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 struct input_handle handle; 29 wait_queue_head_t wait; 30 struct evdev_client *grab; 31 struct list_head client_list; 32 spinlock_t client_lock; /* protects client_list */ 33 struct mutex mutex; 34 struct device dev; 35 }; 36 37 struct evdev_client { 38 struct input_event buffer[EVDEV_BUFFER_SIZE]; 39 int head; 40 int tail; 41 spinlock_t buffer_lock; /* protects access to buffer, head and tail */ 42 struct fasync_struct *fasync; 43 struct evdev *evdev; 44 struct list_head node; 45 }; 46 47 static struct evdev *evdev_table[EVDEV_MINORS]; 48 static DEFINE_MUTEX(evdev_table_mutex); 49 50 static void evdev_pass_event(struct evdev_client *client, 51 struct input_event *event) 52 { 53 /* 54 * Interrupts are disabled, just acquire the lock 55 */ 56 spin_lock(&client->buffer_lock); 57 client->buffer[client->head++] = *event; 58 client->head &= EVDEV_BUFFER_SIZE - 1; 59 spin_unlock(&client->buffer_lock); 60 61 kill_fasync(&client->fasync, SIGIO, POLL_IN); 62 } 63 64 /* 65 * Pass incoming event to all connected clients. 66 */ 67 static void evdev_event(struct input_handle *handle, 68 unsigned int type, unsigned int code, int value) 69 { 70 struct evdev *evdev = handle->private; 71 struct evdev_client *client; 72 struct input_event event; 73 74 do_gettimeofday(&event.time); 75 event.type = type; 76 event.code = code; 77 event.value = value; 78 79 rcu_read_lock(); 80 81 client = rcu_dereference(evdev->grab); 82 if (client) 83 evdev_pass_event(client, &event); 84 else 85 list_for_each_entry_rcu(client, &evdev->client_list, node) 86 evdev_pass_event(client, &event); 87 88 rcu_read_unlock(); 89 90 wake_up_interruptible(&evdev->wait); 91 } 92 93 static int evdev_fasync(int fd, struct file *file, int on) 94 { 95 struct evdev_client *client = file->private_data; 96 97 return fasync_helper(fd, file, on, &client->fasync); 98 } 99 100 static int evdev_flush(struct file *file, fl_owner_t id) 101 { 102 struct evdev_client *client = file->private_data; 103 struct evdev *evdev = client->evdev; 104 int retval; 105 106 retval = mutex_lock_interruptible(&evdev->mutex); 107 if (retval) 108 return retval; 109 110 if (!evdev->exist) 111 retval = -ENODEV; 112 else 113 retval = input_flush_device(&evdev->handle, file); 114 115 mutex_unlock(&evdev->mutex); 116 return retval; 117 } 118 119 static void evdev_free(struct device *dev) 120 { 121 struct evdev *evdev = container_of(dev, struct evdev, dev); 122 123 input_put_device(evdev->handle.dev); 124 kfree(evdev); 125 } 126 127 /* 128 * Grabs an event device (along with underlying input device). 129 * This function is called with evdev->mutex taken. 130 */ 131 static int evdev_grab(struct evdev *evdev, struct evdev_client *client) 132 { 133 int error; 134 135 if (evdev->grab) 136 return -EBUSY; 137 138 error = input_grab_device(&evdev->handle); 139 if (error) 140 return error; 141 142 rcu_assign_pointer(evdev->grab, client); 143 synchronize_rcu(); 144 145 return 0; 146 } 147 148 static int evdev_ungrab(struct evdev *evdev, struct evdev_client *client) 149 { 150 if (evdev->grab != client) 151 return -EINVAL; 152 153 rcu_assign_pointer(evdev->grab, NULL); 154 synchronize_rcu(); 155 input_release_device(&evdev->handle); 156 157 return 0; 158 } 159 160 static void evdev_attach_client(struct evdev *evdev, 161 struct evdev_client *client) 162 { 163 spin_lock(&evdev->client_lock); 164 list_add_tail_rcu(&client->node, &evdev->client_list); 165 spin_unlock(&evdev->client_lock); 166 synchronize_rcu(); 167 } 168 169 static void evdev_detach_client(struct evdev *evdev, 170 struct evdev_client *client) 171 { 172 spin_lock(&evdev->client_lock); 173 list_del_rcu(&client->node); 174 spin_unlock(&evdev->client_lock); 175 synchronize_rcu(); 176 } 177 178 static int evdev_open_device(struct evdev *evdev) 179 { 180 int retval; 181 182 retval = mutex_lock_interruptible(&evdev->mutex); 183 if (retval) 184 return retval; 185 186 if (!evdev->exist) 187 retval = -ENODEV; 188 else if (!evdev->open++) { 189 retval = input_open_device(&evdev->handle); 190 if (retval) 191 evdev->open--; 192 } 193 194 mutex_unlock(&evdev->mutex); 195 return retval; 196 } 197 198 static void evdev_close_device(struct evdev *evdev) 199 { 200 mutex_lock(&evdev->mutex); 201 202 if (evdev->exist && !--evdev->open) 203 input_close_device(&evdev->handle); 204 205 mutex_unlock(&evdev->mutex); 206 } 207 208 /* 209 * Wake up users waiting for IO so they can disconnect from 210 * dead device. 211 */ 212 static void evdev_hangup(struct evdev *evdev) 213 { 214 struct evdev_client *client; 215 216 spin_lock(&evdev->client_lock); 217 list_for_each_entry(client, &evdev->client_list, node) 218 kill_fasync(&client->fasync, SIGIO, POLL_HUP); 219 spin_unlock(&evdev->client_lock); 220 221 wake_up_interruptible(&evdev->wait); 222 } 223 224 static int evdev_release(struct inode *inode, struct file *file) 225 { 226 struct evdev_client *client = file->private_data; 227 struct evdev *evdev = client->evdev; 228 229 mutex_lock(&evdev->mutex); 230 if (evdev->grab == client) 231 evdev_ungrab(evdev, client); 232 mutex_unlock(&evdev->mutex); 233 234 evdev_detach_client(evdev, client); 235 kfree(client); 236 237 evdev_close_device(evdev); 238 put_device(&evdev->dev); 239 240 return 0; 241 } 242 243 static int evdev_open(struct inode *inode, struct file *file) 244 { 245 struct evdev *evdev; 246 struct evdev_client *client; 247 int i = iminor(inode) - EVDEV_MINOR_BASE; 248 int error; 249 250 if (i >= EVDEV_MINORS) 251 return -ENODEV; 252 253 error = mutex_lock_interruptible(&evdev_table_mutex); 254 if (error) 255 return error; 256 evdev = evdev_table[i]; 257 if (evdev) 258 get_device(&evdev->dev); 259 mutex_unlock(&evdev_table_mutex); 260 261 if (!evdev) 262 return -ENODEV; 263 264 client = kzalloc(sizeof(struct evdev_client), GFP_KERNEL); 265 if (!client) { 266 error = -ENOMEM; 267 goto err_put_evdev; 268 } 269 270 spin_lock_init(&client->buffer_lock); 271 client->evdev = evdev; 272 evdev_attach_client(evdev, client); 273 274 error = evdev_open_device(evdev); 275 if (error) 276 goto err_free_client; 277 278 file->private_data = client; 279 return 0; 280 281 err_free_client: 282 evdev_detach_client(evdev, client); 283 kfree(client); 284 err_put_evdev: 285 put_device(&evdev->dev); 286 return error; 287 } 288 289 static ssize_t evdev_write(struct file *file, const char __user *buffer, 290 size_t count, loff_t *ppos) 291 { 292 struct evdev_client *client = file->private_data; 293 struct evdev *evdev = client->evdev; 294 struct input_event event; 295 int retval; 296 297 retval = mutex_lock_interruptible(&evdev->mutex); 298 if (retval) 299 return retval; 300 301 if (!evdev->exist) { 302 retval = -ENODEV; 303 goto out; 304 } 305 306 while (retval < count) { 307 308 if (input_event_from_user(buffer + retval, &event)) { 309 retval = -EFAULT; 310 goto out; 311 } 312 313 input_inject_event(&evdev->handle, 314 event.type, event.code, event.value); 315 retval += input_event_size(); 316 } 317 318 out: 319 mutex_unlock(&evdev->mutex); 320 return retval; 321 } 322 323 static int evdev_fetch_next_event(struct evdev_client *client, 324 struct input_event *event) 325 { 326 int have_event; 327 328 spin_lock_irq(&client->buffer_lock); 329 330 have_event = client->head != client->tail; 331 if (have_event) { 332 *event = client->buffer[client->tail++]; 333 client->tail &= EVDEV_BUFFER_SIZE - 1; 334 } 335 336 spin_unlock_irq(&client->buffer_lock); 337 338 return have_event; 339 } 340 341 static ssize_t evdev_read(struct file *file, char __user *buffer, 342 size_t count, loff_t *ppos) 343 { 344 struct evdev_client *client = file->private_data; 345 struct evdev *evdev = client->evdev; 346 struct input_event event; 347 int retval; 348 349 if (count < input_event_size()) 350 return -EINVAL; 351 352 if (client->head == client->tail && evdev->exist && 353 (file->f_flags & O_NONBLOCK)) 354 return -EAGAIN; 355 356 retval = wait_event_interruptible(evdev->wait, 357 client->head != client->tail || !evdev->exist); 358 if (retval) 359 return retval; 360 361 if (!evdev->exist) 362 return -ENODEV; 363 364 while (retval + input_event_size() <= count && 365 evdev_fetch_next_event(client, &event)) { 366 367 if (input_event_to_user(buffer + retval, &event)) 368 return -EFAULT; 369 370 retval += input_event_size(); 371 } 372 373 return retval; 374 } 375 376 /* No kernel lock - fine */ 377 static unsigned int evdev_poll(struct file *file, poll_table *wait) 378 { 379 struct evdev_client *client = file->private_data; 380 struct evdev *evdev = client->evdev; 381 382 poll_wait(file, &evdev->wait, wait); 383 return ((client->head == client->tail) ? 0 : (POLLIN | POLLRDNORM)) | 384 (evdev->exist ? 0 : (POLLHUP | POLLERR)); 385 } 386 387 #ifdef CONFIG_COMPAT 388 389 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8) 390 #define BITS_TO_LONGS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1) 391 392 #ifdef __BIG_ENDIAN 393 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 394 unsigned int maxlen, void __user *p, int compat) 395 { 396 int len, i; 397 398 if (compat) { 399 len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t); 400 if (len > maxlen) 401 len = maxlen; 402 403 for (i = 0; i < len / sizeof(compat_long_t); i++) 404 if (copy_to_user((compat_long_t __user *) p + i, 405 (compat_long_t *) bits + 406 i + 1 - ((i % 2) << 1), 407 sizeof(compat_long_t))) 408 return -EFAULT; 409 } else { 410 len = BITS_TO_LONGS(maxbit) * sizeof(long); 411 if (len > maxlen) 412 len = maxlen; 413 414 if (copy_to_user(p, bits, len)) 415 return -EFAULT; 416 } 417 418 return len; 419 } 420 #else 421 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 422 unsigned int maxlen, void __user *p, int compat) 423 { 424 int len = compat ? 425 BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t) : 426 BITS_TO_LONGS(maxbit) * sizeof(long); 427 428 if (len > maxlen) 429 len = maxlen; 430 431 return copy_to_user(p, bits, len) ? -EFAULT : len; 432 } 433 #endif /* __BIG_ENDIAN */ 434 435 #else 436 437 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 438 unsigned int maxlen, void __user *p, int compat) 439 { 440 int len = BITS_TO_LONGS(maxbit) * sizeof(long); 441 442 if (len > maxlen) 443 len = maxlen; 444 445 return copy_to_user(p, bits, len) ? -EFAULT : len; 446 } 447 448 #endif /* CONFIG_COMPAT */ 449 450 static int str_to_user(const char *str, unsigned int maxlen, void __user *p) 451 { 452 int len; 453 454 if (!str) 455 return -ENOENT; 456 457 len = strlen(str) + 1; 458 if (len > maxlen) 459 len = maxlen; 460 461 return copy_to_user(p, str, len) ? -EFAULT : len; 462 } 463 464 #define OLD_KEY_MAX 0x1ff 465 static int handle_eviocgbit(struct input_dev *dev, unsigned int cmd, void __user *p, int compat_mode) 466 { 467 static unsigned long keymax_warn_time; 468 unsigned long *bits; 469 int len; 470 471 switch (_IOC_NR(cmd) & EV_MAX) { 472 473 case 0: bits = dev->evbit; len = EV_MAX; break; 474 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break; 475 case EV_REL: bits = dev->relbit; len = REL_MAX; break; 476 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break; 477 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break; 478 case EV_LED: bits = dev->ledbit; len = LED_MAX; break; 479 case EV_SND: bits = dev->sndbit; len = SND_MAX; break; 480 case EV_FF: bits = dev->ffbit; len = FF_MAX; break; 481 case EV_SW: bits = dev->swbit; len = SW_MAX; break; 482 default: return -EINVAL; 483 } 484 485 /* 486 * Work around bugs in userspace programs that like to do 487 * EVIOCGBIT(EV_KEY, KEY_MAX) and not realize that 'len' 488 * should be in bytes, not in bits. 489 */ 490 if ((_IOC_NR(cmd) & EV_MAX) == EV_KEY && _IOC_SIZE(cmd) == OLD_KEY_MAX) { 491 len = OLD_KEY_MAX; 492 if (printk_timed_ratelimit(&keymax_warn_time, 10 * 1000)) 493 printk(KERN_WARNING 494 "evdev.c(EVIOCGBIT): Suspicious buffer size %u, " 495 "limiting output to %zu bytes. See " 496 "http://userweb.kernel.org/~dtor/eviocgbit-bug.html\n", 497 OLD_KEY_MAX, 498 BITS_TO_LONGS(OLD_KEY_MAX) * sizeof(long)); 499 } 500 501 return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode); 502 } 503 #undef OLD_KEY_MAX 504 505 static long evdev_do_ioctl(struct file *file, unsigned int cmd, 506 void __user *p, int compat_mode) 507 { 508 struct evdev_client *client = file->private_data; 509 struct evdev *evdev = client->evdev; 510 struct input_dev *dev = evdev->handle.dev; 511 struct input_absinfo abs; 512 struct ff_effect effect; 513 int __user *ip = (int __user *)p; 514 int i, t, u, v; 515 int error; 516 517 switch (cmd) { 518 519 case EVIOCGVERSION: 520 return put_user(EV_VERSION, ip); 521 522 case EVIOCGID: 523 if (copy_to_user(p, &dev->id, sizeof(struct input_id))) 524 return -EFAULT; 525 return 0; 526 527 case EVIOCGREP: 528 if (!test_bit(EV_REP, dev->evbit)) 529 return -ENOSYS; 530 if (put_user(dev->rep[REP_DELAY], ip)) 531 return -EFAULT; 532 if (put_user(dev->rep[REP_PERIOD], ip + 1)) 533 return -EFAULT; 534 return 0; 535 536 case EVIOCSREP: 537 if (!test_bit(EV_REP, dev->evbit)) 538 return -ENOSYS; 539 if (get_user(u, ip)) 540 return -EFAULT; 541 if (get_user(v, ip + 1)) 542 return -EFAULT; 543 544 input_inject_event(&evdev->handle, EV_REP, REP_DELAY, u); 545 input_inject_event(&evdev->handle, EV_REP, REP_PERIOD, v); 546 547 return 0; 548 549 case EVIOCGKEYCODE: 550 if (get_user(t, ip)) 551 return -EFAULT; 552 553 error = input_get_keycode(dev, t, &v); 554 if (error) 555 return error; 556 557 if (put_user(v, ip + 1)) 558 return -EFAULT; 559 560 return 0; 561 562 case EVIOCSKEYCODE: 563 if (get_user(t, ip) || get_user(v, ip + 1)) 564 return -EFAULT; 565 566 return input_set_keycode(dev, t, v); 567 568 case EVIOCRMFF: 569 return input_ff_erase(dev, (int)(unsigned long) p, file); 570 571 case EVIOCGEFFECTS: 572 i = test_bit(EV_FF, dev->evbit) ? 573 dev->ff->max_effects : 0; 574 if (put_user(i, ip)) 575 return -EFAULT; 576 return 0; 577 578 case EVIOCGRAB: 579 if (p) 580 return evdev_grab(evdev, client); 581 else 582 return evdev_ungrab(evdev, client); 583 584 default: 585 586 if (_IOC_TYPE(cmd) != 'E') 587 return -EINVAL; 588 589 if (_IOC_DIR(cmd) == _IOC_READ) { 590 591 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0, 0))) 592 return handle_eviocgbit(dev, cmd, p, compat_mode); 593 594 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0))) 595 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd), 596 p, compat_mode); 597 598 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0))) 599 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd), 600 p, compat_mode); 601 602 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0))) 603 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd), 604 p, compat_mode); 605 606 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0))) 607 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd), 608 p, compat_mode); 609 610 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) 611 return str_to_user(dev->name, _IOC_SIZE(cmd), p); 612 613 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) 614 return str_to_user(dev->phys, _IOC_SIZE(cmd), p); 615 616 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) 617 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p); 618 619 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) { 620 621 t = _IOC_NR(cmd) & ABS_MAX; 622 623 abs.value = dev->abs[t]; 624 abs.minimum = dev->absmin[t]; 625 abs.maximum = dev->absmax[t]; 626 abs.fuzz = dev->absfuzz[t]; 627 abs.flat = dev->absflat[t]; 628 abs.resolution = dev->absres[t]; 629 630 if (copy_to_user(p, &abs, min_t(size_t, 631 _IOC_SIZE(cmd), 632 sizeof(struct input_absinfo)))) 633 return -EFAULT; 634 635 return 0; 636 } 637 638 } 639 640 if (_IOC_DIR(cmd) == _IOC_WRITE) { 641 642 if (_IOC_NR(cmd) == _IOC_NR(EVIOCSFF)) { 643 644 if (input_ff_effect_from_user(p, _IOC_SIZE(cmd), &effect)) 645 return -EFAULT; 646 647 error = input_ff_upload(dev, &effect, file); 648 649 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id))) 650 return -EFAULT; 651 652 return error; 653 } 654 655 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) { 656 657 t = _IOC_NR(cmd) & ABS_MAX; 658 659 if (copy_from_user(&abs, p, min_t(size_t, 660 _IOC_SIZE(cmd), 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 dev->absres[t] = _IOC_SIZE(cmd) < sizeof(struct input_absinfo) ? 677 0 : abs.resolution; 678 679 spin_unlock_irq(&dev->event_lock); 680 681 return 0; 682 } 683 } 684 } 685 return -EINVAL; 686 } 687 688 static long evdev_ioctl_handler(struct file *file, unsigned int cmd, 689 void __user *p, int compat_mode) 690 { 691 struct evdev_client *client = file->private_data; 692 struct evdev *evdev = client->evdev; 693 int retval; 694 695 retval = mutex_lock_interruptible(&evdev->mutex); 696 if (retval) 697 return retval; 698 699 if (!evdev->exist) { 700 retval = -ENODEV; 701 goto out; 702 } 703 704 retval = evdev_do_ioctl(file, cmd, p, compat_mode); 705 706 out: 707 mutex_unlock(&evdev->mutex); 708 return retval; 709 } 710 711 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 712 { 713 return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0); 714 } 715 716 #ifdef CONFIG_COMPAT 717 static long evdev_ioctl_compat(struct file *file, 718 unsigned int cmd, unsigned long arg) 719 { 720 return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1); 721 } 722 #endif 723 724 static const struct file_operations evdev_fops = { 725 .owner = THIS_MODULE, 726 .read = evdev_read, 727 .write = evdev_write, 728 .poll = evdev_poll, 729 .open = evdev_open, 730 .release = evdev_release, 731 .unlocked_ioctl = evdev_ioctl, 732 #ifdef CONFIG_COMPAT 733 .compat_ioctl = evdev_ioctl_compat, 734 #endif 735 .fasync = evdev_fasync, 736 .flush = evdev_flush 737 }; 738 739 static int evdev_install_chrdev(struct evdev *evdev) 740 { 741 /* 742 * No need to do any locking here as calls to connect and 743 * disconnect are serialized by the input core 744 */ 745 evdev_table[evdev->minor] = evdev; 746 return 0; 747 } 748 749 static void evdev_remove_chrdev(struct evdev *evdev) 750 { 751 /* 752 * Lock evdev table to prevent race with evdev_open() 753 */ 754 mutex_lock(&evdev_table_mutex); 755 evdev_table[evdev->minor] = NULL; 756 mutex_unlock(&evdev_table_mutex); 757 } 758 759 /* 760 * Mark device non-existent. This disables writes, ioctls and 761 * prevents new users from opening the device. Already posted 762 * blocking reads will stay, however new ones will fail. 763 */ 764 static void evdev_mark_dead(struct evdev *evdev) 765 { 766 mutex_lock(&evdev->mutex); 767 evdev->exist = 0; 768 mutex_unlock(&evdev->mutex); 769 } 770 771 static void evdev_cleanup(struct evdev *evdev) 772 { 773 struct input_handle *handle = &evdev->handle; 774 775 evdev_mark_dead(evdev); 776 evdev_hangup(evdev); 777 evdev_remove_chrdev(evdev); 778 779 /* evdev is marked dead so no one else accesses evdev->open */ 780 if (evdev->open) { 781 input_flush_device(handle, NULL); 782 input_close_device(handle); 783 } 784 } 785 786 /* 787 * Create new evdev device. Note that input core serializes calls 788 * to connect and disconnect so we don't need to lock evdev_table here. 789 */ 790 static int evdev_connect(struct input_handler *handler, struct input_dev *dev, 791 const struct input_device_id *id) 792 { 793 struct evdev *evdev; 794 int minor; 795 int error; 796 797 for (minor = 0; minor < EVDEV_MINORS; minor++) 798 if (!evdev_table[minor]) 799 break; 800 801 if (minor == EVDEV_MINORS) { 802 printk(KERN_ERR "evdev: no more free evdev devices\n"); 803 return -ENFILE; 804 } 805 806 evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL); 807 if (!evdev) 808 return -ENOMEM; 809 810 INIT_LIST_HEAD(&evdev->client_list); 811 spin_lock_init(&evdev->client_lock); 812 mutex_init(&evdev->mutex); 813 init_waitqueue_head(&evdev->wait); 814 815 dev_set_name(&evdev->dev, "event%d", minor); 816 evdev->exist = 1; 817 evdev->minor = minor; 818 819 evdev->handle.dev = input_get_device(dev); 820 evdev->handle.name = dev_name(&evdev->dev); 821 evdev->handle.handler = handler; 822 evdev->handle.private = evdev; 823 824 evdev->dev.devt = MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor); 825 evdev->dev.class = &input_class; 826 evdev->dev.parent = &dev->dev; 827 evdev->dev.release = evdev_free; 828 device_initialize(&evdev->dev); 829 830 error = input_register_handle(&evdev->handle); 831 if (error) 832 goto err_free_evdev; 833 834 error = evdev_install_chrdev(evdev); 835 if (error) 836 goto err_unregister_handle; 837 838 error = device_add(&evdev->dev); 839 if (error) 840 goto err_cleanup_evdev; 841 842 return 0; 843 844 err_cleanup_evdev: 845 evdev_cleanup(evdev); 846 err_unregister_handle: 847 input_unregister_handle(&evdev->handle); 848 err_free_evdev: 849 put_device(&evdev->dev); 850 return error; 851 } 852 853 static void evdev_disconnect(struct input_handle *handle) 854 { 855 struct evdev *evdev = handle->private; 856 857 device_del(&evdev->dev); 858 evdev_cleanup(evdev); 859 input_unregister_handle(handle); 860 put_device(&evdev->dev); 861 } 862 863 static const struct input_device_id evdev_ids[] = { 864 { .driver_info = 1 }, /* Matches all devices */ 865 { }, /* Terminating zero entry */ 866 }; 867 868 MODULE_DEVICE_TABLE(input, evdev_ids); 869 870 static struct input_handler evdev_handler = { 871 .event = evdev_event, 872 .connect = evdev_connect, 873 .disconnect = evdev_disconnect, 874 .fops = &evdev_fops, 875 .minor = EVDEV_MINOR_BASE, 876 .name = "evdev", 877 .id_table = evdev_ids, 878 }; 879 880 static int __init evdev_init(void) 881 { 882 return input_register_handler(&evdev_handler); 883 } 884 885 static void __exit evdev_exit(void) 886 { 887 input_unregister_handler(&evdev_handler); 888 } 889 890 module_init(evdev_init); 891 module_exit(evdev_exit); 892 893 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); 894 MODULE_DESCRIPTION("Input driver event char devices"); 895 MODULE_LICENSE("GPL"); 896