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/of.h> 30 #include <linux/of_platform.h> 31 #include <linux/of_gpio.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 timer_list timer; 38 struct work_struct work; 39 unsigned int timer_debounce; /* in msecs */ 40 unsigned int irq; 41 spinlock_t lock; 42 bool disabled; 43 bool key_pressed; 44 }; 45 46 struct gpio_keys_drvdata { 47 const struct gpio_keys_platform_data *pdata; 48 struct input_dev *input; 49 struct mutex disable_lock; 50 struct gpio_button_data data[0]; 51 }; 52 53 /* 54 * SYSFS interface for enabling/disabling keys and switches: 55 * 56 * There are 4 attributes under /sys/devices/platform/gpio-keys/ 57 * keys [ro] - bitmap of keys (EV_KEY) which can be 58 * disabled 59 * switches [ro] - bitmap of switches (EV_SW) which can be 60 * disabled 61 * disabled_keys [rw] - bitmap of keys currently disabled 62 * disabled_switches [rw] - bitmap of switches currently disabled 63 * 64 * Userland can change these values and hence disable event generation 65 * for each key (or switch). Disabling a key means its interrupt line 66 * is disabled. 67 * 68 * For example, if we have following switches set up as gpio-keys: 69 * SW_DOCK = 5 70 * SW_CAMERA_LENS_COVER = 9 71 * SW_KEYPAD_SLIDE = 10 72 * SW_FRONT_PROXIMITY = 11 73 * This is read from switches: 74 * 11-9,5 75 * Next we want to disable proximity (11) and dock (5), we write: 76 * 11,5 77 * to file disabled_switches. Now proximity and dock IRQs are disabled. 78 * This can be verified by reading the file disabled_switches: 79 * 11,5 80 * If we now want to enable proximity (11) switch we write: 81 * 5 82 * to disabled_switches. 83 * 84 * We can disable only those keys which don't allow sharing the irq. 85 */ 86 87 /** 88 * get_n_events_by_type() - returns maximum number of events per @type 89 * @type: type of button (%EV_KEY, %EV_SW) 90 * 91 * Return value of this function can be used to allocate bitmap 92 * large enough to hold all bits for given type. 93 */ 94 static inline int get_n_events_by_type(int type) 95 { 96 BUG_ON(type != EV_SW && type != EV_KEY); 97 98 return (type == EV_KEY) ? KEY_CNT : SW_CNT; 99 } 100 101 /** 102 * gpio_keys_disable_button() - disables given GPIO button 103 * @bdata: button data for button to be disabled 104 * 105 * Disables button pointed by @bdata. This is done by masking 106 * IRQ line. After this function is called, button won't generate 107 * input events anymore. Note that one can only disable buttons 108 * that don't share IRQs. 109 * 110 * Make sure that @bdata->disable_lock is locked when entering 111 * this function to avoid races when concurrent threads are 112 * disabling buttons at the same time. 113 */ 114 static void gpio_keys_disable_button(struct gpio_button_data *bdata) 115 { 116 if (!bdata->disabled) { 117 /* 118 * Disable IRQ and possible debouncing timer. 119 */ 120 disable_irq(bdata->irq); 121 if (bdata->timer_debounce) 122 del_timer_sync(&bdata->timer); 123 124 bdata->disabled = true; 125 } 126 } 127 128 /** 129 * gpio_keys_enable_button() - enables given GPIO button 130 * @bdata: button data for button to be disabled 131 * 132 * Enables given button pointed by @bdata. 133 * 134 * Make sure that @bdata->disable_lock is locked when entering 135 * this function to avoid races with concurrent threads trying 136 * to enable the same button at the same time. 137 */ 138 static void gpio_keys_enable_button(struct gpio_button_data *bdata) 139 { 140 if (bdata->disabled) { 141 enable_irq(bdata->irq); 142 bdata->disabled = false; 143 } 144 } 145 146 /** 147 * gpio_keys_attr_show_helper() - fill in stringified bitmap of buttons 148 * @ddata: pointer to drvdata 149 * @buf: buffer where stringified bitmap is written 150 * @type: button type (%EV_KEY, %EV_SW) 151 * @only_disabled: does caller want only those buttons that are 152 * currently disabled or all buttons that can be 153 * disabled 154 * 155 * This function writes buttons that can be disabled to @buf. If 156 * @only_disabled is true, then @buf contains only those buttons 157 * that are currently disabled. Returns 0 on success or negative 158 * errno on failure. 159 */ 160 static ssize_t gpio_keys_attr_show_helper(struct gpio_keys_drvdata *ddata, 161 char *buf, unsigned int type, 162 bool only_disabled) 163 { 164 int n_events = get_n_events_by_type(type); 165 unsigned long *bits; 166 ssize_t ret; 167 int i; 168 169 bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL); 170 if (!bits) 171 return -ENOMEM; 172 173 for (i = 0; i < ddata->pdata->nbuttons; i++) { 174 struct gpio_button_data *bdata = &ddata->data[i]; 175 176 if (bdata->button->type != type) 177 continue; 178 179 if (only_disabled && !bdata->disabled) 180 continue; 181 182 __set_bit(bdata->button->code, bits); 183 } 184 185 ret = bitmap_scnlistprintf(buf, PAGE_SIZE - 2, bits, n_events); 186 buf[ret++] = '\n'; 187 buf[ret] = '\0'; 188 189 kfree(bits); 190 191 return ret; 192 } 193 194 /** 195 * gpio_keys_attr_store_helper() - enable/disable buttons based on given bitmap 196 * @ddata: pointer to drvdata 197 * @buf: buffer from userspace that contains stringified bitmap 198 * @type: button type (%EV_KEY, %EV_SW) 199 * 200 * This function parses stringified bitmap from @buf and disables/enables 201 * GPIO buttons accordingly. Returns 0 on success and negative error 202 * on failure. 203 */ 204 static ssize_t gpio_keys_attr_store_helper(struct gpio_keys_drvdata *ddata, 205 const char *buf, unsigned int type) 206 { 207 int n_events = get_n_events_by_type(type); 208 unsigned long *bits; 209 ssize_t error; 210 int i; 211 212 bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL); 213 if (!bits) 214 return -ENOMEM; 215 216 error = bitmap_parselist(buf, bits, n_events); 217 if (error) 218 goto out; 219 220 /* First validate */ 221 for (i = 0; i < ddata->pdata->nbuttons; i++) { 222 struct gpio_button_data *bdata = &ddata->data[i]; 223 224 if (bdata->button->type != type) 225 continue; 226 227 if (test_bit(bdata->button->code, bits) && 228 !bdata->button->can_disable) { 229 error = -EINVAL; 230 goto out; 231 } 232 } 233 234 mutex_lock(&ddata->disable_lock); 235 236 for (i = 0; i < ddata->pdata->nbuttons; i++) { 237 struct gpio_button_data *bdata = &ddata->data[i]; 238 239 if (bdata->button->type != type) 240 continue; 241 242 if (test_bit(bdata->button->code, bits)) 243 gpio_keys_disable_button(bdata); 244 else 245 gpio_keys_enable_button(bdata); 246 } 247 248 mutex_unlock(&ddata->disable_lock); 249 250 out: 251 kfree(bits); 252 return error; 253 } 254 255 #define ATTR_SHOW_FN(name, type, only_disabled) \ 256 static ssize_t gpio_keys_show_##name(struct device *dev, \ 257 struct device_attribute *attr, \ 258 char *buf) \ 259 { \ 260 struct platform_device *pdev = to_platform_device(dev); \ 261 struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \ 262 \ 263 return gpio_keys_attr_show_helper(ddata, buf, \ 264 type, only_disabled); \ 265 } 266 267 ATTR_SHOW_FN(keys, EV_KEY, false); 268 ATTR_SHOW_FN(switches, EV_SW, false); 269 ATTR_SHOW_FN(disabled_keys, EV_KEY, true); 270 ATTR_SHOW_FN(disabled_switches, EV_SW, true); 271 272 /* 273 * ATTRIBUTES: 274 * 275 * /sys/devices/platform/gpio-keys/keys [ro] 276 * /sys/devices/platform/gpio-keys/switches [ro] 277 */ 278 static DEVICE_ATTR(keys, S_IRUGO, gpio_keys_show_keys, NULL); 279 static DEVICE_ATTR(switches, S_IRUGO, gpio_keys_show_switches, NULL); 280 281 #define ATTR_STORE_FN(name, type) \ 282 static ssize_t gpio_keys_store_##name(struct device *dev, \ 283 struct device_attribute *attr, \ 284 const char *buf, \ 285 size_t count) \ 286 { \ 287 struct platform_device *pdev = to_platform_device(dev); \ 288 struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \ 289 ssize_t error; \ 290 \ 291 error = gpio_keys_attr_store_helper(ddata, buf, type); \ 292 if (error) \ 293 return error; \ 294 \ 295 return count; \ 296 } 297 298 ATTR_STORE_FN(disabled_keys, EV_KEY); 299 ATTR_STORE_FN(disabled_switches, EV_SW); 300 301 /* 302 * ATTRIBUTES: 303 * 304 * /sys/devices/platform/gpio-keys/disabled_keys [rw] 305 * /sys/devices/platform/gpio-keys/disables_switches [rw] 306 */ 307 static DEVICE_ATTR(disabled_keys, S_IWUSR | S_IRUGO, 308 gpio_keys_show_disabled_keys, 309 gpio_keys_store_disabled_keys); 310 static DEVICE_ATTR(disabled_switches, S_IWUSR | S_IRUGO, 311 gpio_keys_show_disabled_switches, 312 gpio_keys_store_disabled_switches); 313 314 static struct attribute *gpio_keys_attrs[] = { 315 &dev_attr_keys.attr, 316 &dev_attr_switches.attr, 317 &dev_attr_disabled_keys.attr, 318 &dev_attr_disabled_switches.attr, 319 NULL, 320 }; 321 322 static struct attribute_group gpio_keys_attr_group = { 323 .attrs = gpio_keys_attrs, 324 }; 325 326 static void gpio_keys_gpio_report_event(struct gpio_button_data *bdata) 327 { 328 const struct gpio_keys_button *button = bdata->button; 329 struct input_dev *input = bdata->input; 330 unsigned int type = button->type ?: EV_KEY; 331 int state = (gpio_get_value_cansleep(button->gpio) ? 1 : 0) ^ button->active_low; 332 333 if (type == EV_ABS) { 334 if (state) 335 input_event(input, type, button->code, button->value); 336 } else { 337 input_event(input, type, button->code, !!state); 338 } 339 input_sync(input); 340 } 341 342 static void gpio_keys_gpio_work_func(struct work_struct *work) 343 { 344 struct gpio_button_data *bdata = 345 container_of(work, struct gpio_button_data, work); 346 347 gpio_keys_gpio_report_event(bdata); 348 349 if (bdata->button->wakeup) 350 pm_relax(bdata->input->dev.parent); 351 } 352 353 static void gpio_keys_gpio_timer(unsigned long _data) 354 { 355 struct gpio_button_data *bdata = (struct gpio_button_data *)_data; 356 357 schedule_work(&bdata->work); 358 } 359 360 static irqreturn_t gpio_keys_gpio_isr(int irq, void *dev_id) 361 { 362 struct gpio_button_data *bdata = dev_id; 363 364 BUG_ON(irq != bdata->irq); 365 366 if (bdata->button->wakeup) 367 pm_stay_awake(bdata->input->dev.parent); 368 if (bdata->timer_debounce) 369 mod_timer(&bdata->timer, 370 jiffies + msecs_to_jiffies(bdata->timer_debounce)); 371 else 372 schedule_work(&bdata->work); 373 374 return IRQ_HANDLED; 375 } 376 377 static void gpio_keys_irq_timer(unsigned long _data) 378 { 379 struct gpio_button_data *bdata = (struct gpio_button_data *)_data; 380 struct input_dev *input = bdata->input; 381 unsigned long flags; 382 383 spin_lock_irqsave(&bdata->lock, flags); 384 if (bdata->key_pressed) { 385 input_event(input, EV_KEY, bdata->button->code, 0); 386 input_sync(input); 387 bdata->key_pressed = false; 388 } 389 spin_unlock_irqrestore(&bdata->lock, flags); 390 } 391 392 static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id) 393 { 394 struct gpio_button_data *bdata = dev_id; 395 const struct gpio_keys_button *button = bdata->button; 396 struct input_dev *input = bdata->input; 397 unsigned long flags; 398 399 BUG_ON(irq != bdata->irq); 400 401 spin_lock_irqsave(&bdata->lock, flags); 402 403 if (!bdata->key_pressed) { 404 if (bdata->button->wakeup) 405 pm_wakeup_event(bdata->input->dev.parent, 0); 406 407 input_event(input, EV_KEY, button->code, 1); 408 input_sync(input); 409 410 if (!bdata->timer_debounce) { 411 input_event(input, EV_KEY, button->code, 0); 412 input_sync(input); 413 goto out; 414 } 415 416 bdata->key_pressed = true; 417 } 418 419 if (bdata->timer_debounce) 420 mod_timer(&bdata->timer, 421 jiffies + msecs_to_jiffies(bdata->timer_debounce)); 422 out: 423 spin_unlock_irqrestore(&bdata->lock, flags); 424 return IRQ_HANDLED; 425 } 426 427 static void gpio_keys_quiesce_key(void *data) 428 { 429 struct gpio_button_data *bdata = data; 430 431 if (bdata->timer_debounce) 432 del_timer_sync(&bdata->timer); 433 434 cancel_work_sync(&bdata->work); 435 } 436 437 static int gpio_keys_setup_key(struct platform_device *pdev, 438 struct input_dev *input, 439 struct gpio_button_data *bdata, 440 const struct gpio_keys_button *button) 441 { 442 const char *desc = button->desc ? button->desc : "gpio_keys"; 443 struct device *dev = &pdev->dev; 444 irq_handler_t isr; 445 unsigned long irqflags; 446 int irq; 447 int error; 448 449 bdata->input = input; 450 bdata->button = button; 451 spin_lock_init(&bdata->lock); 452 453 if (gpio_is_valid(button->gpio)) { 454 455 error = devm_gpio_request_one(&pdev->dev, button->gpio, 456 GPIOF_IN, desc); 457 if (error < 0) { 458 dev_err(dev, "Failed to request GPIO %d, error %d\n", 459 button->gpio, error); 460 return error; 461 } 462 463 if (button->debounce_interval) { 464 error = gpio_set_debounce(button->gpio, 465 button->debounce_interval * 1000); 466 /* use timer if gpiolib doesn't provide debounce */ 467 if (error < 0) 468 bdata->timer_debounce = 469 button->debounce_interval; 470 } 471 472 irq = gpio_to_irq(button->gpio); 473 if (irq < 0) { 474 error = irq; 475 dev_err(dev, 476 "Unable to get irq number for GPIO %d, error %d\n", 477 button->gpio, error); 478 return error; 479 } 480 bdata->irq = irq; 481 482 INIT_WORK(&bdata->work, gpio_keys_gpio_work_func); 483 setup_timer(&bdata->timer, 484 gpio_keys_gpio_timer, (unsigned long)bdata); 485 486 isr = gpio_keys_gpio_isr; 487 irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING; 488 489 } else { 490 if (!button->irq) { 491 dev_err(dev, "No IRQ specified\n"); 492 return -EINVAL; 493 } 494 bdata->irq = button->irq; 495 496 if (button->type && button->type != EV_KEY) { 497 dev_err(dev, "Only EV_KEY allowed for IRQ buttons.\n"); 498 return -EINVAL; 499 } 500 501 bdata->timer_debounce = button->debounce_interval; 502 setup_timer(&bdata->timer, 503 gpio_keys_irq_timer, (unsigned long)bdata); 504 505 isr = gpio_keys_irq_isr; 506 irqflags = 0; 507 } 508 509 input_set_capability(input, button->type ?: EV_KEY, button->code); 510 511 /* 512 * Install custom action to cancel debounce timer and 513 * workqueue item. 514 */ 515 error = devm_add_action(&pdev->dev, gpio_keys_quiesce_key, bdata); 516 if (error) { 517 dev_err(&pdev->dev, 518 "failed to register quiesce action, error: %d\n", 519 error); 520 return error; 521 } 522 523 /* 524 * If platform has specified that the button can be disabled, 525 * we don't want it to share the interrupt line. 526 */ 527 if (!button->can_disable) 528 irqflags |= IRQF_SHARED; 529 530 error = devm_request_any_context_irq(&pdev->dev, bdata->irq, 531 isr, irqflags, desc, bdata); 532 if (error < 0) { 533 dev_err(dev, "Unable to claim irq %d; error %d\n", 534 bdata->irq, error); 535 return error; 536 } 537 538 return 0; 539 } 540 541 static void gpio_keys_report_state(struct gpio_keys_drvdata *ddata) 542 { 543 struct input_dev *input = ddata->input; 544 int i; 545 546 for (i = 0; i < ddata->pdata->nbuttons; i++) { 547 struct gpio_button_data *bdata = &ddata->data[i]; 548 if (gpio_is_valid(bdata->button->gpio)) 549 gpio_keys_gpio_report_event(bdata); 550 } 551 input_sync(input); 552 } 553 554 static int gpio_keys_open(struct input_dev *input) 555 { 556 struct gpio_keys_drvdata *ddata = input_get_drvdata(input); 557 const struct gpio_keys_platform_data *pdata = ddata->pdata; 558 int error; 559 560 if (pdata->enable) { 561 error = pdata->enable(input->dev.parent); 562 if (error) 563 return error; 564 } 565 566 /* Report current state of buttons that are connected to GPIOs */ 567 gpio_keys_report_state(ddata); 568 569 return 0; 570 } 571 572 static void gpio_keys_close(struct input_dev *input) 573 { 574 struct gpio_keys_drvdata *ddata = input_get_drvdata(input); 575 const struct gpio_keys_platform_data *pdata = ddata->pdata; 576 577 if (pdata->disable) 578 pdata->disable(input->dev.parent); 579 } 580 581 /* 582 * Handlers for alternative sources of platform_data 583 */ 584 585 #ifdef CONFIG_OF 586 /* 587 * Translate OpenFirmware node properties into platform_data 588 */ 589 static struct gpio_keys_platform_data * 590 gpio_keys_get_devtree_pdata(struct device *dev) 591 { 592 struct device_node *node, *pp; 593 struct gpio_keys_platform_data *pdata; 594 struct gpio_keys_button *button; 595 int error; 596 int nbuttons; 597 int i; 598 599 node = dev->of_node; 600 if (!node) 601 return ERR_PTR(-ENODEV); 602 603 nbuttons = of_get_child_count(node); 604 if (nbuttons == 0) 605 return ERR_PTR(-ENODEV); 606 607 pdata = devm_kzalloc(dev, 608 sizeof(*pdata) + nbuttons * sizeof(*button), 609 GFP_KERNEL); 610 if (!pdata) 611 return ERR_PTR(-ENOMEM); 612 613 pdata->buttons = (struct gpio_keys_button *)(pdata + 1); 614 pdata->nbuttons = nbuttons; 615 616 pdata->rep = !!of_get_property(node, "autorepeat", NULL); 617 618 i = 0; 619 for_each_child_of_node(node, pp) { 620 int gpio; 621 enum of_gpio_flags flags; 622 623 if (!of_find_property(pp, "gpios", NULL)) { 624 pdata->nbuttons--; 625 dev_warn(dev, "Found button without gpios\n"); 626 continue; 627 } 628 629 gpio = of_get_gpio_flags(pp, 0, &flags); 630 if (gpio < 0) { 631 error = gpio; 632 if (error != -EPROBE_DEFER) 633 dev_err(dev, 634 "Failed to get gpio flags, error: %d\n", 635 error); 636 return ERR_PTR(error); 637 } 638 639 button = &pdata->buttons[i++]; 640 641 button->gpio = gpio; 642 button->active_low = flags & OF_GPIO_ACTIVE_LOW; 643 644 if (of_property_read_u32(pp, "linux,code", &button->code)) { 645 dev_err(dev, "Button without keycode: 0x%x\n", 646 button->gpio); 647 return ERR_PTR(-EINVAL); 648 } 649 650 button->desc = of_get_property(pp, "label", NULL); 651 652 if (of_property_read_u32(pp, "linux,input-type", &button->type)) 653 button->type = EV_KEY; 654 655 button->wakeup = !!of_get_property(pp, "gpio-key,wakeup", NULL); 656 657 if (of_property_read_u32(pp, "debounce-interval", 658 &button->debounce_interval)) 659 button->debounce_interval = 5; 660 } 661 662 if (pdata->nbuttons == 0) 663 return ERR_PTR(-EINVAL); 664 665 return pdata; 666 } 667 668 static const struct of_device_id gpio_keys_of_match[] = { 669 { .compatible = "gpio-keys", }, 670 { }, 671 }; 672 MODULE_DEVICE_TABLE(of, gpio_keys_of_match); 673 674 #else 675 676 static inline struct gpio_keys_platform_data * 677 gpio_keys_get_devtree_pdata(struct device *dev) 678 { 679 return ERR_PTR(-ENODEV); 680 } 681 682 #endif 683 684 static int gpio_keys_probe(struct platform_device *pdev) 685 { 686 struct device *dev = &pdev->dev; 687 const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev); 688 struct gpio_keys_drvdata *ddata; 689 struct input_dev *input; 690 size_t size; 691 int i, error; 692 int wakeup = 0; 693 694 if (!pdata) { 695 pdata = gpio_keys_get_devtree_pdata(dev); 696 if (IS_ERR(pdata)) 697 return PTR_ERR(pdata); 698 } 699 700 size = sizeof(struct gpio_keys_drvdata) + 701 pdata->nbuttons * sizeof(struct gpio_button_data); 702 ddata = devm_kzalloc(dev, size, GFP_KERNEL); 703 if (!ddata) { 704 dev_err(dev, "failed to allocate state\n"); 705 return -ENOMEM; 706 } 707 708 input = devm_input_allocate_device(dev); 709 if (!input) { 710 dev_err(dev, "failed to allocate input device\n"); 711 return -ENOMEM; 712 } 713 714 ddata->pdata = pdata; 715 ddata->input = input; 716 mutex_init(&ddata->disable_lock); 717 718 platform_set_drvdata(pdev, ddata); 719 input_set_drvdata(input, ddata); 720 721 input->name = pdata->name ? : pdev->name; 722 input->phys = "gpio-keys/input0"; 723 input->dev.parent = &pdev->dev; 724 input->open = gpio_keys_open; 725 input->close = gpio_keys_close; 726 727 input->id.bustype = BUS_HOST; 728 input->id.vendor = 0x0001; 729 input->id.product = 0x0001; 730 input->id.version = 0x0100; 731 732 /* Enable auto repeat feature of Linux input subsystem */ 733 if (pdata->rep) 734 __set_bit(EV_REP, input->evbit); 735 736 for (i = 0; i < pdata->nbuttons; i++) { 737 const struct gpio_keys_button *button = &pdata->buttons[i]; 738 struct gpio_button_data *bdata = &ddata->data[i]; 739 740 error = gpio_keys_setup_key(pdev, input, bdata, button); 741 if (error) 742 return error; 743 744 if (button->wakeup) 745 wakeup = 1; 746 } 747 748 error = sysfs_create_group(&pdev->dev.kobj, &gpio_keys_attr_group); 749 if (error) { 750 dev_err(dev, "Unable to export keys/switches, error: %d\n", 751 error); 752 return error; 753 } 754 755 error = input_register_device(input); 756 if (error) { 757 dev_err(dev, "Unable to register input device, error: %d\n", 758 error); 759 goto err_remove_group; 760 } 761 762 device_init_wakeup(&pdev->dev, wakeup); 763 764 return 0; 765 766 err_remove_group: 767 sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group); 768 return error; 769 } 770 771 static int gpio_keys_remove(struct platform_device *pdev) 772 { 773 sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group); 774 775 device_init_wakeup(&pdev->dev, 0); 776 777 return 0; 778 } 779 780 #ifdef CONFIG_PM_SLEEP 781 static int gpio_keys_suspend(struct device *dev) 782 { 783 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); 784 struct input_dev *input = ddata->input; 785 int i; 786 787 if (device_may_wakeup(dev)) { 788 for (i = 0; i < ddata->pdata->nbuttons; i++) { 789 struct gpio_button_data *bdata = &ddata->data[i]; 790 if (bdata->button->wakeup) 791 enable_irq_wake(bdata->irq); 792 } 793 } else { 794 mutex_lock(&input->mutex); 795 if (input->users) 796 gpio_keys_close(input); 797 mutex_unlock(&input->mutex); 798 } 799 800 return 0; 801 } 802 803 static int gpio_keys_resume(struct device *dev) 804 { 805 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); 806 struct input_dev *input = ddata->input; 807 int error = 0; 808 int i; 809 810 if (device_may_wakeup(dev)) { 811 for (i = 0; i < ddata->pdata->nbuttons; i++) { 812 struct gpio_button_data *bdata = &ddata->data[i]; 813 if (bdata->button->wakeup) 814 disable_irq_wake(bdata->irq); 815 } 816 } else { 817 mutex_lock(&input->mutex); 818 if (input->users) 819 error = gpio_keys_open(input); 820 mutex_unlock(&input->mutex); 821 } 822 823 if (error) 824 return error; 825 826 gpio_keys_report_state(ddata); 827 return 0; 828 } 829 #endif 830 831 static SIMPLE_DEV_PM_OPS(gpio_keys_pm_ops, gpio_keys_suspend, gpio_keys_resume); 832 833 static struct platform_driver gpio_keys_device_driver = { 834 .probe = gpio_keys_probe, 835 .remove = gpio_keys_remove, 836 .driver = { 837 .name = "gpio-keys", 838 .owner = THIS_MODULE, 839 .pm = &gpio_keys_pm_ops, 840 .of_match_table = of_match_ptr(gpio_keys_of_match), 841 } 842 }; 843 844 static int __init gpio_keys_init(void) 845 { 846 return platform_driver_register(&gpio_keys_device_driver); 847 } 848 849 static void __exit gpio_keys_exit(void) 850 { 851 platform_driver_unregister(&gpio_keys_device_driver); 852 } 853 854 late_initcall(gpio_keys_init); 855 module_exit(gpio_keys_exit); 856 857 MODULE_LICENSE("GPL"); 858 MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>"); 859 MODULE_DESCRIPTION("Keyboard driver for GPIOs"); 860 MODULE_ALIAS("platform:gpio-keys"); 861