFIG_MMC_ATMELMCI) 268 { "atmel,hsmci", "cd-gpios", "cd-inverted" }, 269 #endif 270 }; 271 unsigned int i; 272 bool active_high; 273 274 #if IS_ENABLED(CONFIG_MMC_ATMELMCI) 275 /* 276 * The Atmel HSMCI has compatible property in the parent node and 277 * gpio property in a child node 278 */ 279 if (of_device_is_compatible(np->parent, "atmel,hsmci")) { 280 np_compat = np->parent; 281 np_propname = np; 282 } 283 #endif 284 285 for (i = 0; i < ARRAY_SIZE(gpios); i++) { 286 if (of_device_is_compatible(np_compat, gpios[i].compatible) && 287 !strcmp(propname, gpios[i].gpio_propname)) { 288 active_high = of_property_read_bool(np_propname, 289 gpios[i].polarity_propname); 290 of_gpio_quirk_polarity(np, active_high, flags); 291 break; 292 } 293 } 294 } 295 296 static void of_gpio_flags_quirks(const struct device_node *np, 297 const char *propname, 298 enum of_gpio_flags *flags, 299 int index) 300 { 301 of_gpio_try_fixup_polarity(np, propname, flags); 302 of_gpio_set_polarity_by_property(np, propname, flags); 303 304 /* 305 * Legacy open drain handling for fixed voltage regulators. 306 */ 307 if (IS_ENABLED(CONFIG_REGULATOR) && 308 of_device_is_compatible(np, "reg-fixed-voltage") && 309 of_property_read_bool(np, "gpio-open-drain")) { 310 *flags |= (OF_GPIO_SINGLE_ENDED | OF_GPIO_OPEN_DRAIN); 311 pr_info("%s uses legacy open drain flag - update the DTS if you can\n", 312 of_node_full_name(np)); 313 } 314 315 /* 316 * Legacy handling of SPI active high chip select. If we have a 317 * property named "cs-gpios" we need to inspect the child node 318 * to determine if the flags should have inverted semantics. 319 */ 320 if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") && 321 of_property_read_bool(np, "cs-gpios")) { 322 struct device_node *child; 323 u32 cs; 324 int ret; 325 326 for_each_child_of_node(np, child) { 327 ret = of_property_read_u32(child, "reg", &cs); 328 if (ret) 329 continue; 330 if (cs == index) { 331 /* 332 * SPI children have active low chip selects 333 * by default. This can be specified negatively 334 * by just omitting "spi-cs-high" in the 335 * device node, or actively by tagging on 336 * GPIO_ACTIVE_LOW as flag in the device 337 * tree. If the line is simultaneously 338 * tagged as active low in the device tree 339 * and has the "spi-cs-high" set, we get a 340 * conflict and the "spi-cs-high" flag will 341 * take precedence. 342 */ 343 bool active_high = of_property_read_bool(child, 344 "spi-cs-high"); 345 of_gpio_quirk_polarity(child, active_high, 346 flags); 347 of_node_put(child); 348 break; 349 } 350 } 351 } 352 353 /* Legacy handling of stmmac's active-low PHY reset line */ 354 if (IS_ENABLED(CONFIG_STMMAC_ETH) && 355 !strcmp(propname, "snps,reset-gpio") && 356 of_property_read_bool(np, "snps,reset-active-low")) 357 *flags |= OF_GPIO_ACTIVE_LOW; 358 } 359 360 /** 361 * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API 362 * @np: device node to get GPIO from 363 * @propname: property name containing gpio specifier(s) 364 * @index: index of the GPIO 365 * @flags: a flags pointer to fill in 366 * 367 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno 368 * value on the error condition. If @flags is not NULL the function also fills 369 * in flags for the GPIO. 370 */ 371 static struct gpio_desc *of_get_named_gpiod_flags(const struct device_node *np, 372 const char *propname, int index, enum of_gpio_flags *flags) 373 { 374 struct of_phandle_args gpiospec; 375 struct gpio_desc *desc; 376 int ret; 377 378 ret = of_parse_phandle_with_args_map(np, propname, "gpio", index, 379 &gpiospec); 380 if (ret) { 381 pr_debug("%s: can't parse '%s' property of node '%pOF[%d]'\n", 382 __func__, propname, np, index); 383 return ERR_PTR(ret); 384 } 385 386 struct gpio_device *gdev __free(gpio_device_put) = 387 of_find_gpio_device_by_xlate(&gpiospec); 388 if (!gdev) { 389 desc = ERR_PTR(-EPROBE_DEFER); 390 goto out; 391 } 392 393 desc = of_xlate_and_get_gpiod_flags(gpio_device_get_chip(gdev), 394 &gpiospec, flags); 395 if (IS_ERR(desc)) 396 goto out; 397 398 if (flags) 399 of_gpio_flags_quirks(np, propname, flags, index); 400 401 pr_debug("%s: parsed '%s' property of node '%pOF[%d]' - status (%d)\n", 402 __func__, propname, np, index, 403 PTR_ERR_OR_ZERO(desc)); 404 405 out: 406 of_node_put(gpiospec.np); 407 408 return desc; 409 } 410 411 /** 412 * of_get_named_gpio() - Get a GPIO number to use with GPIO API 413 * @np: device node to get GPIO from 414 * @propname: Name of property containing gpio specifier(s) 415 * @index: index of the GPIO 416 * 417 * Returns GPIO number to use with Linux generic GPIO API, or one of the errno 418 * value on the error condition. 419 */ 420 int of_get_named_gpio(const struct device_node *np, const char *propname, 421 int index) 422 { 423 struct gpio_desc *desc; 424 425 desc = of_get_named_gpiod_flags(np, propname, index, NULL); 426 427 if (IS_ERR(desc)) 428 return PTR_ERR(desc); 429 else 430 return desc_to_gpio(desc); 431 } 432 EXPORT_SYMBOL_GPL(of_get_named_gpio); 433 434 /* Converts gpio_lookup_flags into bitmask of GPIO_* values */ 435 static unsigned long of_convert_gpio_flags(enum of_gpio_flags flags) 436 { 437 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT; 438 439 if (flags & OF_GPIO_ACTIVE_LOW) 440 lflags |= GPIO_ACTIVE_LOW; 441 442 if (flags & OF_GPIO_SINGLE_ENDED) { 443 if (flags & OF_GPIO_OPEN_DRAIN) 444 lflags |= GPIO_OPEN_DRAIN; 445 else 446 lflags |= GPIO_OPEN_SOURCE; 447 } 448 449 if (flags & OF_GPIO_TRANSITORY) 450 lflags |= GPIO_TRANSITORY; 451 452 if (flags & OF_GPIO_PULL_UP) 453 lflags |= GPIO_PULL_UP; 454 455 if (flags & OF_GPIO_PULL_DOWN) 456 lflags |= GPIO_PULL_DOWN; 457 458 if (flags & OF_GPIO_PULL_DISABLE) 459 lflags |= GPIO_PULL_DISABLE; 460 461 return lflags; 462 } 463 464 static struct gpio_desc *of_find_gpio_rename(struct device_node *np, 465 const char *con_id, 466 unsigned int idx, 467 enum of_gpio_flags *of_flags) 468 { 469 static const struct of_rename_gpio { 470 const char *con_id; 471 const char *legacy_id; /* NULL - same as con_id */ 472 /* 473 * Compatible string can be set to NULL in case where 474 * matching to a particular compatible is not practical, 475 * but it should only be done for gpio names that have 476 * vendor prefix to reduce risk of false positives. 477 * Addition of such entries is strongly discouraged. 478 */ 479 const char *compatible; 480 } gpios[] = { 481 #if !IS_ENABLED(CONFIG_LCD_HX8357) 482 /* Himax LCD controllers used "gpios-reset" */ 483 { "reset", "gpios-reset", "himax,hx8357" }, 484 { "reset", "gpios-reset", "himax,hx8369" }, 485 #endif 486 #if IS_ENABLED(CONFIG_MFD_ARIZONA) 487 { "wlf,reset", NULL, NULL }, 488 #endif 489 #if IS_ENABLED(CONFIG_RTC_DRV_MOXART) 490 { "rtc-data", "gpio-rtc-data", "moxa,moxart-rtc" }, 491 { "rtc-sclk", "gpio-rtc-sclk", "moxa,moxart-rtc" }, 492 { "rtc-reset", "gpio-rtc-reset", "moxa,moxart-rtc" }, 493 #endif 494 #if IS_ENABLED(CONFIG_NFC_MRVL_I2C) 495 { "reset", "reset-n-io", "marvell,nfc-i2c" }, 496 #endif 497 #if IS_ENABLED(CONFIG_NFC_MRVL_SPI) 498 { "reset", "reset-n-io", "marvell,nfc-spi" }, 499 #endif 500 #if IS_ENABLED(CONFIG_NFC_MRVL_UART) 501 { "reset", "reset-n-io", "marvell,nfc-uart" }, 502 { "reset", "reset-n-io", "mrvl,nfc-uart" }, 503 #endif 504 #if !IS_ENABLED(CONFIG_PCI_LANTIQ) 505 /* MIPS Lantiq PCI */ 506 { "reset", "gpios-reset", "lantiq,pci-xway" }, 507 #endif 508 509 /* 510 * Some regulator bindings happened before we managed to 511 * establish that GPIO properties should be named 512 * "foo-gpios" so we have this special kludge for them. 513 */ 514 #if IS_ENABLED(CONFIG_REGULATOR_ARIZONA_LDO1) 515 { "wlf,ldoena", NULL, NULL }, /* Arizona */ 516 #endif 517 #if IS_ENABLED(CONFIG_REGULATOR_WM8994) 518 { "wlf,ldo1ena", NULL, NULL }, /* WM8994 */ 519 { "wlf,ldo2ena", NULL, NULL }, /* WM8994 */ 520 #endif 521 522 #if IS_ENABLED(CONFIG_SND_SOC_CS42L56) 523 { "reset", "cirrus,gpio-nreset", "cirrus,cs42l56" }, 524 #endif 525 #if IS_ENABLED(CONFIG_SND_SOC_TLV320AIC3X) 526 { "reset", "gpio-reset", "ti,tlv320aic3x" }, 527 { "reset", "gpio-reset", "ti,tlv320aic33" }, 528 { "reset", "gpio-reset", "ti,tlv320aic3007" }, 529 { "reset", "gpio-reset", "ti,tlv320aic3104" }, 530 { "reset", "gpio-reset", "ti,tlv320aic3106" }, 531 #endif 532 #if IS_ENABLED(CONFIG_SPI_GPIO) 533 /* 534 * The SPI GPIO bindings happened before we managed to 535 * establish that GPIO properties should be named 536 * "foo-gpios" so we have this special kludge for them. 537 */ 538 { "miso", "gpio-miso", "spi-gpio" }, 539 { "mosi", "gpio-mosi", "spi-gpio" }, 540 { "sck", "gpio-sck", "spi-gpio" }, 541 #endif 542 543 /* 544 * The old Freescale bindings use simply "gpios" as name 545 * for the chip select lines rather than "cs-gpios" like 546 * all other SPI hardware. Allow this specifically for 547 * Freescale and PPC devices. 548 */ 549 #if IS_ENABLED(CONFIG_SPI_FSL_SPI) 550 { "cs", "gpios", "fsl,spi" }, 551 { "cs", "gpios", "aeroflexgaisler,spictrl" }, 552 #endif 553 #if IS_ENABLED(CONFIG_SPI_PPC4xx) 554 { "cs", "gpios", "ibm,ppc4xx-spi" }, 555 #endif 556 557 #if IS_ENABLED(CONFIG_TYPEC_FUSB302) 558 /* 559 * Fairchild FUSB302 host is using undocumented "fcs,int_n" 560 * property without the compulsory "-gpios" suffix. 561 */ 562 { "fcs,int_n", NULL, "fcs,fusb302" }, 563 #endif 564 }; 565 struct gpio_desc *desc; 566 const char *legacy_id; 567 unsigned int i; 568 569 if (!con_id) 570 return ERR_PTR(-ENOENT); 571 572 for (i = 0; i < ARRAY_SIZE(gpios); i++) { 573 if (strcmp(con_id, gpios[i].con_id)) 574 continue; 575 576 if (gpios[i].compatible && 577 !of_device_is_compatible(np, gpios[i].compatible)) 578 continue; 579 580 legacy_id = gpios[i].legacy_id ?: gpios[i].con_id; 581 desc = of_get_named_gpiod_flags(np, legacy_id, idx, of_flags); 582 if (!gpiod_not_found(desc)) { 583 pr_info("%s uses legacy gpio name '%s' instead of '%s-gpios'\n", 584 of_node_full_name(np), legacy_id, con_id); 585 return desc; 586 } 587 } 588 589 return ERR_PTR(-ENOENT); 590 } 591 592 static struct gpio_desc *of_find_mt2701_gpio(struct device_node *np, 593 const char *con_id, 594 unsigned int idx, 595 enum of_gpio_flags *of_flags) 596 { 597 struct gpio_desc *desc; 598 const char *legacy_id; 599 600 if (!IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448)) 601 return ERR_PTR(-ENOENT); 602 603 if (!of_device_is_compatible(np, "mediatek,mt2701-cs42448-machine")) 604 return ERR_PTR(-ENOENT); 605 606 if (!con_id || strcmp(con_id, "i2s1-in-sel")) 607 return ERR_PTR(-ENOENT); 608 609 if (idx == 0) 610 legacy_id = "i2s1-in-sel-gpio1"; 611 else if (idx == 1) 612 legacy_id = "i2s1-in-sel-gpio2"; 613 else 614 return ERR_PTR(-ENOENT); 615 616 desc = of_get_named_gpiod_flags(np, legacy_id, 0, of_flags); 617 if (!gpiod_not_found(desc)) 618 pr_info("%s is using legacy gpio name '%s' instead of '%s-gpios'\n", 619 of_node_full_name(np), legacy_id, con_id); 620 621 return desc; 622 } 623 624 /* 625 * Trigger sources are special, they allow us to use any GPIO as a LED trigger 626 * and have the name "trigger-sources" no matter which kind of phandle it is 627 * pointing to, whether to a GPIO, a USB host, a network PHY etc. So in this case 628 * we allow looking something up that is not named "foo-gpios". 629 */ 630 static struct gpio_desc *of_find_trigger_gpio(struct device_node *np, 631 const char *con_id, 632 unsigned int idx, 633 enum of_gpio_flags *of_flags) 634 { 635 struct gpio_desc *desc; 636 637 if (!IS_ENABLED(CONFIG_LEDS_TRIGGER_GPIO)) 638 return ERR_PTR(-ENOENT); 639 640 if (!con_id || strcmp(con_id, "trigger-sources")) 641 return ERR_PTR(-ENOENT); 642 643 desc = of_get_named_gpiod_flags(np, con_id, idx, of_flags); 644 if (!gpiod_not_found(desc)) 645 pr_debug("%s is used as a trigger\n", of_node_full_name(np)); 646 647 return desc; 648 } 649 650 651 typedef struct gpio_desc *(*of_find_gpio_quirk)(struct device_node *np, 652 const char *con_id, 653 unsigned int idx, 654 enum of_gpio_flags *of_flags); 655 static const of_find_gpio_quirk of_find_gpio_quirks[] = { 656 of_find_gpio_rename, 657 of_find_mt2701_gpio, 658 of_find_trigger_gpio, 659 NULL 660 }; 661 662 struct gpio_desc *of_find_gpio(struct device_node *np, const char *con_id, 663 unsigned int idx, unsigned long *flags) 664 { 665 char prop_name[32]; /* 32 is max size of property name */ 666 enum of_gpio_flags of_flags; 667 const of_find_gpio_quirk *q; 668 struct gpio_desc *desc; 669 unsigned int i; 670 671 /* Try GPIO property "foo-gpios" and "foo-gpio" */ 672 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { 673 if (con_id) 674 snprintf(prop_name, sizeof(prop_name), "%s-%s", con_id, 675 gpio_suffixes[i]); 676 else 677 snprintf(prop_name, sizeof(prop_name), "%s", 678 gpio_suffixes[i]); 679 680 desc = of_get_named_gpiod_flags(np, prop_name, idx, &of_flags); 681 682 if (!gpiod_not_found(desc)) 683 break; 684 } 685 686 /* Properly named GPIO was not found, try workarounds */ 687 for (q = of_find_gpio_quirks; gpiod_not_found(desc) && *q; q++) 688 desc = (*q)(np, con_id, idx, &of_flags); 689 690 if (IS_ERR(desc)) 691 return desc; 692 693 *flags = of_convert_gpio_flags(of_flags); 694 695 return desc; 696 } 697 698 /** 699 * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API 700 * @np: device node to get GPIO from 701 * @chip: GPIO chip whose hog is parsed 702 * @idx: Index of the GPIO to parse 703 * @name: GPIO line name 704 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from 705 * of_find_gpio() or of_parse_own_gpio() 706 * @dflags: gpiod_flags - optional GPIO initialization flags 707 * 708 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno 709 * value on the error condition. 710 */ 711 static struct gpio_desc *of_parse_own_gpio(struct device_node *np, 712 struct gpio_chip *chip, 713 unsigned int idx, const char **name, 714 unsigned long *lflags, 715 enum gpiod_flags *dflags) 716 { 717 struct device_node *chip_np; 718 enum of_gpio_flags xlate_flags; 719 struct of_phandle_args gpiospec; 720 struct gpio_desc *desc; 721 unsigned int i; 722 u32 tmp; 723 int ret; 724 725 chip_np = dev_of_node(&chip->gpiodev->dev); 726 if (!chip_np) 727 return ERR_PTR(-EINVAL); 728 729 xlate_flags = 0; 730 *lflags = GPIO_LOOKUP_FLAGS_DEFAULT; 731 *dflags = GPIOD_ASIS; 732 733 ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp); 734 if (ret) 735 return ERR_PTR(ret); 736 737 gpiospec.np = chip_np; 738 gpiospec.args_count = tmp; 739 740 for (i = 0; i < tmp; i++) { 741 ret = of_property_read_u32_index(np, "gpios", idx * tmp + i, 742 &gpiospec.args[i]); 743 if (ret) 744 return ERR_PTR(ret); 745 } 746 747 desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, &xlate_flags); 748 if (IS_ERR(desc)) 749 return desc; 750 751 *lflags = of_convert_gpio_flags(xlate_flags); 752 753 if (of_property_read_bool(np, "input")) 754 *dflags |= GPIOD_IN; 755 else if (of_property_read_bool(np, "output-low")) 756 *dflags |= GPIOD_OUT_LOW; 757 else if (of_property_read_bool(np, "output-high")) 758 *dflags |= GPIOD_OUT_HIGH; 759 else { 760 pr_warn("GPIO line %d (%pOFn): no hogging state specified, bailing out\n", 761 desc_to_gpio(desc), np); 762 return ERR_PTR(-EINVAL); 763 } 764 765 if (name && of_property_read_string(np, "line-name", name)) 766 *name = np->name; 767 768 return desc; 769 } 770 771 /** 772 * of_gpiochip_add_hog - Add all hogs in a hog device node 773 * @chip: gpio chip to act on 774 * @hog: device node describing the hogs 775 * 776 * Returns error if it fails otherwise 0 on success. 777 */ 778 static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog) 779 { 780 enum gpiod_flags dflags; 781 struct gpio_desc *desc; 782 unsigned long lflags; 783 const char *name; 784 unsigned int i; 785 int ret; 786 787 for (i = 0;; i++) { 788 desc = of_parse_own_gpio(hog, chip, i, &name, &lflags, &dflags); 789 if (IS_ERR(desc)) 790 break; 791 792 ret = gpiod_hog(desc, name, lflags, dflags); 793 if (ret < 0) 794 return ret; 795 796 #ifdef CONFIG_OF_DYNAMIC 797 desc->hog = hog; 798 #endif 799 } 800 801 return 0; 802 } 803 804 /** 805 * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions 806 * @chip: gpio chip to act on 807 * 808 * This is only used by of_gpiochip_add to request/set GPIO initial 809 * configuration. 810 * It returns error if it fails otherwise 0 on success. 811 */ 812 static int of_gpiochip_scan_gpios(struct gpio_chip *chip) 813 { 814 struct device_node *np; 815 int ret; 816 817 for_each_available_child_of_node(dev_of_node(&chip->gpiodev->dev), np) { 818 if (!of_property_read_bool(np, "gpio-hog")) 819 continue; 820 821 ret = of_gpiochip_add_hog(chip, np); 822 if (ret < 0) { 823 of_node_put(np); 824 return ret; 825 } 826 827 of_node_set_flag(np, OF_POPULATED); 828 } 829 830 return 0; 831 } 832 833 #ifdef CONFIG_OF_DYNAMIC 834 /** 835 * of_gpiochip_remove_hog - Remove all hogs in a hog device node 836 * @chip: gpio chip to act on 837 * @hog: device node describing the hogs 838 */ 839 static void of_gpiochip_remove_hog(struct gpio_chip *chip, 840 struct device_node *hog) 841 { 842 struct gpio_desc *desc; 843 844 for_each_gpio_desc_with_flag(chip, desc, FLAG_IS_HOGGED) 845 if (desc->hog == hog) 846 gpiochip_free_own_desc(desc); 847 } 848 849 static int of_gpiochip_match_node(struct gpio_chip *chip, void *data) 850 { 851 return device_match_of_node(&chip->gpiodev->dev, data); 852 } 853 854 static struct gpio_device *of_find_gpio_device_by_node(struct device_node *np) 855 { 856 return gpio_device_find(np, of_gpiochip_match_node); 857 } 858 859 static int of_gpio_notify(struct notifier_block *nb, unsigned long action, 860 void *arg) 861 { 862 struct gpio_device *gdev __free(gpio_device_put) = NULL; 863 struct of_reconfig_data *rd = arg; 864 int ret; 865 866 /* 867 * This only supports adding and removing complete gpio-hog nodes. 868 * Modifying an existing gpio-hog node is not supported (except for 869 * changing its "status" property, which is treated the same as 870 * addition/removal). 871 */ 872 switch (of_reconfig_get_state_change(action, arg)) { 873 case OF_RECONFIG_CHANGE_ADD: 874 if (!of_property_read_bool(rd->dn, "gpio-hog")) 875 return NOTIFY_DONE; /* not for us */ 876 877 if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) 878 return NOTIFY_DONE; 879 880 gdev = of_find_gpio_device_by_node(rd->dn->parent); 881 if (!gdev) 882 return NOTIFY_DONE; /* not for us */ 883 884 ret = of_gpiochip_add_hog(gpio_device_get_chip(gdev), rd->dn); 885 if (ret < 0) { 886 pr_err("%s: failed to add hogs for %pOF\n", __func__, 887 rd->dn); 888 of_node_clear_flag(rd->dn, OF_POPULATED); 889 return notifier_from_errno(ret); 890 } 891 return NOTIFY_OK; 892 893 case OF_RECONFIG_CHANGE_REMOVE: 894 if (!of_node_check_flag(rd->dn, OF_POPULATED)) 895 return NOTIFY_DONE; /* already depopulated */ 896 897 gdev = of_find_gpio_device_by_node(rd->dn->parent); 898 if (!gdev) 899 return NOTIFY_DONE; /* not for us */ 900 901 of_gpiochip_remove_hog(gpio_device_get_chip(gdev), rd->dn); 902 of_node_clear_flag(rd->dn, OF_POPULATED); 903 return NOTIFY_OK; 904 } 905 906 return NOTIFY_DONE; 907 } 908 909 struct notifier_block gpio_of_notifier = { 910 .notifier_call = of_gpio_notify, 911 }; 912 #endif /* CONFIG_OF_DYNAMIC */ 913 914 /** 915 * of_gpio_simple_xlate - translate gpiospec to the GPIO number and flags 916 * @gc: pointer to the gpio_chip structure 917 * @gpiospec: GPIO specifier as found in the device tree 918 * @flags: a flags pointer to fill in 919 * 920 * This is simple translation function, suitable for the most 1:1 mapped 921 * GPIO chips. This function performs only one sanity check: whether GPIO 922 * is less than ngpios (that is specified in the gpio_chip). 923 */ 924 static int of_gpio_simple_xlate(struct gpio_chip *gc, 925 const struct of_phandle_args *gpiospec, 926 u32 *flags) 927 { 928 /* 929 * We're discouraging gpio_cells < 2, since that way you'll have to 930 * write your own xlate function (that will have to retrieve the GPIO 931 * number and the flags from a single gpio cell -- this is possible, 932 * but not recommended). 933 */ 934 if (gc->of_gpio_n_cells < 2) { 935 WARN_ON(1); 936 return -EINVAL; 937 } 938 939 if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells)) 940 return -EINVAL; 941 942 if (gpiospec->args[0] >= gc->ngpio) 943 return -EINVAL; 944 945 if (flags) 946 *flags = gpiospec->args[1]; 947 948 return gpiospec->args[0]; 949 } 950 951 #if IS_ENABLED(CONFIG_OF_GPIO_MM_GPIOCHIP) 952 #include <linux/gpio/legacy-of-mm-gpiochip.h> 953 /** 954 * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank) 955 * @np: device node of the GPIO chip 956 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure 957 * @data: driver data to store in the struct gpio_chip 958 * 959 * To use this function you should allocate and fill mm_gc with: 960 * 961 * 1) In the gpio_chip structure: 962 * - all the callbacks 963 * - of_gpio_n_cells 964 * - of_xlate callback (optional) 965 * 966 * 3) In the of_mm_gpio_chip structure: 967 * - save_regs callback (optional) 968 * 969 * If succeeded, this function will map bank's memory and will 970 * do all necessary work for you. Then you'll able to use .regs 971 * to manage GPIOs from the callbacks. 972 */ 973 int of_mm_gpiochip_add_data(struct device_node *np, 974 struct of_mm_gpio_chip *mm_gc, 975 void *data) 976 { 977 int ret = -ENOMEM; 978 struct gpio_chip *gc = &mm_gc->gc; 979 980 gc->label = kasprintf(GFP_KERNEL, "%pOF", np); 981 if (!gc->label) 982 goto err0; 983 984 mm_gc->regs = of_iomap(np, 0); 985 if (!mm_gc->regs) 986 goto err1; 987 988 gc->base = -1; 989 990 if (mm_gc->save_regs) 991 mm_gc->save_regs(mm_gc); 992 993 fwnode_handle_put(mm_gc->gc.fwnode); 994 mm_gc->gc.fwnode = fwnode_handle_get(of_fwnode_handle(np)); 995 996 ret = gpiochip_add_data(gc, data); 997 if (ret) 998 goto err2; 999 1000 return 0; 1001 err2: 1002 of_node_put(np); 1003 iounmap(mm_gc->regs); 1004 err1: 1005 kfree(gc->label); 1006 err0: 1007 pr_err("%pOF: GPIO chip registration failed with status %d\n", np, ret); 1008 return ret; 1009 } 1010 EXPORT_SYMBOL_GPL(of_mm_gpiochip_add_data); 1011 1012 /** 1013 * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank) 1014 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure 1015 */ 1016 void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc) 1017 { 1018 struct gpio_chip *gc = &mm_gc->gc; 1019 1020 gpiochip_remove(gc); 1021 iounmap(mm_gc->regs); 1022 kfree(gc->label); 1023 } 1024 EXPORT_SYMBOL_GPL(of_mm_gpiochip_remove); 1025 #endif 1026 1027 #ifdef CONFIG_PINCTRL 1028 static int of_gpiochip_add_pin_range(struct gpio_chip *chip) 1029 { 1030 struct of_phandle_args pinspec; 1031 struct pinctrl_dev *pctldev; 1032 struct device_node *np; 1033 int index = 0, ret; 1034 const char *name; 1035 static const char group_names_propname[] = "gpio-ranges-group-names"; 1036 struct property *group_names; 1037 1038 np = dev_of_node(&chip->gpiodev->dev); 1039 if (!np) 1040 return 0; 1041 1042 group_names = of_find_property(np, group_names_propname, NULL); 1043 1044 for (;; index++) { 1045 ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, 1046 index, &pinspec); 1047 if (ret) 1048 break; 1049 1050 pctldev = of_pinctrl_get(pinspec.np); 1051 of_node_put(pinspec.np); 1052 if (!pctldev) 1053 return -EPROBE_DEFER; 1054 1055 if (pinspec.args[2]) { 1056 if (group_names) { 1057 of_property_read_string_index(np, 1058 group_names_propname, 1059 index, &name); 1060 if (strlen(name)) { 1061 pr_err("%pOF: Group name of numeric GPIO ranges must be the empty string.\n", 1062 np); 1063 break; 1064 } 1065 } 1066 /* npins != 0: linear range */ 1067 ret = gpiochip_add_pin_range(chip, 1068 pinctrl_dev_get_devname(pctldev), 1069 pinspec.args[0], 1070 pinspec.args[1], 1071 pinspec.args[2]); 1072 if (ret) 1073 return ret; 1074 } else { 1075 /* npins == 0: special range */ 1076 if (pinspec.args[1]) { 1077 pr_err("%pOF: Illegal gpio-range format.\n", 1078 np); 1079 break; 1080 } 1081 1082 if (!group_names) { 1083 pr_err("%pOF: GPIO group range requested but no %s property.\n", 1084 np, group_names_propname); 1085 break; 1086 } 1087 1088 ret = of_property_read_string_index(np, 1089 group_names_propname, 1090 index, &name); 1091 if (ret) 1092 break; 1093 1094 if (!strlen(name)) { 1095 pr_err("%pOF: Group name of GPIO group range cannot be the empty string.\n", 1096 np); 1097 break; 1098 } 1099 1100 ret = gpiochip_add_pingroup_range(chip, pctldev, 1101 pinspec.args[0], name); 1102 if (ret) 1103 return ret; 1104 } 1105 } 1106 1107 return 0; 1108 } 1109 1110 #else 1111 static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; } 1112 #endif 1113 1114 int of_gpiochip_add(struct gpio_chip *chip) 1115 { 1116 struct device_node *np; 1117 int ret; 1118 1119 np = dev_of_node(&chip->gpiodev->dev); 1120 if (!np) 1121 return 0; 1122 1123 if (!chip->of_xlate) { 1124 chip->of_gpio_n_cells = 2; 1125 chip->of_xlate = of_gpio_simple_xlate; 1126 } 1127 1128 if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS) 1129 return -EINVAL; 1130 1131 ret = of_gpiochip_add_pin_range(chip); 1132 if (ret) 1133 return ret; 1134 1135 of_node_get(np); 1136 1137 ret = of_gpiochip_scan_gpios(chip); 1138 if (ret) 1139 of_node_put(np); 1140 1141 return ret; 1142 } 1143 1144 void of_gpiochip_remove(struct gpio_chip *chip) 1145 { 1146 of_node_put(dev_of_node(&chip->gpiodev->dev)); 1147 } 1148