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