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 39 struct timer_list release_timer; 40 unsigned int release_delay; /* in msecs, for IRQ-only buttons */ 41 42 struct delayed_work work; 43 unsigned int software_debounce; /* in msecs, for GPIO-driven buttons */ 44 45 unsigned int irq; 46 spinlock_t lock; 47 bool disabled; 48 bool key_pressed; 49 }; 50 51 struct gpio_keys_drvdata { 52 const struct gpio_keys_platform_data *pdata; 53 struct input_dev *input; 54 struct mutex disable_lock; 55 struct gpio_button_data data[0]; 56 }; 57 58 /* 59 * SYSFS interface for enabling/disabling keys and switches: 60 * 61 * There are 4 attributes under /sys/devices/platform/gpio-keys/ 62 * keys [ro] - bitmap of keys (EV_KEY) which can be 63 * disabled 64 * switches [ro] - bitmap of switches (EV_SW) which can be 65 * disabled 66 * disabled_keys [rw] - bitmap of keys currently disabled 67 * disabled_switches [rw] - bitmap of switches currently disabled 68 * 69 * Userland can change these values and hence disable event generation 70 * for each key (or switch). Disabling a key means its interrupt line 71 * is disabled. 72 * 73 * For example, if we have following switches set up as gpio-keys: 74 * SW_DOCK = 5 75 * SW_CAMERA_LENS_COVER = 9 76 * SW_KEYPAD_SLIDE = 10 77 * SW_FRONT_PROXIMITY = 11 78 * This is read from switches: 79 * 11-9,5 80 * Next we want to disable proximity (11) and dock (5), we write: 81 * 11,5 82 * to file disabled_switches. Now proximity and dock IRQs are disabled. 83 * This can be verified by reading the file disabled_switches: 84 * 11,5 85 * If we now want to enable proximity (11) switch we write: 86 * 5 87 * to disabled_switches. 88 * 89 * We can disable only those keys which don't allow sharing the irq. 90 */ 91 92 /** 93 * get_n_events_by_type() - returns maximum number of events per @type 94 * @type: type of button (%EV_KEY, %EV_SW) 95 * 96 * Return value of this function can be used to allocate bitmap 97 * large enough to hold all bits for given type. 98 */ 99 static inline int get_n_events_by_type(int type) 100 { 101 BUG_ON(type != EV_SW && type != EV_KEY); 102 103 return (type == EV_KEY) ? KEY_CNT : SW_CNT; 104 } 105 106 /** 107 * gpio_keys_disable_button() - disables given GPIO button 108 * @bdata: button data for button to be disabled 109 * 110 * Disables button pointed by @bdata. This is done by masking 111 * IRQ line. After this function is called, button won't generate 112 * input events anymore. Note that one can only disable buttons 113 * that don't share IRQs. 114 * 115 * Make sure that @bdata->disable_lock is locked when entering 116 * this function to avoid races when concurrent threads are 117 * disabling buttons at the same time. 118 */ 119 static void gpio_keys_disable_button(struct gpio_button_data *bdata) 120 { 121 if (!bdata->disabled) { 122 /* 123 * Disable IRQ and associated timer/work structure. 124 */ 125 disable_irq(bdata->irq); 126 127 if (gpio_is_valid(bdata->button->gpio)) 128 cancel_delayed_work_sync(&bdata->work); 129 else 130 del_timer_sync(&bdata->release_timer); 131 132 bdata->disabled = true; 133 } 134 } 135 136 /** 137 * gpio_keys_enable_button() - enables given GPIO button 138 * @bdata: button data for button to be disabled 139 * 140 * Enables given button pointed by @bdata. 141 * 142 * Make sure that @bdata->disable_lock is locked when entering 143 * this function to avoid races with concurrent threads trying 144 * to enable the same button at the same time. 145 */ 146 static void gpio_keys_enable_button(struct gpio_button_data *bdata) 147 { 148 if (bdata->disabled) { 149 enable_irq(bdata->irq); 150 bdata->disabled = false; 151 } 152 } 153 154 /** 155 * gpio_keys_attr_show_helper() - fill in stringified bitmap of buttons 156 * @ddata: pointer to drvdata 157 * @buf: buffer where stringified bitmap is written 158 * @type: button type (%EV_KEY, %EV_SW) 159 * @only_disabled: does caller want only those buttons that are 160 * currently disabled or all buttons that can be 161 * disabled 162 * 163 * This function writes buttons that can be disabled to @buf. If 164 * @only_disabled is true, then @buf contains only those buttons 165 * that are currently disabled. Returns 0 on success or negative 166 * errno on failure. 167 */ 168 static ssize_t gpio_keys_attr_show_helper(struct gpio_keys_drvdata *ddata, 169 char *buf, unsigned int type, 170 bool only_disabled) 171 { 172 int n_events = get_n_events_by_type(type); 173 unsigned long *bits; 174 ssize_t ret; 175 int i; 176 177 bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL); 178 if (!bits) 179 return -ENOMEM; 180 181 for (i = 0; i < ddata->pdata->nbuttons; i++) { 182 struct gpio_button_data *bdata = &ddata->data[i]; 183 184 if (bdata->button->type != type) 185 continue; 186 187 if (only_disabled && !bdata->disabled) 188 continue; 189 190 __set_bit(bdata->button->code, bits); 191 } 192 193 ret = bitmap_scnlistprintf(buf, PAGE_SIZE - 2, bits, n_events); 194 buf[ret++] = '\n'; 195 buf[ret] = '\0'; 196 197 kfree(bits); 198 199 return ret; 200 } 201 202 /** 203 * gpio_keys_attr_store_helper() - enable/disable buttons based on given bitmap 204 * @ddata: pointer to drvdata 205 * @buf: buffer from userspace that contains stringified bitmap 206 * @type: button type (%EV_KEY, %EV_SW) 207 * 208 * This function parses stringified bitmap from @buf and disables/enables 209 * GPIO buttons accordingly. Returns 0 on success and negative error 210 * on failure. 211 */ 212 static ssize_t gpio_keys_attr_store_helper(struct gpio_keys_drvdata *ddata, 213 const char *buf, unsigned int type) 214 { 215 int n_events = get_n_events_by_type(type); 216 unsigned long *bits; 217 ssize_t error; 218 int i; 219 220 bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL); 221 if (!bits) 222 return -ENOMEM; 223 224 error = bitmap_parselist(buf, bits, n_events); 225 if (error) 226 goto out; 227 228 /* First validate */ 229 for (i = 0; i < ddata->pdata->nbuttons; i++) { 230 struct gpio_button_data *bdata = &ddata->data[i]; 231 232 if (bdata->button->type != type) 233 continue; 234 235 if (test_bit(bdata->button->code, bits) && 236 !bdata->button->can_disable) { 237 error = -EINVAL; 238 goto out; 239 } 240 } 241 242 mutex_lock(&ddata->disable_lock); 243 244 for (i = 0; i < ddata->pdata->nbuttons; i++) { 245 struct gpio_button_data *bdata = &ddata->data[i]; 246 247 if (bdata->button->type != type) 248 continue; 249 250 if (test_bit(bdata->button->code, bits)) 251 gpio_keys_disable_button(bdata); 252 else 253 gpio_keys_enable_button(bdata); 254 } 255 256 mutex_unlock(&ddata->disable_lock); 257 258 out: 259 kfree(bits); 260 return error; 261 } 262 263 #define ATTR_SHOW_FN(name, type, only_disabled) \ 264 static ssize_t gpio_keys_show_##name(struct device *dev, \ 265 struct device_attribute *attr, \ 266 char *buf) \ 267 { \ 268 struct platform_device *pdev = to_platform_device(dev); \ 269 struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \ 270 \ 271 return gpio_keys_attr_show_helper(ddata, buf, \ 272 type, only_disabled); \ 273 } 274 275 ATTR_SHOW_FN(keys, EV_KEY, false); 276 ATTR_SHOW_FN(switches, EV_SW, false); 277 ATTR_SHOW_FN(disabled_keys, EV_KEY, true); 278 ATTR_SHOW_FN(disabled_switches, EV_SW, true); 279 280 /* 281 * ATTRIBUTES: 282 * 283 * /sys/devices/platform/gpio-keys/keys [ro] 284 * /sys/devices/platform/gpio-keys/switches [ro] 285 */ 286 static DEVICE_ATTR(keys, S_IRUGO, gpio_keys_show_keys, NULL); 287 static DEVICE_ATTR(switches, S_IRUGO, gpio_keys_show_switches, NULL); 288 289 #define ATTR_STORE_FN(name, type) \ 290 static ssize_t gpio_keys_store_##name(struct device *dev, \ 291 struct device_attribute *attr, \ 292 const char *buf, \ 293 size_t count) \ 294 { \ 295 struct platform_device *pdev = to_platform_device(dev); \ 296 struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \ 297 ssize_t error; \ 298 \ 299 error = gpio_keys_attr_store_helper(ddata, buf, type); \ 300 if (error) \ 301 return error; \ 302 \ 303 return count; \ 304 } 305 306 ATTR_STORE_FN(disabled_keys, EV_KEY); 307 ATTR_STORE_FN(disabled_switches, EV_SW); 308 309 /* 310 * ATTRIBUTES: 311 * 312 * /sys/devices/platform/gpio-keys/disabled_keys [rw] 313 * /sys/devices/platform/gpio-keys/disables_switches [rw] 314 */ 315 static DEVICE_ATTR(disabled_keys, S_IWUSR | S_IRUGO, 316 gpio_keys_show_disabled_keys, 317 gpio_keys_store_disabled_keys); 318 static DEVICE_ATTR(disabled_switches, S_IWUSR | S_IRUGO, 319 gpio_keys_show_disabled_switches, 320 gpio_keys_store_disabled_switches); 321 322 static struct attribute *gpio_keys_attrs[] = { 323 &dev_attr_keys.attr, 324 &dev_attr_switches.attr, 325 &dev_attr_disabled_keys.attr, 326 &dev_attr_disabled_switches.attr, 327 NULL, 328 }; 329 330 static struct attribute_group gpio_keys_attr_group = { 331 .attrs = gpio_keys_attrs, 332 }; 333 334 static void gpio_keys_gpio_report_event(struct gpio_button_data *bdata) 335 { 336 const struct gpio_keys_button *button = bdata->button; 337 struct input_dev *input = bdata->input; 338 unsigned int type = button->type ?: EV_KEY; 339 int state = (gpio_get_value_cansleep(button->gpio) ? 1 : 0) ^ button->active_low; 340 341 if (type == EV_ABS) { 342 if (state) 343 input_event(input, type, button->code, button->value); 344 } else { 345 input_event(input, type, button->code, !!state); 346 } 347 input_sync(input); 348 } 349 350 static void gpio_keys_gpio_work_func(struct work_struct *work) 351 { 352 struct gpio_button_data *bdata = 353 container_of(work, struct gpio_button_data, work.work); 354 355 gpio_keys_gpio_report_event(bdata); 356 357 if (bdata->button->wakeup) 358 pm_relax(bdata->input->dev.parent); 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); 369 370 mod_delayed_work(system_wq, 371 &bdata->work, 372 msecs_to_jiffies(bdata->software_debounce)); 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->release_delay) { 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->release_delay) 420 mod_timer(&bdata->release_timer, 421 jiffies + msecs_to_jiffies(bdata->release_delay)); 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 (gpio_is_valid(bdata->button->gpio)) 432 cancel_delayed_work_sync(&bdata->work); 433 else 434 del_timer_sync(&bdata->release_timer); 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->software_debounce = 469 button->debounce_interval; 470 } 471 472 if (button->irq) { 473 bdata->irq = button->irq; 474 } else { 475 irq = gpio_to_irq(button->gpio); 476 if (irq < 0) { 477 error = irq; 478 dev_err(dev, 479 "Unable to get irq number for GPIO %d, error %d\n", 480 button->gpio, error); 481 return error; 482 } 483 bdata->irq = irq; 484 } 485 486 INIT_DELAYED_WORK(&bdata->work, gpio_keys_gpio_work_func); 487 488 isr = gpio_keys_gpio_isr; 489 irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING; 490 491 } else { 492 if (!button->irq) { 493 dev_err(dev, "No IRQ specified\n"); 494 return -EINVAL; 495 } 496 bdata->irq = button->irq; 497 498 if (button->type && button->type != EV_KEY) { 499 dev_err(dev, "Only EV_KEY allowed for IRQ buttons.\n"); 500 return -EINVAL; 501 } 502 503 bdata->release_delay = button->debounce_interval; 504 setup_timer(&bdata->release_timer, 505 gpio_keys_irq_timer, (unsigned long)bdata); 506 507 isr = gpio_keys_irq_isr; 508 irqflags = 0; 509 } 510 511 input_set_capability(input, button->type ?: EV_KEY, button->code); 512 513 /* 514 * Install custom action to cancel release timer and 515 * workqueue item. 516 */ 517 error = devm_add_action(&pdev->dev, gpio_keys_quiesce_key, bdata); 518 if (error) { 519 dev_err(&pdev->dev, 520 "failed to register quiesce action, error: %d\n", 521 error); 522 return error; 523 } 524 525 /* 526 * If platform has specified that the button can be disabled, 527 * we don't want it to share the interrupt line. 528 */ 529 if (!button->can_disable) 530 irqflags |= IRQF_SHARED; 531 532 error = devm_request_any_context_irq(&pdev->dev, bdata->irq, 533 isr, irqflags, desc, bdata); 534 if (error < 0) { 535 dev_err(dev, "Unable to claim irq %d; error %d\n", 536 bdata->irq, error); 537 return error; 538 } 539 540 return 0; 541 } 542 543 static void gpio_keys_report_state(struct gpio_keys_drvdata *ddata) 544 { 545 struct input_dev *input = ddata->input; 546 int i; 547 548 for (i = 0; i < ddata->pdata->nbuttons; i++) { 549 struct gpio_button_data *bdata = &ddata->data[i]; 550 if (gpio_is_valid(bdata->button->gpio)) 551 gpio_keys_gpio_report_event(bdata); 552 } 553 input_sync(input); 554 } 555 556 static int gpio_keys_open(struct input_dev *input) 557 { 558 struct gpio_keys_drvdata *ddata = input_get_drvdata(input); 559 const struct gpio_keys_platform_data *pdata = ddata->pdata; 560 int error; 561 562 if (pdata->enable) { 563 error = pdata->enable(input->dev.parent); 564 if (error) 565 return error; 566 } 567 568 /* Report current state of buttons that are connected to GPIOs */ 569 gpio_keys_report_state(ddata); 570 571 return 0; 572 } 573 574 static void gpio_keys_close(struct input_dev *input) 575 { 576 struct gpio_keys_drvdata *ddata = input_get_drvdata(input); 577 const struct gpio_keys_platform_data *pdata = ddata->pdata; 578 579 if (pdata->disable) 580 pdata->disable(input->dev.parent); 581 } 582 583 /* 584 * Handlers for alternative sources of platform_data 585 */ 586 587 #ifdef CONFIG_OF 588 /* 589 * Translate OpenFirmware node properties into platform_data 590 */ 591 static struct gpio_keys_platform_data * 592 gpio_keys_get_devtree_pdata(struct device *dev) 593 { 594 struct device_node *node, *pp; 595 struct gpio_keys_platform_data *pdata; 596 struct gpio_keys_button *button; 597 int error; 598 int nbuttons; 599 int i; 600 601 node = dev->of_node; 602 if (!node) 603 return ERR_PTR(-ENODEV); 604 605 nbuttons = of_get_child_count(node); 606 if (nbuttons == 0) 607 return ERR_PTR(-ENODEV); 608 609 pdata = devm_kzalloc(dev, 610 sizeof(*pdata) + nbuttons * sizeof(*button), 611 GFP_KERNEL); 612 if (!pdata) 613 return ERR_PTR(-ENOMEM); 614 615 pdata->buttons = (struct gpio_keys_button *)(pdata + 1); 616 pdata->nbuttons = nbuttons; 617 618 pdata->rep = !!of_get_property(node, "autorepeat", NULL); 619 620 i = 0; 621 for_each_child_of_node(node, pp) { 622 enum of_gpio_flags flags; 623 624 button = &pdata->buttons[i++]; 625 626 button->gpio = of_get_gpio_flags(pp, 0, &flags); 627 if (button->gpio < 0) { 628 error = button->gpio; 629 if (error != -ENOENT) { 630 if (error != -EPROBE_DEFER) 631 dev_err(dev, 632 "Failed to get gpio flags, error: %d\n", 633 error); 634 return ERR_PTR(error); 635 } 636 } else { 637 button->active_low = flags & OF_GPIO_ACTIVE_LOW; 638 } 639 640 button->irq = irq_of_parse_and_map(pp, 0); 641 642 if (!gpio_is_valid(button->gpio) && !button->irq) { 643 dev_err(dev, "Found button without gpios or irqs\n"); 644 return ERR_PTR(-EINVAL); 645 } 646 647 if (of_property_read_u32(pp, "linux,code", &button->code)) { 648 dev_err(dev, "Button without keycode: 0x%x\n", 649 button->gpio); 650 return ERR_PTR(-EINVAL); 651 } 652 653 button->desc = of_get_property(pp, "label", NULL); 654 655 if (of_property_read_u32(pp, "linux,input-type", &button->type)) 656 button->type = EV_KEY; 657 658 button->wakeup = !!of_get_property(pp, "gpio-key,wakeup", NULL); 659 660 button->can_disable = !!of_get_property(pp, "linux,can-disable", 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