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