1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * Driver for keys on GPIO lines capable of generating interrupts. 4 * 5 * Copyright 2005 Phil Blundell 6 * Copyright 2010, 2011 David Jander <david@protonic.nl> 7 */ 8 9#include <linux/module.h> 10 11#include <linux/init.h> 12#include <linux/fs.h> 13#include <linux/interrupt.h> 14#include <linux/irq.h> 15#include <linux/sched.h> 16#include <linux/pm.h> 17#include <linux/slab.h> 18#include <linux/sysctl.h> 19#include <linux/proc_fs.h> 20#include <linux/delay.h> 21#include <linux/platform_device.h> 22#include <linux/input.h> 23#include <linux/gpio_keys.h> 24#include <linux/workqueue.h> 25#include <linux/gpio.h> 26#include <linux/gpio/consumer.h> 27#include <linux/of.h> 28#include <linux/of_irq.h> 29#include <linux/spinlock.h> 30#include <dt-bindings/input/gpio-keys.h> 31 32struct gpio_button_data { 33 const struct gpio_keys_button *button; 34 struct input_dev *input; 35 struct gpio_desc *gpiod; 36 37 unsigned short *code; 38 39 struct timer_list release_timer; 40 unsigned int release_delay; /* in msecs, for IRQ-only buttons */ 41 42 struct delayed_work work; 43 unsigned int software_debounce; /* in msecs, for GPIO-driven buttons */ 44 45 unsigned int irq; 46 unsigned int wakeup_trigger_type; 47 spinlock_t lock; 48 bool disabled; 49 bool key_pressed; 50 bool suspended; 51}; 52 53struct gpio_keys_drvdata { 54 const struct gpio_keys_platform_data *pdata; 55 struct input_dev *input; 56 struct mutex disable_lock; 57 unsigned short *keymap; 58 struct gpio_button_data data[]; 59}; 60 61/* 62 * SYSFS interface for enabling/disabling keys and switches: 63 * 64 * There are 4 attributes under /sys/devices/platform/gpio-keys/ 65 * keys [ro] - bitmap of keys (EV_KEY) which can be 66 * disabled 67 * switches [ro] - bitmap of switches (EV_SW) which can be 68 * disabled 69 * disabled_keys [rw] - bitmap of keys currently disabled 70 * disabled_switches [rw] - bitmap of switches currently disabled 71 * 72 * Userland can change these values and hence disable event generation 73 * for each key (or switch). Disabling a key means its interrupt line 74 * is disabled. 75 * 76 * For example, if we have following switches set up as gpio-keys: 77 * SW_DOCK = 5 78 * SW_CAMERA_LENS_COVER = 9 79 * SW_KEYPAD_SLIDE = 10 80 * SW_FRONT_PROXIMITY = 11 81 * This is read from switches: 82 * 11-9,5 83 * Next we want to disable proximity (11) and dock (5), we write: 84 * 11,5 85 * to file disabled_switches. Now proximity and dock IRQs are disabled. 86 * This can be verified by reading the file disabled_switches: 87 * 11,5 88 * If we now want to enable proximity (11) switch we write: 89 * 5 90 * to disabled_switches. 91 * 92 * We can disable only those keys which don't allow sharing the irq. 93 */ 94 95/** 96 * get_n_events_by_type() - returns maximum number of events per @type 97 * @type: type of button (%EV_KEY, %EV_SW) 98 * 99 * Return value of this function can be used to allocate bitmap 100 * large enough to hold all bits for given type. 101 */ 102static int get_n_events_by_type(int type) 103{ 104 BUG_ON(type != EV_SW && type != EV_KEY); 105 106 return (type == EV_KEY) ? KEY_CNT : SW_CNT; 107} 108 109/** 110 * get_bm_events_by_type() - returns bitmap of supported events per @type 111 * @input: input device from which bitmap is retrieved 112 * @type: type of button (%EV_KEY, %EV_SW) 113 * 114 * Return value of this function can be used to allocate bitmap 115 * large enough to hold all bits for given type. 116 */ 117static const unsigned long *get_bm_events_by_type(struct input_dev *dev, 118 int type) 119{ 120 BUG_ON(type != EV_SW && type != EV_KEY); 121 122 return (type == EV_KEY) ? dev->keybit : dev->swbit; 123} 124 125/** 126 * gpio_keys_disable_button() - disables given GPIO button 127 * @bdata: button data for button to be disabled 128 * 129 * Disables button pointed by @bdata. This is done by masking 130 * IRQ line. After this function is called, button won't generate 131 * input events anymore. Note that one can only disable buttons 132 * that don't share IRQs. 133 * 134 * Make sure that @bdata->disable_lock is locked when entering 135 * this function to avoid races when concurrent threads are 136 * disabling buttons at the same time. 137 */ 138static void gpio_keys_disable_button(struct gpio_button_data *bdata) 139{ 140 if (!bdata->disabled) { 141 /* 142 * Disable IRQ and associated timer/work structure. 143 */ 144 disable_irq(bdata->irq); 145 146 if (bdata->gpiod) 147 cancel_delayed_work_sync(&bdata->work); 148 else 149 del_timer_sync(&bdata->release_timer); 150 151 bdata->disabled = true; 152 } 153} 154 155/** 156 * gpio_keys_enable_button() - enables given GPIO button 157 * @bdata: button data for button to be disabled 158 * 159 * Enables given button pointed by @bdata. 160 * 161 * Make sure that @bdata->disable_lock is locked when entering 162 * this function to avoid races with concurrent threads trying 163 * to enable the same button at the same time. 164 */ 165static void gpio_keys_enable_button(struct gpio_button_data *bdata) 166{ 167 if (bdata->disabled) { 168 enable_irq(bdata->irq); 169 bdata->disabled = false; 170 } 171} 172 173/** 174 * gpio_keys_attr_show_helper() - fill in stringified bitmap of buttons 175 * @ddata: pointer to drvdata 176 * @buf: buffer where stringified bitmap is written 177 * @type: button type (%EV_KEY, %EV_SW) 178 * @only_disabled: does caller want only those buttons that are 179 * currently disabled or all buttons that can be 180 * disabled 181 * 182 * This function writes buttons that can be disabled to @buf. If 183 * @only_disabled is true, then @buf contains only those buttons 184 * that are currently disabled. Returns 0 on success or negative 185 * errno on failure. 186 */ 187static ssize_t gpio_keys_attr_show_helper(struct gpio_keys_drvdata *ddata, 188 char *buf, unsigned int type, 189 bool only_disabled) 190{ 191 int n_events = get_n_events_by_type(type); 192 unsigned long *bits; 193 ssize_t ret; 194 int i; 195 196 bits = bitmap_zalloc(n_events, GFP_KERNEL); 197 if (!bits) 198 return -ENOMEM; 199 200 for (i = 0; i < ddata->pdata->nbuttons; i++) { 201 struct gpio_button_data *bdata = &ddata->data[i]; 202 203 if (bdata->button->type != type) 204 continue; 205 206 if (only_disabled && !bdata->disabled) 207 continue; 208 209 __set_bit(*bdata->code, bits); 210 } 211 212 ret = scnprintf(buf, PAGE_SIZE - 1, "%*pbl", n_events, bits); 213 buf[ret++] = '\n'; 214 buf[ret] = '\0'; 215 216 bitmap_free(bits); 217 218 return ret; 219} 220 221/** 222 * gpio_keys_attr_store_helper() - enable/disable buttons based on given bitmap 223 * @ddata: pointer to drvdata 224 * @buf: buffer from userspace that contains stringified bitmap 225 * @type: button type (%EV_KEY, %EV_SW) 226 * 227 * This function parses stringified bitmap from @buf and disables/enables 228 * GPIO buttons accordingly. Returns 0 on success and negative error 229 * on failure. 230 */ 231static ssize_t gpio_keys_attr_store_helper(struct gpio_keys_drvdata *ddata, 232 const char *buf, unsigned int type) 233{ 234 int n_events = get_n_events_by_type(type); 235 const unsigned long *bitmap = get_bm_events_by_type(ddata->input, type); 236 unsigned long *bits; 237 ssize_t error; 238 int i; 239 240 bits = bitmap_zalloc(n_events, GFP_KERNEL); 241 if (!bits) 242 return -ENOMEM; 243 244 error = bitmap_parselist(buf, bits, n_events); 245 if (error) 246 goto out; 247 248 /* First validate */ 249 if (!bitmap_subset(bits, bitmap, n_events)) { 250 error = -EINVAL; 251 goto out; 252 } 253 254 for (i = 0; i < ddata->pdata->nbuttons; i++) { 255 struct gpio_button_data *bdata = &ddata->data[i]; 256 257 if (bdata->button->type != type) 258 continue; 259 260 if (test_bit(*bdata->code, bits) && 261 !bdata->button->can_disable) { 262 error = -EINVAL; 263 goto out; 264 } 265 } 266 267 mutex_lock(&ddata->disable_lock); 268 269 for (i = 0; i < ddata->pdata->nbuttons; i++) { 270 struct gpio_button_data *bdata = &ddata->data[i]; 271 272 if (bdata->button->type != type) 273 continue; 274 275 if (test_bit(*bdata->code, bits)) 276 gpio_keys_disable_button(bdata); 277 else 278 gpio_keys_enable_button(bdata); 279 } 280 281 mutex_unlock(&ddata->disable_lock); 282 283out: 284 bitmap_free(bits); 285 return error; 286} 287 288#define ATTR_SHOW_FN(name, type, only_disabled) \ 289static ssize_t gpio_keys_show_##name(struct device *dev, \ 290 struct device_attribute *attr, \ 291 char *buf) \ 292{ \ 293 struct platform_device *pdev = to_platform_device(dev); \ 294 struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \ 295 \ 296 return gpio_keys_attr_show_helper(ddata, buf, \ 297 type, only_disabled); \ 298} 299 300ATTR_SHOW_FN(keys, EV_KEY, false); 301ATTR_SHOW_FN(switches, EV_SW, false); 302ATTR_SHOW_FN(disabled_keys, EV_KEY, true); 303ATTR_SHOW_FN(disabled_switches, EV_SW, true); 304 305/* 306 * ATTRIBUTES: 307 * 308 * /sys/devices/platform/gpio-keys/keys [ro] 309 * /sys/devices/platform/gpio-keys/switches [ro] 310 */ 311static DEVICE_ATTR(keys, S_IRUGO, gpio_keys_show_keys, NULL); 312static DEVICE_ATTR(switches, S_IRUGO, gpio_keys_show_switches, NULL); 313 314#define ATTR_STORE_FN(name, type) \ 315static ssize_t gpio_keys_store_##name(struct device *dev, \ 316 struct device_attribute *attr, \ 317 const char *buf, \ 318 size_t count) \ 319{ \ 320 struct platform_device *pdev = to_platform_device(dev); \ 321 struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \ 322 ssize_t error; \ 323 \ 324 error = gpio_keys_attr_store_helper(ddata, buf, type); \ 325 if (error) \ 326 return error; \ 327 \ 328 return count; \ 329} 330 331ATTR_STORE_FN(disabled_keys, EV_KEY); 332ATTR_STORE_FN(disabled_switches, EV_SW); 333 334/* 335 * ATTRIBUTES: 336 * 337 * /sys/devices/platform/gpio-keys/disabled_keys [rw] 338 * /sys/devices/platform/gpio-keys/disables_switches [rw] 339 */ 340static DEVICE_ATTR(disabled_keys, S_IWUSR | S_IRUGO, 341 gpio_keys_show_disabled_keys, 342 gpio_keys_store_disabled_keys); 343static DEVICE_ATTR(disabled_switches, S_IWUSR | S_IRUGO, 344 gpio_keys_show_disabled_switches, 345 gpio_keys_store_disabled_switches); 346 347static struct attribute *gpio_keys_attrs[] = { 348 &dev_attr_keys.attr, 349 &dev_attr_switches.attr, 350 &dev_attr_disabled_keys.attr, 351 &dev_attr_disabled_switches.attr, 352 NULL, 353}; 354ATTRIBUTE_GROUPS(gpio_keys); 355 356static void gpio_keys_gpio_report_event(struct gpio_button_data *bdata) 357{ 358 const struct gpio_keys_button *button = bdata->button; 359 struct input_dev *input = bdata->input; 360 unsigned int type = button->type ?: EV_KEY; 361 int state; 362 363 state = gpiod_get_value_cansleep(bdata->gpiod); 364 if (state < 0) { 365 dev_err(input->dev.parent, 366 "failed to get gpio state: %d\n", state); 367 return; 368 } 369 370 if (type == EV_ABS) { 371 if (state) 372 input_event(input, type, button->code, button->value); 373 } else { 374 input_event(input, type, *bdata->code, state); 375 } 376 input_sync(input); 377} 378 379static void gpio_keys_gpio_work_func(struct work_struct *work) 380{ 381 struct gpio_button_data *bdata = 382 container_of(work, struct gpio_button_data, work.work); 383 384 gpio_keys_gpio_report_event(bdata); 385 386 if (bdata->button->wakeup) 387 pm_relax(bdata->input->dev.parent); 388} 389 390static irqreturn_t gpio_keys_gpio_isr(int irq, void *dev_id) 391{ 392 struct gpio_button_data *bdata = dev_id; 393 394 BUG_ON(irq != bdata->irq); 395 396 if (bdata->button->wakeup) { 397 const struct gpio_keys_button *button = bdata->button; 398 399 pm_stay_awake(bdata->input->dev.parent); 400 if (bdata->suspended && 401 (button->type == 0 || button->type == EV_KEY)) { 402 /* 403 * Simulate wakeup key press in case the key has 404 * already released by the time we got interrupt 405 * handler to run. 406 */ 407 input_report_key(bdata->input, button->code, 1); 408 } 409 } 410 411 mod_delayed_work(system_wq, 412 &bdata->work, 413 msecs_to_jiffies(bdata->software_debounce)); 414 415 return IRQ_HANDLED; 416} 417 418static void gpio_keys_irq_timer(struct timer_list *t) 419{ 420 struct gpio_button_data *bdata = from_timer(bdata, t, release_timer); 421 struct input_dev *input = bdata->input; 422 unsigned long flags; 423 424 spin_lock_irqsave(&bdata->lock, flags); 425 if (bdata->key_pressed) { 426 input_event(input, EV_KEY, *bdata->code, 0); 427 input_sync(input); 428 bdata->key_pressed = false; 429 } 430 spin_unlock_irqrestore(&bdata->lock, flags); 431} 432 433static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id) 434{ 435 struct gpio_button_data *bdata = dev_id; 436 struct input_dev *input = bdata->input; 437 unsigned long flags; 438 439 BUG_ON(irq != bdata->irq); 440 441 spin_lock_irqsave(&bdata->lock, flags); 442 443 if (!bdata->key_pressed) { 444 if (bdata->button->wakeup) 445 pm_wakeup_event(bdata->input->dev.parent, 0); 446 447 input_event(input, EV_KEY, *bdata->code, 1); 448 input_sync(input); 449 450 if (!bdata->release_delay) { 451 input_event(input, EV_KEY, *bdata->code, 0); 452 input_sync(input); 453 goto out; 454 } 455 456 bdata->key_pressed = true; 457 } 458 459 if (bdata->release_delay) 460 mod_timer(&bdata->release_timer, 461 jiffies + msecs_to_jiffies(bdata->release_delay)); 462out: 463 spin_unlock_irqrestore(&bdata->lock, flags); 464 return IRQ_HANDLED; 465} 466 467static void gpio_keys_quiesce_key(void *data) 468{ 469 struct gpio_button_data *bdata = data; 470 471 if (bdata->gpiod) 472 cancel_delayed_work_sync(&bdata->work); 473 else 474 del_timer_sync(&bdata->release_timer); 475} 476 477static int gpio_keys_setup_key(struct platform_device *pdev, 478 struct input_dev *input, 479 struct gpio_keys_drvdata *ddata, 480 const struct gpio_keys_button *button, 481 int idx, 482 struct fwnode_handle *child) 483{ 484 const char *desc = button->desc ? button->desc : "gpio_keys"; 485 struct device *dev = &pdev->dev; 486 struct gpio_button_data *bdata = &ddata->data[idx]; 487 irq_handler_t isr; 488 unsigned long irqflags; 489 int irq; 490 int error; 491 492 bdata->input = input; 493 bdata->button = button; 494 spin_lock_init(&bdata->lock); 495 496 if (child) { 497 bdata->gpiod = devm_fwnode_gpiod_get(dev, child, 498 NULL, GPIOD_IN, desc); 499 if (IS_ERR(bdata->gpiod)) { 500 error = PTR_ERR(bdata->gpiod); 501 if (error == -ENOENT) { 502 /* 503 * GPIO is optional, we may be dealing with 504 * purely interrupt-driven setup. 505 */ 506 bdata->gpiod = NULL; 507 } else { 508 if (error != -EPROBE_DEFER) 509 dev_err(dev, "failed to get gpio: %d\n", 510 error); 511 return error; 512 } 513 } 514 } else if (gpio_is_valid(button->gpio)) { 515 /* 516 * Legacy GPIO number, so request the GPIO here and 517 * convert it to descriptor. 518 */ 519 unsigned flags = GPIOF_IN; 520 521 if (button->active_low) 522 flags |= GPIOF_ACTIVE_LOW; 523 524 error = devm_gpio_request_one(dev, button->gpio, flags, desc); 525 if (error < 0) { 526 dev_err(dev, "Failed to request GPIO %d, error %d\n", 527 button->gpio, error); 528 return error; 529 } 530 531 bdata->gpiod = gpio_to_desc(button->gpio); 532 if (!bdata->gpiod) 533 return -EINVAL; 534 } 535 536 if (bdata->gpiod) { 537 bool active_low = gpiod_is_active_low(bdata->gpiod); 538 539 if (button->debounce_interval) { 540 error = gpiod_set_debounce(bdata->gpiod, 541 button->debounce_interval * 1000); 542 /* use timer if gpiolib doesn't provide debounce */ 543 if (error < 0) 544 bdata->software_debounce = 545 button->debounce_interval; 546 } 547 548 if (button->irq) { 549 bdata->irq = button->irq; 550 } else { 551 irq = gpiod_to_irq(bdata->gpiod); 552 if (irq < 0) { 553 error = irq; 554 dev_err(dev, 555 "Unable to get irq number for GPIO %d, error %d\n", 556 button->gpio, error); 557 return error; 558 } 559 bdata->irq = irq; 560 } 561 562 INIT_DELAYED_WORK(&bdata->work, gpio_keys_gpio_work_func); 563 564 isr = gpio_keys_gpio_isr; 565 irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING; 566 567 switch (button->wakeup_event_action) { 568 case EV_ACT_ASSERTED: 569 bdata->wakeup_trigger_type = active_low ? 570 IRQ_TYPE_EDGE_FALLING : IRQ_TYPE_EDGE_RISING; 571 break; 572 case EV_ACT_DEASSERTED: 573 bdata->wakeup_trigger_type = active_low ? 574 IRQ_TYPE_EDGE_RISING : IRQ_TYPE_EDGE_FALLING; 575 break; 576 case EV_ACT_ANY: 577 default: 578 /* 579 * For other cases, we are OK letting suspend/resume 580 * not reconfigure the trigger type. 581 */ 582 break; 583 } 584 } else { 585 if (!button->irq) { 586 dev_err(dev, "Found button without gpio or irq\n"); 587 return -EINVAL; 588 } 589 590 bdata->irq = button->irq; 591 592 if (button->type && button->type != EV_KEY) { 593 dev_err(dev, "Only EV_KEY allowed for IRQ buttons.\n"); 594 return -EINVAL; 595 } 596 597 bdata->release_delay = button->debounce_interval; 598 timer_setup(&bdata->release_timer, gpio_keys_irq_timer, 0); 599 600 isr = gpio_keys_irq_isr; 601 irqflags = 0; 602 603 /* 604 * For IRQ buttons, there is no interrupt for release. 605 * So we don't need to reconfigure the trigger type for wakeup. 606 */ 607 } 608 609 bdata->code = &ddata->keymap[idx]; 610 *bdata->code = button->code; 611 input_set_capability(input, button->type ?: EV_KEY, *bdata->code); 612 613 /* 614 * Install custom action to cancel release timer and 615 * workqueue item. 616 */ 617 error = devm_add_action(dev, gpio_keys_quiesce_key, bdata); 618 if (error) { 619 dev_err(dev, "failed to register quiesce action, error: %d\n", 620 error); 621 return error; 622 } 623 624 /* 625 * If platform has specified that the button can be disabled, 626 * we don't want it to share the interrupt line. 627 */ 628 if (!button->can_disable) 629 irqflags |= IRQF_SHARED; 630 631 error = devm_request_any_context_irq(dev, bdata->irq, isr, irqflags, 632 desc, bdata); 633 if (error < 0) { 634 dev_err(dev, "Unable to claim irq %d; error %d\n", 635 bdata->irq, error); 636 return error; 637 } 638 639 return 0; 640} 641 642static void gpio_keys_report_state(struct gpio_keys_drvdata *ddata) 643{ 644 struct input_dev *input = ddata->input; 645 int i; 646 647 for (i = 0; i < ddata->pdata->nbuttons; i++) { 648 struct gpio_button_data *bdata = &ddata->data[i]; 649 if (bdata->gpiod) 650 gpio_keys_gpio_report_event(bdata); 651 } 652 input_sync(input); 653} 654 655static int gpio_keys_open(struct input_dev *input) 656{ 657 struct gpio_keys_drvdata *ddata = input_get_drvdata(input); 658 const struct gpio_keys_platform_data *pdata = ddata->pdata; 659 int error; 660 661 if (pdata->enable) { 662 error = pdata->enable(input->dev.parent); 663 if (error) 664 return error; 665 } 666 667 /* Report current state of buttons that are connected to GPIOs */ 668 gpio_keys_report_state(ddata); 669 670 return 0; 671} 672 673static void gpio_keys_close(struct input_dev *input) 674{ 675 struct gpio_keys_drvdata *ddata = input_get_drvdata(input); 676 const struct gpio_keys_platform_data *pdata = ddata->pdata; 677 678 if (pdata->disable) 679 pdata->disable(input->dev.parent); 680} 681 682/* 683 * Handlers for alternative sources of platform_data 684 */ 685 686/* 687 * Translate properties into platform_data 688 */ 689static struct gpio_keys_platform_data * 690gpio_keys_get_devtree_pdata(struct device *dev) 691{ 692 struct gpio_keys_platform_data *pdata; 693 struct gpio_keys_button *button; 694 struct fwnode_handle *child; 695 int nbuttons; 696 697 nbuttons = device_get_child_node_count(dev); 698 if (nbuttons == 0) 699 return ERR_PTR(-ENODEV); 700 701 pdata = devm_kzalloc(dev, 702 sizeof(*pdata) + nbuttons * sizeof(*button), 703 GFP_KERNEL); 704 if (!pdata) 705 return ERR_PTR(-ENOMEM); 706 707 button = (struct gpio_keys_button *)(pdata + 1); 708 709 pdata->buttons = button; 710 pdata->nbuttons = nbuttons; 711 712 pdata->rep = device_property_read_bool(dev, "autorepeat"); 713 714 device_property_read_string(dev, "label", &pdata->name); 715 716 device_for_each_child_node(dev, child) { 717 if (is_of_node(child)) 718 button->irq = 719 irq_of_parse_and_map(to_of_node(child), 0); 720 721 if (fwnode_property_read_u32(child, "linux,code", 722 &button->code)) { 723 dev_err(dev, "Button without keycode\n"); 724 fwnode_handle_put(child); 725 return ERR_PTR(-EINVAL); 726 } 727 728 fwnode_property_read_string(child, "label", &button->desc); 729 730 if (fwnode_property_read_u32(child, "linux,input-type", 731 &button->type)) 732 button->type = EV_KEY; 733 734 button->wakeup = 735 fwnode_property_read_bool(child, "wakeup-source") || 736 /* legacy name */ 737 fwnode_property_read_bool(child, "gpio-key,wakeup"); 738 739 fwnode_property_read_u32(child, "wakeup-event-action", 740 &button->wakeup_event_action); 741 742 button->can_disable = 743 fwnode_property_read_bool(child, "linux,can-disable"); 744 745 if (fwnode_property_read_u32(child, "debounce-interval", 746 &button->debounce_interval)) 747 button->debounce_interval = 5; 748 749 button++; 750 } 751 752 return pdata; 753} 754 755static const struct of_device_id gpio_keys_of_match[] = { 756 { .compatible = "gpio-keys", }, 757 { }, 758}; 759MODULE_DEVICE_TABLE(of, gpio_keys_of_match); 760 761static int gpio_keys_probe(struct platform_device *pdev) 762{ 763 struct device *dev = &pdev->dev; 764 const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev); 765 struct fwnode_handle *child = NULL; 766 struct gpio_keys_drvdata *ddata; 767 struct input_dev *input; 768 int i, error; 769 int wakeup = 0; 770 771 if (!pdata) { 772 pdata = gpio_keys_get_devtree_pdata(dev); 773 if (IS_ERR(pdata)) 774 return PTR_ERR(pdata); 775 } 776 777 ddata = devm_kzalloc(dev, struct_size(ddata, data, pdata->nbuttons), 778 GFP_KERNEL); 779 if (!ddata) { 780 dev_err(dev, "failed to allocate state\n"); 781 return -ENOMEM; 782 } 783 784 ddata->keymap = devm_kcalloc(dev, 785 pdata->nbuttons, sizeof(ddata->keymap[0]), 786 GFP_KERNEL); 787 if (!ddata->keymap) 788 return -ENOMEM; 789 790 input = devm_input_allocate_device(dev); 791 if (!input) { 792 dev_err(dev, "failed to allocate input device\n"); 793 return -ENOMEM; 794 } 795 796 ddata->pdata = pdata; 797 ddata->input = input; 798 mutex_init(&ddata->disable_lock); 799 800 platform_set_drvdata(pdev, ddata); 801 input_set_drvdata(input, ddata); 802 803 input->name = pdata->name ? : pdev->name; 804 input->phys = "gpio-keys/input0"; 805 input->dev.parent = dev; 806 input->open = gpio_keys_open; 807 input->close = gpio_keys_close; 808 809 input->id.bustype = BUS_HOST; 810 input->id.vendor = 0x0001; 811 input->id.product = 0x0001; 812 input->id.version = 0x0100; 813 814 input->keycode = ddata->keymap; 815 input->keycodesize = sizeof(ddata->keymap[0]); 816 input->keycodemax = pdata->nbuttons; 817 818 /* Enable auto repeat feature of Linux input subsystem */ 819 if (pdata->rep) 820 __set_bit(EV_REP, input->evbit); 821 822 for (i = 0; i < pdata->nbuttons; i++) { 823 const struct gpio_keys_button *button = &pdata->buttons[i]; 824 825 if (!dev_get_platdata(dev)) { 826 child = device_get_next_child_node(dev, child); 827 if (!child) { 828 dev_err(dev, 829 "missing child device node for entry %d\n", 830 i); 831 return -EINVAL; 832 } 833 } 834 835 error = gpio_keys_setup_key(pdev, input, ddata, 836 button, i, child); 837 if (error) { 838 fwnode_handle_put(child); 839 return error; 840 } 841 842 if (button->wakeup) 843 wakeup = 1; 844 } 845 846 fwnode_handle_put(child); 847 848 error = input_register_device(input); 849 if (error) { 850 dev_err(dev, "Unable to register input device, error: %d\n", 851 error); 852 return error; 853 } 854 855 device_init_wakeup(dev, wakeup); 856 857 return 0; 858} 859 860static int __maybe_unused 861gpio_keys_button_enable_wakeup(struct gpio_button_data *bdata) 862{ 863 int error; 864 865 error = enable_irq_wake(bdata->irq); 866 if (error) { 867 dev_err(bdata->input->dev.parent, 868 "failed to configure IRQ %d as wakeup source: %d\n", 869 bdata->irq, error); 870 return error; 871 } 872 873 if (bdata->wakeup_trigger_type) { 874 error = irq_set_irq_type(bdata->irq, 875 bdata->wakeup_trigger_type); 876 if (error) { 877 dev_err(bdata->input->dev.parent, 878 "failed to set wakeup trigger %08x for IRQ %d: %d\n", 879 bdata->wakeup_trigger_type, bdata->irq, error); 880 disable_irq_wake(bdata->irq); 881 return error; 882 } 883 } 884 885 return 0; 886} 887 888static void __maybe_unused 889gpio_keys_button_disable_wakeup(struct gpio_button_data *bdata) 890{ 891 int error; 892 893 /* 894 * The trigger type is always both edges for gpio-based keys and we do 895 * not support changing wakeup trigger for interrupt-based keys. 896 */ 897 if (bdata->wakeup_trigger_type) { 898 error = irq_set_irq_type(bdata->irq, IRQ_TYPE_EDGE_BOTH); 899 if (error) 900 dev_warn(bdata->input->dev.parent, 901 "failed to restore interrupt trigger for IRQ %d: %d\n", 902 bdata->irq, error); 903 } 904 905 error = disable_irq_wake(bdata->irq); 906 if (error) 907 dev_warn(bdata->input->dev.parent, 908 "failed to disable IRQ %d as wake source: %d\n", 909 bdata->irq, error); 910} 911 912static int __maybe_unused 913gpio_keys_enable_wakeup(struct gpio_keys_drvdata *ddata) 914{ 915 struct gpio_button_data *bdata; 916 int error; 917 int i; 918 919 for (i = 0; i < ddata->pdata->nbuttons; i++) { 920 bdata = &ddata->data[i]; 921 if (bdata->button->wakeup) { 922 error = gpio_keys_button_enable_wakeup(bdata); 923 if (error) 924 goto err_out; 925 } 926 bdata->suspended = true; 927 } 928 929 return 0; 930 931err_out: 932 while (i--) { 933 bdata = &ddata->data[i]; 934 if (bdata->button->wakeup) 935 gpio_keys_button_disable_wakeup(bdata); 936 bdata->suspended = false; 937 } 938 939 return error; 940} 941 942static void __maybe_unused 943gpio_keys_disable_wakeup(struct gpio_keys_drvdata *ddata) 944{ 945 struct gpio_button_data *bdata; 946 int i; 947 948 for (i = 0; i < ddata->pdata->nbuttons; i++) { 949 bdata = &ddata->data[i]; 950 bdata->suspended = false; 951 if (irqd_is_wakeup_set(irq_get_irq_data(bdata->irq))) 952 gpio_keys_button_disable_wakeup(bdata); 953 } 954} 955 956static int __maybe_unused gpio_keys_suspend(struct device *dev) 957{ 958 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); 959 struct input_dev *input = ddata->input; 960 int error; 961 962 if (device_may_wakeup(dev)) { 963 error = gpio_keys_enable_wakeup(ddata); 964 if (error) 965 return error; 966 } else { 967 mutex_lock(&input->mutex); 968 if (input->users) 969 gpio_keys_close(input); 970 mutex_unlock(&input->mutex); 971 } 972 973 return 0; 974} 975 976static int __maybe_unused gpio_keys_resume(struct device *dev) 977{ 978 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); 979 struct input_dev *input = ddata->input; 980 int error = 0; 981 982 if (device_may_wakeup(dev)) { 983 gpio_keys_disable_wakeup(ddata); 984 } else { 985 mutex_lock(&input->mutex); 986 if (input->users) 987 error = gpio_keys_open(input); 988 mutex_unlock(&input->mutex); 989 } 990 991 if (error) 992 return error; 993 994 gpio_keys_report_state(ddata); 995 return 0; 996} 997 998static SIMPLE_DEV_PM_OPS(gpio_keys_pm_ops, gpio_keys_suspend, gpio_keys_resume); 999 1000static void gpio_keys_shutdown(struct platform_device *pdev) 1001{ 1002 int ret; 1003 1004 ret = gpio_keys_suspend(&pdev->dev); 1005 if (ret) 1006 dev_err(&pdev->dev, "failed to shutdown\n"); 1007} 1008 1009static struct platform_driver gpio_keys_device_driver = { 1010 .probe = gpio_keys_probe, 1011 .shutdown = gpio_keys_shutdown, 1012 .driver = { 1013 .name = "gpio-keys", 1014 .pm = &gpio_keys_pm_ops, 1015 .of_match_table = gpio_keys_of_match, 1016 .dev_groups = gpio_keys_groups, 1017 } 1018}; 1019 1020static int __init gpio_keys_init(void) 1021{ 1022 return platform_driver_register(&gpio_keys_device_driver); 1023} 1024 1025static void __exit gpio_keys_exit(void) 1026{ 1027 platform_driver_unregister(&gpio_keys_device_driver); 1028} 1029 1030late_initcall(gpio_keys_init); 1031module_exit(gpio_keys_exit); 1032 1033MODULE_LICENSE("GPL"); 1034MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>"); 1035MODULE_DESCRIPTION("Keyboard driver for GPIOs"); 1036MODULE_ALIAS("platform:gpio-keys"); 1037