drivers/input/keyboard/gpio_keys.c

   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_platform.h>
  30 #include <linux/of_gpio.h>
  31
  32 struct gpio_button_data {
  33         struct gpio_keys_button *button;
  34         struct input_dev *input;
  35         struct timer_list timer;
  36         struct work_struct work;
  37         int timer_debounce;     /* in msecs */
  38         bool disabled;
  39 };
  40
  41 struct gpio_keys_drvdata {
  42         struct input_dev *input;
  43         struct mutex disable_lock;
  44         unsigned int n_buttons;
  45         int (*enable)(struct device *dev);
  46         void (*disable)(struct device *dev);
  47         struct gpio_button_data data[0];
  48 };
  49
  50 /*
  51  * SYSFS interface for enabling/disabling keys and switches:
  52  *
  53  * There are 4 attributes under /sys/devices/platform/gpio-keys/
  54  *      keys [ro]              - bitmap of keys (EV_KEY) which can be
  55  *                               disabled
  56  *      switches [ro]          - bitmap of switches (EV_SW) which can be
  57  *                               disabled
  58  *      disabled_keys [rw]     - bitmap of keys currently disabled
  59  *      disabled_switches [rw] - bitmap of switches currently disabled
  60  *
  61  * Userland can change these values and hence disable event generation
  62  * for each key (or switch). Disabling a key means its interrupt line
  63  * is disabled.
  64  *
  65  * For example, if we have following switches set up as gpio-keys:
  66  *      SW_DOCK = 5
  67  *      SW_CAMERA_LENS_COVER = 9
  68  *      SW_KEYPAD_SLIDE = 10
  69  *      SW_FRONT_PROXIMITY = 11
  70  * This is read from switches:
  71  *      11-9,5
  72  * Next we want to disable proximity (11) and dock (5), we write:
  73  *      11,5
  74  * to file disabled_switches. Now proximity and dock IRQs are disabled.
  75  * This can be verified by reading the file disabled_switches:
  76  *      11,5
  77  * If we now want to enable proximity (11) switch we write:
  78  *      5
  79  * to disabled_switches.
  80  *
  81  * We can disable only those keys which don't allow sharing the irq.
  82  */
  83
  84 /**
  85  * get_n_events_by_type() - returns maximum number of events per @type
  86  * @type: type of button (%EV_KEY, %EV_SW)
  87  *
  88  * Return value of this function can be used to allocate bitmap
  89  * large enough to hold all bits for given type.
  90  */
  91 static inline int get_n_events_by_type(int type)
  92 {
  93         BUG_ON(type != EV_SW && type != EV_KEY);
  94
  95         return (type == EV_KEY) ? KEY_CNT : SW_CNT;
  96 }
  97
  98 /**
  99  * gpio_keys_disable_button() - disables given GPIO button
 100  * @bdata: button data for button to be disabled
 101  *
 102  * Disables button pointed by @bdata. This is done by masking
 103  * IRQ line. After this function is called, button won't generate
 104  * input events anymore. Note that one can only disable buttons
 105  * that don't share IRQs.
 106  *
 107  * Make sure that @bdata->disable_lock is locked when entering
 108  * this function to avoid races when concurrent threads are
 109  * disabling buttons at the same time.
 110  */
 111 static void gpio_keys_disable_button(struct gpio_button_data *bdata)
 112 {
 113         if (!bdata->disabled) {
 114                 /*
 115                  * Disable IRQ and possible debouncing timer.
 116                  */
 117                 disable_irq(gpio_to_irq(bdata->button->gpio));
 118                 if (bdata->timer_debounce)
 119                         del_timer_sync(&bdata->timer);
 120
 121                 bdata->disabled = true;
 122         }
 123 }
 124
 125 /**
 126  * gpio_keys_enable_button() - enables given GPIO button
 127  * @bdata: button data for button to be disabled
 128  *
 129  * Enables given button pointed by @bdata.
 130  *
 131  * Make sure that @bdata->disable_lock is locked when entering
 132  * this function to avoid races with concurrent threads trying
 133  * to enable the same button at the same time.
 134  */
 135 static void gpio_keys_enable_button(struct gpio_button_data *bdata)
 136 {
 137         if (bdata->disabled) {
 138                 enable_irq(gpio_to_irq(bdata->button->gpio));
 139                 bdata->disabled = false;
 140         }
 141 }
 142
 143 /**
 144  * gpio_keys_attr_show_helper() - fill in stringified bitmap of buttons
 145  * @ddata: pointer to drvdata
 146  * @buf: buffer where stringified bitmap is written
 147  * @type: button type (%EV_KEY, %EV_SW)
 148  * @only_disabled: does caller want only those buttons that are
 149  *                 currently disabled or all buttons that can be
 150  *                 disabled
 151  *
 152  * This function writes buttons that can be disabled to @buf. If
 153  * @only_disabled is true, then @buf contains only those buttons
 154  * that are currently disabled. Returns 0 on success or negative
 155  * errno on failure.
 156  */
 157 static ssize_t gpio_keys_attr_show_helper(struct gpio_keys_drvdata *ddata,
 158                                           char *buf, unsigned int type,
 159                                           bool only_disabled)
 160 {
 161         int n_events = get_n_events_by_type(type);
 162         unsigned long *bits;
 163         ssize_t ret;
 164         int i;
 165
 166         bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL);
 167         if (!bits)
 168                 return -ENOMEM;
 169
 170         for (i = 0; i < ddata->n_buttons; i++) {
 171                 struct gpio_button_data *bdata = &ddata->data[i];
 172
 173                 if (bdata->button->type != type)
 174                         continue;
 175
 176                 if (only_disabled && !bdata->disabled)
 177                         continue;
 178
 179                 __set_bit(bdata->button->code, bits);
 180         }
 181
 182         ret = bitmap_scnlistprintf(buf, PAGE_SIZE - 2, bits, n_events);
 183         buf[ret++] = '\n';
 184         buf[ret] = '\0';
 185
 186         kfree(bits);
 187
 188         return ret;
 189 }
 190
 191 /**
 192  * gpio_keys_attr_store_helper() - enable/disable buttons based on given bitmap
 193  * @ddata: pointer to drvdata
 194  * @buf: buffer from userspace that contains stringified bitmap
 195  * @type: button type (%EV_KEY, %EV_SW)
 196  *
 197  * This function parses stringified bitmap from @buf and disables/enables
 198  * GPIO buttons accordinly. Returns 0 on success and negative error
 199  * on failure.
 200  */
 201 static ssize_t gpio_keys_attr_store_helper(struct gpio_keys_drvdata *ddata,
 202                                            const char *buf, unsigned int type)
 203 {
 204         int n_events = get_n_events_by_type(type);
 205         unsigned long *bits;
 206         ssize_t error;
 207         int i;
 208
 209         bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL);
 210         if (!bits)
 211                 return -ENOMEM;
 212
 213         error = bitmap_parselist(buf, bits, n_events);
 214         if (error)
 215                 goto out;
 216
 217         /* First validate */
 218         for (i = 0; i < ddata->n_buttons; i++) {
 219                 struct gpio_button_data *bdata = &ddata->data[i];
 220
 221                 if (bdata->button->type != type)
 222                         continue;
 223
 224                 if (test_bit(bdata->button->code, bits) &&
 225                     !bdata->button->can_disable) {
 226                         error = -EINVAL;
 227                         goto out;
 228                 }
 229         }
 230
 231         mutex_lock(&ddata->disable_lock);
 232
 233         for (i = 0; i < ddata->n_buttons; i++) {
 234                 struct gpio_button_data *bdata = &ddata->data[i];
 235
 236                 if (bdata->button->type != type)
 237                         continue;
 238
 239                 if (test_bit(bdata->button->code, bits))
 240                         gpio_keys_disable_button(bdata);
 241                 else
 242                         gpio_keys_enable_button(bdata);
 243         }
 244
 245         mutex_unlock(&ddata->disable_lock);
 246
 247 out:
 248         kfree(bits);
 249         return error;
 250 }
 251
 252 #define ATTR_SHOW_FN(name, type, only_disabled)                         \
 253 static ssize_t gpio_keys_show_##name(struct device *dev,                \
 254                                      struct device_attribute *attr,     \
 255                                      char *buf)                         \
 256 {                                                                       \
 257         struct platform_device *pdev = to_platform_device(dev);         \
 258         struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);   \
 259                                                                         \
 260         return gpio_keys_attr_show_helper(ddata, buf,                   \
 261                                           type, only_disabled);         \
 262 }
 263
 264 ATTR_SHOW_FN(keys, EV_KEY, false);
 265 ATTR_SHOW_FN(switches, EV_SW, false);
 266 ATTR_SHOW_FN(disabled_keys, EV_KEY, true);
 267 ATTR_SHOW_FN(disabled_switches, EV_SW, true);
 268
 269 /*
 270  * ATTRIBUTES:
 271  *
 272  * /sys/devices/platform/gpio-keys/keys [ro]
 273  * /sys/devices/platform/gpio-keys/switches [ro]
 274  */
 275 static DEVICE_ATTR(keys, S_IRUGO, gpio_keys_show_keys, NULL);
 276 static DEVICE_ATTR(switches, S_IRUGO, gpio_keys_show_switches, NULL);
 277
 278 #define ATTR_STORE_FN(name, type)                                       \
 279 static ssize_t gpio_keys_store_##name(struct device *dev,               \
 280                                       struct device_attribute *attr,    \
 281                                       const char *buf,                  \
 282                                       size_t count)                     \
 283 {                                                                       \
 284         struct platform_device *pdev = to_platform_device(dev);         \
 285         struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);   \
 286         ssize_t error;                                                  \
 287                                                                         \
 288         error = gpio_keys_attr_store_helper(ddata, buf, type);          \
 289         if (error)                                                      \
 290                 return error;                                           \
 291                                                                         \
 292         return count;                                                   \
 293 }
 294
 295 ATTR_STORE_FN(disabled_keys, EV_KEY);
 296 ATTR_STORE_FN(disabled_switches, EV_SW);
 297
 298 /*
 299  * ATTRIBUTES:
 300  *
 301  * /sys/devices/platform/gpio-keys/disabled_keys [rw]
 302  * /sys/devices/platform/gpio-keys/disables_switches [rw]
 303  */
 304 static DEVICE_ATTR(disabled_keys, S_IWUSR | S_IRUGO,
 305                    gpio_keys_show_disabled_keys,
 306                    gpio_keys_store_disabled_keys);
 307 static DEVICE_ATTR(disabled_switches, S_IWUSR | S_IRUGO,
 308                    gpio_keys_show_disabled_switches,
 309                    gpio_keys_store_disabled_switches);
 310
 311 static struct attribute *gpio_keys_attrs[] = {
 312         &dev_attr_keys.attr,
 313         &dev_attr_switches.attr,
 314         &dev_attr_disabled_keys.attr,
 315         &dev_attr_disabled_switches.attr,
 316         NULL,
 317 };
 318
 319 static struct attribute_group gpio_keys_attr_group = {
 320         .attrs = gpio_keys_attrs,
 321 };
 322
 323 static void gpio_keys_report_event(struct gpio_button_data *bdata)
 324 {
 325         struct gpio_keys_button *button = bdata->button;
 326         struct input_dev *input = bdata->input;
 327         unsigned int type = button->type ?: EV_KEY;
 328         int state = (gpio_get_value_cansleep(button->gpio) ? 1 : 0) ^ button->active_low;
 329
 330         if (type == EV_ABS) {
 331                 if (state)
 332                         input_event(input, type, button->code, button->value);
 333         } else {
 334                 input_event(input, type, button->code, !!state);
 335         }
 336         input_sync(input);
 337 }
 338
 339 static void gpio_keys_work_func(struct work_struct *work)
 340 {
 341         struct gpio_button_data *bdata =
 342                 container_of(work, struct gpio_button_data, work);
 343
 344         gpio_keys_report_event(bdata);
 345 }
 346
 347 static void gpio_keys_timer(unsigned long _data)
 348 {
 349         struct gpio_button_data *data = (struct gpio_button_data *)_data;
 350
 351         schedule_work(&data->work);
 352 }
 353
 354 static irqreturn_t gpio_keys_isr(int irq, void *dev_id)
 355 {
 356         struct gpio_button_data *bdata = dev_id;
 357         struct gpio_keys_button *button = bdata->button;
 358
 359         BUG_ON(irq != gpio_to_irq(button->gpio));
 360
 361         if (bdata->timer_debounce)
 362                 mod_timer(&bdata->timer,
 363                         jiffies + msecs_to_jiffies(bdata->timer_debounce));
 364         else
 365                 schedule_work(&bdata->work);
 366
 367         return IRQ_HANDLED;
 368 }
 369
 370 static int __devinit gpio_keys_setup_key(struct platform_device *pdev,
 371                                          struct gpio_button_data *bdata,
 372                                          struct gpio_keys_button *button)
 373 {
 374         const char *desc = button->desc ? button->desc : "gpio_keys";
 375         struct device *dev = &pdev->dev;
 376         unsigned long irqflags;
 377         int irq, error;
 378
 379         setup_timer(&bdata->timer, gpio_keys_timer, (unsigned long)bdata);
 380         INIT_WORK(&bdata->work, gpio_keys_work_func);
 381
 382         error = gpio_request(button->gpio, desc);
 383         if (error < 0) {
 384                 dev_err(dev, "failed to request GPIO %d, error %d\n",
 385                         button->gpio, error);
 386                 goto fail2;
 387         }
 388
 389         error = gpio_direction_input(button->gpio);
 390         if (error < 0) {
 391                 dev_err(dev, "failed to configure"
 392                         " direction for GPIO %d, error %d\n",
 393                         button->gpio, error);
 394                 goto fail3;
 395         }
 396
 397         if (button->debounce_interval) {
 398                 error = gpio_set_debounce(button->gpio,
 399                                           button->debounce_interval * 1000);
 400                 /* use timer if gpiolib doesn't provide debounce */
 401                 if (error < 0)
 402                         bdata->timer_debounce = button->debounce_interval;
 403         }
 404
 405         irq = gpio_to_irq(button->gpio);
 406         if (irq < 0) {
 407                 error = irq;
 408                 dev_err(dev, "Unable to get irq number for GPIO %d, error %d\n",
 409                         button->gpio, error);
 410                 goto fail3;
 411         }
 412
 413         irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
 414         /*
 415          * If platform has specified that the button can be disabled,
 416          * we don't want it to share the interrupt line.
 417          */
 418         if (!button->can_disable)
 419                 irqflags |= IRQF_SHARED;
 420
 421         error = request_threaded_irq(irq, NULL, gpio_keys_isr, irqflags, desc, bdata);
 422         if (error < 0) {
 423                 dev_err(dev, "Unable to claim irq %d; error %d\n",
 424                         irq, error);
 425                 goto fail3;
 426         }
 427
 428         return 0;
 429
 430 fail3:
 431         gpio_free(button->gpio);
 432 fail2:
 433         return error;
 434 }
 435
 436 static int gpio_keys_open(struct input_dev *input)
 437 {
 438         struct gpio_keys_drvdata *ddata = input_get_drvdata(input);
 439
 440         return ddata->enable ? ddata->enable(input->dev.parent) : 0;
 441 }
 442
 443 static void gpio_keys_close(struct input_dev *input)
 444 {
 445         struct gpio_keys_drvdata *ddata = input_get_drvdata(input);
 446
 447         if (ddata->disable)
 448                 ddata->disable(input->dev.parent);
 449 }
 450
 451 /*
 452  * Handlers for alternative sources of platform_data
 453  */
 454 #ifdef CONFIG_OF
 455 /*
 456  * Translate OpenFirmware node properties into platform_data
 457  */
 458 static int gpio_keys_get_devtree_pdata(struct device *dev,
 459                             struct gpio_keys_platform_data *pdata)
 460 {
 461         struct device_node *node, *pp;
 462         int i;
 463         struct gpio_keys_button *buttons;
 464         u32 reg;
 465
 466         node = dev->of_node;
 467         if (node == NULL)
 468                 return -ENODEV;
 469
 470         memset(pdata, 0, sizeof *pdata);
 471
 472         pdata->rep = !!of_get_property(node, "autorepeat", NULL);
 473
 474         /* First count the subnodes */
 475         pdata->nbuttons = 0;
 476         pp = NULL;
 477         while ((pp = of_get_next_child(node, pp)))
 478                 pdata->nbuttons++;
 479
 480         if (pdata->nbuttons == 0)
 481                 return -ENODEV;
 482
 483         buttons = kzalloc(pdata->nbuttons * (sizeof *buttons), GFP_KERNEL);
 484         if (!buttons)
 485                 return -ENOMEM;
 486
 487         pp = NULL;
 488         i = 0;
 489         while ((pp = of_get_next_child(node, pp))) {
 490                 enum of_gpio_flags flags;
 491
 492                 if (!of_find_property(pp, "gpios", NULL)) {
 493                         pdata->nbuttons--;
 494                         dev_warn(dev, "Found button without gpios\n");
 495                         continue;
 496                 }
 497                 buttons[i].gpio = of_get_gpio_flags(pp, 0, &flags);
 498                 buttons[i].active_low = flags & OF_GPIO_ACTIVE_LOW;
 499
 500                 if (of_property_read_u32(pp, "linux,code", &reg)) {
 501                         dev_err(dev, "Button without keycode: 0x%x\n", buttons[i].gpio);
 502                         goto out_fail;
 503                 }
 504                 buttons[i].code = reg;
 505
 506                 buttons[i].desc = of_get_property(pp, "label", NULL);
 507
 508                 if (of_property_read_u32(pp, "linux,input-type", &reg) == 0)
 509                         buttons[i].type = reg;
 510                 else
 511                         buttons[i].type = EV_KEY;
 512
 513                 buttons[i].wakeup = !!of_get_property(pp, "gpio-key,wakeup", NULL);
 514
 515                 if (of_property_read_u32(pp, "debounce-interval", &reg) == 0)
 516                         buttons[i].debounce_interval = reg;
 517                 else
 518                         buttons[i].debounce_interval = 5;
 519
 520                 i++;
 521         }
 522
 523         pdata->buttons = buttons;
 524
 525         return 0;
 526
 527 out_fail:
 528         kfree(buttons);
 529         return -ENODEV;
 530 }
 531
 532 static struct of_device_id gpio_keys_of_match[] = {
 533         { .compatible = "gpio-keys", },
 534         { },
 535 };
 536 MODULE_DEVICE_TABLE(of, gpio_keys_of_match);
 537
 538 #else
 539
 540 static int gpio_keys_get_devtree_pdata(struct device *dev,
 541                             struct gpio_keys_platform_data *altp)
 542 {
 543         return -ENODEV;
 544 }
 545
 546 #define gpio_keys_of_match NULL
 547
 548 #endif
 549
 550 static int __devinit gpio_keys_probe(struct platform_device *pdev)
 551 {
 552         struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
 553         struct gpio_keys_drvdata *ddata;
 554         struct device *dev = &pdev->dev;
 555         struct gpio_keys_platform_data alt_pdata;
 556         struct input_dev *input;
 557         int i, error;
 558         int wakeup = 0;
 559
 560         if (!pdata) {
 561                 error = gpio_keys_get_devtree_pdata(dev, &alt_pdata);
 562                 if (error)
 563                         return error;
 564                 pdata = &alt_pdata;
 565         }
 566
 567         ddata = kzalloc(sizeof(struct gpio_keys_drvdata) +
 568                         pdata->nbuttons * sizeof(struct gpio_button_data),
 569                         GFP_KERNEL);
 570         input = input_allocate_device();
 571         if (!ddata || !input) {
 572                 dev_err(dev, "failed to allocate state\n");
 573                 error = -ENOMEM;
 574                 goto fail1;
 575         }
 576
 577         ddata->input = input;
 578         ddata->n_buttons = pdata->nbuttons;
 579         ddata->enable = pdata->enable;
 580         ddata->disable = pdata->disable;
 581         mutex_init(&ddata->disable_lock);
 582
 583         platform_set_drvdata(pdev, ddata);
 584         input_set_drvdata(input, ddata);
 585
 586         input->name = pdata->name ? : pdev->name;
 587         input->phys = "gpio-keys/input0";
 588         input->dev.parent = &pdev->dev;
 589         input->open = gpio_keys_open;
 590         input->close = gpio_keys_close;
 591
 592         input->id.bustype = BUS_HOST;
 593         input->id.vendor = 0x0001;
 594         input->id.product = 0x0001;
 595         input->id.version = 0x0100;
 596
 597         /* Enable auto repeat feature of Linux input subsystem */
 598         if (pdata->rep)
 599                 __set_bit(EV_REP, input->evbit);
 600
 601         for (i = 0; i < pdata->nbuttons; i++) {
 602                 struct gpio_keys_button *button = &pdata->buttons[i];
 603                 struct gpio_button_data *bdata = &ddata->data[i];
 604                 unsigned int type = button->type ?: EV_KEY;
 605
 606                 bdata->input = input;
 607                 bdata->button = button;
 608
 609                 error = gpio_keys_setup_key(pdev, bdata, button);
 610                 if (error)
 611                         goto fail2;
 612
 613                 if (button->wakeup)
 614                         wakeup = 1;
 615
 616                 input_set_capability(input, type, button->code);
 617         }
 618
 619         error = sysfs_create_group(&pdev->dev.kobj, &gpio_keys_attr_group);
 620         if (error) {
 621                 dev_err(dev, "Unable to export keys/switches, error: %d\n",
 622                         error);
 623                 goto fail2;
 624         }
 625
 626         error = input_register_device(input);
 627         if (error) {
 628                 dev_err(dev, "Unable to register input device, error: %d\n",
 629                         error);
 630                 goto fail3;
 631         }
 632
 633         /* get current state of buttons */
 634         for (i = 0; i < pdata->nbuttons; i++)
 635                 gpio_keys_report_event(&ddata->data[i]);
 636         input_sync(input);
 637
 638         device_init_wakeup(&pdev->dev, wakeup);
 639
 640         return 0;
 641
 642  fail3:
 643         sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group);
 644  fail2:
 645         while (--i >= 0) {
 646                 free_irq(gpio_to_irq(pdata->buttons[i].gpio), &ddata->data[i]);
 647                 if (ddata->data[i].timer_debounce)
 648                         del_timer_sync(&ddata->data[i].timer);
 649                 cancel_work_sync(&ddata->data[i].work);
 650                 gpio_free(pdata->buttons[i].gpio);
 651         }
 652
 653         platform_set_drvdata(pdev, NULL);
 654  fail1:
 655         input_free_device(input);
 656         kfree(ddata);
 657         /* If we have no platform_data, we allocated buttons dynamically. */
 658         if (!pdev->dev.platform_data)
 659                 kfree(pdata->buttons);
 660
 661         return error;
 662 }
 663
 664 static int __devexit gpio_keys_remove(struct platform_device *pdev)
 665 {
 666         struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);
 667         struct input_dev *input = ddata->input;
 668         int i;
 669
 670         sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group);
 671
 672         device_init_wakeup(&pdev->dev, 0);
 673
 674         for (i = 0; i < ddata->n_buttons; i++) {
 675                 int irq = gpio_to_irq(ddata->data[i].button->gpio);
 676                 free_irq(irq, &ddata->data[i]);
 677                 if (ddata->data[i].timer_debounce)
 678                         del_timer_sync(&ddata->data[i].timer);
 679                 cancel_work_sync(&ddata->data[i].work);
 680                 gpio_free(ddata->data[i].button->gpio);
 681         }
 682
 683         input_unregister_device(input);
 684
 685         /*
 686          * If we had no platform_data, we allocated buttons dynamically, and
 687          * must free them here. ddata->data[0].button is the pointer to the
 688          * beginning of the allocated array.
 689          */
 690         if (!pdev->dev.platform_data)
 691                 kfree(ddata->data[0].button);
 692
 693         kfree(ddata);
 694
 695         return 0;
 696 }
 697
 698 #ifdef CONFIG_PM_SLEEP
 699 static int gpio_keys_suspend(struct device *dev)
 700 {
 701         struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev);
 702         int i;
 703
 704         if (device_may_wakeup(dev)) {
 705                 for (i = 0; i < ddata->n_buttons; i++) {
 706                         struct gpio_keys_button *button = ddata->data[i].button;
 707                         if (button->wakeup) {
 708                                 int irq = gpio_to_irq(button->gpio);
 709                                 enable_irq_wake(irq);
 710                         }
 711                 }
 712         }
 713
 714         return 0;
 715 }
 716
 717 static int gpio_keys_resume(struct device *dev)
 718 {
 719         struct gpio_keys_drvdata *ddata = dev_get_drvdata(dev);
 720         int i;
 721
 722         for (i = 0; i < ddata->n_buttons; i++) {
 723
 724                 struct gpio_keys_button *button = ddata->data[i].button;
 725                 if (button->wakeup && device_may_wakeup(dev)) {
 726                         int irq = gpio_to_irq(button->gpio);
 727                         disable_irq_wake(irq);
 728                 }
 729
 730                 gpio_keys_report_event(&ddata->data[i]);
 731         }
 732         input_sync(ddata->input);
 733
 734         return 0;
 735 }
 736 #endif
 737
 738 static SIMPLE_DEV_PM_OPS(gpio_keys_pm_ops, gpio_keys_suspend, gpio_keys_resume);
 739
 740 static struct platform_driver gpio_keys_device_driver = {
 741         .probe          = gpio_keys_probe,
 742         .remove         = __devexit_p(gpio_keys_remove),
 743         .driver         = {
 744                 .name   = "gpio-keys",
 745                 .owner  = THIS_MODULE,
 746                 .pm     = &gpio_keys_pm_ops,
 747                 .of_match_table = gpio_keys_of_match,
 748         }
 749 };
 750
 751 static int __init gpio_keys_init(void)
 752 {
 753         return platform_driver_register(&gpio_keys_device_driver);
 754 }
 755
 756 static void __exit gpio_keys_exit(void)
 757 {
 758         platform_driver_unregister(&gpio_keys_device_driver);
 759 }
 760
 761 late_initcall(gpio_keys_init);
 762 module_exit(gpio_keys_exit);
 763
 764 MODULE_LICENSE("GPL");
 765 MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>");
 766 MODULE_DESCRIPTION("Keyboard driver for GPIOs");
 767 MODULE_ALIAS("platform:gpio-keys");