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 /* 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_event(list->evdev->handle.dev, 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 poll_wait(file, &list->evdev->wait, wait); 305 return ((list->head == list->tail) ? 0 : (POLLIN | POLLRDNORM)) | 306 (list->evdev->exist ? 0 : (POLLHUP | POLLERR)); 307 } 308 309 #ifdef CONFIG_COMPAT 310 311 #define BITS_PER_LONG_COMPAT (sizeof(compat_long_t) * 8) 312 #define NBITS_COMPAT(x) ((((x) - 1) / BITS_PER_LONG_COMPAT) + 1) 313 314 #ifdef __BIG_ENDIAN 315 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 316 unsigned int maxlen, void __user *p, int compat) 317 { 318 int len, i; 319 320 if (compat) { 321 len = NBITS_COMPAT(maxbit) * sizeof(compat_long_t); 322 if (len < maxlen) 323 len = maxlen; 324 325 for (i = 0; i < len / sizeof(compat_long_t); i++) 326 if (copy_to_user((compat_long_t __user *) p + i, 327 (compat_long_t *) bits + 328 i + 1 - ((i % 2) << 1), 329 sizeof(compat_long_t))) 330 return -EFAULT; 331 } else { 332 len = NBITS(maxbit) * sizeof(long); 333 if (len > maxlen) 334 len = maxlen; 335 336 if (copy_to_user(p, bits, len)) 337 return -EFAULT; 338 } 339 340 return len; 341 } 342 #else 343 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 344 unsigned int maxlen, void __user *p, int compat) 345 { 346 int len = compat ? 347 NBITS_COMPAT(maxbit) * sizeof(compat_long_t) : 348 NBITS(maxbit) * sizeof(long); 349 350 if (len > maxlen) 351 len = maxlen; 352 353 return copy_to_user(p, bits, len) ? -EFAULT : len; 354 } 355 #endif /* __BIG_ENDIAN */ 356 357 #else 358 359 static int bits_to_user(unsigned long *bits, unsigned int maxbit, 360 unsigned int maxlen, void __user *p, int compat) 361 { 362 int len = NBITS(maxbit) * sizeof(long); 363 364 if (len > maxlen) 365 len = maxlen; 366 367 return copy_to_user(p, bits, len) ? -EFAULT : len; 368 } 369 370 #endif /* CONFIG_COMPAT */ 371 372 static int str_to_user(const char *str, unsigned int maxlen, void __user *p) 373 { 374 int len; 375 376 if (!str) 377 return -ENOENT; 378 379 len = strlen(str) + 1; 380 if (len > maxlen) 381 len = maxlen; 382 383 return copy_to_user(p, str, len) ? -EFAULT : len; 384 } 385 386 static long evdev_ioctl_handler(struct file *file, unsigned int cmd, 387 void __user *p, int compat_mode) 388 { 389 struct evdev_list *list = file->private_data; 390 struct evdev *evdev = list->evdev; 391 struct input_dev *dev = evdev->handle.dev; 392 struct input_absinfo abs; 393 int __user *ip = (int __user *)p; 394 int i, t, u, v; 395 396 if (!evdev->exist) 397 return -ENODEV; 398 399 switch (cmd) { 400 401 case EVIOCGVERSION: 402 return put_user(EV_VERSION, ip); 403 404 case EVIOCGID: 405 if (copy_to_user(p, &dev->id, sizeof(struct input_id))) 406 return -EFAULT; 407 408 return 0; 409 410 case EVIOCGKEYCODE: 411 if (get_user(t, ip)) 412 return -EFAULT; 413 if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) 414 return -EINVAL; 415 if (put_user(INPUT_KEYCODE(dev, t), ip + 1)) 416 return -EFAULT; 417 return 0; 418 419 case EVIOCSKEYCODE: 420 if (get_user(t, ip)) 421 return -EFAULT; 422 if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) 423 return -EINVAL; 424 if (get_user(v, ip + 1)) 425 return -EFAULT; 426 if (v < 0 || v > KEY_MAX) 427 return -EINVAL; 428 if (dev->keycodesize < sizeof(v) && (v >> (dev->keycodesize * 8))) 429 return -EINVAL; 430 431 u = SET_INPUT_KEYCODE(dev, t, v); 432 clear_bit(u, dev->keybit); 433 set_bit(v, dev->keybit); 434 for (i = 0; i < dev->keycodemax; i++) 435 if (INPUT_KEYCODE(dev, i) == u) 436 set_bit(u, dev->keybit); 437 438 return 0; 439 440 case EVIOCSFF: 441 if (dev->upload_effect) { 442 struct ff_effect effect; 443 int err; 444 445 if (copy_from_user(&effect, p, sizeof(effect))) 446 return -EFAULT; 447 err = dev->upload_effect(dev, &effect); 448 if (put_user(effect.id, &(((struct ff_effect __user *)p)->id))) 449 return -EFAULT; 450 return err; 451 } else 452 return -ENOSYS; 453 454 case EVIOCRMFF: 455 if (!dev->erase_effect) 456 return -ENOSYS; 457 458 return dev->erase_effect(dev, (int)(unsigned long) p); 459 460 case EVIOCGEFFECTS: 461 if (put_user(dev->ff_effects_max, ip)) 462 return -EFAULT; 463 return 0; 464 465 case EVIOCGRAB: 466 if (p) { 467 if (evdev->grab) 468 return -EBUSY; 469 if (input_grab_device(&evdev->handle)) 470 return -EBUSY; 471 evdev->grab = list; 472 return 0; 473 } else { 474 if (evdev->grab != list) 475 return -EINVAL; 476 input_release_device(&evdev->handle); 477 evdev->grab = NULL; 478 return 0; 479 } 480 481 default: 482 483 if (_IOC_TYPE(cmd) != 'E') 484 return -EINVAL; 485 486 if (_IOC_DIR(cmd) == _IOC_READ) { 487 488 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) { 489 490 long *bits; 491 int len; 492 493 switch (_IOC_NR(cmd) & EV_MAX) { 494 case 0: bits = dev->evbit; len = EV_MAX; break; 495 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break; 496 case EV_REL: bits = dev->relbit; len = REL_MAX; break; 497 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break; 498 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break; 499 case EV_LED: bits = dev->ledbit; len = LED_MAX; break; 500 case EV_SND: bits = dev->sndbit; len = SND_MAX; break; 501 case EV_FF: bits = dev->ffbit; len = FF_MAX; break; 502 case EV_SW: bits = dev->swbit; len = SW_MAX; break; 503 default: return -EINVAL; 504 } 505 return bits_to_user(bits, len, _IOC_SIZE(cmd), p, compat_mode); 506 } 507 508 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0))) 509 return bits_to_user(dev->key, KEY_MAX, _IOC_SIZE(cmd), 510 p, compat_mode); 511 512 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0))) 513 return bits_to_user(dev->led, LED_MAX, _IOC_SIZE(cmd), 514 p, compat_mode); 515 516 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0))) 517 return bits_to_user(dev->snd, SND_MAX, _IOC_SIZE(cmd), 518 p, compat_mode); 519 520 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSW(0))) 521 return bits_to_user(dev->sw, SW_MAX, _IOC_SIZE(cmd), 522 p, compat_mode); 523 524 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) 525 return str_to_user(dev->name, _IOC_SIZE(cmd), p); 526 527 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) 528 return str_to_user(dev->phys, _IOC_SIZE(cmd), p); 529 530 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) 531 return str_to_user(dev->uniq, _IOC_SIZE(cmd), p); 532 533 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) { 534 535 int t = _IOC_NR(cmd) & ABS_MAX; 536 537 abs.value = dev->abs[t]; 538 abs.minimum = dev->absmin[t]; 539 abs.maximum = dev->absmax[t]; 540 abs.fuzz = dev->absfuzz[t]; 541 abs.flat = dev->absflat[t]; 542 543 if (copy_to_user(p, &abs, sizeof(struct input_absinfo))) 544 return -EFAULT; 545 546 return 0; 547 } 548 549 } 550 551 if (_IOC_DIR(cmd) == _IOC_WRITE) { 552 553 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) { 554 555 int t = _IOC_NR(cmd) & ABS_MAX; 556 557 if (copy_from_user(&abs, p, sizeof(struct input_absinfo))) 558 return -EFAULT; 559 560 dev->abs[t] = abs.value; 561 dev->absmin[t] = abs.minimum; 562 dev->absmax[t] = abs.maximum; 563 dev->absfuzz[t] = abs.fuzz; 564 dev->absflat[t] = abs.flat; 565 566 return 0; 567 } 568 } 569 } 570 return -EINVAL; 571 } 572 573 static long evdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 574 { 575 return evdev_ioctl_handler(file, cmd, (void __user *)arg, 0); 576 } 577 578 #ifdef CONFIG_COMPAT 579 static long evdev_ioctl_compat(struct file *file, unsigned int cmd, unsigned long arg) 580 { 581 return evdev_ioctl_handler(file, cmd, compat_ptr(arg), 1); 582 } 583 #endif 584 585 static struct file_operations evdev_fops = { 586 .owner = THIS_MODULE, 587 .read = evdev_read, 588 .write = evdev_write, 589 .poll = evdev_poll, 590 .open = evdev_open, 591 .release = evdev_release, 592 .unlocked_ioctl = evdev_ioctl, 593 #ifdef CONFIG_COMPAT 594 .compat_ioctl = evdev_ioctl_compat, 595 #endif 596 .fasync = evdev_fasync, 597 .flush = evdev_flush 598 }; 599 600 static struct input_handle *evdev_connect(struct input_handler *handler, struct input_dev *dev, struct input_device_id *id) 601 { 602 struct evdev *evdev; 603 struct class_device *cdev; 604 int minor; 605 606 for (minor = 0; minor < EVDEV_MINORS && evdev_table[minor]; minor++); 607 if (minor == EVDEV_MINORS) { 608 printk(KERN_ERR "evdev: no more free evdev devices\n"); 609 return NULL; 610 } 611 612 if (!(evdev = kmalloc(sizeof(struct evdev), GFP_KERNEL))) 613 return NULL; 614 memset(evdev, 0, sizeof(struct evdev)); 615 616 INIT_LIST_HEAD(&evdev->list); 617 init_waitqueue_head(&evdev->wait); 618 619 evdev->exist = 1; 620 evdev->minor = minor; 621 evdev->handle.dev = dev; 622 evdev->handle.name = evdev->name; 623 evdev->handle.handler = handler; 624 evdev->handle.private = evdev; 625 sprintf(evdev->name, "event%d", minor); 626 627 evdev_table[minor] = evdev; 628 629 cdev = class_device_create(&input_class, &dev->cdev, 630 MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor), 631 dev->cdev.dev, evdev->name); 632 633 /* temporary symlink to keep userspace happy */ 634 sysfs_create_link(&input_class.subsys.kset.kobj, &cdev->kobj, 635 evdev->name); 636 637 return &evdev->handle; 638 } 639 640 static void evdev_disconnect(struct input_handle *handle) 641 { 642 struct evdev *evdev = handle->private; 643 struct evdev_list *list; 644 645 sysfs_remove_link(&input_class.subsys.kset.kobj, evdev->name); 646 class_device_destroy(&input_class, 647 MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + evdev->minor)); 648 evdev->exist = 0; 649 650 if (evdev->open) { 651 input_close_device(handle); 652 wake_up_interruptible(&evdev->wait); 653 list_for_each_entry(list, &evdev->list, node) 654 kill_fasync(&list->fasync, SIGIO, POLL_HUP); 655 } else 656 evdev_free(evdev); 657 } 658 659 static struct input_device_id evdev_ids[] = { 660 { .driver_info = 1 }, /* Matches all devices */ 661 { }, /* Terminating zero entry */ 662 }; 663 664 MODULE_DEVICE_TABLE(input, evdev_ids); 665 666 static struct input_handler evdev_handler = { 667 .event = evdev_event, 668 .connect = evdev_connect, 669 .disconnect = evdev_disconnect, 670 .fops = &evdev_fops, 671 .minor = EVDEV_MINOR_BASE, 672 .name = "evdev", 673 .id_table = evdev_ids, 674 }; 675 676 static int __init evdev_init(void) 677 { 678 input_register_handler(&evdev_handler); 679 return 0; 680 } 681 682 static void __exit evdev_exit(void) 683 { 684 input_unregister_handler(&evdev_handler); 685 } 686 687 module_init(evdev_init); 688 module_exit(evdev_exit); 689 690 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); 691 MODULE_DESCRIPTION("Input driver event char devices"); 692 MODULE_LICENSE("GPL"); 693