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 * @np: Consuming device node 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(const struct device_node *np, 82 const char *con_id) 83 { 84 if (!IS_ENABLED(CONFIG_SPI_MASTER)) 85 return 0; 86 if (!con_id || strcmp(con_id, "cs")) 87 return 0; 88 if (!of_device_is_compatible(np, "fsl,spi") && 89 !of_device_is_compatible(np, "aeroflexgaisler,spictrl") && 90 !of_device_is_compatible(np, "ibm,ppc4xx-spi")) 91 return 0; 92 return of_gpio_named_count(np, "gpios"); 93 } 94 95 int of_gpio_count(const struct fwnode_handle *fwnode, const char *con_id) 96 { 97 const struct device_node *np = to_of_node(fwnode); 98 int ret; 99 char propname[32]; 100 unsigned int i; 101 102 ret = of_gpio_spi_cs_get_count(np, con_id); 103 if (ret > 0) 104 return ret; 105 106 for (i = 0; i < gpio_suffix_count; 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(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_PCI_LANTIQ) 207 /* 208 * According to the PCI specification, the RST# pin is an 209 * active-low signal. However, most of the device trees that 210 * have been widely used for a long time incorrectly describe 211 * reset GPIO as active-high, and were also using wrong name 212 * for the property. 213 */ 214 { "lantiq,pci-xway", "gpio-reset", false }, 215 #endif 216 #if IS_ENABLED(CONFIG_TOUCHSCREEN_TSC2005) 217 /* 218 * DTS for Nokia N900 incorrectly specified "active high" 219 * polarity for the reset line, while the chip actually 220 * treats it as "active low". 221 */ 222 { "ti,tsc2005", "reset-gpios", false }, 223 #endif 224 }; 225 unsigned int i; 226 227 for (i = 0; i < ARRAY_SIZE(gpios); i++) { 228 if (of_device_is_compatible(np, gpios[i].compatible) && 229 !strcmp(propname, gpios[i].propname)) { 230 of_gpio_quirk_polarity(np, gpios[i].active_high, flags); 231 break; 232 } 233 } 234 } 235 236 static void of_gpio_set_polarity_by_property(const struct device_node *np, 237 const char *propname, 238 enum of_gpio_flags *flags) 239 { 240 const struct device_node *np_compat = np; 241 const struct device_node *np_propname = np; 242 static const struct { 243 const char *compatible; 244 const char *gpio_propname; 245 const char *polarity_propname; 246 } gpios[] = { 247 #if IS_ENABLED(CONFIG_FEC) 248 /* Freescale Fast Ethernet Controller */ 249 { "fsl,imx25-fec", "phy-reset-gpios", "phy-reset-active-high" }, 250 { "fsl,imx27-fec", "phy-reset-gpios", "phy-reset-active-high" }, 251 { "fsl,imx28-fec", "phy-reset-gpios", "phy-reset-active-high" }, 252 { "fsl,imx6q-fec", "phy-reset-gpios", "phy-reset-active-high" }, 253 { "fsl,mvf600-fec", "phy-reset-gpios", "phy-reset-active-high" }, 254 { "fsl,imx6sx-fec", "phy-reset-gpios", "phy-reset-active-high" }, 255 { "fsl,imx6ul-fec", "phy-reset-gpios", "phy-reset-active-high" }, 256 { "fsl,imx8mq-fec", "phy-reset-gpios", "phy-reset-active-high" }, 257 { "fsl,imx8qm-fec", "phy-reset-gpios", "phy-reset-active-high" }, 258 { "fsl,s32v234-fec", "phy-reset-gpios", "phy-reset-active-high" }, 259 #endif 260 #if IS_ENABLED(CONFIG_PCI_IMX6) 261 { "fsl,imx6q-pcie", "reset-gpio", "reset-gpio-active-high" }, 262 { "fsl,imx6sx-pcie", "reset-gpio", "reset-gpio-active-high" }, 263 { "fsl,imx6qp-pcie", "reset-gpio", "reset-gpio-active-high" }, 264 { "fsl,imx7d-pcie", "reset-gpio", "reset-gpio-active-high" }, 265 { "fsl,imx8mq-pcie", "reset-gpio", "reset-gpio-active-high" }, 266 { "fsl,imx8mm-pcie", "reset-gpio", "reset-gpio-active-high" }, 267 { "fsl,imx8mp-pcie", "reset-gpio", "reset-gpio-active-high" }, 268 #endif 269 270 /* 271 * The regulator GPIO handles are specified such that the 272 * presence or absence of "enable-active-high" solely controls 273 * the polarity of the GPIO line. Any phandle flags must 274 * be actively ignored. 275 */ 276 #if IS_ENABLED(CONFIG_REGULATOR_FIXED_VOLTAGE) 277 { "regulator-fixed", "gpios", "enable-active-high" }, 278 { "regulator-fixed", "gpio", "enable-active-high" }, 279 { "reg-fixed-voltage", "gpios", "enable-active-high" }, 280 { "reg-fixed-voltage", "gpio", "enable-active-high" }, 281 #endif 282 #if IS_ENABLED(CONFIG_REGULATOR_GPIO) 283 { "regulator-gpio", "enable-gpio", "enable-active-high" }, 284 { "regulator-gpio", "enable-gpios", "enable-active-high" }, 285 #endif 286 #if IS_ENABLED(CONFIG_MMC_ATMELMCI) 287 { "atmel,hsmci", "cd-gpios", "cd-inverted" }, 288 #endif 289 }; 290 unsigned int i; 291 bool active_high; 292 293 #if IS_ENABLED(CONFIG_MMC_ATMELMCI) 294 /* 295 * The Atmel HSMCI has compatible property in the parent node and 296 * gpio property in a child node 297 */ 298 if (of_device_is_compatible(np->parent, "atmel,hsmci")) { 299 np_compat = np->parent; 300 np_propname = np; 301 } 302 #endif 303 304 for (i = 0; i < ARRAY_SIZE(gpios); i++) { 305 if (of_device_is_compatible(np_compat, gpios[i].compatible) && 306 !strcmp(propname, gpios[i].gpio_propname)) { 307 active_high = of_property_read_bool(np_propname, 308 gpios[i].polarity_propname); 309 of_gpio_quirk_polarity(np, active_high, flags); 310 break; 311 } 312 } 313 } 314 315 static void of_gpio_flags_quirks(const struct device_node *np, 316 const char *propname, 317 enum of_gpio_flags *flags, 318 int index) 319 { 320 of_gpio_try_fixup_polarity(np, propname, flags); 321 of_gpio_set_polarity_by_property(np, propname, flags); 322 323 /* 324 * Legacy open drain handling for fixed voltage regulators. 325 */ 326 if (IS_ENABLED(CONFIG_REGULATOR) && 327 of_device_is_compatible(np, "reg-fixed-voltage") && 328 of_property_read_bool(np, "gpio-open-drain")) { 329 *flags |= (OF_GPIO_SINGLE_ENDED | OF_GPIO_OPEN_DRAIN); 330 pr_info("%s uses legacy open drain flag - update the DTS if you can\n", 331 of_node_full_name(np)); 332 } 333 334 /* 335 * Legacy handling of SPI active high chip select. If we have a 336 * property named "cs-gpios" we need to inspect the child node 337 * to determine if the flags should have inverted semantics. 338 */ 339 if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") && 340 of_property_read_bool(np, "cs-gpios")) { 341 struct device_node *child; 342 u32 cs; 343 int ret; 344 345 for_each_child_of_node(np, child) { 346 ret = of_property_read_u32(child, "reg", &cs); 347 if (ret) 348 continue; 349 if (cs == index) { 350 /* 351 * SPI children have active low chip selects 352 * by default. This can be specified negatively 353 * by just omitting "spi-cs-high" in the 354 * device node, or actively by tagging on 355 * GPIO_ACTIVE_LOW as flag in the device 356 * tree. If the line is simultaneously 357 * tagged as active low in the device tree 358 * and has the "spi-cs-high" set, we get a 359 * conflict and the "spi-cs-high" flag will 360 * take precedence. 361 */ 362 bool active_high = of_property_read_bool(child, 363 "spi-cs-high"); 364 of_gpio_quirk_polarity(child, active_high, 365 flags); 366 of_node_put(child); 367 break; 368 } 369 } 370 } 371 372 /* Legacy handling of stmmac's active-low PHY reset line */ 373 if (IS_ENABLED(CONFIG_STMMAC_ETH) && 374 !strcmp(propname, "snps,reset-gpio") && 375 of_property_read_bool(np, "snps,reset-active-low")) 376 *flags |= OF_GPIO_ACTIVE_LOW; 377 } 378 379 /** 380 * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API 381 * @np: device node to get GPIO from 382 * @propname: property name containing gpio specifier(s) 383 * @index: index of the GPIO 384 * @flags: a flags pointer to fill in 385 * 386 * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno 387 * value on the error condition. If @flags is not NULL the function also fills 388 * in flags for the GPIO. 389 */ 390 static struct gpio_desc *of_get_named_gpiod_flags(const struct device_node *np, 391 const char *propname, int index, enum of_gpio_flags *flags) 392 { 393 struct of_phandle_args gpiospec; 394 struct gpio_desc *desc; 395 int ret; 396 397 ret = of_parse_phandle_with_args_map(np, propname, "gpio", index, 398 &gpiospec); 399 if (ret) { 400 pr_debug("%s: can't parse '%s' property of node '%pOF[%d]'\n", 401 __func__, propname, np, index); 402 return ERR_PTR(ret); 403 } 404 405 struct gpio_device *gdev __free(gpio_device_put) = 406 of_find_gpio_device_by_xlate(&gpiospec); 407 if (!gdev) { 408 desc = ERR_PTR(-EPROBE_DEFER); 409 goto out; 410 } 411 412 desc = of_xlate_and_get_gpiod_flags(gpio_device_get_chip(gdev), 413 &gpiospec, flags); 414 if (IS_ERR(desc)) 415 goto out; 416 417 if (flags) 418 of_gpio_flags_quirks(np, propname, flags, index); 419 420 pr_debug("%s: parsed '%s' property of node '%pOF[%d]' - status (%d)\n", 421 __func__, propname, np, index, 422 PTR_ERR_OR_ZERO(desc)); 423 424 out: 425 of_node_put(gpiospec.np); 426 427 return desc; 428 } 429 430 /** 431 * of_get_named_gpio() - Get a GPIO number to use with GPIO API 432 * @np: device node to get GPIO from 433 * @propname: Name of property containing gpio specifier(s) 434 * @index: index of the GPIO 435 * 436 * **DEPRECATED** This function is deprecated and must not be used in new code. 437 * 438 * Returns GPIO number to use with Linux generic GPIO API, or one of the errno 439 * value on the error condition. 440 */ 441 int of_get_named_gpio(const struct device_node *np, const char *propname, 442 int index) 443 { 444 struct gpio_desc *desc; 445 446 desc = of_get_named_gpiod_flags(np, propname, index, NULL); 447 448 if (IS_ERR(desc)) 449 return PTR_ERR(desc); 450 else 451 return desc_to_gpio(desc); 452 } 453 EXPORT_SYMBOL_GPL(of_get_named_gpio); 454 455 /* Converts gpio_lookup_flags into bitmask of GPIO_* values */ 456 static unsigned long of_convert_gpio_flags(enum of_gpio_flags flags) 457 { 458 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT; 459 460 if (flags & OF_GPIO_ACTIVE_LOW) 461 lflags |= GPIO_ACTIVE_LOW; 462 463 if (flags & OF_GPIO_SINGLE_ENDED) { 464 if (flags & OF_GPIO_OPEN_DRAIN) 465 lflags |= GPIO_OPEN_DRAIN; 466 else 467 lflags |= GPIO_OPEN_SOURCE; 468 } 469 470 if (flags & OF_GPIO_TRANSITORY) 471 lflags |= GPIO_TRANSITORY; 472 473 if (flags & OF_GPIO_PULL_UP) 474 lflags |= GPIO_PULL_UP; 475 476 if (flags & OF_GPIO_PULL_DOWN) 477 lflags |= GPIO_PULL_DOWN; 478 479 if (flags & OF_GPIO_PULL_DISABLE) 480 lflags |= GPIO_PULL_DISABLE; 481 482 return lflags; 483 } 484 485 static struct gpio_desc *of_find_gpio_rename(struct device_node *np, 486 const char *con_id, 487 unsigned int idx, 488 enum of_gpio_flags *of_flags) 489 { 490 static const struct of_rename_gpio { 491 const char *con_id; 492 const char *legacy_id; /* NULL - same as con_id */ 493 /* 494 * Compatible string can be set to NULL in case where 495 * matching to a particular compatible is not practical, 496 * but it should only be done for gpio names that have 497 * vendor prefix to reduce risk of false positives. 498 * Addition of such entries is strongly discouraged. 499 */ 500 const char *compatible; 501 } gpios[] = { 502 #if IS_ENABLED(CONFIG_LCD_HX8357) 503 /* Himax LCD controllers used "gpios-reset" */ 504 { "reset", "gpios-reset", "himax,hx8357" }, 505 { "reset", "gpios-reset", "himax,hx8369" }, 506 #endif 507 #if IS_ENABLED(CONFIG_MFD_ARIZONA) 508 { "wlf,reset", NULL, NULL }, 509 #endif 510 #if IS_ENABLED(CONFIG_RTC_DRV_MOXART) 511 { "rtc-data", "gpio-rtc-data", "moxa,moxart-rtc" }, 512 { "rtc-sclk", "gpio-rtc-sclk", "moxa,moxart-rtc" }, 513 { "rtc-reset", "gpio-rtc-reset", "moxa,moxart-rtc" }, 514 #endif 515 #if IS_ENABLED(CONFIG_NFC_MRVL_I2C) 516 { "reset", "reset-n-io", "marvell,nfc-i2c" }, 517 #endif 518 #if IS_ENABLED(CONFIG_NFC_MRVL_SPI) 519 { "reset", "reset-n-io", "marvell,nfc-spi" }, 520 #endif 521 #if IS_ENABLED(CONFIG_NFC_MRVL_UART) 522 { "reset", "reset-n-io", "marvell,nfc-uart" }, 523 { "reset", "reset-n-io", "mrvl,nfc-uart" }, 524 #endif 525 #if IS_ENABLED(CONFIG_PCI_LANTIQ) 526 /* MIPS Lantiq PCI */ 527 { "reset", "gpio-reset", "lantiq,pci-xway" }, 528 #endif 529 530 /* 531 * Some regulator bindings happened before we managed to 532 * establish that GPIO properties should be named 533 * "foo-gpios" so we have this special kludge for them. 534 */ 535 #if IS_ENABLED(CONFIG_REGULATOR_ARIZONA_LDO1) 536 { "wlf,ldoena", NULL, NULL }, /* Arizona */ 537 #endif 538 #if IS_ENABLED(CONFIG_REGULATOR_WM8994) 539 { "wlf,ldo1ena", NULL, NULL }, /* WM8994 */ 540 { "wlf,ldo2ena", NULL, NULL }, /* WM8994 */ 541 #endif 542 543 #if IS_ENABLED(CONFIG_SND_SOC_CS42L56) 544 { "reset", "cirrus,gpio-nreset", "cirrus,cs42l56" }, 545 #endif 546 #if IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448) 547 { "i2s1-in-sel-gpio1", NULL, "mediatek,mt2701-cs42448-machine" }, 548 { "i2s1-in-sel-gpio2", NULL, "mediatek,mt2701-cs42448-machine" }, 549 #endif 550 #if IS_ENABLED(CONFIG_SND_SOC_TLV320AIC3X) 551 { "reset", "gpio-reset", "ti,tlv320aic3x" }, 552 { "reset", "gpio-reset", "ti,tlv320aic33" }, 553 { "reset", "gpio-reset", "ti,tlv320aic3007" }, 554 { "reset", "gpio-reset", "ti,tlv320aic3104" }, 555 { "reset", "gpio-reset", "ti,tlv320aic3106" }, 556 #endif 557 #if IS_ENABLED(CONFIG_SPI_GPIO) 558 /* 559 * The SPI GPIO bindings happened before we managed to 560 * establish that GPIO properties should be named 561 * "foo-gpios" so we have this special kludge for them. 562 */ 563 { "miso", "gpio-miso", "spi-gpio" }, 564 { "mosi", "gpio-mosi", "spi-gpio" }, 565 { "sck", "gpio-sck", "spi-gpio" }, 566 #endif 567 568 /* 569 * The old Freescale bindings use simply "gpios" as name 570 * for the chip select lines rather than "cs-gpios" like 571 * all other SPI hardware. Allow this specifically for 572 * Freescale and PPC devices. 573 */ 574 #if IS_ENABLED(CONFIG_SPI_FSL_SPI) 575 { "cs", "gpios", "fsl,spi" }, 576 { "cs", "gpios", "aeroflexgaisler,spictrl" }, 577 #endif 578 #if IS_ENABLED(CONFIG_SPI_PPC4xx) 579 { "cs", "gpios", "ibm,ppc4xx-spi" }, 580 #endif 581 582 #if IS_ENABLED(CONFIG_TYPEC_FUSB302) 583 /* 584 * Fairchild FUSB302 host is using undocumented "fcs,int_n" 585 * property without the compulsory "-gpios" suffix. 586 */ 587 { "fcs,int_n", NULL, "fcs,fusb302" }, 588 #endif 589 }; 590 struct gpio_desc *desc; 591 const char *legacy_id; 592 unsigned int i; 593 594 if (!con_id) 595 return ERR_PTR(-ENOENT); 596 597 for (i = 0; i < ARRAY_SIZE(gpios); i++) { 598 if (strcmp(con_id, gpios[i].con_id)) 599 continue; 600 601 if (gpios[i].compatible && 602 !of_device_is_compatible(np, gpios[i].compatible)) 603 continue; 604 605 legacy_id = gpios[i].legacy_id ?: gpios[i].con_id; 606 desc = of_get_named_gpiod_flags(np, legacy_id, idx, of_flags); 607 if (!gpiod_not_found(desc)) { 608 pr_info("%s uses legacy gpio name '%s' instead of '%s-gpios'\n", 609 of_node_full_name(np), legacy_id, con_id); 610 return desc; 611 } 612 } 613 614 return ERR_PTR(-ENOENT); 615 } 616 617 static struct gpio_desc *of_find_mt2701_gpio(struct device_node *np, 618 const char *con_id, 619 unsigned int idx, 620 enum of_gpio_flags *of_flags) 621 { 622 struct gpio_desc *desc; 623 const char *legacy_id; 624 625 if (!IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448)) 626 return ERR_PTR(-ENOENT); 627 628 if (!of_device_is_compatible(np, "mediatek,mt2701-cs42448-machine")) 629 return ERR_PTR(-ENOENT); 630 631 if (!con_id || strcmp(con_id, "i2s1-in-sel")) 632 return ERR_PTR(-ENOENT); 633 634 if (idx == 0) 635 legacy_id = "i2s1-in-sel-gpio1"; 636 else if (idx == 1) 637 legacy_id = "i2s1-in-sel-gpio2"; 638 else 639 return ERR_PTR(-ENOENT); 640 641 desc = of_get_named_gpiod_flags(np, legacy_id, 0, of_flags); 642 if (!gpiod_not_found(desc)) 643 pr_info("%s is using legacy gpio name '%s' instead of '%s-gpios'\n", 644 of_node_full_name(np), legacy_id, con_id); 645 646 return desc; 647 } 648 649 /* 650 * Trigger sources are special, they allow us to use any GPIO as a LED trigger 651 * and have the name "trigger-sources" no matter which kind of phandle it is 652 * pointing to, whether to a GPIO, a USB host, a network PHY etc. So in this case 653 * we allow looking something up that is not named "foo-gpios". 654 */ 655 static struct gpio_desc *of_find_trigger_gpio(struct device_node *np, 656 const char *con_id, 657 unsigned int idx, 658 enum of_gpio_flags *of_flags) 659 { 660 struct gpio_desc *desc; 661 662 if (!IS_ENABLED(CONFIG_LEDS_TRIGGER_GPIO)) 663 return ERR_PTR(-ENOENT); 664 665 if (!con_id || strcmp(con_id, "trigger-sources")) 666 return ERR_PTR(-ENOENT); 667 668 desc = of_get_named_gpiod_flags(np, con_id, idx, of_flags); 669 if (!gpiod_not_found(desc)) 670 pr_debug("%s is used as a trigger\n", of_node_full_name(np)); 671 672 return desc; 673 } 674 675 676 typedef struct gpio_desc *(*of_find_gpio_quirk)(struct device_node *np, 677 const char *con_id, 678 unsigned int idx, 679 enum of_gpio_flags *of_flags); 680 static const of_find_gpio_quirk of_find_gpio_quirks[] = { 681 of_find_gpio_rename, 682 of_find_mt2701_gpio, 683 of_find_trigger_gpio, 684 NULL 685 }; 686 687 struct gpio_desc *of_find_gpio(struct device_node *np, const char *con_id, 688 unsigned int idx, unsigned long *flags) 689 { 690 char prop_name[32]; /* 32 is max size of property name */ 691 enum of_gpio_flags of_flags; 692 const of_find_gpio_quirk *q; 693 struct gpio_desc *desc; 694 unsigned int i; 695 696 /* Try GPIO property "foo-gpios" and "foo-gpio" */ 697 for (i = 0; i < gpio_suffix_count; i++) { 698 if (con_id) 699 snprintf(prop_name, sizeof(prop_name), "%s-%s", con_id, 700 gpio_suffixes[i]); 701 else 702 snprintf(prop_name, sizeof(prop_name), "%s", 703 gpio_suffixes[i]); 704 705 desc = of_get_named_gpiod_flags(np, prop_name, idx, &of_flags); 706 707 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 GPIO descriptor to use with Linux GPIO API, or one of the errno 734 * value on the error condition. 735 */ 736 static struct gpio_desc *of_parse_own_gpio(struct device_node *np, 737 struct gpio_chip *chip, 738 unsigned int idx, const char **name, 739 unsigned long *lflags, 740 enum gpiod_flags *dflags) 741 { 742 struct device_node *chip_np; 743 enum of_gpio_flags xlate_flags; 744 struct of_phandle_args gpiospec; 745 struct gpio_desc *desc; 746 unsigned int i; 747 u32 tmp; 748 int ret; 749 750 chip_np = dev_of_node(&chip->gpiodev->dev); 751 if (!chip_np) 752 return ERR_PTR(-EINVAL); 753 754 xlate_flags = 0; 755 *lflags = GPIO_LOOKUP_FLAGS_DEFAULT; 756 *dflags = GPIOD_ASIS; 757 758 ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp); 759 if (ret) 760 return ERR_PTR(ret); 761 762 gpiospec.np = chip_np; 763 gpiospec.args_count = tmp; 764 765 for (i = 0; i < tmp; i++) { 766 ret = of_property_read_u32_index(np, "gpios", idx * tmp + i, 767 &gpiospec.args[i]); 768 if (ret) 769 return ERR_PTR(ret); 770 } 771 772 desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, &xlate_flags); 773 if (IS_ERR(desc)) 774 return desc; 775 776 *lflags = of_convert_gpio_flags(xlate_flags); 777 778 if (of_property_read_bool(np, "input")) 779 *dflags |= GPIOD_IN; 780 else if (of_property_read_bool(np, "output-low")) 781 *dflags |= GPIOD_OUT_LOW; 782 else if (of_property_read_bool(np, "output-high")) 783 *dflags |= GPIOD_OUT_HIGH; 784 else { 785 pr_warn("GPIO line %d (%pOFn): no hogging state specified, bailing out\n", 786 desc_to_gpio(desc), np); 787 return ERR_PTR(-EINVAL); 788 } 789 790 if (name && of_property_read_string(np, "line-name", name)) 791 *name = np->name; 792 793 return desc; 794 } 795 796 /** 797 * of_gpiochip_add_hog - Add all hogs in a hog device node 798 * @chip: gpio chip to act on 799 * @hog: device node describing the hogs 800 * 801 * Returns error if it fails otherwise 0 on success. 802 */ 803 static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog) 804 { 805 enum gpiod_flags dflags; 806 struct gpio_desc *desc; 807 unsigned long lflags; 808 const char *name; 809 unsigned int i; 810 int ret; 811 812 for (i = 0;; i++) { 813 desc = of_parse_own_gpio(hog, chip, i, &name, &lflags, &dflags); 814 if (IS_ERR(desc)) 815 break; 816 817 ret = gpiod_hog(desc, name, lflags, dflags); 818 if (ret < 0) 819 return ret; 820 821 #ifdef CONFIG_OF_DYNAMIC 822 WRITE_ONCE(desc->hog, hog); 823 #endif 824 } 825 826 return 0; 827 } 828 829 /** 830 * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions 831 * @chip: gpio chip to act on 832 * 833 * This is only used by of_gpiochip_add to request/set GPIO initial 834 * configuration. 835 * It returns error if it fails otherwise 0 on success. 836 */ 837 static int of_gpiochip_scan_gpios(struct gpio_chip *chip) 838 { 839 struct device_node *np; 840 int ret; 841 842 for_each_available_child_of_node(dev_of_node(&chip->gpiodev->dev), np) { 843 if (!of_property_read_bool(np, "gpio-hog")) 844 continue; 845 846 ret = of_gpiochip_add_hog(chip, np); 847 if (ret < 0) { 848 of_node_put(np); 849 return ret; 850 } 851 852 of_node_set_flag(np, OF_POPULATED); 853 } 854 855 return 0; 856 } 857 858 #ifdef CONFIG_OF_DYNAMIC 859 /** 860 * of_gpiochip_remove_hog - Remove all hogs in a hog device node 861 * @chip: gpio chip to act on 862 * @hog: device node describing the hogs 863 */ 864 static void of_gpiochip_remove_hog(struct gpio_chip *chip, 865 struct device_node *hog) 866 { 867 struct gpio_desc *desc; 868 869 for_each_gpio_desc_with_flag(chip, desc, FLAG_IS_HOGGED) 870 if (READ_ONCE(desc->hog) == hog) 871 gpiochip_free_own_desc(desc); 872 } 873 874 static int of_gpiochip_match_node(struct gpio_chip *chip, const void *data) 875 { 876 return device_match_of_node(&chip->gpiodev->dev, data); 877 } 878 879 static struct gpio_device *of_find_gpio_device_by_node(struct device_node *np) 880 { 881 return gpio_device_find(np, of_gpiochip_match_node); 882 } 883 884 static int of_gpio_notify(struct notifier_block *nb, unsigned long action, 885 void *arg) 886 { 887 struct gpio_device *gdev __free(gpio_device_put) = NULL; 888 struct of_reconfig_data *rd = arg; 889 int ret; 890 891 /* 892 * This only supports adding and removing complete gpio-hog nodes. 893 * Modifying an existing gpio-hog node is not supported (except for 894 * changing its "status" property, which is treated the same as 895 * addition/removal). 896 */ 897 switch (of_reconfig_get_state_change(action, arg)) { 898 case OF_RECONFIG_CHANGE_ADD: 899 if (!of_property_read_bool(rd->dn, "gpio-hog")) 900 return NOTIFY_DONE; /* not for us */ 901 902 if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) 903 return NOTIFY_DONE; 904 905 gdev = of_find_gpio_device_by_node(rd->dn->parent); 906 if (!gdev) 907 return NOTIFY_DONE; /* not for us */ 908 909 ret = of_gpiochip_add_hog(gpio_device_get_chip(gdev), rd->dn); 910 if (ret < 0) { 911 pr_err("%s: failed to add hogs for %pOF\n", __func__, 912 rd->dn); 913 of_node_clear_flag(rd->dn, OF_POPULATED); 914 return notifier_from_errno(ret); 915 } 916 return NOTIFY_OK; 917 918 case OF_RECONFIG_CHANGE_REMOVE: 919 if (!of_node_check_flag(rd->dn, OF_POPULATED)) 920 return NOTIFY_DONE; /* already depopulated */ 921 922 gdev = of_find_gpio_device_by_node(rd->dn->parent); 923 if (!gdev) 924 return NOTIFY_DONE; /* not for us */ 925 926 of_gpiochip_remove_hog(gpio_device_get_chip(gdev), rd->dn); 927 of_node_clear_flag(rd->dn, OF_POPULATED); 928 return NOTIFY_OK; 929 } 930 931 return NOTIFY_DONE; 932 } 933 934 struct notifier_block gpio_of_notifier = { 935 .notifier_call = of_gpio_notify, 936 }; 937 #endif /* CONFIG_OF_DYNAMIC */ 938 939 /** 940 * of_gpio_simple_xlate - translate gpiospec to the GPIO number and flags 941 * @gc: pointer to the gpio_chip structure 942 * @gpiospec: GPIO specifier as found in the device tree 943 * @flags: a flags pointer to fill in 944 * 945 * This is simple translation function, suitable for the most 1:1 mapped 946 * GPIO chips. This function performs only one sanity check: whether GPIO 947 * is less than ngpios (that is specified in the gpio_chip). 948 */ 949 static int of_gpio_simple_xlate(struct gpio_chip *gc, 950 const struct of_phandle_args *gpiospec, 951 u32 *flags) 952 { 953 /* 954 * We're discouraging gpio_cells < 2, since that way you'll have to 955 * write your own xlate function (that will have to retrieve the GPIO 956 * number and the flags from a single gpio cell -- this is possible, 957 * but not recommended). 958 */ 959 if (gc->of_gpio_n_cells < 2) { 960 WARN_ON(1); 961 return -EINVAL; 962 } 963 964 if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells)) 965 return -EINVAL; 966 967 if (gpiospec->args[0] >= gc->ngpio) 968 return -EINVAL; 969 970 if (flags) 971 *flags = gpiospec->args[1]; 972 973 return gpiospec->args[0]; 974 } 975 976 #if IS_ENABLED(CONFIG_OF_GPIO_MM_GPIOCHIP) 977 #include <linux/gpio/legacy-of-mm-gpiochip.h> 978 /** 979 * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank) 980 * @np: device node of the GPIO chip 981 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure 982 * @data: driver data to store in the struct gpio_chip 983 * 984 * To use this function you should allocate and fill mm_gc with: 985 * 986 * 1) In the gpio_chip structure: 987 * - all the callbacks 988 * - of_gpio_n_cells 989 * - of_xlate callback (optional) 990 * 991 * 3) In the of_mm_gpio_chip structure: 992 * - save_regs callback (optional) 993 * 994 * If succeeded, this function will map bank's memory and will 995 * do all necessary work for you. Then you'll able to use .regs 996 * to manage GPIOs from the callbacks. 997 */ 998 int of_mm_gpiochip_add_data(struct device_node *np, 999 struct of_mm_gpio_chip *mm_gc, 1000 void *data) 1001 { 1002 int ret = -ENOMEM; 1003 struct gpio_chip *gc = &mm_gc->gc; 1004 1005 gc->label = kasprintf(GFP_KERNEL, "%pOF", np); 1006 if (!gc->label) 1007 goto err0; 1008 1009 mm_gc->regs = of_iomap(np, 0); 1010 if (!mm_gc->regs) 1011 goto err1; 1012 1013 gc->base = -1; 1014 1015 if (mm_gc->save_regs) 1016 mm_gc->save_regs(mm_gc); 1017 1018 fwnode_handle_put(mm_gc->gc.fwnode); 1019 mm_gc->gc.fwnode = fwnode_handle_get(of_fwnode_handle(np)); 1020 1021 ret = gpiochip_add_data(gc, data); 1022 if (ret) 1023 goto err2; 1024 1025 return 0; 1026 err2: 1027 of_node_put(np); 1028 iounmap(mm_gc->regs); 1029 err1: 1030 kfree(gc->label); 1031 err0: 1032 pr_err("%pOF: GPIO chip registration failed with status %d\n", np, ret); 1033 return ret; 1034 } 1035 EXPORT_SYMBOL_GPL(of_mm_gpiochip_add_data); 1036 1037 /** 1038 * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank) 1039 * @mm_gc: pointer to the of_mm_gpio_chip allocated structure 1040 */ 1041 void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc) 1042 { 1043 struct gpio_chip *gc = &mm_gc->gc; 1044 1045 gpiochip_remove(gc); 1046 iounmap(mm_gc->regs); 1047 kfree(gc->label); 1048 } 1049 EXPORT_SYMBOL_GPL(of_mm_gpiochip_remove); 1050 #endif 1051 1052 #ifdef CONFIG_PINCTRL 1053 static int of_gpiochip_add_pin_range(struct gpio_chip *chip) 1054 { 1055 struct of_phandle_args pinspec; 1056 struct pinctrl_dev *pctldev; 1057 struct device_node *np; 1058 int index = 0, ret, trim; 1059 const char *name; 1060 static const char group_names_propname[] = "gpio-ranges-group-names"; 1061 struct property *group_names; 1062 1063 np = dev_of_node(&chip->gpiodev->dev); 1064 if (!np) 1065 return 0; 1066 1067 group_names = of_find_property(np, group_names_propname, NULL); 1068 1069 for (;; index++) { 1070 ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, 1071 index, &pinspec); 1072 if (ret) 1073 break; 1074 1075 pctldev = of_pinctrl_get(pinspec.np); 1076 of_node_put(pinspec.np); 1077 if (!pctldev) 1078 return -EPROBE_DEFER; 1079 1080 /* Ignore ranges outside of this GPIO chip */ 1081 if (pinspec.args[0] >= (chip->offset + chip->ngpio)) 1082 continue; 1083 if (pinspec.args[0] + pinspec.args[2] <= chip->offset) 1084 continue; 1085 1086 if (pinspec.args[2]) { 1087 /* npins != 0: linear range */ 1088 if (group_names) { 1089 of_property_read_string_index(np, 1090 group_names_propname, 1091 index, &name); 1092 if (strlen(name)) { 1093 pr_err("%pOF: Group name of numeric GPIO ranges must be the empty string.\n", 1094 np); 1095 break; 1096 } 1097 } 1098 1099 /* Trim the range to fit this GPIO chip */ 1100 if (chip->offset > pinspec.args[0]) { 1101 trim = chip->offset - pinspec.args[0]; 1102 pinspec.args[2] -= trim; 1103 pinspec.args[1] += trim; 1104 pinspec.args[0] = 0; 1105 } else { 1106 pinspec.args[0] -= chip->offset; 1107 } 1108 if ((pinspec.args[0] + pinspec.args[2]) > chip->ngpio) 1109 pinspec.args[2] = chip->ngpio - pinspec.args[0]; 1110 1111 ret = gpiochip_add_pin_range(chip, 1112 pinctrl_dev_get_devname(pctldev), 1113 pinspec.args[0], 1114 pinspec.args[1], 1115 pinspec.args[2]); 1116 if (ret) 1117 return ret; 1118 } else { 1119 /* npins == 0: special range */ 1120 if (pinspec.args[1]) { 1121 pr_err("%pOF: Illegal gpio-range format.\n", 1122 np); 1123 break; 1124 } 1125 1126 if (!group_names) { 1127 pr_err("%pOF: GPIO group range requested but no %s property.\n", 1128 np, group_names_propname); 1129 break; 1130 } 1131 1132 ret = of_property_read_string_index(np, 1133 group_names_propname, 1134 index, &name); 1135 if (ret) 1136 break; 1137 1138 if (!strlen(name)) { 1139 pr_err("%pOF: Group name of GPIO group range cannot be the empty string.\n", 1140 np); 1141 break; 1142 } 1143 1144 ret = gpiochip_add_pingroup_range(chip, pctldev, 1145 pinspec.args[0], name); 1146 if (ret) 1147 return ret; 1148 } 1149 } 1150 1151 return 0; 1152 } 1153 1154 #else 1155 static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; } 1156 #endif 1157 1158 int of_gpiochip_add(struct gpio_chip *chip) 1159 { 1160 struct device_node *np; 1161 int ret; 1162 1163 np = dev_of_node(&chip->gpiodev->dev); 1164 if (!np) 1165 return 0; 1166 1167 if (!chip->of_xlate) { 1168 chip->of_gpio_n_cells = 2; 1169 chip->of_xlate = of_gpio_simple_xlate; 1170 } 1171 1172 if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS) 1173 return -EINVAL; 1174 1175 ret = of_gpiochip_add_pin_range(chip); 1176 if (ret) 1177 return ret; 1178 1179 of_node_get(np); 1180 1181 ret = of_gpiochip_scan_gpios(chip); 1182 if (ret) 1183 of_node_put(np); 1184 1185 return ret; 1186 } 1187 1188 void of_gpiochip_remove(struct gpio_chip *chip) 1189 { 1190 of_node_put(dev_of_node(&chip->gpiodev->dev)); 1191 } 1192