1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/bitmap.h> 3 #include <linux/kernel.h> 4 #include <linux/module.h> 5 #include <linux/interrupt.h> 6 #include <linux/irq.h> 7 #include <linux/spinlock.h> 8 #include <linux/list.h> 9 #include <linux/device.h> 10 #include <linux/err.h> 11 #include <linux/debugfs.h> 12 #include <linux/seq_file.h> 13 #include <linux/gpio.h> 14 #include <linux/idr.h> 15 #include <linux/slab.h> 16 #include <linux/acpi.h> 17 #include <linux/gpio/driver.h> 18 #include <linux/gpio/machine.h> 19 #include <linux/pinctrl/consumer.h> 20 #include <linux/cdev.h> 21 #include <linux/fs.h> 22 #include <linux/uaccess.h> 23 #include <linux/compat.h> 24 #include <linux/anon_inodes.h> 25 #include <linux/file.h> 26 #include <linux/kfifo.h> 27 #include <linux/poll.h> 28 #include <linux/timekeeping.h> 29 #include <uapi/linux/gpio.h> 30 31 #include "gpiolib.h" 32 #include "gpiolib-of.h" 33 #include "gpiolib-acpi.h" 34 35 #define CREATE_TRACE_POINTS 36 #include <trace/events/gpio.h> 37 38 /* Implementation infrastructure for GPIO interfaces. 39 * 40 * The GPIO programming interface allows for inlining speed-critical 41 * get/set operations for common cases, so that access to SOC-integrated 42 * GPIOs can sometimes cost only an instruction or two per bit. 43 */ 44 45 46 /* When debugging, extend minimal trust to callers and platform code. 47 * Also emit diagnostic messages that may help initial bringup, when 48 * board setup or driver bugs are most common. 49 * 50 * Otherwise, minimize overhead in what may be bitbanging codepaths. 51 */ 52 #ifdef DEBUG 53 #define extra_checks 1 54 #else 55 #define extra_checks 0 56 #endif 57 58 /* Device and char device-related information */ 59 static DEFINE_IDA(gpio_ida); 60 static dev_t gpio_devt; 61 #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */ 62 static struct bus_type gpio_bus_type = { 63 .name = "gpio", 64 }; 65 66 /* 67 * Number of GPIOs to use for the fast path in set array 68 */ 69 #define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT 70 71 /* gpio_lock prevents conflicts during gpio_desc[] table updates. 72 * While any GPIO is requested, its gpio_chip is not removable; 73 * each GPIO's "requested" flag serves as a lock and refcount. 74 */ 75 DEFINE_SPINLOCK(gpio_lock); 76 77 static DEFINE_MUTEX(gpio_lookup_lock); 78 static LIST_HEAD(gpio_lookup_list); 79 LIST_HEAD(gpio_devices); 80 81 static DEFINE_MUTEX(gpio_machine_hogs_mutex); 82 static LIST_HEAD(gpio_machine_hogs); 83 84 static void gpiochip_free_hogs(struct gpio_chip *chip); 85 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip, 86 struct lock_class_key *lock_key, 87 struct lock_class_key *request_key); 88 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip); 89 static int gpiochip_irqchip_init_hw(struct gpio_chip *gpiochip); 90 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip); 91 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip); 92 93 static bool gpiolib_initialized; 94 95 static inline void desc_set_label(struct gpio_desc *d, const char *label) 96 { 97 d->label = label; 98 } 99 100 /** 101 * gpio_to_desc - Convert a GPIO number to its descriptor 102 * @gpio: global GPIO number 103 * 104 * Returns: 105 * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO 106 * with the given number exists in the system. 107 */ 108 struct gpio_desc *gpio_to_desc(unsigned gpio) 109 { 110 struct gpio_device *gdev; 111 unsigned long flags; 112 113 spin_lock_irqsave(&gpio_lock, flags); 114 115 list_for_each_entry(gdev, &gpio_devices, list) { 116 if (gdev->base <= gpio && 117 gdev->base + gdev->ngpio > gpio) { 118 spin_unlock_irqrestore(&gpio_lock, flags); 119 return &gdev->descs[gpio - gdev->base]; 120 } 121 } 122 123 spin_unlock_irqrestore(&gpio_lock, flags); 124 125 if (!gpio_is_valid(gpio)) 126 WARN(1, "invalid GPIO %d\n", gpio); 127 128 return NULL; 129 } 130 EXPORT_SYMBOL_GPL(gpio_to_desc); 131 132 /** 133 * gpiochip_get_desc - get the GPIO descriptor corresponding to the given 134 * hardware number for this chip 135 * @chip: GPIO chip 136 * @hwnum: hardware number of the GPIO for this chip 137 * 138 * Returns: 139 * A pointer to the GPIO descriptor or %ERR_PTR(-EINVAL) if no GPIO exists 140 * in the given chip for the specified hardware number. 141 */ 142 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, 143 u16 hwnum) 144 { 145 struct gpio_device *gdev = chip->gpiodev; 146 147 if (hwnum >= gdev->ngpio) 148 return ERR_PTR(-EINVAL); 149 150 return &gdev->descs[hwnum]; 151 } 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 *chip; 217 unsigned offset; 218 int ret; 219 220 chip = gpiod_to_chip(desc); 221 offset = gpio_chip_hwgpio(desc); 222 223 if (!chip->get_direction) 224 return -ENOTSUPP; 225 226 ret = chip->get_direction(chip, offset); 227 if (ret > 0) { 228 /* GPIOF_DIR_IN, or other positive */ 229 ret = 1; 230 clear_bit(FLAG_IS_OUT, &desc->flags); 231 } 232 if (ret == 0) { 233 /* GPIOF_DIR_OUT */ 234 set_bit(FLAG_IS_OUT, &desc->flags); 235 } 236 return ret; 237 } 238 EXPORT_SYMBOL_GPL(gpiod_get_direction); 239 240 /* 241 * Add a new chip to the global chips list, keeping the list of chips sorted 242 * by range(means [base, base + ngpio - 1]) order. 243 * 244 * Return -EBUSY if the new chip overlaps with some other chip's integer 245 * space. 246 */ 247 static int gpiodev_add_to_list(struct gpio_device *gdev) 248 { 249 struct gpio_device *prev, *next; 250 251 if (list_empty(&gpio_devices)) { 252 /* initial entry in list */ 253 list_add_tail(&gdev->list, &gpio_devices); 254 return 0; 255 } 256 257 next = list_entry(gpio_devices.next, struct gpio_device, list); 258 if (gdev->base + gdev->ngpio <= next->base) { 259 /* add before first entry */ 260 list_add(&gdev->list, &gpio_devices); 261 return 0; 262 } 263 264 prev = list_entry(gpio_devices.prev, struct gpio_device, list); 265 if (prev->base + prev->ngpio <= gdev->base) { 266 /* add behind last entry */ 267 list_add_tail(&gdev->list, &gpio_devices); 268 return 0; 269 } 270 271 list_for_each_entry_safe(prev, next, &gpio_devices, list) { 272 /* at the end of the list */ 273 if (&next->list == &gpio_devices) 274 break; 275 276 /* add between prev and next */ 277 if (prev->base + prev->ngpio <= gdev->base 278 && gdev->base + gdev->ngpio <= next->base) { 279 list_add(&gdev->list, &prev->list); 280 return 0; 281 } 282 } 283 284 dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n"); 285 return -EBUSY; 286 } 287 288 /* 289 * Convert a GPIO name to its descriptor 290 */ 291 static struct gpio_desc *gpio_name_to_desc(const char * const name) 292 { 293 struct gpio_device *gdev; 294 unsigned long flags; 295 296 spin_lock_irqsave(&gpio_lock, flags); 297 298 list_for_each_entry(gdev, &gpio_devices, list) { 299 int i; 300 301 for (i = 0; i != gdev->ngpio; ++i) { 302 struct gpio_desc *desc = &gdev->descs[i]; 303 304 if (!desc->name || !name) 305 continue; 306 307 if (!strcmp(desc->name, name)) { 308 spin_unlock_irqrestore(&gpio_lock, flags); 309 return desc; 310 } 311 } 312 } 313 314 spin_unlock_irqrestore(&gpio_lock, flags); 315 316 return NULL; 317 } 318 319 /* 320 * Takes the names from gc->names and checks if they are all unique. If they 321 * are, they are assigned to their gpio descriptors. 322 * 323 * Warning if one of the names is already used for a different GPIO. 324 */ 325 static int gpiochip_set_desc_names(struct gpio_chip *gc) 326 { 327 struct gpio_device *gdev = gc->gpiodev; 328 int i; 329 330 if (!gc->names) 331 return 0; 332 333 /* First check all names if they are unique */ 334 for (i = 0; i != gc->ngpio; ++i) { 335 struct gpio_desc *gpio; 336 337 gpio = gpio_name_to_desc(gc->names[i]); 338 if (gpio) 339 dev_warn(&gdev->dev, 340 "Detected name collision for GPIO name '%s'\n", 341 gc->names[i]); 342 } 343 344 /* Then add all names to the GPIO descriptors */ 345 for (i = 0; i != gc->ngpio; ++i) 346 gdev->descs[i].name = gc->names[i]; 347 348 return 0; 349 } 350 351 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *chip) 352 { 353 unsigned long *p; 354 355 p = bitmap_alloc(chip->ngpio, GFP_KERNEL); 356 if (!p) 357 return NULL; 358 359 /* Assume by default all GPIOs are valid */ 360 bitmap_fill(p, chip->ngpio); 361 362 return p; 363 } 364 365 static int gpiochip_alloc_valid_mask(struct gpio_chip *gc) 366 { 367 if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask)) 368 return 0; 369 370 gc->valid_mask = gpiochip_allocate_mask(gc); 371 if (!gc->valid_mask) 372 return -ENOMEM; 373 374 return 0; 375 } 376 377 static int gpiochip_init_valid_mask(struct gpio_chip *gc) 378 { 379 if (gc->init_valid_mask) 380 return gc->init_valid_mask(gc, 381 gc->valid_mask, 382 gc->ngpio); 383 384 return 0; 385 } 386 387 static void gpiochip_free_valid_mask(struct gpio_chip *gpiochip) 388 { 389 bitmap_free(gpiochip->valid_mask); 390 gpiochip->valid_mask = NULL; 391 } 392 393 bool gpiochip_line_is_valid(const struct gpio_chip *gpiochip, 394 unsigned int offset) 395 { 396 /* No mask means all valid */ 397 if (likely(!gpiochip->valid_mask)) 398 return true; 399 return test_bit(offset, gpiochip->valid_mask); 400 } 401 EXPORT_SYMBOL_GPL(gpiochip_line_is_valid); 402 403 /* 404 * GPIO line handle management 405 */ 406 407 /** 408 * struct linehandle_state - contains the state of a userspace handle 409 * @gdev: the GPIO device the handle pertains to 410 * @label: consumer label used to tag descriptors 411 * @descs: the GPIO descriptors held by this handle 412 * @numdescs: the number of descriptors held in the descs array 413 */ 414 struct linehandle_state { 415 struct gpio_device *gdev; 416 const char *label; 417 struct gpio_desc *descs[GPIOHANDLES_MAX]; 418 u32 numdescs; 419 }; 420 421 #define GPIOHANDLE_REQUEST_VALID_FLAGS \ 422 (GPIOHANDLE_REQUEST_INPUT | \ 423 GPIOHANDLE_REQUEST_OUTPUT | \ 424 GPIOHANDLE_REQUEST_ACTIVE_LOW | \ 425 GPIOHANDLE_REQUEST_OPEN_DRAIN | \ 426 GPIOHANDLE_REQUEST_OPEN_SOURCE) 427 428 static long linehandle_ioctl(struct file *filep, unsigned int cmd, 429 unsigned long arg) 430 { 431 struct linehandle_state *lh = filep->private_data; 432 void __user *ip = (void __user *)arg; 433 struct gpiohandle_data ghd; 434 DECLARE_BITMAP(vals, GPIOHANDLES_MAX); 435 int i; 436 437 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) { 438 /* NOTE: It's ok to read values of output lines. */ 439 int ret = gpiod_get_array_value_complex(false, 440 true, 441 lh->numdescs, 442 lh->descs, 443 NULL, 444 vals); 445 if (ret) 446 return ret; 447 448 memset(&ghd, 0, sizeof(ghd)); 449 for (i = 0; i < lh->numdescs; i++) 450 ghd.values[i] = test_bit(i, vals); 451 452 if (copy_to_user(ip, &ghd, sizeof(ghd))) 453 return -EFAULT; 454 455 return 0; 456 } else if (cmd == GPIOHANDLE_SET_LINE_VALUES_IOCTL) { 457 /* 458 * All line descriptors were created at once with the same 459 * flags so just check if the first one is really output. 460 */ 461 if (!test_bit(FLAG_IS_OUT, &lh->descs[0]->flags)) 462 return -EPERM; 463 464 if (copy_from_user(&ghd, ip, sizeof(ghd))) 465 return -EFAULT; 466 467 /* Clamp all values to [0,1] */ 468 for (i = 0; i < lh->numdescs; i++) 469 __assign_bit(i, vals, ghd.values[i]); 470 471 /* Reuse the array setting function */ 472 return gpiod_set_array_value_complex(false, 473 true, 474 lh->numdescs, 475 lh->descs, 476 NULL, 477 vals); 478 } 479 return -EINVAL; 480 } 481 482 #ifdef CONFIG_COMPAT 483 static long linehandle_ioctl_compat(struct file *filep, unsigned int cmd, 484 unsigned long arg) 485 { 486 return linehandle_ioctl(filep, cmd, (unsigned long)compat_ptr(arg)); 487 } 488 #endif 489 490 static int linehandle_release(struct inode *inode, struct file *filep) 491 { 492 struct linehandle_state *lh = filep->private_data; 493 struct gpio_device *gdev = lh->gdev; 494 int i; 495 496 for (i = 0; i < lh->numdescs; i++) 497 gpiod_free(lh->descs[i]); 498 kfree(lh->label); 499 kfree(lh); 500 put_device(&gdev->dev); 501 return 0; 502 } 503 504 static const struct file_operations linehandle_fileops = { 505 .release = linehandle_release, 506 .owner = THIS_MODULE, 507 .llseek = noop_llseek, 508 .unlocked_ioctl = linehandle_ioctl, 509 #ifdef CONFIG_COMPAT 510 .compat_ioctl = linehandle_ioctl_compat, 511 #endif 512 }; 513 514 static int linehandle_create(struct gpio_device *gdev, void __user *ip) 515 { 516 struct gpiohandle_request handlereq; 517 struct linehandle_state *lh; 518 struct file *file; 519 int fd, i, count = 0, ret; 520 u32 lflags; 521 522 if (copy_from_user(&handlereq, ip, sizeof(handlereq))) 523 return -EFAULT; 524 if ((handlereq.lines == 0) || (handlereq.lines > GPIOHANDLES_MAX)) 525 return -EINVAL; 526 527 lflags = handlereq.flags; 528 529 /* Return an error if an unknown flag is set */ 530 if (lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) 531 return -EINVAL; 532 533 /* 534 * Do not allow both INPUT & OUTPUT flags to be set as they are 535 * contradictory. 536 */ 537 if ((lflags & GPIOHANDLE_REQUEST_INPUT) && 538 (lflags & GPIOHANDLE_REQUEST_OUTPUT)) 539 return -EINVAL; 540 541 /* 542 * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If 543 * the hardware actually supports enabling both at the same time the 544 * electrical result would be disastrous. 545 */ 546 if ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) && 547 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)) 548 return -EINVAL; 549 550 /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */ 551 if (!(lflags & GPIOHANDLE_REQUEST_OUTPUT) && 552 ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) || 553 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE))) 554 return -EINVAL; 555 556 lh = kzalloc(sizeof(*lh), GFP_KERNEL); 557 if (!lh) 558 return -ENOMEM; 559 lh->gdev = gdev; 560 get_device(&gdev->dev); 561 562 /* Make sure this is terminated */ 563 handlereq.consumer_label[sizeof(handlereq.consumer_label)-1] = '\0'; 564 if (strlen(handlereq.consumer_label)) { 565 lh->label = kstrdup(handlereq.consumer_label, 566 GFP_KERNEL); 567 if (!lh->label) { 568 ret = -ENOMEM; 569 goto out_free_lh; 570 } 571 } 572 573 /* Request each GPIO */ 574 for (i = 0; i < handlereq.lines; i++) { 575 u32 offset = handlereq.lineoffsets[i]; 576 struct gpio_desc *desc; 577 578 if (offset >= gdev->ngpio) { 579 ret = -EINVAL; 580 goto out_free_descs; 581 } 582 583 desc = &gdev->descs[offset]; 584 ret = gpiod_request(desc, lh->label); 585 if (ret) 586 goto out_free_descs; 587 lh->descs[i] = desc; 588 count = i + 1; 589 590 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW) 591 set_bit(FLAG_ACTIVE_LOW, &desc->flags); 592 if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) 593 set_bit(FLAG_OPEN_DRAIN, &desc->flags); 594 if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE) 595 set_bit(FLAG_OPEN_SOURCE, &desc->flags); 596 597 ret = gpiod_set_transitory(desc, false); 598 if (ret < 0) 599 goto out_free_descs; 600 601 /* 602 * Lines have to be requested explicitly for input 603 * or output, else the line will be treated "as is". 604 */ 605 if (lflags & GPIOHANDLE_REQUEST_OUTPUT) { 606 int val = !!handlereq.default_values[i]; 607 608 ret = gpiod_direction_output(desc, val); 609 if (ret) 610 goto out_free_descs; 611 } else if (lflags & GPIOHANDLE_REQUEST_INPUT) { 612 ret = gpiod_direction_input(desc); 613 if (ret) 614 goto out_free_descs; 615 } 616 dev_dbg(&gdev->dev, "registered chardev handle for line %d\n", 617 offset); 618 } 619 /* Let i point at the last handle */ 620 i--; 621 lh->numdescs = handlereq.lines; 622 623 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC); 624 if (fd < 0) { 625 ret = fd; 626 goto out_free_descs; 627 } 628 629 file = anon_inode_getfile("gpio-linehandle", 630 &linehandle_fileops, 631 lh, 632 O_RDONLY | O_CLOEXEC); 633 if (IS_ERR(file)) { 634 ret = PTR_ERR(file); 635 goto out_put_unused_fd; 636 } 637 638 handlereq.fd = fd; 639 if (copy_to_user(ip, &handlereq, sizeof(handlereq))) { 640 /* 641 * fput() will trigger the release() callback, so do not go onto 642 * the regular error cleanup path here. 643 */ 644 fput(file); 645 put_unused_fd(fd); 646 return -EFAULT; 647 } 648 649 fd_install(fd, file); 650 651 dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n", 652 lh->numdescs); 653 654 return 0; 655 656 out_put_unused_fd: 657 put_unused_fd(fd); 658 out_free_descs: 659 for (i = 0; i < count; i++) 660 gpiod_free(lh->descs[i]); 661 kfree(lh->label); 662 out_free_lh: 663 kfree(lh); 664 put_device(&gdev->dev); 665 return ret; 666 } 667 668 /* 669 * GPIO line event management 670 */ 671 672 /** 673 * struct lineevent_state - contains the state of a userspace event 674 * @gdev: the GPIO device the event pertains to 675 * @label: consumer label used to tag descriptors 676 * @desc: the GPIO descriptor held by this event 677 * @eflags: the event flags this line was requested with 678 * @irq: the interrupt that trigger in response to events on this GPIO 679 * @wait: wait queue that handles blocking reads of events 680 * @events: KFIFO for the GPIO events 681 * @read_lock: mutex lock to protect reads from colliding with adding 682 * new events to the FIFO 683 * @timestamp: cache for the timestamp storing it between hardirq 684 * and IRQ thread, used to bring the timestamp close to the actual 685 * event 686 */ 687 struct lineevent_state { 688 struct gpio_device *gdev; 689 const char *label; 690 struct gpio_desc *desc; 691 u32 eflags; 692 int irq; 693 wait_queue_head_t wait; 694 DECLARE_KFIFO(events, struct gpioevent_data, 16); 695 struct mutex read_lock; 696 u64 timestamp; 697 }; 698 699 #define GPIOEVENT_REQUEST_VALID_FLAGS \ 700 (GPIOEVENT_REQUEST_RISING_EDGE | \ 701 GPIOEVENT_REQUEST_FALLING_EDGE) 702 703 static __poll_t lineevent_poll(struct file *filep, 704 struct poll_table_struct *wait) 705 { 706 struct lineevent_state *le = filep->private_data; 707 __poll_t events = 0; 708 709 poll_wait(filep, &le->wait, wait); 710 711 if (!kfifo_is_empty(&le->events)) 712 events = EPOLLIN | EPOLLRDNORM; 713 714 return events; 715 } 716 717 718 static ssize_t lineevent_read(struct file *filep, 719 char __user *buf, 720 size_t count, 721 loff_t *f_ps) 722 { 723 struct lineevent_state *le = filep->private_data; 724 unsigned int copied; 725 int ret; 726 727 if (count < sizeof(struct gpioevent_data)) 728 return -EINVAL; 729 730 do { 731 if (kfifo_is_empty(&le->events)) { 732 if (filep->f_flags & O_NONBLOCK) 733 return -EAGAIN; 734 735 ret = wait_event_interruptible(le->wait, 736 !kfifo_is_empty(&le->events)); 737 if (ret) 738 return ret; 739 } 740 741 if (mutex_lock_interruptible(&le->read_lock)) 742 return -ERESTARTSYS; 743 ret = kfifo_to_user(&le->events, buf, count, &copied); 744 mutex_unlock(&le->read_lock); 745 746 if (ret) 747 return ret; 748 749 /* 750 * If we couldn't read anything from the fifo (a different 751 * thread might have been faster) we either return -EAGAIN if 752 * the file descriptor is non-blocking, otherwise we go back to 753 * sleep and wait for more data to arrive. 754 */ 755 if (copied == 0 && (filep->f_flags & O_NONBLOCK)) 756 return -EAGAIN; 757 758 } while (copied == 0); 759 760 return copied; 761 } 762 763 static int lineevent_release(struct inode *inode, struct file *filep) 764 { 765 struct lineevent_state *le = filep->private_data; 766 struct gpio_device *gdev = le->gdev; 767 768 free_irq(le->irq, le); 769 gpiod_free(le->desc); 770 kfree(le->label); 771 kfree(le); 772 put_device(&gdev->dev); 773 return 0; 774 } 775 776 static long lineevent_ioctl(struct file *filep, unsigned int cmd, 777 unsigned long arg) 778 { 779 struct lineevent_state *le = filep->private_data; 780 void __user *ip = (void __user *)arg; 781 struct gpiohandle_data ghd; 782 783 /* 784 * We can get the value for an event line but not set it, 785 * because it is input by definition. 786 */ 787 if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) { 788 int val; 789 790 memset(&ghd, 0, sizeof(ghd)); 791 792 val = gpiod_get_value_cansleep(le->desc); 793 if (val < 0) 794 return val; 795 ghd.values[0] = val; 796 797 if (copy_to_user(ip, &ghd, sizeof(ghd))) 798 return -EFAULT; 799 800 return 0; 801 } 802 return -EINVAL; 803 } 804 805 #ifdef CONFIG_COMPAT 806 static long lineevent_ioctl_compat(struct file *filep, unsigned int cmd, 807 unsigned long arg) 808 { 809 return lineevent_ioctl(filep, cmd, (unsigned long)compat_ptr(arg)); 810 } 811 #endif 812 813 static const struct file_operations lineevent_fileops = { 814 .release = lineevent_release, 815 .read = lineevent_read, 816 .poll = lineevent_poll, 817 .owner = THIS_MODULE, 818 .llseek = noop_llseek, 819 .unlocked_ioctl = lineevent_ioctl, 820 #ifdef CONFIG_COMPAT 821 .compat_ioctl = lineevent_ioctl_compat, 822 #endif 823 }; 824 825 static irqreturn_t lineevent_irq_thread(int irq, void *p) 826 { 827 struct lineevent_state *le = p; 828 struct gpioevent_data ge; 829 int ret; 830 831 /* Do not leak kernel stack to userspace */ 832 memset(&ge, 0, sizeof(ge)); 833 834 /* 835 * We may be running from a nested threaded interrupt in which case 836 * we didn't get the timestamp from lineevent_irq_handler(). 837 */ 838 if (!le->timestamp) 839 ge.timestamp = ktime_get_real_ns(); 840 else 841 ge.timestamp = le->timestamp; 842 843 if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE 844 && le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) { 845 int level = gpiod_get_value_cansleep(le->desc); 846 if (level) 847 /* Emit low-to-high event */ 848 ge.id = GPIOEVENT_EVENT_RISING_EDGE; 849 else 850 /* Emit high-to-low event */ 851 ge.id = GPIOEVENT_EVENT_FALLING_EDGE; 852 } else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE) { 853 /* Emit low-to-high event */ 854 ge.id = GPIOEVENT_EVENT_RISING_EDGE; 855 } else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) { 856 /* Emit high-to-low event */ 857 ge.id = GPIOEVENT_EVENT_FALLING_EDGE; 858 } else { 859 return IRQ_NONE; 860 } 861 862 ret = kfifo_put(&le->events, ge); 863 if (ret) 864 wake_up_poll(&le->wait, EPOLLIN); 865 866 return IRQ_HANDLED; 867 } 868 869 static irqreturn_t lineevent_irq_handler(int irq, void *p) 870 { 871 struct lineevent_state *le = p; 872 873 /* 874 * Just store the timestamp in hardirq context so we get it as 875 * close in time as possible to the actual event. 876 */ 877 le->timestamp = ktime_get_real_ns(); 878 879 return IRQ_WAKE_THREAD; 880 } 881 882 static int lineevent_create(struct gpio_device *gdev, void __user *ip) 883 { 884 struct gpioevent_request eventreq; 885 struct lineevent_state *le; 886 struct gpio_desc *desc; 887 struct file *file; 888 u32 offset; 889 u32 lflags; 890 u32 eflags; 891 int fd; 892 int ret; 893 int irqflags = 0; 894 895 if (copy_from_user(&eventreq, ip, sizeof(eventreq))) 896 return -EFAULT; 897 898 le = kzalloc(sizeof(*le), GFP_KERNEL); 899 if (!le) 900 return -ENOMEM; 901 le->gdev = gdev; 902 get_device(&gdev->dev); 903 904 /* Make sure this is terminated */ 905 eventreq.consumer_label[sizeof(eventreq.consumer_label)-1] = '\0'; 906 if (strlen(eventreq.consumer_label)) { 907 le->label = kstrdup(eventreq.consumer_label, 908 GFP_KERNEL); 909 if (!le->label) { 910 ret = -ENOMEM; 911 goto out_free_le; 912 } 913 } 914 915 offset = eventreq.lineoffset; 916 lflags = eventreq.handleflags; 917 eflags = eventreq.eventflags; 918 919 if (offset >= gdev->ngpio) { 920 ret = -EINVAL; 921 goto out_free_label; 922 } 923 924 /* Return an error if a unknown flag is set */ 925 if ((lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) || 926 (eflags & ~GPIOEVENT_REQUEST_VALID_FLAGS)) { 927 ret = -EINVAL; 928 goto out_free_label; 929 } 930 931 /* This is just wrong: we don't look for events on output lines */ 932 if ((lflags & GPIOHANDLE_REQUEST_OUTPUT) || 933 (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) || 934 (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)) { 935 ret = -EINVAL; 936 goto out_free_label; 937 } 938 939 desc = &gdev->descs[offset]; 940 ret = gpiod_request(desc, le->label); 941 if (ret) 942 goto out_free_label; 943 le->desc = desc; 944 le->eflags = eflags; 945 946 if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW) 947 set_bit(FLAG_ACTIVE_LOW, &desc->flags); 948 949 ret = gpiod_direction_input(desc); 950 if (ret) 951 goto out_free_desc; 952 953 le->irq = gpiod_to_irq(desc); 954 if (le->irq <= 0) { 955 ret = -ENODEV; 956 goto out_free_desc; 957 } 958 959 if (eflags & GPIOEVENT_REQUEST_RISING_EDGE) 960 irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ? 961 IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING; 962 if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE) 963 irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ? 964 IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING; 965 irqflags |= IRQF_ONESHOT; 966 967 INIT_KFIFO(le->events); 968 init_waitqueue_head(&le->wait); 969 mutex_init(&le->read_lock); 970 971 /* Request a thread to read the events */ 972 ret = request_threaded_irq(le->irq, 973 lineevent_irq_handler, 974 lineevent_irq_thread, 975 irqflags, 976 le->label, 977 le); 978 if (ret) 979 goto out_free_desc; 980 981 fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC); 982 if (fd < 0) { 983 ret = fd; 984 goto out_free_irq; 985 } 986 987 file = anon_inode_getfile("gpio-event", 988 &lineevent_fileops, 989 le, 990 O_RDONLY | O_CLOEXEC); 991 if (IS_ERR(file)) { 992 ret = PTR_ERR(file); 993 goto out_put_unused_fd; 994 } 995 996 eventreq.fd = fd; 997 if (copy_to_user(ip, &eventreq, sizeof(eventreq))) { 998 /* 999 * fput() will trigger the release() callback, so do not go onto 1000 * the regular error cleanup path here. 1001 */ 1002 fput(file); 1003 put_unused_fd(fd); 1004 return -EFAULT; 1005 } 1006 1007 fd_install(fd, file); 1008 1009 return 0; 1010 1011 out_put_unused_fd: 1012 put_unused_fd(fd); 1013 out_free_irq: 1014 free_irq(le->irq, le); 1015 out_free_desc: 1016 gpiod_free(le->desc); 1017 out_free_label: 1018 kfree(le->label); 1019 out_free_le: 1020 kfree(le); 1021 put_device(&gdev->dev); 1022 return ret; 1023 } 1024 1025 /* 1026 * gpio_ioctl() - ioctl handler for the GPIO chardev 1027 */ 1028 static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 1029 { 1030 struct gpio_device *gdev = filp->private_data; 1031 struct gpio_chip *chip = gdev->chip; 1032 void __user *ip = (void __user *)arg; 1033 1034 /* We fail any subsequent ioctl():s when the chip is gone */ 1035 if (!chip) 1036 return -ENODEV; 1037 1038 /* Fill in the struct and pass to userspace */ 1039 if (cmd == GPIO_GET_CHIPINFO_IOCTL) { 1040 struct gpiochip_info chipinfo; 1041 1042 memset(&chipinfo, 0, sizeof(chipinfo)); 1043 1044 strncpy(chipinfo.name, dev_name(&gdev->dev), 1045 sizeof(chipinfo.name)); 1046 chipinfo.name[sizeof(chipinfo.name)-1] = '\0'; 1047 strncpy(chipinfo.label, gdev->label, 1048 sizeof(chipinfo.label)); 1049 chipinfo.label[sizeof(chipinfo.label)-1] = '\0'; 1050 chipinfo.lines = gdev->ngpio; 1051 if (copy_to_user(ip, &chipinfo, sizeof(chipinfo))) 1052 return -EFAULT; 1053 return 0; 1054 } else if (cmd == GPIO_GET_LINEINFO_IOCTL) { 1055 struct gpioline_info lineinfo; 1056 struct gpio_desc *desc; 1057 1058 if (copy_from_user(&lineinfo, ip, sizeof(lineinfo))) 1059 return -EFAULT; 1060 if (lineinfo.line_offset >= gdev->ngpio) 1061 return -EINVAL; 1062 1063 desc = &gdev->descs[lineinfo.line_offset]; 1064 if (desc->name) { 1065 strncpy(lineinfo.name, desc->name, 1066 sizeof(lineinfo.name)); 1067 lineinfo.name[sizeof(lineinfo.name)-1] = '\0'; 1068 } else { 1069 lineinfo.name[0] = '\0'; 1070 } 1071 if (desc->label) { 1072 strncpy(lineinfo.consumer, desc->label, 1073 sizeof(lineinfo.consumer)); 1074 lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0'; 1075 } else { 1076 lineinfo.consumer[0] = '\0'; 1077 } 1078 1079 /* 1080 * Userspace only need to know that the kernel is using 1081 * this GPIO so it can't use it. 1082 */ 1083 lineinfo.flags = 0; 1084 if (test_bit(FLAG_REQUESTED, &desc->flags) || 1085 test_bit(FLAG_IS_HOGGED, &desc->flags) || 1086 test_bit(FLAG_USED_AS_IRQ, &desc->flags) || 1087 test_bit(FLAG_EXPORT, &desc->flags) || 1088 test_bit(FLAG_SYSFS, &desc->flags) || 1089 !pinctrl_gpio_can_use_line(chip->base + lineinfo.line_offset)) 1090 lineinfo.flags |= GPIOLINE_FLAG_KERNEL; 1091 if (test_bit(FLAG_IS_OUT, &desc->flags)) 1092 lineinfo.flags |= GPIOLINE_FLAG_IS_OUT; 1093 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) 1094 lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW; 1095 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) 1096 lineinfo.flags |= (GPIOLINE_FLAG_OPEN_DRAIN | 1097 GPIOLINE_FLAG_IS_OUT); 1098 if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) 1099 lineinfo.flags |= (GPIOLINE_FLAG_OPEN_SOURCE | 1100 GPIOLINE_FLAG_IS_OUT); 1101 1102 if (copy_to_user(ip, &lineinfo, sizeof(lineinfo))) 1103 return -EFAULT; 1104 return 0; 1105 } else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) { 1106 return linehandle_create(gdev, ip); 1107 } else if (cmd == GPIO_GET_LINEEVENT_IOCTL) { 1108 return lineevent_create(gdev, ip); 1109 } 1110 return -EINVAL; 1111 } 1112 1113 #ifdef CONFIG_COMPAT 1114 static long gpio_ioctl_compat(struct file *filp, unsigned int cmd, 1115 unsigned long arg) 1116 { 1117 return gpio_ioctl(filp, cmd, (unsigned long)compat_ptr(arg)); 1118 } 1119 #endif 1120 1121 /** 1122 * gpio_chrdev_open() - open the chardev for ioctl operations 1123 * @inode: inode for this chardev 1124 * @filp: file struct for storing private data 1125 * Returns 0 on success 1126 */ 1127 static int gpio_chrdev_open(struct inode *inode, struct file *filp) 1128 { 1129 struct gpio_device *gdev = container_of(inode->i_cdev, 1130 struct gpio_device, chrdev); 1131 1132 /* Fail on open if the backing gpiochip is gone */ 1133 if (!gdev->chip) 1134 return -ENODEV; 1135 get_device(&gdev->dev); 1136 filp->private_data = gdev; 1137 1138 return nonseekable_open(inode, filp); 1139 } 1140 1141 /** 1142 * gpio_chrdev_release() - close chardev after ioctl operations 1143 * @inode: inode for this chardev 1144 * @filp: file struct for storing private data 1145 * Returns 0 on success 1146 */ 1147 static int gpio_chrdev_release(struct inode *inode, struct file *filp) 1148 { 1149 struct gpio_device *gdev = container_of(inode->i_cdev, 1150 struct gpio_device, chrdev); 1151 1152 put_device(&gdev->dev); 1153 return 0; 1154 } 1155 1156 1157 static const struct file_operations gpio_fileops = { 1158 .release = gpio_chrdev_release, 1159 .open = gpio_chrdev_open, 1160 .owner = THIS_MODULE, 1161 .llseek = no_llseek, 1162 .unlocked_ioctl = gpio_ioctl, 1163 #ifdef CONFIG_COMPAT 1164 .compat_ioctl = gpio_ioctl_compat, 1165 #endif 1166 }; 1167 1168 static void gpiodevice_release(struct device *dev) 1169 { 1170 struct gpio_device *gdev = dev_get_drvdata(dev); 1171 1172 list_del(&gdev->list); 1173 ida_simple_remove(&gpio_ida, gdev->id); 1174 kfree_const(gdev->label); 1175 kfree(gdev->descs); 1176 kfree(gdev); 1177 } 1178 1179 static int gpiochip_setup_dev(struct gpio_device *gdev) 1180 { 1181 int ret; 1182 1183 cdev_init(&gdev->chrdev, &gpio_fileops); 1184 gdev->chrdev.owner = THIS_MODULE; 1185 gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id); 1186 1187 ret = cdev_device_add(&gdev->chrdev, &gdev->dev); 1188 if (ret) 1189 return ret; 1190 1191 chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n", 1192 MAJOR(gpio_devt), gdev->id); 1193 1194 ret = gpiochip_sysfs_register(gdev); 1195 if (ret) 1196 goto err_remove_device; 1197 1198 /* From this point, the .release() function cleans up gpio_device */ 1199 gdev->dev.release = gpiodevice_release; 1200 pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n", 1201 __func__, gdev->base, gdev->base + gdev->ngpio - 1, 1202 dev_name(&gdev->dev), gdev->chip->label ? : "generic"); 1203 1204 return 0; 1205 1206 err_remove_device: 1207 cdev_device_del(&gdev->chrdev, &gdev->dev); 1208 return ret; 1209 } 1210 1211 static void gpiochip_machine_hog(struct gpio_chip *chip, struct gpiod_hog *hog) 1212 { 1213 struct gpio_desc *desc; 1214 int rv; 1215 1216 desc = gpiochip_get_desc(chip, hog->chip_hwnum); 1217 if (IS_ERR(desc)) { 1218 pr_err("%s: unable to get GPIO desc: %ld\n", 1219 __func__, PTR_ERR(desc)); 1220 return; 1221 } 1222 1223 if (test_bit(FLAG_IS_HOGGED, &desc->flags)) 1224 return; 1225 1226 rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags); 1227 if (rv) 1228 pr_err("%s: unable to hog GPIO line (%s:%u): %d\n", 1229 __func__, chip->label, hog->chip_hwnum, rv); 1230 } 1231 1232 static void machine_gpiochip_add(struct gpio_chip *chip) 1233 { 1234 struct gpiod_hog *hog; 1235 1236 mutex_lock(&gpio_machine_hogs_mutex); 1237 1238 list_for_each_entry(hog, &gpio_machine_hogs, list) { 1239 if (!strcmp(chip->label, hog->chip_label)) 1240 gpiochip_machine_hog(chip, hog); 1241 } 1242 1243 mutex_unlock(&gpio_machine_hogs_mutex); 1244 } 1245 1246 static void gpiochip_setup_devs(void) 1247 { 1248 struct gpio_device *gdev; 1249 int ret; 1250 1251 list_for_each_entry(gdev, &gpio_devices, list) { 1252 ret = gpiochip_setup_dev(gdev); 1253 if (ret) 1254 pr_err("%s: Failed to initialize gpio device (%d)\n", 1255 dev_name(&gdev->dev), ret); 1256 } 1257 } 1258 1259 int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data, 1260 struct lock_class_key *lock_key, 1261 struct lock_class_key *request_key) 1262 { 1263 unsigned long flags; 1264 int ret = 0; 1265 unsigned i; 1266 int base = chip->base; 1267 struct gpio_device *gdev; 1268 1269 /* 1270 * First: allocate and populate the internal stat container, and 1271 * set up the struct device. 1272 */ 1273 gdev = kzalloc(sizeof(*gdev), GFP_KERNEL); 1274 if (!gdev) 1275 return -ENOMEM; 1276 gdev->dev.bus = &gpio_bus_type; 1277 gdev->chip = chip; 1278 chip->gpiodev = gdev; 1279 if (chip->parent) { 1280 gdev->dev.parent = chip->parent; 1281 gdev->dev.of_node = chip->parent->of_node; 1282 } 1283 1284 #ifdef CONFIG_OF_GPIO 1285 /* If the gpiochip has an assigned OF node this takes precedence */ 1286 if (chip->of_node) 1287 gdev->dev.of_node = chip->of_node; 1288 else 1289 chip->of_node = gdev->dev.of_node; 1290 #endif 1291 1292 gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL); 1293 if (gdev->id < 0) { 1294 ret = gdev->id; 1295 goto err_free_gdev; 1296 } 1297 dev_set_name(&gdev->dev, "gpiochip%d", gdev->id); 1298 device_initialize(&gdev->dev); 1299 dev_set_drvdata(&gdev->dev, gdev); 1300 if (chip->parent && chip->parent->driver) 1301 gdev->owner = chip->parent->driver->owner; 1302 else if (chip->owner) 1303 /* TODO: remove chip->owner */ 1304 gdev->owner = chip->owner; 1305 else 1306 gdev->owner = THIS_MODULE; 1307 1308 gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL); 1309 if (!gdev->descs) { 1310 ret = -ENOMEM; 1311 goto err_free_ida; 1312 } 1313 1314 if (chip->ngpio == 0) { 1315 chip_err(chip, "tried to insert a GPIO chip with zero lines\n"); 1316 ret = -EINVAL; 1317 goto err_free_descs; 1318 } 1319 1320 if (chip->ngpio > FASTPATH_NGPIO) 1321 chip_warn(chip, "line cnt %u is greater than fast path cnt %u\n", 1322 chip->ngpio, FASTPATH_NGPIO); 1323 1324 gdev->label = kstrdup_const(chip->label ?: "unknown", GFP_KERNEL); 1325 if (!gdev->label) { 1326 ret = -ENOMEM; 1327 goto err_free_descs; 1328 } 1329 1330 gdev->ngpio = chip->ngpio; 1331 gdev->data = data; 1332 1333 spin_lock_irqsave(&gpio_lock, flags); 1334 1335 /* 1336 * TODO: this allocates a Linux GPIO number base in the global 1337 * GPIO numberspace for this chip. In the long run we want to 1338 * get *rid* of this numberspace and use only descriptors, but 1339 * it may be a pipe dream. It will not happen before we get rid 1340 * of the sysfs interface anyways. 1341 */ 1342 if (base < 0) { 1343 base = gpiochip_find_base(chip->ngpio); 1344 if (base < 0) { 1345 ret = base; 1346 spin_unlock_irqrestore(&gpio_lock, flags); 1347 goto err_free_label; 1348 } 1349 /* 1350 * TODO: it should not be necessary to reflect the assigned 1351 * base outside of the GPIO subsystem. Go over drivers and 1352 * see if anyone makes use of this, else drop this and assign 1353 * a poison instead. 1354 */ 1355 chip->base = base; 1356 } 1357 gdev->base = base; 1358 1359 ret = gpiodev_add_to_list(gdev); 1360 if (ret) { 1361 spin_unlock_irqrestore(&gpio_lock, flags); 1362 goto err_free_label; 1363 } 1364 1365 spin_unlock_irqrestore(&gpio_lock, flags); 1366 1367 for (i = 0; i < chip->ngpio; i++) 1368 gdev->descs[i].gdev = gdev; 1369 1370 #ifdef CONFIG_PINCTRL 1371 INIT_LIST_HEAD(&gdev->pin_ranges); 1372 #endif 1373 1374 ret = gpiochip_set_desc_names(chip); 1375 if (ret) 1376 goto err_remove_from_list; 1377 1378 ret = gpiochip_alloc_valid_mask(chip); 1379 if (ret) 1380 goto err_remove_from_list; 1381 1382 ret = of_gpiochip_add(chip); 1383 if (ret) 1384 goto err_free_gpiochip_mask; 1385 1386 ret = gpiochip_init_valid_mask(chip); 1387 if (ret) 1388 goto err_remove_of_chip; 1389 1390 for (i = 0; i < chip->ngpio; i++) { 1391 struct gpio_desc *desc = &gdev->descs[i]; 1392 1393 if (chip->get_direction && gpiochip_line_is_valid(chip, i)) { 1394 if (!chip->get_direction(chip, i)) 1395 set_bit(FLAG_IS_OUT, &desc->flags); 1396 else 1397 clear_bit(FLAG_IS_OUT, &desc->flags); 1398 } else { 1399 if (!chip->direction_input) 1400 set_bit(FLAG_IS_OUT, &desc->flags); 1401 else 1402 clear_bit(FLAG_IS_OUT, &desc->flags); 1403 } 1404 } 1405 1406 acpi_gpiochip_add(chip); 1407 1408 machine_gpiochip_add(chip); 1409 1410 ret = gpiochip_irqchip_init_hw(chip); 1411 if (ret) 1412 goto err_remove_acpi_chip; 1413 1414 ret = gpiochip_irqchip_init_valid_mask(chip); 1415 if (ret) 1416 goto err_remove_acpi_chip; 1417 1418 ret = gpiochip_add_irqchip(chip, lock_key, request_key); 1419 if (ret) 1420 goto err_remove_irqchip_mask; 1421 1422 /* 1423 * By first adding the chardev, and then adding the device, 1424 * we get a device node entry in sysfs under 1425 * /sys/bus/gpio/devices/gpiochipN/dev that can be used for 1426 * coldplug of device nodes and other udev business. 1427 * We can do this only if gpiolib has been initialized. 1428 * Otherwise, defer until later. 1429 */ 1430 if (gpiolib_initialized) { 1431 ret = gpiochip_setup_dev(gdev); 1432 if (ret) 1433 goto err_remove_irqchip; 1434 } 1435 return 0; 1436 1437 err_remove_irqchip: 1438 gpiochip_irqchip_remove(chip); 1439 err_remove_irqchip_mask: 1440 gpiochip_irqchip_free_valid_mask(chip); 1441 err_remove_acpi_chip: 1442 acpi_gpiochip_remove(chip); 1443 err_remove_of_chip: 1444 gpiochip_free_hogs(chip); 1445 of_gpiochip_remove(chip); 1446 err_free_gpiochip_mask: 1447 gpiochip_free_valid_mask(chip); 1448 err_remove_from_list: 1449 spin_lock_irqsave(&gpio_lock, flags); 1450 list_del(&gdev->list); 1451 spin_unlock_irqrestore(&gpio_lock, flags); 1452 err_free_label: 1453 kfree_const(gdev->label); 1454 err_free_descs: 1455 kfree(gdev->descs); 1456 err_free_ida: 1457 ida_simple_remove(&gpio_ida, gdev->id); 1458 err_free_gdev: 1459 /* failures here can mean systems won't boot... */ 1460 pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__, 1461 gdev->base, gdev->base + gdev->ngpio - 1, 1462 chip->label ? : "generic", ret); 1463 kfree(gdev); 1464 return ret; 1465 } 1466 EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key); 1467 1468 /** 1469 * gpiochip_get_data() - get per-subdriver data for the chip 1470 * @chip: GPIO chip 1471 * 1472 * Returns: 1473 * The per-subdriver data for the chip. 1474 */ 1475 void *gpiochip_get_data(struct gpio_chip *chip) 1476 { 1477 return chip->gpiodev->data; 1478 } 1479 EXPORT_SYMBOL_GPL(gpiochip_get_data); 1480 1481 /** 1482 * gpiochip_remove() - unregister a gpio_chip 1483 * @chip: the chip to unregister 1484 * 1485 * A gpio_chip with any GPIOs still requested may not be removed. 1486 */ 1487 void gpiochip_remove(struct gpio_chip *chip) 1488 { 1489 struct gpio_device *gdev = chip->gpiodev; 1490 struct gpio_desc *desc; 1491 unsigned long flags; 1492 unsigned i; 1493 bool requested = false; 1494 1495 /* FIXME: should the legacy sysfs handling be moved to gpio_device? */ 1496 gpiochip_sysfs_unregister(gdev); 1497 gpiochip_free_hogs(chip); 1498 /* Numb the device, cancelling all outstanding operations */ 1499 gdev->chip = NULL; 1500 gpiochip_irqchip_remove(chip); 1501 acpi_gpiochip_remove(chip); 1502 gpiochip_remove_pin_ranges(chip); 1503 of_gpiochip_remove(chip); 1504 gpiochip_free_valid_mask(chip); 1505 /* 1506 * We accept no more calls into the driver from this point, so 1507 * NULL the driver data pointer 1508 */ 1509 gdev->data = NULL; 1510 1511 spin_lock_irqsave(&gpio_lock, flags); 1512 for (i = 0; i < gdev->ngpio; i++) { 1513 desc = &gdev->descs[i]; 1514 if (test_bit(FLAG_REQUESTED, &desc->flags)) 1515 requested = true; 1516 } 1517 spin_unlock_irqrestore(&gpio_lock, flags); 1518 1519 if (requested) 1520 dev_crit(&gdev->dev, 1521 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n"); 1522 1523 /* 1524 * The gpiochip side puts its use of the device to rest here: 1525 * if there are no userspace clients, the chardev and device will 1526 * be removed, else it will be dangling until the last user is 1527 * gone. 1528 */ 1529 cdev_device_del(&gdev->chrdev, &gdev->dev); 1530 put_device(&gdev->dev); 1531 } 1532 EXPORT_SYMBOL_GPL(gpiochip_remove); 1533 1534 static void devm_gpio_chip_release(struct device *dev, void *res) 1535 { 1536 struct gpio_chip *chip = *(struct gpio_chip **)res; 1537 1538 gpiochip_remove(chip); 1539 } 1540 1541 /** 1542 * devm_gpiochip_add_data() - Resource manager gpiochip_add_data() 1543 * @dev: pointer to the device that gpio_chip belongs to. 1544 * @chip: the chip to register, with chip->base initialized 1545 * @data: driver-private data associated with this chip 1546 * 1547 * Context: potentially before irqs will work 1548 * 1549 * The gpio chip automatically be released when the device is unbound. 1550 * 1551 * Returns: 1552 * A negative errno if the chip can't be registered, such as because the 1553 * chip->base is invalid or already associated with a different chip. 1554 * Otherwise it returns zero as a success code. 1555 */ 1556 int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip, 1557 void *data) 1558 { 1559 struct gpio_chip **ptr; 1560 int ret; 1561 1562 ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr), 1563 GFP_KERNEL); 1564 if (!ptr) 1565 return -ENOMEM; 1566 1567 ret = gpiochip_add_data(chip, data); 1568 if (ret < 0) { 1569 devres_free(ptr); 1570 return ret; 1571 } 1572 1573 *ptr = chip; 1574 devres_add(dev, ptr); 1575 1576 return 0; 1577 } 1578 EXPORT_SYMBOL_GPL(devm_gpiochip_add_data); 1579 1580 /** 1581 * gpiochip_find() - iterator for locating a specific gpio_chip 1582 * @data: data to pass to match function 1583 * @match: Callback function to check gpio_chip 1584 * 1585 * Similar to bus_find_device. It returns a reference to a gpio_chip as 1586 * determined by a user supplied @match callback. The callback should return 1587 * 0 if the device doesn't match and non-zero if it does. If the callback is 1588 * non-zero, this function will return to the caller and not iterate over any 1589 * more gpio_chips. 1590 */ 1591 struct gpio_chip *gpiochip_find(void *data, 1592 int (*match)(struct gpio_chip *chip, 1593 void *data)) 1594 { 1595 struct gpio_device *gdev; 1596 struct gpio_chip *chip = NULL; 1597 unsigned long flags; 1598 1599 spin_lock_irqsave(&gpio_lock, flags); 1600 list_for_each_entry(gdev, &gpio_devices, list) 1601 if (gdev->chip && match(gdev->chip, data)) { 1602 chip = gdev->chip; 1603 break; 1604 } 1605 1606 spin_unlock_irqrestore(&gpio_lock, flags); 1607 1608 return chip; 1609 } 1610 EXPORT_SYMBOL_GPL(gpiochip_find); 1611 1612 static int gpiochip_match_name(struct gpio_chip *chip, void *data) 1613 { 1614 const char *name = data; 1615 1616 return !strcmp(chip->label, name); 1617 } 1618 1619 static struct gpio_chip *find_chip_by_name(const char *name) 1620 { 1621 return gpiochip_find((void *)name, gpiochip_match_name); 1622 } 1623 1624 #ifdef CONFIG_GPIOLIB_IRQCHIP 1625 1626 /* 1627 * The following is irqchip helper code for gpiochips. 1628 */ 1629 1630 static int gpiochip_irqchip_init_hw(struct gpio_chip *gc) 1631 { 1632 struct gpio_irq_chip *girq = &gc->irq; 1633 1634 if (!girq->init_hw) 1635 return 0; 1636 1637 return girq->init_hw(gc); 1638 } 1639 1640 static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc) 1641 { 1642 struct gpio_irq_chip *girq = &gc->irq; 1643 1644 if (!girq->init_valid_mask) 1645 return 0; 1646 1647 girq->valid_mask = gpiochip_allocate_mask(gc); 1648 if (!girq->valid_mask) 1649 return -ENOMEM; 1650 1651 girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio); 1652 1653 return 0; 1654 } 1655 1656 static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip) 1657 { 1658 bitmap_free(gpiochip->irq.valid_mask); 1659 gpiochip->irq.valid_mask = NULL; 1660 } 1661 1662 bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip, 1663 unsigned int offset) 1664 { 1665 if (!gpiochip_line_is_valid(gpiochip, offset)) 1666 return false; 1667 /* No mask means all valid */ 1668 if (likely(!gpiochip->irq.valid_mask)) 1669 return true; 1670 return test_bit(offset, gpiochip->irq.valid_mask); 1671 } 1672 EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid); 1673 1674 /** 1675 * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip 1676 * @gc: the gpiochip to set the irqchip chain to 1677 * @parent_irq: the irq number corresponding to the parent IRQ for this 1678 * chained irqchip 1679 * @parent_handler: the parent interrupt handler for the accumulated IRQ 1680 * coming out of the gpiochip. If the interrupt is nested rather than 1681 * cascaded, pass NULL in this handler argument 1682 */ 1683 static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gc, 1684 unsigned int parent_irq, 1685 irq_flow_handler_t parent_handler) 1686 { 1687 struct gpio_irq_chip *girq = &gc->irq; 1688 struct device *dev = &gc->gpiodev->dev; 1689 1690 if (!girq->domain) { 1691 chip_err(gc, "called %s before setting up irqchip\n", 1692 __func__); 1693 return; 1694 } 1695 1696 if (parent_handler) { 1697 if (gc->can_sleep) { 1698 chip_err(gc, 1699 "you cannot have chained interrupts on a chip that may sleep\n"); 1700 return; 1701 } 1702 girq->parents = devm_kcalloc(dev, 1, 1703 sizeof(*girq->parents), 1704 GFP_KERNEL); 1705 if (!girq->parents) { 1706 chip_err(gc, "out of memory allocating parent IRQ\n"); 1707 return; 1708 } 1709 girq->parents[0] = parent_irq; 1710 girq->num_parents = 1; 1711 /* 1712 * The parent irqchip is already using the chip_data for this 1713 * irqchip, so our callbacks simply use the handler_data. 1714 */ 1715 irq_set_chained_handler_and_data(parent_irq, parent_handler, 1716 gc); 1717 } 1718 } 1719 1720 /** 1721 * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip 1722 * @gpiochip: the gpiochip to set the irqchip chain to 1723 * @irqchip: the irqchip to chain to the gpiochip 1724 * @parent_irq: the irq number corresponding to the parent IRQ for this 1725 * chained irqchip 1726 * @parent_handler: the parent interrupt handler for the accumulated IRQ 1727 * coming out of the gpiochip. 1728 */ 1729 void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip, 1730 struct irq_chip *irqchip, 1731 unsigned int parent_irq, 1732 irq_flow_handler_t parent_handler) 1733 { 1734 if (gpiochip->irq.threaded) { 1735 chip_err(gpiochip, "tried to chain a threaded gpiochip\n"); 1736 return; 1737 } 1738 1739 gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, parent_handler); 1740 } 1741 EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip); 1742 1743 /** 1744 * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip 1745 * @gpiochip: the gpiochip to set the irqchip nested handler to 1746 * @irqchip: the irqchip to nest to the gpiochip 1747 * @parent_irq: the irq number corresponding to the parent IRQ for this 1748 * nested irqchip 1749 */ 1750 void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip, 1751 struct irq_chip *irqchip, 1752 unsigned int parent_irq) 1753 { 1754 gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, NULL); 1755 } 1756 EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip); 1757 1758 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY 1759 1760 /** 1761 * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip 1762 * to a gpiochip 1763 * @gc: the gpiochip to set the irqchip hierarchical handler to 1764 * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt 1765 * will then percolate up to the parent 1766 */ 1767 static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc, 1768 struct irq_chip *irqchip) 1769 { 1770 /* DT will deal with mapping each IRQ as we go along */ 1771 if (is_of_node(gc->irq.fwnode)) 1772 return; 1773 1774 /* 1775 * This is for legacy and boardfile "irqchip" fwnodes: allocate 1776 * irqs upfront instead of dynamically since we don't have the 1777 * dynamic type of allocation that hardware description languages 1778 * provide. Once all GPIO drivers using board files are gone from 1779 * the kernel we can delete this code, but for a transitional period 1780 * it is necessary to keep this around. 1781 */ 1782 if (is_fwnode_irqchip(gc->irq.fwnode)) { 1783 int i; 1784 int ret; 1785 1786 for (i = 0; i < gc->ngpio; i++) { 1787 struct irq_fwspec fwspec; 1788 unsigned int parent_hwirq; 1789 unsigned int parent_type; 1790 struct gpio_irq_chip *girq = &gc->irq; 1791 1792 /* 1793 * We call the child to parent translation function 1794 * only to check if the child IRQ is valid or not. 1795 * Just pick the rising edge type here as that is what 1796 * we likely need to support. 1797 */ 1798 ret = girq->child_to_parent_hwirq(gc, i, 1799 IRQ_TYPE_EDGE_RISING, 1800 &parent_hwirq, 1801 &parent_type); 1802 if (ret) { 1803 chip_err(gc, "skip set-up on hwirq %d\n", 1804 i); 1805 continue; 1806 } 1807 1808 fwspec.fwnode = gc->irq.fwnode; 1809 /* This is the hwirq for the GPIO line side of things */ 1810 fwspec.param[0] = girq->child_offset_to_irq(gc, i); 1811 /* Just pick something */ 1812 fwspec.param[1] = IRQ_TYPE_EDGE_RISING; 1813 fwspec.param_count = 2; 1814 ret = __irq_domain_alloc_irqs(gc->irq.domain, 1815 /* just pick something */ 1816 -1, 1817 1, 1818 NUMA_NO_NODE, 1819 &fwspec, 1820 false, 1821 NULL); 1822 if (ret < 0) { 1823 chip_err(gc, 1824 "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n", 1825 i, parent_hwirq, 1826 ret); 1827 } 1828 } 1829 } 1830 1831 chip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__); 1832 1833 return; 1834 } 1835 1836 static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d, 1837 struct irq_fwspec *fwspec, 1838 unsigned long *hwirq, 1839 unsigned int *type) 1840 { 1841 /* We support standard DT translation */ 1842 if (is_of_node(fwspec->fwnode) && fwspec->param_count == 2) { 1843 return irq_domain_translate_twocell(d, fwspec, hwirq, type); 1844 } 1845 1846 /* This is for board files and others not using DT */ 1847 if (is_fwnode_irqchip(fwspec->fwnode)) { 1848 int ret; 1849 1850 ret = irq_domain_translate_twocell(d, fwspec, hwirq, type); 1851 if (ret) 1852 return ret; 1853 WARN_ON(*type == IRQ_TYPE_NONE); 1854 return 0; 1855 } 1856 return -EINVAL; 1857 } 1858 1859 static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d, 1860 unsigned int irq, 1861 unsigned int nr_irqs, 1862 void *data) 1863 { 1864 struct gpio_chip *gc = d->host_data; 1865 irq_hw_number_t hwirq; 1866 unsigned int type = IRQ_TYPE_NONE; 1867 struct irq_fwspec *fwspec = data; 1868 struct irq_fwspec parent_fwspec; 1869 unsigned int parent_hwirq; 1870 unsigned int parent_type; 1871 struct gpio_irq_chip *girq = &gc->irq; 1872 int ret; 1873 1874 /* 1875 * The nr_irqs parameter is always one except for PCI multi-MSI 1876 * so this should not happen. 1877 */ 1878 WARN_ON(nr_irqs != 1); 1879 1880 ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type); 1881 if (ret) 1882 return ret; 1883 1884 chip_info(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq); 1885 1886 ret = girq->child_to_parent_hwirq(gc, hwirq, type, 1887 &parent_hwirq, &parent_type); 1888 if (ret) { 1889 chip_err(gc, "can't look up hwirq %lu\n", hwirq); 1890 return ret; 1891 } 1892 chip_info(gc, "found parent hwirq %u\n", parent_hwirq); 1893 1894 /* 1895 * We set handle_bad_irq because the .set_type() should 1896 * always be invoked and set the right type of handler. 1897 */ 1898 irq_domain_set_info(d, 1899 irq, 1900 hwirq, 1901 gc->irq.chip, 1902 gc, 1903 girq->handler, 1904 NULL, NULL); 1905 irq_set_probe(irq); 1906 1907 /* 1908 * Create a IRQ fwspec to send up to the parent irqdomain: 1909 * specify the hwirq we address on the parent and tie it 1910 * all together up the chain. 1911 */ 1912 parent_fwspec.fwnode = d->parent->fwnode; 1913 /* This parent only handles asserted level IRQs */ 1914 girq->populate_parent_fwspec(gc, &parent_fwspec, parent_hwirq, 1915 parent_type); 1916 chip_info(gc, "alloc_irqs_parent for %d parent hwirq %d\n", 1917 irq, parent_hwirq); 1918 ret = irq_domain_alloc_irqs_parent(d, irq, 1, &parent_fwspec); 1919 if (ret) 1920 chip_err(gc, 1921 "failed to allocate parent hwirq %d for hwirq %lu\n", 1922 parent_hwirq, hwirq); 1923 1924 return ret; 1925 } 1926 1927 static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *chip, 1928 unsigned int offset) 1929 { 1930 return offset; 1931 } 1932 1933 static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops) 1934 { 1935 ops->activate = gpiochip_irq_domain_activate; 1936 ops->deactivate = gpiochip_irq_domain_deactivate; 1937 ops->alloc = gpiochip_hierarchy_irq_domain_alloc; 1938 ops->free = irq_domain_free_irqs_common; 1939 1940 /* 1941 * We only allow overriding the translate() function for 1942 * hierarchical chips, and this should only be done if the user 1943 * really need something other than 1:1 translation. 1944 */ 1945 if (!ops->translate) 1946 ops->translate = gpiochip_hierarchy_irq_domain_translate; 1947 } 1948 1949 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc) 1950 { 1951 if (!gc->irq.child_to_parent_hwirq || 1952 !gc->irq.fwnode) { 1953 chip_err(gc, "missing irqdomain vital data\n"); 1954 return -EINVAL; 1955 } 1956 1957 if (!gc->irq.child_offset_to_irq) 1958 gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop; 1959 1960 if (!gc->irq.populate_parent_fwspec) 1961 gc->irq.populate_parent_fwspec = 1962 gpiochip_populate_parent_fwspec_twocell; 1963 1964 gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops); 1965 1966 gc->irq.domain = irq_domain_create_hierarchy( 1967 gc->irq.parent_domain, 1968 0, 1969 gc->ngpio, 1970 gc->irq.fwnode, 1971 &gc->irq.child_irq_domain_ops, 1972 gc); 1973 1974 if (!gc->irq.domain) 1975 return -ENOMEM; 1976 1977 gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip); 1978 1979 return 0; 1980 } 1981 1982 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc) 1983 { 1984 return !!gc->irq.parent_domain; 1985 } 1986 1987 void gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *chip, 1988 struct irq_fwspec *fwspec, 1989 unsigned int parent_hwirq, 1990 unsigned int parent_type) 1991 { 1992 fwspec->param_count = 2; 1993 fwspec->param[0] = parent_hwirq; 1994 fwspec->param[1] = parent_type; 1995 } 1996 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell); 1997 1998 void gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *chip, 1999 struct irq_fwspec *fwspec, 2000 unsigned int parent_hwirq, 2001 unsigned int parent_type) 2002 { 2003 fwspec->param_count = 4; 2004 fwspec->param[0] = 0; 2005 fwspec->param[1] = parent_hwirq; 2006 fwspec->param[2] = 0; 2007 fwspec->param[3] = parent_type; 2008 } 2009 EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell); 2010 2011 #else 2012 2013 static int gpiochip_hierarchy_add_domain(struct gpio_chip *gc) 2014 { 2015 return -EINVAL; 2016 } 2017 2018 static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc) 2019 { 2020 return false; 2021 } 2022 2023 #endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */ 2024 2025 /** 2026 * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip 2027 * @d: the irqdomain used by this irqchip 2028 * @irq: the global irq number used by this GPIO irqchip irq 2029 * @hwirq: the local IRQ/GPIO line offset on this gpiochip 2030 * 2031 * This function will set up the mapping for a certain IRQ line on a 2032 * gpiochip by assigning the gpiochip as chip data, and using the irqchip 2033 * stored inside the gpiochip. 2034 */ 2035 int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, 2036 irq_hw_number_t hwirq) 2037 { 2038 struct gpio_chip *chip = d->host_data; 2039 int ret = 0; 2040 2041 if (!gpiochip_irqchip_irq_valid(chip, hwirq)) 2042 return -ENXIO; 2043 2044 irq_set_chip_data(irq, chip); 2045 /* 2046 * This lock class tells lockdep that GPIO irqs are in a different 2047 * category than their parents, so it won't report false recursion. 2048 */ 2049 irq_set_lockdep_class(irq, chip->irq.lock_key, chip->irq.request_key); 2050 irq_set_chip_and_handler(irq, chip->irq.chip, chip->irq.handler); 2051 /* Chips that use nested thread handlers have them marked */ 2052 if (chip->irq.threaded) 2053 irq_set_nested_thread(irq, 1); 2054 irq_set_noprobe(irq); 2055 2056 if (chip->irq.num_parents == 1) 2057 ret = irq_set_parent(irq, chip->irq.parents[0]); 2058 else if (chip->irq.map) 2059 ret = irq_set_parent(irq, chip->irq.map[hwirq]); 2060 2061 if (ret < 0) 2062 return ret; 2063 2064 /* 2065 * No set-up of the hardware will happen if IRQ_TYPE_NONE 2066 * is passed as default type. 2067 */ 2068 if (chip->irq.default_type != IRQ_TYPE_NONE) 2069 irq_set_irq_type(irq, chip->irq.default_type); 2070 2071 return 0; 2072 } 2073 EXPORT_SYMBOL_GPL(gpiochip_irq_map); 2074 2075 void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq) 2076 { 2077 struct gpio_chip *chip = d->host_data; 2078 2079 if (chip->irq.threaded) 2080 irq_set_nested_thread(irq, 0); 2081 irq_set_chip_and_handler(irq, NULL, NULL); 2082 irq_set_chip_data(irq, NULL); 2083 } 2084 EXPORT_SYMBOL_GPL(gpiochip_irq_unmap); 2085 2086 static const struct irq_domain_ops gpiochip_domain_ops = { 2087 .map = gpiochip_irq_map, 2088 .unmap = gpiochip_irq_unmap, 2089 /* Virtually all GPIO irqchips are twocell:ed */ 2090 .xlate = irq_domain_xlate_twocell, 2091 }; 2092 2093 /* 2094 * TODO: move these activate/deactivate in under the hierarchicial 2095 * irqchip implementation as static once SPMI and SSBI (all external 2096 * users) are phased over. 2097 */ 2098 /** 2099 * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ 2100 * @domain: The IRQ domain used by this IRQ chip 2101 * @data: Outermost irq_data associated with the IRQ 2102 * @reserve: If set, only reserve an interrupt vector instead of assigning one 2103 * 2104 * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be 2105 * used as the activate function for the &struct irq_domain_ops. The host_data 2106 * for the IRQ domain must be the &struct gpio_chip. 2107 */ 2108 int gpiochip_irq_domain_activate(struct irq_domain *domain, 2109 struct irq_data *data, bool reserve) 2110 { 2111 struct gpio_chip *chip = domain->host_data; 2112 2113 return gpiochip_lock_as_irq(chip, data->hwirq); 2114 } 2115 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_activate); 2116 2117 /** 2118 * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ 2119 * @domain: The IRQ domain used by this IRQ chip 2120 * @data: Outermost irq_data associated with the IRQ 2121 * 2122 * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to 2123 * be used as the deactivate function for the &struct irq_domain_ops. The 2124 * host_data for the IRQ domain must be the &struct gpio_chip. 2125 */ 2126 void gpiochip_irq_domain_deactivate(struct irq_domain *domain, 2127 struct irq_data *data) 2128 { 2129 struct gpio_chip *chip = domain->host_data; 2130 2131 return gpiochip_unlock_as_irq(chip, data->hwirq); 2132 } 2133 EXPORT_SYMBOL_GPL(gpiochip_irq_domain_deactivate); 2134 2135 static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset) 2136 { 2137 struct irq_domain *domain = chip->irq.domain; 2138 2139 if (!gpiochip_irqchip_irq_valid(chip, offset)) 2140 return -ENXIO; 2141 2142 #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY 2143 if (irq_domain_is_hierarchy(domain)) { 2144 struct irq_fwspec spec; 2145 2146 spec.fwnode = domain->fwnode; 2147 spec.param_count = 2; 2148 spec.param[0] = chip->irq.child_offset_to_irq(chip, offset); 2149 spec.param[1] = IRQ_TYPE_NONE; 2150 2151 return irq_create_fwspec_mapping(&spec); 2152 } 2153 #endif 2154 2155 return irq_create_mapping(domain, offset); 2156 } 2157 2158 static int gpiochip_irq_reqres(struct irq_data *d) 2159 { 2160 struct gpio_chip *chip = irq_data_get_irq_chip_data(d); 2161 2162 return gpiochip_reqres_irq(chip, d->hwirq); 2163 } 2164 2165 static void gpiochip_irq_relres(struct irq_data *d) 2166 { 2167 struct gpio_chip *chip = irq_data_get_irq_chip_data(d); 2168 2169 gpiochip_relres_irq(chip, d->hwirq); 2170 } 2171 2172 static void gpiochip_irq_enable(struct irq_data *d) 2173 { 2174 struct gpio_chip *chip = irq_data_get_irq_chip_data(d); 2175 2176 gpiochip_enable_irq(chip, d->hwirq); 2177 if (chip->irq.irq_enable) 2178 chip->irq.irq_enable(d); 2179 else 2180 chip->irq.chip->irq_unmask(d); 2181 } 2182 2183 static void gpiochip_irq_disable(struct irq_data *d) 2184 { 2185 struct gpio_chip *chip = irq_data_get_irq_chip_data(d); 2186 2187 if (chip->irq.irq_disable) 2188 chip->irq.irq_disable(d); 2189 else 2190 chip->irq.chip->irq_mask(d); 2191 gpiochip_disable_irq(chip, d->hwirq); 2192 } 2193 2194 static void gpiochip_set_irq_hooks(struct gpio_chip *gpiochip) 2195 { 2196 struct irq_chip *irqchip = gpiochip->irq.chip; 2197 2198 if (!irqchip->irq_request_resources && 2199 !irqchip->irq_release_resources) { 2200 irqchip->irq_request_resources = gpiochip_irq_reqres; 2201 irqchip->irq_release_resources = gpiochip_irq_relres; 2202 } 2203 if (WARN_ON(gpiochip->irq.irq_enable)) 2204 return; 2205 /* Check if the irqchip already has this hook... */ 2206 if (irqchip->irq_enable == gpiochip_irq_enable) { 2207 /* 2208 * ...and if so, give a gentle warning that this is bad 2209 * practice. 2210 */ 2211 chip_info(gpiochip, 2212 "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n"); 2213 return; 2214 } 2215 gpiochip->irq.irq_enable = irqchip->irq_enable; 2216 gpiochip->irq.irq_disable = irqchip->irq_disable; 2217 irqchip->irq_enable = gpiochip_irq_enable; 2218 irqchip->irq_disable = gpiochip_irq_disable; 2219 } 2220 2221 /** 2222 * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip 2223 * @gpiochip: the GPIO chip to add the IRQ chip to 2224 * @lock_key: lockdep class for IRQ lock 2225 * @request_key: lockdep class for IRQ request 2226 */ 2227 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip, 2228 struct lock_class_key *lock_key, 2229 struct lock_class_key *request_key) 2230 { 2231 struct irq_chip *irqchip = gpiochip->irq.chip; 2232 const struct irq_domain_ops *ops = NULL; 2233 struct device_node *np; 2234 unsigned int type; 2235 unsigned int i; 2236 2237 if (!irqchip) 2238 return 0; 2239 2240 if (gpiochip->irq.parent_handler && gpiochip->can_sleep) { 2241 chip_err(gpiochip, "you cannot have chained interrupts on a chip that may sleep\n"); 2242 return -EINVAL; 2243 } 2244 2245 np = gpiochip->gpiodev->dev.of_node; 2246 type = gpiochip->irq.default_type; 2247 2248 /* 2249 * Specifying a default trigger is a terrible idea if DT or ACPI is 2250 * used to configure the interrupts, as you may end up with 2251 * conflicting triggers. Tell the user, and reset to NONE. 2252 */ 2253 if (WARN(np && type != IRQ_TYPE_NONE, 2254 "%s: Ignoring %u default trigger\n", np->full_name, type)) 2255 type = IRQ_TYPE_NONE; 2256 2257 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) { 2258 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent), 2259 "Ignoring %u default trigger\n", type); 2260 type = IRQ_TYPE_NONE; 2261 } 2262 2263 gpiochip->to_irq = gpiochip_to_irq; 2264 gpiochip->irq.default_type = type; 2265 gpiochip->irq.lock_key = lock_key; 2266 gpiochip->irq.request_key = request_key; 2267 2268 /* If a parent irqdomain is provided, let's build a hierarchy */ 2269 if (gpiochip_hierarchy_is_hierarchical(gpiochip)) { 2270 int ret = gpiochip_hierarchy_add_domain(gpiochip); 2271 if (ret) 2272 return ret; 2273 } else { 2274 /* Some drivers provide custom irqdomain ops */ 2275 if (gpiochip->irq.domain_ops) 2276 ops = gpiochip->irq.domain_ops; 2277 2278 if (!ops) 2279 ops = &gpiochip_domain_ops; 2280 gpiochip->irq.domain = irq_domain_add_simple(np, 2281 gpiochip->ngpio, 2282 gpiochip->irq.first, 2283 ops, gpiochip); 2284 if (!gpiochip->irq.domain) 2285 return -EINVAL; 2286 } 2287 2288 if (gpiochip->irq.parent_handler) { 2289 void *data = gpiochip->irq.parent_handler_data ?: gpiochip; 2290 2291 for (i = 0; i < gpiochip->irq.num_parents; i++) { 2292 /* 2293 * The parent IRQ chip is already using the chip_data 2294 * for this IRQ chip, so our callbacks simply use the 2295 * handler_data. 2296 */ 2297 irq_set_chained_handler_and_data(gpiochip->irq.parents[i], 2298 gpiochip->irq.parent_handler, 2299 data); 2300 } 2301 } 2302 2303 gpiochip_set_irq_hooks(gpiochip); 2304 2305 acpi_gpiochip_request_interrupts(gpiochip); 2306 2307 return 0; 2308 } 2309 2310 /** 2311 * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip 2312 * @gpiochip: the gpiochip to remove the irqchip from 2313 * 2314 * This is called only from gpiochip_remove() 2315 */ 2316 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) 2317 { 2318 struct irq_chip *irqchip = gpiochip->irq.chip; 2319 unsigned int offset; 2320 2321 acpi_gpiochip_free_interrupts(gpiochip); 2322 2323 if (irqchip && gpiochip->irq.parent_handler) { 2324 struct gpio_irq_chip *irq = &gpiochip->irq; 2325 unsigned int i; 2326 2327 for (i = 0; i < irq->num_parents; i++) 2328 irq_set_chained_handler_and_data(irq->parents[i], 2329 NULL, NULL); 2330 } 2331 2332 /* Remove all IRQ mappings and delete the domain */ 2333 if (gpiochip->irq.domain) { 2334 unsigned int irq; 2335 2336 for (offset = 0; offset < gpiochip->ngpio; offset++) { 2337 if (!gpiochip_irqchip_irq_valid(gpiochip, offset)) 2338 continue; 2339 2340 irq = irq_find_mapping(gpiochip->irq.domain, offset); 2341 irq_dispose_mapping(irq); 2342 } 2343 2344 irq_domain_remove(gpiochip->irq.domain); 2345 } 2346 2347 if (irqchip) { 2348 if (irqchip->irq_request_resources == gpiochip_irq_reqres) { 2349 irqchip->irq_request_resources = NULL; 2350 irqchip->irq_release_resources = NULL; 2351 } 2352 if (irqchip->irq_enable == gpiochip_irq_enable) { 2353 irqchip->irq_enable = gpiochip->irq.irq_enable; 2354 irqchip->irq_disable = gpiochip->irq.irq_disable; 2355 } 2356 } 2357 gpiochip->irq.irq_enable = NULL; 2358 gpiochip->irq.irq_disable = NULL; 2359 gpiochip->irq.chip = NULL; 2360 2361 gpiochip_irqchip_free_valid_mask(gpiochip); 2362 } 2363 2364 /** 2365 * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip 2366 * @gpiochip: the gpiochip to add the irqchip to 2367 * @irqchip: the irqchip to add to the gpiochip 2368 * @first_irq: if not dynamically assigned, the base (first) IRQ to 2369 * allocate gpiochip irqs from 2370 * @handler: the irq handler to use (often a predefined irq core function) 2371 * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE 2372 * to have the core avoid setting up any default type in the hardware. 2373 * @threaded: whether this irqchip uses a nested thread handler 2374 * @lock_key: lockdep class for IRQ lock 2375 * @request_key: lockdep class for IRQ request 2376 * 2377 * This function closely associates a certain irqchip with a certain 2378 * gpiochip, providing an irq domain to translate the local IRQs to 2379 * global irqs in the gpiolib core, and making sure that the gpiochip 2380 * is passed as chip data to all related functions. Driver callbacks 2381 * need to use gpiochip_get_data() to get their local state containers back 2382 * from the gpiochip passed as chip data. An irqdomain will be stored 2383 * in the gpiochip that shall be used by the driver to handle IRQ number 2384 * translation. The gpiochip will need to be initialized and registered 2385 * before calling this function. 2386 * 2387 * This function will handle two cell:ed simple IRQs and assumes all 2388 * the pins on the gpiochip can generate a unique IRQ. Everything else 2389 * need to be open coded. 2390 */ 2391 int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip, 2392 struct irq_chip *irqchip, 2393 unsigned int first_irq, 2394 irq_flow_handler_t handler, 2395 unsigned int type, 2396 bool threaded, 2397 struct lock_class_key *lock_key, 2398 struct lock_class_key *request_key) 2399 { 2400 struct device_node *of_node; 2401 2402 if (!gpiochip || !irqchip) 2403 return -EINVAL; 2404 2405 if (!gpiochip->parent) { 2406 pr_err("missing gpiochip .dev parent pointer\n"); 2407 return -EINVAL; 2408 } 2409 gpiochip->irq.threaded = threaded; 2410 of_node = gpiochip->parent->of_node; 2411 #ifdef CONFIG_OF_GPIO 2412 /* 2413 * If the gpiochip has an assigned OF node this takes precedence 2414 * FIXME: get rid of this and use gpiochip->parent->of_node 2415 * everywhere 2416 */ 2417 if (gpiochip->of_node) 2418 of_node = gpiochip->of_node; 2419 #endif 2420 /* 2421 * Specifying a default trigger is a terrible idea if DT or ACPI is 2422 * used to configure the interrupts, as you may end-up with 2423 * conflicting triggers. Tell the user, and reset to NONE. 2424 */ 2425 if (WARN(of_node && type != IRQ_TYPE_NONE, 2426 "%pOF: Ignoring %d default trigger\n", of_node, type)) 2427 type = IRQ_TYPE_NONE; 2428 if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) { 2429 acpi_handle_warn(ACPI_HANDLE(gpiochip->parent), 2430 "Ignoring %d default trigger\n", type); 2431 type = IRQ_TYPE_NONE; 2432 } 2433 2434 gpiochip->irq.chip = irqchip; 2435 gpiochip->irq.handler = handler; 2436 gpiochip->irq.default_type = type; 2437 gpiochip->to_irq = gpiochip_to_irq; 2438 gpiochip->irq.lock_key = lock_key; 2439 gpiochip->irq.request_key = request_key; 2440 gpiochip->irq.domain = irq_domain_add_simple(of_node, 2441 gpiochip->ngpio, first_irq, 2442 &gpiochip_domain_ops, gpiochip); 2443 if (!gpiochip->irq.domain) { 2444 gpiochip->irq.chip = NULL; 2445 return -EINVAL; 2446 } 2447 2448 gpiochip_set_irq_hooks(gpiochip); 2449 2450 acpi_gpiochip_request_interrupts(gpiochip); 2451 2452 return 0; 2453 } 2454 EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key); 2455 2456 #else /* CONFIG_GPIOLIB_IRQCHIP */ 2457 2458 static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip, 2459 struct lock_class_key *lock_key, 2460 struct lock_class_key *request_key) 2461 { 2462 return 0; 2463 } 2464 static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {} 2465 2466 static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gpiochip) 2467 { 2468 return 0; 2469 } 2470 2471 static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip) 2472 { 2473 return 0; 2474 } 2475 static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip) 2476 { } 2477 2478 #endif /* CONFIG_GPIOLIB_IRQCHIP */ 2479 2480 /** 2481 * gpiochip_generic_request() - request the gpio function for a pin 2482 * @chip: the gpiochip owning the GPIO 2483 * @offset: the offset of the GPIO to request for GPIO function 2484 */ 2485 int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset) 2486 { 2487 return pinctrl_gpio_request(chip->gpiodev->base + offset); 2488 } 2489 EXPORT_SYMBOL_GPL(gpiochip_generic_request); 2490 2491 /** 2492 * gpiochip_generic_free() - free the gpio function from a pin 2493 * @chip: the gpiochip to request the gpio function for 2494 * @offset: the offset of the GPIO to free from GPIO function 2495 */ 2496 void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset) 2497 { 2498 pinctrl_gpio_free(chip->gpiodev->base + offset); 2499 } 2500 EXPORT_SYMBOL_GPL(gpiochip_generic_free); 2501 2502 /** 2503 * gpiochip_generic_config() - apply configuration for a pin 2504 * @chip: the gpiochip owning the GPIO 2505 * @offset: the offset of the GPIO to apply the configuration 2506 * @config: the configuration to be applied 2507 */ 2508 int gpiochip_generic_config(struct gpio_chip *chip, unsigned offset, 2509 unsigned long config) 2510 { 2511 return pinctrl_gpio_set_config(chip->gpiodev->base + offset, config); 2512 } 2513 EXPORT_SYMBOL_GPL(gpiochip_generic_config); 2514 2515 #ifdef CONFIG_PINCTRL 2516 2517 /** 2518 * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping 2519 * @chip: the gpiochip to add the range for 2520 * @pctldev: the pin controller to map to 2521 * @gpio_offset: the start offset in the current gpio_chip number space 2522 * @pin_group: name of the pin group inside the pin controller 2523 * 2524 * Calling this function directly from a DeviceTree-supported 2525 * pinctrl driver is DEPRECATED. Please see Section 2.1 of 2526 * Documentation/devicetree/bindings/gpio/gpio.txt on how to 2527 * bind pinctrl and gpio drivers via the "gpio-ranges" property. 2528 */ 2529 int gpiochip_add_pingroup_range(struct gpio_chip *chip, 2530 struct pinctrl_dev *pctldev, 2531 unsigned int gpio_offset, const char *pin_group) 2532 { 2533 struct gpio_pin_range *pin_range; 2534 struct gpio_device *gdev = chip->gpiodev; 2535 int ret; 2536 2537 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); 2538 if (!pin_range) { 2539 chip_err(chip, "failed to allocate pin ranges\n"); 2540 return -ENOMEM; 2541 } 2542 2543 /* Use local offset as range ID */ 2544 pin_range->range.id = gpio_offset; 2545 pin_range->range.gc = chip; 2546 pin_range->range.name = chip->label; 2547 pin_range->range.base = gdev->base + gpio_offset; 2548 pin_range->pctldev = pctldev; 2549 2550 ret = pinctrl_get_group_pins(pctldev, pin_group, 2551 &pin_range->range.pins, 2552 &pin_range->range.npins); 2553 if (ret < 0) { 2554 kfree(pin_range); 2555 return ret; 2556 } 2557 2558 pinctrl_add_gpio_range(pctldev, &pin_range->range); 2559 2560 chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n", 2561 gpio_offset, gpio_offset + pin_range->range.npins - 1, 2562 pinctrl_dev_get_devname(pctldev), pin_group); 2563 2564 list_add_tail(&pin_range->node, &gdev->pin_ranges); 2565 2566 return 0; 2567 } 2568 EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); 2569 2570 /** 2571 * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping 2572 * @chip: the gpiochip to add the range for 2573 * @pinctl_name: the dev_name() of the pin controller to map to 2574 * @gpio_offset: the start offset in the current gpio_chip number space 2575 * @pin_offset: the start offset in the pin controller number space 2576 * @npins: the number of pins from the offset of each pin space (GPIO and 2577 * pin controller) to accumulate in this range 2578 * 2579 * Returns: 2580 * 0 on success, or a negative error-code on failure. 2581 * 2582 * Calling this function directly from a DeviceTree-supported 2583 * pinctrl driver is DEPRECATED. Please see Section 2.1 of 2584 * Documentation/devicetree/bindings/gpio/gpio.txt on how to 2585 * bind pinctrl and gpio drivers via the "gpio-ranges" property. 2586 */ 2587 int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name, 2588 unsigned int gpio_offset, unsigned int pin_offset, 2589 unsigned int npins) 2590 { 2591 struct gpio_pin_range *pin_range; 2592 struct gpio_device *gdev = chip->gpiodev; 2593 int ret; 2594 2595 pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); 2596 if (!pin_range) { 2597 chip_err(chip, "failed to allocate pin ranges\n"); 2598 return -ENOMEM; 2599 } 2600 2601 /* Use local offset as range ID */ 2602 pin_range->range.id = gpio_offset; 2603 pin_range->range.gc = chip; 2604 pin_range->range.name = chip->label; 2605 pin_range->range.base = gdev->base + gpio_offset; 2606 pin_range->range.pin_base = pin_offset; 2607 pin_range->range.npins = npins; 2608 pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name, 2609 &pin_range->range); 2610 if (IS_ERR(pin_range->pctldev)) { 2611 ret = PTR_ERR(pin_range->pctldev); 2612 chip_err(chip, "could not create pin range\n"); 2613 kfree(pin_range); 2614 return ret; 2615 } 2616 chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n", 2617 gpio_offset, gpio_offset + npins - 1, 2618 pinctl_name, 2619 pin_offset, pin_offset + npins - 1); 2620 2621 list_add_tail(&pin_range->node, &gdev->pin_ranges); 2622 2623 return 0; 2624 } 2625 EXPORT_SYMBOL_GPL(gpiochip_add_pin_range); 2626 2627 /** 2628 * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings 2629 * @chip: the chip to remove all the mappings for 2630 */ 2631 void gpiochip_remove_pin_ranges(struct gpio_chip *chip) 2632 { 2633 struct gpio_pin_range *pin_range, *tmp; 2634 struct gpio_device *gdev = chip->gpiodev; 2635 2636 list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) { 2637 list_del(&pin_range->node); 2638 pinctrl_remove_gpio_range(pin_range->pctldev, 2639 &pin_range->range); 2640 kfree(pin_range); 2641 } 2642 } 2643 EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); 2644 2645 #endif /* CONFIG_PINCTRL */ 2646 2647 /* These "optional" allocation calls help prevent drivers from stomping 2648 * on each other, and help provide better diagnostics in debugfs. 2649 * They're called even less than the "set direction" calls. 2650 */ 2651 static int gpiod_request_commit(struct gpio_desc *desc, const char *label) 2652 { 2653 struct gpio_chip *chip = desc->gdev->chip; 2654 int ret; 2655 unsigned long flags; 2656 unsigned offset; 2657 2658 if (label) { 2659 label = kstrdup_const(label, GFP_KERNEL); 2660 if (!label) 2661 return -ENOMEM; 2662 } 2663 2664 spin_lock_irqsave(&gpio_lock, flags); 2665 2666 /* NOTE: gpio_request() can be called in early boot, 2667 * before IRQs are enabled, for non-sleeping (SOC) GPIOs. 2668 */ 2669 2670 if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) { 2671 desc_set_label(desc, label ? : "?"); 2672 ret = 0; 2673 } else { 2674 kfree_const(label); 2675 ret = -EBUSY; 2676 goto done; 2677 } 2678 2679 if (chip->request) { 2680 /* chip->request may sleep */ 2681 spin_unlock_irqrestore(&gpio_lock, flags); 2682 offset = gpio_chip_hwgpio(desc); 2683 if (gpiochip_line_is_valid(chip, offset)) 2684 ret = chip->request(chip, offset); 2685 else 2686 ret = -EINVAL; 2687 spin_lock_irqsave(&gpio_lock, flags); 2688 2689 if (ret < 0) { 2690 desc_set_label(desc, NULL); 2691 kfree_const(label); 2692 clear_bit(FLAG_REQUESTED, &desc->flags); 2693 goto done; 2694 } 2695 } 2696 if (chip->get_direction) { 2697 /* chip->get_direction may sleep */ 2698 spin_unlock_irqrestore(&gpio_lock, flags); 2699 gpiod_get_direction(desc); 2700 spin_lock_irqsave(&gpio_lock, flags); 2701 } 2702 done: 2703 spin_unlock_irqrestore(&gpio_lock, flags); 2704 return ret; 2705 } 2706 2707 /* 2708 * This descriptor validation needs to be inserted verbatim into each 2709 * function taking a descriptor, so we need to use a preprocessor 2710 * macro to avoid endless duplication. If the desc is NULL it is an 2711 * optional GPIO and calls should just bail out. 2712 */ 2713 static int validate_desc(const struct gpio_desc *desc, const char *func) 2714 { 2715 if (!desc) 2716 return 0; 2717 if (IS_ERR(desc)) { 2718 pr_warn("%s: invalid GPIO (errorpointer)\n", func); 2719 return PTR_ERR(desc); 2720 } 2721 if (!desc->gdev) { 2722 pr_warn("%s: invalid GPIO (no device)\n", func); 2723 return -EINVAL; 2724 } 2725 if (!desc->gdev->chip) { 2726 dev_warn(&desc->gdev->dev, 2727 "%s: backing chip is gone\n", func); 2728 return 0; 2729 } 2730 return 1; 2731 } 2732 2733 #define VALIDATE_DESC(desc) do { \ 2734 int __valid = validate_desc(desc, __func__); \ 2735 if (__valid <= 0) \ 2736 return __valid; \ 2737 } while (0) 2738 2739 #define VALIDATE_DESC_VOID(desc) do { \ 2740 int __valid = validate_desc(desc, __func__); \ 2741 if (__valid <= 0) \ 2742 return; \ 2743 } while (0) 2744 2745 int gpiod_request(struct gpio_desc *desc, const char *label) 2746 { 2747 int ret = -EPROBE_DEFER; 2748 struct gpio_device *gdev; 2749 2750 VALIDATE_DESC(desc); 2751 gdev = desc->gdev; 2752 2753 if (try_module_get(gdev->owner)) { 2754 ret = gpiod_request_commit(desc, label); 2755 if (ret < 0) 2756 module_put(gdev->owner); 2757 else 2758 get_device(&gdev->dev); 2759 } 2760 2761 if (ret) 2762 gpiod_dbg(desc, "%s: status %d\n", __func__, ret); 2763 2764 return ret; 2765 } 2766 2767 static bool gpiod_free_commit(struct gpio_desc *desc) 2768 { 2769 bool ret = false; 2770 unsigned long flags; 2771 struct gpio_chip *chip; 2772 2773 might_sleep(); 2774 2775 gpiod_unexport(desc); 2776 2777 spin_lock_irqsave(&gpio_lock, flags); 2778 2779 chip = desc->gdev->chip; 2780 if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) { 2781 if (chip->free) { 2782 spin_unlock_irqrestore(&gpio_lock, flags); 2783 might_sleep_if(chip->can_sleep); 2784 chip->free(chip, gpio_chip_hwgpio(desc)); 2785 spin_lock_irqsave(&gpio_lock, flags); 2786 } 2787 kfree_const(desc->label); 2788 desc_set_label(desc, NULL); 2789 clear_bit(FLAG_ACTIVE_LOW, &desc->flags); 2790 clear_bit(FLAG_REQUESTED, &desc->flags); 2791 clear_bit(FLAG_OPEN_DRAIN, &desc->flags); 2792 clear_bit(FLAG_OPEN_SOURCE, &desc->flags); 2793 clear_bit(FLAG_IS_HOGGED, &desc->flags); 2794 ret = true; 2795 } 2796 2797 spin_unlock_irqrestore(&gpio_lock, flags); 2798 return ret; 2799 } 2800 2801 void gpiod_free(struct gpio_desc *desc) 2802 { 2803 if (desc && desc->gdev && gpiod_free_commit(desc)) { 2804 module_put(desc->gdev->owner); 2805 put_device(&desc->gdev->dev); 2806 } else { 2807 WARN_ON(extra_checks); 2808 } 2809 } 2810 2811 /** 2812 * gpiochip_is_requested - return string iff signal was requested 2813 * @chip: controller managing the signal 2814 * @offset: of signal within controller's 0..(ngpio - 1) range 2815 * 2816 * Returns NULL if the GPIO is not currently requested, else a string. 2817 * The string returned is the label passed to gpio_request(); if none has been 2818 * passed it is a meaningless, non-NULL constant. 2819 * 2820 * This function is for use by GPIO controller drivers. The label can 2821 * help with diagnostics, and knowing that the signal is used as a GPIO 2822 * can help avoid accidentally multiplexing it to another controller. 2823 */ 2824 const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset) 2825 { 2826 struct gpio_desc *desc; 2827 2828 if (offset >= chip->ngpio) 2829 return NULL; 2830 2831 desc = &chip->gpiodev->descs[offset]; 2832 2833 if (test_bit(FLAG_REQUESTED, &desc->flags) == 0) 2834 return NULL; 2835 return desc->label; 2836 } 2837 EXPORT_SYMBOL_GPL(gpiochip_is_requested); 2838 2839 /** 2840 * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor 2841 * @chip: GPIO chip 2842 * @hwnum: hardware number of the GPIO for which to request the descriptor 2843 * @label: label for the GPIO 2844 * @lflags: lookup flags for this GPIO or 0 if default, this can be used to 2845 * specify things like line inversion semantics with the machine flags 2846 * such as GPIO_OUT_LOW 2847 * @dflags: descriptor request flags for this GPIO or 0 if default, this 2848 * can be used to specify consumer semantics such as open drain 2849 * 2850 * Function allows GPIO chip drivers to request and use their own GPIO 2851 * descriptors via gpiolib API. Difference to gpiod_request() is that this 2852 * function will not increase reference count of the GPIO chip module. This 2853 * allows the GPIO chip module to be unloaded as needed (we assume that the 2854 * GPIO chip driver handles freeing the GPIOs it has requested). 2855 * 2856 * Returns: 2857 * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error 2858 * code on failure. 2859 */ 2860 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum, 2861 const char *label, 2862 enum gpio_lookup_flags lflags, 2863 enum gpiod_flags dflags) 2864 { 2865 struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum); 2866 int ret; 2867 2868 if (IS_ERR(desc)) { 2869 chip_err(chip, "failed to get GPIO descriptor\n"); 2870 return desc; 2871 } 2872 2873 ret = gpiod_request_commit(desc, label); 2874 if (ret < 0) 2875 return ERR_PTR(ret); 2876 2877 ret = gpiod_configure_flags(desc, label, lflags, dflags); 2878 if (ret) { 2879 chip_err(chip, "setup of own GPIO %s failed\n", label); 2880 gpiod_free_commit(desc); 2881 return ERR_PTR(ret); 2882 } 2883 2884 return desc; 2885 } 2886 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc); 2887 2888 /** 2889 * gpiochip_free_own_desc - Free GPIO requested by the chip driver 2890 * @desc: GPIO descriptor to free 2891 * 2892 * Function frees the given GPIO requested previously with 2893 * gpiochip_request_own_desc(). 2894 */ 2895 void gpiochip_free_own_desc(struct gpio_desc *desc) 2896 { 2897 if (desc) 2898 gpiod_free_commit(desc); 2899 } 2900 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc); 2901 2902 /* 2903 * Drivers MUST set GPIO direction before making get/set calls. In 2904 * some cases this is done in early boot, before IRQs are enabled. 2905 * 2906 * As a rule these aren't called more than once (except for drivers 2907 * using the open-drain emulation idiom) so these are natural places 2908 * to accumulate extra debugging checks. Note that we can't (yet) 2909 * rely on gpio_request() having been called beforehand. 2910 */ 2911 2912 static int gpio_set_config(struct gpio_chip *gc, unsigned offset, 2913 enum pin_config_param mode) 2914 { 2915 unsigned long config; 2916 unsigned arg; 2917 2918 switch (mode) { 2919 case PIN_CONFIG_BIAS_PULL_DOWN: 2920 case PIN_CONFIG_BIAS_PULL_UP: 2921 arg = 1; 2922 break; 2923 2924 default: 2925 arg = 0; 2926 } 2927 2928 config = PIN_CONF_PACKED(mode, arg); 2929 return gc->set_config ? gc->set_config(gc, offset, config) : -ENOTSUPP; 2930 } 2931 2932 /** 2933 * gpiod_direction_input - set the GPIO direction to input 2934 * @desc: GPIO to set to input 2935 * 2936 * Set the direction of the passed GPIO to input, such as gpiod_get_value() can 2937 * be called safely on it. 2938 * 2939 * Return 0 in case of success, else an error code. 2940 */ 2941 int gpiod_direction_input(struct gpio_desc *desc) 2942 { 2943 struct gpio_chip *chip; 2944 int ret = 0; 2945 2946 VALIDATE_DESC(desc); 2947 chip = desc->gdev->chip; 2948 2949 /* 2950 * It is legal to have no .get() and .direction_input() specified if 2951 * the chip is output-only, but you can't specify .direction_input() 2952 * and not support the .get() operation, that doesn't make sense. 2953 */ 2954 if (!chip->get && chip->direction_input) { 2955 gpiod_warn(desc, 2956 "%s: missing get() but have direction_input()\n", 2957 __func__); 2958 return -EIO; 2959 } 2960 2961 /* 2962 * If we have a .direction_input() callback, things are simple, 2963 * just call it. Else we are some input-only chip so try to check the 2964 * direction (if .get_direction() is supported) else we silently 2965 * assume we are in input mode after this. 2966 */ 2967 if (chip->direction_input) { 2968 ret = chip->direction_input(chip, gpio_chip_hwgpio(desc)); 2969 } else if (chip->get_direction && 2970 (chip->get_direction(chip, gpio_chip_hwgpio(desc)) != 1)) { 2971 gpiod_warn(desc, 2972 "%s: missing direction_input() operation and line is output\n", 2973 __func__); 2974 return -EIO; 2975 } 2976 if (ret == 0) 2977 clear_bit(FLAG_IS_OUT, &desc->flags); 2978 2979 if (test_bit(FLAG_PULL_UP, &desc->flags)) 2980 gpio_set_config(chip, gpio_chip_hwgpio(desc), 2981 PIN_CONFIG_BIAS_PULL_UP); 2982 else if (test_bit(FLAG_PULL_DOWN, &desc->flags)) 2983 gpio_set_config(chip, gpio_chip_hwgpio(desc), 2984 PIN_CONFIG_BIAS_PULL_DOWN); 2985 2986 trace_gpio_direction(desc_to_gpio(desc), 1, ret); 2987 2988 return ret; 2989 } 2990 EXPORT_SYMBOL_GPL(gpiod_direction_input); 2991 2992 static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value) 2993 { 2994 struct gpio_chip *gc = desc->gdev->chip; 2995 int val = !!value; 2996 int ret = 0; 2997 2998 /* 2999 * It's OK not to specify .direction_output() if the gpiochip is 3000 * output-only, but if there is then not even a .set() operation it 3001 * is pretty tricky to drive the output line. 3002 */ 3003 if (!gc->set && !gc->direction_output) { 3004 gpiod_warn(desc, 3005 "%s: missing set() and direction_output() operations\n", 3006 __func__); 3007 return -EIO; 3008 } 3009 3010 if (gc->direction_output) { 3011 ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val); 3012 } else { 3013 /* Check that we are in output mode if we can */ 3014 if (gc->get_direction && 3015 gc->get_direction(gc, gpio_chip_hwgpio(desc))) { 3016 gpiod_warn(desc, 3017 "%s: missing direction_output() operation\n", 3018 __func__); 3019 return -EIO; 3020 } 3021 /* 3022 * If we can't actively set the direction, we are some 3023 * output-only chip, so just drive the output as desired. 3024 */ 3025 gc->set(gc, gpio_chip_hwgpio(desc), val); 3026 } 3027 3028 if (!ret) 3029 set_bit(FLAG_IS_OUT, &desc->flags); 3030 trace_gpio_value(desc_to_gpio(desc), 0, val); 3031 trace_gpio_direction(desc_to_gpio(desc), 0, ret); 3032 return ret; 3033 } 3034 3035 /** 3036 * gpiod_direction_output_raw - set the GPIO direction to output 3037 * @desc: GPIO to set to output 3038 * @value: initial output value of the GPIO 3039 * 3040 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can 3041 * be called safely on it. The initial value of the output must be specified 3042 * as raw value on the physical line without regard for the ACTIVE_LOW status. 3043 * 3044 * Return 0 in case of success, else an error code. 3045 */ 3046 int gpiod_direction_output_raw(struct gpio_desc *desc, int value) 3047 { 3048 VALIDATE_DESC(desc); 3049 return gpiod_direction_output_raw_commit(desc, value); 3050 } 3051 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); 3052 3053 /** 3054 * gpiod_direction_output - set the GPIO direction to output 3055 * @desc: GPIO to set to output 3056 * @value: initial output value of the GPIO 3057 * 3058 * Set the direction of the passed GPIO to output, such as gpiod_set_value() can 3059 * be called safely on it. The initial value of the output must be specified 3060 * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into 3061 * account. 3062 * 3063 * Return 0 in case of success, else an error code. 3064 */ 3065 int gpiod_direction_output(struct gpio_desc *desc, int value) 3066 { 3067 struct gpio_chip *gc; 3068 int ret; 3069 3070 VALIDATE_DESC(desc); 3071 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) 3072 value = !value; 3073 else 3074 value = !!value; 3075 3076 /* GPIOs used for enabled IRQs shall not be set as output */ 3077 if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) && 3078 test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) { 3079 gpiod_err(desc, 3080 "%s: tried to set a GPIO tied to an IRQ as output\n", 3081 __func__); 3082 return -EIO; 3083 } 3084 3085 gc = desc->gdev->chip; 3086 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) { 3087 /* First see if we can enable open drain in hardware */ 3088 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc), 3089 PIN_CONFIG_DRIVE_OPEN_DRAIN); 3090 if (!ret) 3091 goto set_output_value; 3092 /* Emulate open drain by not actively driving the line high */ 3093 if (value) { 3094 ret = gpiod_direction_input(desc); 3095 goto set_output_flag; 3096 } 3097 } 3098 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) { 3099 ret = gpio_set_config(gc, gpio_chip_hwgpio(desc), 3100 PIN_CONFIG_DRIVE_OPEN_SOURCE); 3101 if (!ret) 3102 goto set_output_value; 3103 /* Emulate open source by not actively driving the line low */ 3104 if (!value) { 3105 ret = gpiod_direction_input(desc); 3106 goto set_output_flag; 3107 } 3108 } else { 3109 gpio_set_config(gc, gpio_chip_hwgpio(desc), 3110 PIN_CONFIG_DRIVE_PUSH_PULL); 3111 } 3112 3113 set_output_value: 3114 return gpiod_direction_output_raw_commit(desc, value); 3115 3116 set_output_flag: 3117 /* 3118 * When emulating open-source or open-drain functionalities by not 3119 * actively driving the line (setting mode to input) we still need to 3120 * set the IS_OUT flag or otherwise we won't be able to set the line 3121 * value anymore. 3122 */ 3123 if (ret == 0) 3124 set_bit(FLAG_IS_OUT, &desc->flags); 3125 return ret; 3126 } 3127 EXPORT_SYMBOL_GPL(gpiod_direction_output); 3128 3129 /** 3130 * gpiod_set_debounce - sets @debounce time for a GPIO 3131 * @desc: descriptor of the GPIO for which to set debounce time 3132 * @debounce: debounce time in microseconds 3133 * 3134 * Returns: 3135 * 0 on success, %-ENOTSUPP if the controller doesn't support setting the 3136 * debounce time. 3137 */ 3138 int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) 3139 { 3140 struct gpio_chip *chip; 3141 unsigned long config; 3142 3143 VALIDATE_DESC(desc); 3144 chip = desc->gdev->chip; 3145 if (!chip->set || !chip->set_config) { 3146 gpiod_dbg(desc, 3147 "%s: missing set() or set_config() operations\n", 3148 __func__); 3149 return -ENOTSUPP; 3150 } 3151 3152 config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce); 3153 return chip->set_config(chip, gpio_chip_hwgpio(desc), config); 3154 } 3155 EXPORT_SYMBOL_GPL(gpiod_set_debounce); 3156 3157 /** 3158 * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset 3159 * @desc: descriptor of the GPIO for which to configure persistence 3160 * @transitory: True to lose state on suspend or reset, false for persistence 3161 * 3162 * Returns: 3163 * 0 on success, otherwise a negative error code. 3164 */ 3165 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory) 3166 { 3167 struct gpio_chip *chip; 3168 unsigned long packed; 3169 int gpio; 3170 int rc; 3171 3172 VALIDATE_DESC(desc); 3173 /* 3174 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for 3175 * persistence state. 3176 */ 3177 if (transitory) 3178 set_bit(FLAG_TRANSITORY, &desc->flags); 3179 else 3180 clear_bit(FLAG_TRANSITORY, &desc->flags); 3181 3182 /* If the driver supports it, set the persistence state now */ 3183 chip = desc->gdev->chip; 3184 if (!chip->set_config) 3185 return 0; 3186 3187 packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE, 3188 !transitory); 3189 gpio = gpio_chip_hwgpio(desc); 3190 rc = chip->set_config(chip, gpio, packed); 3191 if (rc == -ENOTSUPP) { 3192 dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n", 3193 gpio); 3194 return 0; 3195 } 3196 3197 return rc; 3198 } 3199 EXPORT_SYMBOL_GPL(gpiod_set_transitory); 3200 3201 /** 3202 * gpiod_is_active_low - test whether a GPIO is active-low or not 3203 * @desc: the gpio descriptor to test 3204 * 3205 * Returns 1 if the GPIO is active-low, 0 otherwise. 3206 */ 3207 int gpiod_is_active_low(const struct gpio_desc *desc) 3208 { 3209 VALIDATE_DESC(desc); 3210 return test_bit(FLAG_ACTIVE_LOW, &desc->flags); 3211 } 3212 EXPORT_SYMBOL_GPL(gpiod_is_active_low); 3213 3214 /* I/O calls are only valid after configuration completed; the relevant 3215 * "is this a valid GPIO" error checks should already have been done. 3216 * 3217 * "Get" operations are often inlinable as reading a pin value register, 3218 * and masking the relevant bit in that register. 3219 * 3220 * When "set" operations are inlinable, they involve writing that mask to 3221 * one register to set a low value, or a different register to set it high. 3222 * Otherwise locking is needed, so there may be little value to inlining. 3223 * 3224 *------------------------------------------------------------------------ 3225 * 3226 * IMPORTANT!!! The hot paths -- get/set value -- assume that callers 3227 * have requested the GPIO. That can include implicit requesting by 3228 * a direction setting call. Marking a gpio as requested locks its chip 3229 * in memory, guaranteeing that these table lookups need no more locking 3230 * and that gpiochip_remove() will fail. 3231 * 3232 * REVISIT when debugging, consider adding some instrumentation to ensure 3233 * that the GPIO was actually requested. 3234 */ 3235 3236 static int gpiod_get_raw_value_commit(const struct gpio_desc *desc) 3237 { 3238 struct gpio_chip *chip; 3239 int offset; 3240 int value; 3241 3242 chip = desc->gdev->chip; 3243 offset = gpio_chip_hwgpio(desc); 3244 value = chip->get ? chip->get(chip, offset) : -EIO; 3245 value = value < 0 ? value : !!value; 3246 trace_gpio_value(desc_to_gpio(desc), 1, value); 3247 return value; 3248 } 3249 3250 static int gpio_chip_get_multiple(struct gpio_chip *chip, 3251 unsigned long *mask, unsigned long *bits) 3252 { 3253 if (chip->get_multiple) { 3254 return chip->get_multiple(chip, mask, bits); 3255 } else if (chip->get) { 3256 int i, value; 3257 3258 for_each_set_bit(i, mask, chip->ngpio) { 3259 value = chip->get(chip, i); 3260 if (value < 0) 3261 return value; 3262 __assign_bit(i, bits, value); 3263 } 3264 return 0; 3265 } 3266 return -EIO; 3267 } 3268 3269 int gpiod_get_array_value_complex(bool raw, bool can_sleep, 3270 unsigned int array_size, 3271 struct gpio_desc **desc_array, 3272 struct gpio_array *array_info, 3273 unsigned long *value_bitmap) 3274 { 3275 int ret, i = 0; 3276 3277 /* 3278 * Validate array_info against desc_array and its size. 3279 * It should immediately follow desc_array if both 3280 * have been obtained from the same gpiod_get_array() call. 3281 */ 3282 if (array_info && array_info->desc == desc_array && 3283 array_size <= array_info->size && 3284 (void *)array_info == desc_array + array_info->size) { 3285 if (!can_sleep) 3286 WARN_ON(array_info->chip->can_sleep); 3287 3288 ret = gpio_chip_get_multiple(array_info->chip, 3289 array_info->get_mask, 3290 value_bitmap); 3291 if (ret) 3292 return ret; 3293 3294 if (!raw && !bitmap_empty(array_info->invert_mask, array_size)) 3295 bitmap_xor(value_bitmap, value_bitmap, 3296 array_info->invert_mask, array_size); 3297 3298 if (bitmap_full(array_info->get_mask, array_size)) 3299 return 0; 3300 3301 i = find_first_zero_bit(array_info->get_mask, array_size); 3302 } else { 3303 array_info = NULL; 3304 } 3305 3306 while (i < array_size) { 3307 struct gpio_chip *chip = desc_array[i]->gdev->chip; 3308 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)]; 3309 unsigned long *mask, *bits; 3310 int first, j, ret; 3311 3312 if (likely(chip->ngpio <= FASTPATH_NGPIO)) { 3313 mask = fastpath; 3314 } else { 3315 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio), 3316 sizeof(*mask), 3317 can_sleep ? GFP_KERNEL : GFP_ATOMIC); 3318 if (!mask) 3319 return -ENOMEM; 3320 } 3321 3322 bits = mask + BITS_TO_LONGS(chip->ngpio); 3323 bitmap_zero(mask, chip->ngpio); 3324 3325 if (!can_sleep) 3326 WARN_ON(chip->can_sleep); 3327 3328 /* collect all inputs belonging to the same chip */ 3329 first = i; 3330 do { 3331 const struct gpio_desc *desc = desc_array[i]; 3332 int hwgpio = gpio_chip_hwgpio(desc); 3333 3334 __set_bit(hwgpio, mask); 3335 i++; 3336 3337 if (array_info) 3338 i = find_next_zero_bit(array_info->get_mask, 3339 array_size, i); 3340 } while ((i < array_size) && 3341 (desc_array[i]->gdev->chip == chip)); 3342 3343 ret = gpio_chip_get_multiple(chip, mask, bits); 3344 if (ret) { 3345 if (mask != fastpath) 3346 kfree(mask); 3347 return ret; 3348 } 3349 3350 for (j = first; j < i; ) { 3351 const struct gpio_desc *desc = desc_array[j]; 3352 int hwgpio = gpio_chip_hwgpio(desc); 3353 int value = test_bit(hwgpio, bits); 3354 3355 if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags)) 3356 value = !value; 3357 __assign_bit(j, value_bitmap, value); 3358 trace_gpio_value(desc_to_gpio(desc), 1, value); 3359 j++; 3360 3361 if (array_info) 3362 j = find_next_zero_bit(array_info->get_mask, i, 3363 j); 3364 } 3365 3366 if (mask != fastpath) 3367 kfree(mask); 3368 } 3369 return 0; 3370 } 3371 3372 /** 3373 * gpiod_get_raw_value() - return a gpio's raw value 3374 * @desc: gpio whose value will be returned 3375 * 3376 * Return the GPIO's raw value, i.e. the value of the physical line disregarding 3377 * its ACTIVE_LOW status, or negative errno on failure. 3378 * 3379 * This function can be called from contexts where we cannot sleep, and will 3380 * complain if the GPIO chip functions potentially sleep. 3381 */ 3382 int gpiod_get_raw_value(const struct gpio_desc *desc) 3383 { 3384 VALIDATE_DESC(desc); 3385 /* Should be using gpiod_get_raw_value_cansleep() */ 3386 WARN_ON(desc->gdev->chip->can_sleep); 3387 return gpiod_get_raw_value_commit(desc); 3388 } 3389 EXPORT_SYMBOL_GPL(gpiod_get_raw_value); 3390 3391 /** 3392 * gpiod_get_value() - return a gpio's value 3393 * @desc: gpio whose value will be returned 3394 * 3395 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into 3396 * account, or negative errno on failure. 3397 * 3398 * This function can be called from contexts where we cannot sleep, and will 3399 * complain if the GPIO chip functions potentially sleep. 3400 */ 3401 int gpiod_get_value(const struct gpio_desc *desc) 3402 { 3403 int value; 3404 3405 VALIDATE_DESC(desc); 3406 /* Should be using gpiod_get_value_cansleep() */ 3407 WARN_ON(desc->gdev->chip->can_sleep); 3408 3409 value = gpiod_get_raw_value_commit(desc); 3410 if (value < 0) 3411 return value; 3412 3413 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) 3414 value = !value; 3415 3416 return value; 3417 } 3418 EXPORT_SYMBOL_GPL(gpiod_get_value); 3419 3420 /** 3421 * gpiod_get_raw_array_value() - read raw values from an array of GPIOs 3422 * @array_size: number of elements in the descriptor array / value bitmap 3423 * @desc_array: array of GPIO descriptors whose values will be read 3424 * @array_info: information on applicability of fast bitmap processing path 3425 * @value_bitmap: bitmap to store the read values 3426 * 3427 * Read the raw values of the GPIOs, i.e. the values of the physical lines 3428 * without regard for their ACTIVE_LOW status. Return 0 in case of success, 3429 * else an error code. 3430 * 3431 * This function can be called from contexts where we cannot sleep, 3432 * and it will complain if the GPIO chip functions potentially sleep. 3433 */ 3434 int gpiod_get_raw_array_value(unsigned int array_size, 3435 struct gpio_desc **desc_array, 3436 struct gpio_array *array_info, 3437 unsigned long *value_bitmap) 3438 { 3439 if (!desc_array) 3440 return -EINVAL; 3441 return gpiod_get_array_value_complex(true, false, array_size, 3442 desc_array, array_info, 3443 value_bitmap); 3444 } 3445 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value); 3446 3447 /** 3448 * gpiod_get_array_value() - read values from an array of GPIOs 3449 * @array_size: number of elements in the descriptor array / value bitmap 3450 * @desc_array: array of GPIO descriptors whose values will be read 3451 * @array_info: information on applicability of fast bitmap processing path 3452 * @value_bitmap: bitmap to store the read values 3453 * 3454 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status 3455 * into account. Return 0 in case of success, else an error code. 3456 * 3457 * This function can be called from contexts where we cannot sleep, 3458 * and it will complain if the GPIO chip functions potentially sleep. 3459 */ 3460 int gpiod_get_array_value(unsigned int array_size, 3461 struct gpio_desc **desc_array, 3462 struct gpio_array *array_info, 3463 unsigned long *value_bitmap) 3464 { 3465 if (!desc_array) 3466 return -EINVAL; 3467 return gpiod_get_array_value_complex(false, false, array_size, 3468 desc_array, array_info, 3469 value_bitmap); 3470 } 3471 EXPORT_SYMBOL_GPL(gpiod_get_array_value); 3472 3473 /* 3474 * gpio_set_open_drain_value_commit() - Set the open drain gpio's value. 3475 * @desc: gpio descriptor whose state need to be set. 3476 * @value: Non-zero for setting it HIGH otherwise it will set to LOW. 3477 */ 3478 static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value) 3479 { 3480 int ret = 0; 3481 struct gpio_chip *chip = desc->gdev->chip; 3482 int offset = gpio_chip_hwgpio(desc); 3483 3484 if (value) { 3485 ret = chip->direction_input(chip, offset); 3486 } else { 3487 ret = chip->direction_output(chip, offset, 0); 3488 if (!ret) 3489 set_bit(FLAG_IS_OUT, &desc->flags); 3490 } 3491 trace_gpio_direction(desc_to_gpio(desc), value, ret); 3492 if (ret < 0) 3493 gpiod_err(desc, 3494 "%s: Error in set_value for open drain err %d\n", 3495 __func__, ret); 3496 } 3497 3498 /* 3499 * _gpio_set_open_source_value() - Set the open source gpio's value. 3500 * @desc: gpio descriptor whose state need to be set. 3501 * @value: Non-zero for setting it HIGH otherwise it will set to LOW. 3502 */ 3503 static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value) 3504 { 3505 int ret = 0; 3506 struct gpio_chip *chip = desc->gdev->chip; 3507 int offset = gpio_chip_hwgpio(desc); 3508 3509 if (value) { 3510 ret = chip->direction_output(chip, offset, 1); 3511 if (!ret) 3512 set_bit(FLAG_IS_OUT, &desc->flags); 3513 } else { 3514 ret = chip->direction_input(chip, offset); 3515 } 3516 trace_gpio_direction(desc_to_gpio(desc), !value, ret); 3517 if (ret < 0) 3518 gpiod_err(desc, 3519 "%s: Error in set_value for open source err %d\n", 3520 __func__, ret); 3521 } 3522 3523 static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value) 3524 { 3525 struct gpio_chip *chip; 3526 3527 chip = desc->gdev->chip; 3528 trace_gpio_value(desc_to_gpio(desc), 0, value); 3529 chip->set(chip, gpio_chip_hwgpio(desc), value); 3530 } 3531 3532 /* 3533 * set multiple outputs on the same chip; 3534 * use the chip's set_multiple function if available; 3535 * otherwise set the outputs sequentially; 3536 * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word 3537 * defines which outputs are to be changed 3538 * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word 3539 * defines the values the outputs specified by mask are to be set to 3540 */ 3541 static void gpio_chip_set_multiple(struct gpio_chip *chip, 3542 unsigned long *mask, unsigned long *bits) 3543 { 3544 if (chip->set_multiple) { 3545 chip->set_multiple(chip, mask, bits); 3546 } else { 3547 unsigned int i; 3548 3549 /* set outputs if the corresponding mask bit is set */ 3550 for_each_set_bit(i, mask, chip->ngpio) 3551 chip->set(chip, i, test_bit(i, bits)); 3552 } 3553 } 3554 3555 int gpiod_set_array_value_complex(bool raw, bool can_sleep, 3556 unsigned int array_size, 3557 struct gpio_desc **desc_array, 3558 struct gpio_array *array_info, 3559 unsigned long *value_bitmap) 3560 { 3561 int i = 0; 3562 3563 /* 3564 * Validate array_info against desc_array and its size. 3565 * It should immediately follow desc_array if both 3566 * have been obtained from the same gpiod_get_array() call. 3567 */ 3568 if (array_info && array_info->desc == desc_array && 3569 array_size <= array_info->size && 3570 (void *)array_info == desc_array + array_info->size) { 3571 if (!can_sleep) 3572 WARN_ON(array_info->chip->can_sleep); 3573 3574 if (!raw && !bitmap_empty(array_info->invert_mask, array_size)) 3575 bitmap_xor(value_bitmap, value_bitmap, 3576 array_info->invert_mask, array_size); 3577 3578 gpio_chip_set_multiple(array_info->chip, array_info->set_mask, 3579 value_bitmap); 3580 3581 if (bitmap_full(array_info->set_mask, array_size)) 3582 return 0; 3583 3584 i = find_first_zero_bit(array_info->set_mask, array_size); 3585 } else { 3586 array_info = NULL; 3587 } 3588 3589 while (i < array_size) { 3590 struct gpio_chip *chip = desc_array[i]->gdev->chip; 3591 unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)]; 3592 unsigned long *mask, *bits; 3593 int count = 0; 3594 3595 if (likely(chip->ngpio <= FASTPATH_NGPIO)) { 3596 mask = fastpath; 3597 } else { 3598 mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio), 3599 sizeof(*mask), 3600 can_sleep ? GFP_KERNEL : GFP_ATOMIC); 3601 if (!mask) 3602 return -ENOMEM; 3603 } 3604 3605 bits = mask + BITS_TO_LONGS(chip->ngpio); 3606 bitmap_zero(mask, chip->ngpio); 3607 3608 if (!can_sleep) 3609 WARN_ON(chip->can_sleep); 3610 3611 do { 3612 struct gpio_desc *desc = desc_array[i]; 3613 int hwgpio = gpio_chip_hwgpio(desc); 3614 int value = test_bit(i, value_bitmap); 3615 3616 /* 3617 * Pins applicable for fast input but not for 3618 * fast output processing may have been already 3619 * inverted inside the fast path, skip them. 3620 */ 3621 if (!raw && !(array_info && 3622 test_bit(i, array_info->invert_mask)) && 3623 test_bit(FLAG_ACTIVE_LOW, &desc->flags)) 3624 value = !value; 3625 trace_gpio_value(desc_to_gpio(desc), 0, value); 3626 /* 3627 * collect all normal outputs belonging to the same chip 3628 * open drain and open source outputs are set individually 3629 */ 3630 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) { 3631 gpio_set_open_drain_value_commit(desc, value); 3632 } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) { 3633 gpio_set_open_source_value_commit(desc, value); 3634 } else { 3635 __set_bit(hwgpio, mask); 3636 if (value) 3637 __set_bit(hwgpio, bits); 3638 else 3639 __clear_bit(hwgpio, bits); 3640 count++; 3641 } 3642 i++; 3643 3644 if (array_info) 3645 i = find_next_zero_bit(array_info->set_mask, 3646 array_size, i); 3647 } while ((i < array_size) && 3648 (desc_array[i]->gdev->chip == chip)); 3649 /* push collected bits to outputs */ 3650 if (count != 0) 3651 gpio_chip_set_multiple(chip, mask, bits); 3652 3653 if (mask != fastpath) 3654 kfree(mask); 3655 } 3656 return 0; 3657 } 3658 3659 /** 3660 * gpiod_set_raw_value() - assign a gpio's raw value 3661 * @desc: gpio whose value will be assigned 3662 * @value: value to assign 3663 * 3664 * Set the raw value of the GPIO, i.e. the value of its physical line without 3665 * regard for its ACTIVE_LOW status. 3666 * 3667 * This function can be called from contexts where we cannot sleep, and will 3668 * complain if the GPIO chip functions potentially sleep. 3669 */ 3670 void gpiod_set_raw_value(struct gpio_desc *desc, int value) 3671 { 3672 VALIDATE_DESC_VOID(desc); 3673 /* Should be using gpiod_set_raw_value_cansleep() */ 3674 WARN_ON(desc->gdev->chip->can_sleep); 3675 gpiod_set_raw_value_commit(desc, value); 3676 } 3677 EXPORT_SYMBOL_GPL(gpiod_set_raw_value); 3678 3679 /** 3680 * gpiod_set_value_nocheck() - set a GPIO line value without checking 3681 * @desc: the descriptor to set the value on 3682 * @value: value to set 3683 * 3684 * This sets the value of a GPIO line backing a descriptor, applying 3685 * different semantic quirks like active low and open drain/source 3686 * handling. 3687 */ 3688 static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value) 3689 { 3690 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) 3691 value = !value; 3692 if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) 3693 gpio_set_open_drain_value_commit(desc, value); 3694 else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) 3695 gpio_set_open_source_value_commit(desc, value); 3696 else 3697 gpiod_set_raw_value_commit(desc, value); 3698 } 3699 3700 /** 3701 * gpiod_set_value() - assign a gpio's value 3702 * @desc: gpio whose value will be assigned 3703 * @value: value to assign 3704 * 3705 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW, 3706 * OPEN_DRAIN and OPEN_SOURCE flags into account. 3707 * 3708 * This function can be called from contexts where we cannot sleep, and will 3709 * complain if the GPIO chip functions potentially sleep. 3710 */ 3711 void gpiod_set_value(struct gpio_desc *desc, int value) 3712 { 3713 VALIDATE_DESC_VOID(desc); 3714 /* Should be using gpiod_set_value_cansleep() */ 3715 WARN_ON(desc->gdev->chip->can_sleep); 3716 gpiod_set_value_nocheck(desc, value); 3717 } 3718 EXPORT_SYMBOL_GPL(gpiod_set_value); 3719 3720 /** 3721 * gpiod_set_raw_array_value() - assign values to an array of GPIOs 3722 * @array_size: number of elements in the descriptor array / value bitmap 3723 * @desc_array: array of GPIO descriptors whose values will be assigned 3724 * @array_info: information on applicability of fast bitmap processing path 3725 * @value_bitmap: bitmap of values to assign 3726 * 3727 * Set the raw values of the GPIOs, i.e. the values of the physical lines 3728 * without regard for their ACTIVE_LOW status. 3729 * 3730 * This function can be called from contexts where we cannot sleep, and will 3731 * complain if the GPIO chip functions potentially sleep. 3732 */ 3733 int gpiod_set_raw_array_value(unsigned int array_size, 3734 struct gpio_desc **desc_array, 3735 struct gpio_array *array_info, 3736 unsigned long *value_bitmap) 3737 { 3738 if (!desc_array) 3739 return -EINVAL; 3740 return gpiod_set_array_value_complex(true, false, array_size, 3741 desc_array, array_info, value_bitmap); 3742 } 3743 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value); 3744 3745 /** 3746 * gpiod_set_array_value() - assign values to an array of GPIOs 3747 * @array_size: number of elements in the descriptor array / value bitmap 3748 * @desc_array: array of GPIO descriptors whose values will be assigned 3749 * @array_info: information on applicability of fast bitmap processing path 3750 * @value_bitmap: bitmap of values to assign 3751 * 3752 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status 3753 * into account. 3754 * 3755 * This function can be called from contexts where we cannot sleep, and will 3756 * complain if the GPIO chip functions potentially sleep. 3757 */ 3758 int gpiod_set_array_value(unsigned int array_size, 3759 struct gpio_desc **desc_array, 3760 struct gpio_array *array_info, 3761 unsigned long *value_bitmap) 3762 { 3763 if (!desc_array) 3764 return -EINVAL; 3765 return gpiod_set_array_value_complex(false, false, array_size, 3766 desc_array, array_info, 3767 value_bitmap); 3768 } 3769 EXPORT_SYMBOL_GPL(gpiod_set_array_value); 3770 3771 /** 3772 * gpiod_cansleep() - report whether gpio value access may sleep 3773 * @desc: gpio to check 3774 * 3775 */ 3776 int gpiod_cansleep(const struct gpio_desc *desc) 3777 { 3778 VALIDATE_DESC(desc); 3779 return desc->gdev->chip->can_sleep; 3780 } 3781 EXPORT_SYMBOL_GPL(gpiod_cansleep); 3782 3783 /** 3784 * gpiod_set_consumer_name() - set the consumer name for the descriptor 3785 * @desc: gpio to set the consumer name on 3786 * @name: the new consumer name 3787 */ 3788 int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name) 3789 { 3790 VALIDATE_DESC(desc); 3791 if (name) { 3792 name = kstrdup_const(name, GFP_KERNEL); 3793 if (!name) 3794 return -ENOMEM; 3795 } 3796 3797 kfree_const(desc->label); 3798 desc_set_label(desc, name); 3799 3800 return 0; 3801 } 3802 EXPORT_SYMBOL_GPL(gpiod_set_consumer_name); 3803 3804 /** 3805 * gpiod_to_irq() - return the IRQ corresponding to a GPIO 3806 * @desc: gpio whose IRQ will be returned (already requested) 3807 * 3808 * Return the IRQ corresponding to the passed GPIO, or an error code in case of 3809 * error. 3810 */ 3811 int gpiod_to_irq(const struct gpio_desc *desc) 3812 { 3813 struct gpio_chip *chip; 3814 int offset; 3815 3816 /* 3817 * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics 3818 * requires this function to not return zero on an invalid descriptor 3819 * but rather a negative error number. 3820 */ 3821 if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip) 3822 return -EINVAL; 3823 3824 chip = desc->gdev->chip; 3825 offset = gpio_chip_hwgpio(desc); 3826 if (chip->to_irq) { 3827 int retirq = chip->to_irq(chip, offset); 3828 3829 /* Zero means NO_IRQ */ 3830 if (!retirq) 3831 return -ENXIO; 3832 3833 return retirq; 3834 } 3835 return -ENXIO; 3836 } 3837 EXPORT_SYMBOL_GPL(gpiod_to_irq); 3838 3839 /** 3840 * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ 3841 * @chip: the chip the GPIO to lock belongs to 3842 * @offset: the offset of the GPIO to lock as IRQ 3843 * 3844 * This is used directly by GPIO drivers that want to lock down 3845 * a certain GPIO line to be used for IRQs. 3846 */ 3847 int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset) 3848 { 3849 struct gpio_desc *desc; 3850 3851 desc = gpiochip_get_desc(chip, offset); 3852 if (IS_ERR(desc)) 3853 return PTR_ERR(desc); 3854 3855 /* 3856 * If it's fast: flush the direction setting if something changed 3857 * behind our back 3858 */ 3859 if (!chip->can_sleep && chip->get_direction) { 3860 int dir = gpiod_get_direction(desc); 3861 3862 if (dir < 0) { 3863 chip_err(chip, "%s: cannot get GPIO direction\n", 3864 __func__); 3865 return dir; 3866 } 3867 } 3868 3869 if (test_bit(FLAG_IS_OUT, &desc->flags)) { 3870 chip_err(chip, 3871 "%s: tried to flag a GPIO set as output for IRQ\n", 3872 __func__); 3873 return -EIO; 3874 } 3875 3876 set_bit(FLAG_USED_AS_IRQ, &desc->flags); 3877 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); 3878 3879 /* 3880 * If the consumer has not set up a label (such as when the 3881 * IRQ is referenced from .to_irq()) we set up a label here 3882 * so it is clear this is used as an interrupt. 3883 */ 3884 if (!desc->label) 3885 desc_set_label(desc, "interrupt"); 3886 3887 return 0; 3888 } 3889 EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq); 3890 3891 /** 3892 * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ 3893 * @chip: the chip the GPIO to lock belongs to 3894 * @offset: the offset of the GPIO to lock as IRQ 3895 * 3896 * This is used directly by GPIO drivers that want to indicate 3897 * that a certain GPIO is no longer used exclusively for IRQ. 3898 */ 3899 void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset) 3900 { 3901 struct gpio_desc *desc; 3902 3903 desc = gpiochip_get_desc(chip, offset); 3904 if (IS_ERR(desc)) 3905 return; 3906 3907 clear_bit(FLAG_USED_AS_IRQ, &desc->flags); 3908 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); 3909 3910 /* If we only had this marking, erase it */ 3911 if (desc->label && !strcmp(desc->label, "interrupt")) 3912 desc_set_label(desc, NULL); 3913 } 3914 EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq); 3915 3916 void gpiochip_disable_irq(struct gpio_chip *chip, unsigned int offset) 3917 { 3918 struct gpio_desc *desc = gpiochip_get_desc(chip, offset); 3919 3920 if (!IS_ERR(desc) && 3921 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) 3922 clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); 3923 } 3924 EXPORT_SYMBOL_GPL(gpiochip_disable_irq); 3925 3926 void gpiochip_enable_irq(struct gpio_chip *chip, unsigned int offset) 3927 { 3928 struct gpio_desc *desc = gpiochip_get_desc(chip, offset); 3929 3930 if (!IS_ERR(desc) && 3931 !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) { 3932 WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags)); 3933 set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); 3934 } 3935 } 3936 EXPORT_SYMBOL_GPL(gpiochip_enable_irq); 3937 3938 bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset) 3939 { 3940 if (offset >= chip->ngpio) 3941 return false; 3942 3943 return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags); 3944 } 3945 EXPORT_SYMBOL_GPL(gpiochip_line_is_irq); 3946 3947 int gpiochip_reqres_irq(struct gpio_chip *chip, unsigned int offset) 3948 { 3949 int ret; 3950 3951 if (!try_module_get(chip->gpiodev->owner)) 3952 return -ENODEV; 3953 3954 ret = gpiochip_lock_as_irq(chip, offset); 3955 if (ret) { 3956 chip_err(chip, "unable to lock HW IRQ %u for IRQ\n", offset); 3957 module_put(chip->gpiodev->owner); 3958 return ret; 3959 } 3960 return 0; 3961 } 3962 EXPORT_SYMBOL_GPL(gpiochip_reqres_irq); 3963 3964 void gpiochip_relres_irq(struct gpio_chip *chip, unsigned int offset) 3965 { 3966 gpiochip_unlock_as_irq(chip, offset); 3967 module_put(chip->gpiodev->owner); 3968 } 3969 EXPORT_SYMBOL_GPL(gpiochip_relres_irq); 3970 3971 bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset) 3972 { 3973 if (offset >= chip->ngpio) 3974 return false; 3975 3976 return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags); 3977 } 3978 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain); 3979 3980 bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset) 3981 { 3982 if (offset >= chip->ngpio) 3983 return false; 3984 3985 return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags); 3986 } 3987 EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source); 3988 3989 bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset) 3990 { 3991 if (offset >= chip->ngpio) 3992 return false; 3993 3994 return !test_bit(FLAG_TRANSITORY, &chip->gpiodev->descs[offset].flags); 3995 } 3996 EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent); 3997 3998 /** 3999 * gpiod_get_raw_value_cansleep() - return a gpio's raw value 4000 * @desc: gpio whose value will be returned 4001 * 4002 * Return the GPIO's raw value, i.e. the value of the physical line disregarding 4003 * its ACTIVE_LOW status, or negative errno on failure. 4004 * 4005 * This function is to be called from contexts that can sleep. 4006 */ 4007 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc) 4008 { 4009 might_sleep_if(extra_checks); 4010 VALIDATE_DESC(desc); 4011 return gpiod_get_raw_value_commit(desc); 4012 } 4013 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep); 4014 4015 /** 4016 * gpiod_get_value_cansleep() - return a gpio's value 4017 * @desc: gpio whose value will be returned 4018 * 4019 * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into 4020 * account, or negative errno on failure. 4021 * 4022 * This function is to be called from contexts that can sleep. 4023 */ 4024 int gpiod_get_value_cansleep(const struct gpio_desc *desc) 4025 { 4026 int value; 4027 4028 might_sleep_if(extra_checks); 4029 VALIDATE_DESC(desc); 4030 value = gpiod_get_raw_value_commit(desc); 4031 if (value < 0) 4032 return value; 4033 4034 if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) 4035 value = !value; 4036 4037 return value; 4038 } 4039 EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep); 4040 4041 /** 4042 * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs 4043 * @array_size: number of elements in the descriptor array / value bitmap 4044 * @desc_array: array of GPIO descriptors whose values will be read 4045 * @array_info: information on applicability of fast bitmap processing path 4046 * @value_bitmap: bitmap to store the read values 4047 * 4048 * Read the raw values of the GPIOs, i.e. the values of the physical lines 4049 * without regard for their ACTIVE_LOW status. Return 0 in case of success, 4050 * else an error code. 4051 * 4052 * This function is to be called from contexts that can sleep. 4053 */ 4054 int gpiod_get_raw_array_value_cansleep(unsigned int array_size, 4055 struct gpio_desc **desc_array, 4056 struct gpio_array *array_info, 4057 unsigned long *value_bitmap) 4058 { 4059 might_sleep_if(extra_checks); 4060 if (!desc_array) 4061 return -EINVAL; 4062 return gpiod_get_array_value_complex(true, true, array_size, 4063 desc_array, array_info, 4064 value_bitmap); 4065 } 4066 EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep); 4067 4068 /** 4069 * gpiod_get_array_value_cansleep() - read values from an array of GPIOs 4070 * @array_size: number of elements in the descriptor array / value bitmap 4071 * @desc_array: array of GPIO descriptors whose values will be read 4072 * @array_info: information on applicability of fast bitmap processing path 4073 * @value_bitmap: bitmap to store the read values 4074 * 4075 * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status 4076 * into account. Return 0 in case of success, else an error code. 4077 * 4078 * This function is to be called from contexts that can sleep. 4079 */ 4080 int gpiod_get_array_value_cansleep(unsigned int array_size, 4081 struct gpio_desc **desc_array, 4082 struct gpio_array *array_info, 4083 unsigned long *value_bitmap) 4084 { 4085 might_sleep_if(extra_checks); 4086 if (!desc_array) 4087 return -EINVAL; 4088 return gpiod_get_array_value_complex(false, true, array_size, 4089 desc_array, array_info, 4090 value_bitmap); 4091 } 4092 EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep); 4093 4094 /** 4095 * gpiod_set_raw_value_cansleep() - assign a gpio's raw value 4096 * @desc: gpio whose value will be assigned 4097 * @value: value to assign 4098 * 4099 * Set the raw value of the GPIO, i.e. the value of its physical line without 4100 * regard for its ACTIVE_LOW status. 4101 * 4102 * This function is to be called from contexts that can sleep. 4103 */ 4104 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) 4105 { 4106 might_sleep_if(extra_checks); 4107 VALIDATE_DESC_VOID(desc); 4108 gpiod_set_raw_value_commit(desc, value); 4109 } 4110 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep); 4111 4112 /** 4113 * gpiod_set_value_cansleep() - assign a gpio's value 4114 * @desc: gpio whose value will be assigned 4115 * @value: value to assign 4116 * 4117 * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into 4118 * account 4119 * 4120 * This function is to be called from contexts that can sleep. 4121 */ 4122 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value) 4123 { 4124 might_sleep_if(extra_checks); 4125 VALIDATE_DESC_VOID(desc); 4126 gpiod_set_value_nocheck(desc, value); 4127 } 4128 EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); 4129 4130 /** 4131 * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs 4132 * @array_size: number of elements in the descriptor array / value bitmap 4133 * @desc_array: array of GPIO descriptors whose values will be assigned 4134 * @array_info: information on applicability of fast bitmap processing path 4135 * @value_bitmap: bitmap of values to assign 4136 * 4137 * Set the raw values of the GPIOs, i.e. the values of the physical lines 4138 * without regard for their ACTIVE_LOW status. 4139 * 4140 * This function is to be called from contexts that can sleep. 4141 */ 4142 int gpiod_set_raw_array_value_cansleep(unsigned int array_size, 4143 struct gpio_desc **desc_array, 4144 struct gpio_array *array_info, 4145 unsigned long *value_bitmap) 4146 { 4147 might_sleep_if(extra_checks); 4148 if (!desc_array) 4149 return -EINVAL; 4150 return gpiod_set_array_value_complex(true, true, array_size, desc_array, 4151 array_info, value_bitmap); 4152 } 4153 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep); 4154 4155 /** 4156 * gpiod_add_lookup_tables() - register GPIO device consumers 4157 * @tables: list of tables of consumers to register 4158 * @n: number of tables in the list 4159 */ 4160 void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n) 4161 { 4162 unsigned int i; 4163 4164 mutex_lock(&gpio_lookup_lock); 4165 4166 for (i = 0; i < n; i++) 4167 list_add_tail(&tables[i]->list, &gpio_lookup_list); 4168 4169 mutex_unlock(&gpio_lookup_lock); 4170 } 4171 4172 /** 4173 * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs 4174 * @array_size: number of elements in the descriptor array / value bitmap 4175 * @desc_array: array of GPIO descriptors whose values will be assigned 4176 * @array_info: information on applicability of fast bitmap processing path 4177 * @value_bitmap: bitmap of values to assign 4178 * 4179 * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status 4180 * into account. 4181 * 4182 * This function is to be called from contexts that can sleep. 4183 */ 4184 int gpiod_set_array_value_cansleep(unsigned int array_size, 4185 struct gpio_desc **desc_array, 4186 struct gpio_array *array_info, 4187 unsigned long *value_bitmap) 4188 { 4189 might_sleep_if(extra_checks); 4190 if (!desc_array) 4191 return -EINVAL; 4192 return gpiod_set_array_value_complex(false, true, array_size, 4193 desc_array, array_info, 4194 value_bitmap); 4195 } 4196 EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep); 4197 4198 /** 4199 * gpiod_add_lookup_table() - register GPIO device consumers 4200 * @table: table of consumers to register 4201 */ 4202 void gpiod_add_lookup_table(struct gpiod_lookup_table *table) 4203 { 4204 mutex_lock(&gpio_lookup_lock); 4205 4206 list_add_tail(&table->list, &gpio_lookup_list); 4207 4208 mutex_unlock(&gpio_lookup_lock); 4209 } 4210 EXPORT_SYMBOL_GPL(gpiod_add_lookup_table); 4211 4212 /** 4213 * gpiod_remove_lookup_table() - unregister GPIO device consumers 4214 * @table: table of consumers to unregister 4215 */ 4216 void gpiod_remove_lookup_table(struct gpiod_lookup_table *table) 4217 { 4218 mutex_lock(&gpio_lookup_lock); 4219 4220 list_del(&table->list); 4221 4222 mutex_unlock(&gpio_lookup_lock); 4223 } 4224 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table); 4225 4226 /** 4227 * gpiod_add_hogs() - register a set of GPIO hogs from machine code 4228 * @hogs: table of gpio hog entries with a zeroed sentinel at the end 4229 */ 4230 void gpiod_add_hogs(struct gpiod_hog *hogs) 4231 { 4232 struct gpio_chip *chip; 4233 struct gpiod_hog *hog; 4234 4235 mutex_lock(&gpio_machine_hogs_mutex); 4236 4237 for (hog = &hogs[0]; hog->chip_label; hog++) { 4238 list_add_tail(&hog->list, &gpio_machine_hogs); 4239 4240 /* 4241 * The chip may have been registered earlier, so check if it 4242 * exists and, if so, try to hog the line now. 4243 */ 4244 chip = find_chip_by_name(hog->chip_label); 4245 if (chip) 4246 gpiochip_machine_hog(chip, hog); 4247 } 4248 4249 mutex_unlock(&gpio_machine_hogs_mutex); 4250 } 4251 EXPORT_SYMBOL_GPL(gpiod_add_hogs); 4252 4253 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev) 4254 { 4255 const char *dev_id = dev ? dev_name(dev) : NULL; 4256 struct gpiod_lookup_table *table; 4257 4258 mutex_lock(&gpio_lookup_lock); 4259 4260 list_for_each_entry(table, &gpio_lookup_list, list) { 4261 if (table->dev_id && dev_id) { 4262 /* 4263 * Valid strings on both ends, must be identical to have 4264 * a match 4265 */ 4266 if (!strcmp(table->dev_id, dev_id)) 4267 goto found; 4268 } else { 4269 /* 4270 * One of the pointers is NULL, so both must be to have 4271 * a match 4272 */ 4273 if (dev_id == table->dev_id) 4274 goto found; 4275 } 4276 } 4277 table = NULL; 4278 4279 found: 4280 mutex_unlock(&gpio_lookup_lock); 4281 return table; 4282 } 4283 4284 static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, 4285 unsigned int idx, unsigned long *flags) 4286 { 4287 struct gpio_desc *desc = ERR_PTR(-ENOENT); 4288 struct gpiod_lookup_table *table; 4289 struct gpiod_lookup *p; 4290 4291 table = gpiod_find_lookup_table(dev); 4292 if (!table) 4293 return desc; 4294 4295 for (p = &table->table[0]; p->chip_label; p++) { 4296 struct gpio_chip *chip; 4297 4298 /* idx must always match exactly */ 4299 if (p->idx != idx) 4300 continue; 4301 4302 /* If the lookup entry has a con_id, require exact match */ 4303 if (p->con_id && (!con_id || strcmp(p->con_id, con_id))) 4304 continue; 4305 4306 chip = find_chip_by_name(p->chip_label); 4307 4308 if (!chip) { 4309 /* 4310 * As the lookup table indicates a chip with 4311 * p->chip_label should exist, assume it may 4312 * still appear later and let the interested 4313 * consumer be probed again or let the Deferred 4314 * Probe infrastructure handle the error. 4315 */ 4316 dev_warn(dev, "cannot find GPIO chip %s, deferring\n", 4317 p->chip_label); 4318 return ERR_PTR(-EPROBE_DEFER); 4319 } 4320 4321 if (chip->ngpio <= p->chip_hwnum) { 4322 dev_err(dev, 4323 "requested GPIO %d is out of range [0..%d] for chip %s\n", 4324 idx, chip->ngpio, chip->label); 4325 return ERR_PTR(-EINVAL); 4326 } 4327 4328 desc = gpiochip_get_desc(chip, p->chip_hwnum); 4329 *flags = p->flags; 4330 4331 return desc; 4332 } 4333 4334 return desc; 4335 } 4336 4337 static int platform_gpio_count(struct device *dev, const char *con_id) 4338 { 4339 struct gpiod_lookup_table *table; 4340 struct gpiod_lookup *p; 4341 unsigned int count = 0; 4342 4343 table = gpiod_find_lookup_table(dev); 4344 if (!table) 4345 return -ENOENT; 4346 4347 for (p = &table->table[0]; p->chip_label; p++) { 4348 if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) || 4349 (!con_id && !p->con_id)) 4350 count++; 4351 } 4352 if (!count) 4353 return -ENOENT; 4354 4355 return count; 4356 } 4357 4358 /** 4359 * gpiod_count - return the number of GPIOs associated with a device / function 4360 * or -ENOENT if no GPIO has been assigned to the requested function 4361 * @dev: GPIO consumer, can be NULL for system-global GPIOs 4362 * @con_id: function within the GPIO consumer 4363 */ 4364 int gpiod_count(struct device *dev, const char *con_id) 4365 { 4366 int count = -ENOENT; 4367 4368 if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) 4369 count = of_gpio_get_count(dev, con_id); 4370 else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) 4371 count = acpi_gpio_count(dev, con_id); 4372 4373 if (count < 0) 4374 count = platform_gpio_count(dev, con_id); 4375 4376 return count; 4377 } 4378 EXPORT_SYMBOL_GPL(gpiod_count); 4379 4380 /** 4381 * gpiod_get - obtain a GPIO for a given GPIO function 4382 * @dev: GPIO consumer, can be NULL for system-global GPIOs 4383 * @con_id: function within the GPIO consumer 4384 * @flags: optional GPIO initialization flags 4385 * 4386 * Return the GPIO descriptor corresponding to the function con_id of device 4387 * dev, -ENOENT if no GPIO has been assigned to the requested function, or 4388 * another IS_ERR() code if an error occurred while trying to acquire the GPIO. 4389 */ 4390 struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id, 4391 enum gpiod_flags flags) 4392 { 4393 return gpiod_get_index(dev, con_id, 0, flags); 4394 } 4395 EXPORT_SYMBOL_GPL(gpiod_get); 4396 4397 /** 4398 * gpiod_get_optional - obtain an optional GPIO for a given GPIO function 4399 * @dev: GPIO consumer, can be NULL for system-global GPIOs 4400 * @con_id: function within the GPIO consumer 4401 * @flags: optional GPIO initialization flags 4402 * 4403 * This is equivalent to gpiod_get(), except that when no GPIO was assigned to 4404 * the requested function it will return NULL. This is convenient for drivers 4405 * that need to handle optional GPIOs. 4406 */ 4407 struct gpio_desc *__must_check gpiod_get_optional(struct device *dev, 4408 const char *con_id, 4409 enum gpiod_flags flags) 4410 { 4411 return gpiod_get_index_optional(dev, con_id, 0, flags); 4412 } 4413 EXPORT_SYMBOL_GPL(gpiod_get_optional); 4414 4415 4416 /** 4417 * gpiod_configure_flags - helper function to configure a given GPIO 4418 * @desc: gpio whose value will be assigned 4419 * @con_id: function within the GPIO consumer 4420 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from 4421 * of_find_gpio() or of_get_gpio_hog() 4422 * @dflags: gpiod_flags - optional GPIO initialization flags 4423 * 4424 * Return 0 on success, -ENOENT if no GPIO has been assigned to the 4425 * requested function and/or index, or another IS_ERR() code if an error 4426 * occurred while trying to acquire the GPIO. 4427 */ 4428 int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, 4429 unsigned long lflags, enum gpiod_flags dflags) 4430 { 4431 int ret; 4432 4433 if (lflags & GPIO_ACTIVE_LOW) 4434 set_bit(FLAG_ACTIVE_LOW, &desc->flags); 4435 4436 if (lflags & GPIO_OPEN_DRAIN) 4437 set_bit(FLAG_OPEN_DRAIN, &desc->flags); 4438 else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) { 4439 /* 4440 * This enforces open drain mode from the consumer side. 4441 * This is necessary for some busses like I2C, but the lookup 4442 * should *REALLY* have specified them as open drain in the 4443 * first place, so print a little warning here. 4444 */ 4445 set_bit(FLAG_OPEN_DRAIN, &desc->flags); 4446 gpiod_warn(desc, 4447 "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n"); 4448 } 4449 4450 if (lflags & GPIO_OPEN_SOURCE) 4451 set_bit(FLAG_OPEN_SOURCE, &desc->flags); 4452 4453 if ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) { 4454 gpiod_err(desc, 4455 "both pull-up and pull-down enabled, invalid configuration\n"); 4456 return -EINVAL; 4457 } 4458 4459 if (lflags & GPIO_PULL_UP) 4460 set_bit(FLAG_PULL_UP, &desc->flags); 4461 else if (lflags & GPIO_PULL_DOWN) 4462 set_bit(FLAG_PULL_DOWN, &desc->flags); 4463 4464 ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY)); 4465 if (ret < 0) 4466 return ret; 4467 4468 /* No particular flag request, return here... */ 4469 if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) { 4470 pr_debug("no flags found for %s\n", con_id); 4471 return 0; 4472 } 4473 4474 /* Process flags */ 4475 if (dflags & GPIOD_FLAGS_BIT_DIR_OUT) 4476 ret = gpiod_direction_output(desc, 4477 !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL)); 4478 else 4479 ret = gpiod_direction_input(desc); 4480 4481 return ret; 4482 } 4483 4484 /** 4485 * gpiod_get_index - obtain a GPIO from a multi-index GPIO function 4486 * @dev: GPIO consumer, can be NULL for system-global GPIOs 4487 * @con_id: function within the GPIO consumer 4488 * @idx: index of the GPIO to obtain in the consumer 4489 * @flags: optional GPIO initialization flags 4490 * 4491 * This variant of gpiod_get() allows to access GPIOs other than the first 4492 * defined one for functions that define several GPIOs. 4493 * 4494 * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the 4495 * requested function and/or index, or another IS_ERR() code if an error 4496 * occurred while trying to acquire the GPIO. 4497 */ 4498 struct gpio_desc *__must_check gpiod_get_index(struct device *dev, 4499 const char *con_id, 4500 unsigned int idx, 4501 enum gpiod_flags flags) 4502 { 4503 unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT; 4504 struct gpio_desc *desc = NULL; 4505 int ret; 4506 /* Maybe we have a device name, maybe not */ 4507 const char *devname = dev ? dev_name(dev) : "?"; 4508 4509 dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); 4510 4511 if (dev) { 4512 /* Using device tree? */ 4513 if (IS_ENABLED(CONFIG_OF) && dev->of_node) { 4514 dev_dbg(dev, "using device tree for GPIO lookup\n"); 4515 desc = of_find_gpio(dev, con_id, idx, &lookupflags); 4516 } else if (ACPI_COMPANION(dev)) { 4517 dev_dbg(dev, "using ACPI for GPIO lookup\n"); 4518 desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags); 4519 } 4520 } 4521 4522 /* 4523 * Either we are not using DT or ACPI, or their lookup did not return 4524 * a result. In that case, use platform lookup as a fallback. 4525 */ 4526 if (!desc || desc == ERR_PTR(-ENOENT)) { 4527 dev_dbg(dev, "using lookup tables for GPIO lookup\n"); 4528 desc = gpiod_find(dev, con_id, idx, &lookupflags); 4529 } 4530 4531 if (IS_ERR(desc)) { 4532 dev_dbg(dev, "No GPIO consumer %s found\n", con_id); 4533 return desc; 4534 } 4535 4536 /* 4537 * If a connection label was passed use that, else attempt to use 4538 * the device name as label 4539 */ 4540 ret = gpiod_request(desc, con_id ? con_id : devname); 4541 if (ret < 0) { 4542 if (ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) { 4543 /* 4544 * This happens when there are several consumers for 4545 * the same GPIO line: we just return here without 4546 * further initialization. It is a bit if a hack. 4547 * This is necessary to support fixed regulators. 4548 * 4549 * FIXME: Make this more sane and safe. 4550 */ 4551 dev_info(dev, "nonexclusive access to GPIO for %s\n", 4552 con_id ? con_id : devname); 4553 return desc; 4554 } else { 4555 return ERR_PTR(ret); 4556 } 4557 } 4558 4559 ret = gpiod_configure_flags(desc, con_id, lookupflags, flags); 4560 if (ret < 0) { 4561 dev_dbg(dev, "setup of GPIO %s failed\n", con_id); 4562 gpiod_put(desc); 4563 return ERR_PTR(ret); 4564 } 4565 4566 return desc; 4567 } 4568 EXPORT_SYMBOL_GPL(gpiod_get_index); 4569 4570 /** 4571 * fwnode_get_named_gpiod - obtain a GPIO from firmware node 4572 * @fwnode: handle of the firmware node 4573 * @propname: name of the firmware property representing the GPIO 4574 * @index: index of the GPIO to obtain for the consumer 4575 * @dflags: GPIO initialization flags 4576 * @label: label to attach to the requested GPIO 4577 * 4578 * This function can be used for drivers that get their configuration 4579 * from opaque firmware. 4580 * 4581 * The function properly finds the corresponding GPIO using whatever is the 4582 * underlying firmware interface and then makes sure that the GPIO 4583 * descriptor is requested before it is returned to the caller. 4584 * 4585 * Returns: 4586 * On successful request the GPIO pin is configured in accordance with 4587 * provided @dflags. 4588 * 4589 * In case of error an ERR_PTR() is returned. 4590 */ 4591 struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, 4592 const char *propname, int index, 4593 enum gpiod_flags dflags, 4594 const char *label) 4595 { 4596 unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT; 4597 struct gpio_desc *desc = ERR_PTR(-ENODEV); 4598 int ret; 4599 4600 if (!fwnode) 4601 return ERR_PTR(-EINVAL); 4602 4603 if (is_of_node(fwnode)) { 4604 desc = gpiod_get_from_of_node(to_of_node(fwnode), 4605 propname, index, 4606 dflags, 4607 label); 4608 return desc; 4609 } else if (is_acpi_node(fwnode)) { 4610 struct acpi_gpio_info info; 4611 4612 desc = acpi_node_get_gpiod(fwnode, propname, index, &info); 4613 if (IS_ERR(desc)) 4614 return desc; 4615 4616 acpi_gpio_update_gpiod_flags(&dflags, &info); 4617 acpi_gpio_update_gpiod_lookup_flags(&lflags, &info); 4618 } 4619 4620 /* Currently only ACPI takes this path */ 4621 ret = gpiod_request(desc, label); 4622 if (ret) 4623 return ERR_PTR(ret); 4624 4625 ret = gpiod_configure_flags(desc, propname, lflags, dflags); 4626 if (ret < 0) { 4627 gpiod_put(desc); 4628 return ERR_PTR(ret); 4629 } 4630 4631 return desc; 4632 } 4633 EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod); 4634 4635 /** 4636 * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO 4637 * function 4638 * @dev: GPIO consumer, can be NULL for system-global GPIOs 4639 * @con_id: function within the GPIO consumer 4640 * @index: index of the GPIO to obtain in the consumer 4641 * @flags: optional GPIO initialization flags 4642 * 4643 * This is equivalent to gpiod_get_index(), except that when no GPIO with the 4644 * specified index was assigned to the requested function it will return NULL. 4645 * This is convenient for drivers that need to handle optional GPIOs. 4646 */ 4647 struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev, 4648 const char *con_id, 4649 unsigned int index, 4650 enum gpiod_flags flags) 4651 { 4652 struct gpio_desc *desc; 4653 4654 desc = gpiod_get_index(dev, con_id, index, flags); 4655 if (IS_ERR(desc)) { 4656 if (PTR_ERR(desc) == -ENOENT) 4657 return NULL; 4658 } 4659 4660 return desc; 4661 } 4662 EXPORT_SYMBOL_GPL(gpiod_get_index_optional); 4663 4664 /** 4665 * gpiod_hog - Hog the specified GPIO desc given the provided flags 4666 * @desc: gpio whose value will be assigned 4667 * @name: gpio line name 4668 * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from 4669 * of_find_gpio() or of_get_gpio_hog() 4670 * @dflags: gpiod_flags - optional GPIO initialization flags 4671 */ 4672 int gpiod_hog(struct gpio_desc *desc, const char *name, 4673 unsigned long lflags, enum gpiod_flags dflags) 4674 { 4675 struct gpio_chip *chip; 4676 struct gpio_desc *local_desc; 4677 int hwnum; 4678 int ret; 4679 4680 chip = gpiod_to_chip(desc); 4681 hwnum = gpio_chip_hwgpio(desc); 4682 4683 local_desc = gpiochip_request_own_desc(chip, hwnum, name, 4684 lflags, dflags); 4685 if (IS_ERR(local_desc)) { 4686 ret = PTR_ERR(local_desc); 4687 pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n", 4688 name, chip->label, hwnum, ret); 4689 return ret; 4690 } 4691 4692 /* Mark GPIO as hogged so it can be identified and removed later */ 4693 set_bit(FLAG_IS_HOGGED, &desc->flags); 4694 4695 pr_info("GPIO line %d (%s) hogged as %s%s\n", 4696 desc_to_gpio(desc), name, 4697 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input", 4698 (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? 4699 (dflags&GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low":""); 4700 4701 return 0; 4702 } 4703 4704 /** 4705 * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog 4706 * @chip: gpio chip to act on 4707 */ 4708 static void gpiochip_free_hogs(struct gpio_chip *chip) 4709 { 4710 int id; 4711 4712 for (id = 0; id < chip->ngpio; id++) { 4713 if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags)) 4714 gpiochip_free_own_desc(&chip->gpiodev->descs[id]); 4715 } 4716 } 4717 4718 /** 4719 * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function 4720 * @dev: GPIO consumer, can be NULL for system-global GPIOs 4721 * @con_id: function within the GPIO consumer 4722 * @flags: optional GPIO initialization flags 4723 * 4724 * This function acquires all the GPIOs defined under a given function. 4725 * 4726 * Return a struct gpio_descs containing an array of descriptors, -ENOENT if 4727 * no GPIO has been assigned to the requested function, or another IS_ERR() 4728 * code if an error occurred while trying to acquire the GPIOs. 4729 */ 4730 struct gpio_descs *__must_check gpiod_get_array(struct device *dev, 4731 const char *con_id, 4732 enum gpiod_flags flags) 4733 { 4734 struct gpio_desc *desc; 4735 struct gpio_descs *descs; 4736 struct gpio_array *array_info = NULL; 4737 struct gpio_chip *chip; 4738 int count, bitmap_size; 4739 4740 count = gpiod_count(dev, con_id); 4741 if (count < 0) 4742 return ERR_PTR(count); 4743 4744 descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL); 4745 if (!descs) 4746 return ERR_PTR(-ENOMEM); 4747 4748 for (descs->ndescs = 0; descs->ndescs < count; ) { 4749 desc = gpiod_get_index(dev, con_id, descs->ndescs, flags); 4750 if (IS_ERR(desc)) { 4751 gpiod_put_array(descs); 4752 return ERR_CAST(desc); 4753 } 4754 4755 descs->desc[descs->ndescs] = desc; 4756 4757 chip = gpiod_to_chip(desc); 4758 /* 4759 * If pin hardware number of array member 0 is also 0, select 4760 * its chip as a candidate for fast bitmap processing path. 4761 */ 4762 if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) { 4763 struct gpio_descs *array; 4764 4765 bitmap_size = BITS_TO_LONGS(chip->ngpio > count ? 4766 chip->ngpio : count); 4767 4768 array = kzalloc(struct_size(descs, desc, count) + 4769 struct_size(array_info, invert_mask, 4770 3 * bitmap_size), GFP_KERNEL); 4771 if (!array) { 4772 gpiod_put_array(descs); 4773 return ERR_PTR(-ENOMEM); 4774 } 4775 4776 memcpy(array, descs, 4777 struct_size(descs, desc, descs->ndescs + 1)); 4778 kfree(descs); 4779 4780 descs = array; 4781 array_info = (void *)(descs->desc + count); 4782 array_info->get_mask = array_info->invert_mask + 4783 bitmap_size; 4784 array_info->set_mask = array_info->get_mask + 4785 bitmap_size; 4786 4787 array_info->desc = descs->desc; 4788 array_info->size = count; 4789 array_info->chip = chip; 4790 bitmap_set(array_info->get_mask, descs->ndescs, 4791 count - descs->ndescs); 4792 bitmap_set(array_info->set_mask, descs->ndescs, 4793 count - descs->ndescs); 4794 descs->info = array_info; 4795 } 4796 /* Unmark array members which don't belong to the 'fast' chip */ 4797 if (array_info && array_info->chip != chip) { 4798 __clear_bit(descs->ndescs, array_info->get_mask); 4799 __clear_bit(descs->ndescs, array_info->set_mask); 4800 } 4801 /* 4802 * Detect array members which belong to the 'fast' chip 4803 * but their pins are not in hardware order. 4804 */ 4805 else if (array_info && 4806 gpio_chip_hwgpio(desc) != descs->ndescs) { 4807 /* 4808 * Don't use fast path if all array members processed so 4809 * far belong to the same chip as this one but its pin 4810 * hardware number is different from its array index. 4811 */ 4812 if (bitmap_full(array_info->get_mask, descs->ndescs)) { 4813 array_info = NULL; 4814 } else { 4815 __clear_bit(descs->ndescs, 4816 array_info->get_mask); 4817 __clear_bit(descs->ndescs, 4818 array_info->set_mask); 4819 } 4820 } else if (array_info) { 4821 /* Exclude open drain or open source from fast output */ 4822 if (gpiochip_line_is_open_drain(chip, descs->ndescs) || 4823 gpiochip_line_is_open_source(chip, descs->ndescs)) 4824 __clear_bit(descs->ndescs, 4825 array_info->set_mask); 4826 /* Identify 'fast' pins which require invertion */ 4827 if (gpiod_is_active_low(desc)) 4828 __set_bit(descs->ndescs, 4829 array_info->invert_mask); 4830 } 4831 4832 descs->ndescs++; 4833 } 4834 if (array_info) 4835 dev_dbg(dev, 4836 "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n", 4837 array_info->chip->label, array_info->size, 4838 *array_info->get_mask, *array_info->set_mask, 4839 *array_info->invert_mask); 4840 return descs; 4841 } 4842 EXPORT_SYMBOL_GPL(gpiod_get_array); 4843 4844 /** 4845 * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO 4846 * function 4847 * @dev: GPIO consumer, can be NULL for system-global GPIOs 4848 * @con_id: function within the GPIO consumer 4849 * @flags: optional GPIO initialization flags 4850 * 4851 * This is equivalent to gpiod_get_array(), except that when no GPIO was 4852 * assigned to the requested function it will return NULL. 4853 */ 4854 struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev, 4855 const char *con_id, 4856 enum gpiod_flags flags) 4857 { 4858 struct gpio_descs *descs; 4859 4860 descs = gpiod_get_array(dev, con_id, flags); 4861 if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT)) 4862 return NULL; 4863 4864 return descs; 4865 } 4866 EXPORT_SYMBOL_GPL(gpiod_get_array_optional); 4867 4868 /** 4869 * gpiod_put - dispose of a GPIO descriptor 4870 * @desc: GPIO descriptor to dispose of 4871 * 4872 * No descriptor can be used after gpiod_put() has been called on it. 4873 */ 4874 void gpiod_put(struct gpio_desc *desc) 4875 { 4876 if (desc) 4877 gpiod_free(desc); 4878 } 4879 EXPORT_SYMBOL_GPL(gpiod_put); 4880 4881 /** 4882 * gpiod_put_array - dispose of multiple GPIO descriptors 4883 * @descs: struct gpio_descs containing an array of descriptors 4884 */ 4885 void gpiod_put_array(struct gpio_descs *descs) 4886 { 4887 unsigned int i; 4888 4889 for (i = 0; i < descs->ndescs; i++) 4890 gpiod_put(descs->desc[i]); 4891 4892 kfree(descs); 4893 } 4894 EXPORT_SYMBOL_GPL(gpiod_put_array); 4895 4896 static int __init gpiolib_dev_init(void) 4897 { 4898 int ret; 4899 4900 /* Register GPIO sysfs bus */ 4901 ret = bus_register(&gpio_bus_type); 4902 if (ret < 0) { 4903 pr_err("gpiolib: could not register GPIO bus type\n"); 4904 return ret; 4905 } 4906 4907 ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, "gpiochip"); 4908 if (ret < 0) { 4909 pr_err("gpiolib: failed to allocate char dev region\n"); 4910 bus_unregister(&gpio_bus_type); 4911 } else { 4912 gpiolib_initialized = true; 4913 gpiochip_setup_devs(); 4914 } 4915 return ret; 4916 } 4917 core_initcall(gpiolib_dev_init); 4918 4919 #ifdef CONFIG_DEBUG_FS 4920 4921 static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev) 4922 { 4923 unsigned i; 4924 struct gpio_chip *chip = gdev->chip; 4925 unsigned gpio = gdev->base; 4926 struct gpio_desc *gdesc = &gdev->descs[0]; 4927 bool is_out; 4928 bool is_irq; 4929 bool active_low; 4930 4931 for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) { 4932 if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) { 4933 if (gdesc->name) { 4934 seq_printf(s, " gpio-%-3d (%-20.20s)\n", 4935 gpio, gdesc->name); 4936 } 4937 continue; 4938 } 4939 4940 gpiod_get_direction(gdesc); 4941 is_out = test_bit(FLAG_IS_OUT, &gdesc->flags); 4942 is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags); 4943 active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags); 4944 seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s", 4945 gpio, gdesc->name ? gdesc->name : "", gdesc->label, 4946 is_out ? "out" : "in ", 4947 chip->get ? (chip->get(chip, i) ? "hi" : "lo") : "? ", 4948 is_irq ? "IRQ " : "", 4949 active_low ? "ACTIVE LOW" : ""); 4950 seq_printf(s, "\n"); 4951 } 4952 } 4953 4954 static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) 4955 { 4956 unsigned long flags; 4957 struct gpio_device *gdev = NULL; 4958 loff_t index = *pos; 4959 4960 s->private = ""; 4961 4962 spin_lock_irqsave(&gpio_lock, flags); 4963 list_for_each_entry(gdev, &gpio_devices, list) 4964 if (index-- == 0) { 4965 spin_unlock_irqrestore(&gpio_lock, flags); 4966 return gdev; 4967 } 4968 spin_unlock_irqrestore(&gpio_lock, flags); 4969 4970 return NULL; 4971 } 4972 4973 static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos) 4974 { 4975 unsigned long flags; 4976 struct gpio_device *gdev = v; 4977 void *ret = NULL; 4978 4979 spin_lock_irqsave(&gpio_lock, flags); 4980 if (list_is_last(&gdev->list, &gpio_devices)) 4981 ret = NULL; 4982 else 4983 ret = list_entry(gdev->list.next, struct gpio_device, list); 4984 spin_unlock_irqrestore(&gpio_lock, flags); 4985 4986 s->private = "\n"; 4987 ++*pos; 4988 4989 return ret; 4990 } 4991 4992 static void gpiolib_seq_stop(struct seq_file *s, void *v) 4993 { 4994 } 4995 4996 static int gpiolib_seq_show(struct seq_file *s, void *v) 4997 { 4998 struct gpio_device *gdev = v; 4999 struct gpio_chip *chip = gdev->chip; 5000 struct device *parent; 5001 5002 if (!chip) { 5003 seq_printf(s, "%s%s: (dangling chip)", (char *)s->private, 5004 dev_name(&gdev->dev)); 5005 return 0; 5006 } 5007 5008 seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private, 5009 dev_name(&gdev->dev), 5010 gdev->base, gdev->base + gdev->ngpio - 1); 5011 parent = chip->parent; 5012 if (parent) 5013 seq_printf(s, ", parent: %s/%s", 5014 parent->bus ? parent->bus->name : "no-bus", 5015 dev_name(parent)); 5016 if (chip->label) 5017 seq_printf(s, ", %s", chip->label); 5018 if (chip->can_sleep) 5019 seq_printf(s, ", can sleep"); 5020 seq_printf(s, ":\n"); 5021 5022 if (chip->dbg_show) 5023 chip->dbg_show(s, chip); 5024 else 5025 gpiolib_dbg_show(s, gdev); 5026 5027 return 0; 5028 } 5029 5030 static const struct seq_operations gpiolib_seq_ops = { 5031 .start = gpiolib_seq_start, 5032 .next = gpiolib_seq_next, 5033 .stop = gpiolib_seq_stop, 5034 .show = gpiolib_seq_show, 5035 }; 5036 5037 static int gpiolib_open(struct inode *inode, struct file *file) 5038 { 5039 return seq_open(file, &gpiolib_seq_ops); 5040 } 5041 5042 static const struct file_operations gpiolib_operations = { 5043 .owner = THIS_MODULE, 5044 .open = gpiolib_open, 5045 .read = seq_read, 5046 .llseek = seq_lseek, 5047 .release = seq_release, 5048 }; 5049 5050 static int __init gpiolib_debugfs_init(void) 5051 { 5052 /* /sys/kernel/debug/gpio */ 5053 debugfs_create_file("gpio", S_IFREG | S_IRUGO, NULL, NULL, 5054 &gpiolib_operations); 5055 return 0; 5056 } 5057 subsys_initcall(gpiolib_debugfs_init); 5058 5059 #endif /* DEBUG_FS */ 5060