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 #include <linux/devfs_fs_kernel.h>
  26
  27 MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
  28 MODULE_DESCRIPTION("Input core");
  29 MODULE_LICENSE("GPL");
  30
  31 EXPORT_SYMBOL(input_register_device);
  32 EXPORT_SYMBOL(input_unregister_device);
  33 EXPORT_SYMBOL(input_register_handler);
  34 EXPORT_SYMBOL(input_unregister_handler);
  35 EXPORT_SYMBOL(input_grab_device);
  36 EXPORT_SYMBOL(input_release_device);
  37 EXPORT_SYMBOL(input_open_device);
  38 EXPORT_SYMBOL(input_close_device);
  39 EXPORT_SYMBOL(input_accept_process);
  40 EXPORT_SYMBOL(input_flush_device);
  41 EXPORT_SYMBOL(input_event);
  42 EXPORT_SYMBOL(input_class);
  43
  44 #define INPUT_DEVICES   256
  45
  46 static LIST_HEAD(input_dev_list);
  47 static LIST_HEAD(input_handler_list);
  48
  49 static struct input_handler *input_table[8];
  50
  51 void input_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
  52 {
  53         struct input_handle *handle;
  54
  55         if (type > EV_MAX || !test_bit(type, dev->evbit))
  56                 return;
  57
  58         add_input_randomness(type, code, value);
  59
  60         switch (type) {
  61
  62                 case EV_SYN:
  63                         switch (code) {
  64                                 case SYN_CONFIG:
  65                                         if (dev->event) dev->event(dev, type, code, value);
  66                                         break;
  67
  68                                 case SYN_REPORT:
  69                                         if (dev->sync) return;
  70                                         dev->sync = 1;
  71                                         break;
  72                         }
  73                         break;
  74
  75                 case EV_KEY:
  76
  77                         if (code > KEY_MAX || !test_bit(code, dev->keybit) || !!test_bit(code, dev->key) == value)
  78                                 return;
  79
  80                         if (value == 2)
  81                                 break;
  82
  83                         change_bit(code, dev->key);
  84
  85                         if (test_bit(EV_REP, dev->evbit) && dev->rep[REP_PERIOD] && dev->rep[REP_DELAY] && dev->timer.data && value) {
  86                                 dev->repeat_key = code;
  87                                 mod_timer(&dev->timer, jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]));
  88                         }
  89
  90                         break;
  91
  92                 case EV_ABS:
  93
  94                         if (code > ABS_MAX || !test_bit(code, dev->absbit))
  95                                 return;
  96
  97                         if (dev->absfuzz[code]) {
  98                                 if ((value > dev->abs[code] - (dev->absfuzz[code] >> 1)) &&
  99                                     (value < dev->abs[code] + (dev->absfuzz[code] >> 1)))
 100                                         return;
 101
 102                                 if ((value > dev->abs[code] - dev->absfuzz[code]) &&
 103                                     (value < dev->abs[code] + dev->absfuzz[code]))
 104                                         value = (dev->abs[code] * 3 + value) >> 2;
 105
 106                                 if ((value > dev->abs[code] - (dev->absfuzz[code] << 1)) &&
 107                                     (value < dev->abs[code] + (dev->absfuzz[code] << 1)))
 108                                         value = (dev->abs[code] + value) >> 1;
 109                         }
 110
 111                         if (dev->abs[code] == value)
 112                                 return;
 113
 114                         dev->abs[code] = value;
 115                         break;
 116
 117                 case EV_REL:
 118
 119                         if (code > REL_MAX || !test_bit(code, dev->relbit) || (value == 0))
 120                                 return;
 121
 122                         break;
 123
 124                 case EV_MSC:
 125
 126                         if (code > MSC_MAX || !test_bit(code, dev->mscbit))
 127                                 return;
 128
 129                         if (dev->event) dev->event(dev, type, code, value);
 130
 131                         break;
 132
 133                 case EV_LED:
 134
 135                         if (code > LED_MAX || !test_bit(code, dev->ledbit) || !!test_bit(code, dev->led) == value)
 136                                 return;
 137
 138                         change_bit(code, dev->led);
 139                         if (dev->event) dev->event(dev, type, code, value);
 140
 141                         break;
 142
 143                 case EV_SND:
 144
 145                         if (code > SND_MAX || !test_bit(code, dev->sndbit))
 146                                 return;
 147
 148                         if (dev->event) dev->event(dev, type, code, value);
 149
 150                         break;
 151
 152                 case EV_REP:
 153
 154                         if (code > REP_MAX || value < 0 || dev->rep[code] == value) return;
 155
 156                         dev->rep[code] = value;
 157                         if (dev->event) dev->event(dev, type, code, value);
 158
 159                         break;
 160
 161                 case EV_FF:
 162                         if (dev->event) dev->event(dev, type, code, value);
 163                         break;
 164         }
 165
 166         if (type != EV_SYN)
 167                 dev->sync = 0;
 168
 169         if (dev->grab)
 170                 dev->grab->handler->event(dev->grab, type, code, value);
 171         else
 172                 list_for_each_entry(handle, &dev->h_list, d_node)
 173                         if (handle->open)
 174                                 handle->handler->event(handle, type, code, value);
 175 }
 176
 177 static void input_repeat_key(unsigned long data)
 178 {
 179         struct input_dev *dev = (void *) data;
 180
 181         if (!test_bit(dev->repeat_key, dev->key))
 182                 return;
 183
 184         input_event(dev, EV_KEY, dev->repeat_key, 2);
 185         input_sync(dev);
 186
 187         if (dev->rep[REP_PERIOD])
 188                 mod_timer(&dev->timer, jiffies + msecs_to_jiffies(dev->rep[REP_PERIOD]));
 189 }
 190
 191 int input_accept_process(struct input_handle *handle, struct file *file)
 192 {
 193         if (handle->dev->accept)
 194                 return handle->dev->accept(handle->dev, file);
 195
 196         return 0;
 197 }
 198
 199 int input_grab_device(struct input_handle *handle)
 200 {
 201         if (handle->dev->grab)
 202                 return -EBUSY;
 203
 204         handle->dev->grab = handle;
 205         return 0;
 206 }
 207
 208 void input_release_device(struct input_handle *handle)
 209 {
 210         if (handle->dev->grab == handle)
 211                 handle->dev->grab = NULL;
 212 }
 213
 214 int input_open_device(struct input_handle *handle)
 215 {
 216         struct input_dev *dev = handle->dev;
 217         int err;
 218
 219         err = down_interruptible(&dev->sem);
 220         if (err)
 221                 return err;
 222
 223         handle->open++;
 224
 225         if (!dev->users++ && dev->open)
 226                 err = dev->open(dev);
 227
 228         if (err)
 229                 handle->open--;
 230
 231         up(&dev->sem);
 232
 233         return err;
 234 }
 235
 236 int input_flush_device(struct input_handle* handle, struct file* file)
 237 {
 238         if (handle->dev->flush)
 239                 return handle->dev->flush(handle->dev, file);
 240
 241         return 0;
 242 }
 243
 244 void input_close_device(struct input_handle *handle)
 245 {
 246         struct input_dev *dev = handle->dev;
 247
 248         input_release_device(handle);
 249
 250         down(&dev->sem);
 251
 252         if (!--dev->users && dev->close)
 253                 dev->close(dev);
 254         handle->open--;
 255
 256         up(&dev->sem);
 257 }
 258
 259 static void input_link_handle(struct input_handle *handle)
 260 {
 261         list_add_tail(&handle->d_node, &handle->dev->h_list);
 262         list_add_tail(&handle->h_node, &handle->handler->h_list);
 263 }
 264
 265 #define MATCH_BIT(bit, max) \
 266                 for (i = 0; i < NBITS(max); i++) \
 267                         if ((id->bit[i] & dev->bit[i]) != id->bit[i]) \
 268                                 break; \
 269                 if (i != NBITS(max)) \
 270                         continue;
 271
 272 static struct input_device_id *input_match_device(struct input_device_id *id, struct input_dev *dev)
 273 {
 274         int i;
 275
 276         for (; id->flags || id->driver_info; id++) {
 277
 278                 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
 279                         if (id->id.bustype != dev->id.bustype)
 280                                 continue;
 281
 282                 if (id->flags & INPUT_DEVICE_ID_MATCH_VENDOR)
 283                         if (id->id.vendor != dev->id.vendor)
 284                                 continue;
 285
 286                 if (id->flags & INPUT_DEVICE_ID_MATCH_PRODUCT)
 287                         if (id->id.product != dev->id.product)
 288                                 continue;
 289
 290                 if (id->flags & INPUT_DEVICE_ID_MATCH_VERSION)
 291                         if (id->id.version != dev->id.version)
 292                                 continue;
 293
 294                 MATCH_BIT(evbit,  EV_MAX);
 295                 MATCH_BIT(keybit, KEY_MAX);
 296                 MATCH_BIT(relbit, REL_MAX);
 297                 MATCH_BIT(absbit, ABS_MAX);
 298                 MATCH_BIT(mscbit, MSC_MAX);
 299                 MATCH_BIT(ledbit, LED_MAX);
 300                 MATCH_BIT(sndbit, SND_MAX);
 301                 MATCH_BIT(ffbit,  FF_MAX);
 302
 303                 return id;
 304         }
 305
 306         return NULL;
 307 }
 308
 309
 310 /*
 311  * Input hotplugging interface - loading event handlers based on
 312  * device bitfields.
 313  */
 314
 315 #ifdef CONFIG_HOTPLUG
 316
 317 /*
 318  * Input hotplugging invokes what /proc/sys/kernel/hotplug says
 319  * (normally /sbin/hotplug) when input devices get added or removed.
 320  *
 321  * This invokes a user mode policy agent, typically helping to load driver
 322  * or other modules, configure the device, and more.  Drivers can provide
 323  * a MODULE_DEVICE_TABLE to help with module loading subtasks.
 324  *
 325  */
 326
 327 #define SPRINTF_BIT_A(bit, name, max) \
 328         do { \
 329                 envp[i++] = scratch; \
 330                 scratch += sprintf(scratch, name); \
 331                 for (j = NBITS(max) - 1; j >= 0; j--) \
 332                         if (dev->bit[j]) break; \
 333                 for (; j >= 0; j--) \
 334                         scratch += sprintf(scratch, "%lx ", dev->bit[j]); \
 335                 scratch++; \
 336         } while (0)
 337
 338 #define SPRINTF_BIT_A2(bit, name, max, ev) \
 339         do { \
 340                 if (test_bit(ev, dev->evbit)) \
 341                         SPRINTF_BIT_A(bit, name, max); \
 342         } while (0)
 343
 344 static void input_call_hotplug(char *verb, struct input_dev *dev)
 345 {
 346         char *argv[3], **envp, *buf, *scratch;
 347         int i = 0, j, value;
 348
 349         if (!hotplug_path[0]) {
 350                 printk(KERN_ERR "input.c: calling hotplug without a hotplug agent defined\n");
 351                 return;
 352         }
 353         if (in_interrupt()) {
 354                 printk(KERN_ERR "input.c: calling hotplug from interrupt\n");
 355                 return;
 356         }
 357         if (!current->fs->root) {
 358                 printk(KERN_WARNING "input.c: calling hotplug without valid filesystem\n");
 359                 return;
 360         }
 361         if (!(envp = (char **) kmalloc(20 * sizeof(char *), GFP_KERNEL))) {
 362                 printk(KERN_ERR "input.c: not enough memory allocating hotplug environment\n");
 363                 return;
 364         }
 365         if (!(buf = kmalloc(1024, GFP_KERNEL))) {
 366                 kfree (envp);
 367                 printk(KERN_ERR "input.c: not enough memory allocating hotplug environment\n");
 368                 return;
 369         }
 370
 371         argv[0] = hotplug_path;
 372         argv[1] = "input";
 373         argv[2] = NULL;
 374
 375         envp[i++] = "HOME=/";
 376         envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
 377
 378         scratch = buf;
 379
 380         envp[i++] = scratch;
 381         scratch += sprintf(scratch, "ACTION=%s", verb) + 1;
 382
 383         envp[i++] = scratch;
 384         scratch += sprintf(scratch, "PRODUCT=%x/%x/%x/%x",
 385                 dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version) + 1;
 386
 387         if (dev->name) {
 388                 envp[i++] = scratch;
 389                 scratch += sprintf(scratch, "NAME=%s", dev->name) + 1;
 390         }
 391
 392         if (dev->phys) {
 393                 envp[i++] = scratch;
 394                 scratch += sprintf(scratch, "PHYS=%s", dev->phys) + 1;
 395         }
 396
 397         SPRINTF_BIT_A(evbit, "EV=", EV_MAX);
 398         SPRINTF_BIT_A2(keybit, "KEY=", KEY_MAX, EV_KEY);
 399         SPRINTF_BIT_A2(relbit, "REL=", REL_MAX, EV_REL);
 400         SPRINTF_BIT_A2(absbit, "ABS=", ABS_MAX, EV_ABS);
 401         SPRINTF_BIT_A2(mscbit, "MSC=", MSC_MAX, EV_MSC);
 402         SPRINTF_BIT_A2(ledbit, "LED=", LED_MAX, EV_LED);
 403         SPRINTF_BIT_A2(sndbit, "SND=", SND_MAX, EV_SND);
 404         SPRINTF_BIT_A2(ffbit,  "FF=",  FF_MAX, EV_FF);
 405
 406         envp[i++] = NULL;
 407
 408 #ifdef INPUT_DEBUG
 409         printk(KERN_DEBUG "input.c: calling %s %s [%s %s %s %s %s]\n",
 410                 argv[0], argv[1], envp[0], envp[1], envp[2], envp[3], envp[4]);
 411 #endif
 412
 413         value = call_usermodehelper(argv [0], argv, envp, 0);
 414
 415         kfree(buf);
 416         kfree(envp);
 417
 418 #ifdef INPUT_DEBUG
 419         if (value != 0)
 420                 printk(KERN_DEBUG "input.c: hotplug returned %d\n", value);
 421 #endif
 422 }
 423
 424 #endif
 425
 426 #ifdef CONFIG_PROC_FS
 427
 428 static struct proc_dir_entry *proc_bus_input_dir;
 429 static DECLARE_WAIT_QUEUE_HEAD(input_devices_poll_wait);
 430 static int input_devices_state;
 431
 432 static inline void input_wakeup_procfs_readers(void)
 433 {
 434         input_devices_state++;
 435         wake_up(&input_devices_poll_wait);
 436 }
 437
 438 static unsigned int input_devices_poll(struct file *file, poll_table *wait)
 439 {
 440         int state = input_devices_state;
 441         poll_wait(file, &input_devices_poll_wait, wait);
 442         if (state != input_devices_state)
 443                 return POLLIN | POLLRDNORM;
 444         return 0;
 445 }
 446
 447 #define SPRINTF_BIT_B(bit, name, max) \
 448         do { \
 449                 len += sprintf(buf + len, "B: %s", name); \
 450                 for (i = NBITS(max) - 1; i >= 0; i--) \
 451                         if (dev->bit[i]) break; \
 452                 for (; i >= 0; i--) \
 453                         len += sprintf(buf + len, "%lx ", dev->bit[i]); \
 454                 len += sprintf(buf + len, "\n"); \
 455         } while (0)
 456
 457 #define SPRINTF_BIT_B2(bit, name, max, ev) \
 458         do { \
 459                 if (test_bit(ev, dev->evbit)) \
 460                         SPRINTF_BIT_B(bit, name, max); \
 461         } while (0)
 462
 463 static int input_devices_read(char *buf, char **start, off_t pos, int count, int *eof, void *data)
 464 {
 465         struct input_dev *dev;
 466         struct input_handle *handle;
 467
 468         off_t at = 0;
 469         int i, len, cnt = 0;
 470
 471         list_for_each_entry(dev, &input_dev_list, node) {
 472
 473                 len = sprintf(buf, "I: Bus=%04x Vendor=%04x Product=%04x Version=%04x\n",
 474                         dev->id.bustype, dev->id.vendor, dev->id.product, dev->id.version);
 475
 476                 len += sprintf(buf + len, "N: Name=\"%s\"\n", dev->name ? dev->name : "");
 477                 len += sprintf(buf + len, "P: Phys=%s\n", dev->phys ? dev->phys : "");
 478                 len += sprintf(buf + len, "H: Handlers=");
 479
 480                 list_for_each_entry(handle, &dev->h_list, d_node)
 481                         len += sprintf(buf + len, "%s ", handle->name);
 482
 483                 len += sprintf(buf + len, "\n");
 484
 485                 SPRINTF_BIT_B(evbit, "EV=", EV_MAX);
 486                 SPRINTF_BIT_B2(keybit, "KEY=", KEY_MAX, EV_KEY);
 487                 SPRINTF_BIT_B2(relbit, "REL=", REL_MAX, EV_REL);
 488                 SPRINTF_BIT_B2(absbit, "ABS=", ABS_MAX, EV_ABS);
 489                 SPRINTF_BIT_B2(mscbit, "MSC=", MSC_MAX, EV_MSC);
 490                 SPRINTF_BIT_B2(ledbit, "LED=", LED_MAX, EV_LED);
 491                 SPRINTF_BIT_B2(sndbit, "SND=", SND_MAX, EV_SND);
 492                 SPRINTF_BIT_B2(ffbit,  "FF=",  FF_MAX, EV_FF);
 493
 494                 len += sprintf(buf + len, "\n");
 495
 496                 at += len;
 497
 498                 if (at >= pos) {
 499                         if (!*start) {
 500                                 *start = buf + (pos - (at - len));
 501                                 cnt = at - pos;
 502                         } else  cnt += len;
 503                         buf += len;
 504                         if (cnt >= count)
 505                                 break;
 506                 }
 507         }
 508
 509         if (&dev->node == &input_dev_list)
 510                 *eof = 1;
 511
 512         return (count > cnt) ? cnt : count;
 513 }
 514
 515 static int input_handlers_read(char *buf, char **start, off_t pos, int count, int *eof, void *data)
 516 {
 517         struct input_handler *handler;
 518
 519         off_t at = 0;
 520         int len = 0, cnt = 0;
 521         int i = 0;
 522
 523         list_for_each_entry(handler, &input_handler_list, node) {
 524
 525                 if (handler->fops)
 526                         len = sprintf(buf, "N: Number=%d Name=%s Minor=%d\n",
 527                                 i++, handler->name, handler->minor);
 528                 else
 529                         len = sprintf(buf, "N: Number=%d Name=%s\n",
 530                                 i++, handler->name);
 531
 532                 at += len;
 533
 534                 if (at >= pos) {
 535                         if (!*start) {
 536                                 *start = buf + (pos - (at - len));
 537                                 cnt = at - pos;
 538                         } else  cnt += len;
 539                         buf += len;
 540                         if (cnt >= count)
 541                                 break;
 542                 }
 543         }
 544         if (&handler->node == &input_handler_list)
 545                 *eof = 1;
 546
 547         return (count > cnt) ? cnt : count;
 548 }
 549
 550 static struct file_operations input_fileops;
 551
 552 static int __init input_proc_init(void)
 553 {
 554         struct proc_dir_entry *entry;
 555
 556         proc_bus_input_dir = proc_mkdir("input", proc_bus);
 557         if (!proc_bus_input_dir)
 558                 return -ENOMEM;
 559
 560         proc_bus_input_dir->owner = THIS_MODULE;
 561
 562         entry = create_proc_read_entry("devices", 0, proc_bus_input_dir, input_devices_read, NULL);
 563         if (!entry)
 564                 goto fail1;
 565
 566         entry->owner = THIS_MODULE;
 567         input_fileops = *entry->proc_fops;
 568         entry->proc_fops = &input_fileops;
 569         entry->proc_fops->poll = input_devices_poll;
 570
 571         entry = create_proc_read_entry("handlers", 0, proc_bus_input_dir, input_handlers_read, NULL);
 572         if (!entry)
 573                 goto fail2;
 574
 575         entry->owner = THIS_MODULE;
 576
 577         return 0;
 578
 579  fail2: remove_proc_entry("devices", proc_bus_input_dir);
 580  fail1: remove_proc_entry("input", proc_bus);
 581         return -ENOMEM;
 582 }
 583
 584 static void input_proc_exit(void)
 585 {
 586         remove_proc_entry("devices", proc_bus_input_dir);
 587         remove_proc_entry("handlers", proc_bus_input_dir);
 588         remove_proc_entry("input", proc_bus);
 589 }
 590
 591 #else /* !CONFIG_PROC_FS */
 592 static inline void input_wakeup_procfs_readers(void) { }
 593 static inline int input_proc_init(void) { return 0; }
 594 static inline void input_proc_exit(void) { }
 595 #endif
 596
 597 void input_register_device(struct input_dev *dev)
 598 {
 599         struct input_handle *handle;
 600         struct input_handler *handler;
 601         struct input_device_id *id;
 602
 603         set_bit(EV_SYN, dev->evbit);
 604
 605         init_MUTEX(&dev->sem);
 606
 607         /*
 608          * If delay and period are pre-set by the driver, then autorepeating
 609          * is handled by the driver itself and we don't do it in input.c.
 610          */
 611
 612         init_timer(&dev->timer);
 613         if (!dev->rep[REP_DELAY] && !dev->rep[REP_PERIOD]) {
 614                 dev->timer.data = (long) dev;
 615                 dev->timer.function = input_repeat_key;
 616                 dev->rep[REP_DELAY] = 250;
 617                 dev->rep[REP_PERIOD] = 33;
 618         }
 619
 620         INIT_LIST_HEAD(&dev->h_list);
 621         list_add_tail(&dev->node, &input_dev_list);
 622
 623         list_for_each_entry(handler, &input_handler_list, node)
 624                 if (!handler->blacklist || !input_match_device(handler->blacklist, dev))
 625                         if ((id = input_match_device(handler->id_table, dev)))
 626                                 if ((handle = handler->connect(handler, dev, id)))
 627                                         input_link_handle(handle);
 628
 629 #ifdef CONFIG_HOTPLUG
 630         input_call_hotplug("add", dev);
 631 #endif
 632
 633         input_wakeup_procfs_readers();
 634 }
 635
 636 void input_unregister_device(struct input_dev *dev)
 637 {
 638         struct list_head * node, * next;
 639
 640         if (!dev) return;
 641
 642         del_timer_sync(&dev->timer);
 643
 644         list_for_each_safe(node, next, &dev->h_list) {
 645                 struct input_handle * handle = to_handle(node);
 646                 list_del_init(&handle->d_node);
 647                 list_del_init(&handle->h_node);
 648                 handle->handler->disconnect(handle);
 649         }
 650
 651 #ifdef CONFIG_HOTPLUG
 652         input_call_hotplug("remove", dev);
 653 #endif
 654
 655         list_del_init(&dev->node);
 656
 657         input_wakeup_procfs_readers();
 658 }
 659
 660 void input_register_handler(struct input_handler *handler)
 661 {
 662         struct input_dev *dev;
 663         struct input_handle *handle;
 664         struct input_device_id *id;
 665
 666         if (!handler) return;
 667
 668         INIT_LIST_HEAD(&handler->h_list);
 669
 670         if (handler->fops != NULL)
 671                 input_table[handler->minor >> 5] = handler;
 672
 673         list_add_tail(&handler->node, &input_handler_list);
 674
 675         list_for_each_entry(dev, &input_dev_list, node)
 676                 if (!handler->blacklist || !input_match_device(handler->blacklist, dev))
 677                         if ((id = input_match_device(handler->id_table, dev)))
 678                                 if ((handle = handler->connect(handler, dev, id)))
 679                                         input_link_handle(handle);
 680
 681         input_wakeup_procfs_readers();
 682 }
 683
 684 void input_unregister_handler(struct input_handler *handler)
 685 {
 686         struct list_head * node, * next;
 687
 688         list_for_each_safe(node, next, &handler->h_list) {
 689                 struct input_handle * handle = to_handle_h(node);
 690                 list_del_init(&handle->h_node);
 691                 list_del_init(&handle->d_node);
 692                 handler->disconnect(handle);
 693         }
 694
 695         list_del_init(&handler->node);
 696
 697         if (handler->fops != NULL)
 698                 input_table[handler->minor >> 5] = NULL;
 699
 700         input_wakeup_procfs_readers();
 701 }
 702
 703 static int input_open_file(struct inode *inode, struct file *file)
 704 {
 705         struct input_handler *handler = input_table[iminor(inode) >> 5];
 706         struct file_operations *old_fops, *new_fops = NULL;
 707         int err;
 708
 709         /* No load-on-demand here? */
 710         if (!handler || !(new_fops = fops_get(handler->fops)))
 711                 return -ENODEV;
 712
 713         /*
 714          * That's _really_ odd. Usually NULL ->open means "nothing special",
 715          * not "no device". Oh, well...
 716          */
 717         if (!new_fops->open) {
 718                 fops_put(new_fops);
 719                 return -ENODEV;
 720         }
 721         old_fops = file->f_op;
 722         file->f_op = new_fops;
 723
 724         err = new_fops->open(inode, file);
 725
 726         if (err) {
 727                 fops_put(file->f_op);
 728                 file->f_op = fops_get(old_fops);
 729         }
 730         fops_put(old_fops);
 731         return err;
 732 }
 733
 734 static struct file_operations input_fops = {
 735         .owner = THIS_MODULE,
 736         .open = input_open_file,
 737 };
 738
 739 struct class *input_class;
 740
 741 static int __init input_init(void)
 742 {
 743         int err;
 744
 745         input_class = class_create(THIS_MODULE, "input");
 746         if (IS_ERR(input_class)) {
 747                 printk(KERN_ERR "input: unable to register input class\n");
 748                 return PTR_ERR(input_class);
 749         }
 750
 751         err = input_proc_init();
 752         if (err)
 753                 goto fail1;
 754
 755         err = register_chrdev(INPUT_MAJOR, "input", &input_fops);
 756         if (err) {
 757                 printk(KERN_ERR "input: unable to register char major %d", INPUT_MAJOR);
 758                 goto fail2;
 759         }
 760
 761         err = devfs_mk_dir("input");
 762         if (err)
 763                 goto fail3;
 764
 765         return 0;
 766
 767  fail3: unregister_chrdev(INPUT_MAJOR, "input");
 768  fail2: input_proc_exit();
 769  fail1: class_destroy(input_class);
 770         return err;
 771 }
 772
 773 static void __exit input_exit(void)
 774 {
 775         input_proc_exit();
 776         devfs_remove("input");
 777         unregister_chrdev(INPUT_MAJOR, "input");
 778         class_destroy(input_class);
 779 }
 780
 781 subsys_initcall(input_init);
 782 module_exit(input_exit);