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 32 struct 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 53 struct 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[0]; 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 */ 102 static 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 */ 117 static 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 */ 138 static 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 */ 165 static 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 */ 187 static 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 */ 231 static 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); 282 283 out: 284 bitmap_free(bits); 285 return error; 286 } 287 288 #define ATTR_SHOW_FN(name, type, only_disabled) \ 289 static 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 } 299 300 ATTR_SHOW_FN(keys, EV_KEY, false); 301 ATTR_SHOW_FN(switches, EV_SW, false); 302 ATTR_SHOW_FN(disabled_keys, EV_KEY, true); 303 ATTR_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 */ 311 static DEVICE_ATTR(keys, S_IRUGO, gpio_keys_show_keys, NULL); 312 static DEVICE_ATTR(switches, S_IRUGO, gpio_keys_show_switches, NULL); 313 314 #define ATTR_STORE_FN(name, type) \ 315 static 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 } 330 331 ATTR_STORE_FN(disabled_keys, EV_KEY); 332 ATTR_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 */ 340 static DEVICE_ATTR(disabled_keys, S_IWUSR | S_IRUGO, 341 gpio_keys_show_disabled_keys, 342 gpio_keys_store_disabled_keys); 343 static DEVICE_ATTR(disabled_switches, S_IWUSR | S_IRUGO, 344 gpio_keys_show_disabled_switches, 345 gpio_keys_store_disabled_switches); 346 347 static 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 }; 354 355 static const struct attribute_group gpio_keys_attr_group = { 356 .attrs = gpio_keys_attrs, 357 }; 358 359 static void gpio_keys_gpio_report_event(struct gpio_button_data *bdata) 360 { 361 const struct gpio_keys_button *button = bdata->button; 362 struct input_dev *input = bdata->input; 363 unsigned int type = button->type ?: EV_KEY; 364 int state; 365 366 state = gpiod_get_value_cansleep(bdata->gpiod); 367 if (state < 0) { 368 dev_err(input->dev.parent, 369 "failed to get gpio state: %d\n", state); 370 return; 371 } 372 373 if (type == EV_ABS) { 374 if (state) 375 input_event(input, type, button->code, button->value); 376 } else { 377 input_event(input, type, *bdata->code, state); 378 } 379 input_sync(input); 380 } 381 382 static void gpio_keys_gpio_work_func(struct work_struct *work) 383 { 384 struct gpio_button_data *bdata = 385 container_of(work, struct gpio_button_data, work.work); 386 387 gpio_keys_gpio_report_event(bdata); 388 389 if (bdata->button->wakeup) 390 pm_relax(bdata->input->dev.parent); 391 } 392 393 static irqreturn_t gpio_keys_gpio_isr(int irq, void *dev_id) 394 { 395 struct gpio_button_data *bdata = dev_id; 396 397 BUG_ON(irq != bdata->irq); 398 399 if (bdata->button->wakeup) { 400 const struct gpio_keys_button *button = bdata->button; 401 402 pm_stay_awake(bdata->input->dev.parent); 403 if (bdata->suspended && 404 (button->type == 0 || button->type == EV_KEY)) { 405 /* 406 * Simulate wakeup key press in case the key has 407 * already released by the time we got interrupt 408 * handler to run. 409 */ 410 input_report_key(bdata->input, button->code, 1); 411 } 412 } 413 414 mod_delayed_work(system_wq, 415 &bdata->work, 416 msecs_to_jiffies(bdata->software_debounce)); 417 418 return IRQ_HANDLED; 419 } 420 421 static void gpio_keys_irq_timer(struct timer_list *t) 422 { 423 struct gpio_button_data *bdata = from_timer(bdata, t, release_timer); 424 struct input_dev *input = bdata->input; 425 unsigned long flags; 426 427 spin_lock_irqsave(&bdata->lock, flags); 428 if (bdata->key_pressed) { 429 input_event(input, EV_KEY, *bdata->code, 0); 430 input_sync(input); 431 bdata->key_pressed = false; 432 } 433 spin_unlock_irqrestore(&bdata->lock, flags); 434 } 435 436 static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id) 437 { 438 struct gpio_button_data *bdata = dev_id; 439 struct input_dev *input = bdata->input; 440 unsigned long flags; 441 442 BUG_ON(irq != bdata->irq); 443 444 spin_lock_irqsave(&bdata->lock, flags); 445 446 if (!bdata->key_pressed) { 447 if (bdata->button->wakeup) 448 pm_wakeup_event(bdata->input->dev.parent, 0); 449 450 input_event(input, EV_KEY, *bdata->code, 1); 451 input_sync(input); 452 453 if (!bdata->release_delay) { 454 input_event(input, EV_KEY, *bdata->code, 0); 455 input_sync(input); 456 goto out; 457 } 458 459 bdata->key_pressed = true; 460 } 461 462 if (bdata->release_delay) 463 mod_timer(&bdata->release_timer, 464 jiffies + msecs_to_jiffies(bdata->release_delay)); 465 out: 466 spin_unlock_irqrestore(&bdata->lock, flags); 467 return IRQ_HANDLED; 468 } 469 470 static void gpio_keys_quiesce_key(void *data) 471 { 472 struct gpio_button_data *bdata = data; 473 474 if (bdata->gpiod) 475 cancel_delayed_work_sync(&bdata->work); 476 else 477 del_timer_sync(&bdata->release_timer); 478 } 479 480 static int gpio_keys_setup_key(struct platform_device *pdev, 481 struct input_dev *input, 482 struct gpio_keys_drvdata *ddata, 483 const struct gpio_keys_button *button, 484 int idx, 485 struct fwnode_handle *child) 486 { 487 const char *desc = button->desc ? button->desc : "gpio_keys"; 488 struct device *dev = &pdev->dev; 489 struct gpio_button_data *bdata = &ddata->data[idx]; 490 irq_handler_t isr; 491 unsigned long irqflags; 492 int irq; 493 int error; 494 495 bdata->input = input; 496 bdata->button = button; 497 spin_lock_init(&bdata->lock); 498 499 if (child) { 500 bdata->gpiod = devm_fwnode_get_gpiod_from_child(dev, NULL, 501 child, 502 GPIOD_IN, 503 desc); 504 if (IS_ERR(bdata->gpiod)) { 505 error = PTR_ERR(bdata->gpiod); 506 if (error == -ENOENT) { 507 /* 508 * GPIO is optional, we may be dealing with 509 * purely interrupt-driven setup. 510 */ 511 bdata->gpiod = NULL; 512 } else { 513 if (error != -EPROBE_DEFER) 514 dev_err(dev, "failed to get gpio: %d\n", 515 error); 516 return error; 517 } 518 } 519 } else if (gpio_is_valid(button->gpio)) { 520 /* 521 * Legacy GPIO number, so request the GPIO here and 522 * convert it to descriptor. 523 */ 524 unsigned flags = GPIOF_IN; 525 526 if (button->active_low) 527 flags |= GPIOF_ACTIVE_LOW; 528 529 error = devm_gpio_request_one(dev, button->gpio, flags, desc); 530 if (error < 0) { 531 dev_err(dev, "Failed to request GPIO %d, error %d\n", 532 button->gpio, error); 533 return error; 534 } 535 536 bdata->gpiod = gpio_to_desc(button->gpio); 537 if (!bdata->gpiod) 538 return -EINVAL; 539 } 540 541 if (bdata->gpiod) { 542 bool active_low = gpiod_is_active_low(bdata->gpiod); 543 544 if (button->debounce_interval) { 545 error = gpiod_set_debounce(bdata->gpiod, 546 button->debounce_interval * 1000); 547 /* use timer if gpiolib doesn't provide debounce */ 548 if (error < 0) 549 bdata->software_debounce = 550 button->debounce_interval; 551 } 552 553 if (button->irq) { 554 bdata->irq = button->irq; 555 } else { 556 irq = gpiod_to_irq(bdata->gpiod); 557 if (irq < 0) { 558 error = irq; 559 dev_err(dev, 560 "Unable to get irq number for GPIO %d, error %d\n", 561 button->gpio, error); 562 return error; 563 } 564 bdata->irq = irq; 565 } 566 567 INIT_DELAYED_WORK(&bdata->work, gpio_keys_gpio_work_func); 568 569 isr = gpio_keys_gpio_isr; 570 irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING; 571 572 switch (button->wakeup_event_action) { 573 case EV_ACT_ASSERTED: 574 bdata->wakeup_trigger_type = active_low ? 575 IRQ_TYPE_EDGE_FALLING : IRQ_TYPE_EDGE_RISING; 576 break; 577 case EV_ACT_DEASSERTED: 578 bdata->wakeup_trigger_type = active_low ? 579 IRQ_TYPE_EDGE_RISING : IRQ_TYPE_EDGE_FALLING; 580 break; 581 case EV_ACT_ANY: 582 /* fall through */ 583 default: 584 /* 585 * For other cases, we are OK letting suspend/resume 586 * not reconfigure the trigger type. 587 */ 588 break; 589 } 590 } else { 591 if (!button->irq) { 592 dev_err(dev, "Found button without gpio or irq\n"); 593 return -EINVAL; 594 } 595 596 bdata->irq = button->irq; 597 598 if (button->type && button->type != EV_KEY) { 599 dev_err(dev, "Only EV_KEY allowed for IRQ buttons.\n"); 600 return -EINVAL; 601 } 602 603 bdata->release_delay = button->debounce_interval; 604 timer_setup(&bdata->release_timer, gpio_keys_irq_timer, 0); 605 606 isr = gpio_keys_irq_isr; 607 irqflags = 0; 608 609 /* 610 * For IRQ buttons, there is no interrupt for release. 611 * So we don't need to reconfigure the trigger type for wakeup. 612 */ 613 } 614 615 bdata->code = &ddata->keymap[idx]; 616 *bdata->code = button->code; 617 input_set_capability(input, button->type ?: EV_KEY, *bdata->code); 618 619 /* 620 * Install custom action to cancel release timer and 621 * workqueue item. 622 */ 623 error = devm_add_action(dev, gpio_keys_quiesce_key, bdata); 624 if (error) { 625 dev_err(dev, "failed to register quiesce action, error: %d\n", 626 error); 627 return error; 628 } 629 630 /* 631 * If platform has specified that the button can be disabled, 632 * we don't want it to share the interrupt line. 633 */ 634 if (!button->can_disable) 635 irqflags |= IRQF_SHARED; 636 637 error = devm_request_any_context_irq(dev, bdata->irq, isr, irqflags, 638 desc, bdata); 639 if (error < 0) { 640 dev_err(dev, "Unable to claim irq %d; error %d\n", 641 bdata->irq, error); 642 return error; 643 } 644 645 return 0; 646 } 647 648 static void gpio_keys_report_state(struct gpio_keys_drvdata *ddata) 649 { 650 struct input_dev *input = ddata->input; 651 int i; 652 653 for (i = 0; i < ddata->pdata->nbuttons; i++) { 654 struct gpio_button_data *bdata = &ddata->data[i]; 655 if (bdata->gpiod) 656 gpio_keys_gpio_report_event(bdata); 657 } 658 input_sync(input); 659 } 660 661 static int gpio_keys_open(struct input_dev *input) 662 { 663 struct gpio_keys_drvdata *ddata = input_get_drvdata(input); 664 const struct gpio_keys_platform_data *pdata = ddata->pdata; 665 int error; 666 667 if (pdata->enable) { 668 error = pdata->enable(input->dev.parent); 669 if (error) 670 return error; 671 } 672 673 /* Report current state of buttons that are connected to GPIOs */ 674 gpio_keys_report_state(ddata); 675 676 return 0; 677 } 678 679 static void gpio_keys_close(struct input_dev *input) 680 { 681 struct gpio_keys_drvdata *ddata = input_get_drvdata(input); 682 const struct gpio_keys_platform_data *pdata = ddata->pdata; 683 684 if (pdata->disable) 685 pdata->disable(input->dev.parent); 686 } 687 688 /* 689 * Handlers for alternative sources of platform_data 690 */ 691 692 /* 693 * Translate properties into platform_data 694 */ 695 static struct gpio_keys_platform_data * 696 gpio_keys_get_devtree_pdata(struct device *dev) 697 { 698 struct gpio_keys_platform_data *pdata; 699 struct gpio_keys_button *button; 700 struct fwnode_handle *child; 701 int nbuttons; 702 703 nbuttons = device_get_child_node_count(dev); 704 if (nbuttons == 0) 705 return ERR_PTR(-ENODEV); 706 707 pdata = devm_kzalloc(dev, 708 sizeof(*pdata) + nbuttons * sizeof(*button), 709 GFP_KERNEL); 710 if (!pdata) 711 return ERR_PTR(-ENOMEM); 712 713 button = (struct gpio_keys_button *)(pdata + 1); 714 715 pdata->buttons = button; 716 pdata->nbuttons = nbuttons; 717 718 pdata->rep = device_property_read_bool(dev, "autorepeat"); 719 720 device_property_read_string(dev, "label", &pdata->name); 721 722 device_for_each_child_node(dev, child) { 723 if (is_of_node(child)) 724 button->irq = 725 irq_of_parse_and_map(to_of_node(child), 0); 726 727 if (fwnode_property_read_u32(child, "linux,code", 728 &button->code)) { 729 dev_err(dev, "Button without keycode\n"); 730 fwnode_handle_put(child); 731 return ERR_PTR(-EINVAL); 732 } 733 734 fwnode_property_read_string(child, "label", &button->desc); 735 736 if (fwnode_property_read_u32(child, "linux,input-type", 737 &button->type)) 738 button->type = EV_KEY; 739 740 button->wakeup = 741 fwnode_property_read_bool(child, "wakeup-source") || 742 /* legacy name */ 743 fwnode_property_read_bool(child, "gpio-key,wakeup"); 744 745 fwnode_property_read_u32(child, "wakeup-event-action", 746 &button->wakeup_event_action); 747 748 button->can_disable = 749 fwnode_property_read_bool(child, "linux,can-disable"); 750 751 if (fwnode_property_read_u32(child, "debounce-interval", 752 &button->debounce_interval)) 753 button->debounce_interval = 5; 754 755 button++; 756 } 757 758 return pdata; 759 } 760 761 static const struct of_device_id gpio_keys_of_match[] = { 762 { .compatible = "gpio-keys", }, 763 { }, 764 }; 765 MODULE_DEVICE_TABLE(of, gpio_keys_of_match); 766 767 static int gpio_keys_probe(struct platform_device *pdev) 768 { 769 struct device *dev = &pdev->dev; 770 const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev); 771 struct fwnode_handle *child = NULL; 772 struct gpio_keys_drvdata *ddata; 773 struct input_dev *input; 774 int i, error; 775 int wakeup = 0; 776 777 if (!pdata) { 778 pdata = gpio_keys_get_devtree_pdata(dev); 779 if (IS_ERR(pdata)) 780 return PTR_ERR(pdata); 781 } 782 783 ddata = devm_kzalloc(dev, struct_size(ddata, data, pdata->nbuttons), 784 GFP_KERNEL); 785 if (!ddata) { 786 dev_err(dev, "failed to allocate state\n"); 787 return -ENOMEM; 788 } 789 790 ddata->keymap = devm_kcalloc(dev, 791 pdata->nbuttons, sizeof(ddata->keymap[0]), 792 GFP_KERNEL); 793 if (!ddata->keymap) 794 return -ENOMEM; 795 796 input = devm_input_allocate_device(dev); 797 if (!input) { 798 dev_err(dev, "failed to allocate input device\n"); 799 return -ENOMEM; 800 } 801 802 ddata->pdata = pdata; 803 ddata->input = input; 804 mutex_init(&ddata->disable_lock); 805 806 platform_set_drvdata(pdev, ddata); 807 input_set_drvdata(input, ddata); 808 809 input->name = pdata->name ? : pdev->name; 810 input->phys = "gpio-keys/input0"; 811 input->dev.parent = dev; 812 input->open = gpio_keys_open; 813 input->close = gpio_keys_close; 814 815 input->id.bustype = BUS_HOST; 816 input->id.vendor = 0x0001; 817 input->id.product = 0x0001; 818 input->id.version = 0x0100; 819 820 input->keycode = ddata->keymap; 821 input->keycodesize = sizeof(ddata->keymap[0]); 822 input->keycodemax = pdata->nbuttons; 823 824 /* Enable auto repeat feature of Linux input subsystem */ 825 if (pdata->rep) 826 __set_bit(EV_REP, input->evbit); 827 828 for (i = 0; i < pdata->nbuttons; i++) { 829 const struct gpio_keys_button *button = &pdata->buttons[i]; 830 831 if (!dev_get_platdata(dev)) { 832 child = device_get_next_child_node(dev, child); 833 if (!child) { 834 dev_err(dev, 835 "missing child device node for entry %d\n", 836 i); 837 return -EINVAL; 838 } 839 } 840 841 error = gpio_keys_setup_key(pdev, input, ddata, 842 button, i, child); 843 if (error) { 844 fwnode_handle_put(child); 845 return error; 846 } 847 848 if (button->wakeup) 849 wakeup = 1; 850 } 851 852 fwnode_handle_put(child); 853 854 error = devm_device_add_group(dev, &gpio_keys_attr_group); 855 if (error) { 856 dev_err(dev, "Unable to export keys/switches, error: %d\n", 857 error); 858 return error; 859 } 860 861 error = input_register_device(input); 862 if (error) { 863 dev_err(dev, "Unable to register input device, error: %d\n", 864 error); 865 return error; 866 } 867 868 device_init_wakeup(dev, wakeup); 869 870 return 0; 871 } 872 873 static int __maybe_unused 874 gpio_keys_button_enable_wakeup(struct gpio_button_data *bdata) 875 { 876 int error; 877 878 error = enable_irq_wake(bdata->irq); 879 if (error) { 880 dev_err(bdata->input->dev.parent, 881 "failed to configure IRQ %d as wakeup source: %d\n", 882 bdata->irq, error); 883 return error; 884 } 885 886 if (bdata->wakeup_trigger_type) { 887 error = irq_set_irq_type(bdata->irq, 888 bdata->wakeup_trigger_type); 889 if (error) { 890 dev_err(bdata->input->dev.parent, 891 "failed to set wakeup trigger %08x for IRQ %d: %d\n", 892 bdata->wakeup_trigger_type, bdata->irq, error); 893 disable_irq_wake(bdata->irq); 894 return error; 895 } 896 } 897 898 return 0; 899 } 900 901 static void __maybe_unused 902 gpio_keys_button_disable_wakeup(struct gpio_button_data *bdata) 903 { 904 int error; 905 906 /* 907 * The trigger type is always both edges for gpio-based keys and we do 908 * not support changing wakeup trigger for interrupt-based keys. 909 */ 910 if (bdata->wakeup_trigger_type) { 911 error = irq_set_irq_type(bdata->irq, IRQ_TYPE_EDGE_BOTH); 912 if (error) 913 dev_warn(bdata->input->dev.parent, 914 "failed to restore interrupt trigger for IRQ %d: %d\n", 915 bdata->irq, error); 916 } 917 918 error = disable_irq_wake(bdata->irq); 919 if (error) 920 dev_warn(bdata->input->dev.parent, 921 "failed to disable IRQ %d as wake source: %d\n", 922 bdata->irq, error); 923 } 924 925 static int __maybe_unused 926 gpio_keys_enable_wakeup(struct gpio_keys_drvdata *ddata) 927 { 928 struct gpio_button_data *bdata; 929 int error; 930 int i; 931 932 for (i = 0; i < ddata->pdata->nbuttons; i++) { 933 bdata = &ddata->data[i]; 934 if (bdata->button->wakeup) { 935 error = gpio_keys_button_enable_wakeup(bdata); 936 if (error) 937 goto err_out; 938 } 939 bdata->suspended = true; 940 } 941 942 return 0; 943 944 err_out: 945 while (i--) { 946 bdata = &ddata->data[i]; 947 if (bdata->button->wakeup) 948 gpio_keys_button_disable_wakeup(bdata); 949 bdata->suspended = false; 950 } 951 952 return error; 953 } 954 955 static void __maybe_unused 956 gpio_keys_disable_wakeup(struct gpio_keys_drvdata *ddata) 957 { 958 struct gpio_button_data *bdata; 959 int i; 960 961 for (i = 0; i < ddata->pdata->nbuttons; i++) { 962 bdata = &ddata->data[i]; 963 bdata->suspended = false; 964 if (irqd_is_wakeup_set(irq_get_irq_data(bdata->irq))) 965 gpio_keys_button_disable_wakeup(bdata); 966 } 967 } 968 969 static int __maybe_unused gpio_keys_suspend(struct device *dev) 970 { 971 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); 972 struct input_dev *input = ddata->input; 973 int error; 974 975 if (device_may_wakeup(dev)) { 976 error = gpio_keys_enable_wakeup(ddata); 977 if (error) 978 return error; 979 } else { 980 mutex_lock(&input->mutex); 981 if (input->users) 982 gpio_keys_close(input); 983 mutex_unlock(&input->mutex); 984 } 985 986 return 0; 987 } 988 989 static int __maybe_unused gpio_keys_resume(struct device *dev) 990 { 991 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); 992 struct input_dev *input = ddata->input; 993 int error = 0; 994 995 if (device_may_wakeup(dev)) { 996 gpio_keys_disable_wakeup(ddata); 997 } else { 998 mutex_lock(&input->mutex); 999 if (input->users) 1000 error = gpio_keys_open(input); 1001 mutex_unlock(&input->mutex); 1002 } 1003 1004 if (error) 1005 return error; 1006 1007 gpio_keys_report_state(ddata); 1008 return 0; 1009 } 1010 1011 static SIMPLE_DEV_PM_OPS(gpio_keys_pm_ops, gpio_keys_suspend, gpio_keys_resume); 1012 1013 static void gpio_keys_shutdown(struct platform_device *pdev) 1014 { 1015 int ret; 1016 1017 ret = gpio_keys_suspend(&pdev->dev); 1018 if (ret) 1019 dev_err(&pdev->dev, "failed to shutdown\n"); 1020 } 1021 1022 static struct platform_driver gpio_keys_device_driver = { 1023 .probe = gpio_keys_probe, 1024 .shutdown = gpio_keys_shutdown, 1025 .driver = { 1026 .name = "gpio-keys", 1027 .pm = &gpio_keys_pm_ops, 1028 .of_match_table = gpio_keys_of_match, 1029 } 1030 }; 1031 1032 static int __init gpio_keys_init(void) 1033 { 1034 return platform_driver_register(&gpio_keys_device_driver); 1035 } 1036 1037 static void __exit gpio_keys_exit(void) 1038 { 1039 platform_driver_unregister(&gpio_keys_device_driver); 1040 } 1041 1042 late_initcall(gpio_keys_init); 1043 module_exit(gpio_keys_exit); 1044 1045 MODULE_LICENSE("GPL"); 1046 MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>"); 1047 MODULE_DESCRIPTION("Keyboard driver for GPIOs"); 1048 MODULE_ALIAS("platform:gpio-keys"); 1049