1 /* 2 * Event char devices, giving access to raw input device events. 3 * 4 * Copyright (c) 1999-2002 Vojtech Pavlik 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 as published by 8 * the Free Software Foundation. 9 */ 10 11 #define EVDEV_MINOR_BASE 64 12 #define EVDEV_MINORS 32 13 #define EVDEV_BUFFER_SIZE 64 14 15 #include <linux/poll.h> 16 #include <linux/slab.h> 17 #include <linux/module.h> 18 #include <linux/init.h> 19 #include <linux/input.h> 20 #include <linux/major.h> 21 #include <linux/device.h> 22 #include "input-compat.h" 23 24 struct evdev { 25 int exist; 26 int open; 27 int minor; 28 char name[16]; 29 struct input_handle handle; 30 wait_queue_head_t wait; 31 struct evdev_client *grab; 32 struct list_head client_list; 33 spinlock_t client_lock; /* protects client_list */ 34 struct mutex mutex; 35 struct device dev; 36 }; 37 38 struct evdev_client { 39 struct input_event buffer[EVDEV_BUFFER_SIZE]; 40 int head; 41 int tail; 42 spinlock_t buffer_lock; /* protects access to buffer, head and tail */ 43 struct fasync_struct *fasync; 44 struct evdev *evdev; 45 struct list_head node; 46 }; 47 48 static struct evdev *evdev_table[EVDEV_MINORS]; 49 static DEFINE_MUTEX(evdev_table_mutex); 50 51 static void evdev_pass_event(struct evdev_client *client, 52 struct input_event *event) 53 { 54 /* 55 * Interrupts are disabled, just acquire the lock 56 */ 57 spin_lock(&client->buffer_lock); 58 client->buffer[client->head++] = *event; 59 client->head &= EVDEV_BUFFER_SIZE - 1; 60 spin_unlock(&client->buffer_lock); 61 62 kill_fasync(&client->fasync, SIGIO, POLL_IN); 63 } 64 65 /* 66 * Pass incoming event to all connected clients. 67 */ 68 static void evdev_event(struct input_handle *handle, 69 unsigned int type, unsigned int code, int value) 70 { 71 struct evdev *evdev = handle->private; 72 struct evdev_client *client; 73 struct input_event event; 74 75 do_gettimeofday(&event.time); 76 event.type = type; 77 event.code = code; 78 event.value = value; 79 80 rcu_read_lock(); 81 82 client = rcu_dereference(evdev->grab); 83 if (client) 84 evdev_pass_event(client, &event); 85 else 86 list_for_each_entry_rcu(client, &evdev->client_list, node) 87 evdev_pass_event(client, &event); 88 89 rcu_read_unlock(); 90 91 wake_up_interruptible(&evdev->wait); 92 } 93 94 static int evdev_fasync(int fd, struct file *file, int on) 95 { 96 struct evdev_client *client = file->private_data; 97 int retval; 98 99 retval = fasync_helper(fd, file, on, &client->fasync); 100 101 return retval < 0 ? retval : 0; 102 } 103 104 static int evdev_flush(struct file *file, fl_owner_t id) 105 { 106 struct evdev_client *client = file->private_data; 107 struct evdev *evdev = client->evdev; 108 int retval; 109 110 retval = mutex_lock_interruptible(&evdev->mutex); 111 if (retval) 112 return retval; 113 114 if (!evdev->exist) 115 retval = -ENODEV; 116 else 117 retval = input_flush_device(&evdev->handle, file); 118 119 mutex_unlock(&evdev->mutex); 120 return retval; 121 } 122 123 static void evdev_free(struct device *dev) 124 { 125 struct evdev *evdev = container_of(dev, struct evdev, dev); 126 127 input_put_device(evdev->handle.dev); 128 kfree(evdev); 129 } 130 131 /* 132 * Grabs an event device (along with underlying input device). 133 * This function is called with evdev->mutex taken. 134 */ 135 static int evdev_grab(struct evdev *evdev, struct evdev_client *client) 136 { 137 int error; 138 139 if (evdev->grab) 140 return -EBUSY; 141 142 error = input_grab_device(&evdev->handle); 143 if (error) 144 return error; 145 146 rcu_assign_pointer(evdev->grab, client); 147 synchronize_rcu(); 148 149 return 0; 150 } 151 152 static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client) 153 { 154 if (evdev->grab != client) 155 return -EINVAL; 156 157 rcu_assign_pointer(evdev->grab, NULL); 158 synchronize_rcu(); 159 input_release_device(&evdev->handle); 160 161 return 0; 162 } 163 164 static void evdev_attach_client(struct evdev *evdev, 165 struct evdev_client *client) 166 { 167 spin_lock(&evdev->client_lock); 168 list_add_tail_rcu(&client->node, &evdev->client_list); 169 spin_unlock(&evdev->client_lock); 170 synchronize_rcu(); 171 } 172 173 static void evdev_detach_client(struct evdev *evdev, 174 struct evdev_client *client) 175 { 176 spin_lock(&evdev->client_lock); 177 list_del_rcu(&client->node); 178 spin_unlock(&evdev->client_lock); 179 synchronize_rcu(); 180 } 181 182 static int evdev_open_device(struct evdev *evdev) 183 { 184 int retval; 185 186 retval = mutex_lock_interruptible(&evdev->mutex); 187 if (retval) 188 return retval; 189 190 if (!evdev->exist) 191 retval = -ENODEV; 192 else if (!evdev->open++) { 193 retval = input_open_device(&evdev->handle); 194 if (retval) 195 evdev->open--; 196 } 197 198 mutex_unlock(&evdev->mutex); 199 return retval; 200 } 201 202 static void evdev_close_device(struct evdev *evdev) 203 { 204 mutex_lock(&evdev->mutex); 205 206 if (evdev->exist && !--evdev->open) 207 input_close_device(&evdev->handle); 208 209 mutex_unlock(&evdev->mutex); 210 } 211 212 /* 213 * Wake up users waiting for IO so they can disconnect from 214 * dead device. 215 */ 216 static void evdev_hangup(struct evdev *evdev) 217 { 218 struct evdev_client *client; 219 220 spin_lock(&evdev->client_lock); 221 list_for_each_entry(client, &evdev->client_list, node) 222 kill_fasync(&client->fasync, SIGIO, POLL_HUP); 223 spin_unlock(&evdev->client_lock); 224 225 wake_up_interruptible(&evdev->wait); 226 } 227 228 static int evdev_release(struct inode *inode, struct file *file) 229 { 230 struct evdev_client *client = file->private_data; 231 struct evdev *evdev = client->evdev; 232 233 mutex_lock(&evdev->mutex); 234 if (evdev->grab == client) 235 evdev_ungrab(evdev, client); 236 mutex_unlock(&evdev->mutex); 237 238 evdev_detach_client(evdev, client); 239 kfree(client); 240 241 evdev_close_device(evdev); 242 put_device(&evdev->dev); 243 244 return 0; 245 } 246 247 static int evdev_open(struct inode *inode, struct file *file) 248 { 249 struct evdev *evdev; 250 struct evdev_client *client; 251 int i = iminor(inode) - EVDEV_MINOR_BASE; 252 int error; 253 254 if (i >= EVDEV_MINORS) 255 return -ENODEV; 256 257 error = mutex_lock_interruptible(&evdev_table_mutex); 258 if (error) 259 return error; 260 evdev = evdev_table[i]; 261 if (evdev) 262 get_device(&evdev->dev); 263 mutex_unlock(&evdev_table_mutex); 264 265 if (!evdev) 266 return -ENODEV; 267 268 client = kzalloc(sizeof(struct evdev_client), GFP_KERNEL); 269 if (!client) { 270 error = -ENOMEM; 271 goto err_put_evdev; 272 } 273 274 spin_lock_init(&client->buffer_lock); 275 client->evdev = evdev; 276 evdev_attach_client(evdev, client); 277 278 error = evdev_open_device(evdev); 279 if (error) 280 goto err_free_client; 281 282 file->private_data = client; 283 return 0; 284 285 err_free_client: 286 evdev_detach_client(evdev, client); 287 kfree(client); 288 err_put_evdev: 289 put_device(&evdev->dev); 290 return error; 291 } 292 293 static ssize_t evdev_write(struct file *file, const char __user *buffer, 294 size_t count, loff_t *ppos) 295 { 296 struct evdev_client *client = file->private_data; 297 struct evdev *evdev = client->evdev; 298 struct input_event event; 299 int retval; 300 301 retval = mutex_lock_interruptible(&evdev->mutex); 302 if (retval) 303 return retval; 304 305 if (!evdev->exist) { 306 retval = -ENODEV; 307 goto out; 308 } 309 310 while (retval < count) { 311 312 if (input_event_from_user(buffer + retval, &event)) { 313 retval = -EFAULT; 314 goto out; 315 } 316 317 input_inject_event(&evdev->handle, 318 event.type, event.code, event.value); 319 retval += input_event_size(); 320 } 321 322 out: 323 mutex_unlock(&evdev->mutex); 324 return retval; 325 } 326 327 static int evdev_fetch_next_event(struct evdev_client *client, 328 struct input_event *event) 329 { 330 int have_event; 331 332 spin_lock_irq(&client->buffer_lock); 333 334 have_event = client->head != client->tail; 335 if (have_event) { 336 *event = client->buffer[client->tail++]; 337 client->tail &= EVDEV_BUFFER_SIZE - 1; 338 } 339 340 spin_unlock_irq(&client->buffer_lock); 341 342 return have_event; 343 } 344 345 static ssize_t evdev_read(struct file *file, char __user *buffer, 346 size_t count, loff_t *ppos) 347 { 348 struct evdev_client *client = file->private_data; 349 struct evdev *evdev = client->evdev; 350 struct input_event event; 351 int retval; 352 353 if (count < input_event_size()) 354 return -EINVAL; 355 356 if (client->head == client->tail && evdev->exist && 357 (file->f_flags & O_NONBLOCK)) 358 return -EAGAIN; 359 360 retval = wait_event_interruptible(evdev->wait, 361 client->head != client->tail || !evdev->exist); 362 if (retval) 363 return retval; 364 365 if (!evdev->exist) 366 return -ENODEV; 367 368 while (retval + input_event_size() <= count && 369 evdev_fetch_next_event(client, &event)) { 370 371 if (input_event_to_user(buffer + retval, &event)) 372 return -EFAULT; 373 374 retval += input_event_size(); 375 } 376 377 return retval; 378 } 379 380 /* No kernel lock - fine */ 381 static unsigned int evdev_poll(struct file *file, poll_table *wait) 382 { 383 struct evdev_client *client = file->private_data; 384 struct evdev *evdev = client->evdev; 385 386 poll_wait(file, &evdev->wait, wait); 387 return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) | 388 (evdev->exist ? 0 : (POLLHUP | POLLERR)); 389 } 390 391 #ifdef CONFIG_COMPAT 392 393 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8) 394 #define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1) 395 396 #ifdef __BIG_ENDIAN 397 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 398 unsigned int maxlen, void __user *p, int compat) 399 { 400 int len, i; 401 402 if (compat) { 403 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t); 404 if (len > maxlen) 405 len = maxlen; 406 407 for (i = 0; i < len / sizeof(compat_long_t); i++) 408 if (copy_to_user((compat_long_t __user *) p + i, 409 (compat_long_t *) bits + 410 i + 1 - ((i % 2) << 1), 411 sizeof(compat_long_t))) 412 return -EFAULT; 413 } else { 414 len = BITS_TO_LONGS(maxbit) * sizeof(long); 415 if (len > maxlen) 416 len = maxlen; 417 418 if (copy_to_user(p, bits, len)) 419 return -EFAULT; 420 } 421 422 return len; 423 } 424 #else 425 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 426 unsigned int maxlen, void __user *p, int compat) 427 { 428 int len = compat ? 429 BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) : 430 BITS_TO_LONGS(maxbit) * sizeof(long); 431 432 if (len > maxlen) 433 len = maxlen; 434 435 return copy_to_user(p, bits, len) ? -EFAULT : len; 436 } 437 #endif /* __BIG_ENDIAN */ 438 439 #else 440 441 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 442 unsigned int maxlen, void __user *p, int compat) 443 { 444 int len = BITS_TO_LONGS(maxbit) * sizeof(long); 445 446 if (len > maxlen) 447 len = maxlen; 448 449 return copy_to_user(p, bits, len) ? -EFAULT : len; 450 } 451 452 #endif /* CONFIG_COMPAT */ 453 454 static int str_to_user(const char *str, unsigned int maxlen, void __user *p) 455 { 456 int len; 457 458 if (!str) 459 return -ENOENT; 460 461 len = strlen(str) + 1; 462 if (len > maxlen) 463 len = maxlen; 464 465 return copy_to_user(p, str, len) ? -EFAULT : len; 466 } 467 468 #define OLD_KEY_MAX 0x1ff 469 static int handle_eviocgbit(struct input_dev *dev, unsigned int cmd, void __user *p, int compat_mode) 470 { 471 static unsigned long keymax_warn_time; 472 unsigned long *bits; 473 int len; 474 475 switch (_IOC_NR(cmd) & EV_MAX) { 476 477 case 0: bits = dev->evbit; len = EV_MAX; break; 478 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break; 479 case EV_REL: bits = dev->relbit; len = REL_MAX; break; 480 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break; 481 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break; 482 case EV_LED: bits = dev->ledbit; len = LED_MAX; break; 483 case EV_SND: bits = dev->sndbit; len = SND_MAX; break; 484 case EV_FF: bits = dev->ffbit; len = FF_MAX; break; 485 case EV_SW: bits = dev->swbit; len = SW_MAX; break; 486 default: return -EINVAL; 487 } 488 489 /* 490 * Work around bugs in userspace programs that like to do 491 * EVIOCGBIT(EV_KEY, KEY_MAX) and not realize that 'len' 492 * should be in bytes, not in bits. 493 */ 494 if ((_IOC_NR(cmd) & EV_MAX) == EV_KEY && _IOC_SIZE(cmd) == OLD_KEY_MAX) { 495 len = OLD_KEY_MAX; 496 if (printk_timed_ratelimit(&keymax_warn_time, 10 * 1000)) 497 printk(KERN_WARNING 498 "evdev.c(EVIOCGBIT): Suspicious buffer size %u, " 499 "limiting output to %zu bytes. See " 500 "http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n", 501 OLD_KEY_MAX, 502 BITS_TO_LONGS(OLD_KEY_MAX) * sizeof(long)); 503 } 504 505 return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode); 506 } 507 #undef OLD_KEY_MAX 508 509 static long evdev_do_ioctl(struct file *file, unsigned int cmd, 510 void __user *p, int compat_mode) 511 { 512 struct evdev_client *client = file->private_data; 513 struct evdev *evdev = client->evdev; 514 struct input_dev *dev = evdev->handle.dev; 515 struct input_absinfo abs; 516 struct ff_effect effect; 517 int __user *ip = (int __user *)p; 518 int i, t, u, v; 519 int error; 520 521 switch (cmd) { 522 523 case EVIOCGVERSION: 524 return put_user(EV_VERSION, ip); 525 526 case EVIOCGID: 527 if (copy_to_user(p, &dev->id, sizeof(struct input_id))) 528 return -EFAULT; 529 return 0; 530 531 case EVIOCGREP: 532 if (!test_bit(EV_REP, dev->evbit)) 533 return -ENOSYS; 534 if (put_user(dev->rep[REP_DELAY], ip)) 535 return -EFAULT; 536 if (put_user(dev->rep[REP_PERIOD], ip + 1)) 537 return -EFAULT; 538 return 0; 539 540 case EVIOCSREP: 541 if (!test_bit(EV_REP, dev->evbit)) 542 return -ENOSYS; 543 if (get_user(u, ip)) 544 return -EFAULT; 545 if (get_user(v, ip + 1)) 546 return -EFAULT; 547 548 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u); 549 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v); 550 551 return 0; 552 553 case EVIOCGKEYCODE: 554 if (get_user(t, ip)) 555 return -EFAULT; 556 557 error = input_get_keycode(dev, t, &v); 558 if (error) 559 return error; 560 561 if (put_user(v, ip + 1)) 562 return -EFAULT; 563 564 return 0; 565 566 case EVIOCSKEYCODE: 567 if (get_user(t, ip) || get_user(v, ip + 1)) 568 return -EFAULT; 569 570 return input_set_keycode(dev, t, v); 571 572 case EVIOCRMFF: 573 return input_ff_erase(dev, (int)(unsigned long) p, file); 574 575 case EVIOCGEFFECTS: 576 i = test_bit(EV_FF, dev->evbit) ? 577 dev->ff->max_effects : 0; 578 if (put_user(i, ip)) 579 return -EFAULT; 580 return 0; 581 582 case EVIOCGRAB: 583 if (p) 584 return evdev_grab(evdev, client); 585 else 586 return evdev_ungrab(evdev, client); 587 588 default: 589 590 if (_IOC_TYPE(cmd) != 'E') 591 return -EINVAL; 592 593 if (_IOC_DIR(cmd) == _IOC_READ) { 594 595 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0))) 596 return handle_eviocgbit(dev, cmd, p, compat_mode); 597 598 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0))) 599 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd), 600 p, compat_mode); 601 602 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0))) 603 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd), 604 p, compat_mode); 605 606 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0))) 607 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd), 608 p, compat_mode); 609 610 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0))) 611 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd), 612 p, compat_mode); 613 614 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) 615 return str_to_user(dev->name, _IOC_SIZE(cmd), p); 616 617 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) 618 return str_to_user(dev->phys, _IOC_SIZE(cmd), p); 619 620 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) 621 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p); 622 623 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) { 624 625 t = _IOC_NR(cmd) & ABS_MAX; 626 627 abs.value = dev->abs[t]; 628 abs.minimum = dev->absmin[t]; 629 abs.maximum = dev->absmax[t]; 630 abs.fuzz = dev->absfuzz[t]; 631 abs.flat = dev->absflat[t]; 632 633 if (copy_to_user(p, &abs, sizeof(struct input_absinfo))) 634 return -EFAULT; 635 636 return 0; 637 } 638 639 } 640 641 if (_IOC_DIR(cmd) == _IOC_WRITE) { 642 643 if (_IOC_NR(cmd) == _IOC_NR(EVIOCSFF)) { 644 645 if (input_ff_effect_from_user(p, _IOC_SIZE(cmd), &effect)) 646 return -EFAULT; 647 648 error = input_ff_upload(dev, &effect, file); 649 650 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id))) 651 return -EFAULT; 652 653 return error; 654 } 655 656 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) { 657 658 t = _IOC_NR(cmd) & ABS_MAX; 659 660 if (copy_from_user(&abs, p, 661 sizeof(struct input_absinfo))) 662 return -EFAULT; 663 664 /* 665 * Take event lock to ensure that we are not 666 * changing device parameters in the middle 667 * of event. 668 */ 669 spin_lock_irq(&dev->event_lock); 670 671 dev->abs[t] = abs.value; 672 dev->absmin[t] = abs.minimum; 673 dev->absmax[t] = abs.maximum; 674 dev->absfuzz[t] = abs.fuzz; 675 dev->absflat[t] = abs.flat; 676 677 spin_unlock_irq(&dev->event_lock); 678 679 return 0; 680 } 681 } 682 } 683 return -EINVAL; 684 } 685 686 static long evdev_ioctl_handler(struct file *file, unsigned int cmd, 687 void __user *p, int compat_mode) 688 { 689 struct evdev_client *client = file->private_data; 690 struct evdev *evdev = client->evdev; 691 int retval; 692 693 retval = mutex_lock_interruptible(&evdev->mutex); 694 if (retval) 695 return retval; 696 697 if (!evdev->exist) { 698 retval = -ENODEV; 699 goto out; 700 } 701 702 retval = evdev_do_ioctl(file, cmd, p, compat_mode); 703 704 out: 705 mutex_unlock(&evdev->mutex); 706 return retval; 707 } 708 709 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 710 { 711 return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0); 712 } 713 714 #ifdef CONFIG_COMPAT 715 static long evdev_ioctl_compat(struct file *file, 716 unsigned int cmd, unsigned long arg) 717 { 718 return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1); 719 } 720 #endif 721 722 static const struct file_operations evdev_fops = { 723 .owner = THIS_MODULE, 724 .read = evdev_read, 725 .write = evdev_write, 726 .poll = evdev_poll, 727 .open = evdev_open, 728 .release = evdev_release, 729 .unlocked_ioctl = evdev_ioctl, 730 #ifdef CONFIG_COMPAT 731 .compat_ioctl = evdev_ioctl_compat, 732 #endif 733 .fasync = evdev_fasync, 734 .flush = evdev_flush 735 }; 736 737 static int evdev_install_chrdev(struct evdev *evdev) 738 { 739 /* 740 * No need to do any locking here as calls to connect and 741 * disconnect are serialized by the input core 742 */ 743 evdev_table[evdev->minor] = evdev; 744 return 0; 745 } 746 747 static void evdev_remove_chrdev(struct evdev *evdev) 748 { 749 /* 750 * Lock evdev table to prevent race with evdev_open() 751 */ 752 mutex_lock(&evdev_table_mutex); 753 evdev_table[evdev->minor] = NULL; 754 mutex_unlock(&evdev_table_mutex); 755 } 756 757 /* 758 * Mark device non-existent. This disables writes, ioctls and 759 * prevents new users from opening the device. Already posted 760 * blocking reads will stay, however new ones will fail. 761 */ 762 static void evdev_mark_dead(struct evdev *evdev) 763 { 764 mutex_lock(&evdev->mutex); 765 evdev->exist = 0; 766 mutex_unlock(&evdev->mutex); 767 } 768 769 static void evdev_cleanup(struct evdev *evdev) 770 { 771 struct input_handle *handle = &evdev->handle; 772 773 evdev_mark_dead(evdev); 774 evdev_hangup(evdev); 775 evdev_remove_chrdev(evdev); 776 777 /* evdev is marked dead so no one else accesses evdev->open */ 778 if (evdev->open) { 779 input_flush_device(handle, NULL); 780 input_close_device(handle); 781 } 782 } 783 784 /* 785 * Create new evdev device. Note that input core serializes calls 786 * to connect and disconnect so we don't need to lock evdev_table here. 787 */ 788 static int evdev_connect(struct input_handler *handler, struct input_dev *dev, 789 const struct input_device_id *id) 790 { 791 struct evdev *evdev; 792 int minor; 793 int error; 794 795 for (minor = 0; minor < EVDEV_MINORS; minor++) 796 if (!evdev_table[minor]) 797 break; 798 799 if (minor == EVDEV_MINORS) { 800 printk(KERN_ERR "evdev: no more free evdev devices\n"); 801 return -ENFILE; 802 } 803 804 evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL); 805 if (!evdev) 806 return -ENOMEM; 807 808 INIT_LIST_HEAD(&evdev->client_list); 809 spin_lock_init(&evdev->client_lock); 810 mutex_init(&evdev->mutex); 811 init_waitqueue_head(&evdev->wait); 812 813 snprintf(evdev->name, sizeof(evdev->name), "event%d", minor); 814 evdev->exist = 1; 815 evdev->minor = minor; 816 817 evdev->handle.dev = input_get_device(dev); 818 evdev->handle.name = evdev->name; 819 evdev->handle.handler = handler; 820 evdev->handle.private = evdev; 821 822 dev_set_name(&evdev->dev, evdev->name); 823 evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor); 824 evdev->dev.class = &input_class; 825 evdev->dev.parent = &dev->dev; 826 evdev->dev.release = evdev_free; 827 device_initialize(&evdev->dev); 828 829 error = input_register_handle(&evdev->handle); 830 if (error) 831 goto err_free_evdev; 832 833 error = evdev_install_chrdev(evdev); 834 if (error) 835 goto err_unregister_handle; 836 837 error = device_add(&evdev->dev); 838 if (error) 839 goto err_cleanup_evdev; 840 841 return 0; 842 843 err_cleanup_evdev: 844 evdev_cleanup(evdev); 845 err_unregister_handle: 846 input_unregister_handle(&evdev->handle); 847 err_free_evdev: 848 put_device(&evdev->dev); 849 return error; 850 } 851 852 static void evdev_disconnect(struct input_handle *handle) 853 { 854 struct evdev *evdev = handle->private; 855 856 device_del(&evdev->dev); 857 evdev_cleanup(evdev); 858 input_unregister_handle(handle); 859 put_device(&evdev->dev); 860 } 861 862 static const struct input_device_id evdev_ids[] = { 863 { .driver_info = 1 }, /* Matches all devices */ 864 { }, /* Terminating zero entry */ 865 }; 866 867 MODULE_DEVICE_TABLE(input, evdev_ids); 868 869 static struct input_handler evdev_handler = { 870 .event = evdev_event, 871 .connect = evdev_connect, 872 .disconnect = evdev_disconnect, 873 .fops = &evdev_fops, 874 .minor = EVDEV_MINOR_BASE, 875 .name = "evdev", 876 .id_table = evdev_ids, 877 }; 878 879 static int __init evdev_init(void) 880 { 881 return input_register_handler(&evdev_handler); 882 } 883 884 static void __exit evdev_exit(void) 885 { 886 input_unregister_handler(&evdev_handler); 887 } 888 889 module_init(evdev_init); 890 module_exit(evdev_exit); 891 892 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); 893 MODULE_DESCRIPTION("Input driver event char devices"); 894 MODULE_LICENSE("GPL"); 895