cvs.zerfleddert.de Git - ms2-fixes/blob - debounce.c

   1 #include <linux/module.h>
   2 #include <linux/device.h>
   3 #include <linux/platform_device.h>
   4 #include <linux/gpio_event.h>
   5 #include <linux/interrupt.h>
   6 #include <linux/irq.h>
   7 #include <mach/gpio.h>
   8
   9 #define PREFIX "debounce: "
  10
  11 static unsigned old_flags = 0;
  12 static ktime_t old_debounce_delay;
  13 static ktime_t old_settle_time;
  14 static ktime_t old_poll_time;
  15 static struct gpio_event_matrix_info *gpio_evmi = NULL;
  16 static int hw_debounce = 0;
  17 static int hw_debounce_time = 0;
  18
  19 static int find_ms2_dev(struct device *dev, void *data)
  20 {
  21         if (!strncmp((char*)data, dev_name(dev), strlen((char*)data))) {
  22                 printk(KERN_INFO PREFIX "Found it\n");
  23                 return 1;
  24         }
  25         return 0;
  26 }
  27
  28 /* hardware debounce: (time + 1) * 31us */
  29 static void hw_debounce_set(int enable, int time) {
  30         int i;
  31
  32         if (gpio_evmi == NULL)
  33                 return;
  34
  35         for (i = 0; i < gpio_evmi->ninputs; i++) {
  36                 int gpio = gpio_evmi->input_gpios[i];
  37
  38                 if ((time != -1) && (time != hw_debounce_time) && hw_debounce) {
  39                         printk(KERN_INFO PREFIX "Setting hardware debounce time for GPIO %d to %d (%dus)\n", gpio, time, (time+1)*31);
  40                         omap_set_gpio_debounce_time(gpio, time);
  41                 }
  42
  43                 if ((enable != -1) && (enable != hw_debounce)) {
  44                         printk(KERN_INFO PREFIX "%sabling hardware debounce for GPIO %d\n", (enable?"En":"Dis"), gpio);
  45                         omap_set_gpio_debounce(gpio, enable);
  46                 }
  47         }
  48 }
  49
  50 static void set_irq_types(void) {
  51         int err;
  52         unsigned int irq;
  53         unsigned long type;
  54         int i;
  55
  56         if (gpio_evmi == NULL)
  57                 return;
  58
  59         switch (gpio_evmi->flags & (GPIOKPF_ACTIVE_HIGH|GPIOKPF_LEVEL_TRIGGERED_IRQ)) {
  60         default:
  61                 type = IRQ_TYPE_EDGE_FALLING;
  62                 break;
  63         case GPIOKPF_ACTIVE_HIGH:
  64                 type = IRQ_TYPE_EDGE_RISING;
  65                 break;
  66         case GPIOKPF_LEVEL_TRIGGERED_IRQ:
  67                 type = IRQ_TYPE_LEVEL_LOW;
  68                 break;
  69         case GPIOKPF_LEVEL_TRIGGERED_IRQ | GPIOKPF_ACTIVE_HIGH:
  70                 type = IRQ_TYPE_LEVEL_HIGH;
  71                 break;
  72         }
  73
  74         printk(KERN_INFO PREFIX "Settinhg IRQ type to 0x%lx\n", type);
  75
  76         for (i = 0; i < gpio_evmi->ninputs; i++) {
  77
  78                 err = irq = gpio_to_irq(gpio_evmi->input_gpios[i]);
  79
  80                 if (err < 0)
  81                         return;
  82
  83                 err = set_irq_type(irq, type);
  84         }
  85 }
  86
  87 static ssize_t show_debounce_delay(struct device *dev, struct device_attribute *attr, char *buf)
  88 {
  89         if (!gpio_evmi)
  90                 return -ENODEV;
  91
  92         return snprintf(buf, PAGE_SIZE, "%ld\n", (gpio_evmi->debounce_delay.tv.nsec / NSEC_PER_MSEC));
  93 }
  94
  95 static void set_debounce_delay(long delay)
  96 {
  97         if (gpio_evmi->debounce_delay.tv.nsec != delay * NSEC_PER_MSEC) {
  98                 printk(KERN_INFO PREFIX "Changing debounce_delay\n");
  99                 gpio_evmi->debounce_delay.tv.nsec = delay * NSEC_PER_MSEC;
 100                 printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
 101         }
 102
 103 #if 0
 104         if (gpio_evmi->debounce_delay.tv.nsec != 0) {
 105                 if (!(gpio_evmi->flags & GPIOKPF_DEBOUNCE)) {
 106                         printk(KERN_INFO PREFIX "Activating debounce\n");
 107                         gpio_evmi->flags |= GPIOKPF_DEBOUNCE;
 108                 }
 109         } else {
 110                 if (gpio_evmi->flags & GPIOKPF_DEBOUNCE) {
 111                         printk(KERN_INFO PREFIX "Deactivating debounce\n");
 112                         gpio_evmi->flags &= ~GPIOKPF_DEBOUNCE;
 113                 }
 114         }
 115 #endif
 116 }
 117
 118 static ssize_t store_debounce_delay(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 119 {
 120         long int delay;
 121
 122         if (!gpio_evmi)
 123                 return -ENODEV;
 124
 125         sscanf(buf, "%ld", &delay);
 126         set_debounce_delay(delay);
 127
 128         return count;
 129 }
 130
 131 static ssize_t show_settle_time(struct device *dev, struct device_attribute *attr, char *buf)
 132 {
 133         if (!gpio_evmi)
 134                 return -ENODEV;
 135
 136         return snprintf(buf, PAGE_SIZE, "%ld\n", (gpio_evmi->settle_time.tv.nsec / NSEC_PER_USEC));
 137 }
 138
 139 static ssize_t store_settle_time(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 140 {
 141         long int delay;
 142
 143         if (!gpio_evmi)
 144                 return -ENODEV;
 145
 146         sscanf(buf, "%ld", &delay);
 147         gpio_evmi->settle_time.tv.nsec = delay * NSEC_PER_USEC;
 148
 149         return count;
 150 }
 151
 152 static ssize_t show_poll_time(struct device *dev, struct device_attribute *attr, char *buf)
 153 {
 154         if (!gpio_evmi)
 155                 return -ENODEV;
 156
 157         return snprintf(buf, PAGE_SIZE, "%ld\n", (gpio_evmi->poll_time.tv.nsec / NSEC_PER_MSEC));
 158 }
 159
 160 static ssize_t store_poll_time(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 161 {
 162         long int delay;
 163
 164         if (!gpio_evmi)
 165                 return -ENODEV;
 166
 167         sscanf(buf, "%ld", &delay);
 168         gpio_evmi->poll_time.tv.nsec = delay * NSEC_PER_MSEC;
 169
 170         return count;
 171 }
 172
 173 static ssize_t show_flags(struct device *dev, struct device_attribute *attr, char *buf)
 174 {
 175         if (!gpio_evmi)
 176                 return -ENODEV;
 177
 178         return snprintf(buf, PAGE_SIZE, "0x%x\n", gpio_evmi->flags);
 179 }
 180
 181 static ssize_t store_flags(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 182 {
 183         unsigned flags;
 184
 185         if (!gpio_evmi)
 186                 return -ENODEV;
 187
 188         sscanf(buf, "0x%x", &flags);
 189
 190         printk(KERN_INFO PREFIX "flags: 0x%x\n", flags);
 191
 192         gpio_evmi->flags = flags;
 193
 194         return count;
 195 }
 196
 197 static ssize_t show_debounce_flag(struct device *dev, struct device_attribute *attr, char *buf)
 198 {
 199         if (!gpio_evmi)
 200                 return -ENODEV;
 201
 202         return snprintf(buf, PAGE_SIZE, "%u\n", (gpio_evmi->flags & GPIOKPF_DEBOUNCE) ? 1 : 0);
 203 }
 204
 205 static ssize_t store_debounce_flag(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 206 {
 207         unsigned flag;
 208
 209         if (!gpio_evmi)
 210                 return -ENODEV;
 211
 212         sscanf(buf, "%u", &flag);
 213
 214         if (flag) {
 215                 gpio_evmi->flags |= GPIOKPF_DEBOUNCE;
 216         } else {
 217                 gpio_evmi->flags &= ~GPIOKPF_DEBOUNCE;
 218         }
 219
 220         return count;
 221 }
 222
 223 static ssize_t show_remove_some_phantom_keys_flag(struct device *dev, struct device_attribute *attr, char *buf)
 224 {
 225         if (!gpio_evmi)
 226                 return -ENODEV;
 227
 228         return snprintf(buf, PAGE_SIZE, "%u\n", (gpio_evmi->flags & GPIOKPF_REMOVE_SOME_PHANTOM_KEYS) ? 1 : 0);
 229 }
 230
 231 static ssize_t store_remove_some_phantom_keys_flag(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 232 {
 233         unsigned flag;
 234
 235         if (!gpio_evmi)
 236                 return -ENODEV;
 237
 238         sscanf(buf, "%u", &flag);
 239
 240         if (flag) {
 241                 gpio_evmi->flags |= GPIOKPF_REMOVE_SOME_PHANTOM_KEYS;
 242         } else {
 243                 gpio_evmi->flags &= ~GPIOKPF_REMOVE_SOME_PHANTOM_KEYS;
 244         }
 245
 246         return count;
 247 }
 248
 249 static ssize_t show_print_unmapped_keys_flag(struct device *dev, struct device_attribute *attr, char *buf)
 250 {
 251         if (!gpio_evmi)
 252                 return -ENODEV;
 253
 254         return snprintf(buf, PAGE_SIZE, "%u\n", (gpio_evmi->flags & GPIOKPF_PRINT_UNMAPPED_KEYS) ? 1 : 0);
 255 }
 256
 257 static ssize_t store_print_unmapped_keys_flag(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 258 {
 259         unsigned flag;
 260
 261         if (!gpio_evmi)
 262                 return -ENODEV;
 263
 264         sscanf(buf, "%u", &flag);
 265
 266         if (flag) {
 267                 gpio_evmi->flags |= GPIOKPF_PRINT_UNMAPPED_KEYS;
 268         } else {
 269                 gpio_evmi->flags &= ~GPIOKPF_PRINT_UNMAPPED_KEYS;
 270         }
 271
 272         return count;
 273 }
 274
 275 static ssize_t show_print_mapped_keys_flag(struct device *dev, struct device_attribute *attr, char *buf)
 276 {
 277         if (!gpio_evmi)
 278                 return -ENODEV;
 279
 280         return snprintf(buf, PAGE_SIZE, "%u\n", (gpio_evmi->flags & GPIOKPF_PRINT_MAPPED_KEYS) ? 1 : 0);
 281 }
 282
 283 static ssize_t store_print_mapped_keys_flag(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 284 {
 285         unsigned flag;
 286
 287         if (!gpio_evmi)
 288                 return -ENODEV;
 289
 290         sscanf(buf, "%u", &flag);
 291
 292         if (flag) {
 293                 gpio_evmi->flags |= GPIOKPF_PRINT_MAPPED_KEYS;
 294         } else {
 295                 gpio_evmi->flags &= ~GPIOKPF_PRINT_MAPPED_KEYS;
 296         }
 297
 298         return count;
 299 }
 300
 301 static ssize_t show_print_phantom_keys_flag(struct device *dev, struct device_attribute *attr, char *buf)
 302 {
 303         if (!gpio_evmi)
 304                 return -ENODEV;
 305
 306         return snprintf(buf, PAGE_SIZE, "%u\n", (gpio_evmi->flags & GPIOKPF_PRINT_PHANTOM_KEYS) ? 1 : 0);
 307 }
 308
 309 static ssize_t store_print_phantom_keys_flag(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 310 {
 311         unsigned flag;
 312
 313         if (!gpio_evmi)
 314                 return -ENODEV;
 315
 316         sscanf(buf, "%u", &flag);
 317
 318         if (flag) {
 319                 gpio_evmi->flags |= GPIOKPF_PRINT_PHANTOM_KEYS;
 320         } else {
 321                 gpio_evmi->flags &= ~GPIOKPF_PRINT_PHANTOM_KEYS;
 322         }
 323
 324         return count;
 325 }
 326
 327 static ssize_t show_active_high_flag(struct device *dev, struct device_attribute *attr, char *buf)
 328 {
 329         if (!gpio_evmi)
 330                 return -ENODEV;
 331
 332         return snprintf(buf, PAGE_SIZE, "%u\n", (gpio_evmi->flags & GPIOKPF_ACTIVE_HIGH) ? 1 : 0);
 333 }
 334
 335 static ssize_t store_active_high_flag(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 336 {
 337         unsigned flag;
 338
 339         if (!gpio_evmi)
 340                 return -ENODEV;
 341
 342         sscanf(buf, "%u", &flag);
 343
 344         if (flag) {
 345                 gpio_evmi->flags |= GPIOKPF_ACTIVE_HIGH;
 346         } else {
 347                 gpio_evmi->flags &= ~GPIOKPF_ACTIVE_HIGH;
 348         }
 349
 350         set_irq_types();
 351
 352         return count;
 353 }
 354
 355 static ssize_t show_level_triggered_irq_flag(struct device *dev, struct device_attribute *attr, char *buf)
 356 {
 357         if (!gpio_evmi)
 358                 return -ENODEV;
 359
 360         return snprintf(buf, PAGE_SIZE, "%u\n", (gpio_evmi->flags & GPIOKPF_LEVEL_TRIGGERED_IRQ) ? 1 : 0);
 361 }
 362
 363 static ssize_t store_level_triggered_irq_flag(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 364 {
 365         unsigned flag;
 366
 367         if (!gpio_evmi)
 368                 return -ENODEV;
 369
 370         sscanf(buf, "%u", &flag);
 371
 372         if (flag) {
 373                 gpio_evmi->flags |= GPIOKPF_LEVEL_TRIGGERED_IRQ;
 374         } else {
 375                 gpio_evmi->flags &= ~GPIOKPF_LEVEL_TRIGGERED_IRQ;
 376         }
 377
 378         set_irq_types();
 379
 380         return count;
 381 }
 382
 383 static ssize_t show_drive_inactive_flag(struct device *dev, struct device_attribute *attr, char *buf)
 384 {
 385         if (!gpio_evmi)
 386                 return -ENODEV;
 387
 388         return snprintf(buf, PAGE_SIZE, "%u\n", (gpio_evmi->flags & GPIOKPF_DRIVE_INACTIVE) ? 1 : 0);
 389 }
 390
 391 static ssize_t store_drive_inactive_flag(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 392 {
 393         unsigned flag;
 394
 395         if (!gpio_evmi)
 396                 return -ENODEV;
 397
 398         sscanf(buf, "%u", &flag);
 399
 400         if (flag) {
 401                 gpio_evmi->flags |= GPIOKPF_DRIVE_INACTIVE;
 402         } else {
 403                 gpio_evmi->flags &= ~GPIOKPF_DRIVE_INACTIVE;
 404         }
 405
 406         return count;
 407 }
 408
 409 static ssize_t show_hw_debounce(struct device *dev, struct device_attribute *attr, char *buf)
 410 {
 411         return snprintf(buf, PAGE_SIZE, "%d\n", hw_debounce);
 412 }
 413
 414 static ssize_t store_hw_debounce(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 415 {
 416         int enable;
 417
 418         sscanf(buf, "%d", &enable);
 419
 420         if (enable) {
 421                 hw_debounce_set(1, -1);
 422                 hw_debounce = 1;
 423         }
 424         else {
 425                 hw_debounce_set(-1, 0);
 426                 hw_debounce_set(0, -1);
 427                 hw_debounce = 0;
 428                 hw_debounce_time = 0;
 429         }
 430
 431         return count;
 432 }
 433
 434 static ssize_t show_hw_debounce_time(struct device *dev, struct device_attribute *attr, char *buf)
 435 {
 436         return snprintf(buf, PAGE_SIZE, "%d\n", hw_debounce_time);
 437 }
 438
 439 static ssize_t store_hw_debounce_time(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 440 {
 441         int time;
 442
 443         sscanf(buf, "%d", &time);
 444
 445         if ((time < 0) || (time > 0xff))
 446                 return count;
 447
 448         if (!hw_debounce)
 449                 return count;
 450
 451         hw_debounce_set(-1, time);
 452         hw_debounce_time = time;
 453
 454         return count;
 455 }
 456
 457 static DEVICE_ATTR(debounce_delay, (S_IRUGO | S_IWUGO), show_debounce_delay, store_debounce_delay);
 458 static DEVICE_ATTR(settle_time, (S_IRUGO | S_IWUGO), show_settle_time, store_settle_time);
 459 static DEVICE_ATTR(poll_time, (S_IRUGO | S_IWUGO), show_poll_time, store_poll_time);
 460 static DEVICE_ATTR(flags, (S_IRUGO), show_flags, store_flags);
 461 static DEVICE_ATTR(debounce_flag, (S_IRUGO | S_IWUGO), show_debounce_flag, store_debounce_flag);
 462 static DEVICE_ATTR(remove_some_phantom_keys_flag, (S_IRUGO | S_IWUGO), show_remove_some_phantom_keys_flag, store_remove_some_phantom_keys_flag);
 463 static DEVICE_ATTR(print_unmapped_keys_flag, (S_IRUGO | S_IWUGO), show_print_unmapped_keys_flag, store_print_unmapped_keys_flag);
 464 static DEVICE_ATTR(print_mapped_keys_flag, (S_IRUGO | S_IWUGO), show_print_mapped_keys_flag, store_print_mapped_keys_flag);
 465 static DEVICE_ATTR(print_phantom_keys_flag, (S_IRUGO | S_IWUGO), show_print_phantom_keys_flag, store_print_phantom_keys_flag);
 466 static DEVICE_ATTR(active_high_flag, (S_IRUGO), show_active_high_flag, store_active_high_flag);
 467 static DEVICE_ATTR(level_triggered_irq_flag, (S_IRUGO | S_IWUGO), show_level_triggered_irq_flag, store_level_triggered_irq_flag);
 468 static DEVICE_ATTR(drive_inactive_flag, (S_IRUGO | S_IWUGO), show_drive_inactive_flag, store_drive_inactive_flag);
 469 static DEVICE_ATTR(hw_debounce, (S_IRUGO | S_IWUGO), show_hw_debounce, store_hw_debounce);
 470 static DEVICE_ATTR(hw_debounce_time, (S_IRUGO | S_IWUGO), show_hw_debounce_time, store_hw_debounce_time);
 471
 472 static void debounce_release(struct device *dev)
 473 {
 474 }
 475
 476 static struct device debounce_device = {
 477         .init_name = "debounce",
 478         .release = debounce_release,
 479 };
 480
 481 static int __init debounce_init(void)
 482 {
 483         struct device *event_dev = NULL;
 484         struct gpio_event_platform_data *gpio_epd;
 485         struct gpio_event_info *gpio_ei;
 486         int err = 0;
 487
 488         printk(KERN_INFO PREFIX "Searching for " GPIO_EVENT_DEV_NAME "...\n");
 489
 490         event_dev = device_find_child(&platform_bus, GPIO_EVENT_DEV_NAME, find_ms2_dev);
 491         if (event_dev == NULL)
 492                 return -ENODEV;
 493
 494         gpio_epd = (struct gpio_event_platform_data*)event_dev->platform_data;
 495         printk(KERN_INFO PREFIX "And there is a %s connected...\n", gpio_epd->name);
 496         if (strcmp(gpio_epd->name, "sholes-keypad"))
 497                 return -ENODEV;
 498
 499         gpio_ei = (struct gpio_event_info*)gpio_epd->info[0];
 500         gpio_evmi = container_of(gpio_ei, struct gpio_event_matrix_info, info);
 501
 502         err = device_register(&debounce_device);
 503         if (err) {
 504                 return err;
 505         }
 506
 507         err = device_create_file(&debounce_device, &dev_attr_debounce_delay);
 508         err = device_create_file(&debounce_device, &dev_attr_settle_time);
 509         err = device_create_file(&debounce_device, &dev_attr_poll_time);
 510         err = device_create_file(&debounce_device, &dev_attr_flags);
 511         err = device_create_file(&debounce_device, &dev_attr_debounce_flag);
 512         err = device_create_file(&debounce_device, &dev_attr_remove_some_phantom_keys_flag);
 513         err = device_create_file(&debounce_device, &dev_attr_print_unmapped_keys_flag);
 514         err = device_create_file(&debounce_device, &dev_attr_print_mapped_keys_flag);
 515         err = device_create_file(&debounce_device, &dev_attr_print_phantom_keys_flag);
 516         err = device_create_file(&debounce_device, &dev_attr_active_high_flag);
 517         err = device_create_file(&debounce_device, &dev_attr_level_triggered_irq_flag);
 518         err = device_create_file(&debounce_device, &dev_attr_drive_inactive_flag);
 519         err = device_create_file(&debounce_device, &dev_attr_hw_debounce);
 520         err = device_create_file(&debounce_device, &dev_attr_hw_debounce_time);
 521
 522         printk(KERN_INFO PREFIX "settle_time: %u\n", gpio_evmi->settle_time.tv.nsec);
 523         printk(KERN_INFO PREFIX "poll_time: %u\n", gpio_evmi->poll_time.tv.nsec);
 524         printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
 525         printk(KERN_INFO PREFIX "flags: 0x%x\n", gpio_evmi->flags);
 526
 527         old_debounce_delay = gpio_evmi->debounce_delay;
 528         old_settle_time = gpio_evmi->settle_time;
 529         old_poll_time = gpio_evmi->poll_time;
 530         old_flags = gpio_evmi->flags;
 531
 532         printk(KERN_INFO PREFIX "flags: 0x%x\n", gpio_evmi->flags);
 533
 534         return 0;
 535 }
 536
 537 static void __exit debounce_exit(void)
 538 {
 539         if (gpio_evmi) {
 540                 if (gpio_evmi->debounce_delay.tv.nsec != old_debounce_delay.tv.nsec) {
 541                         printk(KERN_INFO PREFIX "Restoring debounce_delay\n");
 542                         gpio_evmi->debounce_delay = old_debounce_delay;
 543                         printk(KERN_INFO PREFIX "debounce_delay: %u\n", gpio_evmi->debounce_delay.tv.nsec);
 544                 }
 545                 if (gpio_evmi->flags != old_flags) {
 546                         printk(KERN_INFO PREFIX "Restoring flags\n");
 547                         gpio_evmi->flags = old_flags;
 548                         printk(KERN_INFO PREFIX "flags: 0x%x\n", gpio_evmi->flags);
 549                         set_irq_types();
 550                 }
 551                 gpio_evmi->settle_time = old_settle_time;
 552                 gpio_evmi->poll_time = old_poll_time;
 553         }
 554         hw_debounce_set(0, 0);
 555         device_remove_file(&debounce_device, &dev_attr_debounce_delay);
 556         device_remove_file(&debounce_device, &dev_attr_settle_time);
 557         device_remove_file(&debounce_device, &dev_attr_poll_time);
 558         device_remove_file(&debounce_device, &dev_attr_flags);
 559         device_remove_file(&debounce_device, &dev_attr_debounce_flag);
 560         device_remove_file(&debounce_device, &dev_attr_remove_some_phantom_keys_flag);
 561         device_remove_file(&debounce_device, &dev_attr_print_unmapped_keys_flag);
 562         device_remove_file(&debounce_device, &dev_attr_print_mapped_keys_flag);
 563         device_remove_file(&debounce_device, &dev_attr_print_phantom_keys_flag);
 564         device_remove_file(&debounce_device, &dev_attr_active_high_flag);
 565         device_remove_file(&debounce_device, &dev_attr_level_triggered_irq_flag);
 566         device_remove_file(&debounce_device, &dev_attr_drive_inactive_flag);
 567         device_remove_file(&debounce_device, &dev_attr_hw_debounce);
 568         device_remove_file(&debounce_device, &dev_attr_hw_debounce_time);
 569         device_unregister(&debounce_device);
 570 }
 571
 572 module_init(debounce_init);
 573 module_exit(debounce_exit);
 574
 575 MODULE_LICENSE("GPL");
 576 MODULE_AUTHOR("Michael Gernoth <michael@gernoth.net>");