err.no Git - linux-2.6/blob - drivers/input/input.c

   1 /*
   2  * The input core
   3  *
   4  * Copyright (c) 1999-2002 Vojtech Pavlik
   5  */
   6
   7 /*
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License version 2 as published by
  10  * the Free Software Foundation.
  11  */
  12
  13 #include <linux/init.h>
  14 #include <linux/sched.h>
  15 #include <linux/smp_lock.h>
  16 #include <linux/input.h>
  17 #include <linux/module.h>
  18 #include <linux/random.h>
  19 #include <linux/major.h>
  20 #include <linux/proc_fs.h>
  21 #include <linux/kobject_uevent.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/poll.h>
  24 #include <linux/device.h>
  25
  26 MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
  27 MODULE_DESCRIPTION("Input core");
  28 MODULE_LICENSE("GPL");
  29
  30 EXPORT_SYMBOL(input_register_device);
  31 EXPORT_SYMBOL(input_unregister_device);
  32 EXPORT_SYMBOL(input_register_handler);
  33 EXPORT_SYMBOL(input_unregister_handler);
  34 EXPORT_SYMBOL(input_grab_device);
  35 EXPORT_SYMBOL(input_release_device);
  36 EXPORT_SYMBOL(input_open_device);
  37 EXPORT_SYMBOL(input_close_device);
  38 EXPORT_SYMBOL(input_accept_process);
  39 EXPORT_SYMBOL(input_flush_device);
  40 EXPORT_SYMBOL(input_event);
  41 EXPORT_SYMBOL(input_class);
  42
  43 #define INPUT_DEVICES   256
  44
  45 static LIST_HEAD(input_dev_list);
  46 static LIST_HEAD(input_handler_list);
  47
  48 static struct input_handler *input_table[8];
  49
  50 void input_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
  51 {
  52         struct input_handle *handle;
  53
  54         if (type > EV_MAX || !test_bit(type, dev->evbit))
  55                 return;
  56
  57         add_input_randomness(type, code, value);
  58
  59         switch (type) {
  60
  61                 case EV_SYN:
  62                         switch (code) {
  63                                 case SYN_CONFIG:
  64                                         if (dev->event) dev->event(dev, type, code, value);
  65                                         break;
  66
  67                                 case SYN_REPORT:
  68                                         if (dev->sync) return;
  69                                         dev->sync = 1;
  70                                         break;
  71                         }
  72                         break;
  73
  74                 case EV_KEY:
  75
  76                         if (code > KEY_MAX || !test_bit(code, dev->keybit) || !!test_bit(code, dev->key) == value)
  77                                 return;
  78
  79                         if (value == 2)
  80                                 break;
  81
  82                         change_bit(code, dev->key);
  83
  84                         if (test_bit(EV_REP, dev->evbit) && dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] && dev->timer.data && value) {
  85                                 dev->repeat_key = code;
  86                                 mod_timer(&dev->timer, jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
  87                         }
  88
  89                         break;
  90
  91                 case EV_SW:
  92
  93                         if (code > SW_MAX || !test_bit(code, dev->swbit) || !!test_bit(code, dev->sw) == value)
  94                                 return;
  95
  96                         change_bit(code, dev->sw);
  97
  98                         break;
  99
 100                 case EV_ABS:
 101
 102                         if (code > ABS_MAX || !test_bit(code, dev->absbit))
 103                                 return;
 104
 105                         if (dev->absfuzz[code]) {
 106                                 if ((value > dev->abs[code] - (dev->absfuzz[code] >> 1)) &&
 107                                     (value < dev->abs[code] + (dev->absfuzz[code] >> 1)))
 108                                         return;
 109
 110                                 if ((value > dev->abs[code] - dev->absfuzz[code]) &&
 111                                     (value < dev->abs[code] + dev->absfuzz[code]))
 112                                         value = (dev->abs[code] * 3 + value) >> 2;
 113
 114                                 if ((value > dev->abs[code] - (dev->absfuzz[code] << 1)) &&
 115                                     (value < dev->abs[code] + (dev->absfuzz[code] << 1)))
 116                                         value = (dev->abs[code] + value) >> 1;
 117                         }
 118
 119                         if (dev->abs[code] == value)
 120                                 return;
 121
 122                         dev->abs[code] = value;
 123                         break;
 124
 125                 case EV_REL:
 126
 127                         if (code > REL_MAX || !test_bit(code, dev->relbit) || (value == 0))
 128                                 return;
 129
 130                         break;
 131
 132                 case EV_MSC:
 133
 134                         if (code > MSC_MAX || !test_bit(code, dev->mscbit))
 135                                 return;
 136
 137                         if (dev->event) dev->event(dev, type, code, value);
 138
 139                         break;
 140
 141                 case EV_LED:
 142
 143                         if (code > LED_MAX || !test_bit(code, dev->ledbit) || !!test_bit(code, dev->led) == value)
 144                                 return;
 145
 146                         change_bit(code, dev->led);
 147                         if (dev->event) dev->event(dev, type, code, value);
 148
 149                         break;
 150
 151                 case EV_SND:
 152
 153                         if (code > SND_MAX || !test_bit(code, dev->sndbit))
 154                                 return;
 155
 156                         if (dev->event) dev->event(dev, type, code, value);
 157
 158                         break;
 159
 160                 case EV_REP:
 161
 162                         if (code > REP_MAX || value < 0 || dev->rep[code] == value) return;
 163
 164                         dev->rep[code] = value;
 165                         if (dev->event) dev->event(dev, type, code, value);
 166
 167                         break;
 168
 169                 case EV_FF:
 170                         if (dev->event) dev->event(dev, type, code, value);
 171                         break;
 172         }
 173
 174         if (type != EV_SYN)
 175                 dev->sync = 0;
 176
 177         if (dev->grab)
 178                 dev->grab->handler->event(dev->grab, type, code, value);
 179         else
 180                 list_for_each_entry(handle, &dev->h_list, d_node)
 181                         if (handle->open)
 182                                 handle->handler->event(handle, type, code, value);
 183 }
 184
 185 static void input_repeat_key(unsigned long data)
 186 {
 187         struct input_dev *dev = (void *) data;
 188
 189         if (!test_bit(dev->repeat_key, dev->key))
 190                 return;
 191
 192         input_event(dev, EV_KEY, dev->repeat_key, 2);
 193         input_sync(dev);
 194
 195         if (dev->rep[REP_PERIOD])
 196                 mod_timer(&dev->timer, jiffies + msecs_to_jiffies(dev->rep[REP_PERIOD]));
 197 }
 198
 199 int input_accept_process(struct input_handle *handle, struct file *file)
 200 {
 201         if (handle->dev->accept)
 202                 return handle->dev->accept(handle->dev, file);
 203
 204         return 0;
 205 }
 206
 207 int input_grab_device(struct input_handle *handle)
 208 {
 209         if (handle->dev->grab)
 210                 return -EBUSY;
 211
 212         handle->dev->grab = handle;
 213         return 0;
 214 }
 215
 216 void input_release_device(struct input_handle *handle)
 217 {
 218         if (handle->dev->grab == handle)
 219                 handle->dev->grab = NULL;
 220 }
 221
 222 int input_open_device(struct input_handle *handle)
 223 {
 224         struct input_dev *dev = handle->dev;
 225         int err;
 226
 227         err = down_interruptible(&dev->sem);
 228         if (err)
 229                 return err;
 230
 231         handle->open++;
 232
 233         if (!dev->users++ && dev->open)
 234                 err = dev->open(dev);
 235
 236         if (err)
 237                 handle->open--;
 238
 239         up(&dev->sem);
 240
 241         return err;
 242 }
 243
 244 int input_flush_device(struct input_handle* handle, struct file* file)
 245 {
 246         if (handle->dev->flush)
 247                 return handle->dev->flush(handle->dev, file);
 248
 249         return 0;
 250 }
 251
 252 void input_close_device(struct input_handle *handle)
 253 {
 254         struct input_dev *dev = handle->dev;
 255
 256         input_release_device(handle);
 257
 258         down(&dev->sem);
 259
 260         if (!--dev->users && dev->close)
 261                 dev->close(dev);
 262         handle->open--;
 263
 264         up(&dev->sem);
 265 }
 266
 267 static void input_link_handle(struct input_handle *handle)
 268 {
 269         list_add_tail(&handle->d_node, &handle->dev->h_list);
 270         list_add_tail(&handle->h_node, &handle->handler->h_list);
 271 }
 272
 273 #define MATCH_BIT(bit, max) \
 274                 for (i = 0; i < NBITS(max); i++) \
 275                         if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \
 276                                 break; \
 277                 if (i != NBITS(max)) \
 278                         continue;
 279
 280 static struct input_device_id *input_match_device(struct input_device_id *id, struct input_dev *dev)
 281 {
 282         int i;
 283
 284         for (; id->flags || id->driver_info; id++) {
 285
 286                 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
 287                         if (id->id.bustype != dev->id.bustype)
 288                                 continue;
 289
 290                 if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
 291                         if (id->id.vendor != dev->id.vendor)
 292                                 continue;
 293
 294                 if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
 295                         if (id->id.product != dev->id.product)
 296                                 continue;
 297
 298                 if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
 299                         if (id->id.version != dev->id.version)
 300                                 continue;
 301
 302                 MATCH_BIT(evbit,  EV_MAX);
 303                 MATCH_BIT(keybit, KEY_MAX);
 304                 MATCH_BIT(relbit, REL_MAX);
 305                 MATCH_BIT(absbit, ABS_MAX);
 306                 MATCH_BIT(mscbit, MSC_MAX);
 307                 MATCH_BIT(ledbit, LED_MAX);
 308                 MATCH_BIT(sndbit, SND_MAX);
 309                 MATCH_BIT(ffbit,  FF_MAX);
 310                 MATCH_BIT(swbit,  SW_MAX);
 311
 312                 return id;
 313         }
 314
 315         return NULL;
 316 }
 317
 318
 319 /*
 320  * Input hotplugging interface - loading event handlers based on
 321  * device bitfields.
 322  */
 323
 324 #ifdef CONFIG_HOTPLUG
 325
 326 /*
 327  * Input hotplugging invokes what /proc/sys/kernel/hotplug says
 328  * (normally /sbin/hotplug) when input devices get added or removed.
 329  *
 330  * This invokes a user mode policy agent, typically helping to load driver
 331  * or other modules, configure the device, and more.  Drivers can provide
 332  * a MODULE_DEVICE_TABLE to help with module loading subtasks.
 333  *
 334  */
 335
 336 #define SPRINTF_BIT_A(bit, name, max) \
 337         do { \
 338                 envp[i++] = scratch; \
 339                 scratch += sprintf(scratch, name); \
 340                 for (j = NBITS(max) - 1; j >= 0; j--) \
 341                         if (dev->bit[j]) break; \
 342                 for (; j >= 0; j--) \
 343                         scratch += sprintf(scratch, "%lx ", dev->bit[j]); \
 344                 scratch++; \
 345         } while (0)
 346
 347 #define SPRINTF_BIT_A2(bit, name, max, ev) \
 348         do { \
 349                 if (test_bit(ev, dev->evbit)) \
 350                         SPRINTF_BIT_A(bit, name, max); \
 351         } while (0)
 352
 353 static void input_call_hotplug(char *verb, struct input_dev *dev)
 354 {
 355         char *argv[3], **envp, *buf, *scratch;
 356         int i = 0, j, value;
 357
 358         if (!hotplug_path[0]) {
 359                 printk(KERN_ERR "input.c: calling hotplug without a hotplug agent defined\n");
 360                 return;
 361         }
 362         if (in_interrupt()) {
 363                 printk(KERN_ERR "input.c: calling hotplug from interrupt\n");
 364                 return;
 365         }
 366         if (!current->fs->root) {
 367                 printk(KERN_WARNING "input.c: calling hotplug without valid filesystem\n");
 368                 return;
 369         }
 370         if (!(envp = (char **) kmalloc(20 * sizeof(char *), GFP_KERNEL))) {
 371                 printk(KERN_ERR "input.c: not enough memory allocating hotplug environment\n");
 372                 return;
 373         }
 374         if (!(buf = kmalloc(1024, GFP_KERNEL))) {
 375                 kfree (envp);
 376                 printk(KERN_ERR "input.c: not enough memory allocating hotplug environment\n");
 377                 return;
 378         }
 379
 380         argv[0] = hotplug_path;
 381         argv[1] = "input";
 382         argv[2] = NULL;
 383
 384         envp[i++] = "HOME=/";
 385         envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
 386
 387         scratch = buf;
 388
 389         envp[i++] = scratch;
 390         scratch += sprintf(scratch, "ACTION=%s", verb) + 1;
 391
 392         envp[i++] = scratch;
 393         scratch += sprintf(scratch, "PRODUCT=%x/%x/%x/%x",
 394                 dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version) + 1;
 395
 396         if (dev->name) {
 397                 envp[i++] = scratch;
 398                 scratch += sprintf(scratch, "NAME=%s", dev->name) + 1;
 399         }
 400
 401         if (dev->phys) {
 402                 envp[i++] = scratch;
 403                 scratch += sprintf(scratch, "PHYS=%s", dev->phys) + 1;
 404         }
 405
 406         SPRINTF_BIT_A(evbit, "EV=", EV_MAX);
 407         SPRINTF_BIT_A2(keybit, "KEY=", KEY_MAX, EV_KEY);
 408         SPRINTF_BIT_A2(relbit, "REL=", REL_MAX, EV_REL);
 409         SPRINTF_BIT_A2(absbit, "ABS=", ABS_MAX, EV_ABS);
 410         SPRINTF_BIT_A2(mscbit, "MSC=", MSC_MAX, EV_MSC);
 411         SPRINTF_BIT_A2(ledbit, "LED=", LED_MAX, EV_LED);
 412         SPRINTF_BIT_A2(sndbit, "SND=", SND_MAX, EV_SND);
 413         SPRINTF_BIT_A2(ffbit,  "FF=",  FF_MAX, EV_FF);
 414         SPRINTF_BIT_A2(swbit,  "SW=",  SW_MAX, EV_SW);
 415
 416         envp[i++] = NULL;
 417
 418 #ifdef INPUT_DEBUG
 419         printk(KERN_DEBUG "input.c: calling %s %s [%s %s %s %s %s]\n",
 420                 argv[0], argv[1], envp[0], envp[1], envp[2], envp[3], envp[4]);
 421 #endif
 422
 423         value = call_usermodehelper(argv [0], argv, envp, 0);
 424
 425         kfree(buf);
 426         kfree(envp);
 427
 428 #ifdef INPUT_DEBUG
 429         if (value != 0)
 430                 printk(KERN_DEBUG "input.c: hotplug returned %d\n", value);
 431 #endif
 432 }
 433
 434 #endif
 435
 436 #ifdef CONFIG_PROC_FS
 437
 438 static struct proc_dir_entry *proc_bus_input_dir;
 439 static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
 440 static int input_devices_state;
 441
 442 static inline void input_wakeup_procfs_readers(void)
 443 {
 444         input_devices_state++;
 445         wake_up(&input_devices_poll_wait);
 446 }
 447
 448 static unsigned int input_devices_poll(struct file *file, poll_table *wait)
 449 {
 450         int state = input_devices_state;
 451         poll_wait(file, &input_devices_poll_wait, wait);
 452         if (state != input_devices_state)
 453                 return POLLIN | POLLRDNORM;
 454         return 0;
 455 }
 456
 457 #define SPRINTF_BIT_B(bit, name, max) \
 458         do { \
 459                 len += sprintf(buf + len, "B: %s", name); \
 460                 for (i = NBITS(max) - 1; i >= 0; i--) \
 461                         if (dev->bit[i]) break; \
 462                 for (; i >= 0; i--) \
 463                         len += sprintf(buf + len, "%lx ", dev->bit[i]); \
 464                 len += sprintf(buf + len, "\n"); \
 465         } while (0)
 466
 467 #define SPRINTF_BIT_B2(bit, name, max, ev) \
 468         do { \
 469                 if (test_bit(ev, dev->evbit)) \
 470                         SPRINTF_BIT_B(bit, name, max); \
 471         } while (0)
 472
 473 static int input_devices_read(char *buf, char **start, off_t pos, int count, int *eof, void *data)
 474 {
 475         struct input_dev *dev;
 476         struct input_handle *handle;
 477
 478         off_t at = 0;
 479         int i, len, cnt = 0;
 480
 481         list_for_each_entry(dev, &input_dev_list, node) {
 482
 483                 len = sprintf(buf, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
 484                         dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
 485
 486                 len += sprintf(buf + len, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
 487                 len += sprintf(buf + len, "P: Phys=%s\n", dev->phys ? dev->phys : "");
 488                 len += sprintf(buf + len, "H: Handlers=");
 489
 490                 list_for_each_entry(handle, &dev->h_list, d_node)
 491                         len += sprintf(buf + len, "%s ", handle->name);
 492
 493                 len += sprintf(buf + len, "\n");
 494
 495                 SPRINTF_BIT_B(evbit, "EV=", EV_MAX);
 496                 SPRINTF_BIT_B2(keybit, "KEY=", KEY_MAX, EV_KEY);
 497                 SPRINTF_BIT_B2(relbit, "REL=", REL_MAX, EV_REL);
 498                 SPRINTF_BIT_B2(absbit, "ABS=", ABS_MAX, EV_ABS);
 499                 SPRINTF_BIT_B2(mscbit, "MSC=", MSC_MAX, EV_MSC);
 500                 SPRINTF_BIT_B2(ledbit, "LED=", LED_MAX, EV_LED);
 501                 SPRINTF_BIT_B2(sndbit, "SND=", SND_MAX, EV_SND);
 502                 SPRINTF_BIT_B2(ffbit,  "FF=",  FF_MAX, EV_FF);
 503                 SPRINTF_BIT_B2(swbit,  "SW=",  SW_MAX, EV_SW);
 504
 505                 len += sprintf(buf + len, "\n");
 506
 507                 at += len;
 508
 509                 if (at >= pos) {
 510                         if (!*start) {
 511                                 *start = buf + (pos - (at - len));
 512                                 cnt = at - pos;
 513                         } else  cnt += len;
 514                         buf += len;
 515                         if (cnt >= count)
 516                                 break;
 517                 }
 518         }
 519
 520         if (&dev->node == &input_dev_list)
 521                 *eof = 1;
 522
 523         return (count > cnt) ? cnt : count;
 524 }
 525
 526 static int input_handlers_read(char *buf, char **start, off_t pos, int count, int *eof, void *data)
 527 {
 528         struct input_handler *handler;
 529
 530         off_t at = 0;
 531         int len = 0, cnt = 0;
 532         int i = 0;
 533
 534         list_for_each_entry(handler, &input_handler_list, node) {
 535
 536                 if (handler->fops)
 537                         len = sprintf(buf, "N: Number=%d Name=%s Minor=%d\n",
 538                                 i++, handler->name, handler->minor);
 539                 else
 540                         len = sprintf(buf, "N: Number=%d Name=%s\n",
 541                                 i++, handler->name);
 542
 543                 at += len;
 544
 545                 if (at >= pos) {
 546                         if (!*start) {
 547                                 *start = buf + (pos - (at - len));
 548                                 cnt = at - pos;
 549                         } else  cnt += len;
 550                         buf += len;
 551                         if (cnt >= count)
 552                                 break;
 553                 }
 554         }
 555         if (&handler->node == &input_handler_list)
 556                 *eof = 1;
 557
 558         return (count > cnt) ? cnt : count;
 559 }
 560
 561 static struct file_operations input_fileops;
 562
 563 static int __init input_proc_init(void)
 564 {
 565         struct proc_dir_entry *entry;
 566
 567         proc_bus_input_dir = proc_mkdir("input", proc_bus);
 568         if (!proc_bus_input_dir)
 569                 return -ENOMEM;
 570
 571         proc_bus_input_dir->owner = THIS_MODULE;
 572
 573         entry = create_proc_read_entry("devices", 0, proc_bus_input_dir, input_devices_read, NULL);
 574         if (!entry)
 575                 goto fail1;
 576
 577         entry->owner = THIS_MODULE;
 578         input_fileops = *entry->proc_fops;
 579         entry->proc_fops = &input_fileops;
 580         entry->proc_fops->poll = input_devices_poll;
 581
 582         entry = create_proc_read_entry("handlers", 0, proc_bus_input_dir, input_handlers_read, NULL);
 583         if (!entry)
 584                 goto fail2;
 585
 586         entry->owner = THIS_MODULE;
 587
 588         return 0;
 589
 590  fail2: remove_proc_entry("devices", proc_bus_input_dir);
 591  fail1: remove_proc_entry("input", proc_bus);
 592         return -ENOMEM;
 593 }
 594
 595 static void input_proc_exit(void)
 596 {
 597         remove_proc_entry("devices", proc_bus_input_dir);
 598         remove_proc_entry("handlers", proc_bus_input_dir);
 599         remove_proc_entry("input", proc_bus);
 600 }
 601
 602 #else /* !CONFIG_PROC_FS */
 603 static inline void input_wakeup_procfs_readers(void) { }
 604 static inline int input_proc_init(void) { return 0; }
 605 static inline void input_proc_exit(void) { }
 606 #endif
 607
 608 void input_register_device(struct input_dev *dev)
 609 {
 610         struct input_handle *handle;
 611         struct input_handler *handler;
 612         struct input_device_id *id;
 613
 614         set_bit(EV_SYN, dev->evbit);
 615
 616         init_MUTEX(&dev->sem);
 617
 618         /*
 619          * If delay and period are pre-set by the driver, then autorepeating
 620          * is handled by the driver itself and we don't do it in input.c.
 621          */
 622
 623         init_timer(&dev->timer);
 624         if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
 625                 dev->timer.data = (long) dev;
 626                 dev->timer.function = input_repeat_key;
 627                 dev->rep[REP_DELAY] = 250;
 628                 dev->rep[REP_PERIOD] = 33;
 629         }
 630
 631         INIT_LIST_HEAD(&dev->h_list);
 632         list_add_tail(&dev->node, &input_dev_list);
 633
 634         list_for_each_entry(handler, &input_handler_list, node)
 635                 if (!handler->blacklist || !input_match_device(handler->blacklist, dev))
 636                         if ((id = input_match_device(handler->id_table, dev)))
 637                                 if ((handle = handler->connect(handler, dev, id)))
 638                                         input_link_handle(handle);
 639
 640 #ifdef CONFIG_HOTPLUG
 641         input_call_hotplug("add", dev);
 642 #endif
 643
 644         input_wakeup_procfs_readers();
 645 }
 646
 647 void input_unregister_device(struct input_dev *dev)
 648 {
 649         struct list_head * node, * next;
 650
 651         if (!dev) return;
 652
 653         del_timer_sync(&dev->timer);
 654
 655         list_for_each_safe(node, next, &dev->h_list) {
 656                 struct input_handle * handle = to_handle(node);
 657                 list_del_init(&handle->d_node);
 658                 list_del_init(&handle->h_node);
 659                 handle->handler->disconnect(handle);
 660         }
 661
 662 #ifdef CONFIG_HOTPLUG
 663         input_call_hotplug("remove", dev);
 664 #endif
 665
 666         list_del_init(&dev->node);
 667
 668         input_wakeup_procfs_readers();
 669 }
 670
 671 void input_register_handler(struct input_handler *handler)
 672 {
 673         struct input_dev *dev;
 674         struct input_handle *handle;
 675         struct input_device_id *id;
 676
 677         if (!handler) return;
 678
 679         INIT_LIST_HEAD(&handler->h_list);
 680
 681         if (handler->fops != NULL)
 682                 input_table[handler->minor >> 5] = handler;
 683
 684         list_add_tail(&handler->node, &input_handler_list);
 685
 686         list_for_each_entry(dev, &input_dev_list, node)
 687                 if (!handler->blacklist || !input_match_device(handler->blacklist, dev))
 688                         if ((id = input_match_device(handler->id_table, dev)))
 689                                 if ((handle = handler->connect(handler, dev, id)))
 690                                         input_link_handle(handle);
 691
 692         input_wakeup_procfs_readers();
 693 }
 694
 695 void input_unregister_handler(struct input_handler *handler)
 696 {
 697         struct list_head * node, * next;
 698
 699         list_for_each_safe(node, next, &handler->h_list) {
 700                 struct input_handle * handle = to_handle_h(node);
 701                 list_del_init(&handle->h_node);
 702                 list_del_init(&handle->d_node);
 703                 handler->disconnect(handle);
 704         }
 705
 706         list_del_init(&handler->node);
 707
 708         if (handler->fops != NULL)
 709                 input_table[handler->minor >> 5] = NULL;
 710
 711         input_wakeup_procfs_readers();
 712 }
 713
 714 static int input_open_file(struct inode *inode, struct file *file)
 715 {
 716         struct input_handler *handler = input_table[iminor(inode) >> 5];
 717         struct file_operations *old_fops, *new_fops = NULL;
 718         int err;
 719
 720         /* No load-on-demand here? */
 721         if (!handler || !(new_fops = fops_get(handler->fops)))
 722                 return -ENODEV;
 723
 724         /*
 725          * That's _really_ odd. Usually NULL ->open means "nothing special",
 726          * not "no device". Oh, well...
 727          */
 728         if (!new_fops->open) {
 729                 fops_put(new_fops);
 730                 return -ENODEV;
 731         }
 732         old_fops = file->f_op;
 733         file->f_op = new_fops;
 734
 735         err = new_fops->open(inode, file);
 736
 737         if (err) {
 738                 fops_put(file->f_op);
 739                 file->f_op = fops_get(old_fops);
 740         }
 741         fops_put(old_fops);
 742         return err;
 743 }
 744
 745 static struct file_operations input_fops = {
 746         .owner = THIS_MODULE,
 747         .open = input_open_file,
 748 };
 749
 750 struct class *input_class;
 751
 752 static int __init input_init(void)
 753 {
 754         int err;
 755
 756         input_class = class_create(THIS_MODULE, "input");
 757         if (IS_ERR(input_class)) {
 758                 printk(KERN_ERR "input: unable to register input class\n");
 759                 return PTR_ERR(input_class);
 760         }
 761
 762         err = input_proc_init();
 763         if (err)
 764                 goto fail1;
 765
 766         err = register_chrdev(INPUT_MAJOR, "input", &input_fops);
 767         if (err) {
 768                 printk(KERN_ERR "input: unable to register char major %d", INPUT_MAJOR);
 769                 goto fail2;
 770         }
 771
 772         return 0;
 773
 774  fail2: input_proc_exit();
 775  fail1: class_destroy(input_class);
 776         return err;
 777 }
 778
 779 static void __exit input_exit(void)
 780 {
 781         input_proc_exit();
 782         unregister_chrdev(INPUT_MAJOR, "input");
 783         class_destroy(input_class);
 784 }
 785
 786 subsys_initcall(input_init);
 787 module_exit(input_exit);