1 // SPDX-License-Identifier: GPL-2.0 2 3 #include <linux/bitmap.h> 4 #include <linux/kernel.h> 5 #include <linux/module.h> 6 #include <linux/interrupt.h> 7 #include <linux/irq.h> 8 #include <linux/spinlock.h> 9 #include <linux/list.h> 10 #include <linux/device.h> 11 #include <linux/err.h> 12 #include <linux/debugfs.h> 13 #include <linux/seq_file.h> 14 #include <linux/gpio.h> 15 #include <linux/idr.h> 16 #include <linux/slab.h> 17 #include <linux/acpi.h> 18 #include <linux/gpio/driver.h> 19 #include <linux/gpio/machine.h> 20 #include <linux/pinctrl/consumer.h> 21 #include <linux/fs.h> 22 #include <linux/compat.h> 23 #include <linux/file.h> 24 #include <uapi/linux/gpio.h> 25 26 #include "gpiolib.h" 27 #include "gpiolib-of.h" 28 #include "gpiolib-acpi.h" 29 #include "gpiolib-cdev.h" 30 #include "gpiolib-sysfs.h" 31 32 #define CREATE_TRACE_POINTS 33 #include <trace/events/gpio.h> 34 35 /* Implementation infrastructure for GPIO interfaces. 36 * 37 * The GPIO programming interface allows for inlining speed-critical 38 * get/set operations for common cases, so that access to SOC-integrated 39 * GPIOs can sometimes cost only an instruction or two per bit. 40 */ 41 42 43 /* When debugging, extend minimal trust to callers and platform code. 44 * Also emit diagnostic messages that may help initial bringup, when 45 * board setup or driver bugs are most common. 46 * 47 * Otherwise, minimize overhead in what may be bitbanging codepaths. 48 */ 49 #ifdef DEBUG 50 #define extra_checks 1 51 #else 52 #define extra_checks 0 53 #endif 54 55 /* Device and char device-related information */ 56 static DEFINE_IDA(gpio_ida); 57 static dev_t gpio_devt; 58 #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */ 59 static int gpio_bus_match(struct device *dev, struct device_driver *drv); 60 static struct bus_type gpio_bus_type = { 61 .name = "gpio", 62 .match = gpio_bus_match, 63 }; 64 65 /* 66 * Number of GPIOs to use for the fast path in set array 67 */ 68 #define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT 69 70 /* gpio_lock prevents conflicts during gpio_desc[] table updates. 71 * While any GPIO is requested, its gpio_chip is not removable; 72 * each GPIO's "requested" flag serves as a lock and refcount. 73 */ 74 DEFINE_SPINLOCK(gpio_lock); 75 76 static DEFINE_MUTEX(gpio_lookup_lock); 77 static LIST_HEAD(gpio_lookup_list); 78 LIST_HEAD(gpio_devices); 79 80 static DEFINE_MUTEX(gpio_machine_hogs_mutex); 81 static LIST_HEAD(gpio_machine_hogs); 82 83 static void gpiochip_free_hogs(struct gpio_chip *gc); 84 static int gpiochip_add_irqchip(struct gpio_chip *gc, 85 struct lock_class_key *lock_key, 86 struct lock_class_key *request_key); 87 static void gpiochip_irqchip_remove(struct gpio_chip *gc); 88 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc); 89 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc); 90 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc); 91 92 static bool gpiolib_initialized; 93 94 static inline void desc_set_label(struct gpio_desc *d, const char *label) 95 { 96 d->label = label; 97 } 98 99 /** 100 * gpio_to_desc - Convert a GPIO number to its descriptor 101 * @gpio: global GPIO number 102 * 103 * Returns: 104 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO 105 * with the given number exists in the system. 106 */ 107 struct gpio_desc *gpio_to_desc(unsigned gpio) 108 { 109 struct gpio_device *gdev; 110 unsigned long flags; 111 112 spin_lock_irqsave(&gpio_lock, flags); 113 114 list_for_each_entry(gdev, &gpio_devices, list) { 115 if (gdev->base <= gpio && 116 gdev->base + gdev->ngpio > gpio) { 117 spin_unlock_irqrestore(&gpio_lock, flags); 118 return &gdev->descs[gpio - gdev->base]; 119 } 120 } 121 122 spin_unlock_irqrestore(&gpio_lock, flags); 123 124 if (!gpio_is_valid(gpio)) 125 pr_warn("invalid GPIO %d\n", gpio); 126 127 return NULL; 128 } 129 EXPORT_SYMBOL_GPL(gpio_to_desc); 130 131 /** 132 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given 133 * hardware number for this chip 134 * @gc: GPIO chip 135 * @hwnum: hardware number of the GPIO for this chip 136 * 137 * Returns: 138 * A pointer to the GPIO descriptor or ``ERR_PTR(-EINVAL)`` if no GPIO exists 139 * in the given chip for the specified hardware number. 140 */ 141 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc, 142 unsigned int hwnum) 143 { 144 struct gpio_device *gdev = gc->gpiodev; 145 146 if (hwnum >= gdev->ngpio) 147 return ERR_PTR(-EINVAL); 148 149 return &gdev->descs[hwnum]; 150 } 151 EXPORT_SYMBOL_GPL(gpiochip_get_desc); 152 153 /** 154 * desc_to_gpio - convert a GPIO descriptor to the integer namespace 155 * @desc: GPIO descriptor 156 * 157 * This should disappear in the future but is needed since we still 158 * use GPIO numbers for error messages and sysfs nodes. 159 * 160 * Returns: 161 * The global GPIO number for the GPIO specified by its descriptor. 162 */ 163 int desc_to_gpio(const struct gpio_desc *desc) 164 { 165 return desc->gdev->base + (desc - &desc->gdev->descs[0]); 166 } 167 EXPORT_SYMBOL_GPL(desc_to_gpio); 168 169 170 /** 171 * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs 172 * @desc: descriptor to return the chip of 173 */ 174 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) 175 { 176 if (!desc || !desc->gdev) 177 return NULL; 178 return desc->gdev->chip; 179 } 180 EXPORT_SYMBOL_GPL(gpiod_to_chip); 181 182 /* dynamic allocation of GPIOs, e.g. on a hotplugged device */ 183 static int gpiochip_find_base(int ngpio) 184 { 185 struct gpio_device *gdev; 186 int base = ARCH_NR_GPIOS - ngpio; 187 188 list_for_each_entry_reverse(gdev, &gpio_devices, list) { 189 /* found a free space? */ 190 if (gdev->base + gdev->ngpio <= base) 191 break; 192 else 193 /* nope, check the space right before the chip */ 194 base = gdev->base - ngpio; 195 } 196 197 if (gpio_is_valid(base)) { 198 pr_debug("%s: found new base at %d\n", __func__, base); 199 return base; 200 } else { 201 pr_err("%s: cannot find free range\n", __func__); 202 return -ENOSPC; 203 } 204 } 205 206 /** 207 * gpiod_get_direction - return the current direction of a GPIO 208 * @desc: GPIO to get the direction of 209 * 210 * Returns 0 for output, 1 for input, or an error code in case of error. 211 * 212 * This function may sleep if gpiod_cansleep() is true. 213 */ 214 int gpiod_get_direction(struct gpio_desc *desc) 215 { 216 struct gpio_chip *gc; 217 unsigned int offset; 218 int ret; 219 220 gc = gpiod_to_chip(desc); 221 offset = gpio_chip_hwgpio(desc); 222 223 /* 224 * Open drain emulation using input mode may incorrectly report 225 * input here, fix that up. 226 */ 227 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && 228 test_bit(FLAG_IS_OUT, &desc->flags)) 229 return 0; 230 231 if (!gc->get_direction) 232 return -ENOTSUPP; 233 234 ret = gc->get_direction(gc, offset); 235 if (ret < 0) 236 return ret; 237 238 /* GPIOF_DIR_IN or other positive, otherwise GPIOF_DIR_OUT */ 239 if (ret > 0) 240 ret = 1; 241 242 assign_bit(FLAG_IS_OUT, &desc->flags, !ret); 243 244 return ret; 245 } 246 EXPORT_SYMBOL_GPL(gpiod_get_direction); 247 248 /* 249 * Add a new chip to the global chips list, keeping the list of chips sorted 250 * by range(means [base, base + ngpio - 1]) order. 251 * 252 * Return -EBUSY if the new chip overlaps with some other chip's integer 253 * space. 254 */ 255 static int gpiodev_add_to_list(struct gpio_device *gdev) 256 { 257 struct gpio_device *prev, *next; 258 259 if (list_empty(&gpio_devices)) { 260 /* initial entry in list */ 261 list_add_tail(&gdev->list, &gpio_devices); 262 return 0; 263 } 264 265 next = list_first_entry(&gpio_devices, struct gpio_device, list); 266 if (gdev->base + gdev->ngpio <= next->base) { 267 /* add before first entry */ 268 list_add(&gdev->list, &gpio_devices); 269 return 0; 270 } 271 272 prev = list_last_entry(&gpio_devices, struct gpio_device, list); 273 if (prev->base + prev->ngpio <= gdev->base) { 274 /* add behind last entry */ 275 list_add_tail(&gdev->list, &gpio_devices); 276 return 0; 277 } 278 279 list_for_each_entry_safe(prev, next, &gpio_devices, list) { 280 /* at the end of the list */ 281 if (&next->list == &gpio_devices) 282 break; 283 284 /* add between prev and next */ 285 if (prev->base + prev->ngpio <= gdev->base 286 && gdev->base + gdev->ngpio <= next->base) { 287 list_add(&gdev->list, &prev->list); 288 return 0; 289 } 290 } 291 292 dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n"); 293 return -EBUSY; 294 } 295 296 /* 297 * Convert a GPIO name to its descriptor 298 * Note that there is no guarantee that GPIO names are globally unique! 299 * Hence this function will return, if it exists, a reference to the first GPIO 300 * line found that matches the given name. 301 */ 302 static struct gpio_desc *gpio_name_to_desc(const char * const name) 303 { 304 struct gpio_device *gdev; 305 unsigned long flags; 306 307 if (!name) 308 return NULL; 309 310 spin_lock_irqsave(&gpio_lock, flags); 311 312 list_for_each_entry(gdev, &gpio_devices, list) { 313 int i; 314 315 for (i = 0; i != gdev->ngpio; ++i) { 316 struct gpio_desc *desc = &gdev->descs[i]; 317 318 if (!desc->name) 319 continue; 320 321 if (!strcmp(desc->name, name)) { 322 spin_unlock_irqrestore(&gpio_lock, flags); 323 return desc; 324 } 325 } 326 } 327 328 spin_unlock_irqrestore(&gpio_lock, flags); 329 330 return NULL; 331 } 332 333 /* 334 * Take the names from gc->names and assign them to their GPIO descriptors. 335 * Warn if a name is already used for a GPIO line on a different GPIO chip. 336 * 337 * Note that: 338 * 1. Non-unique names are still accepted, 339 * 2. Name collisions within the same GPIO chip are not reported. 340 */ 341 static int gpiochip_set_desc_names(struct gpio_chip *gc) 342 { 343 struct gpio_device *gdev = gc->gpiodev; 344 int i; 345 346 /* First check all names if they are unique */ 347 for (i = 0; i != gc->ngpio; ++i) { 348 struct gpio_desc *gpio; 349 350 gpio = gpio_name_to_desc(gc->names[i]); 351 if (gpio) 352 dev_warn(&gdev->dev, 353 "Detected name collision for GPIO name '%s'\n", 354 gc->names[i]); 355 } 356 357 /* Then add all names to the GPIO descriptors */ 358 for (i = 0; i != gc->ngpio; ++i) 359 gdev->descs[i].name = gc->names[i]; 360 361 return 0; 362 } 363 364 /* 365 * devprop_gpiochip_set_names - Set GPIO line names using device properties 366 * @chip: GPIO chip whose lines should be named, if possible 367 * 368 * Looks for device property "gpio-line-names" and if it exists assigns 369 * GPIO line names for the chip. The memory allocated for the assigned 370 * names belong to the underlying firmware node and should not be released 371 * by the caller. 372 */ 373 static int devprop_gpiochip_set_names(struct gpio_chip *chip) 374 { 375 struct gpio_device *gdev = chip->gpiodev; 376 struct fwnode_handle *fwnode = dev_fwnode(&gdev->dev); 377 const char **names; 378 int ret, i; 379 int count; 380 381 count = fwnode_property_string_array_count(fwnode, "gpio-line-names"); 382 if (count < 0) 383 return 0; 384 385 /* 386 * When offset is set in the driver side we assume the driver internally 387 * is using more than one gpiochip per the same device. We have to stop 388 * setting friendly names if the specified ones with 'gpio-line-names' 389 * are less than the offset in the device itself. This means all the 390 * lines are not present for every single pin within all the internal 391 * gpiochips. 392 */ 393 if (count <= chip->offset) { 394 dev_warn(&gdev->dev, "gpio-line-names too short (length %d), cannot map names for the gpiochip at offset %u\n", 395 count, chip->offset); 396 return 0; 397 } 398 399 names = kcalloc(count, sizeof(*names), GFP_KERNEL); 400 if (!names) 401 return -ENOMEM; 402 403 ret = fwnode_property_read_string_array(fwnode, "gpio-line-names", 404 names, count); 405 if (ret < 0) { 406 dev_warn(&gdev->dev, "failed to read GPIO line names\n"); 407 kfree(names); 408 return ret; 409 } 410 411 /* 412 * When more that one gpiochip per device is used, 'count' can 413 * contain at most number gpiochips x chip->ngpio. We have to 414 * correctly distribute all defined lines taking into account 415 * chip->offset as starting point from where we will assign 416 * the names to pins from the 'names' array. Since property 417 * 'gpio-line-names' cannot contains gaps, we have to be sure 418 * we only assign those pins that really exists since chip->ngpio 419 * can be different of the chip->offset. 420 */ 421 count = (count > chip->offset) ? count - chip->offset : count; 422 if (count > chip->ngpio) 423 count = chip->ngpio; 424 425 for (i = 0; i < count; i++) { 426 /* 427 * Allow overriding "fixed" names provided by the GPIO 428 * provider. The "fixed" names are more often than not 429 * generic and less informative than the names given in 430 * device properties. 431 */ 432 if (names[chip->offset + i] && names[chip->offset + i][0]) 433 gdev->descs[i].name = names[chip->offset + i]; 434 } 435 436 kfree(names); 437 438 return 0; 439 } 440 441 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *gc) 442 { 443 unsigned long *p; 444 445 p = bitmap_alloc(gc->ngpio, GFP_KERNEL); 446 if (!p) 447 return NULL; 448 449 /* Assume by default all GPIOs are valid */ 450 bitmap_fill(p, gc->ngpio); 451 452 return p; 453 } 454 455 static int gpiochip_alloc_valid_mask(struct gpio_chip *gc) 456 { 457 if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask)) 458 return 0; 459 460 gc->valid_mask = gpiochip_allocate_mask(gc); 461 if (!gc->valid_mask) 462 return -ENOMEM; 463 464 return 0; 465 } 466 467 static int gpiochip_init_valid_mask(struct gpio_chip *gc) 468 { 469 if (gc->init_valid_mask) 470 return gc->init_valid_mask(gc, 471 gc->valid_mask, 472 gc->ngpio); 473 474 return 0; 475 } 476 477 static void gpiochip_free_valid_mask(struct gpio_chip *gc) 478 { 479 bitmap_free(gc->valid_mask); 480 gc->valid_mask = NULL; 481 } 482 483 static int gpiochip_add_pin_ranges(struct gpio_chip *gc) 484 { 485 if (gc->add_pin_ranges) 486 return gc->add_pin_ranges(gc); 487 488 return 0; 489 } 490 491 bool gpiochip_line_is_valid(const struct gpio_chip *gc, 492 unsigned int offset) 493 { 494 /* No mask means all valid */ 495 if (likely(!gc->valid_mask)) 496 return true; 497 return test_bit(offset, gc->valid_mask); 498 } 499 EXPORT_SYMBOL_GPL(gpiochip_line_is_valid); 500 501 static void gpiodevice_release(struct device *dev) 502 { 503 struct gpio_device *gdev = container_of(dev, struct gpio_device, dev); 504 unsigned long flags; 505 506 spin_lock_irqsave(&gpio_lock, flags); 507 list_del(&gdev->list); 508 spin_unlock_irqrestore(&gpio_lock, flags); 509 510 ida_free(&gpio_ida, gdev->id); 511 kfree_const(gdev->label); 512 kfree(gdev->descs); 513 kfree(gdev); 514 } 515 516 #ifdef CONFIG_GPIO_CDEV 517 #define gcdev_register(gdev, devt) gpiolib_cdev_register((gdev), (devt)) 518 #define gcdev_unregister(gdev) gpiolib_cdev_unregister((gdev)) 519 #else 520 /* 521 * gpiolib_cdev_register() indirectly calls device_add(), which is still 522 * required even when cdev is not selected. 523 */ 524 #define gcdev_register(gdev, devt) device_add(&(gdev)->dev) 525 #define gcdev_unregister(gdev) device_del(&(gdev)->dev) 526 #endif 527 528 static int gpiochip_setup_dev(struct gpio_device *gdev) 529 { 530 int ret; 531 532 ret = gcdev_register(gdev, gpio_devt); 533 if (ret) 534 return ret; 535 536 ret = gpiochip_sysfs_register(gdev); 537 if (ret) 538 goto err_remove_device; 539 540 /* From this point, the .release() function cleans up gpio_device */ 541 gdev->dev.release = gpiodevice_release; 542 dev_dbg(&gdev->dev, "registered GPIOs %d to %d on %s\n", gdev->base, 543 gdev->base + gdev->ngpio - 1, gdev->chip->label ? : "generic"); 544 545 return 0; 546 547 err_remove_device: 548 gcdev_unregister(gdev); 549 return ret; 550 } 551 552 static void gpiochip_machine_hog(struct gpio_chip *gc, struct gpiod_hog *hog) 553 { 554 struct gpio_desc *desc; 555 int rv; 556 557 desc = gpiochip_get_desc(gc, hog->chip_hwnum); 558 if (IS_ERR(desc)) { 559 chip_err(gc, "%s: unable to get GPIO desc: %ld\n", __func__, 560 PTR_ERR(desc)); 561 return; 562 } 563 564 if (test_bit(FLAG_IS_HOGGED, &desc->flags)) 565 return; 566 567 rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags); 568 if (rv) 569 gpiod_err(desc, "%s: unable to hog GPIO line (%s:%u): %d\n", 570 __func__, gc->label, hog->chip_hwnum, rv); 571 } 572 573 static void machine_gpiochip_add(struct gpio_chip *gc) 574 { 575 struct gpiod_hog *hog; 576 577 mutex_lock(&gpio_machine_hogs_mutex); 578 579 list_for_each_entry(hog, &gpio_machine_hogs, list) { 580 if (!strcmp(gc->label, hog->chip_label)) 581 gpiochip_machine_hog(gc, hog); 582 } 583 584 mutex_unlock(&gpio_machine_hogs_mutex); 585 } 586 587 static void gpiochip_setup_devs(void) 588 { 589 struct gpio_device *gdev; 590 int ret; 591 592 list_for_each_entry(gdev, &gpio_devices, list) { 593 ret = gpiochip_setup_dev(gdev); 594 if (ret) 595 dev_err(&gdev->dev, 596 "Failed to initialize gpio device (%d)\n", ret); 597 } 598 } 599 600 int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, 601 struct lock_class_key *lock_key, 602 struct lock_class_key *request_key) 603 { 604 struct fwnode_handle *fwnode = NULL; 605 struct gpio_device *gdev; 606 unsigned long flags; 607 int base = gc->base; 608 unsigned int i; 609 int ret = 0; 610 u32 ngpios; 611 612 if (gc->fwnode) 613 fwnode = gc->fwnode; 614 else if (gc->parent) 615 fwnode = dev_fwnode(gc->parent); 616 617 /* 618 * First: allocate and populate the internal stat container, and 619 * set up the struct device. 620 */ 621 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL); 622 if (!gdev) 623 return -ENOMEM; 624 gdev->dev.bus = &gpio_bus_type; 625 gdev->dev.parent = gc->parent; 626 gdev->chip = gc; 627 gc->gpiodev = gdev; 628 629 of_gpio_dev_init(gc, gdev); 630 acpi_gpio_dev_init(gc, gdev); 631 632 /* 633 * Assign fwnode depending on the result of the previous calls, 634 * if none of them succeed, assign it to the parent's one. 635 */ 636 gdev->dev.fwnode = dev_fwnode(&gdev->dev) ?: fwnode; 637 638 gdev->id = ida_alloc(&gpio_ida, GFP_KERNEL); 639 if (gdev->id < 0) { 640 ret = gdev->id; 641 goto err_free_gdev; 642 } 643 644 ret = dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id); 645 if (ret) 646 goto err_free_ida; 647 648 device_initialize(&gdev->dev); 649 if (gc->parent && gc->parent->driver) 650 gdev->owner = gc->parent->driver->owner; 651 else if (gc->owner) 652 /* TODO: remove chip->owner */ 653 gdev->owner = gc->owner; 654 else 655 gdev->owner = THIS_MODULE; 656 657 gdev->descs = kcalloc(gc->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL); 658 if (!gdev->descs) { 659 ret = -ENOMEM; 660 goto err_free_dev_name; 661 } 662 663 /* 664 * Try the device properties if the driver didn't supply the number 665 * of GPIO lines. 666 */ 667 if (gc->ngpio == 0) { 668 ret = device_property_read_u32(&gdev->dev, "ngpios", &ngpios); 669 if (ret == -ENODATA) 670 /* 671 * -ENODATA means that there is no property found and 672 * we want to issue the error message to the user. 673 * Besides that, we want to return different error code 674 * to state that supplied value is not valid. 675 */ 676 ngpios = 0; 677 else if (ret) 678 goto err_free_descs; 679 680 gc->ngpio = ngpios; 681 } 682 683 if (gc->ngpio == 0) { 684 chip_err(gc, "tried to insert a GPIO chip with zero lines\n"); 685 ret = -EINVAL; 686 goto err_free_descs; 687 } 688 689 if (gc->ngpio > FASTPATH_NGPIO) 690 chip_warn(gc, "line cnt %u is greater than fast path cnt %u\n", 691 gc->ngpio, FASTPATH_NGPIO); 692 693 gdev->label = kstrdup_const(gc->label ?: "unknown", GFP_KERNEL); 694 if (!gdev->label) { 695 ret = -ENOMEM; 696 goto err_free_descs; 697 } 698 699 gdev->ngpio = gc->ngpio; 700 gdev->data = data; 701 702 spin_lock_irqsave(&gpio_lock, flags); 703 704 /* 705 * TODO: this allocates a Linux GPIO number base in the global 706 * GPIO numberspace for this chip. In the long run we want to 707 * get *rid* of this numberspace and use only descriptors, but 708 * it may be a pipe dream. It will not happen before we get rid 709 * of the sysfs interface anyways. 710 */ 711 if (base < 0) { 712 base = gpiochip_find_base(gc->ngpio); 713 if (base < 0) { 714 ret = base; 715 spin_unlock_irqrestore(&gpio_lock, flags); 716 goto err_free_label; 717 } 718 /* 719 * TODO: it should not be necessary to reflect the assigned 720 * base outside of the GPIO subsystem. Go over drivers and 721 * see if anyone makes use of this, else drop this and assign 722 * a poison instead. 723 */ 724 gc->base = base; 725 } 726 gdev->base = base; 727 728 ret = gpiodev_add_to_list(gdev); 729 if (ret) { 730 spin_unlock_irqrestore(&gpio_lock, flags); 731 goto err_free_label; 732 } 733 734 for (i = 0; i < gc->ngpio; i++) 735 gdev->descs[i].gdev = gdev; 736 737 spin_unlock_irqrestore(&gpio_lock, flags); 738 739 BLOCKING_INIT_NOTIFIER_HEAD(&gdev->notifier); 740 741 #ifdef CONFIG_PINCTRL 742 INIT_LIST_HEAD(&gdev->pin_ranges); 743 #endif 744 745 if (gc->names) { 746 ret = gpiochip_set_desc_names(gc); 747 if (ret) 748 goto err_remove_from_list; 749 } 750 ret = devprop_gpiochip_set_names(gc); 751 if (ret) 752 goto err_remove_from_list; 753 754 ret = gpiochip_alloc_valid_mask(gc); 755 if (ret) 756 goto err_remove_from_list; 757 758 ret = of_gpiochip_add(gc); 759 if (ret) 760 goto err_free_gpiochip_mask; 761 762 ret = gpiochip_init_valid_mask(gc); 763 if (ret) 764 goto err_remove_of_chip; 765 766 for (i = 0; i < gc->ngpio; i++) { 767 struct gpio_desc *desc = &gdev->descs[i]; 768 769 if (gc->get_direction && gpiochip_line_is_valid(gc, i)) { 770 assign_bit(FLAG_IS_OUT, 771 &desc->flags, !gc->get_direction(gc, i)); 772 } else { 773 assign_bit(FLAG_IS_OUT, 774 &desc->flags, !gc->direction_input); 775 } 776 } 777 778 ret = gpiochip_add_pin_ranges(gc); 779 if (ret) 780 goto err_remove_of_chip; 781 782 acpi_gpiochip_add(gc); 783 784 machine_gpiochip_add(gc); 785 786 ret = gpiochip_irqchip_init_valid_mask(gc); 787 if (ret) 788 goto err_remove_acpi_chip; 789 790 ret = gpiochip_irqchip_init_hw(gc); 791 if (ret) 792 goto err_remove_acpi_chip; 793 794 ret = gpiochip_add_irqchip(gc, lock_key, request_key); 795 if (ret) 796 goto err_remove_irqchip_mask; 797 798 /* 799 * By first adding the chardev, and then adding the device, 800 * we get a device node entry in sysfs under 801 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for 802 * coldplug of device nodes and other udev business. 803 * We can do this only if gpiolib has been initialized. 804 * Otherwise, defer until later. 805 */ 806 if (gpiolib_initialized) { 807 ret = gpiochip_setup_dev(gdev); 808 if (ret) 809 goto err_remove_irqchip; 810 } 811 return 0; 812 813 err_remove_irqchip: 814 gpiochip_irqchip_remove(gc); 815 err_remove_irqchip_mask: 816 gpiochip_irqchip_free_valid_mask(gc); 817 err_remove_acpi_chip: 818 acpi_gpiochip_remove(gc); 819 err_remove_of_chip: 820 gpiochip_free_hogs(gc); 821 of_gpiochip_remove(gc); 822 err_free_gpiochip_mask: 823 gpiochip_remove_pin_ranges(gc); 824 gpiochip_free_valid_mask(gc); 825 err_remove_from_list: 826 spin_lock_irqsave(&gpio_lock, flags); 827 list_del(&gdev->list); 828 spin_unlock_irqrestore(&gpio_lock, flags); 829 err_free_label: 830 kfree_const(gdev->label); 831 err_free_descs: 832 kfree(gdev->descs); 833 err_free_dev_name: 834 kfree(dev_name(&gdev->dev)); 835 err_free_ida: 836 ida_free(&gpio_ida, gdev->id); 837 err_free_gdev: 838 /* failures here can mean systems won't boot... */ 839 if (ret != -EPROBE_DEFER) { 840 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__, 841 gdev->base, gdev->base + gdev->ngpio - 1, 842 gc->label ? : "generic", ret); 843 } 844 kfree(gdev); 845 return ret; 846 } 847 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key); 848 849 /** 850 * gpiochip_get_data() - get per-subdriver data for the chip 851 * @gc: GPIO chip 852 * 853 * Returns: 854 * The per-subdriver data for the chip. 855 */ 856 void *gpiochip_get_data(struct gpio_chip *gc) 857 { 858 return gc->gpiodev->data; 859 } 860 EXPORT_SYMBOL_GPL(gpiochip_get_data); 861 862 /** 863 * gpiochip_remove() - unregister a gpio_chip 864 * @gc: the chip to unregister 865 * 866 * A gpio_chip with any GPIOs still requested may not be removed. 867 */ 868 void gpiochip_remove(struct gpio_chip *gc) 869 { 870 struct gpio_device *gdev = gc->gpiodev; 871 unsigned long flags; 872 unsigned int i; 873 874 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */ 875 gpiochip_sysfs_unregister(gdev); 876 gpiochip_free_hogs(gc); 877 /* Numb the device, cancelling all outstanding operations */ 878 gdev->chip = NULL; 879 gpiochip_irqchip_remove(gc); 880 acpi_gpiochip_remove(gc); 881 of_gpiochip_remove(gc); 882 gpiochip_remove_pin_ranges(gc); 883 gpiochip_free_valid_mask(gc); 884 /* 885 * We accept no more calls into the driver from this point, so 886 * NULL the driver data pointer 887 */ 888 gdev->data = NULL; 889 890 spin_lock_irqsave(&gpio_lock, flags); 891 for (i = 0; i < gdev->ngpio; i++) { 892 if (gpiochip_is_requested(gc, i)) 893 break; 894 } 895 spin_unlock_irqrestore(&gpio_lock, flags); 896 897 if (i != gdev->ngpio) 898 dev_crit(&gdev->dev, 899 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n"); 900 901 /* 902 * The gpiochip side puts its use of the device to rest here: 903 * if there are no userspace clients, the chardev and device will 904 * be removed, else it will be dangling until the last user is 905 * gone. 906 */ 907 gcdev_unregister(gdev); 908 put_device(&gdev->dev); 909 } 910 EXPORT_SYMBOL_GPL(gpiochip_remove); 911 912 /** 913 * gpiochip_find() - iterator for locating a specific gpio_chip 914 * @data: data to pass to match function 915 * @match: Callback function to check gpio_chip 916 * 917 * Similar to bus_find_device. It returns a reference to a gpio_chip as 918 * determined by a user supplied @match callback. The callback should return 919 * 0 if the device doesn't match and non-zero if it does. If the callback is 920 * non-zero, this function will return to the caller and not iterate over any 921 * more gpio_chips. 922 */ 923 struct gpio_chip *gpiochip_find(void *data, 924 int (*match)(struct gpio_chip *gc, 925 void *data)) 926 { 927 struct gpio_device *gdev; 928 struct gpio_chip *gc = NULL; 929 unsigned long flags; 930 931 spin_lock_irqsave(&gpio_lock, flags); 932 list_for_each_entry(gdev, &gpio_devices, list) 933 if (gdev->chip && match(gdev->chip, data)) { 934 gc = gdev->chip; 935 break; 936 } 937 938 spin_unlock_irqrestore(&gpio_lock, flags); 939 940 return gc; 941 } 942 EXPORT_SYMBOL_GPL(gpiochip_find); 943 944 static int gpiochip_match_name(struct gpio_chip *gc, void *data) 945 { 946 const char *name = data; 947 948 return !strcmp(gc->label, name); 949 } 950 951 static struct gpio_chip *find_chip_by_name(const char *name) 952 { 953 return gpiochip_find((void *)name, gpiochip_match_name); 954 } 955 956 #ifdef CONFIG_GPIOLIB_IRQCHIP 957 958 /* 959 * The following is irqchip helper code for gpiochips. 960 */ 961 962 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc) 963 { 964 struct gpio_irq_chip *girq = &gc->irq; 965 966 if (!girq->init_hw) 967 return 0; 968 969 return girq->init_hw(gc); 970 } 971 972 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc) 973 { 974 struct gpio_irq_chip *girq = &gc->irq; 975 976 if (!girq->init_valid_mask) 977 return 0; 978 979 girq->valid_mask = gpiochip_allocate_mask(gc); 980 if (!girq->valid_mask) 981 return -ENOMEM; 982 983 girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio); 984 985 return 0; 986 } 987 988 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc) 989 { 990 bitmap_free(gc->irq.valid_mask); 991 gc->irq.valid_mask = NULL; 992 } 993 994 bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gc, 995 unsigned int offset) 996 { 997 if (!gpiochip_line_is_valid(gc, offset)) 998 return false; 999 /* No mask means all valid */ 1000 if (likely(!gc->irq.valid_mask)) 1001 return true; 1002 return test_bit(offset, gc->irq.valid_mask); 1003 } 1004 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid); 1005 1006 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY 1007 1008 /** 1009 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip 1010 * to a gpiochip 1011 * @gc: the gpiochip to set the irqchip hierarchical handler to 1012 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt 1013 * will then percolate up to the parent 1014 */ 1015 static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc, 1016 struct irq_chip *irqchip) 1017 { 1018 /* DT will deal with mapping each IRQ as we go along */ 1019 if (is_of_node(gc->irq.fwnode)) 1020 return; 1021 1022 /* 1023 * This is for legacy and boardfile "irqchip" fwnodes: allocate 1024 * irqs upfront instead of dynamically since we don't have the 1025 * dynamic type of allocation that hardware description languages 1026 * provide. Once all GPIO drivers using board files are gone from 1027 * the kernel we can delete this code, but for a transitional period 1028 * it is necessary to keep this around. 1029 */ 1030 if (is_fwnode_irqchip(gc->irq.fwnode)) { 1031 int i; 1032 int ret; 1033 1034 for (i = 0; i < gc->ngpio; i++) { 1035 struct irq_fwspec fwspec; 1036 unsigned int parent_hwirq; 1037 unsigned int parent_type; 1038 struct gpio_irq_chip *girq = &gc->irq; 1039 1040 /* 1041 * We call the child to parent translation function 1042 * only to check if the child IRQ is valid or not. 1043 * Just pick the rising edge type here as that is what 1044 * we likely need to support. 1045 */ 1046 ret = girq->child_to_parent_hwirq(gc, i, 1047 IRQ_TYPE_EDGE_RISING, 1048 &parent_hwirq, 1049 &parent_type); 1050 if (ret) { 1051 chip_err(gc, "skip set-up on hwirq %d\n", 1052 i); 1053 continue; 1054 } 1055 1056 fwspec.fwnode = gc->irq.fwnode; 1057 /* This is the hwirq for the GPIO line side of things */ 1058 fwspec.param[0] = girq->child_offset_to_irq(gc, i); 1059 /* Just pick something */ 1060 fwspec.param[1] = IRQ_TYPE_EDGE_RISING; 1061 fwspec.param_count = 2; 1062 ret = __irq_domain_alloc_irqs(gc->irq.domain, 1063 /* just pick something */ 1064 -1, 1065 1, 1066 NUMA_NO_NODE, 1067 &fwspec, 1068 false, 1069 NULL); 1070 if (ret < 0) { 1071 chip_err(gc, 1072 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n", 1073 i, parent_hwirq, 1074 ret); 1075 } 1076 } 1077 } 1078 1079 chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__); 1080 1081 return; 1082 } 1083 1084 static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d, 1085 struct irq_fwspec *fwspec, 1086 unsigned long *hwirq, 1087 unsigned int *type) 1088 { 1089 /* We support standard DT translation */ 1090 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) { 1091 return irq_domain_translate_twocell(d, fwspec, hwirq, type); 1092 } 1093 1094 /* This is for board files and others not using DT */ 1095 if (is_fwnode_irqchip(fwspec->fwnode)) { 1096 int ret; 1097 1098 ret = irq_domain_translate_twocell(d, fwspec, hwirq, type); 1099 if (ret) 1100 return ret; 1101 WARN_ON(*type == IRQ_TYPE_NONE); 1102 return 0; 1103 } 1104 return -EINVAL; 1105 } 1106 1107 static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d, 1108 unsigned int irq, 1109 unsigned int nr_irqs, 1110 void *data) 1111 { 1112 struct gpio_chip *gc = d->host_data; 1113 irq_hw_number_t hwirq; 1114 unsigned int type = IRQ_TYPE_NONE; 1115 struct irq_fwspec *fwspec = data; 1116 void *parent_arg; 1117 unsigned int parent_hwirq; 1118 unsigned int parent_type; 1119 struct gpio_irq_chip *girq = &gc->irq; 1120 int ret; 1121 1122 /* 1123 * The nr_irqs parameter is always one except for PCI multi-MSI 1124 * so this should not happen. 1125 */ 1126 WARN_ON(nr_irqs != 1); 1127 1128 ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type); 1129 if (ret) 1130 return ret; 1131 1132 chip_dbg(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq); 1133 1134 ret = girq->child_to_parent_hwirq(gc, hwirq, type, 1135 &parent_hwirq, &parent_type); 1136 if (ret) { 1137 chip_err(gc, "can't look up hwirq %lu\n", hwirq); 1138 return ret; 1139 } 1140 chip_dbg(gc, "found parent hwirq %u\n", parent_hwirq); 1141 1142 /* 1143 * We set handle_bad_irq because the .set_type() should 1144 * always be invoked and set the right type of handler. 1145 */ 1146 irq_domain_set_info(d, 1147 irq, 1148 hwirq, 1149 gc->irq.chip, 1150 gc, 1151 girq->handler, 1152 NULL, NULL); 1153 irq_set_probe(irq); 1154 1155 /* This parent only handles asserted level IRQs */ 1156 parent_arg = girq->populate_parent_alloc_arg(gc, parent_hwirq, parent_type); 1157 if (!parent_arg) 1158 return -ENOMEM; 1159 1160 chip_dbg(gc, "alloc_irqs_parent for %d parent hwirq %d\n", 1161 irq, parent_hwirq); 1162 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key); 1163 ret = irq_domain_alloc_irqs_parent(d, irq, 1, parent_arg); 1164 /* 1165 * If the parent irqdomain is msi, the interrupts have already 1166 * been allocated, so the EEXIST is good. 1167 */ 1168 if (irq_domain_is_msi(d->parent) && (ret == -EEXIST)) 1169 ret = 0; 1170 if (ret) 1171 chip_err(gc, 1172 "failed to allocate parent hwirq %d for hwirq %lu\n", 1173 parent_hwirq, hwirq); 1174 1175 kfree(parent_arg); 1176 return ret; 1177 } 1178 1179 static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *gc, 1180 unsigned int offset) 1181 { 1182 return offset; 1183 } 1184 1185 static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops) 1186 { 1187 ops->activate = gpiochip_irq_domain_activate; 1188 ops->deactivate = gpiochip_irq_domain_deactivate; 1189 ops->alloc = gpiochip_hierarchy_irq_domain_alloc; 1190 ops->free = irq_domain_free_irqs_common; 1191 1192 /* 1193 * We only allow overriding the translate() function for 1194 * hierarchical chips, and this should only be done if the user 1195 * really need something other than 1:1 translation. 1196 */ 1197 if (!ops->translate) 1198 ops->translate = gpiochip_hierarchy_irq_domain_translate; 1199 } 1200 1201 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc) 1202 { 1203 if (!gc->irq.child_to_parent_hwirq || 1204 !gc->irq.fwnode) { 1205 chip_err(gc, "missing irqdomain vital data\n"); 1206 return -EINVAL; 1207 } 1208 1209 if (!gc->irq.child_offset_to_irq) 1210 gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop; 1211 1212 if (!gc->irq.populate_parent_alloc_arg) 1213 gc->irq.populate_parent_alloc_arg = 1214 gpiochip_populate_parent_fwspec_twocell; 1215 1216 gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops); 1217 1218 gc->irq.domain = irq_domain_create_hierarchy( 1219 gc->irq.parent_domain, 1220 0, 1221 gc->ngpio, 1222 gc->irq.fwnode, 1223 &gc->irq.child_irq_domain_ops, 1224 gc); 1225 1226 if (!gc->irq.domain) 1227 return -ENOMEM; 1228 1229 gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip); 1230 1231 return 0; 1232 } 1233 1234 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc) 1235 { 1236 return !!gc->irq.parent_domain; 1237 } 1238 1239 void *gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *gc, 1240 unsigned int parent_hwirq, 1241 unsigned int parent_type) 1242 { 1243 struct irq_fwspec *fwspec; 1244 1245 fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL); 1246 if (!fwspec) 1247 return NULL; 1248 1249 fwspec->fwnode = gc->irq.parent_domain->fwnode; 1250 fwspec->param_count = 2; 1251 fwspec->param[0] = parent_hwirq; 1252 fwspec->param[1] = parent_type; 1253 1254 return fwspec; 1255 } 1256 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell); 1257 1258 void *gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *gc, 1259 unsigned int parent_hwirq, 1260 unsigned int parent_type) 1261 { 1262 struct irq_fwspec *fwspec; 1263 1264 fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL); 1265 if (!fwspec) 1266 return NULL; 1267 1268 fwspec->fwnode = gc->irq.parent_domain->fwnode; 1269 fwspec->param_count = 4; 1270 fwspec->param[0] = 0; 1271 fwspec->param[1] = parent_hwirq; 1272 fwspec->param[2] = 0; 1273 fwspec->param[3] = parent_type; 1274 1275 return fwspec; 1276 } 1277 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell); 1278 1279 #else 1280 1281 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc) 1282 { 1283 return -EINVAL; 1284 } 1285 1286 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc) 1287 { 1288 return false; 1289 } 1290 1291 #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */ 1292 1293 /** 1294 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip 1295 * @d: the irqdomain used by this irqchip 1296 * @irq: the global irq number used by this GPIO irqchip irq 1297 * @hwirq: the local IRQ/GPIO line offset on this gpiochip 1298 * 1299 * This function will set up the mapping for a certain IRQ line on a 1300 * gpiochip by assigning the gpiochip as chip data, and using the irqchip 1301 * stored inside the gpiochip. 1302 */ 1303 int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, 1304 irq_hw_number_t hwirq) 1305 { 1306 struct gpio_chip *gc = d->host_data; 1307 int ret = 0; 1308 1309 if (!gpiochip_irqchip_irq_valid(gc, hwirq)) 1310 return -ENXIO; 1311 1312 irq_set_chip_data(irq, gc); 1313 /* 1314 * This lock class tells lockdep that GPIO irqs are in a different 1315 * category than their parents, so it won't report false recursion. 1316 */ 1317 irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key); 1318 irq_set_chip_and_handler(irq, gc->irq.chip, gc->irq.handler); 1319 /* Chips that use nested thread handlers have them marked */ 1320 if (gc->irq.threaded) 1321 irq_set_nested_thread(irq, 1); 1322 irq_set_noprobe(irq); 1323 1324 if (gc->irq.num_parents == 1) 1325 ret = irq_set_parent(irq, gc->irq.parents[0]); 1326 else if (gc->irq.map) 1327 ret = irq_set_parent(irq, gc->irq.map[hwirq]); 1328 1329 if (ret < 0) 1330 return ret; 1331 1332 /* 1333 * No set-up of the hardware will happen if IRQ_TYPE_NONE 1334 * is passed as default type. 1335 */ 1336 if (gc->irq.default_type != IRQ_TYPE_NONE) 1337 irq_set_irq_type(irq, gc->irq.default_type); 1338 1339 return 0; 1340 } 1341 EXPORT_SYMBOL_GPL(gpiochip_irq_map); 1342 1343 void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq) 1344 { 1345 struct gpio_chip *gc = d->host_data; 1346 1347 if (gc->irq.threaded) 1348 irq_set_nested_thread(irq, 0); 1349 irq_set_chip_and_handler(irq, NULL, NULL); 1350 irq_set_chip_data(irq, NULL); 1351 } 1352 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap); 1353 1354 static const struct irq_domain_ops gpiochip_domain_ops = { 1355 .map = gpiochip_irq_map, 1356 .unmap = gpiochip_irq_unmap, 1357 /* Virtually all GPIO irqchips are twocell:ed */ 1358 .xlate = irq_domain_xlate_twocell, 1359 }; 1360 1361 /* 1362 * TODO: move these activate/deactivate in under the hierarchicial 1363 * irqchip implementation as static once SPMI and SSBI (all external 1364 * users) are phased over. 1365 */ 1366 /** 1367 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ 1368 * @domain: The IRQ domain used by this IRQ chip 1369 * @data: Outermost irq_data associated with the IRQ 1370 * @reserve: If set, only reserve an interrupt vector instead of assigning one 1371 * 1372 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be 1373 * used as the activate function for the &struct irq_domain_ops. The host_data 1374 * for the IRQ domain must be the &struct gpio_chip. 1375 */ 1376 int gpiochip_irq_domain_activate(struct irq_domain *domain, 1377 struct irq_data *data, bool reserve) 1378 { 1379 struct gpio_chip *gc = domain->host_data; 1380 1381 return gpiochip_lock_as_irq(gc, data->hwirq); 1382 } 1383 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate); 1384 1385 /** 1386 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ 1387 * @domain: The IRQ domain used by this IRQ chip 1388 * @data: Outermost irq_data associated with the IRQ 1389 * 1390 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to 1391 * be used as the deactivate function for the &struct irq_domain_ops. The 1392 * host_data for the IRQ domain must be the &struct gpio_chip. 1393 */ 1394 void gpiochip_irq_domain_deactivate(struct irq_domain *domain, 1395 struct irq_data *data) 1396 { 1397 struct gpio_chip *gc = domain->host_data; 1398 1399 return gpiochip_unlock_as_irq(gc, data->hwirq); 1400 } 1401 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate); 1402 1403 static int gpiochip_to_irq(struct gpio_chip *gc, unsigned int offset) 1404 { 1405 struct irq_domain *domain = gc->irq.domain; 1406 1407 #ifdef CONFIG_GPIOLIB_IRQCHIP 1408 /* 1409 * Avoid race condition with other code, which tries to lookup 1410 * an IRQ before the irqchip has been properly registered, 1411 * i.e. while gpiochip is still being brought up. 1412 */ 1413 if (!gc->irq.initialized) 1414 return -EPROBE_DEFER; 1415 #endif 1416 1417 if (!gpiochip_irqchip_irq_valid(gc, offset)) 1418 return -ENXIO; 1419 1420 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY 1421 if (irq_domain_is_hierarchy(domain)) { 1422 struct irq_fwspec spec; 1423 1424 spec.fwnode = domain->fwnode; 1425 spec.param_count = 2; 1426 spec.param[0] = gc->irq.child_offset_to_irq(gc, offset); 1427 spec.param[1] = IRQ_TYPE_NONE; 1428 1429 return irq_create_fwspec_mapping(&spec); 1430 } 1431 #endif 1432 1433 return irq_create_mapping(domain, offset); 1434 } 1435 1436 int gpiochip_irq_reqres(struct irq_data *d) 1437 { 1438 struct gpio_chip *gc = irq_data_get_irq_chip_data(d); 1439 1440 return gpiochip_reqres_irq(gc, d->hwirq); 1441 } 1442 EXPORT_SYMBOL(gpiochip_irq_reqres); 1443 1444 void gpiochip_irq_relres(struct irq_data *d) 1445 { 1446 struct gpio_chip *gc = irq_data_get_irq_chip_data(d); 1447 1448 gpiochip_relres_irq(gc, d->hwirq); 1449 } 1450 EXPORT_SYMBOL(gpiochip_irq_relres); 1451 1452 static void gpiochip_irq_mask(struct irq_data *d) 1453 { 1454 struct gpio_chip *gc = irq_data_get_irq_chip_data(d); 1455 1456 if (gc->irq.irq_mask) 1457 gc->irq.irq_mask(d); 1458 gpiochip_disable_irq(gc, d->hwirq); 1459 } 1460 1461 static void gpiochip_irq_unmask(struct irq_data *d) 1462 { 1463 struct gpio_chip *gc = irq_data_get_irq_chip_data(d); 1464 1465 gpiochip_enable_irq(gc, d->hwirq); 1466 if (gc->irq.irq_unmask) 1467 gc->irq.irq_unmask(d); 1468 } 1469 1470 static void gpiochip_irq_enable(struct irq_data *d) 1471 { 1472 struct gpio_chip *gc = irq_data_get_irq_chip_data(d); 1473 1474 gpiochip_enable_irq(gc, d->hwirq); 1475 gc->irq.irq_enable(d); 1476 } 1477 1478 static void gpiochip_irq_disable(struct irq_data *d) 1479 { 1480 struct gpio_chip *gc = irq_data_get_irq_chip_data(d); 1481 1482 gc->irq.irq_disable(d); 1483 gpiochip_disable_irq(gc, d->hwirq); 1484 } 1485 1486 static void gpiochip_set_irq_hooks(struct gpio_chip *gc) 1487 { 1488 struct irq_chip *irqchip = gc->irq.chip; 1489 1490 if (irqchip->flags & IRQCHIP_IMMUTABLE) 1491 return; 1492 1493 chip_warn(gc, "not an immutable chip, please consider fixing it!\n"); 1494 1495 if (!irqchip->irq_request_resources && 1496 !irqchip->irq_release_resources) { 1497 irqchip->irq_request_resources = gpiochip_irq_reqres; 1498 irqchip->irq_release_resources = gpiochip_irq_relres; 1499 } 1500 if (WARN_ON(gc->irq.irq_enable)) 1501 return; 1502 /* Check if the irqchip already has this hook... */ 1503 if (irqchip->irq_enable == gpiochip_irq_enable || 1504 irqchip->irq_mask == gpiochip_irq_mask) { 1505 /* 1506 * ...and if so, give a gentle warning that this is bad 1507 * practice. 1508 */ 1509 chip_info(gc, 1510 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n"); 1511 return; 1512 } 1513 1514 if (irqchip->irq_disable) { 1515 gc->irq.irq_disable = irqchip->irq_disable; 1516 irqchip->irq_disable = gpiochip_irq_disable; 1517 } else { 1518 gc->irq.irq_mask = irqchip->irq_mask; 1519 irqchip->irq_mask = gpiochip_irq_mask; 1520 } 1521 1522 if (irqchip->irq_enable) { 1523 gc->irq.irq_enable = irqchip->irq_enable; 1524 irqchip->irq_enable = gpiochip_irq_enable; 1525 } else { 1526 gc->irq.irq_unmask = irqchip->irq_unmask; 1527 irqchip->irq_unmask = gpiochip_irq_unmask; 1528 } 1529 } 1530 1531 /** 1532 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip 1533 * @gc: the GPIO chip to add the IRQ chip to 1534 * @lock_key: lockdep class for IRQ lock 1535 * @request_key: lockdep class for IRQ request 1536 */ 1537 static int gpiochip_add_irqchip(struct gpio_chip *gc, 1538 struct lock_class_key *lock_key, 1539 struct lock_class_key *request_key) 1540 { 1541 struct fwnode_handle *fwnode = dev_fwnode(&gc->gpiodev->dev); 1542 struct irq_chip *irqchip = gc->irq.chip; 1543 unsigned int type; 1544 unsigned int i; 1545 1546 if (!irqchip) 1547 return 0; 1548 1549 if (gc->irq.parent_handler && gc->can_sleep) { 1550 chip_err(gc, "you cannot have chained interrupts on a chip that may sleep\n"); 1551 return -EINVAL; 1552 } 1553 1554 type = gc->irq.default_type; 1555 1556 /* 1557 * Specifying a default trigger is a terrible idea if DT or ACPI is 1558 * used to configure the interrupts, as you may end up with 1559 * conflicting triggers. Tell the user, and reset to NONE. 1560 */ 1561 if (WARN(fwnode && type != IRQ_TYPE_NONE, 1562 "%pfw: Ignoring %u default trigger\n", fwnode, type)) 1563 type = IRQ_TYPE_NONE; 1564 1565 if (gc->to_irq) 1566 chip_warn(gc, "to_irq is redefined in %s and you shouldn't rely on it\n", __func__); 1567 1568 gc->to_irq = gpiochip_to_irq; 1569 gc->irq.default_type = type; 1570 gc->irq.lock_key = lock_key; 1571 gc->irq.request_key = request_key; 1572 1573 /* If a parent irqdomain is provided, let's build a hierarchy */ 1574 if (gpiochip_hierarchy_is_hierarchical(gc)) { 1575 int ret = gpiochip_hierarchy_add_domain(gc); 1576 if (ret) 1577 return ret; 1578 } else { 1579 /* Some drivers provide custom irqdomain ops */ 1580 gc->irq.domain = irq_domain_create_simple(fwnode, 1581 gc->ngpio, 1582 gc->irq.first, 1583 gc->irq.domain_ops ?: &gpiochip_domain_ops, 1584 gc); 1585 if (!gc->irq.domain) 1586 return -EINVAL; 1587 } 1588 1589 if (gc->irq.parent_handler) { 1590 for (i = 0; i < gc->irq.num_parents; i++) { 1591 void *data; 1592 1593 if (gc->irq.per_parent_data) 1594 data = gc->irq.parent_handler_data_array[i]; 1595 else 1596 data = gc->irq.parent_handler_data ?: gc; 1597 1598 /* 1599 * The parent IRQ chip is already using the chip_data 1600 * for this IRQ chip, so our callbacks simply use the 1601 * handler_data. 1602 */ 1603 irq_set_chained_handler_and_data(gc->irq.parents[i], 1604 gc->irq.parent_handler, 1605 data); 1606 } 1607 } 1608 1609 gpiochip_set_irq_hooks(gc); 1610 1611 /* 1612 * Using barrier() here to prevent compiler from reordering 1613 * gc->irq.initialized before initialization of above 1614 * GPIO chip irq members. 1615 */ 1616 barrier(); 1617 1618 gc->irq.initialized = true; 1619 1620 acpi_gpiochip_request_interrupts(gc); 1621 1622 return 0; 1623 } 1624 1625 /** 1626 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip 1627 * @gc: the gpiochip to remove the irqchip from 1628 * 1629 * This is called only from gpiochip_remove() 1630 */ 1631 static void gpiochip_irqchip_remove(struct gpio_chip *gc) 1632 { 1633 struct irq_chip *irqchip = gc->irq.chip; 1634 unsigned int offset; 1635 1636 acpi_gpiochip_free_interrupts(gc); 1637 1638 if (irqchip && gc->irq.parent_handler) { 1639 struct gpio_irq_chip *irq = &gc->irq; 1640 unsigned int i; 1641 1642 for (i = 0; i < irq->num_parents; i++) 1643 irq_set_chained_handler_and_data(irq->parents[i], 1644 NULL, NULL); 1645 } 1646 1647 /* Remove all IRQ mappings and delete the domain */ 1648 if (gc->irq.domain) { 1649 unsigned int irq; 1650 1651 for (offset = 0; offset < gc->ngpio; offset++) { 1652 if (!gpiochip_irqchip_irq_valid(gc, offset)) 1653 continue; 1654 1655 irq = irq_find_mapping(gc->irq.domain, offset); 1656 irq_dispose_mapping(irq); 1657 } 1658 1659 irq_domain_remove(gc->irq.domain); 1660 } 1661 1662 if (irqchip && !(irqchip->flags & IRQCHIP_IMMUTABLE)) { 1663 if (irqchip->irq_request_resources == gpiochip_irq_reqres) { 1664 irqchip->irq_request_resources = NULL; 1665 irqchip->irq_release_resources = NULL; 1666 } 1667 if (irqchip->irq_enable == gpiochip_irq_enable) { 1668 irqchip->irq_enable = gc->irq.irq_enable; 1669 irqchip->irq_disable = gc->irq.irq_disable; 1670 } 1671 } 1672 gc->irq.irq_enable = NULL; 1673 gc->irq.irq_disable = NULL; 1674 gc->irq.chip = NULL; 1675 1676 gpiochip_irqchip_free_valid_mask(gc); 1677 } 1678 1679 /** 1680 * gpiochip_irqchip_add_domain() - adds an irqdomain to a gpiochip 1681 * @gc: the gpiochip to add the irqchip to 1682 * @domain: the irqdomain to add to the gpiochip 1683 * 1684 * This function adds an IRQ domain to the gpiochip. 1685 */ 1686 int gpiochip_irqchip_add_domain(struct gpio_chip *gc, 1687 struct irq_domain *domain) 1688 { 1689 if (!domain) 1690 return -EINVAL; 1691 1692 gc->to_irq = gpiochip_to_irq; 1693 gc->irq.domain = domain; 1694 1695 return 0; 1696 } 1697 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_domain); 1698 1699 #else /* CONFIG_GPIOLIB_IRQCHIP */ 1700 1701 static inline int gpiochip_add_irqchip(struct gpio_chip *gc, 1702 struct lock_class_key *lock_key, 1703 struct lock_class_key *request_key) 1704 { 1705 return 0; 1706 } 1707 static void gpiochip_irqchip_remove(struct gpio_chip *gc) {} 1708 1709 static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gc) 1710 { 1711 return 0; 1712 } 1713 1714 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc) 1715 { 1716 return 0; 1717 } 1718 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc) 1719 { } 1720 1721 #endif /* CONFIG_GPIOLIB_IRQCHIP */ 1722 1723 /** 1724 * gpiochip_generic_request() - request the gpio function for a pin 1725 * @gc: the gpiochip owning the GPIO 1726 * @offset: the offset of the GPIO to request for GPIO function 1727 */ 1728 int gpiochip_generic_request(struct gpio_chip *gc, unsigned int offset) 1729 { 1730 #ifdef CONFIG_PINCTRL 1731 if (list_empty(&gc->gpiodev->pin_ranges)) 1732 return 0; 1733 #endif 1734 1735 return pinctrl_gpio_request(gc->gpiodev->base + offset); 1736 } 1737 EXPORT_SYMBOL_GPL(gpiochip_generic_request); 1738 1739 /** 1740 * gpiochip_generic_free() - free the gpio function from a pin 1741 * @gc: the gpiochip to request the gpio function for 1742 * @offset: the offset of the GPIO to free from GPIO function 1743 */ 1744 void gpiochip_generic_free(struct gpio_chip *gc, unsigned int offset) 1745 { 1746 #ifdef CONFIG_PINCTRL 1747 if (list_empty(&gc->gpiodev->pin_ranges)) 1748 return; 1749 #endif 1750 1751 pinctrl_gpio_free(gc->gpiodev->base + offset); 1752 } 1753 EXPORT_SYMBOL_GPL(gpiochip_generic_free); 1754 1755 /** 1756 * gpiochip_generic_config() - apply configuration for a pin 1757 * @gc: the gpiochip owning the GPIO 1758 * @offset: the offset of the GPIO to apply the configuration 1759 * @config: the configuration to be applied 1760 */ 1761 int gpiochip_generic_config(struct gpio_chip *gc, unsigned int offset, 1762 unsigned long config) 1763 { 1764 return pinctrl_gpio_set_config(gc->gpiodev->base + offset, config); 1765 } 1766 EXPORT_SYMBOL_GPL(gpiochip_generic_config); 1767 1768 #ifdef CONFIG_PINCTRL 1769 1770 /** 1771 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping 1772 * @gc: the gpiochip to add the range for 1773 * @pctldev: the pin controller to map to 1774 * @gpio_offset: the start offset in the current gpio_chip number space 1775 * @pin_group: name of the pin group inside the pin controller 1776 * 1777 * Calling this function directly from a DeviceTree-supported 1778 * pinctrl driver is DEPRECATED. Please see Section 2.1 of 1779 * Documentation/devicetree/bindings/gpio/gpio.txt on how to 1780 * bind pinctrl and gpio drivers via the "gpio-ranges" property. 1781 */ 1782 int gpiochip_add_pingroup_range(struct gpio_chip *gc, 1783 struct pinctrl_dev *pctldev, 1784 unsigned int gpio_offset, const char *pin_group) 1785 { 1786 struct gpio_pin_range *pin_range; 1787 struct gpio_device *gdev = gc->gpiodev; 1788 int ret; 1789 1790 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); 1791 if (!pin_range) { 1792 chip_err(gc, "failed to allocate pin ranges\n"); 1793 return -ENOMEM; 1794 } 1795 1796 /* Use local offset as range ID */ 1797 pin_range->range.id = gpio_offset; 1798 pin_range->range.gc = gc; 1799 pin_range->range.name = gc->label; 1800 pin_range->range.base = gdev->base + gpio_offset; 1801 pin_range->pctldev = pctldev; 1802 1803 ret = pinctrl_get_group_pins(pctldev, pin_group, 1804 &pin_range->range.pins, 1805 &pin_range->range.npins); 1806 if (ret < 0) { 1807 kfree(pin_range); 1808 return ret; 1809 } 1810 1811 pinctrl_add_gpio_range(pctldev, &pin_range->range); 1812 1813 chip_dbg(gc, "created GPIO range %d->%d ==> %s PINGRP %s\n", 1814 gpio_offset, gpio_offset + pin_range->range.npins - 1, 1815 pinctrl_dev_get_devname(pctldev), pin_group); 1816 1817 list_add_tail(&pin_range->node, &gdev->pin_ranges); 1818 1819 return 0; 1820 } 1821 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); 1822 1823 /** 1824 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping 1825 * @gc: the gpiochip to add the range for 1826 * @pinctl_name: the dev_name() of the pin controller to map to 1827 * @gpio_offset: the start offset in the current gpio_chip number space 1828 * @pin_offset: the start offset in the pin controller number space 1829 * @npins: the number of pins from the offset of each pin space (GPIO and 1830 * pin controller) to accumulate in this range 1831 * 1832 * Returns: 1833 * 0 on success, or a negative error-code on failure. 1834 * 1835 * Calling this function directly from a DeviceTree-supported 1836 * pinctrl driver is DEPRECATED. Please see Section 2.1 of 1837 * Documentation/devicetree/bindings/gpio/gpio.txt on how to 1838 * bind pinctrl and gpio drivers via the "gpio-ranges" property. 1839 */ 1840 int gpiochip_add_pin_range(struct gpio_chip *gc, const char *pinctl_name, 1841 unsigned int gpio_offset, unsigned int pin_offset, 1842 unsigned int npins) 1843 { 1844 struct gpio_pin_range *pin_range; 1845 struct gpio_device *gdev = gc->gpiodev; 1846 int ret; 1847 1848 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); 1849 if (!pin_range) { 1850 chip_err(gc, "failed to allocate pin ranges\n"); 1851 return -ENOMEM; 1852 } 1853 1854 /* Use local offset as range ID */ 1855 pin_range->range.id = gpio_offset; 1856 pin_range->range.gc = gc; 1857 pin_range->range.name = gc->label; 1858 pin_range->range.base = gdev->base + gpio_offset; 1859 pin_range->range.pin_base = pin_offset; 1860 pin_range->range.npins = npins; 1861 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name, 1862 &pin_range->range); 1863 if (IS_ERR(pin_range->pctldev)) { 1864 ret = PTR_ERR(pin_range->pctldev); 1865 chip_err(gc, "could not create pin range\n"); 1866 kfree(pin_range); 1867 return ret; 1868 } 1869 chip_dbg(gc, "created GPIO range %d->%d ==> %s PIN %d->%d\n", 1870 gpio_offset, gpio_offset + npins - 1, 1871 pinctl_name, 1872 pin_offset, pin_offset + npins - 1); 1873 1874 list_add_tail(&pin_range->node, &gdev->pin_ranges); 1875 1876 return 0; 1877 } 1878 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range); 1879 1880 /** 1881 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings 1882 * @gc: the chip to remove all the mappings for 1883 */ 1884 void gpiochip_remove_pin_ranges(struct gpio_chip *gc) 1885 { 1886 struct gpio_pin_range *pin_range, *tmp; 1887 struct gpio_device *gdev = gc->gpiodev; 1888 1889 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) { 1890 list_del(&pin_range->node); 1891 pinctrl_remove_gpio_range(pin_range->pctldev, 1892 &pin_range->range); 1893 kfree(pin_range); 1894 } 1895 } 1896 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); 1897 1898 #endif /* CONFIG_PINCTRL */ 1899 1900 /* These "optional" allocation calls help prevent drivers from stomping 1901 * on each other, and help provide better diagnostics in debugfs. 1902 * They're called even less than the "set direction" calls. 1903 */ 1904 static int gpiod_request_commit(struct gpio_desc *desc, const char *label) 1905 { 1906 struct gpio_chip *gc = desc->gdev->chip; 1907 int ret; 1908 unsigned long flags; 1909 unsigned offset; 1910 1911 if (label) { 1912 label = kstrdup_const(label, GFP_KERNEL); 1913 if (!label) 1914 return -ENOMEM; 1915 } 1916 1917 spin_lock_irqsave(&gpio_lock, flags); 1918 1919 /* NOTE: gpio_request() can be called in early boot, 1920 * before IRQs are enabled, for non-sleeping (SOC) GPIOs. 1921 */ 1922 1923 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) { 1924 desc_set_label(desc, label ? : "?"); 1925 } else { 1926 ret = -EBUSY; 1927 goto out_free_unlock; 1928 } 1929 1930 if (gc->request) { 1931 /* gc->request may sleep */ 1932 spin_unlock_irqrestore(&gpio_lock, flags); 1933 offset = gpio_chip_hwgpio(desc); 1934 if (gpiochip_line_is_valid(gc, offset)) 1935 ret = gc->request(gc, offset); 1936 else 1937 ret = -EINVAL; 1938 spin_lock_irqsave(&gpio_lock, flags); 1939 1940 if (ret) { 1941 desc_set_label(desc, NULL); 1942 clear_bit(FLAG_REQUESTED, &desc->flags); 1943 goto out_free_unlock; 1944 } 1945 } 1946 if (gc->get_direction) { 1947 /* gc->get_direction may sleep */ 1948 spin_unlock_irqrestore(&gpio_lock, flags); 1949 gpiod_get_direction(desc); 1950 spin_lock_irqsave(&gpio_lock, flags); 1951 } 1952 spin_unlock_irqrestore(&gpio_lock, flags); 1953 return 0; 1954 1955 out_free_unlock: 1956 spin_unlock_irqrestore(&gpio_lock, flags); 1957 kfree_const(label); 1958 return ret; 1959 } 1960 1961 /* 1962 * This descriptor validation needs to be inserted verbatim into each 1963 * function taking a descriptor, so we need to use a preprocessor 1964 * macro to avoid endless duplication. If the desc is NULL it is an 1965 * optional GPIO and calls should just bail out. 1966 */ 1967 static int validate_desc(const struct gpio_desc *desc, const char *func) 1968 { 1969 if (!desc) 1970 return 0; 1971 if (IS_ERR(desc)) { 1972 pr_warn("%s: invalid GPIO (errorpointer)\n", func); 1973 return PTR_ERR(desc); 1974 } 1975 if (!desc->gdev) { 1976 pr_warn("%s: invalid GPIO (no device)\n", func); 1977 return -EINVAL; 1978 } 1979 if (!desc->gdev->chip) { 1980 dev_warn(&desc->gdev->dev, 1981 "%s: backing chip is gone\n", func); 1982 return 0; 1983 } 1984 return 1; 1985 } 1986 1987 #define VALIDATE_DESC(desc) do { \ 1988 int __valid = validate_desc(desc, __func__); \ 1989 if (__valid <= 0) \ 1990 return __valid; \ 1991 } while (0) 1992 1993 #define VALIDATE_DESC_VOID(desc) do { \ 1994 int __valid = validate_desc(desc, __func__); \ 1995 if (__valid <= 0) \ 1996 return; \ 1997 } while (0) 1998 1999 int gpiod_request(struct gpio_desc *desc, const char *label) 2000 { 2001 int ret = -EPROBE_DEFER; 2002 struct gpio_device *gdev; 2003 2004 VALIDATE_DESC(desc); 2005 gdev = desc->gdev; 2006 2007 if (try_module_get(gdev->owner)) { 2008 ret = gpiod_request_commit(desc, label); 2009 if (ret) 2010 module_put(gdev->owner); 2011 else 2012 get_device(&gdev->dev); 2013 } 2014 2015 if (ret) 2016 gpiod_dbg(desc, "%s: status %d\n", __func__, ret); 2017 2018 return ret; 2019 } 2020 2021 static bool gpiod_free_commit(struct gpio_desc *desc) 2022 { 2023 bool ret = false; 2024 unsigned long flags; 2025 struct gpio_chip *gc; 2026 2027 might_sleep(); 2028 2029 gpiod_unexport(desc); 2030 2031 spin_lock_irqsave(&gpio_lock, flags); 2032 2033 gc = desc->gdev->chip; 2034 if (gc && test_bit(FLAG_REQUESTED, &desc->flags)) { 2035 if (gc->free) { 2036 spin_unlock_irqrestore(&gpio_lock, flags); 2037 might_sleep_if(gc->can_sleep); 2038 gc->free(gc, gpio_chip_hwgpio(desc)); 2039 spin_lock_irqsave(&gpio_lock, flags); 2040 } 2041 kfree_const(desc->label); 2042 desc_set_label(desc, NULL); 2043 clear_bit(FLAG_ACTIVE_LOW, &desc->flags); 2044 clear_bit(FLAG_REQUESTED, &desc->flags); 2045 clear_bit(FLAG_OPEN_DRAIN, &desc->flags); 2046 clear_bit(FLAG_OPEN_SOURCE, &desc->flags); 2047 clear_bit(FLAG_PULL_UP, &desc->flags); 2048 clear_bit(FLAG_PULL_DOWN, &desc->flags); 2049 clear_bit(FLAG_BIAS_DISABLE, &desc->flags); 2050 clear_bit(FLAG_EDGE_RISING, &desc->flags); 2051 clear_bit(FLAG_EDGE_FALLING, &desc->flags); 2052 clear_bit(FLAG_IS_HOGGED, &desc->flags); 2053 #ifdef CONFIG_OF_DYNAMIC 2054 desc->hog = NULL; 2055 #endif 2056 #ifdef CONFIG_GPIO_CDEV 2057 WRITE_ONCE(desc->debounce_period_us, 0); 2058 #endif 2059 ret = true; 2060 } 2061 2062 spin_unlock_irqrestore(&gpio_lock, flags); 2063 blocking_notifier_call_chain(&desc->gdev->notifier, 2064 GPIOLINE_CHANGED_RELEASED, desc); 2065 2066 return ret; 2067 } 2068 2069 void gpiod_free(struct gpio_desc *desc) 2070 { 2071 if (desc && desc->gdev && gpiod_free_commit(desc)) { 2072 module_put(desc->gdev->owner); 2073 put_device(&desc->gdev->dev); 2074 } else { 2075 WARN_ON(extra_checks); 2076 } 2077 } 2078 2079 /** 2080 * gpiochip_is_requested - return string iff signal was requested 2081 * @gc: controller managing the signal 2082 * @offset: of signal within controller's 0..(ngpio - 1) range 2083 * 2084 * Returns NULL if the GPIO is not currently requested, else a string. 2085 * The string returned is the label passed to gpio_request(); if none has been 2086 * passed it is a meaningless, non-NULL constant. 2087 * 2088 * This function is for use by GPIO controller drivers. The label can 2089 * help with diagnostics, and knowing that the signal is used as a GPIO 2090 * can help avoid accidentally multiplexing it to another controller. 2091 */ 2092 const char *gpiochip_is_requested(struct gpio_chip *gc, unsigned int offset) 2093 { 2094 struct gpio_desc *desc; 2095 2096 desc = gpiochip_get_desc(gc, offset); 2097 if (IS_ERR(desc)) 2098 return NULL; 2099 2100 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0) 2101 return NULL; 2102 return desc->label; 2103 } 2104 EXPORT_SYMBOL_GPL(gpiochip_is_requested); 2105 2106 /** 2107 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor 2108 * @gc: GPIO chip 2109 * @hwnum: hardware number of the GPIO for which to request the descriptor 2110 * @label: label for the GPIO 2111 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to 2112 * specify things like line inversion semantics with the machine flags 2113 * such as GPIO_OUT_LOW 2114 * @dflags: descriptor request flags for this GPIO or 0 if default, this 2115 * can be used to specify consumer semantics such as open drain 2116 * 2117 * Function allows GPIO chip drivers to request and use their own GPIO 2118 * descriptors via gpiolib API. Difference to gpiod_request() is that this 2119 * function will not increase reference count of the GPIO chip module. This 2120 * allows the GPIO chip module to be unloaded as needed (we assume that the 2121 * GPIO chip driver handles freeing the GPIOs it has requested). 2122 * 2123 * Returns: 2124 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error 2125 * code on failure. 2126 */ 2127 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc, 2128 unsigned int hwnum, 2129 const char *label, 2130 enum gpio_lookup_flags lflags, 2131 enum gpiod_flags dflags) 2132 { 2133 struct gpio_desc *desc = gpiochip_get_desc(gc, hwnum); 2134 int ret; 2135 2136 if (IS_ERR(desc)) { 2137 chip_err(gc, "failed to get GPIO descriptor\n"); 2138 return desc; 2139 } 2140 2141 ret = gpiod_request_commit(desc, label); 2142 if (ret < 0) 2143 return ERR_PTR(ret); 2144 2145 ret = gpiod_configure_flags(desc, label, lflags, dflags); 2146 if (ret) { 2147 chip_err(gc, "setup of own GPIO %s failed\n", label); 2148 gpiod_free_commit(desc); 2149 return ERR_PTR(ret); 2150 } 2151 2152 return desc; 2153 } 2154 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc); 2155 2156 /** 2157 * gpiochip_free_own_desc - Free GPIO requested by the chip driver 2158 * @desc: GPIO descriptor to free 2159 * 2160 * Function frees the given GPIO requested previously with 2161 * gpiochip_request_own_desc(). 2162 */ 2163 void gpiochip_free_own_desc(struct gpio_desc *desc) 2164 { 2165 if (desc) 2166 gpiod_free_commit(desc); 2167 } 2168 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc); 2169 2170 /* 2171 * Drivers MUST set GPIO direction before making get/set calls. In 2172 * some cases this is done in early boot, before IRQs are enabled. 2173 * 2174 * As a rule these aren't called more than once (except for drivers 2175 * using the open-drain emulation idiom) so these are natural places 2176 * to accumulate extra debugging checks. Note that we can't (yet) 2177 * rely on gpio_request() having been called beforehand. 2178 */ 2179 2180 static int gpio_do_set_config(struct gpio_chip *gc, unsigned int offset, 2181 unsigned long config) 2182 { 2183 if (!gc->set_config) 2184 return -ENOTSUPP; 2185 2186 return gc->set_config(gc, offset, config); 2187 } 2188 2189 static int gpio_set_config_with_argument(struct gpio_desc *desc, 2190 enum pin_config_param mode, 2191 u32 argument) 2192 { 2193 struct gpio_chip *gc = desc->gdev->chip; 2194 unsigned long config; 2195 2196 config = pinconf_to_config_packed(mode, argument); 2197 return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config); 2198 } 2199 2200 static int gpio_set_config_with_argument_optional(struct gpio_desc *desc, 2201 enum pin_config_param mode, 2202 u32 argument) 2203 { 2204 struct device *dev = &desc->gdev->dev; 2205 int gpio = gpio_chip_hwgpio(desc); 2206 int ret; 2207 2208 ret = gpio_set_config_with_argument(desc, mode, argument); 2209 if (ret != -ENOTSUPP) 2210 return ret; 2211 2212 switch (mode) { 2213 case PIN_CONFIG_PERSIST_STATE: 2214 dev_dbg(dev, "Persistence not supported for GPIO %d\n", gpio); 2215 break; 2216 default: 2217 break; 2218 } 2219 2220 return 0; 2221 } 2222 2223 static int gpio_set_config(struct gpio_desc *desc, enum pin_config_param mode) 2224 { 2225 return gpio_set_config_with_argument(desc, mode, 0); 2226 } 2227 2228 static int gpio_set_bias(struct gpio_desc *desc) 2229 { 2230 enum pin_config_param bias; 2231 unsigned int arg; 2232 2233 if (test_bit(FLAG_BIAS_DISABLE, &desc->flags)) 2234 bias = PIN_CONFIG_BIAS_DISABLE; 2235 else if (test_bit(FLAG_PULL_UP, &desc->flags)) 2236 bias = PIN_CONFIG_BIAS_PULL_UP; 2237 else if (test_bit(FLAG_PULL_DOWN, &desc->flags)) 2238 bias = PIN_CONFIG_BIAS_PULL_DOWN; 2239 else 2240 return 0; 2241 2242 switch (bias) { 2243 case PIN_CONFIG_BIAS_PULL_DOWN: 2244 case PIN_CONFIG_BIAS_PULL_UP: 2245 arg = 1; 2246 break; 2247 2248 default: 2249 arg = 0; 2250 break; 2251 } 2252 2253 return gpio_set_config_with_argument_optional(desc, bias, arg); 2254 } 2255 2256 /** 2257 * gpio_set_debounce_timeout() - Set debounce timeout 2258 * @desc: GPIO descriptor to set the debounce timeout 2259 * @debounce: Debounce timeout in microseconds 2260 * 2261 * The function calls the certain GPIO driver to set debounce timeout 2262 * in the hardware. 2263 * 2264 * Returns 0 on success, or negative error code otherwise. 2265 */ 2266 int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce) 2267 { 2268 return gpio_set_config_with_argument_optional(desc, 2269 PIN_CONFIG_INPUT_DEBOUNCE, 2270 debounce); 2271 } 2272 2273 /** 2274 * gpiod_direction_input - set the GPIO direction to input 2275 * @desc: GPIO to set to input 2276 * 2277 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can 2278 * be called safely on it. 2279 * 2280 * Return 0 in case of success, else an error code. 2281 */ 2282 int gpiod_direction_input(struct gpio_desc *desc) 2283 { 2284 struct gpio_chip *gc; 2285 int ret = 0; 2286 2287 VALIDATE_DESC(desc); 2288 gc = desc->gdev->chip; 2289 2290 /* 2291 * It is legal to have no .get() and .direction_input() specified if 2292 * the chip is output-only, but you can't specify .direction_input() 2293 * and not support the .get() operation, that doesn't make sense. 2294 */ 2295 if (!gc->get && gc->direction_input) { 2296 gpiod_warn(desc, 2297 "%s: missing get() but have direction_input()\n", 2298 __func__); 2299 return -EIO; 2300 } 2301 2302 /* 2303 * If we have a .direction_input() callback, things are simple, 2304 * just call it. Else we are some input-only chip so try to check the 2305 * direction (if .get_direction() is supported) else we silently 2306 * assume we are in input mode after this. 2307 */ 2308 if (gc->direction_input) { 2309 ret = gc->direction_input(gc, gpio_chip_hwgpio(desc)); 2310 } else if (gc->get_direction && 2311 (gc->get_direction(gc, gpio_chip_hwgpio(desc)) != 1)) { 2312 gpiod_warn(desc, 2313 "%s: missing direction_input() operation and line is output\n", 2314 __func__); 2315 return -EIO; 2316 } 2317 if (ret == 0) { 2318 clear_bit(FLAG_IS_OUT, &desc->flags); 2319 ret = gpio_set_bias(desc); 2320 } 2321 2322 trace_gpio_direction(desc_to_gpio(desc), 1, ret); 2323 2324 return ret; 2325 } 2326 EXPORT_SYMBOL_GPL(gpiod_direction_input); 2327 2328 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value) 2329 { 2330 struct gpio_chip *gc = desc->gdev->chip; 2331 int val = !!value; 2332 int ret = 0; 2333 2334 /* 2335 * It's OK not to specify .direction_output() if the gpiochip is 2336 * output-only, but if there is then not even a .set() operation it 2337 * is pretty tricky to drive the output line. 2338 */ 2339 if (!gc->set && !gc->direction_output) { 2340 gpiod_warn(desc, 2341 "%s: missing set() and direction_output() operations\n", 2342 __func__); 2343 return -EIO; 2344 } 2345 2346 if (gc->direction_output) { 2347 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val); 2348 } else { 2349 /* Check that we are in output mode if we can */ 2350 if (gc->get_direction && 2351 gc->get_direction(gc, gpio_chip_hwgpio(desc))) { 2352 gpiod_warn(desc, 2353 "%s: missing direction_output() operation\n", 2354 __func__); 2355 return -EIO; 2356 } 2357 /* 2358 * If we can't actively set the direction, we are some 2359 * output-only chip, so just drive the output as desired. 2360 */ 2361 gc->set(gc, gpio_chip_hwgpio(desc), val); 2362 } 2363 2364 if (!ret) 2365 set_bit(FLAG_IS_OUT, &desc->flags); 2366 trace_gpio_value(desc_to_gpio(desc), 0, val); 2367 trace_gpio_direction(desc_to_gpio(desc), 0, ret); 2368 return ret; 2369 } 2370 2371 /** 2372 * gpiod_direction_output_raw - set the GPIO direction to output 2373 * @desc: GPIO to set to output 2374 * @value: initial output value of the GPIO 2375 * 2376 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can 2377 * be called safely on it. The initial value of the output must be specified 2378 * as raw value on the physical line without regard for the ACTIVE_LOW status. 2379 * 2380 * Return 0 in case of success, else an error code. 2381 */ 2382 int gpiod_direction_output_raw(struct gpio_desc *desc, int value) 2383 { 2384 VALIDATE_DESC(desc); 2385 return gpiod_direction_output_raw_commit(desc, value); 2386 } 2387 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); 2388 2389 /** 2390 * gpiod_direction_output - set the GPIO direction to output 2391 * @desc: GPIO to set to output 2392 * @value: initial output value of the GPIO 2393 * 2394 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can 2395 * be called safely on it. The initial value of the output must be specified 2396 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into 2397 * account. 2398 * 2399 * Return 0 in case of success, else an error code. 2400 */ 2401 int gpiod_direction_output(struct gpio_desc *desc, int value) 2402 { 2403 int ret; 2404 2405 VALIDATE_DESC(desc); 2406 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) 2407 value = !value; 2408 else 2409 value = !!value; 2410 2411 /* GPIOs used for enabled IRQs shall not be set as output */ 2412 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) && 2413 test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) { 2414 gpiod_err(desc, 2415 "%s: tried to set a GPIO tied to an IRQ as output\n", 2416 __func__); 2417 return -EIO; 2418 } 2419 2420 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) { 2421 /* First see if we can enable open drain in hardware */ 2422 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_DRAIN); 2423 if (!ret) 2424 goto set_output_value; 2425 /* Emulate open drain by not actively driving the line high */ 2426 if (value) { 2427 ret = gpiod_direction_input(desc); 2428 goto set_output_flag; 2429 } 2430 } 2431 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) { 2432 ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_SOURCE); 2433 if (!ret) 2434 goto set_output_value; 2435 /* Emulate open source by not actively driving the line low */ 2436 if (!value) { 2437 ret = gpiod_direction_input(desc); 2438 goto set_output_flag; 2439 } 2440 } else { 2441 gpio_set_config(desc, PIN_CONFIG_DRIVE_PUSH_PULL); 2442 } 2443 2444 set_output_value: 2445 ret = gpio_set_bias(desc); 2446 if (ret) 2447 return ret; 2448 return gpiod_direction_output_raw_commit(desc, value); 2449 2450 set_output_flag: 2451 /* 2452 * When emulating open-source or open-drain functionalities by not 2453 * actively driving the line (setting mode to input) we still need to 2454 * set the IS_OUT flag or otherwise we won't be able to set the line 2455 * value anymore. 2456 */ 2457 if (ret == 0) 2458 set_bit(FLAG_IS_OUT, &desc->flags); 2459 return ret; 2460 } 2461 EXPORT_SYMBOL_GPL(gpiod_direction_output); 2462 2463 /** 2464 * gpiod_set_config - sets @config for a GPIO 2465 * @desc: descriptor of the GPIO for which to set the configuration 2466 * @config: Same packed config format as generic pinconf 2467 * 2468 * Returns: 2469 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the 2470 * configuration. 2471 */ 2472 int gpiod_set_config(struct gpio_desc *desc, unsigned long config) 2473 { 2474 struct gpio_chip *gc; 2475 2476 VALIDATE_DESC(desc); 2477 gc = desc->gdev->chip; 2478 2479 return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config); 2480 } 2481 EXPORT_SYMBOL_GPL(gpiod_set_config); 2482 2483 /** 2484 * gpiod_set_debounce - sets @debounce time for a GPIO 2485 * @desc: descriptor of the GPIO for which to set debounce time 2486 * @debounce: debounce time in microseconds 2487 * 2488 * Returns: 2489 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the 2490 * debounce time. 2491 */ 2492 int gpiod_set_debounce(struct gpio_desc *desc, unsigned int debounce) 2493 { 2494 unsigned long config; 2495 2496 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce); 2497 return gpiod_set_config(desc, config); 2498 } 2499 EXPORT_SYMBOL_GPL(gpiod_set_debounce); 2500 2501 /** 2502 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset 2503 * @desc: descriptor of the GPIO for which to configure persistence 2504 * @transitory: True to lose state on suspend or reset, false for persistence 2505 * 2506 * Returns: 2507 * 0 on success, otherwise a negative error code. 2508 */ 2509 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory) 2510 { 2511 VALIDATE_DESC(desc); 2512 /* 2513 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for 2514 * persistence state. 2515 */ 2516 assign_bit(FLAG_TRANSITORY, &desc->flags, transitory); 2517 2518 /* If the driver supports it, set the persistence state now */ 2519 return gpio_set_config_with_argument_optional(desc, 2520 PIN_CONFIG_PERSIST_STATE, 2521 !transitory); 2522 } 2523 EXPORT_SYMBOL_GPL(gpiod_set_transitory); 2524 2525 /** 2526 * gpiod_is_active_low - test whether a GPIO is active-low or not 2527 * @desc: the gpio descriptor to test 2528 * 2529 * Returns 1 if the GPIO is active-low, 0 otherwise. 2530 */ 2531 int gpiod_is_active_low(const struct gpio_desc *desc) 2532 { 2533 VALIDATE_DESC(desc); 2534 return test_bit(FLAG_ACTIVE_LOW, &desc->flags); 2535 } 2536 EXPORT_SYMBOL_GPL(gpiod_is_active_low); 2537 2538 /** 2539 * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not 2540 * @desc: the gpio descriptor to change 2541 */ 2542 void gpiod_toggle_active_low(struct gpio_desc *desc) 2543 { 2544 VALIDATE_DESC_VOID(desc); 2545 change_bit(FLAG_ACTIVE_LOW, &desc->flags); 2546 } 2547 EXPORT_SYMBOL_GPL(gpiod_toggle_active_low); 2548 2549 /* I/O calls are only valid after configuration completed; the relevant 2550 * "is this a valid GPIO" error checks should already have been done. 2551 * 2552 * "Get" operations are often inlinable as reading a pin value register, 2553 * and masking the relevant bit in that register. 2554 * 2555 * When "set" operations are inlinable, they involve writing that mask to 2556 * one register to set a low value, or a different register to set it high. 2557 * Otherwise locking is needed, so there may be little value to inlining. 2558 * 2559 *------------------------------------------------------------------------ 2560 * 2561 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers 2562 * have requested the GPIO. That can include implicit requesting by 2563 * a direction setting call. Marking a gpio as requested locks its chip 2564 * in memory, guaranteeing that these table lookups need no more locking 2565 * and that gpiochip_remove() will fail. 2566 * 2567 * REVISIT when debugging, consider adding some instrumentation to ensure 2568 * that the GPIO was actually requested. 2569 */ 2570 2571 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc) 2572 { 2573 struct gpio_chip *gc; 2574 int offset; 2575 int value; 2576 2577 gc = desc->gdev->chip; 2578 offset = gpio_chip_hwgpio(desc); 2579 value = gc->get ? gc->get(gc, offset) : -EIO; 2580 value = value < 0 ? value : !!value; 2581 trace_gpio_value(desc_to_gpio(desc), 1, value); 2582 return value; 2583 } 2584 2585 static int gpio_chip_get_multiple(struct gpio_chip *gc, 2586 unsigned long *mask, unsigned long *bits) 2587 { 2588 if (gc->get_multiple) { 2589 return gc->get_multiple(gc, mask, bits); 2590 } else if (gc->get) { 2591 int i, value; 2592 2593 for_each_set_bit(i, mask, gc->ngpio) { 2594 value = gc->get(gc, i); 2595 if (value < 0) 2596 return value; 2597 __assign_bit(i, bits, value); 2598 } 2599 return 0; 2600 } 2601 return -EIO; 2602 } 2603 2604 int gpiod_get_array_value_complex(bool raw, bool can_sleep, 2605 unsigned int array_size, 2606 struct gpio_desc **desc_array, 2607 struct gpio_array *array_info, 2608 unsigned long *value_bitmap) 2609 { 2610 int ret, i = 0; 2611 2612 /* 2613 * Validate array_info against desc_array and its size. 2614 * It should immediately follow desc_array if both 2615 * have been obtained from the same gpiod_get_array() call. 2616 */ 2617 if (array_info && array_info->desc == desc_array && 2618 array_size <= array_info->size && 2619 (void *)array_info == desc_array + array_info->size) { 2620 if (!can_sleep) 2621 WARN_ON(array_info->chip->can_sleep); 2622 2623 ret = gpio_chip_get_multiple(array_info->chip, 2624 array_info->get_mask, 2625 value_bitmap); 2626 if (ret) 2627 return ret; 2628 2629 if (!raw && !bitmap_empty(array_info->invert_mask, array_size)) 2630 bitmap_xor(value_bitmap, value_bitmap, 2631 array_info->invert_mask, array_size); 2632 2633 i = find_first_zero_bit(array_info->get_mask, array_size); 2634 if (i == array_size) 2635 return 0; 2636 } else { 2637 array_info = NULL; 2638 } 2639 2640 while (i < array_size) { 2641 struct gpio_chip *gc = desc_array[i]->gdev->chip; 2642 DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO); 2643 DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO); 2644 unsigned long *mask, *bits; 2645 int first, j; 2646 2647 if (likely(gc->ngpio <= FASTPATH_NGPIO)) { 2648 mask = fastpath_mask; 2649 bits = fastpath_bits; 2650 } else { 2651 gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC; 2652 2653 mask = bitmap_alloc(gc->ngpio, flags); 2654 if (!mask) 2655 return -ENOMEM; 2656 2657 bits = bitmap_alloc(gc->ngpio, flags); 2658 if (!bits) { 2659 bitmap_free(mask); 2660 return -ENOMEM; 2661 } 2662 } 2663 2664 bitmap_zero(mask, gc->ngpio); 2665 2666 if (!can_sleep) 2667 WARN_ON(gc->can_sleep); 2668 2669 /* collect all inputs belonging to the same chip */ 2670 first = i; 2671 do { 2672 const struct gpio_desc *desc = desc_array[i]; 2673 int hwgpio = gpio_chip_hwgpio(desc); 2674 2675 __set_bit(hwgpio, mask); 2676 i++; 2677 2678 if (array_info) 2679 i = find_next_zero_bit(array_info->get_mask, 2680 array_size, i); 2681 } while ((i < array_size) && 2682 (desc_array[i]->gdev->chip == gc)); 2683 2684 ret = gpio_chip_get_multiple(gc, mask, bits); 2685 if (ret) { 2686 if (mask != fastpath_mask) 2687 bitmap_free(mask); 2688 if (bits != fastpath_bits) 2689 bitmap_free(bits); 2690 return ret; 2691 } 2692 2693 for (j = first; j < i; ) { 2694 const struct gpio_desc *desc = desc_array[j]; 2695 int hwgpio = gpio_chip_hwgpio(desc); 2696 int value = test_bit(hwgpio, bits); 2697 2698 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags)) 2699 value = !value; 2700 __assign_bit(j, value_bitmap, value); 2701 trace_gpio_value(desc_to_gpio(desc), 1, value); 2702 j++; 2703 2704 if (array_info) 2705 j = find_next_zero_bit(array_info->get_mask, i, 2706 j); 2707 } 2708 2709 if (mask != fastpath_mask) 2710 bitmap_free(mask); 2711 if (bits != fastpath_bits) 2712 bitmap_free(bits); 2713 } 2714 return 0; 2715 } 2716 2717 /** 2718 * gpiod_get_raw_value() - return a gpio's raw value 2719 * @desc: gpio whose value will be returned 2720 * 2721 * Return the GPIO's raw value, i.e. the value of the physical line disregarding 2722 * its ACTIVE_LOW status, or negative errno on failure. 2723 * 2724 * This function can be called from contexts where we cannot sleep, and will 2725 * complain if the GPIO chip functions potentially sleep. 2726 */ 2727 int gpiod_get_raw_value(const struct gpio_desc *desc) 2728 { 2729 VALIDATE_DESC(desc); 2730 /* Should be using gpiod_get_raw_value_cansleep() */ 2731 WARN_ON(desc->gdev->chip->can_sleep); 2732 return gpiod_get_raw_value_commit(desc); 2733 } 2734 EXPORT_SYMBOL_GPL(gpiod_get_raw_value); 2735 2736 /** 2737 * gpiod_get_value() - return a gpio's value 2738 * @desc: gpio whose value will be returned 2739 * 2740 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into 2741 * account, or negative errno on failure. 2742 * 2743 * This function can be called from contexts where we cannot sleep, and will 2744 * complain if the GPIO chip functions potentially sleep. 2745 */ 2746 int gpiod_get_value(const struct gpio_desc *desc) 2747 { 2748 int value; 2749 2750 VALIDATE_DESC(desc); 2751 /* Should be using gpiod_get_value_cansleep() */ 2752 WARN_ON(desc->gdev->chip->can_sleep); 2753 2754 value = gpiod_get_raw_value_commit(desc); 2755 if (value < 0) 2756 return value; 2757 2758 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) 2759 value = !value; 2760 2761 return value; 2762 } 2763 EXPORT_SYMBOL_GPL(gpiod_get_value); 2764 2765 /** 2766 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs 2767 * @array_size: number of elements in the descriptor array / value bitmap 2768 * @desc_array: array of GPIO descriptors whose values will be read 2769 * @array_info: information on applicability of fast bitmap processing path 2770 * @value_bitmap: bitmap to store the read values 2771 * 2772 * Read the raw values of the GPIOs, i.e. the values of the physical lines 2773 * without regard for their ACTIVE_LOW status. Return 0 in case of success, 2774 * else an error code. 2775 * 2776 * This function can be called from contexts where we cannot sleep, 2777 * and it will complain if the GPIO chip functions potentially sleep. 2778 */ 2779 int gpiod_get_raw_array_value(unsigned int array_size, 2780 struct gpio_desc **desc_array, 2781 struct gpio_array *array_info, 2782 unsigned long *value_bitmap) 2783 { 2784 if (!desc_array) 2785 return -EINVAL; 2786 return gpiod_get_array_value_complex(true, false, array_size, 2787 desc_array, array_info, 2788 value_bitmap); 2789 } 2790 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value); 2791 2792 /** 2793 * gpiod_get_array_value() - read values from an array of GPIOs 2794 * @array_size: number of elements in the descriptor array / value bitmap 2795 * @desc_array: array of GPIO descriptors whose values will be read 2796 * @array_info: information on applicability of fast bitmap processing path 2797 * @value_bitmap: bitmap to store the read values 2798 * 2799 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status 2800 * into account. Return 0 in case of success, else an error code. 2801 * 2802 * This function can be called from contexts where we cannot sleep, 2803 * and it will complain if the GPIO chip functions potentially sleep. 2804 */ 2805 int gpiod_get_array_value(unsigned int array_size, 2806 struct gpio_desc **desc_array, 2807 struct gpio_array *array_info, 2808 unsigned long *value_bitmap) 2809 { 2810 if (!desc_array) 2811 return -EINVAL; 2812 return gpiod_get_array_value_complex(false, false, array_size, 2813 desc_array, array_info, 2814 value_bitmap); 2815 } 2816 EXPORT_SYMBOL_GPL(gpiod_get_array_value); 2817 2818 /* 2819 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value. 2820 * @desc: gpio descriptor whose state need to be set. 2821 * @value: Non-zero for setting it HIGH otherwise it will set to LOW. 2822 */ 2823 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value) 2824 { 2825 int ret = 0; 2826 struct gpio_chip *gc = desc->gdev->chip; 2827 int offset = gpio_chip_hwgpio(desc); 2828 2829 if (value) { 2830 ret = gc->direction_input(gc, offset); 2831 } else { 2832 ret = gc->direction_output(gc, offset, 0); 2833 if (!ret) 2834 set_bit(FLAG_IS_OUT, &desc->flags); 2835 } 2836 trace_gpio_direction(desc_to_gpio(desc), value, ret); 2837 if (ret < 0) 2838 gpiod_err(desc, 2839 "%s: Error in set_value for open drain err %d\n", 2840 __func__, ret); 2841 } 2842 2843 /* 2844 * _gpio_set_open_source_value() - Set the open source gpio's value. 2845 * @desc: gpio descriptor whose state need to be set. 2846 * @value: Non-zero for setting it HIGH otherwise it will set to LOW. 2847 */ 2848 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value) 2849 { 2850 int ret = 0; 2851 struct gpio_chip *gc = desc->gdev->chip; 2852 int offset = gpio_chip_hwgpio(desc); 2853 2854 if (value) { 2855 ret = gc->direction_output(gc, offset, 1); 2856 if (!ret) 2857 set_bit(FLAG_IS_OUT, &desc->flags); 2858 } else { 2859 ret = gc->direction_input(gc, offset); 2860 } 2861 trace_gpio_direction(desc_to_gpio(desc), !value, ret); 2862 if (ret < 0) 2863 gpiod_err(desc, 2864 "%s: Error in set_value for open source err %d\n", 2865 __func__, ret); 2866 } 2867 2868 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value) 2869 { 2870 struct gpio_chip *gc; 2871 2872 gc = desc->gdev->chip; 2873 trace_gpio_value(desc_to_gpio(desc), 0, value); 2874 gc->set(gc, gpio_chip_hwgpio(desc), value); 2875 } 2876 2877 /* 2878 * set multiple outputs on the same chip; 2879 * use the chip's set_multiple function if available; 2880 * otherwise set the outputs sequentially; 2881 * @chip: the GPIO chip we operate on 2882 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word 2883 * defines which outputs are to be changed 2884 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word 2885 * defines the values the outputs specified by mask are to be set to 2886 */ 2887 static void gpio_chip_set_multiple(struct gpio_chip *gc, 2888 unsigned long *mask, unsigned long *bits) 2889 { 2890 if (gc->set_multiple) { 2891 gc->set_multiple(gc, mask, bits); 2892 } else { 2893 unsigned int i; 2894 2895 /* set outputs if the corresponding mask bit is set */ 2896 for_each_set_bit(i, mask, gc->ngpio) 2897 gc->set(gc, i, test_bit(i, bits)); 2898 } 2899 } 2900 2901 int gpiod_set_array_value_complex(bool raw, bool can_sleep, 2902 unsigned int array_size, 2903 struct gpio_desc **desc_array, 2904 struct gpio_array *array_info, 2905 unsigned long *value_bitmap) 2906 { 2907 int i = 0; 2908 2909 /* 2910 * Validate array_info against desc_array and its size. 2911 * It should immediately follow desc_array if both 2912 * have been obtained from the same gpiod_get_array() call. 2913 */ 2914 if (array_info && array_info->desc == desc_array && 2915 array_size <= array_info->size && 2916 (void *)array_info == desc_array + array_info->size) { 2917 if (!can_sleep) 2918 WARN_ON(array_info->chip->can_sleep); 2919 2920 if (!raw && !bitmap_empty(array_info->invert_mask, array_size)) 2921 bitmap_xor(value_bitmap, value_bitmap, 2922 array_info->invert_mask, array_size); 2923 2924 gpio_chip_set_multiple(array_info->chip, array_info->set_mask, 2925 value_bitmap); 2926 2927 i = find_first_zero_bit(array_info->set_mask, array_size); 2928 if (i == array_size) 2929 return 0; 2930 } else { 2931 array_info = NULL; 2932 } 2933 2934 while (i < array_size) { 2935 struct gpio_chip *gc = desc_array[i]->gdev->chip; 2936 DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO); 2937 DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO); 2938 unsigned long *mask, *bits; 2939 int count = 0; 2940 2941 if (likely(gc->ngpio <= FASTPATH_NGPIO)) { 2942 mask = fastpath_mask; 2943 bits = fastpath_bits; 2944 } else { 2945 gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC; 2946 2947 mask = bitmap_alloc(gc->ngpio, flags); 2948 if (!mask) 2949 return -ENOMEM; 2950 2951 bits = bitmap_alloc(gc->ngpio, flags); 2952 if (!bits) { 2953 bitmap_free(mask); 2954 return -ENOMEM; 2955 } 2956 } 2957 2958 bitmap_zero(mask, gc->ngpio); 2959 2960 if (!can_sleep) 2961 WARN_ON(gc->can_sleep); 2962 2963 do { 2964 struct gpio_desc *desc = desc_array[i]; 2965 int hwgpio = gpio_chip_hwgpio(desc); 2966 int value = test_bit(i, value_bitmap); 2967 2968 /* 2969 * Pins applicable for fast input but not for 2970 * fast output processing may have been already 2971 * inverted inside the fast path, skip them. 2972 */ 2973 if (!raw && !(array_info && 2974 test_bit(i, array_info->invert_mask)) && 2975 test_bit(FLAG_ACTIVE_LOW, &desc->flags)) 2976 value = !value; 2977 trace_gpio_value(desc_to_gpio(desc), 0, value); 2978 /* 2979 * collect all normal outputs belonging to the same chip 2980 * open drain and open source outputs are set individually 2981 */ 2982 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) { 2983 gpio_set_open_drain_value_commit(desc, value); 2984 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) { 2985 gpio_set_open_source_value_commit(desc, value); 2986 } else { 2987 __set_bit(hwgpio, mask); 2988 __assign_bit(hwgpio, bits, value); 2989 count++; 2990 } 2991 i++; 2992 2993 if (array_info) 2994 i = find_next_zero_bit(array_info->set_mask, 2995 array_size, i); 2996 } while ((i < array_size) && 2997 (desc_array[i]->gdev->chip == gc)); 2998 /* push collected bits to outputs */ 2999 if (count != 0) 3000 gpio_chip_set_multiple(gc, mask, bits); 3001 3002 if (mask != fastpath_mask) 3003 bitmap_free(mask); 3004 if (bits != fastpath_bits) 3005 bitmap_free(bits); 3006 } 3007 return 0; 3008 } 3009 3010 /** 3011 * gpiod_set_raw_value() - assign a gpio's raw value 3012 * @desc: gpio whose value will be assigned 3013 * @value: value to assign 3014 * 3015 * Set the raw value of the GPIO, i.e. the value of its physical line without 3016 * regard for its ACTIVE_LOW status. 3017 * 3018 * This function can be called from contexts where we cannot sleep, and will 3019 * complain if the GPIO chip functions potentially sleep. 3020 */ 3021 void gpiod_set_raw_value(struct gpio_desc *desc, int value) 3022 { 3023 VALIDATE_DESC_VOID(desc); 3024 /* Should be using gpiod_set_raw_value_cansleep() */ 3025 WARN_ON(desc->gdev->chip->can_sleep); 3026 gpiod_set_raw_value_commit(desc, value); 3027 } 3028 EXPORT_SYMBOL_GPL(gpiod_set_raw_value); 3029 3030 /** 3031 * gpiod_set_value_nocheck() - set a GPIO line value without checking 3032 * @desc: the descriptor to set the value on 3033 * @value: value to set 3034 * 3035 * This sets the value of a GPIO line backing a descriptor, applying 3036 * different semantic quirks like active low and open drain/source 3037 * handling. 3038 */ 3039 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value) 3040 { 3041 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) 3042 value = !value; 3043 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) 3044 gpio_set_open_drain_value_commit(desc, value); 3045 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) 3046 gpio_set_open_source_value_commit(desc, value); 3047 else 3048 gpiod_set_raw_value_commit(desc, value); 3049 } 3050 3051 /** 3052 * gpiod_set_value() - assign a gpio's value 3053 * @desc: gpio whose value will be assigned 3054 * @value: value to assign 3055 * 3056 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW, 3057 * OPEN_DRAIN and OPEN_SOURCE flags into account. 3058 * 3059 * This function can be called from contexts where we cannot sleep, and will 3060 * complain if the GPIO chip functions potentially sleep. 3061 */ 3062 void gpiod_set_value(struct gpio_desc *desc, int value) 3063 { 3064 VALIDATE_DESC_VOID(desc); 3065 /* Should be using gpiod_set_value_cansleep() */ 3066 WARN_ON(desc->gdev->chip->can_sleep); 3067 gpiod_set_value_nocheck(desc, value); 3068 } 3069 EXPORT_SYMBOL_GPL(gpiod_set_value); 3070 3071 /** 3072 * gpiod_set_raw_array_value() - assign values to an array of GPIOs 3073 * @array_size: number of elements in the descriptor array / value bitmap 3074 * @desc_array: array of GPIO descriptors whose values will be assigned 3075 * @array_info: information on applicability of fast bitmap processing path 3076 * @value_bitmap: bitmap of values to assign 3077 * 3078 * Set the raw values of the GPIOs, i.e. the values of the physical lines 3079 * without regard for their ACTIVE_LOW status. 3080 * 3081 * This function can be called from contexts where we cannot sleep, and will 3082 * complain if the GPIO chip functions potentially sleep. 3083 */ 3084 int gpiod_set_raw_array_value(unsigned int array_size, 3085 struct gpio_desc **desc_array, 3086 struct gpio_array *array_info, 3087 unsigned long *value_bitmap) 3088 { 3089 if (!desc_array) 3090 return -EINVAL; 3091 return gpiod_set_array_value_complex(true, false, array_size, 3092 desc_array, array_info, value_bitmap); 3093 } 3094 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value); 3095 3096 /** 3097 * gpiod_set_array_value() - assign values to an array of GPIOs 3098 * @array_size: number of elements in the descriptor array / value bitmap 3099 * @desc_array: array of GPIO descriptors whose values will be assigned 3100 * @array_info: information on applicability of fast bitmap processing path 3101 * @value_bitmap: bitmap of values to assign 3102 * 3103 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status 3104 * into account. 3105 * 3106 * This function can be called from contexts where we cannot sleep, and will 3107 * complain if the GPIO chip functions potentially sleep. 3108 */ 3109 int gpiod_set_array_value(unsigned int array_size, 3110 struct gpio_desc **desc_array, 3111 struct gpio_array *array_info, 3112 unsigned long *value_bitmap) 3113 { 3114 if (!desc_array) 3115 return -EINVAL; 3116 return gpiod_set_array_value_complex(false, false, array_size, 3117 desc_array, array_info, 3118 value_bitmap); 3119 } 3120 EXPORT_SYMBOL_GPL(gpiod_set_array_value); 3121 3122 /** 3123 * gpiod_cansleep() - report whether gpio value access may sleep 3124 * @desc: gpio to check 3125 * 3126 */ 3127 int gpiod_cansleep(const struct gpio_desc *desc) 3128 { 3129 VALIDATE_DESC(desc); 3130 return desc->gdev->chip->can_sleep; 3131 } 3132 EXPORT_SYMBOL_GPL(gpiod_cansleep); 3133 3134 /** 3135 * gpiod_set_consumer_name() - set the consumer name for the descriptor 3136 * @desc: gpio to set the consumer name on 3137 * @name: the new consumer name 3138 */ 3139 int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name) 3140 { 3141 VALIDATE_DESC(desc); 3142 if (name) { 3143 name = kstrdup_const(name, GFP_KERNEL); 3144 if (!name) 3145 return -ENOMEM; 3146 } 3147 3148 kfree_const(desc->label); 3149 desc_set_label(desc, name); 3150 3151 return 0; 3152 } 3153 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name); 3154 3155 /** 3156 * gpiod_to_irq() - return the IRQ corresponding to a GPIO 3157 * @desc: gpio whose IRQ will be returned (already requested) 3158 * 3159 * Return the IRQ corresponding to the passed GPIO, or an error code in case of 3160 * error. 3161 */ 3162 int gpiod_to_irq(const struct gpio_desc *desc) 3163 { 3164 struct gpio_chip *gc; 3165 int offset; 3166 3167 /* 3168 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics 3169 * requires this function to not return zero on an invalid descriptor 3170 * but rather a negative error number. 3171 */ 3172 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip) 3173 return -EINVAL; 3174 3175 gc = desc->gdev->chip; 3176 offset = gpio_chip_hwgpio(desc); 3177 if (gc->to_irq) { 3178 int retirq = gc->to_irq(gc, offset); 3179 3180 /* Zero means NO_IRQ */ 3181 if (!retirq) 3182 return -ENXIO; 3183 3184 return retirq; 3185 } 3186 #ifdef CONFIG_GPIOLIB_IRQCHIP 3187 if (gc->irq.chip) { 3188 /* 3189 * Avoid race condition with other code, which tries to lookup 3190 * an IRQ before the irqchip has been properly registered, 3191 * i.e. while gpiochip is still being brought up. 3192 */ 3193 return -EPROBE_DEFER; 3194 } 3195 #endif 3196 return -ENXIO; 3197 } 3198 EXPORT_SYMBOL_GPL(gpiod_to_irq); 3199 3200 /** 3201 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ 3202 * @gc: the chip the GPIO to lock belongs to 3203 * @offset: the offset of the GPIO to lock as IRQ 3204 * 3205 * This is used directly by GPIO drivers that want to lock down 3206 * a certain GPIO line to be used for IRQs. 3207 */ 3208 int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset) 3209 { 3210 struct gpio_desc *desc; 3211 3212 desc = gpiochip_get_desc(gc, offset); 3213 if (IS_ERR(desc)) 3214 return PTR_ERR(desc); 3215 3216 /* 3217 * If it's fast: flush the direction setting if something changed 3218 * behind our back 3219 */ 3220 if (!gc->can_sleep && gc->get_direction) { 3221 int dir = gpiod_get_direction(desc); 3222 3223 if (dir < 0) { 3224 chip_err(gc, "%s: cannot get GPIO direction\n", 3225 __func__); 3226 return dir; 3227 } 3228 } 3229 3230 /* To be valid for IRQ the line needs to be input or open drain */ 3231 if (test_bit(FLAG_IS_OUT, &desc->flags) && 3232 !test_bit(FLAG_OPEN_DRAIN, &desc->flags)) { 3233 chip_err(gc, 3234 "%s: tried to flag a GPIO set as output for IRQ\n", 3235 __func__); 3236 return -EIO; 3237 } 3238 3239 set_bit(FLAG_USED_AS_IRQ, &desc->flags); 3240 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); 3241 3242 /* 3243 * If the consumer has not set up a label (such as when the 3244 * IRQ is referenced from .to_irq()) we set up a label here 3245 * so it is clear this is used as an interrupt. 3246 */ 3247 if (!desc->label) 3248 desc_set_label(desc, "interrupt"); 3249 3250 return 0; 3251 } 3252 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq); 3253 3254 /** 3255 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ 3256 * @gc: the chip the GPIO to lock belongs to 3257 * @offset: the offset of the GPIO to lock as IRQ 3258 * 3259 * This is used directly by GPIO drivers that want to indicate 3260 * that a certain GPIO is no longer used exclusively for IRQ. 3261 */ 3262 void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset) 3263 { 3264 struct gpio_desc *desc; 3265 3266 desc = gpiochip_get_desc(gc, offset); 3267 if (IS_ERR(desc)) 3268 return; 3269 3270 clear_bit(FLAG_USED_AS_IRQ, &desc->flags); 3271 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); 3272 3273 /* If we only had this marking, erase it */ 3274 if (desc->label && !strcmp(desc->label, "interrupt")) 3275 desc_set_label(desc, NULL); 3276 } 3277 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq); 3278 3279 void gpiochip_disable_irq(struct gpio_chip *gc, unsigned int offset) 3280 { 3281 struct gpio_desc *desc = gpiochip_get_desc(gc, offset); 3282 3283 if (!IS_ERR(desc) && 3284 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) 3285 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); 3286 } 3287 EXPORT_SYMBOL_GPL(gpiochip_disable_irq); 3288 3289 void gpiochip_enable_irq(struct gpio_chip *gc, unsigned int offset) 3290 { 3291 struct gpio_desc *desc = gpiochip_get_desc(gc, offset); 3292 3293 if (!IS_ERR(desc) && 3294 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) { 3295 /* 3296 * We must not be output when using IRQ UNLESS we are 3297 * open drain. 3298 */ 3299 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags) && 3300 !test_bit(FLAG_OPEN_DRAIN, &desc->flags)); 3301 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); 3302 } 3303 } 3304 EXPORT_SYMBOL_GPL(gpiochip_enable_irq); 3305 3306 bool gpiochip_line_is_irq(struct gpio_chip *gc, unsigned int offset) 3307 { 3308 if (offset >= gc->ngpio) 3309 return false; 3310 3311 return test_bit(FLAG_USED_AS_IRQ, &gc->gpiodev->descs[offset].flags); 3312 } 3313 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq); 3314 3315 int gpiochip_reqres_irq(struct gpio_chip *gc, unsigned int offset) 3316 { 3317 int ret; 3318 3319 if (!try_module_get(gc->gpiodev->owner)) 3320 return -ENODEV; 3321 3322 ret = gpiochip_lock_as_irq(gc, offset); 3323 if (ret) { 3324 chip_err(gc, "unable to lock HW IRQ %u for IRQ\n", offset); 3325 module_put(gc->gpiodev->owner); 3326 return ret; 3327 } 3328 return 0; 3329 } 3330 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq); 3331 3332 void gpiochip_relres_irq(struct gpio_chip *gc, unsigned int offset) 3333 { 3334 gpiochip_unlock_as_irq(gc, offset); 3335 module_put(gc->gpiodev->owner); 3336 } 3337 EXPORT_SYMBOL_GPL(gpiochip_relres_irq); 3338 3339 bool gpiochip_line_is_open_drain(struct gpio_chip *gc, unsigned int offset) 3340 { 3341 if (offset >= gc->ngpio) 3342 return false; 3343 3344 return test_bit(FLAG_OPEN_DRAIN, &gc->gpiodev->descs[offset].flags); 3345 } 3346 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain); 3347 3348 bool gpiochip_line_is_open_source(struct gpio_chip *gc, unsigned int offset) 3349 { 3350 if (offset >= gc->ngpio) 3351 return false; 3352 3353 return test_bit(FLAG_OPEN_SOURCE, &gc->gpiodev->descs[offset].flags); 3354 } 3355 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source); 3356 3357 bool gpiochip_line_is_persistent(struct gpio_chip *gc, unsigned int offset) 3358 { 3359 if (offset >= gc->ngpio) 3360 return false; 3361 3362 return !test_bit(FLAG_TRANSITORY, &gc->gpiodev->descs[offset].flags); 3363 } 3364 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent); 3365 3366 /** 3367 * gpiod_get_raw_value_cansleep() - return a gpio's raw value 3368 * @desc: gpio whose value will be returned 3369 * 3370 * Return the GPIO's raw value, i.e. the value of the physical line disregarding 3371 * its ACTIVE_LOW status, or negative errno on failure. 3372 * 3373 * This function is to be called from contexts that can sleep. 3374 */ 3375 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc) 3376 { 3377 might_sleep_if(extra_checks); 3378 VALIDATE_DESC(desc); 3379 return gpiod_get_raw_value_commit(desc); 3380 } 3381 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep); 3382 3383 /** 3384 * gpiod_get_value_cansleep() - return a gpio's value 3385 * @desc: gpio whose value will be returned 3386 * 3387 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into 3388 * account, or negative errno on failure. 3389 * 3390 * This function is to be called from contexts that can sleep. 3391 */ 3392 int gpiod_get_value_cansleep(const struct gpio_desc *desc) 3393 { 3394 int value; 3395 3396 might_sleep_if(extra_checks); 3397 VALIDATE_DESC(desc); 3398 value = gpiod_get_raw_value_commit(desc); 3399 if (value < 0) 3400 return value; 3401 3402 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) 3403 value = !value; 3404 3405 return value; 3406 } 3407 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep); 3408 3409 /** 3410 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs 3411 * @array_size: number of elements in the descriptor array / value bitmap 3412 * @desc_array: array of GPIO descriptors whose values will be read 3413 * @array_info: information on applicability of fast bitmap processing path 3414 * @value_bitmap: bitmap to store the read values 3415 * 3416 * Read the raw values of the GPIOs, i.e. the values of the physical lines 3417 * without regard for their ACTIVE_LOW status. Return 0 in case of success, 3418 * else an error code. 3419 * 3420 * This function is to be called from contexts that can sleep. 3421 */ 3422 int gpiod_get_raw_array_value_cansleep(unsigned int array_size, 3423 struct gpio_desc **desc_array, 3424 struct gpio_array *array_info, 3425 unsigned long *value_bitmap) 3426 { 3427 might_sleep_if(extra_checks); 3428 if (!desc_array) 3429 return -EINVAL; 3430 return gpiod_get_array_value_complex(true, true, array_size, 3431 desc_array, array_info, 3432 value_bitmap); 3433 } 3434 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep); 3435 3436 /** 3437 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs 3438 * @array_size: number of elements in the descriptor array / value bitmap 3439 * @desc_array: array of GPIO descriptors whose values will be read 3440 * @array_info: information on applicability of fast bitmap processing path 3441 * @value_bitmap: bitmap to store the read values 3442 * 3443 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status 3444 * into account. Return 0 in case of success, else an error code. 3445 * 3446 * This function is to be called from contexts that can sleep. 3447 */ 3448 int gpiod_get_array_value_cansleep(unsigned int array_size, 3449 struct gpio_desc **desc_array, 3450 struct gpio_array *array_info, 3451 unsigned long *value_bitmap) 3452 { 3453 might_sleep_if(extra_checks); 3454 if (!desc_array) 3455 return -EINVAL; 3456 return gpiod_get_array_value_complex(false, true, array_size, 3457 desc_array, array_info, 3458 value_bitmap); 3459 } 3460 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep); 3461 3462 /** 3463 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value 3464 * @desc: gpio whose value will be assigned 3465 * @value: value to assign 3466 * 3467 * Set the raw value of the GPIO, i.e. the value of its physical line without 3468 * regard for its ACTIVE_LOW status. 3469 * 3470 * This function is to be called from contexts that can sleep. 3471 */ 3472 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) 3473 { 3474 might_sleep_if(extra_checks); 3475 VALIDATE_DESC_VOID(desc); 3476 gpiod_set_raw_value_commit(desc, value); 3477 } 3478 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep); 3479 3480 /** 3481 * gpiod_set_value_cansleep() - assign a gpio's value 3482 * @desc: gpio whose value will be assigned 3483 * @value: value to assign 3484 * 3485 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into 3486 * account 3487 * 3488 * This function is to be called from contexts that can sleep. 3489 */ 3490 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value) 3491 { 3492 might_sleep_if(extra_checks); 3493 VALIDATE_DESC_VOID(desc); 3494 gpiod_set_value_nocheck(desc, value); 3495 } 3496 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); 3497 3498 /** 3499 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs 3500 * @array_size: number of elements in the descriptor array / value bitmap 3501 * @desc_array: array of GPIO descriptors whose values will be assigned 3502 * @array_info: information on applicability of fast bitmap processing path 3503 * @value_bitmap: bitmap of values to assign 3504 * 3505 * Set the raw values of the GPIOs, i.e. the values of the physical lines 3506 * without regard for their ACTIVE_LOW status. 3507 * 3508 * This function is to be called from contexts that can sleep. 3509 */ 3510 int gpiod_set_raw_array_value_cansleep(unsigned int array_size, 3511 struct gpio_desc **desc_array, 3512 struct gpio_array *array_info, 3513 unsigned long *value_bitmap) 3514 { 3515 might_sleep_if(extra_checks); 3516 if (!desc_array) 3517 return -EINVAL; 3518 return gpiod_set_array_value_complex(true, true, array_size, desc_array, 3519 array_info, value_bitmap); 3520 } 3521 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep); 3522 3523 /** 3524 * gpiod_add_lookup_tables() - register GPIO device consumers 3525 * @tables: list of tables of consumers to register 3526 * @n: number of tables in the list 3527 */ 3528 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n) 3529 { 3530 unsigned int i; 3531 3532 mutex_lock(&gpio_lookup_lock); 3533 3534 for (i = 0; i < n; i++) 3535 list_add_tail(&tables[i]->list, &gpio_lookup_list); 3536 3537 mutex_unlock(&gpio_lookup_lock); 3538 } 3539 3540 /** 3541 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs 3542 * @array_size: number of elements in the descriptor array / value bitmap 3543 * @desc_array: array of GPIO descriptors whose values will be assigned 3544 * @array_info: information on applicability of fast bitmap processing path 3545 * @value_bitmap: bitmap of values to assign 3546 * 3547 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status 3548 * into account. 3549 * 3550 * This function is to be called from contexts that can sleep. 3551 */ 3552 int gpiod_set_array_value_cansleep(unsigned int array_size, 3553 struct gpio_desc **desc_array, 3554 struct gpio_array *array_info, 3555 unsigned long *value_bitmap) 3556 { 3557 might_sleep_if(extra_checks); 3558 if (!desc_array) 3559 return -EINVAL; 3560 return gpiod_set_array_value_complex(false, true, array_size, 3561 desc_array, array_info, 3562 value_bitmap); 3563 } 3564 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep); 3565 3566 /** 3567 * gpiod_add_lookup_table() - register GPIO device consumers 3568 * @table: table of consumers to register 3569 */ 3570 void gpiod_add_lookup_table(struct gpiod_lookup_table *table) 3571 { 3572 gpiod_add_lookup_tables(&table, 1); 3573 } 3574 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table); 3575 3576 /** 3577 * gpiod_remove_lookup_table() - unregister GPIO device consumers 3578 * @table: table of consumers to unregister 3579 */ 3580 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table) 3581 { 3582 /* Nothing to remove */ 3583 if (!table) 3584 return; 3585 3586 mutex_lock(&gpio_lookup_lock); 3587 3588 list_del(&table->list); 3589 3590 mutex_unlock(&gpio_lookup_lock); 3591 } 3592 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table); 3593 3594 /** 3595 * gpiod_add_hogs() - register a set of GPIO hogs from machine code 3596 * @hogs: table of gpio hog entries with a zeroed sentinel at the end 3597 */ 3598 void gpiod_add_hogs(struct gpiod_hog *hogs) 3599 { 3600 struct gpio_chip *gc; 3601 struct gpiod_hog *hog; 3602 3603 mutex_lock(&gpio_machine_hogs_mutex); 3604 3605 for (hog = &hogs[0]; hog->chip_label; hog++) { 3606 list_add_tail(&hog->list, &gpio_machine_hogs); 3607 3608 /* 3609 * The chip may have been registered earlier, so check if it 3610 * exists and, if so, try to hog the line now. 3611 */ 3612 gc = find_chip_by_name(hog->chip_label); 3613 if (gc) 3614 gpiochip_machine_hog(gc, hog); 3615 } 3616 3617 mutex_unlock(&gpio_machine_hogs_mutex); 3618 } 3619 EXPORT_SYMBOL_GPL(gpiod_add_hogs); 3620 3621 void gpiod_remove_hogs(struct gpiod_hog *hogs) 3622 { 3623 struct gpiod_hog *hog; 3624 3625 mutex_lock(&gpio_machine_hogs_mutex); 3626 for (hog = &hogs[0]; hog->chip_label; hog++) 3627 list_del(&hog->list); 3628 mutex_unlock(&gpio_machine_hogs_mutex); 3629 } 3630 EXPORT_SYMBOL_GPL(gpiod_remove_hogs); 3631 3632 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev) 3633 { 3634 const char *dev_id = dev ? dev_name(dev) : NULL; 3635 struct gpiod_lookup_table *table; 3636 3637 mutex_lock(&gpio_lookup_lock); 3638 3639 list_for_each_entry(table, &gpio_lookup_list, list) { 3640 if (table->dev_id && dev_id) { 3641 /* 3642 * Valid strings on both ends, must be identical to have 3643 * a match 3644 */ 3645 if (!strcmp(table->dev_id, dev_id)) 3646 goto found; 3647 } else { 3648 /* 3649 * One of the pointers is NULL, so both must be to have 3650 * a match 3651 */ 3652 if (dev_id == table->dev_id) 3653 goto found; 3654 } 3655 } 3656 table = NULL; 3657 3658 found: 3659 mutex_unlock(&gpio_lookup_lock); 3660 return table; 3661 } 3662 3663 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, 3664 unsigned int idx, unsigned long *flags) 3665 { 3666 struct gpio_desc *desc = ERR_PTR(-ENOENT); 3667 struct gpiod_lookup_table *table; 3668 struct gpiod_lookup *p; 3669 3670 table = gpiod_find_lookup_table(dev); 3671 if (!table) 3672 return desc; 3673 3674 for (p = &table->table[0]; p->key; p++) { 3675 struct gpio_chip *gc; 3676 3677 /* idx must always match exactly */ 3678 if (p->idx != idx) 3679 continue; 3680 3681 /* If the lookup entry has a con_id, require exact match */ 3682 if (p->con_id && (!con_id || strcmp(p->con_id, con_id))) 3683 continue; 3684 3685 if (p->chip_hwnum == U16_MAX) { 3686 desc = gpio_name_to_desc(p->key); 3687 if (desc) { 3688 *flags = p->flags; 3689 return desc; 3690 } 3691 3692 dev_warn(dev, "cannot find GPIO line %s, deferring\n", 3693 p->key); 3694 return ERR_PTR(-EPROBE_DEFER); 3695 } 3696 3697 gc = find_chip_by_name(p->key); 3698 3699 if (!gc) { 3700 /* 3701 * As the lookup table indicates a chip with 3702 * p->key should exist, assume it may 3703 * still appear later and let the interested 3704 * consumer be probed again or let the Deferred 3705 * Probe infrastructure handle the error. 3706 */ 3707 dev_warn(dev, "cannot find GPIO chip %s, deferring\n", 3708 p->key); 3709 return ERR_PTR(-EPROBE_DEFER); 3710 } 3711 3712 if (gc->ngpio <= p->chip_hwnum) { 3713 dev_err(dev, 3714 "requested GPIO %u (%u) is out of range [0..%u] for chip %s\n", 3715 idx, p->chip_hwnum, gc->ngpio - 1, 3716 gc->label); 3717 return ERR_PTR(-EINVAL); 3718 } 3719 3720 desc = gpiochip_get_desc(gc, p->chip_hwnum); 3721 *flags = p->flags; 3722 3723 return desc; 3724 } 3725 3726 return desc; 3727 } 3728 3729 static int platform_gpio_count(struct device *dev, const char *con_id) 3730 { 3731 struct gpiod_lookup_table *table; 3732 struct gpiod_lookup *p; 3733 unsigned int count = 0; 3734 3735 table = gpiod_find_lookup_table(dev); 3736 if (!table) 3737 return -ENOENT; 3738 3739 for (p = &table->table[0]; p->key; p++) { 3740 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) || 3741 (!con_id && !p->con_id)) 3742 count++; 3743 } 3744 if (!count) 3745 return -ENOENT; 3746 3747 return count; 3748 } 3749 3750 /** 3751 * fwnode_gpiod_get_index - obtain a GPIO from firmware node 3752 * @fwnode: handle of the firmware node 3753 * @con_id: function within the GPIO consumer 3754 * @index: index of the GPIO to obtain for the consumer 3755 * @flags: GPIO initialization flags 3756 * @label: label to attach to the requested GPIO 3757 * 3758 * This function can be used for drivers that get their configuration 3759 * from opaque firmware. 3760 * 3761 * The function properly finds the corresponding GPIO using whatever is the 3762 * underlying firmware interface and then makes sure that the GPIO 3763 * descriptor is requested before it is returned to the caller. 3764 * 3765 * Returns: 3766 * On successful request the GPIO pin is configured in accordance with 3767 * provided @flags. 3768 * 3769 * In case of error an ERR_PTR() is returned. 3770 */ 3771 struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode, 3772 const char *con_id, int index, 3773 enum gpiod_flags flags, 3774 const char *label) 3775 { 3776 struct gpio_desc *desc; 3777 char prop_name[32]; /* 32 is max size of property name */ 3778 unsigned int i; 3779 3780 for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { 3781 if (con_id) 3782 snprintf(prop_name, sizeof(prop_name), "%s-%s", 3783 con_id, gpio_suffixes[i]); 3784 else 3785 snprintf(prop_name, sizeof(prop_name), "%s", 3786 gpio_suffixes[i]); 3787 3788 desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags, 3789 label); 3790 if (!gpiod_not_found(desc)) 3791 break; 3792 } 3793 3794 return desc; 3795 } 3796 EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index); 3797 3798 /** 3799 * gpiod_count - return the number of GPIOs associated with a device / function 3800 * or -ENOENT if no GPIO has been assigned to the requested function 3801 * @dev: GPIO consumer, can be NULL for system-global GPIOs 3802 * @con_id: function within the GPIO consumer 3803 */ 3804 int gpiod_count(struct device *dev, const char *con_id) 3805 { 3806 const struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL; 3807 int count = -ENOENT; 3808 3809 if (is_of_node(fwnode)) 3810 count = of_gpio_get_count(dev, con_id); 3811 else if (is_acpi_node(fwnode)) 3812 count = acpi_gpio_count(dev, con_id); 3813 3814 if (count < 0) 3815 count = platform_gpio_count(dev, con_id); 3816 3817 return count; 3818 } 3819 EXPORT_SYMBOL_GPL(gpiod_count); 3820 3821 /** 3822 * gpiod_get - obtain a GPIO for a given GPIO function 3823 * @dev: GPIO consumer, can be NULL for system-global GPIOs 3824 * @con_id: function within the GPIO consumer 3825 * @flags: optional GPIO initialization flags 3826 * 3827 * Return the GPIO descriptor corresponding to the function con_id of device 3828 * dev, -ENOENT if no GPIO has been assigned to the requested function, or 3829 * another IS_ERR() code if an error occurred while trying to acquire the GPIO. 3830 */ 3831 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id, 3832 enum gpiod_flags flags) 3833 { 3834 return gpiod_get_index(dev, con_id, 0, flags); 3835 } 3836 EXPORT_SYMBOL_GPL(gpiod_get); 3837 3838 /** 3839 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function 3840 * @dev: GPIO consumer, can be NULL for system-global GPIOs 3841 * @con_id: function within the GPIO consumer 3842 * @flags: optional GPIO initialization flags 3843 * 3844 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to 3845 * the requested function it will return NULL. This is convenient for drivers 3846 * that need to handle optional GPIOs. 3847 */ 3848 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev, 3849 const char *con_id, 3850 enum gpiod_flags flags) 3851 { 3852 return gpiod_get_index_optional(dev, con_id, 0, flags); 3853 } 3854 EXPORT_SYMBOL_GPL(gpiod_get_optional); 3855 3856 3857 /** 3858 * gpiod_configure_flags - helper function to configure a given GPIO 3859 * @desc: gpio whose value will be assigned 3860 * @con_id: function within the GPIO consumer 3861 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from 3862 * of_find_gpio() or of_get_gpio_hog() 3863 * @dflags: gpiod_flags - optional GPIO initialization flags 3864 * 3865 * Return 0 on success, -ENOENT if no GPIO has been assigned to the 3866 * requested function and/or index, or another IS_ERR() code if an error 3867 * occurred while trying to acquire the GPIO. 3868 */ 3869 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, 3870 unsigned long lflags, enum gpiod_flags dflags) 3871 { 3872 int ret; 3873 3874 if (lflags & GPIO_ACTIVE_LOW) 3875 set_bit(FLAG_ACTIVE_LOW, &desc->flags); 3876 3877 if (lflags & GPIO_OPEN_DRAIN) 3878 set_bit(FLAG_OPEN_DRAIN, &desc->flags); 3879 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) { 3880 /* 3881 * This enforces open drain mode from the consumer side. 3882 * This is necessary for some busses like I2C, but the lookup 3883 * should *REALLY* have specified them as open drain in the 3884 * first place, so print a little warning here. 3885 */ 3886 set_bit(FLAG_OPEN_DRAIN, &desc->flags); 3887 gpiod_warn(desc, 3888 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n"); 3889 } 3890 3891 if (lflags & GPIO_OPEN_SOURCE) 3892 set_bit(FLAG_OPEN_SOURCE, &desc->flags); 3893 3894 if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) { 3895 gpiod_err(desc, 3896 "both pull-up and pull-down enabled, invalid configuration\n"); 3897 return -EINVAL; 3898 } 3899 3900 if (lflags & GPIO_PULL_UP) 3901 set_bit(FLAG_PULL_UP, &desc->flags); 3902 else if (lflags & GPIO_PULL_DOWN) 3903 set_bit(FLAG_PULL_DOWN, &desc->flags); 3904 3905 ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY)); 3906 if (ret < 0) 3907 return ret; 3908 3909 /* No particular flag request, return here... */ 3910 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) { 3911 gpiod_dbg(desc, "no flags found for %s\n", con_id); 3912 return 0; 3913 } 3914 3915 /* Process flags */ 3916 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT) 3917 ret = gpiod_direction_output(desc, 3918 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL)); 3919 else 3920 ret = gpiod_direction_input(desc); 3921 3922 return ret; 3923 } 3924 3925 /** 3926 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function 3927 * @dev: GPIO consumer, can be NULL for system-global GPIOs 3928 * @con_id: function within the GPIO consumer 3929 * @idx: index of the GPIO to obtain in the consumer 3930 * @flags: optional GPIO initialization flags 3931 * 3932 * This variant of gpiod_get() allows to access GPIOs other than the first 3933 * defined one for functions that define several GPIOs. 3934 * 3935 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the 3936 * requested function and/or index, or another IS_ERR() code if an error 3937 * occurred while trying to acquire the GPIO. 3938 */ 3939 struct gpio_desc *__must_check gpiod_get_index(struct device *dev, 3940 const char *con_id, 3941 unsigned int idx, 3942 enum gpiod_flags flags) 3943 { 3944 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT; 3945 struct gpio_desc *desc = NULL; 3946 int ret; 3947 /* Maybe we have a device name, maybe not */ 3948 const char *devname = dev ? dev_name(dev) : "?"; 3949 const struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL; 3950 3951 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); 3952 3953 /* Using device tree? */ 3954 if (is_of_node(fwnode)) { 3955 dev_dbg(dev, "using device tree for GPIO lookup\n"); 3956 desc = of_find_gpio(dev, con_id, idx, &lookupflags); 3957 } else if (is_acpi_node(fwnode)) { 3958 dev_dbg(dev, "using ACPI for GPIO lookup\n"); 3959 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags); 3960 } 3961 3962 /* 3963 * Either we are not using DT or ACPI, or their lookup did not return 3964 * a result. In that case, use platform lookup as a fallback. 3965 */ 3966 if (!desc || gpiod_not_found(desc)) { 3967 dev_dbg(dev, "using lookup tables for GPIO lookup\n"); 3968 desc = gpiod_find(dev, con_id, idx, &lookupflags); 3969 } 3970 3971 if (IS_ERR(desc)) { 3972 dev_dbg(dev, "No GPIO consumer %s found\n", con_id); 3973 return desc; 3974 } 3975 3976 /* 3977 * If a connection label was passed use that, else attempt to use 3978 * the device name as label 3979 */ 3980 ret = gpiod_request(desc, con_id ?: devname); 3981 if (ret) { 3982 if (!(ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE)) 3983 return ERR_PTR(ret); 3984 3985 /* 3986 * This happens when there are several consumers for 3987 * the same GPIO line: we just return here without 3988 * further initialization. It is a bit of a hack. 3989 * This is necessary to support fixed regulators. 3990 * 3991 * FIXME: Make this more sane and safe. 3992 */ 3993 dev_info(dev, "nonexclusive access to GPIO for %s\n", con_id ?: devname); 3994 return desc; 3995 } 3996 3997 ret = gpiod_configure_flags(desc, con_id, lookupflags, flags); 3998 if (ret < 0) { 3999 dev_dbg(dev, "setup of GPIO %s failed\n", con_id); 4000 gpiod_put(desc); 4001 return ERR_PTR(ret); 4002 } 4003 4004 blocking_notifier_call_chain(&desc->gdev->notifier, 4005 GPIOLINE_CHANGED_REQUESTED, desc); 4006 4007 return desc; 4008 } 4009 EXPORT_SYMBOL_GPL(gpiod_get_index); 4010 4011 /** 4012 * fwnode_get_named_gpiod - obtain a GPIO from firmware node 4013 * @fwnode: handle of the firmware node 4014 * @propname: name of the firmware property representing the GPIO 4015 * @index: index of the GPIO to obtain for the consumer 4016 * @dflags: GPIO initialization flags 4017 * @label: label to attach to the requested GPIO 4018 * 4019 * This function can be used for drivers that get their configuration 4020 * from opaque firmware. 4021 * 4022 * The function properly finds the corresponding GPIO using whatever is the 4023 * underlying firmware interface and then makes sure that the GPIO 4024 * descriptor is requested before it is returned to the caller. 4025 * 4026 * Returns: 4027 * On successful request the GPIO pin is configured in accordance with 4028 * provided @dflags. 4029 * 4030 * In case of error an ERR_PTR() is returned. 4031 */ 4032 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, 4033 const char *propname, int index, 4034 enum gpiod_flags dflags, 4035 const char *label) 4036 { 4037 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT; 4038 struct gpio_desc *desc = ERR_PTR(-ENODEV); 4039 int ret; 4040 4041 if (is_of_node(fwnode)) { 4042 desc = gpiod_get_from_of_node(to_of_node(fwnode), 4043 propname, index, 4044 dflags, 4045 label); 4046 return desc; 4047 } else if (is_acpi_node(fwnode)) { 4048 struct acpi_gpio_info info; 4049 4050 desc = acpi_node_get_gpiod(fwnode, propname, index, &info); 4051 if (IS_ERR(desc)) 4052 return desc; 4053 4054 acpi_gpio_update_gpiod_flags(&dflags, &info); 4055 acpi_gpio_update_gpiod_lookup_flags(&lflags, &info); 4056 } else 4057 return ERR_PTR(-EINVAL); 4058 4059 /* Currently only ACPI takes this path */ 4060 ret = gpiod_request(desc, label); 4061 if (ret) 4062 return ERR_PTR(ret); 4063 4064 ret = gpiod_configure_flags(desc, propname, lflags, dflags); 4065 if (ret < 0) { 4066 gpiod_put(desc); 4067 return ERR_PTR(ret); 4068 } 4069 4070 blocking_notifier_call_chain(&desc->gdev->notifier, 4071 GPIOLINE_CHANGED_REQUESTED, desc); 4072 4073 return desc; 4074 } 4075 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod); 4076 4077 /** 4078 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO 4079 * function 4080 * @dev: GPIO consumer, can be NULL for system-global GPIOs 4081 * @con_id: function within the GPIO consumer 4082 * @index: index of the GPIO to obtain in the consumer 4083 * @flags: optional GPIO initialization flags 4084 * 4085 * This is equivalent to gpiod_get_index(), except that when no GPIO with the 4086 * specified index was assigned to the requested function it will return NULL. 4087 * This is convenient for drivers that need to handle optional GPIOs. 4088 */ 4089 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev, 4090 const char *con_id, 4091 unsigned int index, 4092 enum gpiod_flags flags) 4093 { 4094 struct gpio_desc *desc; 4095 4096 desc = gpiod_get_index(dev, con_id, index, flags); 4097 if (gpiod_not_found(desc)) 4098 return NULL; 4099 4100 return desc; 4101 } 4102 EXPORT_SYMBOL_GPL(gpiod_get_index_optional); 4103 4104 /** 4105 * gpiod_hog - Hog the specified GPIO desc given the provided flags 4106 * @desc: gpio whose value will be assigned 4107 * @name: gpio line name 4108 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from 4109 * of_find_gpio() or of_get_gpio_hog() 4110 * @dflags: gpiod_flags - optional GPIO initialization flags 4111 */ 4112 int gpiod_hog(struct gpio_desc *desc, const char *name, 4113 unsigned long lflags, enum gpiod_flags dflags) 4114 { 4115 struct gpio_chip *gc; 4116 struct gpio_desc *local_desc; 4117 int hwnum; 4118 int ret; 4119 4120 gc = gpiod_to_chip(desc); 4121 hwnum = gpio_chip_hwgpio(desc); 4122 4123 local_desc = gpiochip_request_own_desc(gc, hwnum, name, 4124 lflags, dflags); 4125 if (IS_ERR(local_desc)) { 4126 ret = PTR_ERR(local_desc); 4127 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n", 4128 name, gc->label, hwnum, ret); 4129 return ret; 4130 } 4131 4132 /* Mark GPIO as hogged so it can be identified and removed later */ 4133 set_bit(FLAG_IS_HOGGED, &desc->flags); 4134 4135 gpiod_info(desc, "hogged as %s%s\n", 4136 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input", 4137 (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? 4138 (dflags & GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low" : ""); 4139 4140 return 0; 4141 } 4142 4143 /** 4144 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog 4145 * @gc: gpio chip to act on 4146 */ 4147 static void gpiochip_free_hogs(struct gpio_chip *gc) 4148 { 4149 struct gpio_desc *desc; 4150 int id; 4151 4152 for_each_gpio_desc_with_flag(id, gc, desc, FLAG_IS_HOGGED) 4153 gpiochip_free_own_desc(desc); 4154 } 4155 4156 /** 4157 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function 4158 * @dev: GPIO consumer, can be NULL for system-global GPIOs 4159 * @con_id: function within the GPIO consumer 4160 * @flags: optional GPIO initialization flags 4161 * 4162 * This function acquires all the GPIOs defined under a given function. 4163 * 4164 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if 4165 * no GPIO has been assigned to the requested function, or another IS_ERR() 4166 * code if an error occurred while trying to acquire the GPIOs. 4167 */ 4168 struct gpio_descs *__must_check gpiod_get_array(struct device *dev, 4169 const char *con_id, 4170 enum gpiod_flags flags) 4171 { 4172 struct gpio_desc *desc; 4173 struct gpio_descs *descs; 4174 struct gpio_array *array_info = NULL; 4175 struct gpio_chip *gc; 4176 int count, bitmap_size; 4177 4178 count = gpiod_count(dev, con_id); 4179 if (count < 0) 4180 return ERR_PTR(count); 4181 4182 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL); 4183 if (!descs) 4184 return ERR_PTR(-ENOMEM); 4185 4186 for (descs->ndescs = 0; descs->ndescs < count; ) { 4187 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags); 4188 if (IS_ERR(desc)) { 4189 gpiod_put_array(descs); 4190 return ERR_CAST(desc); 4191 } 4192 4193 descs->desc[descs->ndescs] = desc; 4194 4195 gc = gpiod_to_chip(desc); 4196 /* 4197 * If pin hardware number of array member 0 is also 0, select 4198 * its chip as a candidate for fast bitmap processing path. 4199 */ 4200 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) { 4201 struct gpio_descs *array; 4202 4203 bitmap_size = BITS_TO_LONGS(gc->ngpio > count ? 4204 gc->ngpio : count); 4205 4206 array = kzalloc(struct_size(descs, desc, count) + 4207 struct_size(array_info, invert_mask, 4208 3 * bitmap_size), GFP_KERNEL); 4209 if (!array) { 4210 gpiod_put_array(descs); 4211 return ERR_PTR(-ENOMEM); 4212 } 4213 4214 memcpy(array, descs, 4215 struct_size(descs, desc, descs->ndescs + 1)); 4216 kfree(descs); 4217 4218 descs = array; 4219 array_info = (void *)(descs->desc + count); 4220 array_info->get_mask = array_info->invert_mask + 4221 bitmap_size; 4222 array_info->set_mask = array_info->get_mask + 4223 bitmap_size; 4224 4225 array_info->desc = descs->desc; 4226 array_info->size = count; 4227 array_info->chip = gc; 4228 bitmap_set(array_info->get_mask, descs->ndescs, 4229 count - descs->ndescs); 4230 bitmap_set(array_info->set_mask, descs->ndescs, 4231 count - descs->ndescs); 4232 descs->info = array_info; 4233 } 4234 /* Unmark array members which don't belong to the 'fast' chip */ 4235 if (array_info && array_info->chip != gc) { 4236 __clear_bit(descs->ndescs, array_info->get_mask); 4237 __clear_bit(descs->ndescs, array_info->set_mask); 4238 } 4239 /* 4240 * Detect array members which belong to the 'fast' chip 4241 * but their pins are not in hardware order. 4242 */ 4243 else if (array_info && 4244 gpio_chip_hwgpio(desc) != descs->ndescs) { 4245 /* 4246 * Don't use fast path if all array members processed so 4247 * far belong to the same chip as this one but its pin 4248 * hardware number is different from its array index. 4249 */ 4250 if (bitmap_full(array_info->get_mask, descs->ndescs)) { 4251 array_info = NULL; 4252 } else { 4253 __clear_bit(descs->ndescs, 4254 array_info->get_mask); 4255 __clear_bit(descs->ndescs, 4256 array_info->set_mask); 4257 } 4258 } else if (array_info) { 4259 /* Exclude open drain or open source from fast output */ 4260 if (gpiochip_line_is_open_drain(gc, descs->ndescs) || 4261 gpiochip_line_is_open_source(gc, descs->ndescs)) 4262 __clear_bit(descs->ndescs, 4263 array_info->set_mask); 4264 /* Identify 'fast' pins which require invertion */ 4265 if (gpiod_is_active_low(desc)) 4266 __set_bit(descs->ndescs, 4267 array_info->invert_mask); 4268 } 4269 4270 descs->ndescs++; 4271 } 4272 if (array_info) 4273 dev_dbg(dev, 4274 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n", 4275 array_info->chip->label, array_info->size, 4276 *array_info->get_mask, *array_info->set_mask, 4277 *array_info->invert_mask); 4278 return descs; 4279 } 4280 EXPORT_SYMBOL_GPL(gpiod_get_array); 4281 4282 /** 4283 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO 4284 * function 4285 * @dev: GPIO consumer, can be NULL for system-global GPIOs 4286 * @con_id: function within the GPIO consumer 4287 * @flags: optional GPIO initialization flags 4288 * 4289 * This is equivalent to gpiod_get_array(), except that when no GPIO was 4290 * assigned to the requested function it will return NULL. 4291 */ 4292 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev, 4293 const char *con_id, 4294 enum gpiod_flags flags) 4295 { 4296 struct gpio_descs *descs; 4297 4298 descs = gpiod_get_array(dev, con_id, flags); 4299 if (gpiod_not_found(descs)) 4300 return NULL; 4301 4302 return descs; 4303 } 4304 EXPORT_SYMBOL_GPL(gpiod_get_array_optional); 4305 4306 /** 4307 * gpiod_put - dispose of a GPIO descriptor 4308 * @desc: GPIO descriptor to dispose of 4309 * 4310 * No descriptor can be used after gpiod_put() has been called on it. 4311 */ 4312 void gpiod_put(struct gpio_desc *desc) 4313 { 4314 if (desc) 4315 gpiod_free(desc); 4316 } 4317 EXPORT_SYMBOL_GPL(gpiod_put); 4318 4319 /** 4320 * gpiod_put_array - dispose of multiple GPIO descriptors 4321 * @descs: struct gpio_descs containing an array of descriptors 4322 */ 4323 void gpiod_put_array(struct gpio_descs *descs) 4324 { 4325 unsigned int i; 4326 4327 for (i = 0; i < descs->ndescs; i++) 4328 gpiod_put(descs->desc[i]); 4329 4330 kfree(descs); 4331 } 4332 EXPORT_SYMBOL_GPL(gpiod_put_array); 4333 4334 4335 static int gpio_bus_match(struct device *dev, struct device_driver *drv) 4336 { 4337 struct fwnode_handle *fwnode = dev_fwnode(dev); 4338 4339 /* 4340 * Only match if the fwnode doesn't already have a proper struct device 4341 * created for it. 4342 */ 4343 if (fwnode && fwnode->dev != dev) 4344 return 0; 4345 return 1; 4346 } 4347 4348 static int gpio_stub_drv_probe(struct device *dev) 4349 { 4350 /* 4351 * The DT node of some GPIO chips have a "compatible" property, but 4352 * never have a struct device added and probed by a driver to register 4353 * the GPIO chip with gpiolib. In such cases, fw_devlink=on will cause 4354 * the consumers of the GPIO chip to get probe deferred forever because 4355 * they will be waiting for a device associated with the GPIO chip 4356 * firmware node to get added and bound to a driver. 4357 * 4358 * To allow these consumers to probe, we associate the struct 4359 * gpio_device of the GPIO chip with the firmware node and then simply 4360 * bind it to this stub driver. 4361 */ 4362 return 0; 4363 } 4364 4365 static struct device_driver gpio_stub_drv = { 4366 .name = "gpio_stub_drv", 4367 .bus = &gpio_bus_type, 4368 .probe = gpio_stub_drv_probe, 4369 }; 4370 4371 static int __init gpiolib_dev_init(void) 4372 { 4373 int ret; 4374 4375 /* Register GPIO sysfs bus */ 4376 ret = bus_register(&gpio_bus_type); 4377 if (ret < 0) { 4378 pr_err("gpiolib: could not register GPIO bus type\n"); 4379 return ret; 4380 } 4381 4382 ret = driver_register(&gpio_stub_drv); 4383 if (ret < 0) { 4384 pr_err("gpiolib: could not register GPIO stub driver\n"); 4385 bus_unregister(&gpio_bus_type); 4386 return ret; 4387 } 4388 4389 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME); 4390 if (ret < 0) { 4391 pr_err("gpiolib: failed to allocate char dev region\n"); 4392 driver_unregister(&gpio_stub_drv); 4393 bus_unregister(&gpio_bus_type); 4394 return ret; 4395 } 4396 4397 gpiolib_initialized = true; 4398 gpiochip_setup_devs(); 4399 4400 #if IS_ENABLED(CONFIG_OF_DYNAMIC) && IS_ENABLED(CONFIG_OF_GPIO) 4401 WARN_ON(of_reconfig_notifier_register(&gpio_of_notifier)); 4402 #endif /* CONFIG_OF_DYNAMIC && CONFIG_OF_GPIO */ 4403 4404 return ret; 4405 } 4406 core_initcall(gpiolib_dev_init); 4407 4408 #ifdef CONFIG_DEBUG_FS 4409 4410 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev) 4411 { 4412 unsigned i; 4413 struct gpio_chip *gc = gdev->chip; 4414 unsigned gpio = gdev->base; 4415 struct gpio_desc *gdesc = &gdev->descs[0]; 4416 bool is_out; 4417 bool is_irq; 4418 bool active_low; 4419 4420 for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) { 4421 if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) { 4422 if (gdesc->name) { 4423 seq_printf(s, " gpio-%-3d (%-20.20s)\n", 4424 gpio, gdesc->name); 4425 } 4426 continue; 4427 } 4428 4429 gpiod_get_direction(gdesc); 4430 is_out = test_bit(FLAG_IS_OUT, &gdesc->flags); 4431 is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags); 4432 active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags); 4433 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s", 4434 gpio, gdesc->name ? gdesc->name : "", gdesc->label, 4435 is_out ? "out" : "in ", 4436 gc->get ? (gc->get(gc, i) ? "hi" : "lo") : "? ", 4437 is_irq ? "IRQ " : "", 4438 active_low ? "ACTIVE LOW" : ""); 4439 seq_printf(s, "\n"); 4440 } 4441 } 4442 4443 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) 4444 { 4445 unsigned long flags; 4446 struct gpio_device *gdev = NULL; 4447 loff_t index = *pos; 4448 4449 s->private = ""; 4450 4451 spin_lock_irqsave(&gpio_lock, flags); 4452 list_for_each_entry(gdev, &gpio_devices, list) 4453 if (index-- == 0) { 4454 spin_unlock_irqrestore(&gpio_lock, flags); 4455 return gdev; 4456 } 4457 spin_unlock_irqrestore(&gpio_lock, flags); 4458 4459 return NULL; 4460 } 4461 4462 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos) 4463 { 4464 unsigned long flags; 4465 struct gpio_device *gdev = v; 4466 void *ret = NULL; 4467 4468 spin_lock_irqsave(&gpio_lock, flags); 4469 if (list_is_last(&gdev->list, &gpio_devices)) 4470 ret = NULL; 4471 else 4472 ret = list_first_entry(&gdev->list, struct gpio_device, list); 4473 spin_unlock_irqrestore(&gpio_lock, flags); 4474 4475 s->private = "\n"; 4476 ++*pos; 4477 4478 return ret; 4479 } 4480 4481 static void gpiolib_seq_stop(struct seq_file *s, void *v) 4482 { 4483 } 4484 4485 static int gpiolib_seq_show(struct seq_file *s, void *v) 4486 { 4487 struct gpio_device *gdev = v; 4488 struct gpio_chip *gc = gdev->chip; 4489 struct device *parent; 4490 4491 if (!gc) { 4492 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private, 4493 dev_name(&gdev->dev)); 4494 return 0; 4495 } 4496 4497 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private, 4498 dev_name(&gdev->dev), 4499 gdev->base, gdev->base + gdev->ngpio - 1); 4500 parent = gc->parent; 4501 if (parent) 4502 seq_printf(s, ", parent: %s/%s", 4503 parent->bus ? parent->bus->name : "no-bus", 4504 dev_name(parent)); 4505 if (gc->label) 4506 seq_printf(s, ", %s", gc->label); 4507 if (gc->can_sleep) 4508 seq_printf(s, ", can sleep"); 4509 seq_printf(s, ":\n"); 4510 4511 if (gc->dbg_show) 4512 gc->dbg_show(s, gc); 4513 else 4514 gpiolib_dbg_show(s, gdev); 4515 4516 return 0; 4517 } 4518 4519 static const struct seq_operations gpiolib_sops = { 4520 .start = gpiolib_seq_start, 4521 .next = gpiolib_seq_next, 4522 .stop = gpiolib_seq_stop, 4523 .show = gpiolib_seq_show, 4524 }; 4525 DEFINE_SEQ_ATTRIBUTE(gpiolib); 4526 4527 static int __init gpiolib_debugfs_init(void) 4528 { 4529 /* /sys/kernel/debug/gpio */ 4530 debugfs_create_file("gpio", 0444, NULL, NULL, &gpiolib_fops); 4531 return 0; 4532 } 4533 subsys_initcall(gpiolib_debugfs_init); 4534 4535 #endif /* DEBUG_FS */ 4536