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/hrtimer.h> 12 #include <linux/init.h> 13 #include <linux/fs.h> 14 #include <linux/interrupt.h> 15 #include <linux/irq.h> 16 #include <linux/sched.h> 17 #include <linux/pm.h> 18 #include <linux/slab.h> 19 #include <linux/sysctl.h> 20 #include <linux/proc_fs.h> 21 #include <linux/delay.h> 22 #include <linux/platform_device.h> 23 #include <linux/input.h> 24 #include <linux/gpio_keys.h> 25 #include <linux/workqueue.h> 26 #include <linux/gpio.h> 27 #include <linux/gpio/consumer.h> 28 #include <linux/of.h> 29 #include <linux/of_irq.h> 30 #include <linux/spinlock.h> 31 #include <dt-bindings/input/gpio-keys.h> 32 33 struct gpio_button_data { 34 const struct gpio_keys_button *button; 35 struct input_dev *input; 36 struct gpio_desc *gpiod; 37 38 unsigned short *code; 39 40 struct hrtimer release_timer; 41 unsigned int release_delay; /* in msecs, for IRQ-only buttons */ 42 43 struct delayed_work work; 44 struct hrtimer debounce_timer; 45 unsigned int software_debounce; /* in msecs, for GPIO-driven buttons */ 46 47 unsigned int irq; 48 unsigned int wakeup_trigger_type; 49 spinlock_t lock; 50 bool disabled; 51 bool key_pressed; 52 bool suspended; 53 bool debounce_use_hrtimer; 54 }; 55 56 struct gpio_keys_drvdata { 57 const struct gpio_keys_platform_data *pdata; 58 struct input_dev *input; 59 struct mutex disable_lock; 60 unsigned short *keymap; 61 struct gpio_button_data data[]; 62 }; 63 64 /* 65 * SYSFS interface for enabling/disabling keys and switches: 66 * 67 * There are 4 attributes under /sys/devices/platform/gpio-keys/ 68 * keys [ro] - bitmap of keys (EV_KEY) which can be 69 * disabled 70 * switches [ro] - bitmap of switches (EV_SW) which can be 71 * disabled 72 * disabled_keys [rw] - bitmap of keys currently disabled 73 * disabled_switches [rw] - bitmap of switches currently disabled 74 * 75 * Userland can change these values and hence disable event generation 76 * for each key (or switch). Disabling a key means its interrupt line 77 * is disabled. 78 * 79 * For example, if we have following switches set up as gpio-keys: 80 * SW_DOCK = 5 81 * SW_CAMERA_LENS_COVER = 9 82 * SW_KEYPAD_SLIDE = 10 83 * SW_FRONT_PROXIMITY = 11 84 * This is read from switches: 85 * 11-9,5 86 * Next we want to disable proximity (11) and dock (5), we write: 87 * 11,5 88 * to file disabled_switches. Now proximity and dock IRQs are disabled. 89 * This can be verified by reading the file disabled_switches: 90 * 11,5 91 * If we now want to enable proximity (11) switch we write: 92 * 5 93 * to disabled_switches. 94 * 95 * We can disable only those keys which don't allow sharing the irq. 96 */ 97 98 /** 99 * get_n_events_by_type() - returns maximum number of events per @type 100 * @type: type of button (%EV_KEY, %EV_SW) 101 * 102 * Return value of this function can be used to allocate bitmap 103 * large enough to hold all bits for given type. 104 */ 105 static int get_n_events_by_type(int type) 106 { 107 BUG_ON(type != EV_SW && type != EV_KEY); 108 109 return (type == EV_KEY) ? KEY_CNT : SW_CNT; 110 } 111 112 /** 113 * get_bm_events_by_type() - returns bitmap of supported events per @type 114 * @dev: input device from which bitmap is retrieved 115 * @type: type of button (%EV_KEY, %EV_SW) 116 * 117 * Return value of this function can be used to allocate bitmap 118 * large enough to hold all bits for given type. 119 */ 120 static const unsigned long *get_bm_events_by_type(struct input_dev *dev, 121 int type) 122 { 123 BUG_ON(type != EV_SW && type != EV_KEY); 124 125 return (type == EV_KEY) ? dev->keybit : dev->swbit; 126 } 127 128 static void gpio_keys_quiesce_key(void *data) 129 { 130 struct gpio_button_data *bdata = data; 131 132 if (!bdata->gpiod) 133 hrtimer_cancel(&bdata->release_timer); 134 else if (bdata->debounce_use_hrtimer) 135 hrtimer_cancel(&bdata->debounce_timer); 136 else 137 cancel_delayed_work_sync(&bdata->work); 138 } 139 140 /** 141 * gpio_keys_disable_button() - disables given GPIO button 142 * @bdata: button data for button to be disabled 143 * 144 * Disables button pointed by @bdata. This is done by masking 145 * IRQ line. After this function is called, button won't generate 146 * input events anymore. Note that one can only disable buttons 147 * that don't share IRQs. 148 * 149 * Make sure that @bdata->disable_lock is locked when entering 150 * this function to avoid races when concurrent threads are 151 * disabling buttons at the same time. 152 */ 153 static void gpio_keys_disable_button(struct gpio_button_data *bdata) 154 { 155 if (!bdata->disabled) { 156 /* 157 * Disable IRQ and associated timer/work structure. 158 */ 159 disable_irq(bdata->irq); 160 gpio_keys_quiesce_key(bdata); 161 bdata->disabled = true; 162 } 163 } 164 165 /** 166 * gpio_keys_enable_button() - enables given GPIO button 167 * @bdata: button data for button to be disabled 168 * 169 * Enables given button pointed by @bdata. 170 * 171 * Make sure that @bdata->disable_lock is locked when entering 172 * this function to avoid races with concurrent threads trying 173 * to enable the same button at the same time. 174 */ 175 static void gpio_keys_enable_button(struct gpio_button_data *bdata) 176 { 177 if (bdata->disabled) { 178 enable_irq(bdata->irq); 179 bdata->disabled = false; 180 } 181 } 182 183 /** 184 * gpio_keys_attr_show_helper() - fill in stringified bitmap of buttons 185 * @ddata: pointer to drvdata 186 * @buf: buffer where stringified bitmap is written 187 * @type: button type (%EV_KEY, %EV_SW) 188 * @only_disabled: does caller want only those buttons that are 189 * currently disabled or all buttons that can be 190 * disabled 191 * 192 * This function writes buttons that can be disabled to @buf. If 193 * @only_disabled is true, then @buf contains only those buttons 194 * that are currently disabled. Returns 0 on success or negative 195 * errno on failure. 196 */ 197 static ssize_t gpio_keys_attr_show_helper(struct gpio_keys_drvdata *ddata, 198 char *buf, unsigned int type, 199 bool only_disabled) 200 { 201 int n_events = get_n_events_by_type(type); 202 unsigned long *bits; 203 ssize_t ret; 204 int i; 205 206 bits = bitmap_zalloc(n_events, GFP_KERNEL); 207 if (!bits) 208 return -ENOMEM; 209 210 for (i = 0; i < ddata->pdata->nbuttons; i++) { 211 struct gpio_button_data *bdata = &ddata->data[i]; 212 213 if (bdata->button->type != type) 214 continue; 215 216 if (only_disabled && !bdata->disabled) 217 continue; 218 219 __set_bit(*bdata->code, bits); 220 } 221 222 ret = scnprintf(buf, PAGE_SIZE - 1, "%*pbl", n_events, bits); 223 buf[ret++] = '\n'; 224 buf[ret] = '\0'; 225 226 bitmap_free(bits); 227 228 return ret; 229 } 230 231 /** 232 * gpio_keys_attr_store_helper() - enable/disable buttons based on given bitmap 233 * @ddata: pointer to drvdata 234 * @buf: buffer from userspace that contains stringified bitmap 235 * @type: button type (%EV_KEY, %EV_SW) 236 * 237 * This function parses stringified bitmap from @buf and disables/enables 238 * GPIO buttons accordingly. Returns 0 on success and negative error 239 * on failure. 240 */ 241 static ssize_t gpio_keys_attr_store_helper(struct gpio_keys_drvdata *ddata, 242 const char *buf, unsigned int type) 243 { 244 int n_events = get_n_events_by_type(type); 245 const unsigned long *bitmap = get_bm_events_by_type(ddata->input, type); 246 unsigned long *bits; 247 ssize_t error; 248 int i; 249 250 bits = bitmap_alloc(n_events, GFP_KERNEL); 251 if (!bits) 252 return -ENOMEM; 253 254 error = bitmap_parselist(buf, bits, n_events); 255 if (error) 256 goto out; 257 258 /* First validate */ 259 if (!bitmap_subset(bits, bitmap, n_events)) { 260 error = -EINVAL; 261 goto out; 262 } 263 264 for (i = 0; i < ddata->pdata->nbuttons; i++) { 265 struct gpio_button_data *bdata = &ddata->data[i]; 266 267 if (bdata->button->type != type) 268 continue; 269 270 if (test_bit(*bdata->code, bits) && 271 !bdata->button->can_disable) { 272 error = -EINVAL; 273 goto out; 274 } 275 } 276 277 mutex_lock(&ddata->disable_lock); 278 279 for (i = 0; i < ddata->pdata->nbuttons; i++) { 280 struct gpio_button_data *bdata = &ddata->data[i]; 281 282 if (bdata->button->type != type) 283 continue; 284 285 if (test_bit(*bdata->code, bits)) 286 gpio_keys_disable_button(bdata); 287 else 288 gpio_keys_enable_button(bdata); 289 } 290 291 mutex_unlock(&ddata->disable_lock); 292 293 out: 294 bitmap_free(bits); 295 return error; 296 } 297 298 #define ATTR_SHOW_FN(name, type, only_disabled) \ 299 static ssize_t gpio_keys_show_##name(struct device *dev, \ 300 struct device_attribute *attr, \ 301 char *buf) \ 302 { \ 303 struct platform_device *pdev = to_platform_device(dev); \ 304 struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \ 305 \ 306 return gpio_keys_attr_show_helper(ddata, buf, \ 307 type, only_disabled); \ 308 } 309 310 ATTR_SHOW_FN(keys, EV_KEY, false); 311 ATTR_SHOW_FN(switches, EV_SW, false); 312 ATTR_SHOW_FN(disabled_keys, EV_KEY, true); 313 ATTR_SHOW_FN(disabled_switches, EV_SW, true); 314 315 /* 316 * ATTRIBUTES: 317 * 318 * /sys/devices/platform/gpio-keys/keys [ro] 319 * /sys/devices/platform/gpio-keys/switches [ro] 320 */ 321 static DEVICE_ATTR(keys, S_IRUGO, gpio_keys_show_keys, NULL); 322 static DEVICE_ATTR(switches, S_IRUGO, gpio_keys_show_switches, NULL); 323 324 #define ATTR_STORE_FN(name, type) \ 325 static ssize_t gpio_keys_store_##name(struct device *dev, \ 326 struct device_attribute *attr, \ 327 const char *buf, \ 328 size_t count) \ 329 { \ 330 struct platform_device *pdev = to_platform_device(dev); \ 331 struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \ 332 ssize_t error; \ 333 \ 334 error = gpio_keys_attr_store_helper(ddata, buf, type); \ 335 if (error) \ 336 return error; \ 337 \ 338 return count; \ 339 } 340 341 ATTR_STORE_FN(disabled_keys, EV_KEY); 342 ATTR_STORE_FN(disabled_switches, EV_SW); 343 344 /* 345 * ATTRIBUTES: 346 * 347 * /sys/devices/platform/gpio-keys/disabled_keys [rw] 348 * /sys/devices/platform/gpio-keys/disables_switches [rw] 349 */ 350 static DEVICE_ATTR(disabled_keys, S_IWUSR | S_IRUGO, 351 gpio_keys_show_disabled_keys, 352 gpio_keys_store_disabled_keys); 353 static DEVICE_ATTR(disabled_switches, S_IWUSR | S_IRUGO, 354 gpio_keys_show_disabled_switches, 355 gpio_keys_store_disabled_switches); 356 357 static struct attribute *gpio_keys_attrs[] = { 358 &dev_attr_keys.attr, 359 &dev_attr_switches.attr, 360 &dev_attr_disabled_keys.attr, 361 &dev_attr_disabled_switches.attr, 362 NULL, 363 }; 364 ATTRIBUTE_GROUPS(gpio_keys); 365 366 static void gpio_keys_gpio_report_event(struct gpio_button_data *bdata) 367 { 368 const struct gpio_keys_button *button = bdata->button; 369 struct input_dev *input = bdata->input; 370 unsigned int type = button->type ?: EV_KEY; 371 int state; 372 373 state = bdata->debounce_use_hrtimer ? 374 gpiod_get_value(bdata->gpiod) : 375 gpiod_get_value_cansleep(bdata->gpiod); 376 if (state < 0) { 377 dev_err(input->dev.parent, 378 "failed to get gpio state: %d\n", state); 379 return; 380 } 381 382 if (type == EV_ABS) { 383 if (state) 384 input_event(input, type, button->code, button->value); 385 } else { 386 input_event(input, type, *bdata->code, state); 387 } 388 } 389 390 static void gpio_keys_debounce_event(struct gpio_button_data *bdata) 391 { 392 gpio_keys_gpio_report_event(bdata); 393 input_sync(bdata->input); 394 395 if (bdata->button->wakeup) 396 pm_relax(bdata->input->dev.parent); 397 } 398 399 static void gpio_keys_gpio_work_func(struct work_struct *work) 400 { 401 struct gpio_button_data *bdata = 402 container_of(work, struct gpio_button_data, work.work); 403 404 gpio_keys_debounce_event(bdata); 405 } 406 407 static enum hrtimer_restart gpio_keys_debounce_timer(struct hrtimer *t) 408 { 409 struct gpio_button_data *bdata = 410 container_of(t, struct gpio_button_data, debounce_timer); 411 412 gpio_keys_debounce_event(bdata); 413 414 return HRTIMER_NORESTART; 415 } 416 417 static irqreturn_t gpio_keys_gpio_isr(int irq, void *dev_id) 418 { 419 struct gpio_button_data *bdata = dev_id; 420 421 BUG_ON(irq != bdata->irq); 422 423 if (bdata->button->wakeup) { 424 const struct gpio_keys_button *button = bdata->button; 425 426 pm_stay_awake(bdata->input->dev.parent); 427 if (bdata->suspended && 428 (button->type == 0 || button->type == EV_KEY)) { 429 /* 430 * Simulate wakeup key press in case the key has 431 * already released by the time we got interrupt 432 * handler to run. 433 */ 434 input_report_key(bdata->input, button->code, 1); 435 } 436 } 437 438 if (bdata->debounce_use_hrtimer) { 439 hrtimer_start(&bdata->debounce_timer, 440 ms_to_ktime(bdata->software_debounce), 441 HRTIMER_MODE_REL); 442 } else { 443 mod_delayed_work(system_wq, 444 &bdata->work, 445 msecs_to_jiffies(bdata->software_debounce)); 446 } 447 448 return IRQ_HANDLED; 449 } 450 451 static enum hrtimer_restart gpio_keys_irq_timer(struct hrtimer *t) 452 { 453 struct gpio_button_data *bdata = container_of(t, 454 struct gpio_button_data, 455 release_timer); 456 struct input_dev *input = bdata->input; 457 458 if (bdata->key_pressed) { 459 input_report_key(input, *bdata->code, 0); 460 input_sync(input); 461 bdata->key_pressed = false; 462 } 463 464 return HRTIMER_NORESTART; 465 } 466 467 static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id) 468 { 469 struct gpio_button_data *bdata = dev_id; 470 struct input_dev *input = bdata->input; 471 unsigned long flags; 472 473 BUG_ON(irq != bdata->irq); 474 475 spin_lock_irqsave(&bdata->lock, flags); 476 477 if (!bdata->key_pressed) { 478 if (bdata->button->wakeup) 479 pm_wakeup_event(bdata->input->dev.parent, 0); 480 481 input_report_key(input, *bdata->code, 1); 482 input_sync(input); 483 484 if (!bdata->release_delay) { 485 input_report_key(input, *bdata->code, 0); 486 input_sync(input); 487 goto out; 488 } 489 490 bdata->key_pressed = true; 491 } 492 493 if (bdata->release_delay) 494 hrtimer_start(&bdata->release_timer, 495 ms_to_ktime(bdata->release_delay), 496 HRTIMER_MODE_REL_HARD); 497 out: 498 spin_unlock_irqrestore(&bdata->lock, flags); 499 return IRQ_HANDLED; 500 } 501 502 static int gpio_keys_setup_key(struct platform_device *pdev, 503 struct input_dev *input, 504 struct gpio_keys_drvdata *ddata, 505 const struct gpio_keys_button *button, 506 int idx, 507 struct fwnode_handle *child) 508 { 509 const char *desc = button->desc ? button->desc : "gpio_keys"; 510 struct device *dev = &pdev->dev; 511 struct gpio_button_data *bdata = &ddata->data[idx]; 512 irq_handler_t isr; 513 unsigned long irqflags; 514 int irq; 515 int error; 516 517 bdata->input = input; 518 bdata->button = button; 519 spin_lock_init(&bdata->lock); 520 521 if (child) { 522 bdata->gpiod = devm_fwnode_gpiod_get(dev, child, 523 NULL, GPIOD_IN, desc); 524 if (IS_ERR(bdata->gpiod)) { 525 error = PTR_ERR(bdata->gpiod); 526 if (error == -ENOENT) { 527 /* 528 * GPIO is optional, we may be dealing with 529 * purely interrupt-driven setup. 530 */ 531 bdata->gpiod = NULL; 532 } else { 533 if (error != -EPROBE_DEFER) 534 dev_err(dev, "failed to get gpio: %d\n", 535 error); 536 return error; 537 } 538 } 539 } else if (gpio_is_valid(button->gpio)) { 540 /* 541 * Legacy GPIO number, so request the GPIO here and 542 * convert it to descriptor. 543 */ 544 unsigned flags = GPIOF_IN; 545 546 if (button->active_low) 547 flags |= GPIOF_ACTIVE_LOW; 548 549 error = devm_gpio_request_one(dev, button->gpio, flags, desc); 550 if (error < 0) { 551 dev_err(dev, "Failed to request GPIO %d, error %d\n", 552 button->gpio, error); 553 return error; 554 } 555 556 bdata->gpiod = gpio_to_desc(button->gpio); 557 if (!bdata->gpiod) 558 return -EINVAL; 559 } 560 561 if (bdata->gpiod) { 562 bool active_low = gpiod_is_active_low(bdata->gpiod); 563 564 if (button->debounce_interval) { 565 error = gpiod_set_debounce(bdata->gpiod, 566 button->debounce_interval * 1000); 567 /* use timer if gpiolib doesn't provide debounce */ 568 if (error < 0) 569 bdata->software_debounce = 570 button->debounce_interval; 571 572 /* 573 * If reading the GPIO won't sleep, we can use a 574 * hrtimer instead of a standard timer for the software 575 * debounce, to reduce the latency as much as possible. 576 */ 577 bdata->debounce_use_hrtimer = 578 !gpiod_cansleep(bdata->gpiod); 579 } 580 581 if (button->irq) { 582 bdata->irq = button->irq; 583 } else { 584 irq = gpiod_to_irq(bdata->gpiod); 585 if (irq < 0) { 586 error = irq; 587 dev_err(dev, 588 "Unable to get irq number for GPIO %d, error %d\n", 589 button->gpio, error); 590 return error; 591 } 592 bdata->irq = irq; 593 } 594 595 INIT_DELAYED_WORK(&bdata->work, gpio_keys_gpio_work_func); 596 597 hrtimer_init(&bdata->debounce_timer, 598 CLOCK_REALTIME, HRTIMER_MODE_REL); 599 bdata->debounce_timer.function = gpio_keys_debounce_timer; 600 601 isr = gpio_keys_gpio_isr; 602 irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING; 603 604 switch (button->wakeup_event_action) { 605 case EV_ACT_ASSERTED: 606 bdata->wakeup_trigger_type = active_low ? 607 IRQ_TYPE_EDGE_FALLING : IRQ_TYPE_EDGE_RISING; 608 break; 609 case EV_ACT_DEASSERTED: 610 bdata->wakeup_trigger_type = active_low ? 611 IRQ_TYPE_EDGE_RISING : IRQ_TYPE_EDGE_FALLING; 612 break; 613 case EV_ACT_ANY: 614 default: 615 /* 616 * For other cases, we are OK letting suspend/resume 617 * not reconfigure the trigger type. 618 */ 619 break; 620 } 621 } else { 622 if (!button->irq) { 623 dev_err(dev, "Found button without gpio or irq\n"); 624 return -EINVAL; 625 } 626 627 bdata->irq = button->irq; 628 629 if (button->type && button->type != EV_KEY) { 630 dev_err(dev, "Only EV_KEY allowed for IRQ buttons.\n"); 631 return -EINVAL; 632 } 633 634 bdata->release_delay = button->debounce_interval; 635 hrtimer_init(&bdata->release_timer, 636 CLOCK_REALTIME, HRTIMER_MODE_REL_HARD); 637 bdata->release_timer.function = gpio_keys_irq_timer; 638 639 isr = gpio_keys_irq_isr; 640 irqflags = 0; 641 642 /* 643 * For IRQ buttons, there is no interrupt for release. 644 * So we don't need to reconfigure the trigger type for wakeup. 645 */ 646 } 647 648 bdata->code = &ddata->keymap[idx]; 649 *bdata->code = button->code; 650 input_set_capability(input, button->type ?: EV_KEY, *bdata->code); 651 652 /* 653 * Install custom action to cancel release timer and 654 * workqueue item. 655 */ 656 error = devm_add_action(dev, gpio_keys_quiesce_key, bdata); 657 if (error) { 658 dev_err(dev, "failed to register quiesce action, error: %d\n", 659 error); 660 return error; 661 } 662 663 /* 664 * If platform has specified that the button can be disabled, 665 * we don't want it to share the interrupt line. 666 */ 667 if (!button->can_disable) 668 irqflags |= IRQF_SHARED; 669 670 error = devm_request_any_context_irq(dev, bdata->irq, isr, irqflags, 671 desc, bdata); 672 if (error < 0) { 673 dev_err(dev, "Unable to claim irq %d; error %d\n", 674 bdata->irq, error); 675 return error; 676 } 677 678 return 0; 679 } 680 681 static void gpio_keys_report_state(struct gpio_keys_drvdata *ddata) 682 { 683 struct input_dev *input = ddata->input; 684 int i; 685 686 for (i = 0; i < ddata->pdata->nbuttons; i++) { 687 struct gpio_button_data *bdata = &ddata->data[i]; 688 if (bdata->gpiod) 689 gpio_keys_gpio_report_event(bdata); 690 } 691 input_sync(input); 692 } 693 694 static int gpio_keys_open(struct input_dev *input) 695 { 696 struct gpio_keys_drvdata *ddata = input_get_drvdata(input); 697 const struct gpio_keys_platform_data *pdata = ddata->pdata; 698 int error; 699 700 if (pdata->enable) { 701 error = pdata->enable(input->dev.parent); 702 if (error) 703 return error; 704 } 705 706 /* Report current state of buttons that are connected to GPIOs */ 707 gpio_keys_report_state(ddata); 708 709 return 0; 710 } 711 712 static void gpio_keys_close(struct input_dev *input) 713 { 714 struct gpio_keys_drvdata *ddata = input_get_drvdata(input); 715 const struct gpio_keys_platform_data *pdata = ddata->pdata; 716 717 if (pdata->disable) 718 pdata->disable(input->dev.parent); 719 } 720 721 /* 722 * Handlers for alternative sources of platform_data 723 */ 724 725 /* 726 * Translate properties into platform_data 727 */ 728 static struct gpio_keys_platform_data * 729 gpio_keys_get_devtree_pdata(struct device *dev) 730 { 731 struct gpio_keys_platform_data *pdata; 732 struct gpio_keys_button *button; 733 struct fwnode_handle *child; 734 int nbuttons; 735 736 nbuttons = device_get_child_node_count(dev); 737 if (nbuttons == 0) 738 return ERR_PTR(-ENODEV); 739 740 pdata = devm_kzalloc(dev, 741 sizeof(*pdata) + nbuttons * sizeof(*button), 742 GFP_KERNEL); 743 if (!pdata) 744 return ERR_PTR(-ENOMEM); 745 746 button = (struct gpio_keys_button *)(pdata + 1); 747 748 pdata->buttons = button; 749 pdata->nbuttons = nbuttons; 750 751 pdata->rep = device_property_read_bool(dev, "autorepeat"); 752 753 device_property_read_string(dev, "label", &pdata->name); 754 755 device_for_each_child_node(dev, child) { 756 if (is_of_node(child)) 757 button->irq = 758 irq_of_parse_and_map(to_of_node(child), 0); 759 760 if (fwnode_property_read_u32(child, "linux,code", 761 &button->code)) { 762 dev_err(dev, "Button without keycode\n"); 763 fwnode_handle_put(child); 764 return ERR_PTR(-EINVAL); 765 } 766 767 fwnode_property_read_string(child, "label", &button->desc); 768 769 if (fwnode_property_read_u32(child, "linux,input-type", 770 &button->type)) 771 button->type = EV_KEY; 772 773 fwnode_property_read_u32(child, "linux,input-value", 774 (u32 *)&button->value); 775 776 button->wakeup = 777 fwnode_property_read_bool(child, "wakeup-source") || 778 /* legacy name */ 779 fwnode_property_read_bool(child, "gpio-key,wakeup"); 780 781 fwnode_property_read_u32(child, "wakeup-event-action", 782 &button->wakeup_event_action); 783 784 button->can_disable = 785 fwnode_property_read_bool(child, "linux,can-disable"); 786 787 if (fwnode_property_read_u32(child, "debounce-interval", 788 &button->debounce_interval)) 789 button->debounce_interval = 5; 790 791 button++; 792 } 793 794 return pdata; 795 } 796 797 static const struct of_device_id gpio_keys_of_match[] = { 798 { .compatible = "gpio-keys", }, 799 { }, 800 }; 801 MODULE_DEVICE_TABLE(of, gpio_keys_of_match); 802 803 static int gpio_keys_probe(struct platform_device *pdev) 804 { 805 struct device *dev = &pdev->dev; 806 const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev); 807 struct fwnode_handle *child = NULL; 808 struct gpio_keys_drvdata *ddata; 809 struct input_dev *input; 810 int i, error; 811 int wakeup = 0; 812 813 if (!pdata) { 814 pdata = gpio_keys_get_devtree_pdata(dev); 815 if (IS_ERR(pdata)) 816 return PTR_ERR(pdata); 817 } 818 819 ddata = devm_kzalloc(dev, struct_size(ddata, data, pdata->nbuttons), 820 GFP_KERNEL); 821 if (!ddata) { 822 dev_err(dev, "failed to allocate state\n"); 823 return -ENOMEM; 824 } 825 826 ddata->keymap = devm_kcalloc(dev, 827 pdata->nbuttons, sizeof(ddata->keymap[0]), 828 GFP_KERNEL); 829 if (!ddata->keymap) 830 return -ENOMEM; 831 832 input = devm_input_allocate_device(dev); 833 if (!input) { 834 dev_err(dev, "failed to allocate input device\n"); 835 return -ENOMEM; 836 } 837 838 ddata->pdata = pdata; 839 ddata->input = input; 840 mutex_init(&ddata->disable_lock); 841 842 platform_set_drvdata(pdev, ddata); 843 input_set_drvdata(input, ddata); 844 845 input->name = pdata->name ? : pdev->name; 846 input->phys = "gpio-keys/input0"; 847 input->dev.parent = dev; 848 input->open = gpio_keys_open; 849 input->close = gpio_keys_close; 850 851 input->id.bustype = BUS_HOST; 852 input->id.vendor = 0x0001; 853 input->id.product = 0x0001; 854 input->id.version = 0x0100; 855 856 input->keycode = ddata->keymap; 857 input->keycodesize = sizeof(ddata->keymap[0]); 858 input->keycodemax = pdata->nbuttons; 859 860 /* Enable auto repeat feature of Linux input subsystem */ 861 if (pdata->rep) 862 __set_bit(EV_REP, input->evbit); 863 864 for (i = 0; i < pdata->nbuttons; i++) { 865 const struct gpio_keys_button *button = &pdata->buttons[i]; 866 867 if (!dev_get_platdata(dev)) { 868 child = device_get_next_child_node(dev, child); 869 if (!child) { 870 dev_err(dev, 871 "missing child device node for entry %d\n", 872 i); 873 return -EINVAL; 874 } 875 } 876 877 error = gpio_keys_setup_key(pdev, input, ddata, 878 button, i, child); 879 if (error) { 880 fwnode_handle_put(child); 881 return error; 882 } 883 884 if (button->wakeup) 885 wakeup = 1; 886 } 887 888 fwnode_handle_put(child); 889 890 error = input_register_device(input); 891 if (error) { 892 dev_err(dev, "Unable to register input device, error: %d\n", 893 error); 894 return error; 895 } 896 897 device_init_wakeup(dev, wakeup); 898 899 return 0; 900 } 901 902 static int __maybe_unused 903 gpio_keys_button_enable_wakeup(struct gpio_button_data *bdata) 904 { 905 int error; 906 907 error = enable_irq_wake(bdata->irq); 908 if (error) { 909 dev_err(bdata->input->dev.parent, 910 "failed to configure IRQ %d as wakeup source: %d\n", 911 bdata->irq, error); 912 return error; 913 } 914 915 if (bdata->wakeup_trigger_type) { 916 error = irq_set_irq_type(bdata->irq, 917 bdata->wakeup_trigger_type); 918 if (error) { 919 dev_err(bdata->input->dev.parent, 920 "failed to set wakeup trigger %08x for IRQ %d: %d\n", 921 bdata->wakeup_trigger_type, bdata->irq, error); 922 disable_irq_wake(bdata->irq); 923 return error; 924 } 925 } 926 927 return 0; 928 } 929 930 static void __maybe_unused 931 gpio_keys_button_disable_wakeup(struct gpio_button_data *bdata) 932 { 933 int error; 934 935 /* 936 * The trigger type is always both edges for gpio-based keys and we do 937 * not support changing wakeup trigger for interrupt-based keys. 938 */ 939 if (bdata->wakeup_trigger_type) { 940 error = irq_set_irq_type(bdata->irq, IRQ_TYPE_EDGE_BOTH); 941 if (error) 942 dev_warn(bdata->input->dev.parent, 943 "failed to restore interrupt trigger for IRQ %d: %d\n", 944 bdata->irq, error); 945 } 946 947 error = disable_irq_wake(bdata->irq); 948 if (error) 949 dev_warn(bdata->input->dev.parent, 950 "failed to disable IRQ %d as wake source: %d\n", 951 bdata->irq, error); 952 } 953 954 static int __maybe_unused 955 gpio_keys_enable_wakeup(struct gpio_keys_drvdata *ddata) 956 { 957 struct gpio_button_data *bdata; 958 int error; 959 int i; 960 961 for (i = 0; i < ddata->pdata->nbuttons; i++) { 962 bdata = &ddata->data[i]; 963 if (bdata->button->wakeup) { 964 error = gpio_keys_button_enable_wakeup(bdata); 965 if (error) 966 goto err_out; 967 } 968 bdata->suspended = true; 969 } 970 971 return 0; 972 973 err_out: 974 while (i--) { 975 bdata = &ddata->data[i]; 976 if (bdata->button->wakeup) 977 gpio_keys_button_disable_wakeup(bdata); 978 bdata->suspended = false; 979 } 980 981 return error; 982 } 983 984 static void __maybe_unused 985 gpio_keys_disable_wakeup(struct gpio_keys_drvdata *ddata) 986 { 987 struct gpio_button_data *bdata; 988 int i; 989 990 for (i = 0; i < ddata->pdata->nbuttons; i++) { 991 bdata = &ddata->data[i]; 992 bdata->suspended = false; 993 if (irqd_is_wakeup_set(irq_get_irq_data(bdata->irq))) 994 gpio_keys_button_disable_wakeup(bdata); 995 } 996 } 997 998 static int gpio_keys_suspend(struct device *dev) 999 { 1000 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); 1001 struct input_dev *input = ddata->input; 1002 int error; 1003 1004 if (device_may_wakeup(dev)) { 1005 error = gpio_keys_enable_wakeup(ddata); 1006 if (error) 1007 return error; 1008 } else { 1009 mutex_lock(&input->mutex); 1010 if (input_device_enabled(input)) 1011 gpio_keys_close(input); 1012 mutex_unlock(&input->mutex); 1013 } 1014 1015 return 0; 1016 } 1017 1018 static int gpio_keys_resume(struct device *dev) 1019 { 1020 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); 1021 struct input_dev *input = ddata->input; 1022 int error = 0; 1023 1024 if (device_may_wakeup(dev)) { 1025 gpio_keys_disable_wakeup(ddata); 1026 } else { 1027 mutex_lock(&input->mutex); 1028 if (input_device_enabled(input)) 1029 error = gpio_keys_open(input); 1030 mutex_unlock(&input->mutex); 1031 } 1032 1033 if (error) 1034 return error; 1035 1036 gpio_keys_report_state(ddata); 1037 return 0; 1038 } 1039 1040 static DEFINE_SIMPLE_DEV_PM_OPS(gpio_keys_pm_ops, gpio_keys_suspend, gpio_keys_resume); 1041 1042 static void gpio_keys_shutdown(struct platform_device *pdev) 1043 { 1044 int ret; 1045 1046 ret = gpio_keys_suspend(&pdev->dev); 1047 if (ret) 1048 dev_err(&pdev->dev, "failed to shutdown\n"); 1049 } 1050 1051 static struct platform_driver gpio_keys_device_driver = { 1052 .probe = gpio_keys_probe, 1053 .shutdown = gpio_keys_shutdown, 1054 .driver = { 1055 .name = "gpio-keys", 1056 .pm = pm_sleep_ptr(&gpio_keys_pm_ops), 1057 .of_match_table = gpio_keys_of_match, 1058 .dev_groups = gpio_keys_groups, 1059 } 1060 }; 1061 1062 static int __init gpio_keys_init(void) 1063 { 1064 return platform_driver_register(&gpio_keys_device_driver); 1065 } 1066 1067 static void __exit gpio_keys_exit(void) 1068 { 1069 platform_driver_unregister(&gpio_keys_device_driver); 1070 } 1071 1072 late_initcall(gpio_keys_init); 1073 module_exit(gpio_keys_exit); 1074 1075 MODULE_LICENSE("GPL"); 1076 MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>"); 1077 MODULE_DESCRIPTION("Keyboard driver for GPIOs"); 1078 MODULE_ALIAS("platform:gpio-keys"); 1079