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 = kmalloc(sizeof(struct evdev_list), GFP_KERNEL))) 134 return -ENOMEM; 135 memset(list, 0, sizeof(struct evdev_list)); 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 #ifdef CONFIG_X86_64 158 # define COMPAT_TEST test_thread_flag(TIF_IA32) 159 #elif defined(CONFIG_IA64) 160 # define COMPAT_TEST IS_IA32_PROCESS(ia64_task_regs(current)) 161 #elif defined(CONFIG_S390) 162 # define COMPAT_TEST test_thread_flag(TIF_31BIT) 163 #elif defined(CONFIG_MIPS) 164 # define COMPAT_TEST (current->thread.mflags & MF_32BIT_ADDR) 165 #else 166 # define COMPAT_TEST test_thread_flag(TIF_32BIT) 167 #endif 168 169 static inline size_t evdev_event_size(void) 170 { 171 return COMPAT_TEST ? 172 sizeof(struct input_event_compat) : sizeof(struct input_event); 173 } 174 175 static int evdev_event_from_user(const char __user *buffer, struct input_event *event) 176 { 177 if (COMPAT_TEST) { 178 struct input_event_compat compat_event; 179 180 if (copy_from_user(&compat_event, buffer, sizeof(struct input_event_compat))) 181 return -EFAULT; 182 183 event->time.tv_sec = compat_event.time.tv_sec; 184 event->time.tv_usec = compat_event.time.tv_usec; 185 event->type = compat_event.type; 186 event->code = compat_event.code; 187 event->value = compat_event.value; 188 189 } else { 190 if (copy_from_user(event, buffer, sizeof(struct input_event))) 191 return -EFAULT; 192 } 193 194 return 0; 195 } 196 197 static int evdev_event_to_user(char __user *buffer, const struct input_event *event) 198 { 199 if (COMPAT_TEST) { 200 struct input_event_compat compat_event; 201 202 compat_event.time.tv_sec = event->time.tv_sec; 203 compat_event.time.tv_usec = event->time.tv_usec; 204 compat_event.type = event->type; 205 compat_event.code = event->code; 206 compat_event.value = event->value; 207 208 if (copy_to_user(buffer, &compat_event, sizeof(struct input_event_compat))) 209 return -EFAULT; 210 211 } else { 212 if (copy_to_user(buffer, event, sizeof(struct input_event))) 213 return -EFAULT; 214 } 215 216 return 0; 217 } 218 219 #else 220 221 static inline size_t evdev_event_size(void) 222 { 223 return sizeof(struct input_event); 224 } 225 226 static int evdev_event_from_user(const char __user *buffer, struct input_event *event) 227 { 228 if (copy_from_user(event, buffer, sizeof(struct input_event))) 229 return -EFAULT; 230 231 return 0; 232 } 233 234 static int evdev_event_to_user(char __user *buffer, const struct input_event *event) 235 { 236 if (copy_to_user(buffer, event, sizeof(struct input_event))) 237 return -EFAULT; 238 239 return 0; 240 } 241 242 #endif /* CONFIG_COMPAT */ 243 244 static ssize_t evdev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos) 245 { 246 struct evdev_list *list = file->private_data; 247 struct input_event event; 248 int retval = 0; 249 250 if (!list->evdev->exist) 251 return -ENODEV; 252 253 while (retval < count) { 254 255 if (evdev_event_from_user(buffer + retval, &event)) 256 return -EFAULT; 257 input_event(list->evdev->handle.dev, event.type, event.code, event.value); 258 retval += evdev_event_size(); 259 } 260 261 return retval; 262 } 263 264 static ssize_t evdev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos) 265 { 266 struct evdev_list *list = file->private_data; 267 int retval; 268 269 if (count < evdev_event_size()) 270 return -EINVAL; 271 272 if (list->head == list->tail && list->evdev->exist && (file->f_flags & O_NONBLOCK)) 273 return -EAGAIN; 274 275 retval = wait_event_interruptible(list->evdev->wait, 276 list->head != list->tail || (!list->evdev->exist)); 277 278 if (retval) 279 return retval; 280 281 if (!list->evdev->exist) 282 return -ENODEV; 283 284 while (list->head != list->tail && retval + evdev_event_size() <= count) { 285 286 struct input_event *event = (struct input_event *) list->buffer + list->tail; 287 288 if (evdev_event_to_user(buffer + retval, event)) 289 return -EFAULT; 290 291 list->tail = (list->tail + 1) & (EVDEV_BUFFER_SIZE - 1); 292 retval += evdev_event_size(); 293 } 294 295 return retval; 296 } 297 298 /* No kernel lock - fine */ 299 static unsigned int evdev_poll(struct file *file, poll_table *wait) 300 { 301 struct evdev_list *list = file->private_data; 302 poll_wait(file, &list->evdev->wait, wait); 303 return ((list->head == list->tail) ? 0 : (POLLIN | POLLRDNORM)) | 304 (list->evdev->exist ? 0 : (POLLHUP | POLLERR)); 305 } 306 307 #ifdef CONFIG_COMPAT 308 309 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8) 310 #define NBITS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1) 311 312 #ifdef __BIG_ENDIAN 313 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 314 unsigned int maxlen, void __user *p, int compat) 315 { 316 int len, i; 317 318 if (compat) { 319 len = NBITS_COMPAT(maxbit) * sizeof(compat_long_t); 320 if (len < maxlen) 321 len = maxlen; 322 323 for (i = 0; i < len / sizeof(compat_long_t); i++) 324 if (copy_to_user((compat_long_t __user *) p + i, 325 (compat_long_t *) bits + 326 i + 1 - ((i % 2) << 1), 327 sizeof(compat_long_t))) 328 return -EFAULT; 329 } else { 330 len = NBITS(maxbit) * sizeof(long); 331 if (len > maxlen) 332 len = maxlen; 333 334 if (copy_to_user(p, bits, len)) 335 return -EFAULT; 336 } 337 338 return len; 339 } 340 #else 341 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 342 unsigned int maxlen, void __user *p, int compat) 343 { 344 int len = compat ? 345 NBITS_COMPAT(maxbit) * sizeof(compat_long_t) : 346 NBITS(maxbit) * sizeof(long); 347 348 if (len > maxlen) 349 len = maxlen; 350 351 return copy_to_user(p, bits, len) ? -EFAULT : len; 352 } 353 #endif /* __BIG_ENDIAN */ 354 355 #else 356 357 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 358 unsigned int maxlen, void __user *p, int compat) 359 { 360 int len = NBITS(maxbit) * sizeof(long); 361 362 if (len > maxlen) 363 len = maxlen; 364 365 return copy_to_user(p, bits, len) ? -EFAULT : len; 366 } 367 368 #endif /* CONFIG_COMPAT */ 369 370 static int str_to_user(const char *str, unsigned int maxlen, void __user *p) 371 { 372 int len; 373 374 if (!str) 375 return -ENOENT; 376 377 len = strlen(str) + 1; 378 if (len > maxlen) 379 len = maxlen; 380 381 return copy_to_user(p, str, len) ? -EFAULT : len; 382 } 383 384 static long evdev_ioctl_handler(struct file *file, unsigned int cmd, 385 void __user *p, int compat_mode) 386 { 387 struct evdev_list *list = file->private_data; 388 struct evdev *evdev = list->evdev; 389 struct input_dev *dev = evdev->handle.dev; 390 struct input_absinfo abs; 391 int __user *ip = (int __user *)p; 392 int i, t, u, v; 393 394 if (!evdev->exist) 395 return -ENODEV; 396 397 switch (cmd) { 398 399 case EVIOCGVERSION: 400 return put_user(EV_VERSION, ip); 401 402 case EVIOCGID: 403 if (copy_to_user(p, &dev->id, sizeof(struct input_id))) 404 return -EFAULT; 405 406 return 0; 407 408 case EVIOCGKEYCODE: 409 if (get_user(t, ip)) 410 return -EFAULT; 411 if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) 412 return -EINVAL; 413 if (put_user(INPUT_KEYCODE(dev, t), ip + 1)) 414 return -EFAULT; 415 return 0; 416 417 case EVIOCSKEYCODE: 418 if (get_user(t, ip)) 419 return -EFAULT; 420 if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) 421 return -EINVAL; 422 if (get_user(v, ip + 1)) 423 return -EFAULT; 424 if (v < 0 || v > KEY_MAX) 425 return -EINVAL; 426 if (dev->keycodesize < sizeof(v) && (v >> (dev->keycodesize * 8))) 427 return -EINVAL; 428 429 u = SET_INPUT_KEYCODE(dev, t, v); 430 clear_bit(u, dev->keybit); 431 set_bit(v, dev->keybit); 432 for (i = 0; i < dev->keycodemax; i++) 433 if (INPUT_KEYCODE(dev, i) == u) 434 set_bit(u, dev->keybit); 435 436 return 0; 437 438 case EVIOCSFF: 439 if (dev->upload_effect) { 440 struct ff_effect effect; 441 int err; 442 443 if (copy_from_user(&effect, p, sizeof(effect))) 444 return -EFAULT; 445 err = dev->upload_effect(dev, &effect); 446 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id))) 447 return -EFAULT; 448 return err; 449 } else 450 return -ENOSYS; 451 452 case EVIOCRMFF: 453 if (!dev->erase_effect) 454 return -ENOSYS; 455 456 return dev->erase_effect(dev, (int)(unsigned long) p); 457 458 case EVIOCGEFFECTS: 459 if (put_user(dev->ff_effects_max, ip)) 460 return -EFAULT; 461 return 0; 462 463 case EVIOCGRAB: 464 if (p) { 465 if (evdev->grab) 466 return -EBUSY; 467 if (input_grab_device(&evdev->handle)) 468 return -EBUSY; 469 evdev->grab = list; 470 return 0; 471 } else { 472 if (evdev->grab != list) 473 return -EINVAL; 474 input_release_device(&evdev->handle); 475 evdev->grab = NULL; 476 return 0; 477 } 478 479 default: 480 481 if (_IOC_TYPE(cmd) != 'E') 482 return -EINVAL; 483 484 if (_IOC_DIR(cmd) == _IOC_READ) { 485 486 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) { 487 488 long *bits; 489 int len; 490 491 switch (_IOC_NR(cmd) & EV_MAX) { 492 case 0: bits = dev->evbit; len = EV_MAX; break; 493 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break; 494 case EV_REL: bits = dev->relbit; len = REL_MAX; break; 495 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break; 496 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break; 497 case EV_LED: bits = dev->ledbit; len = LED_MAX; break; 498 case EV_SND: bits = dev->sndbit; len = SND_MAX; break; 499 case EV_FF: bits = dev->ffbit; len = FF_MAX; break; 500 case EV_SW: bits = dev->swbit; len = SW_MAX; break; 501 default: return -EINVAL; 502 } 503 return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode); 504 } 505 506 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0))) 507 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd), 508 p, compat_mode); 509 510 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0))) 511 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd), 512 p, compat_mode); 513 514 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0))) 515 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd), 516 p, compat_mode); 517 518 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0))) 519 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd), 520 p, compat_mode); 521 522 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) 523 return str_to_user(dev->name, _IOC_SIZE(cmd), p); 524 525 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) 526 return str_to_user(dev->phys, _IOC_SIZE(cmd), p); 527 528 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) 529 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p); 530 531 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) { 532 533 int t = _IOC_NR(cmd) & ABS_MAX; 534 535 abs.value = dev->abs[t]; 536 abs.minimum = dev->absmin[t]; 537 abs.maximum = dev->absmax[t]; 538 abs.fuzz = dev->absfuzz[t]; 539 abs.flat = dev->absflat[t]; 540 541 if (copy_to_user(p, &abs, sizeof(struct input_absinfo))) 542 return -EFAULT; 543 544 return 0; 545 } 546 547 } 548 549 if (_IOC_DIR(cmd) == _IOC_WRITE) { 550 551 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) { 552 553 int t = _IOC_NR(cmd) & ABS_MAX; 554 555 if (copy_from_user(&abs, p, sizeof(struct input_absinfo))) 556 return -EFAULT; 557 558 dev->abs[t] = abs.value; 559 dev->absmin[t] = abs.minimum; 560 dev->absmax[t] = abs.maximum; 561 dev->absfuzz[t] = abs.fuzz; 562 dev->absflat[t] = abs.flat; 563 564 return 0; 565 } 566 } 567 } 568 return -EINVAL; 569 } 570 571 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 572 { 573 return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0); 574 } 575 576 #ifdef CONFIG_COMPAT 577 static long evdev_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg) 578 { 579 return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1); 580 } 581 #endif 582 583 static struct file_operations evdev_fops = { 584 .owner = THIS_MODULE, 585 .read = evdev_read, 586 .write = evdev_write, 587 .poll = evdev_poll, 588 .open = evdev_open, 589 .release = evdev_release, 590 .unlocked_ioctl = evdev_ioctl, 591 #ifdef CONFIG_COMPAT 592 .compat_ioctl = evdev_ioctl_compat, 593 #endif 594 .fasync = evdev_fasync, 595 .flush = evdev_flush 596 }; 597 598 static struct input_handle *evdev_connect(struct input_handler *handler, struct input_dev *dev, struct input_device_id *id) 599 { 600 struct evdev *evdev; 601 struct class_device *cdev; 602 int minor; 603 604 for (minor = 0; minor < EVDEV_MINORS && evdev_table[minor]; minor++); 605 if (minor == EVDEV_MINORS) { 606 printk(KERN_ERR "evdev: no more free evdev devices\n"); 607 return NULL; 608 } 609 610 if (!(evdev = kmalloc(sizeof(struct evdev), GFP_KERNEL))) 611 return NULL; 612 memset(evdev, 0, sizeof(struct evdev)); 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