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 */ 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 */ 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 } 102 103 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 } 120 121 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 * 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 } 136 137 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 */ 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 */ 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_REGULATOR_S5M8767) 228 /* 229 * According to S5M8767, the DVS and DS pin are 230 * active-high signals. However, exynos5250-spring.dts use 231 * active-low setting. 232 */ 233 { "samsung,s5m8767-pmic", "s5m8767,pmic-buck-dvs-gpios", true }, 234 { "samsung,s5m8767-pmic", "s5m8767,pmic-buck-ds-gpios", true }, 235 #endif 236 #if IS_ENABLED(CONFIG_TOUCHSCREEN_TSC2005) 237 /* 238 * DTS for Nokia N900 incorrectly specified "active high" 239 * polarity for the reset line, while the chip actually 240 * treats it as "active low". 241 */ 242 { "ti,tsc2005", "reset-gpios", false }, 243 #endif 244 }; 245 unsigned int i; 246 247 for (i = 0; i < ARRAY_SIZE(gpios); i++) { 248 if (of_device_is_compatible(np, gpios[i].compatible) && 249 !strcmp(propname, gpios[i].propname)) { 250 of_gpio_quirk_polarity(np, gpios[i].active_high, flags); 251 break; 252 } 253 } 254 } 255 256 static void of_gpio_set_polarity_by_property(const struct device_node *np, 257 const char *propname, 258 enum of_gpio_flags *flags) 259 { 260 const struct device_node *np_compat = np; 261 const struct device_node *np_propname = np; 262 static const struct { 263 const char *compatible; 264 const char *gpio_propname; 265 const char *polarity_propname; 266 } gpios[] = { 267 #if IS_ENABLED(CONFIG_FEC) 268 /* Freescale Fast Ethernet Controller */ 269 { "fsl,imx25-fec", "phy-reset-gpios", "phy-reset-active-high" }, 270 { "fsl,imx27-fec", "phy-reset-gpios", "phy-reset-active-high" }, 271 { "fsl,imx28-fec", "phy-reset-gpios", "phy-reset-active-high" }, 272 { "fsl,imx6q-fec", "phy-reset-gpios", "phy-reset-active-high" }, 273 { "fsl,mvf600-fec", "phy-reset-gpios", "phy-reset-active-high" }, 274 { "fsl,imx6sx-fec", "phy-reset-gpios", "phy-reset-active-high" }, 275 { "fsl,imx6ul-fec", "phy-reset-gpios", "phy-reset-active-high" }, 276 { "fsl,imx8mq-fec", "phy-reset-gpios", "phy-reset-active-high" }, 277 { "fsl,imx8qm-fec", "phy-reset-gpios", "phy-reset-active-high" }, 278 { "fsl,s32v234-fec", "phy-reset-gpios", "phy-reset-active-high" }, 279 #endif 280 #if IS_ENABLED(CONFIG_MMC_ATMELMCI) 281 { "atmel,hsmci", "cd-gpios", "cd-inverted" }, 282 #endif 283 #if IS_ENABLED(CONFIG_PCI_IMX6) 284 { "fsl,imx6q-pcie", "reset-gpio", "reset-gpio-active-high" }, 285 { "fsl,imx6sx-pcie", "reset-gpio", "reset-gpio-active-high" }, 286 { "fsl,imx6qp-pcie", "reset-gpio", "reset-gpio-active-high" }, 287 { "fsl,imx7d-pcie", "reset-gpio", "reset-gpio-active-high" }, 288 { "fsl,imx8mq-pcie", "reset-gpio", "reset-gpio-active-high" }, 289 { "fsl,imx8mm-pcie", "reset-gpio", "reset-gpio-active-high" }, 290 { "fsl,imx8mp-pcie", "reset-gpio", "reset-gpio-active-high" }, 291 #endif 292 293 /* 294 * The regulator GPIO handles are specified such that the 295 * presence or absence of "enable-active-high" solely controls 296 * the polarity of the GPIO line. Any phandle flags must 297 * be actively ignored. 298 */ 299 #if IS_ENABLED(CONFIG_REGULATOR_FIXED_VOLTAGE) 300 { "regulator-fixed", "gpios", "enable-active-high" }, 301 { "regulator-fixed", "gpio", "enable-active-high" }, 302 { "reg-fixed-voltage", "gpios", "enable-active-high" }, 303 { "reg-fixed-voltage", "gpio", "enable-active-high" }, 304 #endif 305 #if IS_ENABLED(CONFIG_REGULATOR_GPIO) 306 { "regulator-gpio", "enable-gpio", "enable-active-high" }, 307 { "regulator-gpio", "enable-gpios", "enable-active-high" }, 308 #endif 309 }; 310 unsigned int i; 311 bool active_high; 312 313 #if IS_ENABLED(CONFIG_MMC_ATMELMCI) 314 /* 315 * The Atmel HSMCI has compatible property in the parent node and 316 * gpio property in a child node 317 */ 318 if (of_device_is_compatible(np->parent, "atmel,hsmci")) { 319 np_compat = np->parent; 320 np_propname = np; 321 } 322 #endif 323 324 for (i = 0; i < ARRAY_SIZE(gpios); i++) { 325 if (of_device_is_compatible(np_compat, gpios[i].compatible) && 326 !strcmp(propname, gpios[i].gpio_propname)) { 327 active_high = of_property_read_bool(np_propname, 328 gpios[i].polarity_propname); 329 of_gpio_quirk_polarity(np, active_high, flags); 330 break; 331 } 332 } 333 } 334 335 static void of_gpio_flags_quirks(const struct device_node *np, 336 const char *propname, 337 enum of_gpio_flags *flags, 338 int index) 339 { 340 of_gpio_try_fixup_polarity(np, propname, flags); 341 of_gpio_set_polarity_by_property(np, propname, flags); 342 343 /* 344 * Legacy open drain handling for fixed voltage regulators. 345 */ 346 if (IS_ENABLED(CONFIG_REGULATOR) && 347 of_device_is_compatible(np, "reg-fixed-voltage") && 348 of_property_read_bool(np, "gpio-open-drain")) { 349 *flags |= (OF_GPIO_SINGLE_ENDED | OF_GPIO_OPEN_DRAIN); 350 pr_info("%s uses legacy open drain flag - update the DTS if you can\n", 351 of_node_full_name(np)); 352 } 353 354 /* 355 * Legacy handling of SPI active high chip select. If we have a 356 * property named "cs-gpios" we need to inspect the child node 357 * to determine if the flags should have inverted semantics. 358 */ 359 if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") && 360 of_property_present(np, "cs-gpios")) { 361 u32 cs; 362 int ret; 363 364 for_each_child_of_node_scoped(np, child) { 365 ret = of_property_read_u32(child, "reg", &cs); 366 if (ret) 367 continue; 368 if (cs == index) { 369 /* 370 * SPI children have active low chip selects 371 * by default. This can be specified negatively 372 * by just omitting "spi-cs-high" in the 373 * device node, or actively by tagging on 374 * GPIO_ACTIVE_LOW as flag in the device 375 * tree. If the line is simultaneously 376 * tagged as active low in the device tree 377 * and has the "spi-cs-high" set, we get a 378 * conflict and the "spi-cs-high" flag will 379 * take precedence. 380 */ 381 bool active_high = of_property_read_bool(child, 382 "spi-cs-high"); 383 of_gpio_quirk_polarity(child, active_high, 384 flags); 385 break; 386 } 387 } 388 } 389 390 /* Legacy handling of stmmac's active-low PHY reset line */ 391 if (IS_ENABLED(CONFIG_STMMAC_ETH) && 392 !strcmp(propname, "snps,reset-gpio") && 393 of_property_read_bool(np, "snps,reset-active-low")) 394 *flags |= OF_GPIO_ACTIVE_LOW; 395 } 396 397 /** 398 * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API 399 * @np: device node to get GPIO from 400 * @propname: property name containing gpio specifier(s) 401 * @index: index of the GPIO 402 * @flags: a flags pointer to fill in 403 * 404 * Returns: 405 * GPIO descriptor to use with Linux GPIO API, or one of the errno 406 * value on the error condition. If @flags is not NULL the function also fills 407 * in flags for the GPIO. 408 */ 409 static struct gpio_desc *of_get_named_gpiod_flags(const struct device_node *np, 410 const char *propname, int index, enum of_gpio_flags *flags) 411 { 412 struct of_phandle_args gpiospec; 413 struct gpio_desc *desc; 414 int ret; 415 416 ret = of_parse_phandle_with_args_map(np, propname, "gpio", index, 417 &gpiospec); 418 if (ret) { 419 pr_debug("%s: can't parse '%s' property of node '%pOF[%d]'\n", 420 __func__, propname, np, index); 421 return ERR_PTR(ret); 422 } 423 424 struct gpio_device *gdev __free(gpio_device_put) = 425 of_find_gpio_device_by_xlate(&gpiospec); 426 if (!gdev) { 427 desc = ERR_PTR(-EPROBE_DEFER); 428 goto out; 429 } 430 431 desc = of_xlate_and_get_gpiod_flags(gpio_device_get_chip(gdev), 432 &gpiospec, flags); 433 if (IS_ERR(desc)) 434 goto out; 435 436 if (flags) 437 of_gpio_flags_quirks(np, propname, flags, index); 438 439 pr_debug("%s: parsed '%s' property of node '%pOF[%d]' - status (%d)\n", 440 __func__, propname, np, index, 441 PTR_ERR_OR_ZERO(desc)); 442 443 out: 444 of_node_put(gpiospec.np); 445 446 return desc; 447 } 448 449 /** 450 * of_get_named_gpio() - Get a GPIO number to use with GPIO API 451 * @np: device node to get GPIO from 452 * @propname: Name of property containing gpio specifier(s) 453 * @index: index of the GPIO 454 * 455 * **DEPRECATED** This function is deprecated and must not be used in new code. 456 * 457 * Returns: 458 * GPIO number to use with Linux generic GPIO API, or one of the errno 459 * value on the error condition. 460 */ 461 int of_get_named_gpio(const struct device_node *np, const char *propname, 462 int index) 463 { 464 struct gpio_desc *desc; 465 466 desc = of_get_named_gpiod_flags(np, propname, index, NULL); 467 468 if (IS_ERR(desc)) 469 return PTR_ERR(desc); 470 else 471 return desc_to_gpio(desc); 472 } 473 EXPORT_SYMBOL_GPL(of_get_named_gpio); 474 475 /* Converts gpio_lookup_flags into bitmask of GPIO_* values */ 476 static unsigned long of_convert_gpio_flags(enum of_gpio_flags flags) 477 { 478 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT; 479 480 if (flags & OF_GPIO_ACTIVE_LOW) 481 lflags |= GPIO_ACTIVE_LOW; 482 483 if (flags & OF_GPIO_SINGLE_ENDED) { 484 if (flags & OF_GPIO_OPEN_DRAIN) 485 lflags |= GPIO_OPEN_DRAIN; 486 else 487 lflags |= GPIO_OPEN_SOURCE; 488 } 489 490 if (flags & OF_GPIO_TRANSITORY) 491 lflags |= GPIO_TRANSITORY; 492 493 if (flags & OF_GPIO_PULL_UP) 494 lflags |= GPIO_PULL_UP; 495 496 if (flags & OF_GPIO_PULL_DOWN) 497 lflags |= GPIO_PULL_DOWN; 498 499 if (flags & OF_GPIO_PULL_DISABLE) 500 lflags |= GPIO_PULL_DISABLE; 501 502 return lflags; 503 } 504 505 static struct gpio_desc *of_find_gpio_rename(struct device_node *np, 506 const char *con_id, 507 unsigned int idx, 508 enum of_gpio_flags *of_flags) 509 { 510 static const struct of_rename_gpio { 511 const char *con_id; 512 const char *legacy_id; /* NULL - same as con_id */ 513 /* 514 * Compatible string can be set to NULL in case where 515 * matching to a particular compatible is not practical, 516 * but it should only be done for gpio names that have 517 * vendor prefix to reduce risk of false positives. 518 * Addition of such entries is strongly discouraged. 519 */ 520 const char *compatible; 521 } gpios[] = { 522 #if IS_ENABLED(CONFIG_LCD_HX8357) 523 /* Himax LCD controllers used "gpios-reset" */ 524 { "reset", "gpios-reset", "himax,hx8357" }, 525 { "reset", "gpios-reset", "himax,hx8369" }, 526 #endif 527 #if IS_ENABLED(CONFIG_MFD_ARIZONA) 528 { "wlf,reset", NULL, NULL }, 529 #endif 530 #if IS_ENABLED(CONFIG_RTC_DRV_MOXART) 531 { "rtc-data", "gpio-rtc-data", "moxa,moxart-rtc" }, 532 { "rtc-sclk", "gpio-rtc-sclk", "moxa,moxart-rtc" }, 533 { "rtc-reset", "gpio-rtc-reset", "moxa,moxart-rtc" }, 534 #endif 535 #if IS_ENABLED(CONFIG_NFC_MRVL_I2C) 536 { "reset", "reset-n-io", "marvell,nfc-i2c" }, 537 #endif 538 #if IS_ENABLED(CONFIG_NFC_MRVL_SPI) 539 { "reset", "reset-n-io", "marvell,nfc-spi" }, 540 #endif 541 #if IS_ENABLED(CONFIG_NFC_MRVL_UART) 542 { "reset", "reset-n-io", "marvell,nfc-uart" }, 543 { "reset", "reset-n-io", "mrvl,nfc-uart" }, 544 #endif 545 #if IS_ENABLED(CONFIG_PCI_LANTIQ) 546 /* MIPS Lantiq PCI */ 547 { "reset", "gpio-reset", "lantiq,pci-xway" }, 548 #endif 549 550 /* 551 * Some regulator bindings happened before we managed to 552 * establish that GPIO properties should be named 553 * "foo-gpios" so we have this special kludge for them. 554 */ 555 #if IS_ENABLED(CONFIG_REGULATOR_ARIZONA_LDO1) 556 { "wlf,ldoena", NULL, NULL }, /* Arizona */ 557 #endif 558 #if IS_ENABLED(CONFIG_REGULATOR_WM8994) 559 { "wlf,ldo1ena", NULL, NULL }, /* WM8994 */ 560 { "wlf,ldo2ena", NULL, NULL }, /* WM8994 */ 561 #endif 562 563 #if IS_ENABLED(CONFIG_SND_SOC_CS42L56) 564 { "reset", "cirrus,gpio-nreset", "cirrus,cs42l56" }, 565 #endif 566 #if IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448) 567 { "i2s1-in-sel-gpio1", NULL, "mediatek,mt2701-cs42448-machine" }, 568 { "i2s1-in-sel-gpio2", NULL, "mediatek,mt2701-cs42448-machine" }, 569 #endif 570 #if IS_ENABLED(CONFIG_SND_SOC_TLV320AIC3X) 571 { "reset", "gpio-reset", "ti,tlv320aic3x" }, 572 { "reset", "gpio-reset", "ti,tlv320aic33" }, 573 { "reset", "gpio-reset", "ti,tlv320aic3007" }, 574 { "reset", "gpio-reset", "ti,tlv320aic3104" }, 575 { "reset", "gpio-reset", "ti,tlv320aic3106" }, 576 #endif 577 #if IS_ENABLED(CONFIG_SPI_GPIO) 578 /* 579 * The SPI GPIO bindings happened before we managed to 580 * establish that GPIO properties should be named 581 * "foo-gpios" so we have this special kludge for them. 582 */ 583 { "miso", "gpio-miso", "spi-gpio" }, 584 { "mosi", "gpio-mosi", "spi-gpio" }, 585 { "sck", "gpio-sck", "spi-gpio" }, 586 #endif 587 588 /* 589 * The old Freescale bindings use simply "gpios" as name 590 * for the chip select lines rather than "cs-gpios" like 591 * all other SPI hardware. Allow this specifically for 592 * Freescale and PPC devices. 593 */ 594 #if IS_ENABLED(CONFIG_SPI_FSL_SPI) 595 { "cs", "gpios", "fsl,spi" }, 596 { "cs", "gpios", "aeroflexgaisler,spictrl" }, 597 #endif 598 #if IS_ENABLED(CONFIG_SPI_PPC4xx) 599 { "cs", "gpios", "ibm,ppc4xx-spi" }, 600 #endif 601 602 #if IS_ENABLED(CONFIG_TYPEC_FUSB302) 603 /* 604 * Fairchild FUSB302 host is using undocumented "fcs,int_n" 605 * property without the compulsory "-gpios" suffix. 606 */ 607 { "fcs,int_n", NULL, "fcs,fusb302" }, 608 #endif 609 }; 610 struct gpio_desc *desc; 611 const char *legacy_id; 612 unsigned int i; 613 614 if (!con_id) 615 return ERR_PTR(-ENOENT); 616 617 for (i = 0; i < ARRAY_SIZE(gpios); i++) { 618 if (strcmp(con_id, gpios[i].con_id)) 619 continue; 620 621 if (gpios[i].compatible && 622 !of_device_is_compatible(np, gpios[i].compatible)) 623 continue; 624 625 legacy_id = gpios[i].legacy_id ?: gpios[i].con_id; 626 desc = of_get_named_gpiod_flags(np, legacy_id, idx, of_flags); 627 if (!gpiod_not_found(desc)) { 628 pr_info("%s uses legacy gpio name '%s' instead of '%s-gpios'\n", 629 of_node_full_name(np), legacy_id, con_id); 630 return desc; 631 } 632 } 633 634 return ERR_PTR(-ENOENT); 635 } 636 637 #if IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448) 638 static struct gpio_desc *of_find_mt2701_gpio(struct device_node *np, 639 const char *con_id, 640 unsigned int idx, 641 enum of_gpio_flags *of_flags) 642 { 643 struct gpio_desc *desc; 644 const char *legacy_id; 645 646 if (!IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448)) 647 return ERR_PTR(-ENOENT); 648 649 if (!of_device_is_compatible(np, "mediatek,mt2701-cs42448-machine")) 650 return ERR_PTR(-ENOENT); 651 652 if (!con_id || strcmp(con_id, "i2s1-in-sel")) 653 return ERR_PTR(-ENOENT); 654 655 if (idx == 0) 656 legacy_id = "i2s1-in-sel-gpio1"; 657 else if (idx == 1) 658 legacy_id = "i2s1-in-sel-gpio2"; 659 else 660 return ERR_PTR(-ENOENT); 661 662 desc = of_get_named_gpiod_flags(np, legacy_id, 0, of_flags); 663 if (!gpiod_not_found(desc)) 664 pr_info("%s is using legacy gpio name '%s' instead of '%s-gpios'\n", 665 of_node_full_name(np), legacy_id, con_id); 666 667 return desc; 668 } 669 #endif 670 671 /* 672 * Trigger sources are special, they allow us to use any GPIO as a LED trigger 673 * and have the name "trigger-sources" no matter which kind of phandle it is 674 * pointing to, whether to a GPIO, a USB host, a network PHY etc. So in this case 675 * we allow looking something up that is not named "foo-gpios". 676 */ 677 static struct gpio_desc *of_find_trigger_gpio(struct device_node *np, 678 const char *con_id, 679 unsigned int idx, 680 enum of_gpio_flags *of_flags) 681 { 682 struct gpio_desc *desc; 683 684 if (!IS_ENABLED(CONFIG_LEDS_TRIGGER_GPIO)) 685 return ERR_PTR(-ENOENT); 686 687 if (!con_id || strcmp(con_id, "trigger-sources")) 688 return ERR_PTR(-ENOENT); 689 690 desc = of_get_named_gpiod_flags(np, con_id, idx, of_flags); 691 if (!gpiod_not_found(desc)) 692 pr_debug("%s is used as a trigger\n", of_node_full_name(np)); 693 694 return desc; 695 } 696 697 698 typedef struct gpio_desc *(*of_find_gpio_quirk)(struct device_node *np, 699 const char *con_id, 700 unsigned int idx, 701 enum of_gpio_flags *of_flags); 702 static const of_find_gpio_quirk of_find_gpio_quirks[] = { 703 of_find_gpio_rename, 704 #if IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448) 705 of_find_mt2701_gpio, 706 #endif 707 of_find_trigger_gpio, 708 NULL 709 }; 710 711 struct gpio_desc *of_find_gpio(struct device_node *np, const char *con_id, 712 unsigned int idx, unsigned long *flags) 713 { 714 char propname[32]; /* 32 is max size of property name */ 715 enum of_gpio_flags of_flags = 0; 716 const of_find_gpio_quirk *q; 717 struct gpio_desc *desc; 718 719 /* Try GPIO property "foo-gpios" and "foo-gpio" */ 720 for_each_gpio_property_name(propname, con_id) { 721 desc = of_get_named_gpiod_flags(np, propname, idx, &of_flags); 722 if (!gpiod_not_found(desc)) 723 break; 724 } 725 726 /* Properly named GPIO was not found, try workarounds */ 727 for (q = of_find_gpio_quirks; gpiod_not_found(desc) && *q; q++) 728 desc = (*q)(np, con_id, idx, &of_flags); 729 730 if (IS_ERR(desc)) 731 return desc; 732 733 *flags = of_convert_gpio_flags(of_flags); 734 735 return desc; 736 } 737 738 /** 739 * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API 740 * @np: device node to get GPIO from 741 * @chip: GPIO chip whose hog is parsed 742 * @idx: Index of the GPIO to parse 743 * @name: GPIO line name 744 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from 745 * of_find_gpio() or of_parse_own_gpio() 746 * @dflags: gpiod_flags - optional GPIO initialization flags 747 * 748 * Returns: 749 * GPIO descriptor to use with Linux GPIO API, or one of the errno 750 * value on the error condition. 751 */ 752 static struct gpio_desc *of_parse_own_gpio(struct device_node *np, 753 struct gpio_chip *chip, 754 unsigned int idx, const char **name, 755 unsigned long *lflags, 756 enum gpiod_flags *dflags) 757 { 758 struct device_node *chip_np; 759 enum of_gpio_flags xlate_flags; 760 struct of_phandle_args gpiospec; 761 struct gpio_desc *desc; 762 unsigned int i; 763 u32 tmp; 764 int ret; 765 766 chip_np = dev_of_node(&chip->gpiodev->dev); 767 if (!chip_np) 768 return ERR_PTR(-EINVAL); 769 770 xlate_flags = 0; 771 *lflags = GPIO_LOOKUP_FLAGS_DEFAULT; 772 *dflags = GPIOD_ASIS; 773 774 ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp); 775 if (ret) 776 return ERR_PTR(ret); 777 778 gpiospec.np = chip_np; 779 gpiospec.args_count = tmp; 780 781 for (i = 0; i < tmp; i++) { 782 ret = of_property_read_u32_index(np, "gpios", idx * tmp + i, 783 &gpiospec.args[i]); 784 if (ret) 785 return ERR_PTR(ret); 786 } 787 788 desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, &xlate_flags); 789 if (IS_ERR(desc)) 790 return desc; 791 792 *lflags = of_convert_gpio_flags(xlate_flags); 793 794 if (of_property_read_bool(np, "input")) 795 *dflags |= GPIOD_IN; 796 else if (of_property_read_bool(np, "output-low")) 797 *dflags |= GPIOD_OUT_LOW; 798 else if (of_property_read_bool(np, "output-high")) 799 *dflags |= GPIOD_OUT_HIGH; 800 else { 801 pr_warn("GPIO line %d (%pOFn): no hogging state specified, bailing out\n", 802 desc_to_gpio(desc), np); 803 return ERR_PTR(-EINVAL); 804 } 805 806 if (name && of_property_read_string(np, "line-name", name)) 807 *name = np->name; 808 809 return desc; 810 } 811 812 /** 813 * of_gpiochip_add_hog - Add all hogs in a hog device node 814 * @chip: gpio chip to act on 815 * @hog: device node describing the hogs 816 * 817 * Returns: 818 * 0 on success, or negative errno on failure. 819 */ 820 static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog) 821 { 822 enum gpiod_flags dflags; 823 struct gpio_desc *desc; 824 unsigned long lflags; 825 const char *name; 826 unsigned int i; 827 int ret; 828 829 for (i = 0;; i++) { 830 desc = of_parse_own_gpio(hog, chip, i, &name, &lflags, &dflags); 831 if (IS_ERR(desc)) 832 break; 833 834 ret = gpiod_hog(desc, name, lflags, dflags); 835 if (ret < 0) 836 return ret; 837 838 #ifdef CONFIG_OF_DYNAMIC 839 WRITE_ONCE(desc->hog, hog); 840 #endif 841 } 842 843 return 0; 844 } 845 846 /** 847 * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions 848 * @chip: gpio chip to act on 849 * 850 * This is only used by of_gpiochip_add to request/set GPIO initial 851 * configuration. 852 * 853 * Returns: 854 * 0 on success, or negative errno on failure. 855 */ 856 static int of_gpiochip_scan_gpios(struct gpio_chip *chip) 857 { 858 int ret; 859 860 for_each_available_child_of_node_scoped(dev_of_node(&chip->gpiodev->dev), np) { 861 if (!of_property_read_bool(np, "gpio-hog")) 862 continue; 863 864 ret = of_gpiochip_add_hog(chip, np); 865 if (ret < 0) 866 return ret; 867 868 of_node_set_flag(np, OF_POPULATED); 869 } 870 871 return 0; 872 } 873 874 #ifdef CONFIG_OF_DYNAMIC 875 /** 876 * of_gpiochip_remove_hog - Remove all hogs in a hog device node 877 * @chip: gpio chip to act on 878 * @hog: device node describing the hogs 879 */ 880 static void of_gpiochip_remove_hog(struct gpio_chip *chip, 881 struct device_node *hog) 882 { 883 struct gpio_desc *desc; 884 885 for_each_gpio_desc_with_flag(chip, desc, GPIOD_FLAG_IS_HOGGED) 886 if (READ_ONCE(desc->hog) == hog) 887 gpiochip_free_own_desc(desc); 888 } 889 890 static int of_gpiochip_match_node(struct gpio_chip *chip, const void *data) 891 { 892 return device_match_of_node(&chip->gpiodev->dev, data); 893 } 894 895 static struct gpio_device *of_find_gpio_device_by_node(struct device_node *np) 896 { 897 return gpio_device_find(np, of_gpiochip_match_node); 898 } 899 900 static int of_gpio_notify(struct notifier_block *nb, unsigned long action, 901 void *arg) 902 { 903 struct gpio_device *gdev __free(gpio_device_put) = NULL; 904 struct of_reconfig_data *rd = arg; 905 int ret; 906 907 /* 908 * This only supports adding and removing complete gpio-hog nodes. 909 * Modifying an existing gpio-hog node is not supported (except for 910 * changing its "status" property, which is treated the same as 911 * addition/removal). 912 */ 913 switch (of_reconfig_get_state_change(action, arg)) { 914 case OF_RECONFIG_CHANGE_ADD: 915 if (!of_property_read_bool(rd->dn, "gpio-hog")) 916 return NOTIFY_DONE; /* not for us */ 917 918 if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) 919 return NOTIFY_DONE; 920 921 gdev = of_find_gpio_device_by_node(rd->dn->parent); 922 if (!gdev) 923 return NOTIFY_DONE; /* not for us */ 924 925 ret = of_gpiochip_add_hog(gpio_device_get_chip(gdev), rd->dn); 926 if (ret < 0) { 927 pr_err("%s: failed to add hogs for %pOF\n", __func__, 928 rd->dn); 929 of_node_clear_flag(rd->dn, OF_POPULATED); 930 return notifier_from_errno(ret); 931 } 932 return NOTIFY_OK; 933 934 case OF_RECONFIG_CHANGE_REMOVE: 935 if (!of_node_check_flag(rd->dn, OF_POPULATED)) 936 return NOTIFY_DONE; /* already depopulated */ 937 938 gdev = of_find_gpio_device_by_node(rd->dn->parent); 939 if (!gdev) 940 return NOTIFY_DONE; /* not for us */ 941 942 of_gpiochip_remove_hog(gpio_device_get_chip(gdev), rd->dn); 943 of_node_clear_flag(rd->dn, OF_POPULATED); 944 return NOTIFY_OK; 945 } 946 947 return NOTIFY_DONE; 948 } 949 950 struct notifier_block gpio_of_notifier = { 951 .notifier_call = of_gpio_notify, 952 }; 953 #endif /* CONFIG_OF_DYNAMIC */ 954 955 /** 956 * of_gpio_twocell_xlate - translate twocell gpiospec to the GPIO number and flags 957 * @gc: pointer to the gpio_chip structure 958 * @gpiospec: GPIO specifier as found in the device tree 959 * @flags: a flags pointer to fill in 960 * 961 * This is simple translation function, suitable for the most 1:1 mapped 962 * GPIO chips. This function performs only one sanity check: whether GPIO 963 * is less than ngpios (that is specified in the gpio_chip). 964 * 965 * Returns: 966 * GPIO number (>= 0) on success, negative errno on failure. 967 */ 968 static int of_gpio_twocell_xlate(struct gpio_chip *gc, 969 const struct of_phandle_args *gpiospec, 970 u32 *flags) 971 { 972 /* 973 * We're discouraging gpio_cells < 2, since that way you'll have to 974 * write your own xlate function (that will have to retrieve the GPIO 975 * number and the flags from a single gpio cell -- this is possible, 976 * but not recommended). 977 */ 978 if (gc->of_gpio_n_cells != 2) { 979 WARN_ON(1); 980 return -EINVAL; 981 } 982 983 if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells)) 984 return -EINVAL; 985 986 if (gpiospec->args[0] >= gc->ngpio) 987 return -EINVAL; 988 989 if (flags) 990 *flags = gpiospec->args[1]; 991 992 return gpiospec->args[0]; 993 } 994 995 /** 996 * of_gpio_threecell_xlate - translate threecell gpiospec to the GPIO number and flags 997 * @gc: pointer to the gpio_chip structure 998 * @gpiospec: GPIO specifier as found in the device tree 999 * @flags: a flags pointer to fill in 1000 * 1001 * This is simple translation function, suitable for the most 1:n mapped 1002 * GPIO chips, i.e. several GPIO chip instances from one device tree node. 1003 * In this case the following binding is implied: 1004 * 1005 * foo-gpios = <&gpio instance offset flags>; 1006 * 1007 * Returns: 1008 * GPIO number (>= 0) on success, negative errno on failure. 1009 */ 1010 static int of_gpio_threecell_xlate(struct gpio_chip *gc, 1011 const struct of_phandle_args *gpiospec, 1012 u32 *flags) 1013 { 1014 if (gc->of_gpio_n_cells != 3) { 1015 WARN_ON(1); 1016 return -EINVAL; 1017 } 1018 1019 if (WARN_ON(gpiospec->args_count != 3)) 1020 return -EINVAL; 1021 1022 /* 1023 * Check chip instance number, the driver responds with true if 1024 * this is the chip we are looking for. 1025 */ 1026 if (!gc->of_node_instance_match(gc, gpiospec->args[0])) 1027 return -EINVAL; 1028 1029 if (gpiospec->args[1] >= gc->ngpio) 1030 return -EINVAL; 1031 1032 if (flags) 1033 *flags = gpiospec->args[2]; 1034 1035 return gpiospec->args[1]; 1036 } 1037 1038 #ifdef CONFIG_PINCTRL 1039 static int of_gpiochip_add_pin_range(struct gpio_chip *chip) 1040 { 1041 struct of_phandle_args pinspec; 1042 struct pinctrl_dev *pctldev; 1043 struct device_node *np; 1044 int index = 0, ret, trim; 1045 const char *name; 1046 static const char group_names_propname[] = "gpio-ranges-group-names"; 1047 bool has_group_names; 1048 int offset; /* Offset of the first GPIO line on the chip */ 1049 int pin; /* Pin base number in the range */ 1050 int count; /* Number of pins/GPIO lines to map */ 1051 1052 np = dev_of_node(&chip->gpiodev->dev); 1053 if (!np) 1054 return 0; 1055 1056 has_group_names = of_property_present(np, group_names_propname); 1057 1058 for (;; index++) { 1059 /* 1060 * Ordinary phandles contain 2-3 cells: 1061 * gpios = <&gpio [instance] offset flags>; 1062 * Ranges always contain one more cell: 1063 * gpio-ranges <&pinctrl [gpio_instance] gpio_offet pin_offet count>; 1064 * This is why we parse chip->of_gpio_n_cells + 1 cells 1065 */ 1066 ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 1067 chip->of_gpio_n_cells + 1, 1068 index, &pinspec); 1069 if (ret) 1070 break; 1071 1072 pctldev = of_pinctrl_get(pinspec.np); 1073 of_node_put(pinspec.np); 1074 if (!pctldev) 1075 return -EPROBE_DEFER; 1076 1077 if (chip->of_gpio_n_cells == 3) { 1078 /* First cell is the gpiochip instance number */ 1079 offset = pinspec.args[1]; 1080 pin = pinspec.args[2]; 1081 count = pinspec.args[3]; 1082 } else { 1083 offset = pinspec.args[0]; 1084 pin = pinspec.args[1]; 1085 count = pinspec.args[2]; 1086 } 1087 1088 /* 1089 * With multiple GPIO chips per node, check that this chip is the 1090 * right instance. 1091 */ 1092 if (chip->of_node_instance_match && 1093 (chip->of_gpio_n_cells == 3) && 1094 !chip->of_node_instance_match(chip, pinspec.args[0])) 1095 continue; 1096 1097 /* Ignore ranges outside of this GPIO chip */ 1098 if (offset >= (chip->offset + chip->ngpio)) 1099 continue; 1100 if (offset + count <= chip->offset) 1101 continue; 1102 1103 if (count) { 1104 /* npins != 0: linear range */ 1105 if (has_group_names) { 1106 of_property_read_string_index(np, 1107 group_names_propname, 1108 index, &name); 1109 if (strlen(name)) { 1110 pr_err("%pOF: Group name of numeric GPIO ranges must be the empty string.\n", 1111 np); 1112 break; 1113 } 1114 } 1115 1116 /* Trim the range to fit this GPIO chip */ 1117 if (chip->offset > offset) { 1118 trim = chip->offset - offset; 1119 count -= trim; 1120 pin += trim; 1121 offset = 0; 1122 } else { 1123 offset -= chip->offset; 1124 } 1125 if ((offset + count) > chip->ngpio) 1126 count = chip->ngpio - offset; 1127 1128 ret = gpiochip_add_pin_range(chip, 1129 pinctrl_dev_get_devname(pctldev), 1130 offset, 1131 pin, 1132 count); 1133 if (ret) 1134 return ret; 1135 } else { 1136 /* npins == 0: special range */ 1137 if (pin) { 1138 pr_err("%pOF: Illegal gpio-range format.\n", 1139 np); 1140 break; 1141 } 1142 1143 if (!has_group_names) { 1144 pr_err("%pOF: GPIO group range requested but no %s property.\n", 1145 np, group_names_propname); 1146 break; 1147 } 1148 1149 ret = of_property_read_string_index(np, 1150 group_names_propname, 1151 index, &name); 1152 if (ret) 1153 break; 1154 1155 if (!strlen(name)) { 1156 pr_err("%pOF: Group name of GPIO group range cannot be the empty string.\n", 1157 np); 1158 break; 1159 } 1160 1161 ret = gpiochip_add_pingroup_range(chip, pctldev, 1162 offset, name); 1163 if (ret) 1164 return ret; 1165 } 1166 } 1167 1168 return 0; 1169 } 1170 1171 #else 1172 static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; } 1173 #endif 1174 1175 int of_gpiochip_add(struct gpio_chip *chip) 1176 { 1177 struct device_node *np; 1178 int ret; 1179 1180 np = dev_of_node(&chip->gpiodev->dev); 1181 if (!np) 1182 return 0; 1183 1184 if (!chip->of_xlate) { 1185 if (chip->of_gpio_n_cells == 3) { 1186 if (!chip->of_node_instance_match) 1187 return -EINVAL; 1188 chip->of_xlate = of_gpio_threecell_xlate; 1189 } else { 1190 chip->of_gpio_n_cells = 2; 1191 chip->of_xlate = of_gpio_twocell_xlate; 1192 } 1193 } 1194 1195 if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS) 1196 return -EINVAL; 1197 1198 ret = of_gpiochip_add_pin_range(chip); 1199 if (ret) 1200 return ret; 1201 1202 of_node_get(np); 1203 1204 ret = of_gpiochip_scan_gpios(chip); 1205 if (ret) 1206 of_node_put(np); 1207 1208 return ret; 1209 } 1210 1211 void of_gpiochip_remove(struct gpio_chip *chip) 1212 { 1213 of_node_put(dev_of_node(&chip->gpiodev->dev)); 1214 } 1215 1216 bool of_gpiochip_instance_match(struct gpio_chip *gc, unsigned int index) 1217 { 1218 if (gc->of_node_instance_match) 1219 return gc->of_node_instance_match(gc, index); 1220 1221 return false; 1222 } 1223