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 if (event->type == EV_SYN) 63 kill_fasync(&client->fasync, SIGIO, POLL_IN); 64 } 65 66 /* 67 * Pass incoming event to all connected clients. 68 */ 69 static void evdev_event(struct input_handle *handle, 70 unsigned int type, unsigned int code, int value) 71 { 72 struct evdev *evdev = handle->private; 73 struct evdev_client *client; 74 struct input_event event; 75 76 do_gettimeofday(&event.time); 77 event.type = type; 78 event.code = code; 79 event.value = value; 80 81 rcu_read_lock(); 82 83 client = rcu_dereference(evdev->grab); 84 if (client) 85 evdev_pass_event(client, &event); 86 else 87 list_for_each_entry_rcu(client, &evdev->client_list, node) 88 evdev_pass_event(client, &event); 89 90 rcu_read_unlock(); 91 92 wake_up_interruptible(&evdev->wait); 93 } 94 95 static int evdev_fasync(int fd, struct file *file, int on) 96 { 97 struct evdev_client *client = file->private_data; 98 99 return fasync_helper(fd, file, on, &client->fasync); 100 } 101 102 static int evdev_flush(struct file *file, fl_owner_t id) 103 { 104 struct evdev_client *client = file->private_data; 105 struct evdev *evdev = client->evdev; 106 int retval; 107 108 retval = mutex_lock_interruptible(&evdev->mutex); 109 if (retval) 110 return retval; 111 112 if (!evdev->exist) 113 retval = -ENODEV; 114 else 115 retval = input_flush_device(&evdev->handle, file); 116 117 mutex_unlock(&evdev->mutex); 118 return retval; 119 } 120 121 static void evdev_free(struct device *dev) 122 { 123 struct evdev *evdev = container_of(dev, struct evdev, dev); 124 125 input_put_device(evdev->handle.dev); 126 kfree(evdev); 127 } 128 129 /* 130 * Grabs an event device (along with underlying input device). 131 * This function is called with evdev->mutex taken. 132 */ 133 static int evdev_grab(struct evdev *evdev, struct evdev_client *client) 134 { 135 int error; 136 137 if (evdev->grab) 138 return -EBUSY; 139 140 error = input_grab_device(&evdev->handle); 141 if (error) 142 return error; 143 144 rcu_assign_pointer(evdev->grab, client); 145 synchronize_rcu(); 146 147 return 0; 148 } 149 150 static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client) 151 { 152 if (evdev->grab != client) 153 return -EINVAL; 154 155 rcu_assign_pointer(evdev->grab, NULL); 156 synchronize_rcu(); 157 input_release_device(&evdev->handle); 158 159 return 0; 160 } 161 162 static void evdev_attach_client(struct evdev *evdev, 163 struct evdev_client *client) 164 { 165 spin_lock(&evdev->client_lock); 166 list_add_tail_rcu(&client->node, &evdev->client_list); 167 spin_unlock(&evdev->client_lock); 168 synchronize_rcu(); 169 } 170 171 static void evdev_detach_client(struct evdev *evdev, 172 struct evdev_client *client) 173 { 174 spin_lock(&evdev->client_lock); 175 list_del_rcu(&client->node); 176 spin_unlock(&evdev->client_lock); 177 synchronize_rcu(); 178 } 179 180 static int evdev_open_device(struct evdev *evdev) 181 { 182 int retval; 183 184 retval = mutex_lock_interruptible(&evdev->mutex); 185 if (retval) 186 return retval; 187 188 if (!evdev->exist) 189 retval = -ENODEV; 190 else if (!evdev->open++) { 191 retval = input_open_device(&evdev->handle); 192 if (retval) 193 evdev->open--; 194 } 195 196 mutex_unlock(&evdev->mutex); 197 return retval; 198 } 199 200 static void evdev_close_device(struct evdev *evdev) 201 { 202 mutex_lock(&evdev->mutex); 203 204 if (evdev->exist && !--evdev->open) 205 input_close_device(&evdev->handle); 206 207 mutex_unlock(&evdev->mutex); 208 } 209 210 /* 211 * Wake up users waiting for IO so they can disconnect from 212 * dead device. 213 */ 214 static void evdev_hangup(struct evdev *evdev) 215 { 216 struct evdev_client *client; 217 218 spin_lock(&evdev->client_lock); 219 list_for_each_entry(client, &evdev->client_list, node) 220 kill_fasync(&client->fasync, SIGIO, POLL_HUP); 221 spin_unlock(&evdev->client_lock); 222 223 wake_up_interruptible(&evdev->wait); 224 } 225 226 static int evdev_release(struct inode *inode, struct file *file) 227 { 228 struct evdev_client *client = file->private_data; 229 struct evdev *evdev = client->evdev; 230 231 mutex_lock(&evdev->mutex); 232 if (evdev->grab == client) 233 evdev_ungrab(evdev, client); 234 mutex_unlock(&evdev->mutex); 235 236 evdev_detach_client(evdev, client); 237 kfree(client); 238 239 evdev_close_device(evdev); 240 put_device(&evdev->dev); 241 242 return 0; 243 } 244 245 static int evdev_open(struct inode *inode, struct file *file) 246 { 247 struct evdev *evdev; 248 struct evdev_client *client; 249 int i = iminor(inode) - EVDEV_MINOR_BASE; 250 int error; 251 252 if (i >= EVDEV_MINORS) 253 return -ENODEV; 254 255 error = mutex_lock_interruptible(&evdev_table_mutex); 256 if (error) 257 return error; 258 evdev = evdev_table[i]; 259 if (evdev) 260 get_device(&evdev->dev); 261 mutex_unlock(&evdev_table_mutex); 262 263 if (!evdev) 264 return -ENODEV; 265 266 client = kzalloc(sizeof(struct evdev_client), GFP_KERNEL); 267 if (!client) { 268 error = -ENOMEM; 269 goto err_put_evdev; 270 } 271 272 spin_lock_init(&client->buffer_lock); 273 client->evdev = evdev; 274 evdev_attach_client(evdev, client); 275 276 error = evdev_open_device(evdev); 277 if (error) 278 goto err_free_client; 279 280 file->private_data = client; 281 return 0; 282 283 err_free_client: 284 evdev_detach_client(evdev, client); 285 kfree(client); 286 err_put_evdev: 287 put_device(&evdev->dev); 288 return error; 289 } 290 291 static ssize_t evdev_write(struct file *file, const char __user *buffer, 292 size_t count, loff_t *ppos) 293 { 294 struct evdev_client *client = file->private_data; 295 struct evdev *evdev = client->evdev; 296 struct input_event event; 297 int retval; 298 299 retval = mutex_lock_interruptible(&evdev->mutex); 300 if (retval) 301 return retval; 302 303 if (!evdev->exist) { 304 retval = -ENODEV; 305 goto out; 306 } 307 308 while (retval < count) { 309 310 if (input_event_from_user(buffer + retval, &event)) { 311 retval = -EFAULT; 312 goto out; 313 } 314 315 input_inject_event(&evdev->handle, 316 event.type, event.code, event.value); 317 retval += input_event_size(); 318 } 319 320 out: 321 mutex_unlock(&evdev->mutex); 322 return retval; 323 } 324 325 static int evdev_fetch_next_event(struct evdev_client *client, 326 struct input_event *event) 327 { 328 int have_event; 329 330 spin_lock_irq(&client->buffer_lock); 331 332 have_event = client->head != client->tail; 333 if (have_event) { 334 *event = client->buffer[client->tail++]; 335 client->tail &= EVDEV_BUFFER_SIZE - 1; 336 } 337 338 spin_unlock_irq(&client->buffer_lock); 339 340 return have_event; 341 } 342 343 static ssize_t evdev_read(struct file *file, char __user *buffer, 344 size_t count, loff_t *ppos) 345 { 346 struct evdev_client *client = file->private_data; 347 struct evdev *evdev = client->evdev; 348 struct input_event event; 349 int retval; 350 351 if (count < input_event_size()) 352 return -EINVAL; 353 354 if (client->head == client->tail && evdev->exist && 355 (file->f_flags & O_NONBLOCK)) 356 return -EAGAIN; 357 358 retval = wait_event_interruptible(evdev->wait, 359 client->head != client->tail || !evdev->exist); 360 if (retval) 361 return retval; 362 363 if (!evdev->exist) 364 return -ENODEV; 365 366 while (retval + input_event_size() <= count && 367 evdev_fetch_next_event(client, &event)) { 368 369 if (input_event_to_user(buffer + retval, &event)) 370 return -EFAULT; 371 372 retval += input_event_size(); 373 } 374 375 return retval; 376 } 377 378 /* No kernel lock - fine */ 379 static unsigned int evdev_poll(struct file *file, poll_table *wait) 380 { 381 struct evdev_client *client = file->private_data; 382 struct evdev *evdev = client->evdev; 383 384 poll_wait(file, &evdev->wait, wait); 385 return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) | 386 (evdev->exist ? 0 : (POLLHUP | POLLERR)); 387 } 388 389 #ifdef CONFIG_COMPAT 390 391 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8) 392 #define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1) 393 394 #ifdef __BIG_ENDIAN 395 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 396 unsigned int maxlen, void __user *p, int compat) 397 { 398 int len, i; 399 400 if (compat) { 401 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t); 402 if (len > maxlen) 403 len = maxlen; 404 405 for (i = 0; i < len / sizeof(compat_long_t); i++) 406 if (copy_to_user((compat_long_t __user *) p + i, 407 (compat_long_t *) bits + 408 i + 1 - ((i % 2) << 1), 409 sizeof(compat_long_t))) 410 return -EFAULT; 411 } else { 412 len = BITS_TO_LONGS(maxbit) * sizeof(long); 413 if (len > maxlen) 414 len = maxlen; 415 416 if (copy_to_user(p, bits, len)) 417 return -EFAULT; 418 } 419 420 return len; 421 } 422 #else 423 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 424 unsigned int maxlen, void __user *p, int compat) 425 { 426 int len = compat ? 427 BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) : 428 BITS_TO_LONGS(maxbit) * sizeof(long); 429 430 if (len > maxlen) 431 len = maxlen; 432 433 return copy_to_user(p, bits, len) ? -EFAULT : len; 434 } 435 #endif /* __BIG_ENDIAN */ 436 437 #else 438 439 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 440 unsigned int maxlen, void __user *p, int compat) 441 { 442 int len = BITS_TO_LONGS(maxbit) * sizeof(long); 443 444 if (len > maxlen) 445 len = maxlen; 446 447 return copy_to_user(p, bits, len) ? -EFAULT : len; 448 } 449 450 #endif /* CONFIG_COMPAT */ 451 452 static int str_to_user(const char *str, unsigned int maxlen, void __user *p) 453 { 454 int len; 455 456 if (!str) 457 return -ENOENT; 458 459 len = strlen(str) + 1; 460 if (len > maxlen) 461 len = maxlen; 462 463 return copy_to_user(p, str, len) ? -EFAULT : len; 464 } 465 466 #define OLD_KEY_MAX 0x1ff 467 static int handle_eviocgbit(struct input_dev *dev, unsigned int cmd, void __user *p, int compat_mode) 468 { 469 static unsigned long keymax_warn_time; 470 unsigned long *bits; 471 int len; 472 473 switch (_IOC_NR(cmd) & EV_MAX) { 474 475 case 0: bits = dev->evbit; len = EV_MAX; break; 476 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break; 477 case EV_REL: bits = dev->relbit; len = REL_MAX; break; 478 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break; 479 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break; 480 case EV_LED: bits = dev->ledbit; len = LED_MAX; break; 481 case EV_SND: bits = dev->sndbit; len = SND_MAX; break; 482 case EV_FF: bits = dev->ffbit; len = FF_MAX; break; 483 case EV_SW: bits = dev->swbit; len = SW_MAX; break; 484 default: return -EINVAL; 485 } 486 487 /* 488 * Work around bugs in userspace programs that like to do 489 * EVIOCGBIT(EV_KEY, KEY_MAX) and not realize that 'len' 490 * should be in bytes, not in bits. 491 */ 492 if ((_IOC_NR(cmd) & EV_MAX) == EV_KEY && _IOC_SIZE(cmd) == OLD_KEY_MAX) { 493 len = OLD_KEY_MAX; 494 if (printk_timed_ratelimit(&keymax_warn_time, 10 * 1000)) 495 printk(KERN_WARNING 496 "evdev.c(EVIOCGBIT): Suspicious buffer size %u, " 497 "limiting output to %zu bytes. See " 498 "http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n", 499 OLD_KEY_MAX, 500 BITS_TO_LONGS(OLD_KEY_MAX) * sizeof(long)); 501 } 502 503 return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode); 504 } 505 #undef OLD_KEY_MAX 506 507 static long evdev_do_ioctl(struct file *file, unsigned int cmd, 508 void __user *p, int compat_mode) 509 { 510 struct evdev_client *client = file->private_data; 511 struct evdev *evdev = client->evdev; 512 struct input_dev *dev = evdev->handle.dev; 513 struct input_absinfo abs; 514 struct ff_effect effect; 515 int __user *ip = (int __user *)p; 516 int i, t, u, v; 517 int error; 518 519 switch (cmd) { 520 521 case EVIOCGVERSION: 522 return put_user(EV_VERSION, ip); 523 524 case EVIOCGID: 525 if (copy_to_user(p, &dev->id, sizeof(struct input_id))) 526 return -EFAULT; 527 return 0; 528 529 case EVIOCGREP: 530 if (!test_bit(EV_REP, dev->evbit)) 531 return -ENOSYS; 532 if (put_user(dev->rep[REP_DELAY], ip)) 533 return -EFAULT; 534 if (put_user(dev->rep[REP_PERIOD], ip + 1)) 535 return -EFAULT; 536 return 0; 537 538 case EVIOCSREP: 539 if (!test_bit(EV_REP, dev->evbit)) 540 return -ENOSYS; 541 if (get_user(u, ip)) 542 return -EFAULT; 543 if (get_user(v, ip + 1)) 544 return -EFAULT; 545 546 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u); 547 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v); 548 549 return 0; 550 551 case EVIOCGKEYCODE: 552 if (get_user(t, ip)) 553 return -EFAULT; 554 555 error = input_get_keycode(dev, t, &v); 556 if (error) 557 return error; 558 559 if (put_user(v, ip + 1)) 560 return -EFAULT; 561 562 return 0; 563 564 case EVIOCSKEYCODE: 565 if (get_user(t, ip) || get_user(v, ip + 1)) 566 return -EFAULT; 567 568 return input_set_keycode(dev, t, v); 569 570 case EVIOCRMFF: 571 return input_ff_erase(dev, (int)(unsigned long) p, file); 572 573 case EVIOCGEFFECTS: 574 i = test_bit(EV_FF, dev->evbit) ? 575 dev->ff->max_effects : 0; 576 if (put_user(i, ip)) 577 return -EFAULT; 578 return 0; 579 580 case EVIOCGRAB: 581 if (p) 582 return evdev_grab(evdev, client); 583 else 584 return evdev_ungrab(evdev, client); 585 586 default: 587 588 if (_IOC_TYPE(cmd) != 'E') 589 return -EINVAL; 590 591 if (_IOC_DIR(cmd) == _IOC_READ) { 592 593 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0))) 594 return handle_eviocgbit(dev, cmd, p, compat_mode); 595 596 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0))) 597 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd), 598 p, compat_mode); 599 600 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0))) 601 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd), 602 p, compat_mode); 603 604 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0))) 605 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd), 606 p, compat_mode); 607 608 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0))) 609 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd), 610 p, compat_mode); 611 612 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) 613 return str_to_user(dev->name, _IOC_SIZE(cmd), p); 614 615 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) 616 return str_to_user(dev->phys, _IOC_SIZE(cmd), p); 617 618 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) 619 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p); 620 621 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) { 622 623 t = _IOC_NR(cmd) & ABS_MAX; 624 625 abs.value = dev->abs[t]; 626 abs.minimum = dev->absmin[t]; 627 abs.maximum = dev->absmax[t]; 628 abs.fuzz = dev->absfuzz[t]; 629 abs.flat = dev->absflat[t]; 630 abs.resolution = dev->absres[t]; 631 632 if (copy_to_user(p, &abs, min_t(size_t, 633 _IOC_SIZE(cmd), 634 sizeof(struct input_absinfo)))) 635 return -EFAULT; 636 637 return 0; 638 } 639 640 } 641 642 if (_IOC_DIR(cmd) == _IOC_WRITE) { 643 644 if (_IOC_NR(cmd) == _IOC_NR(EVIOCSFF)) { 645 646 if (input_ff_effect_from_user(p, _IOC_SIZE(cmd), &effect)) 647 return -EFAULT; 648 649 error = input_ff_upload(dev, &effect, file); 650 651 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id))) 652 return -EFAULT; 653 654 return error; 655 } 656 657 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) { 658 659 t = _IOC_NR(cmd) & ABS_MAX; 660 661 if (copy_from_user(&abs, p, min_t(size_t, 662 _IOC_SIZE(cmd), 663 sizeof(struct input_absinfo)))) 664 return -EFAULT; 665 666 /* 667 * Take event lock to ensure that we are not 668 * changing device parameters in the middle 669 * of event. 670 */ 671 spin_lock_irq(&dev->event_lock); 672 673 dev->abs[t] = abs.value; 674 dev->absmin[t] = abs.minimum; 675 dev->absmax[t] = abs.maximum; 676 dev->absfuzz[t] = abs.fuzz; 677 dev->absflat[t] = abs.flat; 678 dev->absres[t] = _IOC_SIZE(cmd) < sizeof(struct input_absinfo) ? 679 0 : abs.resolution; 680 681 spin_unlock_irq(&dev->event_lock); 682 683 return 0; 684 } 685 } 686 } 687 return -EINVAL; 688 } 689 690 static long evdev_ioctl_handler(struct file *file, unsigned int cmd, 691 void __user *p, int compat_mode) 692 { 693 struct evdev_client *client = file->private_data; 694 struct evdev *evdev = client->evdev; 695 int retval; 696 697 retval = mutex_lock_interruptible(&evdev->mutex); 698 if (retval) 699 return retval; 700 701 if (!evdev->exist) { 702 retval = -ENODEV; 703 goto out; 704 } 705 706 retval = evdev_do_ioctl(file, cmd, p, compat_mode); 707 708 out: 709 mutex_unlock(&evdev->mutex); 710 return retval; 711 } 712 713 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 714 { 715 return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0); 716 } 717 718 #ifdef CONFIG_COMPAT 719 static long evdev_ioctl_compat(struct file *file, 720 unsigned int cmd, unsigned long arg) 721 { 722 return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1); 723 } 724 #endif 725 726 static const struct file_operations evdev_fops = { 727 .owner = THIS_MODULE, 728 .read = evdev_read, 729 .write = evdev_write, 730 .poll = evdev_poll, 731 .open = evdev_open, 732 .release = evdev_release, 733 .unlocked_ioctl = evdev_ioctl, 734 #ifdef CONFIG_COMPAT 735 .compat_ioctl = evdev_ioctl_compat, 736 #endif 737 .fasync = evdev_fasync, 738 .flush = evdev_flush 739 }; 740 741 static int evdev_install_chrdev(struct evdev *evdev) 742 { 743 /* 744 * No need to do any locking here as calls to connect and 745 * disconnect are serialized by the input core 746 */ 747 evdev_table[evdev->minor] = evdev; 748 return 0; 749 } 750 751 static void evdev_remove_chrdev(struct evdev *evdev) 752 { 753 /* 754 * Lock evdev table to prevent race with evdev_open() 755 */ 756 mutex_lock(&evdev_table_mutex); 757 evdev_table[evdev->minor] = NULL; 758 mutex_unlock(&evdev_table_mutex); 759 } 760 761 /* 762 * Mark device non-existent. This disables writes, ioctls and 763 * prevents new users from opening the device. Already posted 764 * blocking reads will stay, however new ones will fail. 765 */ 766 static void evdev_mark_dead(struct evdev *evdev) 767 { 768 mutex_lock(&evdev->mutex); 769 evdev->exist = 0; 770 mutex_unlock(&evdev->mutex); 771 } 772 773 static void evdev_cleanup(struct evdev *evdev) 774 { 775 struct input_handle *handle = &evdev->handle; 776 777 evdev_mark_dead(evdev); 778 evdev_hangup(evdev); 779 evdev_remove_chrdev(evdev); 780 781 /* evdev is marked dead so no one else accesses evdev->open */ 782 if (evdev->open) { 783 input_flush_device(handle, NULL); 784 input_close_device(handle); 785 } 786 } 787 788 /* 789 * Create new evdev device. Note that input core serializes calls 790 * to connect and disconnect so we don't need to lock evdev_table here. 791 */ 792 static int evdev_connect(struct input_handler *handler, struct input_dev *dev, 793 const struct input_device_id *id) 794 { 795 struct evdev *evdev; 796 int minor; 797 int error; 798 799 for (minor = 0; minor < EVDEV_MINORS; minor++) 800 if (!evdev_table[minor]) 801 break; 802 803 if (minor == EVDEV_MINORS) { 804 printk(KERN_ERR "evdev: no more free evdev devices\n"); 805 return -ENFILE; 806 } 807 808 evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL); 809 if (!evdev) 810 return -ENOMEM; 811 812 INIT_LIST_HEAD(&evdev->client_list); 813 spin_lock_init(&evdev->client_lock); 814 mutex_init(&evdev->mutex); 815 init_waitqueue_head(&evdev->wait); 816 817 dev_set_name(&evdev->dev, "event%d", minor); 818 evdev->exist = 1; 819 evdev->minor = minor; 820 821 evdev->handle.dev = input_get_device(dev); 822 evdev->handle.name = dev_name(&evdev->dev); 823 evdev->handle.handler = handler; 824 evdev->handle.private = evdev; 825 826 evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor); 827 evdev->dev.class = &input_class; 828 evdev->dev.parent = &dev->dev; 829 evdev->dev.release = evdev_free; 830 device_initialize(&evdev->dev); 831 832 error = input_register_handle(&evdev->handle); 833 if (error) 834 goto err_free_evdev; 835 836 error = evdev_install_chrdev(evdev); 837 if (error) 838 goto err_unregister_handle; 839 840 error = device_add(&evdev->dev); 841 if (error) 842 goto err_cleanup_evdev; 843 844 return 0; 845 846 err_cleanup_evdev: 847 evdev_cleanup(evdev); 848 err_unregister_handle: 849 input_unregister_handle(&evdev->handle); 850 err_free_evdev: 851 put_device(&evdev->dev); 852 return error; 853 } 854 855 static void evdev_disconnect(struct input_handle *handle) 856 { 857 struct evdev *evdev = handle->private; 858 859 device_del(&evdev->dev); 860 evdev_cleanup(evdev); 861 input_unregister_handle(handle); 862 put_device(&evdev->dev); 863 } 864 865 static const struct input_device_id evdev_ids[] = { 866 { .driver_info = 1 }, /* Matches all devices */ 867 { }, /* Terminating zero entry */ 868 }; 869 870 MODULE_DEVICE_TABLE(input, evdev_ids); 871 872 static struct input_handler evdev_handler = { 873 .event = evdev_event, 874 .connect = evdev_connect, 875 .disconnect = evdev_disconnect, 876 .fops = &evdev_fops, 877 .minor = EVDEV_MINOR_BASE, 878 .name = "evdev", 879 .id_table = evdev_ids, 880 }; 881 882 static int __init evdev_init(void) 883 { 884 return input_register_handler(&evdev_handler); 885 } 886 887 static void __exit evdev_exit(void) 888 { 889 input_unregister_handler(&evdev_handler); 890 } 891 892 module_init(evdev_init); 893 module_exit(evdev_exit); 894 895 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); 896 MODULE_DESCRIPTION("Input driver event char devices"); 897 MODULE_LICENSE("GPL"); 898