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/of_irq.h> 33 #include <linux/spinlock.h> 34 35 struct gpio_button_data { 36 const struct gpio_keys_button *button; 37 struct input_dev *input; 38 struct timer_list timer; 39 struct work_struct work; 40 unsigned int timer_debounce; /* in msecs */ 41 unsigned int irq; 42 spinlock_t lock; 43 bool disabled; 44 bool key_pressed; 45 }; 46 47 struct gpio_keys_drvdata { 48 const struct gpio_keys_platform_data *pdata; 49 struct input_dev *input; 50 struct mutex disable_lock; 51 struct gpio_button_data data[0]; 52 }; 53 54 /* 55 * SYSFS interface for enabling/disabling keys and switches: 56 * 57 * There are 4 attributes under /sys/devices/platform/gpio-keys/ 58 * keys [ro] - bitmap of keys (EV_KEY) which can be 59 * disabled 60 * switches [ro] - bitmap of switches (EV_SW) which can be 61 * disabled 62 * disabled_keys [rw] - bitmap of keys currently disabled 63 * disabled_switches [rw] - bitmap of switches currently disabled 64 * 65 * Userland can change these values and hence disable event generation 66 * for each key (or switch). Disabling a key means its interrupt line 67 * is disabled. 68 * 69 * For example, if we have following switches set up as gpio-keys: 70 * SW_DOCK = 5 71 * SW_CAMERA_LENS_COVER = 9 72 * SW_KEYPAD_SLIDE = 10 73 * SW_FRONT_PROXIMITY = 11 74 * This is read from switches: 75 * 11-9,5 76 * Next we want to disable proximity (11) and dock (5), we write: 77 * 11,5 78 * to file disabled_switches. Now proximity and dock IRQs are disabled. 79 * This can be verified by reading the file disabled_switches: 80 * 11,5 81 * If we now want to enable proximity (11) switch we write: 82 * 5 83 * to disabled_switches. 84 * 85 * We can disable only those keys which don't allow sharing the irq. 86 */ 87 88 /** 89 * get_n_events_by_type() - returns maximum number of events per @type 90 * @type: type of button (%EV_KEY, %EV_SW) 91 * 92 * Return value of this function can be used to allocate bitmap 93 * large enough to hold all bits for given type. 94 */ 95 static inline int get_n_events_by_type(int type) 96 { 97 BUG_ON(type != EV_SW && type != EV_KEY); 98 99 return (type == EV_KEY) ? KEY_CNT : SW_CNT; 100 } 101 102 /** 103 * gpio_keys_disable_button() - disables given GPIO button 104 * @bdata: button data for button to be disabled 105 * 106 * Disables button pointed by @bdata. This is done by masking 107 * IRQ line. After this function is called, button won't generate 108 * input events anymore. Note that one can only disable buttons 109 * that don't share IRQs. 110 * 111 * Make sure that @bdata->disable_lock is locked when entering 112 * this function to avoid races when concurrent threads are 113 * disabling buttons at the same time. 114 */ 115 static void gpio_keys_disable_button(struct gpio_button_data *bdata) 116 { 117 if (!bdata->disabled) { 118 /* 119 * Disable IRQ and possible debouncing timer. 120 */ 121 disable_irq(bdata->irq); 122 if (bdata->timer_debounce) 123 del_timer_sync(&bdata->timer); 124 125 bdata->disabled = true; 126 } 127 } 128 129 /** 130 * gpio_keys_enable_button() - enables given GPIO button 131 * @bdata: button data for button to be disabled 132 * 133 * Enables given button pointed by @bdata. 134 * 135 * Make sure that @bdata->disable_lock is locked when entering 136 * this function to avoid races with concurrent threads trying 137 * to enable the same button at the same time. 138 */ 139 static void gpio_keys_enable_button(struct gpio_button_data *bdata) 140 { 141 if (bdata->disabled) { 142 enable_irq(bdata->irq); 143 bdata->disabled = false; 144 } 145 } 146 147 /** 148 * gpio_keys_attr_show_helper() - fill in stringified bitmap of buttons 149 * @ddata: pointer to drvdata 150 * @buf: buffer where stringified bitmap is written 151 * @type: button type (%EV_KEY, %EV_SW) 152 * @only_disabled: does caller want only those buttons that are 153 * currently disabled or all buttons that can be 154 * disabled 155 * 156 * This function writes buttons that can be disabled to @buf. If 157 * @only_disabled is true, then @buf contains only those buttons 158 * that are currently disabled. Returns 0 on success or negative 159 * errno on failure. 160 */ 161 static ssize_t gpio_keys_attr_show_helper(struct gpio_keys_drvdata *ddata, 162 char *buf, unsigned int type, 163 bool only_disabled) 164 { 165 int n_events = get_n_events_by_type(type); 166 unsigned long *bits; 167 ssize_t ret; 168 int i; 169 170 bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL); 171 if (!bits) 172 return -ENOMEM; 173 174 for (i = 0; i < ddata->pdata->nbuttons; i++) { 175 struct gpio_button_data *bdata = &ddata->data[i]; 176 177 if (bdata->button->type != type) 178 continue; 179 180 if (only_disabled && !bdata->disabled) 181 continue; 182 183 __set_bit(bdata->button->code, bits); 184 } 185 186 ret = bitmap_scnlistprintf(buf, PAGE_SIZE - 2, bits, n_events); 187 buf[ret++] = '\n'; 188 buf[ret] = '\0'; 189 190 kfree(bits); 191 192 return ret; 193 } 194 195 /** 196 * gpio_keys_attr_store_helper() - enable/disable buttons based on given bitmap 197 * @ddata: pointer to drvdata 198 * @buf: buffer from userspace that contains stringified bitmap 199 * @type: button type (%EV_KEY, %EV_SW) 200 * 201 * This function parses stringified bitmap from @buf and disables/enables 202 * GPIO buttons accordingly. Returns 0 on success and negative error 203 * on failure. 204 */ 205 static ssize_t gpio_keys_attr_store_helper(struct gpio_keys_drvdata *ddata, 206 const char *buf, unsigned int type) 207 { 208 int n_events = get_n_events_by_type(type); 209 unsigned long *bits; 210 ssize_t error; 211 int i; 212 213 bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL); 214 if (!bits) 215 return -ENOMEM; 216 217 error = bitmap_parselist(buf, bits, n_events); 218 if (error) 219 goto out; 220 221 /* First validate */ 222 for (i = 0; i < ddata->pdata->nbuttons; i++) { 223 struct gpio_button_data *bdata = &ddata->data[i]; 224 225 if (bdata->button->type != type) 226 continue; 227 228 if (test_bit(bdata->button->code, bits) && 229 !bdata->button->can_disable) { 230 error = -EINVAL; 231 goto out; 232 } 233 } 234 235 mutex_lock(&ddata->disable_lock); 236 237 for (i = 0; i < ddata->pdata->nbuttons; i++) { 238 struct gpio_button_data *bdata = &ddata->data[i]; 239 240 if (bdata->button->type != type) 241 continue; 242 243 if (test_bit(bdata->button->code, bits)) 244 gpio_keys_disable_button(bdata); 245 else 246 gpio_keys_enable_button(bdata); 247 } 248 249 mutex_unlock(&ddata->disable_lock); 250 251 out: 252 kfree(bits); 253 return error; 254 } 255 256 #define ATTR_SHOW_FN(name, type, only_disabled) \ 257 static ssize_t gpio_keys_show_##name(struct device *dev, \ 258 struct device_attribute *attr, \ 259 char *buf) \ 260 { \ 261 struct platform_device *pdev = to_platform_device(dev); \ 262 struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \ 263 \ 264 return gpio_keys_attr_show_helper(ddata, buf, \ 265 type, only_disabled); \ 266 } 267 268 ATTR_SHOW_FN(keys, EV_KEY, false); 269 ATTR_SHOW_FN(switches, EV_SW, false); 270 ATTR_SHOW_FN(disabled_keys, EV_KEY, true); 271 ATTR_SHOW_FN(disabled_switches, EV_SW, true); 272 273 /* 274 * ATTRIBUTES: 275 * 276 * /sys/devices/platform/gpio-keys/keys [ro] 277 * /sys/devices/platform/gpio-keys/switches [ro] 278 */ 279 static DEVICE_ATTR(keys, S_IRUGO, gpio_keys_show_keys, NULL); 280 static DEVICE_ATTR(switches, S_IRUGO, gpio_keys_show_switches, NULL); 281 282 #define ATTR_STORE_FN(name, type) \ 283 static ssize_t gpio_keys_store_##name(struct device *dev, \ 284 struct device_attribute *attr, \ 285 const char *buf, \ 286 size_t count) \ 287 { \ 288 struct platform_device *pdev = to_platform_device(dev); \ 289 struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \ 290 ssize_t error; \ 291 \ 292 error = gpio_keys_attr_store_helper(ddata, buf, type); \ 293 if (error) \ 294 return error; \ 295 \ 296 return count; \ 297 } 298 299 ATTR_STORE_FN(disabled_keys, EV_KEY); 300 ATTR_STORE_FN(disabled_switches, EV_SW); 301 302 /* 303 * ATTRIBUTES: 304 * 305 * /sys/devices/platform/gpio-keys/disabled_keys [rw] 306 * /sys/devices/platform/gpio-keys/disables_switches [rw] 307 */ 308 static DEVICE_ATTR(disabled_keys, S_IWUSR | S_IRUGO, 309 gpio_keys_show_disabled_keys, 310 gpio_keys_store_disabled_keys); 311 static DEVICE_ATTR(disabled_switches, S_IWUSR | S_IRUGO, 312 gpio_keys_show_disabled_switches, 313 gpio_keys_store_disabled_switches); 314 315 static struct attribute *gpio_keys_attrs[] = { 316 &dev_attr_keys.attr, 317 &dev_attr_switches.attr, 318 &dev_attr_disabled_keys.attr, 319 &dev_attr_disabled_switches.attr, 320 NULL, 321 }; 322 323 static struct attribute_group gpio_keys_attr_group = { 324 .attrs = gpio_keys_attrs, 325 }; 326 327 static void gpio_keys_gpio_report_event(struct gpio_button_data *bdata) 328 { 329 const struct gpio_keys_button *button = bdata->button; 330 struct input_dev *input = bdata->input; 331 unsigned int type = button->type ?: EV_KEY; 332 int state = (gpio_get_value_cansleep(button->gpio) ? 1 : 0) ^ button->active_low; 333 334 if (type == EV_ABS) { 335 if (state) 336 input_event(input, type, button->code, button->value); 337 } else { 338 input_event(input, type, button->code, !!state); 339 } 340 input_sync(input); 341 } 342 343 static void gpio_keys_gpio_work_func(struct work_struct *work) 344 { 345 struct gpio_button_data *bdata = 346 container_of(work, struct gpio_button_data, work); 347 348 gpio_keys_gpio_report_event(bdata); 349 350 if (bdata->button->wakeup) 351 pm_relax(bdata->input->dev.parent); 352 } 353 354 static void gpio_keys_gpio_timer(unsigned long _data) 355 { 356 struct gpio_button_data *bdata = (struct gpio_button_data *)_data; 357 358 schedule_work(&bdata->work); 359 } 360 361 static irqreturn_t gpio_keys_gpio_isr(int irq, void *dev_id) 362 { 363 struct gpio_button_data *bdata = dev_id; 364 365 BUG_ON(irq != bdata->irq); 366 367 if (bdata->button->wakeup) 368 pm_stay_awake(bdata->input->dev.parent); 369 if (bdata->timer_debounce) 370 mod_timer(&bdata->timer, 371 jiffies + msecs_to_jiffies(bdata->timer_debounce)); 372 else 373 schedule_work(&bdata->work); 374 375 return IRQ_HANDLED; 376 } 377 378 static void gpio_keys_irq_timer(unsigned long _data) 379 { 380 struct gpio_button_data *bdata = (struct gpio_button_data *)_data; 381 struct input_dev *input = bdata->input; 382 unsigned long flags; 383 384 spin_lock_irqsave(&bdata->lock, flags); 385 if (bdata->key_pressed) { 386 input_event(input, EV_KEY, bdata->button->code, 0); 387 input_sync(input); 388 bdata->key_pressed = false; 389 } 390 spin_unlock_irqrestore(&bdata->lock, flags); 391 } 392 393 static irqreturn_t gpio_keys_irq_isr(int irq, void *dev_id) 394 { 395 struct gpio_button_data *bdata = dev_id; 396 const struct gpio_keys_button *button = bdata->button; 397 struct input_dev *input = bdata->input; 398 unsigned long flags; 399 400 BUG_ON(irq != bdata->irq); 401 402 spin_lock_irqsave(&bdata->lock, flags); 403 404 if (!bdata->key_pressed) { 405 if (bdata->button->wakeup) 406 pm_wakeup_event(bdata->input->dev.parent, 0); 407 408 input_event(input, EV_KEY, button->code, 1); 409 input_sync(input); 410 411 if (!bdata->timer_debounce) { 412 input_event(input, EV_KEY, button->code, 0); 413 input_sync(input); 414 goto out; 415 } 416 417 bdata->key_pressed = true; 418 } 419 420 if (bdata->timer_debounce) 421 mod_timer(&bdata->timer, 422 jiffies + msecs_to_jiffies(bdata->timer_debounce)); 423 out: 424 spin_unlock_irqrestore(&bdata->lock, flags); 425 return IRQ_HANDLED; 426 } 427 428 static void gpio_keys_quiesce_key(void *data) 429 { 430 struct gpio_button_data *bdata = data; 431 432 if (bdata->timer_debounce) 433 del_timer_sync(&bdata->timer); 434 435 cancel_work_sync(&bdata->work); 436 } 437 438 static int gpio_keys_setup_key(struct platform_device *pdev, 439 struct input_dev *input, 440 struct gpio_button_data *bdata, 441 const struct gpio_keys_button *button) 442 { 443 const char *desc = button->desc ? button->desc : "gpio_keys"; 444 struct device *dev = &pdev->dev; 445 irq_handler_t isr; 446 unsigned long irqflags; 447 int irq; 448 int error; 449 450 bdata->input = input; 451 bdata->button = button; 452 spin_lock_init(&bdata->lock); 453 454 if (gpio_is_valid(button->gpio)) { 455 456 error = devm_gpio_request_one(&pdev->dev, button->gpio, 457 GPIOF_IN, desc); 458 if (error < 0) { 459 dev_err(dev, "Failed to request GPIO %d, error %d\n", 460 button->gpio, error); 461 return error; 462 } 463 464 if (button->debounce_interval) { 465 error = gpio_set_debounce(button->gpio, 466 button->debounce_interval * 1000); 467 /* use timer if gpiolib doesn't provide debounce */ 468 if (error < 0) 469 bdata->timer_debounce = 470 button->debounce_interval; 471 } 472 473 irq = gpio_to_irq(button->gpio); 474 if (irq < 0) { 475 error = irq; 476 dev_err(dev, 477 "Unable to get irq number for GPIO %d, error %d\n", 478 button->gpio, error); 479 return error; 480 } 481 bdata->irq = irq; 482 483 INIT_WORK(&bdata->work, gpio_keys_gpio_work_func); 484 setup_timer(&bdata->timer, 485 gpio_keys_gpio_timer, (unsigned long)bdata); 486 487 isr = gpio_keys_gpio_isr; 488 irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING; 489 490 } else { 491 if (!button->irq) { 492 dev_err(dev, "No IRQ specified\n"); 493 return -EINVAL; 494 } 495 bdata->irq = button->irq; 496 497 if (button->type && button->type != EV_KEY) { 498 dev_err(dev, "Only EV_KEY allowed for IRQ buttons.\n"); 499 return -EINVAL; 500 } 501 502 bdata->timer_debounce = button->debounce_interval; 503 setup_timer(&bdata->timer, 504 gpio_keys_irq_timer, (unsigned long)bdata); 505 506 isr = gpio_keys_irq_isr; 507 irqflags = 0; 508 } 509 510 input_set_capability(input, button->type ?: EV_KEY, button->code); 511 512 /* 513 * Install custom action to cancel debounce timer and 514 * workqueue item. 515 */ 516 error = devm_add_action(&pdev->dev, gpio_keys_quiesce_key, bdata); 517 if (error) { 518 dev_err(&pdev->dev, 519 "failed to register quiesce action, error: %d\n", 520 error); 521 return error; 522 } 523 524 /* 525 * If platform has specified that the button can be disabled, 526 * we don't want it to share the interrupt line. 527 */ 528 if (!button->can_disable) 529 irqflags |= IRQF_SHARED; 530 531 error = devm_request_any_context_irq(&pdev->dev, bdata->irq, 532 isr, irqflags, desc, bdata); 533 if (error < 0) { 534 dev_err(dev, "Unable to claim irq %d; error %d\n", 535 bdata->irq, error); 536 return error; 537 } 538 539 return 0; 540 } 541 542 static void gpio_keys_report_state(struct gpio_keys_drvdata *ddata) 543 { 544 struct input_dev *input = ddata->input; 545 int i; 546 547 for (i = 0; i < ddata->pdata->nbuttons; i++) { 548 struct gpio_button_data *bdata = &ddata->data[i]; 549 if (gpio_is_valid(bdata->button->gpio)) 550 gpio_keys_gpio_report_event(bdata); 551 } 552 input_sync(input); 553 } 554 555 static int gpio_keys_open(struct input_dev *input) 556 { 557 struct gpio_keys_drvdata *ddata = input_get_drvdata(input); 558 const struct gpio_keys_platform_data *pdata = ddata->pdata; 559 int error; 560 561 if (pdata->enable) { 562 error = pdata->enable(input->dev.parent); 563 if (error) 564 return error; 565 } 566 567 /* Report current state of buttons that are connected to GPIOs */ 568 gpio_keys_report_state(ddata); 569 570 return 0; 571 } 572 573 static void gpio_keys_close(struct input_dev *input) 574 { 575 struct gpio_keys_drvdata *ddata = input_get_drvdata(input); 576 const struct gpio_keys_platform_data *pdata = ddata->pdata; 577 578 if (pdata->disable) 579 pdata->disable(input->dev.parent); 580 } 581 582 /* 583 * Handlers for alternative sources of platform_data 584 */ 585 586 #ifdef CONFIG_OF 587 /* 588 * Translate OpenFirmware node properties into platform_data 589 */ 590 static struct gpio_keys_platform_data * 591 gpio_keys_get_devtree_pdata(struct device *dev) 592 { 593 struct device_node *node, *pp; 594 struct gpio_keys_platform_data *pdata; 595 struct gpio_keys_button *button; 596 int error; 597 int nbuttons; 598 int i; 599 600 node = dev->of_node; 601 if (!node) 602 return ERR_PTR(-ENODEV); 603 604 nbuttons = of_get_child_count(node); 605 if (nbuttons == 0) 606 return ERR_PTR(-ENODEV); 607 608 pdata = devm_kzalloc(dev, 609 sizeof(*pdata) + nbuttons * sizeof(*button), 610 GFP_KERNEL); 611 if (!pdata) 612 return ERR_PTR(-ENOMEM); 613 614 pdata->buttons = (struct gpio_keys_button *)(pdata + 1); 615 pdata->nbuttons = nbuttons; 616 617 pdata->rep = !!of_get_property(node, "autorepeat", NULL); 618 619 i = 0; 620 for_each_child_of_node(node, pp) { 621 int gpio = -1; 622 enum of_gpio_flags flags; 623 624 button = &pdata->buttons[i++]; 625 626 if (!of_find_property(pp, "gpios", NULL)) { 627 button->irq = irq_of_parse_and_map(pp, 0); 628 if (button->irq == 0) { 629 i--; 630 pdata->nbuttons--; 631 dev_warn(dev, "Found button without gpios or irqs\n"); 632 continue; 633 } 634 } else { 635 gpio = of_get_gpio_flags(pp, 0, &flags); 636 if (gpio < 0) { 637 error = gpio; 638 if (error != -EPROBE_DEFER) 639 dev_err(dev, 640 "Failed to get gpio flags, error: %d\n", 641 error); 642 return ERR_PTR(error); 643 } 644 } 645 646 button->gpio = gpio; 647 button->active_low = flags & OF_GPIO_ACTIVE_LOW; 648 649 if (of_property_read_u32(pp, "linux,code", &button->code)) { 650 dev_err(dev, "Button without keycode: 0x%x\n", 651 button->gpio); 652 return ERR_PTR(-EINVAL); 653 } 654 655 button->desc = of_get_property(pp, "label", NULL); 656 657 if (of_property_read_u32(pp, "linux,input-type", &button->type)) 658 button->type = EV_KEY; 659 660 button->wakeup = !!of_get_property(pp, "gpio-key,wakeup", NULL); 661 662 if (of_property_read_u32(pp, "debounce-interval", 663 &button->debounce_interval)) 664 button->debounce_interval = 5; 665 } 666 667 if (pdata->nbuttons == 0) 668 return ERR_PTR(-EINVAL); 669 670 return pdata; 671 } 672 673 static const struct of_device_id gpio_keys_of_match[] = { 674 { .compatible = "gpio-keys", }, 675 { }, 676 }; 677 MODULE_DEVICE_TABLE(of, gpio_keys_of_match); 678 679 #else 680 681 static inline struct gpio_keys_platform_data * 682 gpio_keys_get_devtree_pdata(struct device *dev) 683 { 684 return ERR_PTR(-ENODEV); 685 } 686 687 #endif 688 689 static int gpio_keys_probe(struct platform_device *pdev) 690 { 691 struct device *dev = &pdev->dev; 692 const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev); 693 struct gpio_keys_drvdata *ddata; 694 struct input_dev *input; 695 size_t size; 696 int i, error; 697 int wakeup = 0; 698 699 if (!pdata) { 700 pdata = gpio_keys_get_devtree_pdata(dev); 701 if (IS_ERR(pdata)) 702 return PTR_ERR(pdata); 703 } 704 705 size = sizeof(struct gpio_keys_drvdata) + 706 pdata->nbuttons * sizeof(struct gpio_button_data); 707 ddata = devm_kzalloc(dev, size, GFP_KERNEL); 708 if (!ddata) { 709 dev_err(dev, "failed to allocate state\n"); 710 return -ENOMEM; 711 } 712 713 input = devm_input_allocate_device(dev); 714 if (!input) { 715 dev_err(dev, "failed to allocate input device\n"); 716 return -ENOMEM; 717 } 718 719 ddata->pdata = pdata; 720 ddata->input = input; 721 mutex_init(&ddata->disable_lock); 722 723 platform_set_drvdata(pdev, ddata); 724 input_set_drvdata(input, ddata); 725 726 input->name = pdata->name ? : pdev->name; 727 input->phys = "gpio-keys/input0"; 728 input->dev.parent = &pdev->dev; 729 input->open = gpio_keys_open; 730 input->close = gpio_keys_close; 731 732 input->id.bustype = BUS_HOST; 733 input->id.vendor = 0x0001; 734 input->id.product = 0x0001; 735 input->id.version = 0x0100; 736 737 /* Enable auto repeat feature of Linux input subsystem */ 738 if (pdata->rep) 739 __set_bit(EV_REP, input->evbit); 740 741 for (i = 0; i < pdata->nbuttons; i++) { 742 const struct gpio_keys_button *button = &pdata->buttons[i]; 743 struct gpio_button_data *bdata = &ddata->data[i]; 744 745 error = gpio_keys_setup_key(pdev, input, bdata, button); 746 if (error) 747 return error; 748 749 if (button->wakeup) 750 wakeup = 1; 751 } 752 753 error = sysfs_create_group(&pdev->dev.kobj, &gpio_keys_attr_group); 754 if (error) { 755 dev_err(dev, "Unable to export keys/switches, error: %d\n", 756 error); 757 return error; 758 } 759 760 error = input_register_device(input); 761 if (error) { 762 dev_err(dev, "Unable to register input device, error: %d\n", 763 error); 764 goto err_remove_group; 765 } 766 767 device_init_wakeup(&pdev->dev, wakeup); 768 769 return 0; 770 771 err_remove_group: 772 sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group); 773 return error; 774 } 775 776 static int gpio_keys_remove(struct platform_device *pdev) 777 { 778 sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group); 779 780 device_init_wakeup(&pdev->dev, 0); 781 782 return 0; 783 } 784 785 #ifdef CONFIG_PM_SLEEP 786 static int gpio_keys_suspend(struct device *dev) 787 { 788 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); 789 struct input_dev *input = ddata->input; 790 int i; 791 792 if (device_may_wakeup(dev)) { 793 for (i = 0; i < ddata->pdata->nbuttons; i++) { 794 struct gpio_button_data *bdata = &ddata->data[i]; 795 if (bdata->button->wakeup) 796 enable_irq_wake(bdata->irq); 797 } 798 } else { 799 mutex_lock(&input->mutex); 800 if (input->users) 801 gpio_keys_close(input); 802 mutex_unlock(&input->mutex); 803 } 804 805 return 0; 806 } 807 808 static int gpio_keys_resume(struct device *dev) 809 { 810 struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev); 811 struct input_dev *input = ddata->input; 812 int error = 0; 813 int i; 814 815 if (device_may_wakeup(dev)) { 816 for (i = 0; i < ddata->pdata->nbuttons; i++) { 817 struct gpio_button_data *bdata = &ddata->data[i]; 818 if (bdata->button->wakeup) 819 disable_irq_wake(bdata->irq); 820 } 821 } else { 822 mutex_lock(&input->mutex); 823 if (input->users) 824 error = gpio_keys_open(input); 825 mutex_unlock(&input->mutex); 826 } 827 828 if (error) 829 return error; 830 831 gpio_keys_report_state(ddata); 832 return 0; 833 } 834 #endif 835 836 static SIMPLE_DEV_PM_OPS(gpio_keys_pm_ops, gpio_keys_suspend, gpio_keys_resume); 837 838 static struct platform_driver gpio_keys_device_driver = { 839 .probe = gpio_keys_probe, 840 .remove = gpio_keys_remove, 841 .driver = { 842 .name = "gpio-keys", 843 .pm = &gpio_keys_pm_ops, 844 .of_match_table = of_match_ptr(gpio_keys_of_match), 845 } 846 }; 847 848 static int __init gpio_keys_init(void) 849 { 850 return platform_driver_register(&gpio_keys_device_driver); 851 } 852 853 static void __exit gpio_keys_exit(void) 854 { 855 platform_driver_unregister(&gpio_keys_device_driver); 856 } 857 858 late_initcall(gpio_keys_init); 859 module_exit(gpio_keys_exit); 860 861 MODULE_LICENSE("GPL"); 862 MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>"); 863 MODULE_DESCRIPTION("Keyboard driver for GPIOs"); 864 MODULE_ALIAS("platform:gpio-keys"); 865