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/sched.h> 17 #include <linux/slab.h> 18 #include <linux/module.h> 19 #include <linux/init.h> 20 #include <linux/input.h> 21 #include <linux/major.h> 22 #include <linux/device.h> 23 #include "input-compat.h" 24 25 struct evdev { 26 int exist; 27 int open; 28 int minor; 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 98 return fasync_helper(fd, file, on, &client->fasync); 99 } 100 101 static int evdev_flush(struct file *file, fl_owner_t id) 102 { 103 struct evdev_client *client = file->private_data; 104 struct evdev *evdev = client->evdev; 105 int retval; 106 107 retval = mutex_lock_interruptible(&evdev->mutex); 108 if (retval) 109 return retval; 110 111 if (!evdev->exist) 112 retval = -ENODEV; 113 else 114 retval = input_flush_device(&evdev->handle, file); 115 116 mutex_unlock(&evdev->mutex); 117 return retval; 118 } 119 120 static void evdev_free(struct device *dev) 121 { 122 struct evdev *evdev = container_of(dev, struct evdev, dev); 123 124 input_put_device(evdev->handle.dev); 125 kfree(evdev); 126 } 127 128 /* 129 * Grabs an event device (along with underlying input device). 130 * This function is called with evdev->mutex taken. 131 */ 132 static int evdev_grab(struct evdev *evdev, struct evdev_client *client) 133 { 134 int error; 135 136 if (evdev->grab) 137 return -EBUSY; 138 139 error = input_grab_device(&evdev->handle); 140 if (error) 141 return error; 142 143 rcu_assign_pointer(evdev->grab, client); 144 synchronize_rcu(); 145 146 return 0; 147 } 148 149 static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client) 150 { 151 if (evdev->grab != client) 152 return -EINVAL; 153 154 rcu_assign_pointer(evdev->grab, NULL); 155 synchronize_rcu(); 156 input_release_device(&evdev->handle); 157 158 return 0; 159 } 160 161 static void evdev_attach_client(struct evdev *evdev, 162 struct evdev_client *client) 163 { 164 spin_lock(&evdev->client_lock); 165 list_add_tail_rcu(&client->node, &evdev->client_list); 166 spin_unlock(&evdev->client_lock); 167 synchronize_rcu(); 168 } 169 170 static void evdev_detach_client(struct evdev *evdev, 171 struct evdev_client *client) 172 { 173 spin_lock(&evdev->client_lock); 174 list_del_rcu(&client->node); 175 spin_unlock(&evdev->client_lock); 176 synchronize_rcu(); 177 } 178 179 static int evdev_open_device(struct evdev *evdev) 180 { 181 int retval; 182 183 retval = mutex_lock_interruptible(&evdev->mutex); 184 if (retval) 185 return retval; 186 187 if (!evdev->exist) 188 retval = -ENODEV; 189 else if (!evdev->open++) { 190 retval = input_open_device(&evdev->handle); 191 if (retval) 192 evdev->open--; 193 } 194 195 mutex_unlock(&evdev->mutex); 196 return retval; 197 } 198 199 static void evdev_close_device(struct evdev *evdev) 200 { 201 mutex_lock(&evdev->mutex); 202 203 if (evdev->exist && !--evdev->open) 204 input_close_device(&evdev->handle); 205 206 mutex_unlock(&evdev->mutex); 207 } 208 209 /* 210 * Wake up users waiting for IO so they can disconnect from 211 * dead device. 212 */ 213 static void evdev_hangup(struct evdev *evdev) 214 { 215 struct evdev_client *client; 216 217 spin_lock(&evdev->client_lock); 218 list_for_each_entry(client, &evdev->client_list, node) 219 kill_fasync(&client->fasync, SIGIO, POLL_HUP); 220 spin_unlock(&evdev->client_lock); 221 222 wake_up_interruptible(&evdev->wait); 223 } 224 225 static int evdev_release(struct inode *inode, struct file *file) 226 { 227 struct evdev_client *client = file->private_data; 228 struct evdev *evdev = client->evdev; 229 230 mutex_lock(&evdev->mutex); 231 if (evdev->grab == client) 232 evdev_ungrab(evdev, client); 233 mutex_unlock(&evdev->mutex); 234 235 evdev_detach_client(evdev, client); 236 kfree(client); 237 238 evdev_close_device(evdev); 239 put_device(&evdev->dev); 240 241 return 0; 242 } 243 244 static int evdev_open(struct inode *inode, struct file *file) 245 { 246 struct evdev *evdev; 247 struct evdev_client *client; 248 int i = iminor(inode) - EVDEV_MINOR_BASE; 249 int error; 250 251 if (i >= EVDEV_MINORS) 252 return -ENODEV; 253 254 error = mutex_lock_interruptible(&evdev_table_mutex); 255 if (error) 256 return error; 257 evdev = evdev_table[i]; 258 if (evdev) 259 get_device(&evdev->dev); 260 mutex_unlock(&evdev_table_mutex); 261 262 if (!evdev) 263 return -ENODEV; 264 265 client = kzalloc(sizeof(struct evdev_client), GFP_KERNEL); 266 if (!client) { 267 error = -ENOMEM; 268 goto err_put_evdev; 269 } 270 271 spin_lock_init(&client->buffer_lock); 272 client->evdev = evdev; 273 evdev_attach_client(evdev, client); 274 275 error = evdev_open_device(evdev); 276 if (error) 277 goto err_free_client; 278 279 file->private_data = client; 280 return 0; 281 282 err_free_client: 283 evdev_detach_client(evdev, client); 284 kfree(client); 285 err_put_evdev: 286 put_device(&evdev->dev); 287 return error; 288 } 289 290 static ssize_t evdev_write(struct file *file, const char __user *buffer, 291 size_t count, loff_t *ppos) 292 { 293 struct evdev_client *client = file->private_data; 294 struct evdev *evdev = client->evdev; 295 struct input_event event; 296 int retval; 297 298 retval = mutex_lock_interruptible(&evdev->mutex); 299 if (retval) 300 return retval; 301 302 if (!evdev->exist) { 303 retval = -ENODEV; 304 goto out; 305 } 306 307 while (retval < count) { 308 309 if (input_event_from_user(buffer + retval, &event)) { 310 retval = -EFAULT; 311 goto out; 312 } 313 314 input_inject_event(&evdev->handle, 315 event.type, event.code, event.value); 316 retval += input_event_size(); 317 } 318 319 out: 320 mutex_unlock(&evdev->mutex); 321 return retval; 322 } 323 324 static int evdev_fetch_next_event(struct evdev_client *client, 325 struct input_event *event) 326 { 327 int have_event; 328 329 spin_lock_irq(&client->buffer_lock); 330 331 have_event = client->head != client->tail; 332 if (have_event) { 333 *event = client->buffer[client->tail++]; 334 client->tail &= EVDEV_BUFFER_SIZE - 1; 335 } 336 337 spin_unlock_irq(&client->buffer_lock); 338 339 return have_event; 340 } 341 342 static ssize_t evdev_read(struct file *file, char __user *buffer, 343 size_t count, loff_t *ppos) 344 { 345 struct evdev_client *client = file->private_data; 346 struct evdev *evdev = client->evdev; 347 struct input_event event; 348 int retval; 349 350 if (count < input_event_size()) 351 return -EINVAL; 352 353 if (client->head == client->tail && evdev->exist && 354 (file->f_flags & O_NONBLOCK)) 355 return -EAGAIN; 356 357 retval = wait_event_interruptible(evdev->wait, 358 client->head != client->tail || !evdev->exist); 359 if (retval) 360 return retval; 361 362 if (!evdev->exist) 363 return -ENODEV; 364 365 while (retval + input_event_size() <= count && 366 evdev_fetch_next_event(client, &event)) { 367 368 if (input_event_to_user(buffer + retval, &event)) 369 return -EFAULT; 370 371 retval += input_event_size(); 372 } 373 374 return retval; 375 } 376 377 /* No kernel lock - fine */ 378 static unsigned int evdev_poll(struct file *file, poll_table *wait) 379 { 380 struct evdev_client *client = file->private_data; 381 struct evdev *evdev = client->evdev; 382 383 poll_wait(file, &evdev->wait, wait); 384 return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) | 385 (evdev->exist ? 0 : (POLLHUP | POLLERR)); 386 } 387 388 #ifdef CONFIG_COMPAT 389 390 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8) 391 #define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1) 392 393 #ifdef __BIG_ENDIAN 394 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 395 unsigned int maxlen, void __user *p, int compat) 396 { 397 int len, i; 398 399 if (compat) { 400 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t); 401 if (len > maxlen) 402 len = maxlen; 403 404 for (i = 0; i < len / sizeof(compat_long_t); i++) 405 if (copy_to_user((compat_long_t __user *) p + i, 406 (compat_long_t *) bits + 407 i + 1 - ((i % 2) << 1), 408 sizeof(compat_long_t))) 409 return -EFAULT; 410 } else { 411 len = BITS_TO_LONGS(maxbit) * sizeof(long); 412 if (len > maxlen) 413 len = maxlen; 414 415 if (copy_to_user(p, bits, len)) 416 return -EFAULT; 417 } 418 419 return len; 420 } 421 #else 422 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 423 unsigned int maxlen, void __user *p, int compat) 424 { 425 int len = compat ? 426 BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) : 427 BITS_TO_LONGS(maxbit) * sizeof(long); 428 429 if (len > maxlen) 430 len = maxlen; 431 432 return copy_to_user(p, bits, len) ? -EFAULT : len; 433 } 434 #endif /* __BIG_ENDIAN */ 435 436 #else 437 438 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 439 unsigned int maxlen, void __user *p, int compat) 440 { 441 int len = BITS_TO_LONGS(maxbit) * sizeof(long); 442 443 if (len > maxlen) 444 len = maxlen; 445 446 return copy_to_user(p, bits, len) ? -EFAULT : len; 447 } 448 449 #endif /* CONFIG_COMPAT */ 450 451 static int str_to_user(const char *str, unsigned int maxlen, void __user *p) 452 { 453 int len; 454 455 if (!str) 456 return -ENOENT; 457 458 len = strlen(str) + 1; 459 if (len > maxlen) 460 len = maxlen; 461 462 return copy_to_user(p, str, len) ? -EFAULT : len; 463 } 464 465 #define OLD_KEY_MAX 0x1ff 466 static int handle_eviocgbit(struct input_dev *dev, unsigned int cmd, void __user *p, int compat_mode) 467 { 468 static unsigned long keymax_warn_time; 469 unsigned long *bits; 470 int len; 471 472 switch (_IOC_NR(cmd) & EV_MAX) { 473 474 case 0: bits = dev->evbit; len = EV_MAX; break; 475 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break; 476 case EV_REL: bits = dev->relbit; len = REL_MAX; break; 477 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break; 478 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break; 479 case EV_LED: bits = dev->ledbit; len = LED_MAX; break; 480 case EV_SND: bits = dev->sndbit; len = SND_MAX; break; 481 case EV_FF: bits = dev->ffbit; len = FF_MAX; break; 482 case EV_SW: bits = dev->swbit; len = SW_MAX; break; 483 default: return -EINVAL; 484 } 485 486 /* 487 * Work around bugs in userspace programs that like to do 488 * EVIOCGBIT(EV_KEY, KEY_MAX) and not realize that 'len' 489 * should be in bytes, not in bits. 490 */ 491 if ((_IOC_NR(cmd) & EV_MAX) == EV_KEY && _IOC_SIZE(cmd) == OLD_KEY_MAX) { 492 len = OLD_KEY_MAX; 493 if (printk_timed_ratelimit(&keymax_warn_time, 10 * 1000)) 494 printk(KERN_WARNING 495 "evdev.c(EVIOCGBIT): Suspicious buffer size %u, " 496 "limiting output to %zu bytes. See " 497 "http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n", 498 OLD_KEY_MAX, 499 BITS_TO_LONGS(OLD_KEY_MAX) * sizeof(long)); 500 } 501 502 return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode); 503 } 504 #undef OLD_KEY_MAX 505 506 static long evdev_do_ioctl(struct file *file, unsigned int cmd, 507 void __user *p, int compat_mode) 508 { 509 struct evdev_client *client = file->private_data; 510 struct evdev *evdev = client->evdev; 511 struct input_dev *dev = evdev->handle.dev; 512 struct input_absinfo abs; 513 struct ff_effect effect; 514 int __user *ip = (int __user *)p; 515 int i, t, u, v; 516 int error; 517 518 switch (cmd) { 519 520 case EVIOCGVERSION: 521 return put_user(EV_VERSION, ip); 522 523 case EVIOCGID: 524 if (copy_to_user(p, &dev->id, sizeof(struct input_id))) 525 return -EFAULT; 526 return 0; 527 528 case EVIOCGREP: 529 if (!test_bit(EV_REP, dev->evbit)) 530 return -ENOSYS; 531 if (put_user(dev->rep[REP_DELAY], ip)) 532 return -EFAULT; 533 if (put_user(dev->rep[REP_PERIOD], ip + 1)) 534 return -EFAULT; 535 return 0; 536 537 case EVIOCSREP: 538 if (!test_bit(EV_REP, dev->evbit)) 539 return -ENOSYS; 540 if (get_user(u, ip)) 541 return -EFAULT; 542 if (get_user(v, ip + 1)) 543 return -EFAULT; 544 545 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u); 546 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v); 547 548 return 0; 549 550 case EVIOCGKEYCODE: 551 if (get_user(t, ip)) 552 return -EFAULT; 553 554 error = input_get_keycode(dev, t, &v); 555 if (error) 556 return error; 557 558 if (put_user(v, ip + 1)) 559 return -EFAULT; 560 561 return 0; 562 563 case EVIOCSKEYCODE: 564 if (get_user(t, ip) || get_user(v, ip + 1)) 565 return -EFAULT; 566 567 return input_set_keycode(dev, t, v); 568 569 case EVIOCRMFF: 570 return input_ff_erase(dev, (int)(unsigned long) p, file); 571 572 case EVIOCGEFFECTS: 573 i = test_bit(EV_FF, dev->evbit) ? 574 dev->ff->max_effects : 0; 575 if (put_user(i, ip)) 576 return -EFAULT; 577 return 0; 578 579 case EVIOCGRAB: 580 if (p) 581 return evdev_grab(evdev, client); 582 else 583 return evdev_ungrab(evdev, client); 584 585 default: 586 587 if (_IOC_TYPE(cmd) != 'E') 588 return -EINVAL; 589 590 if (_IOC_DIR(cmd) == _IOC_READ) { 591 592 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0))) 593 return handle_eviocgbit(dev, cmd, p, compat_mode); 594 595 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0))) 596 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd), 597 p, compat_mode); 598 599 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0))) 600 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd), 601 p, compat_mode); 602 603 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0))) 604 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd), 605 p, compat_mode); 606 607 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0))) 608 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd), 609 p, compat_mode); 610 611 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) 612 return str_to_user(dev->name, _IOC_SIZE(cmd), p); 613 614 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) 615 return str_to_user(dev->phys, _IOC_SIZE(cmd), p); 616 617 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) 618 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p); 619 620 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) { 621 622 t = _IOC_NR(cmd) & ABS_MAX; 623 624 abs.value = dev->abs[t]; 625 abs.minimum = dev->absmin[t]; 626 abs.maximum = dev->absmax[t]; 627 abs.fuzz = dev->absfuzz[t]; 628 abs.flat = dev->absflat[t]; 629 abs.resolution = dev->absres[t]; 630 631 if (copy_to_user(p, &abs, min_t(size_t, 632 _IOC_SIZE(cmd), 633 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, min_t(size_t, 661 _IOC_SIZE(cmd), 662 sizeof(struct input_absinfo)))) 663 return -EFAULT; 664 665 /* 666 * Take event lock to ensure that we are not 667 * changing device parameters in the middle 668 * of event. 669 */ 670 spin_lock_irq(&dev->event_lock); 671 672 dev->abs[t] = abs.value; 673 dev->absmin[t] = abs.minimum; 674 dev->absmax[t] = abs.maximum; 675 dev->absfuzz[t] = abs.fuzz; 676 dev->absflat[t] = abs.flat; 677 dev->absres[t] = _IOC_SIZE(cmd) < sizeof(struct input_absinfo) ? 678 0 : abs.resolution; 679 680 spin_unlock_irq(&dev->event_lock); 681 682 return 0; 683 } 684 } 685 } 686 return -EINVAL; 687 } 688 689 static long evdev_ioctl_handler(struct file *file, unsigned int cmd, 690 void __user *p, int compat_mode) 691 { 692 struct evdev_client *client = file->private_data; 693 struct evdev *evdev = client->evdev; 694 int retval; 695 696 retval = mutex_lock_interruptible(&evdev->mutex); 697 if (retval) 698 return retval; 699 700 if (!evdev->exist) { 701 retval = -ENODEV; 702 goto out; 703 } 704 705 retval = evdev_do_ioctl(file, cmd, p, compat_mode); 706 707 out: 708 mutex_unlock(&evdev->mutex); 709 return retval; 710 } 711 712 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 713 { 714 return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0); 715 } 716 717 #ifdef CONFIG_COMPAT 718 static long evdev_ioctl_compat(struct file *file, 719 unsigned int cmd, unsigned long arg) 720 { 721 return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1); 722 } 723 #endif 724 725 static const struct file_operations evdev_fops = { 726 .owner = THIS_MODULE, 727 .read = evdev_read, 728 .write = evdev_write, 729 .poll = evdev_poll, 730 .open = evdev_open, 731 .release = evdev_release, 732 .unlocked_ioctl = evdev_ioctl, 733 #ifdef CONFIG_COMPAT 734 .compat_ioctl = evdev_ioctl_compat, 735 #endif 736 .fasync = evdev_fasync, 737 .flush = evdev_flush 738 }; 739 740 static int evdev_install_chrdev(struct evdev *evdev) 741 { 742 /* 743 * No need to do any locking here as calls to connect and 744 * disconnect are serialized by the input core 745 */ 746 evdev_table[evdev->minor] = evdev; 747 return 0; 748 } 749 750 static void evdev_remove_chrdev(struct evdev *evdev) 751 { 752 /* 753 * Lock evdev table to prevent race with evdev_open() 754 */ 755 mutex_lock(&evdev_table_mutex); 756 evdev_table[evdev->minor] = NULL; 757 mutex_unlock(&evdev_table_mutex); 758 } 759 760 /* 761 * Mark device non-existent. This disables writes, ioctls and 762 * prevents new users from opening the device. Already posted 763 * blocking reads will stay, however new ones will fail. 764 */ 765 static void evdev_mark_dead(struct evdev *evdev) 766 { 767 mutex_lock(&evdev->mutex); 768 evdev->exist = 0; 769 mutex_unlock(&evdev->mutex); 770 } 771 772 static void evdev_cleanup(struct evdev *evdev) 773 { 774 struct input_handle *handle = &evdev->handle; 775 776 evdev_mark_dead(evdev); 777 evdev_hangup(evdev); 778 evdev_remove_chrdev(evdev); 779 780 /* evdev is marked dead so no one else accesses evdev->open */ 781 if (evdev->open) { 782 input_flush_device(handle, NULL); 783 input_close_device(handle); 784 } 785 } 786 787 /* 788 * Create new evdev device. Note that input core serializes calls 789 * to connect and disconnect so we don't need to lock evdev_table here. 790 */ 791 static int evdev_connect(struct input_handler *handler, struct input_dev *dev, 792 const struct input_device_id *id) 793 { 794 struct evdev *evdev; 795 int minor; 796 int error; 797 798 for (minor = 0; minor < EVDEV_MINORS; minor++) 799 if (!evdev_table[minor]) 800 break; 801 802 if (minor == EVDEV_MINORS) { 803 printk(KERN_ERR "evdev: no more free evdev devices\n"); 804 return -ENFILE; 805 } 806 807 evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL); 808 if (!evdev) 809 return -ENOMEM; 810 811 INIT_LIST_HEAD(&evdev->client_list); 812 spin_lock_init(&evdev->client_lock); 813 mutex_init(&evdev->mutex); 814 init_waitqueue_head(&evdev->wait); 815 816 dev_set_name(&evdev->dev, "event%d", minor); 817 evdev->exist = 1; 818 evdev->minor = minor; 819 820 evdev->handle.dev = input_get_device(dev); 821 evdev->handle.name = dev_name(&evdev->dev); 822 evdev->handle.handler = handler; 823 evdev->handle.private = evdev; 824 825 evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor); 826 evdev->dev.class = &input_class; 827 evdev->dev.parent = &dev->dev; 828 evdev->dev.release = evdev_free; 829 device_initialize(&evdev->dev); 830 831 error = input_register_handle(&evdev->handle); 832 if (error) 833 goto err_free_evdev; 834 835 error = evdev_install_chrdev(evdev); 836 if (error) 837 goto err_unregister_handle; 838 839 error = device_add(&evdev->dev); 840 if (error) 841 goto err_cleanup_evdev; 842 843 return 0; 844 845 err_cleanup_evdev: 846 evdev_cleanup(evdev); 847 err_unregister_handle: 848 input_unregister_handle(&evdev->handle); 849 err_free_evdev: 850 put_device(&evdev->dev); 851 return error; 852 } 853 854 static void evdev_disconnect(struct input_handle *handle) 855 { 856 struct evdev *evdev = handle->private; 857 858 device_del(&evdev->dev); 859 evdev_cleanup(evdev); 860 input_unregister_handle(handle); 861 put_device(&evdev->dev); 862 } 863 864 static const struct input_device_id evdev_ids[] = { 865 { .driver_info = 1 }, /* Matches all devices */ 866 { }, /* Terminating zero entry */ 867 }; 868 869 MODULE_DEVICE_TABLE(input, evdev_ids); 870 871 static struct input_handler evdev_handler = { 872 .event = evdev_event, 873 .connect = evdev_connect, 874 .disconnect = evdev_disconnect, 875 .fops = &evdev_fops, 876 .minor = EVDEV_MINOR_BASE, 877 .name = "evdev", 878 .id_table = evdev_ids, 879 }; 880 881 static int __init evdev_init(void) 882 { 883 return input_register_handler(&evdev_handler); 884 } 885 886 static void __exit evdev_exit(void) 887 { 888 input_unregister_handler(&evdev_handler); 889 } 890 891 module_init(evdev_init); 892 module_exit(evdev_exit); 893 894 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); 895 MODULE_DESCRIPTION("Input driver event char devices"); 896 MODULE_LICENSE("GPL"); 897