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