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/smp_lock.h> 22 #include <linux/device.h> 23 #include <linux/compat.h> 24 25 struct evdev { 26 int exist; 27 int open; 28 int minor; 29 char name[16]; 30 struct input_handle handle; 31 wait_queue_head_t wait; 32 struct evdev_list *grab; 33 struct list_head list; 34 }; 35 36 struct evdev_list { 37 struct input_event buffer[EVDEV_BUFFER_SIZE]; 38 int head; 39 int tail; 40 struct fasync_struct *fasync; 41 struct evdev *evdev; 42 struct list_head node; 43 }; 44 45 static struct evdev *evdev_table[EVDEV_MINORS]; 46 47 static void evdev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value) 48 { 49 struct evdev *evdev = handle->private; 50 struct evdev_list *list; 51 52 if (evdev->grab) { 53 list = evdev->grab; 54 55 do_gettimeofday(&list->buffer[list->head].time); 56 list->buffer[list->head].type = type; 57 list->buffer[list->head].code = code; 58 list->buffer[list->head].value = value; 59 list->head = (list->head + 1) & (EVDEV_BUFFER_SIZE - 1); 60 61 kill_fasync(&list->fasync, SIGIO, POLL_IN); 62 } else 63 list_for_each_entry(list, &evdev->list, node) { 64 65 do_gettimeofday(&list->buffer[list->head].time); 66 list->buffer[list->head].type = type; 67 list->buffer[list->head].code = code; 68 list->buffer[list->head].value = value; 69 list->head = (list->head + 1) & (EVDEV_BUFFER_SIZE - 1); 70 71 kill_fasync(&list->fasync, SIGIO, POLL_IN); 72 } 73 74 wake_up_interruptible(&evdev->wait); 75 } 76 77 static int evdev_fasync(int fd, struct file *file, int on) 78 { 79 int retval; 80 struct evdev_list *list = file->private_data; 81 82 retval = fasync_helper(fd, file, on, &list->fasync); 83 84 return retval < 0 ? retval : 0; 85 } 86 87 static int evdev_flush(struct file *file, fl_owner_t id) 88 { 89 struct evdev_list *list = file->private_data; 90 91 if (!list->evdev->exist) 92 return -ENODEV; 93 94 return input_flush_device(&list->evdev->handle, file); 95 } 96 97 static void evdev_free(struct evdev *evdev) 98 { 99 evdev_table[evdev->minor] = NULL; 100 kfree(evdev); 101 } 102 103 static int evdev_release(struct inode * inode, struct file * file) 104 { 105 struct evdev_list *list = file->private_data; 106 107 if (list->evdev->grab == list) { 108 input_release_device(&list->evdev->handle); 109 list->evdev->grab = NULL; 110 } 111 112 evdev_fasync(-1, file, 0); 113 list_del(&list->node); 114 115 if (!--list->evdev->open) { 116 if (list->evdev->exist) 117 input_close_device(&list->evdev->handle); 118 else 119 evdev_free(list->evdev); 120 } 121 122 kfree(list); 123 return 0; 124 } 125 126 static int evdev_open(struct inode * inode, struct file * file) 127 { 128 struct evdev_list *list; 129 int i = iminor(inode) - EVDEV_MINOR_BASE; 130 int accept_err; 131 132 if (i >= EVDEV_MINORS || !evdev_table[i] || !evdev_table[i]->exist) 133 return -ENODEV; 134 135 if ((accept_err = input_accept_process(&(evdev_table[i]->handle), file))) 136 return accept_err; 137 138 if (!(list = kzalloc(sizeof(struct evdev_list), GFP_KERNEL))) 139 return -ENOMEM; 140 141 list->evdev = evdev_table[i]; 142 list_add_tail(&list->node, &evdev_table[i]->list); 143 file->private_data = list; 144 145 if (!list->evdev->open++) 146 if (list->evdev->exist) 147 input_open_device(&list->evdev->handle); 148 149 return 0; 150 } 151 152 #ifdef CONFIG_COMPAT 153 154 struct input_event_compat { 155 struct compat_timeval time; 156 __u16 type; 157 __u16 code; 158 __s32 value; 159 }; 160 161 /* Note to the author of this code: did it ever occur to 162 you why the ifdefs are needed? Think about it again. -AK */ 163 #ifdef CONFIG_X86_64 164 # define COMPAT_TEST is_compat_task() 165 #elif defined(CONFIG_IA64) 166 # define COMPAT_TEST IS_IA32_PROCESS(task_pt_regs(current)) 167 #elif defined(CONFIG_S390) 168 # define COMPAT_TEST test_thread_flag(TIF_31BIT) 169 #elif defined(CONFIG_MIPS) 170 # define COMPAT_TEST (current->thread.mflags & MF_32BIT_ADDR) 171 #else 172 # define COMPAT_TEST test_thread_flag(TIF_32BIT) 173 #endif 174 175 static inline size_t evdev_event_size(void) 176 { 177 return COMPAT_TEST ? 178 sizeof(struct input_event_compat) : sizeof(struct input_event); 179 } 180 181 static int evdev_event_from_user(const char __user *buffer, struct input_event *event) 182 { 183 if (COMPAT_TEST) { 184 struct input_event_compat compat_event; 185 186 if (copy_from_user(&compat_event, buffer, sizeof(struct input_event_compat))) 187 return -EFAULT; 188 189 event->time.tv_sec = compat_event.time.tv_sec; 190 event->time.tv_usec = compat_event.time.tv_usec; 191 event->type = compat_event.type; 192 event->code = compat_event.code; 193 event->value = compat_event.value; 194 195 } else { 196 if (copy_from_user(event, buffer, sizeof(struct input_event))) 197 return -EFAULT; 198 } 199 200 return 0; 201 } 202 203 static int evdev_event_to_user(char __user *buffer, const struct input_event *event) 204 { 205 if (COMPAT_TEST) { 206 struct input_event_compat compat_event; 207 208 compat_event.time.tv_sec = event->time.tv_sec; 209 compat_event.time.tv_usec = event->time.tv_usec; 210 compat_event.type = event->type; 211 compat_event.code = event->code; 212 compat_event.value = event->value; 213 214 if (copy_to_user(buffer, &compat_event, sizeof(struct input_event_compat))) 215 return -EFAULT; 216 217 } else { 218 if (copy_to_user(buffer, event, sizeof(struct input_event))) 219 return -EFAULT; 220 } 221 222 return 0; 223 } 224 225 #else 226 227 static inline size_t evdev_event_size(void) 228 { 229 return sizeof(struct input_event); 230 } 231 232 static int evdev_event_from_user(const char __user *buffer, struct input_event *event) 233 { 234 if (copy_from_user(event, buffer, sizeof(struct input_event))) 235 return -EFAULT; 236 237 return 0; 238 } 239 240 static int evdev_event_to_user(char __user *buffer, const struct input_event *event) 241 { 242 if (copy_to_user(buffer, event, sizeof(struct input_event))) 243 return -EFAULT; 244 245 return 0; 246 } 247 248 #endif /* CONFIG_COMPAT */ 249 250 static ssize_t evdev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos) 251 { 252 struct evdev_list *list = file->private_data; 253 struct input_event event; 254 int retval = 0; 255 256 if (!list->evdev->exist) 257 return -ENODEV; 258 259 while (retval < count) { 260 261 if (evdev_event_from_user(buffer + retval, &event)) 262 return -EFAULT; 263 input_event(list->evdev->handle.dev, event.type, event.code, event.value); 264 retval += evdev_event_size(); 265 } 266 267 return retval; 268 } 269 270 static ssize_t evdev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos) 271 { 272 struct evdev_list *list = file->private_data; 273 int retval; 274 275 if (count < evdev_event_size()) 276 return -EINVAL; 277 278 if (list->head == list->tail && list->evdev->exist && (file->f_flags & O_NONBLOCK)) 279 return -EAGAIN; 280 281 retval = wait_event_interruptible(list->evdev->wait, 282 list->head != list->tail || (!list->evdev->exist)); 283 284 if (retval) 285 return retval; 286 287 if (!list->evdev->exist) 288 return -ENODEV; 289 290 while (list->head != list->tail && retval + evdev_event_size() <= count) { 291 292 struct input_event *event = (struct input_event *) list->buffer + list->tail; 293 294 if (evdev_event_to_user(buffer + retval, event)) 295 return -EFAULT; 296 297 list->tail = (list->tail + 1) & (EVDEV_BUFFER_SIZE - 1); 298 retval += evdev_event_size(); 299 } 300 301 return retval; 302 } 303 304 /* No kernel lock - fine */ 305 static unsigned int evdev_poll(struct file *file, poll_table *wait) 306 { 307 struct evdev_list *list = file->private_data; 308 309 poll_wait(file, &list->evdev->wait, wait); 310 return ((list->head == list->tail) ? 0 : (POLLIN | POLLRDNORM)) | 311 (list->evdev->exist ? 0 : (POLLHUP | POLLERR)); 312 } 313 314 #ifdef CONFIG_COMPAT 315 316 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8) 317 #define NBITS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1) 318 319 #ifdef __BIG_ENDIAN 320 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 321 unsigned int maxlen, void __user *p, int compat) 322 { 323 int len, i; 324 325 if (compat) { 326 len = NBITS_COMPAT(maxbit) * sizeof(compat_long_t); 327 if (len < maxlen) 328 len = maxlen; 329 330 for (i = 0; i < len / sizeof(compat_long_t); i++) 331 if (copy_to_user((compat_long_t __user *) p + i, 332 (compat_long_t *) bits + 333 i + 1 - ((i % 2) << 1), 334 sizeof(compat_long_t))) 335 return -EFAULT; 336 } else { 337 len = NBITS(maxbit) * sizeof(long); 338 if (len > maxlen) 339 len = maxlen; 340 341 if (copy_to_user(p, bits, len)) 342 return -EFAULT; 343 } 344 345 return len; 346 } 347 #else 348 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 349 unsigned int maxlen, void __user *p, int compat) 350 { 351 int len = compat ? 352 NBITS_COMPAT(maxbit) * sizeof(compat_long_t) : 353 NBITS(maxbit) * sizeof(long); 354 355 if (len > maxlen) 356 len = maxlen; 357 358 return copy_to_user(p, bits, len) ? -EFAULT : len; 359 } 360 #endif /* __BIG_ENDIAN */ 361 362 #else 363 364 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 365 unsigned int maxlen, void __user *p, int compat) 366 { 367 int len = NBITS(maxbit) * sizeof(long); 368 369 if (len > maxlen) 370 len = maxlen; 371 372 return copy_to_user(p, bits, len) ? -EFAULT : len; 373 } 374 375 #endif /* CONFIG_COMPAT */ 376 377 static int str_to_user(const char *str, unsigned int maxlen, void __user *p) 378 { 379 int len; 380 381 if (!str) 382 return -ENOENT; 383 384 len = strlen(str) + 1; 385 if (len > maxlen) 386 len = maxlen; 387 388 return copy_to_user(p, str, len) ? -EFAULT : len; 389 } 390 391 static long evdev_ioctl_handler(struct file *file, unsigned int cmd, 392 void __user *p, int compat_mode) 393 { 394 struct evdev_list *list = file->private_data; 395 struct evdev *evdev = list->evdev; 396 struct input_dev *dev = evdev->handle.dev; 397 struct input_absinfo abs; 398 int __user *ip = (int __user *)p; 399 int i, t, u, v; 400 401 if (!evdev->exist) 402 return -ENODEV; 403 404 switch (cmd) { 405 406 case EVIOCGVERSION: 407 return put_user(EV_VERSION, ip); 408 409 case EVIOCGID: 410 if (copy_to_user(p, &dev->id, sizeof(struct input_id))) 411 return -EFAULT; 412 return 0; 413 414 case EVIOCGREP: 415 if (!test_bit(EV_REP, dev->evbit)) 416 return -ENOSYS; 417 if (put_user(dev->rep[REP_DELAY], ip)) 418 return -EFAULT; 419 if (put_user(dev->rep[REP_PERIOD], ip + 1)) 420 return -EFAULT; 421 return 0; 422 423 case EVIOCSREP: 424 if (!test_bit(EV_REP, dev->evbit)) 425 return -ENOSYS; 426 if (get_user(u, ip)) 427 return -EFAULT; 428 if (get_user(v, ip + 1)) 429 return -EFAULT; 430 431 input_event(dev, EV_REP, REP_DELAY, u); 432 input_event(dev, EV_REP, REP_PERIOD, v); 433 434 return 0; 435 436 case EVIOCGKEYCODE: 437 if (get_user(t, ip)) 438 return -EFAULT; 439 if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) 440 return -EINVAL; 441 if (put_user(INPUT_KEYCODE(dev, t), ip + 1)) 442 return -EFAULT; 443 return 0; 444 445 case EVIOCSKEYCODE: 446 if (get_user(t, ip)) 447 return -EFAULT; 448 if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) 449 return -EINVAL; 450 if (get_user(v, ip + 1)) 451 return -EFAULT; 452 if (v < 0 || v > KEY_MAX) 453 return -EINVAL; 454 if (dev->keycodesize < sizeof(v) && (v >> (dev->keycodesize * 8))) 455 return -EINVAL; 456 457 u = SET_INPUT_KEYCODE(dev, t, v); 458 clear_bit(u, dev->keybit); 459 set_bit(v, dev->keybit); 460 for (i = 0; i < dev->keycodemax; i++) 461 if (INPUT_KEYCODE(dev, i) == u) 462 set_bit(u, dev->keybit); 463 464 return 0; 465 466 case EVIOCSFF: 467 if (dev->upload_effect) { 468 struct ff_effect effect; 469 int err; 470 471 if (copy_from_user(&effect, p, sizeof(effect))) 472 return -EFAULT; 473 err = dev->upload_effect(dev, &effect); 474 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id))) 475 return -EFAULT; 476 return err; 477 } else 478 return -ENOSYS; 479 480 case EVIOCRMFF: 481 if (!dev->erase_effect) 482 return -ENOSYS; 483 484 return dev->erase_effect(dev, (int)(unsigned long) p); 485 486 case EVIOCGEFFECTS: 487 if (put_user(dev->ff_effects_max, ip)) 488 return -EFAULT; 489 return 0; 490 491 case EVIOCGRAB: 492 if (p) { 493 if (evdev->grab) 494 return -EBUSY; 495 if (input_grab_device(&evdev->handle)) 496 return -EBUSY; 497 evdev->grab = list; 498 return 0; 499 } else { 500 if (evdev->grab != list) 501 return -EINVAL; 502 input_release_device(&evdev->handle); 503 evdev->grab = NULL; 504 return 0; 505 } 506 507 default: 508 509 if (_IOC_TYPE(cmd) != 'E') 510 return -EINVAL; 511 512 if (_IOC_DIR(cmd) == _IOC_READ) { 513 514 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) { 515 516 long *bits; 517 int len; 518 519 switch (_IOC_NR(cmd) & EV_MAX) { 520 case 0: bits = dev->evbit; len = EV_MAX; break; 521 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break; 522 case EV_REL: bits = dev->relbit; len = REL_MAX; break; 523 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break; 524 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break; 525 case EV_LED: bits = dev->ledbit; len = LED_MAX; break; 526 case EV_SND: bits = dev->sndbit; len = SND_MAX; break; 527 case EV_FF: bits = dev->ffbit; len = FF_MAX; break; 528 case EV_SW: bits = dev->swbit; len = SW_MAX; break; 529 default: return -EINVAL; 530 } 531 return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode); 532 } 533 534 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0))) 535 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd), 536 p, compat_mode); 537 538 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0))) 539 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd), 540 p, compat_mode); 541 542 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0))) 543 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd), 544 p, compat_mode); 545 546 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0))) 547 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd), 548 p, compat_mode); 549 550 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) 551 return str_to_user(dev->name, _IOC_SIZE(cmd), p); 552 553 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) 554 return str_to_user(dev->phys, _IOC_SIZE(cmd), p); 555 556 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) 557 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p); 558 559 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) { 560 561 int t = _IOC_NR(cmd) & ABS_MAX; 562 563 abs.value = dev->abs[t]; 564 abs.minimum = dev->absmin[t]; 565 abs.maximum = dev->absmax[t]; 566 abs.fuzz = dev->absfuzz[t]; 567 abs.flat = dev->absflat[t]; 568 569 if (copy_to_user(p, &abs, sizeof(struct input_absinfo))) 570 return -EFAULT; 571 572 return 0; 573 } 574 575 } 576 577 if (_IOC_DIR(cmd) == _IOC_WRITE) { 578 579 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) { 580 581 int t = _IOC_NR(cmd) & ABS_MAX; 582 583 if (copy_from_user(&abs, p, sizeof(struct input_absinfo))) 584 return -EFAULT; 585 586 dev->abs[t] = abs.value; 587 dev->absmin[t] = abs.minimum; 588 dev->absmax[t] = abs.maximum; 589 dev->absfuzz[t] = abs.fuzz; 590 dev->absflat[t] = abs.flat; 591 592 return 0; 593 } 594 } 595 } 596 return -EINVAL; 597 } 598 599 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 600 { 601 return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0); 602 } 603 604 #ifdef CONFIG_COMPAT 605 static long evdev_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg) 606 { 607 return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1); 608 } 609 #endif 610 611 static struct file_operations evdev_fops = { 612 .owner = THIS_MODULE, 613 .read = evdev_read, 614 .write = evdev_write, 615 .poll = evdev_poll, 616 .open = evdev_open, 617 .release = evdev_release, 618 .unlocked_ioctl = evdev_ioctl, 619 #ifdef CONFIG_COMPAT 620 .compat_ioctl = evdev_ioctl_compat, 621 #endif 622 .fasync = evdev_fasync, 623 .flush = evdev_flush 624 }; 625 626 static struct input_handle *evdev_connect(struct input_handler *handler, struct input_dev *dev, struct input_device_id *id) 627 { 628 struct evdev *evdev; 629 struct class_device *cdev; 630 int minor; 631 632 for (minor = 0; minor < EVDEV_MINORS && evdev_table[minor]; minor++); 633 if (minor == EVDEV_MINORS) { 634 printk(KERN_ERR "evdev: no more free evdev devices\n"); 635 return NULL; 636 } 637 638 if (!(evdev = kzalloc(sizeof(struct evdev), GFP_KERNEL))) 639 return NULL; 640 641 INIT_LIST_HEAD(&evdev->list); 642 init_waitqueue_head(&evdev->wait); 643 644 evdev->exist = 1; 645 evdev->minor = minor; 646 evdev->handle.dev = dev; 647 evdev->handle.name = evdev->name; 648 evdev->handle.handler = handler; 649 evdev->handle.private = evdev; 650 sprintf(evdev->name, "event%d", minor); 651 652 evdev_table[minor] = evdev; 653 654 cdev = class_device_create(&input_class, &dev->cdev, 655 MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor), 656 dev->cdev.dev, evdev->name); 657 658 /* temporary symlink to keep userspace happy */ 659 sysfs_create_link(&input_class.subsys.kset.kobj, &cdev->kobj, 660 evdev->name); 661 662 return &evdev->handle; 663 } 664 665 static void evdev_disconnect(struct input_handle *handle) 666 { 667 struct evdev *evdev = handle->private; 668 struct evdev_list *list; 669 670 sysfs_remove_link(&input_class.subsys.kset.kobj, evdev->name); 671 class_device_destroy(&input_class, 672 MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + evdev->minor)); 673 evdev->exist = 0; 674 675 if (evdev->open) { 676 input_close_device(handle); 677 wake_up_interruptible(&evdev->wait); 678 list_for_each_entry(list, &evdev->list, node) 679 kill_fasync(&list->fasync, SIGIO, POLL_HUP); 680 } else 681 evdev_free(evdev); 682 } 683 684 static struct input_device_id evdev_ids[] = { 685 { .driver_info = 1 }, /* Matches all devices */ 686 { }, /* Terminating zero entry */ 687 }; 688 689 MODULE_DEVICE_TABLE(input, evdev_ids); 690 691 static struct input_handler evdev_handler = { 692 .event = evdev_event, 693 .connect = evdev_connect, 694 .disconnect = evdev_disconnect, 695 .fops = &evdev_fops, 696 .minor = EVDEV_MINOR_BASE, 697 .name = "evdev", 698 .id_table = evdev_ids, 699 }; 700 701 static int __init evdev_init(void) 702 { 703 input_register_handler(&evdev_handler); 704 return 0; 705 } 706 707 static void __exit evdev_exit(void) 708 { 709 input_unregister_handler(&evdev_handler); 710 } 711 712 module_init(evdev_init); 713 module_exit(evdev_exit); 714 715 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); 716 MODULE_DESCRIPTION("Input driver event char devices"); 717 MODULE_LICENSE("GPL"); 718