1 /* 2 * Driver for keys on GPIO lines capable of generating interrupts. 3 * 4 * Copyright 2005 Phil Blundell 5 * Copyright 2010, 2011 David Jander <david@protonic.nl> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 */ 11 12 #include <linux/module.h> 13 14 #include <linux/init.h> 15 #include <linux/fs.h> 16 #include <linux/interrupt.h> 17 #include <linux/irq.h> 18 #include <linux/sched.h> 19 #include <linux/pm.h> 20 #include <linux/slab.h> 21 #include <linux/sysctl.h> 22 #include <linux/proc_fs.h> 23 #include <linux/delay.h> 24 #include <linux/platform_device.h> 25 #include <linux/input.h> 26 #include <linux/gpio_keys.h> 27 #include <linux/workqueue.h> 28 #include <linux/gpio.h> 29 #include <linux/gpio/consumer.h> 30 #include <linux/of.h> 31 #include <linux/of_irq.h> 32 #include <linux/spinlock.h> 33 34 struct gpio_button_data { 35 const struct gpio_keys_button *button; 36 struct input_dev *input; 37 struct gpio_desc *gpiod; 38 39 unsigned short *code; 40 41 struct timer_list release_timer; 42 unsigned int release_delay; /* in msecs, for IRQ-only buttons */ 43 44 struct delayed_work work; 45 unsigned int software_debounce; /* in msecs, for GPIO-driven buttons */ 46 47 unsigned int irq; 48 spinlock_t lock; 49 bool disabled; 50 bool key_pressed; 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 = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), 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 kfree(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 = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), 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 kfree(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 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 pm_stay_awake(bdata->input->dev.parent); 401 402 mod_delayed_work(system_wq, 403 &bdata->work, 404 msecs_to_jiffies(bdata->software_debounce)); 405 406 return IRQ_HANDLED; 407 } 408 409 static void gpio_keys_irq_timer(unsigned long _data) 410 { 411 struct gpio_button_data *bdata = (struct gpio_button_data *)_data; 412 struct input_dev *input = bdata->input; 413 unsigned long flags; 414 415 spin_lock_irqsave(&bdata->lock, flags); 416 if (bdata->key_pressed) { 417 input_event(input, EV_KEY, *bdata->code, 0); 418 input_sync(input); 419 bdata->key_pressed = false; 420 } 421 spin_unlock_irqrestore(&bdata->lock, flags); 422 } 423 424 static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id) 425 { 426 struct gpio_button_data *bdata = dev_id; 427 struct input_dev *input = bdata->input; 428 unsigned long flags; 429 430 BUG_ON(irq != bdata->irq); 431 432 spin_lock_irqsave(&bdata->lock, flags); 433 434 if (!bdata->key_pressed) { 435 if (bdata->button->wakeup) 436 pm_wakeup_event(bdata->input->dev.parent, 0); 437 438 input_event(input, EV_KEY, *bdata->code, 1); 439 input_sync(input); 440 441 if (!bdata->release_delay) { 442 input_event(input, EV_KEY, *bdata->code, 0); 443 input_sync(input); 444 goto out; 445 } 446 447 bdata->key_pressed = true; 448 } 449 450 if (bdata->release_delay) 451 mod_timer(&bdata->release_timer, 452 jiffies + msecs_to_jiffies(bdata->release_delay)); 453 out: 454 spin_unlock_irqrestore(&bdata->lock, flags); 455 return IRQ_HANDLED; 456 } 457 458 static void gpio_keys_quiesce_key(void *data) 459 { 460 struct gpio_button_data *bdata = data; 461 462 if (bdata->gpiod) 463 cancel_delayed_work_sync(&bdata->work); 464 else 465 del_timer_sync(&bdata->release_timer); 466 } 467 468 static int gpio_keys_setup_key(struct platform_device *pdev, 469 struct input_dev *input, 470 struct gpio_keys_drvdata *ddata, 471 const struct gpio_keys_button *button, 472 int idx, 473 struct fwnode_handle *child) 474 { 475 const char *desc = button->desc ? button->desc : "gpio_keys"; 476 struct device *dev = &pdev->dev; 477 struct gpio_button_data *bdata = &ddata->data[idx]; 478 irq_handler_t isr; 479 unsigned long irqflags; 480 int irq; 481 int error; 482 483 bdata->input = input; 484 bdata->button = button; 485 spin_lock_init(&bdata->lock); 486 487 if (child) { 488 bdata->gpiod = devm_fwnode_get_gpiod_from_child(dev, NULL, 489 child, 490 GPIOD_IN, 491 desc); 492 if (IS_ERR(bdata->gpiod)) { 493 error = PTR_ERR(bdata->gpiod); 494 if (error == -ENOENT) { 495 /* 496 * GPIO is optional, we may be dealing with 497 * purely interrupt-driven setup. 498 */ 499 bdata->gpiod = NULL; 500 } else { 501 if (error != -EPROBE_DEFER) 502 dev_err(dev, "failed to get gpio: %d\n", 503 error); 504 return error; 505 } 506 } 507 } else if (gpio_is_valid(button->gpio)) { 508 /* 509 * Legacy GPIO number, so request the GPIO here and 510 * convert it to descriptor. 511 */ 512 unsigned flags = GPIOF_IN; 513 514 if (button->active_low) 515 flags |= GPIOF_ACTIVE_LOW; 516 517 error = devm_gpio_request_one(dev, button->gpio, flags, desc); 518 if (error < 0) { 519 dev_err(dev, "Failed to request GPIO %d, error %d\n", 520 button->gpio, error); 521 return error; 522 } 523 524 bdata->gpiod = gpio_to_desc(button->gpio); 525 if (!bdata->gpiod) 526 return -EINVAL; 527 } 528 529 if (bdata->gpiod) { 530 if (button->debounce_interval) { 531 error = gpiod_set_debounce(bdata->gpiod, 532 button->debounce_interval * 1000); 533 /* use timer if gpiolib doesn't provide debounce */ 534 if (error < 0) 535 bdata->software_debounce = 536 button->debounce_interval; 537 } 538 539 if (button->irq) { 540 bdata->irq = button->irq; 541 } else { 542 irq = gpiod_to_irq(bdata->gpiod); 543 if (irq < 0) { 544 error = irq; 545 dev_err(dev, 546 "Unable to get irq number for GPIO %d, error %d\n", 547 button->gpio, error); 548 return error; 549 } 550 bdata->irq = irq; 551 } 552 553 INIT_DELAYED_WORK(&bdata->work, gpio_keys_gpio_work_func); 554 555 isr = gpio_keys_gpio_isr; 556 irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING; 557 558 } else { 559 if (!button->irq) { 560 dev_err(dev, "Found button without gpio or irq\n"); 561 return -EINVAL; 562 } 563 564 bdata->irq = button->irq; 565 566 if (button->type && button->type != EV_KEY) { 567 dev_err(dev, "Only EV_KEY allowed for IRQ buttons.\n"); 568 return -EINVAL; 569 } 570 571 bdata->release_delay = button->debounce_interval; 572 setup_timer(&bdata->release_timer, 573 gpio_keys_irq_timer, (unsigned long)bdata); 574 575 isr = gpio_keys_irq_isr; 576 irqflags = 0; 577 } 578 579 bdata->code = &ddata->keymap[idx]; 580 *bdata->code = button->code; 581 input_set_capability(input, button->type ?: EV_KEY, *bdata->code); 582 583 /* 584 * Install custom action to cancel release timer and 585 * workqueue item. 586 */ 587 error = devm_add_action(dev, gpio_keys_quiesce_key, bdata); 588 if (error) { 589 dev_err(dev, "failed to register quiesce action, error: %d\n", 590 error); 591 return error; 592 } 593 594 /* 595 * If platform has specified that the button can be disabled, 596 * we don't want it to share the interrupt line. 597 */ 598 if (!button->can_disable) 599 irqflags |= IRQF_SHARED; 600 601 error = devm_request_any_context_irq(dev, bdata->irq, isr, irqflags, 602 desc, bdata); 603 if (error < 0) { 604 dev_err(dev, "Unable to claim irq %d; error %d\n", 605 bdata->irq, error); 606 return error; 607 } 608 609 return 0; 610 } 611 612 static void gpio_keys_report_state(struct gpio_keys_drvdata *ddata) 613 { 614 struct input_dev *input = ddata->input; 615 int i; 616 617 for (i = 0; i < ddata->pdata->nbuttons; i++) { 618 struct gpio_button_data *bdata = &ddata->data[i]; 619 if (bdata->gpiod) 620 gpio_keys_gpio_report_event(bdata); 621 } 622 input_sync(input); 623 } 624 625 static int gpio_keys_open(struct input_dev *input) 626 { 627 struct gpio_keys_drvdata *ddata = input_get_drvdata(input); 628 const struct gpio_keys_platform_data *pdata = ddata->pdata; 629 int error; 630 631 if (pdata->enable) { 632 error = pdata->enable(input->dev.parent); 633 if (error) 634 return error; 635 } 636 637 /* Report current state of buttons that are connected to GPIOs */ 638 gpio_keys_report_state(ddata); 639 640 return 0; 641 } 642 643 static void gpio_keys_close(struct input_dev *input) 644 { 645 struct gpio_keys_drvdata *ddata = input_get_drvdata(input); 646 const struct gpio_keys_platform_data *pdata = ddata->pdata; 647 648 if (pdata->disable) 649 pdata->disable(input->dev.parent); 650 } 651 652 /* 653 * Handlers for alternative sources of platform_data 654 */ 655 656 /* 657 * Translate properties into platform_data 658 */ 659 static struct gpio_keys_platform_data * 660 gpio_keys_get_devtree_pdata(struct device *dev) 661 { 662 struct gpio_keys_platform_data *pdata; 663 struct gpio_keys_button *button; 664 struct fwnode_handle *child; 665 int nbuttons; 666 667 nbuttons = device_get_child_node_count(dev); 668 if (nbuttons == 0) 669 return ERR_PTR(-ENODEV); 670 671 pdata = devm_kzalloc(dev, 672 sizeof(*pdata) + nbuttons * sizeof(*button), 673 GFP_KERNEL); 674 if (!pdata) 675 return ERR_PTR(-ENOMEM); 676 677 button = (struct gpio_keys_button *)(pdata + 1); 678 679 pdata->buttons = button; 680 pdata->nbuttons = nbuttons; 681 682 pdata->rep = device_property_read_bool(dev, "autorepeat"); 683 684 device_property_read_string(dev, "label", &pdata->name); 685 686 device_for_each_child_node(dev, child) { 687 if (is_of_node(child)) 688 button->irq = 689 irq_of_parse_and_map(to_of_node(child), 0); 690 691 if (fwnode_property_read_u32(child, "linux,code", 692 &button->code)) { 693 dev_err(dev, "Button without keycode\n"); 694 fwnode_handle_put(child); 695 return ERR_PTR(-EINVAL); 696 } 697 698 fwnode_property_read_string(child, "label", &button->desc); 699 700 if (fwnode_property_read_u32(child, "linux,input-type", 701 &button->type)) 702 button->type = EV_KEY; 703 704 button->wakeup = 705 fwnode_property_read_bool(child, "wakeup-source") || 706 /* legacy name */ 707 fwnode_property_read_bool(child, "gpio-key,wakeup"); 708 709 button->can_disable = 710 fwnode_property_read_bool(child, "linux,can-disable"); 711 712 if (fwnode_property_read_u32(child, "debounce-interval", 713 &button->debounce_interval)) 714 button->debounce_interval = 5; 715 716 button++; 717 } 718 719 return pdata; 720 } 721 722 static const struct of_device_id gpio_keys_of_match[] = { 723 { .compatible = "gpio-keys", }, 724 { }, 725 }; 726 MODULE_DEVICE_TABLE(of, gpio_keys_of_match); 727 728 static int gpio_keys_probe(struct platform_device *pdev) 729 { 730 struct device *dev = &pdev->dev; 731 const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev); 732 struct fwnode_handle *child = NULL; 733 struct gpio_keys_drvdata *ddata; 734 struct input_dev *input; 735 size_t size; 736 int i, error; 737 int wakeup = 0; 738 739 if (!pdata) { 740 pdata = gpio_keys_get_devtree_pdata(dev); 741 if (IS_ERR(pdata)) 742 return PTR_ERR(pdata); 743 } 744 745 size = sizeof(struct gpio_keys_drvdata) + 746 pdata->nbuttons * sizeof(struct gpio_button_data); 747 ddata = devm_kzalloc(dev, size, GFP_KERNEL); 748 if (!ddata) { 749 dev_err(dev, "failed to allocate state\n"); 750 return -ENOMEM; 751 } 752 753 ddata->keymap = devm_kcalloc(dev, 754 pdata->nbuttons, sizeof(ddata->keymap[0]), 755 GFP_KERNEL); 756 if (!ddata->keymap) 757 return -ENOMEM; 758 759 input = devm_input_allocate_device(dev); 760 if (!input) { 761 dev_err(dev, "failed to allocate input device\n"); 762 return -ENOMEM; 763 } 764 765 ddata->pdata = pdata; 766 ddata->input = input; 767 mutex_init(&ddata->disable_lock); 768 769 platform_set_drvdata(pdev, ddata); 770 input_set_drvdata(input, ddata); 771 772 input->name = pdata->name ? : pdev->name; 773 input->phys = "gpio-keys/input0"; 774 input->dev.parent = dev; 775 input->open = gpio_keys_open; 776 input->close = gpio_keys_close; 777 778 input->id.bustype = BUS_HOST; 779 input->id.vendor = 0x0001; 780 input->id.product = 0x0001; 781 input->id.version = 0x0100; 782 783 input->keycode = ddata->keymap; 784 input->keycodesize = sizeof(ddata->keymap[0]); 785 input->keycodemax = pdata->nbuttons; 786 787 /* Enable auto repeat feature of Linux input subsystem */ 788 if (pdata->rep) 789 __set_bit(EV_REP, input->evbit); 790 791 for (i = 0; i < pdata->nbuttons; i++) { 792 const struct gpio_keys_button *button = &pdata->buttons[i]; 793 794 if (!dev_get_platdata(dev)) { 795 child = device_get_next_child_node(dev, child); 796 if (!child) { 797 dev_err(dev, 798 "missing child device node for entry %d\n", 799 i); 800 return -EINVAL; 801 } 802 } 803 804 error = gpio_keys_setup_key(pdev, input, ddata, 805 button, i, child); 806 if (error) { 807 fwnode_handle_put(child); 808 return error; 809 } 810 811 if (button->wakeup) 812 wakeup = 1; 813 } 814 815 fwnode_handle_put(child); 816 817 error = sysfs_create_group(&dev->kobj, &gpio_keys_attr_group); 818 if (error) { 819 dev_err(dev, "Unable to export keys/switches, error: %d\n", 820 error); 821 return error; 822 } 823 824 error = input_register_device(input); 825 if (error) { 826 dev_err(dev, "Unable to register input device, error: %d\n", 827 error); 828 goto err_remove_group; 829 } 830 831 device_init_wakeup(dev, wakeup); 832 833 return 0; 834 835 err_remove_group: 836 sysfs_remove_group(&dev->kobj, &gpio_keys_attr_group); 837 return error; 838 } 839 840 static int gpio_keys_remove(struct platform_device *pdev) 841 { 842 sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group); 843 844 return 0; 845 } 846 847 static int __maybe_unused gpio_keys_suspend(struct device *dev) 848 { 849 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); 850 struct input_dev *input = ddata->input; 851 int i; 852 853 if (device_may_wakeup(dev)) { 854 for (i = 0; i < ddata->pdata->nbuttons; i++) { 855 struct gpio_button_data *bdata = &ddata->data[i]; 856 if (bdata->button->wakeup) 857 enable_irq_wake(bdata->irq); 858 } 859 } else { 860 mutex_lock(&input->mutex); 861 if (input->users) 862 gpio_keys_close(input); 863 mutex_unlock(&input->mutex); 864 } 865 866 return 0; 867 } 868 869 static int __maybe_unused gpio_keys_resume(struct device *dev) 870 { 871 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); 872 struct input_dev *input = ddata->input; 873 int error = 0; 874 int i; 875 876 if (device_may_wakeup(dev)) { 877 for (i = 0; i < ddata->pdata->nbuttons; i++) { 878 struct gpio_button_data *bdata = &ddata->data[i]; 879 if (bdata->button->wakeup) 880 disable_irq_wake(bdata->irq); 881 } 882 } else { 883 mutex_lock(&input->mutex); 884 if (input->users) 885 error = gpio_keys_open(input); 886 mutex_unlock(&input->mutex); 887 } 888 889 if (error) 890 return error; 891 892 gpio_keys_report_state(ddata); 893 return 0; 894 } 895 896 static SIMPLE_DEV_PM_OPS(gpio_keys_pm_ops, gpio_keys_suspend, gpio_keys_resume); 897 898 static struct platform_driver gpio_keys_device_driver = { 899 .probe = gpio_keys_probe, 900 .remove = gpio_keys_remove, 901 .driver = { 902 .name = "gpio-keys", 903 .pm = &gpio_keys_pm_ops, 904 .of_match_table = gpio_keys_of_match, 905 } 906 }; 907 908 static int __init gpio_keys_init(void) 909 { 910 return platform_driver_register(&gpio_keys_device_driver); 911 } 912 913 static void __exit gpio_keys_exit(void) 914 { 915 platform_driver_unregister(&gpio_keys_device_driver); 916 } 917 918 late_initcall(gpio_keys_init); 919 module_exit(gpio_keys_exit); 920 921 MODULE_LICENSE("GPL"); 922 MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>"); 923 MODULE_DESCRIPTION("Keyboard driver for GPIOs"); 924 MODULE_ALIAS("platform:gpio-keys"); 925