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/devfs_fs_kernel.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 static ssize_t evdev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos) 149 { 150 struct evdev_list *list = file->private_data; 151 struct input_event event; 152 int retval = 0; 153 154 if (!list->evdev->exist) return -ENODEV; 155 156 while (retval < count) { 157 158 if (copy_from_user(&event, buffer + retval, sizeof(struct input_event))) 159 return -EFAULT; 160 input_event(list->evdev->handle.dev, event.type, event.code, event.value); 161 retval += sizeof(struct input_event); 162 } 163 164 return retval; 165 } 166 167 static ssize_t evdev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos) 168 { 169 struct evdev_list *list = file->private_data; 170 int retval; 171 172 if (count < sizeof(struct input_event)) 173 return -EINVAL; 174 175 if (list->head == list->tail && list->evdev->exist && (file->f_flags & O_NONBLOCK)) 176 return -EAGAIN; 177 178 retval = wait_event_interruptible(list->evdev->wait, 179 list->head != list->tail || (!list->evdev->exist)); 180 181 if (retval) 182 return retval; 183 184 if (!list->evdev->exist) 185 return -ENODEV; 186 187 while (list->head != list->tail && retval + sizeof(struct input_event) <= count) { 188 if (copy_to_user(buffer + retval, list->buffer + list->tail, 189 sizeof(struct input_event))) return -EFAULT; 190 list->tail = (list->tail + 1) & (EVDEV_BUFFER_SIZE - 1); 191 retval += sizeof(struct input_event); 192 } 193 194 return retval; 195 } 196 197 /* No kernel lock - fine */ 198 static unsigned int evdev_poll(struct file *file, poll_table *wait) 199 { 200 struct evdev_list *list = file->private_data; 201 poll_wait(file, &list->evdev->wait, wait); 202 return ((list->head == list->tail) ? 0 : (POLLIN | POLLRDNORM)) | 203 (list->evdev->exist ? 0 : (POLLHUP | POLLERR)); 204 } 205 206 static int evdev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) 207 { 208 struct evdev_list *list = file->private_data; 209 struct evdev *evdev = list->evdev; 210 struct input_dev *dev = evdev->handle.dev; 211 struct input_absinfo abs; 212 void __user *p = (void __user *)arg; 213 int __user *ip = (int __user *)arg; 214 int i, t, u, v; 215 216 if (!evdev->exist) return -ENODEV; 217 218 switch (cmd) { 219 220 case EVIOCGVERSION: 221 return put_user(EV_VERSION, ip); 222 223 case EVIOCGID: 224 return copy_to_user(p, &dev->id, sizeof(struct input_id)) ? -EFAULT : 0; 225 226 case EVIOCGKEYCODE: 227 if (get_user(t, ip)) return -EFAULT; 228 if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) return -EINVAL; 229 if (put_user(INPUT_KEYCODE(dev, t), ip + 1)) return -EFAULT; 230 return 0; 231 232 case EVIOCSKEYCODE: 233 if (get_user(t, ip)) return -EFAULT; 234 if (t < 0 || t >= dev->keycodemax || !dev->keycodesize) return -EINVAL; 235 if (get_user(v, ip + 1)) return -EFAULT; 236 if (v < 0 || v > KEY_MAX) return -EINVAL; 237 u = SET_INPUT_KEYCODE(dev, t, v); 238 clear_bit(u, dev->keybit); 239 set_bit(v, dev->keybit); 240 for (i = 0; i < dev->keycodemax; i++) 241 if (INPUT_KEYCODE(dev,i) == u) 242 set_bit(u, dev->keybit); 243 return 0; 244 245 case EVIOCSFF: 246 if (dev->upload_effect) { 247 struct ff_effect effect; 248 int err; 249 250 if (copy_from_user(&effect, p, sizeof(effect))) 251 return -EFAULT; 252 err = dev->upload_effect(dev, &effect); 253 if (put_user(effect.id, &(((struct ff_effect __user *)arg)->id))) 254 return -EFAULT; 255 return err; 256 } 257 else return -ENOSYS; 258 259 case EVIOCRMFF: 260 if (dev->erase_effect) { 261 return dev->erase_effect(dev, (int)arg); 262 } 263 else return -ENOSYS; 264 265 case EVIOCGEFFECTS: 266 if (put_user(dev->ff_effects_max, ip)) 267 return -EFAULT; 268 return 0; 269 270 case EVIOCGRAB: 271 if (arg) { 272 if (evdev->grab) 273 return -EBUSY; 274 if (input_grab_device(&evdev->handle)) 275 return -EBUSY; 276 evdev->grab = list; 277 return 0; 278 } else { 279 if (evdev->grab != list) 280 return -EINVAL; 281 input_release_device(&evdev->handle); 282 evdev->grab = NULL; 283 return 0; 284 } 285 286 default: 287 288 if (_IOC_TYPE(cmd) != 'E' || _IOC_DIR(cmd) != _IOC_READ) 289 return -EINVAL; 290 291 if ((_IOC_NR(cmd) & ~EV_MAX) == _IOC_NR(EVIOCGBIT(0,0))) { 292 293 long *bits; 294 int len; 295 296 switch (_IOC_NR(cmd) & EV_MAX) { 297 case 0: bits = dev->evbit; len = EV_MAX; break; 298 case EV_KEY: bits = dev->keybit; len = KEY_MAX; break; 299 case EV_REL: bits = dev->relbit; len = REL_MAX; break; 300 case EV_ABS: bits = dev->absbit; len = ABS_MAX; break; 301 case EV_MSC: bits = dev->mscbit; len = MSC_MAX; break; 302 case EV_LED: bits = dev->ledbit; len = LED_MAX; break; 303 case EV_SND: bits = dev->sndbit; len = SND_MAX; break; 304 case EV_FF: bits = dev->ffbit; len = FF_MAX; break; 305 default: return -EINVAL; 306 } 307 len = NBITS(len) * sizeof(long); 308 if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd); 309 return copy_to_user(p, bits, len) ? -EFAULT : len; 310 } 311 312 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGKEY(0))) { 313 int len; 314 len = NBITS(KEY_MAX) * sizeof(long); 315 if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd); 316 return copy_to_user(p, dev->key, len) ? -EFAULT : len; 317 } 318 319 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGLED(0))) { 320 int len; 321 len = NBITS(LED_MAX) * sizeof(long); 322 if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd); 323 return copy_to_user(p, dev->led, len) ? -EFAULT : len; 324 } 325 326 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGSND(0))) { 327 int len; 328 len = NBITS(SND_MAX) * sizeof(long); 329 if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd); 330 return copy_to_user(p, dev->snd, len) ? -EFAULT : len; 331 } 332 333 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGNAME(0))) { 334 int len; 335 if (!dev->name) return -ENOENT; 336 len = strlen(dev->name) + 1; 337 if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd); 338 return copy_to_user(p, dev->name, len) ? -EFAULT : len; 339 } 340 341 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGPHYS(0))) { 342 int len; 343 if (!dev->phys) return -ENOENT; 344 len = strlen(dev->phys) + 1; 345 if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd); 346 return copy_to_user(p, dev->phys, len) ? -EFAULT : len; 347 } 348 349 if (_IOC_NR(cmd) == _IOC_NR(EVIOCGUNIQ(0))) { 350 int len; 351 if (!dev->uniq) return -ENOENT; 352 len = strlen(dev->uniq) + 1; 353 if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd); 354 return copy_to_user(p, dev->uniq, len) ? -EFAULT : len; 355 } 356 357 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCGABS(0))) { 358 359 int t = _IOC_NR(cmd) & ABS_MAX; 360 361 abs.value = dev->abs[t]; 362 abs.minimum = dev->absmin[t]; 363 abs.maximum = dev->absmax[t]; 364 abs.fuzz = dev->absfuzz[t]; 365 abs.flat = dev->absflat[t]; 366 367 if (copy_to_user(p, &abs, sizeof(struct input_absinfo))) 368 return -EFAULT; 369 370 return 0; 371 } 372 373 if ((_IOC_NR(cmd) & ~ABS_MAX) == _IOC_NR(EVIOCSABS(0))) { 374 375 int t = _IOC_NR(cmd) & ABS_MAX; 376 377 if (copy_from_user(&abs, p, sizeof(struct input_absinfo))) 378 return -EFAULT; 379 380 dev->abs[t] = abs.value; 381 dev->absmin[t] = abs.minimum; 382 dev->absmax[t] = abs.maximum; 383 dev->absfuzz[t] = abs.fuzz; 384 dev->absflat[t] = abs.flat; 385 386 return 0; 387 } 388 } 389 return -EINVAL; 390 } 391 392 static struct file_operations evdev_fops = { 393 .owner = THIS_MODULE, 394 .read = evdev_read, 395 .write = evdev_write, 396 .poll = evdev_poll, 397 .open = evdev_open, 398 .release = evdev_release, 399 .ioctl = evdev_ioctl, 400 .fasync = evdev_fasync, 401 .flush = evdev_flush 402 }; 403 404 static struct input_handle *evdev_connect(struct input_handler *handler, struct input_dev *dev, struct input_device_id *id) 405 { 406 struct evdev *evdev; 407 int minor; 408 409 for (minor = 0; minor < EVDEV_MINORS && evdev_table[minor]; minor++); 410 if (minor == EVDEV_MINORS) { 411 printk(KERN_ERR "evdev: no more free evdev devices\n"); 412 return NULL; 413 } 414 415 if (!(evdev = kmalloc(sizeof(struct evdev), GFP_KERNEL))) 416 return NULL; 417 memset(evdev, 0, sizeof(struct evdev)); 418 419 INIT_LIST_HEAD(&evdev->list); 420 init_waitqueue_head(&evdev->wait); 421 422 evdev->exist = 1; 423 evdev->minor = minor; 424 evdev->handle.dev = dev; 425 evdev->handle.name = evdev->name; 426 evdev->handle.handler = handler; 427 evdev->handle.private = evdev; 428 sprintf(evdev->name, "event%d", minor); 429 430 evdev_table[minor] = evdev; 431 432 devfs_mk_cdev(MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor), 433 S_IFCHR|S_IRUGO|S_IWUSR, "input/event%d", minor); 434 class_simple_device_add(input_class, 435 MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + minor), 436 dev->dev, "event%d", minor); 437 438 return &evdev->handle; 439 } 440 441 static void evdev_disconnect(struct input_handle *handle) 442 { 443 struct evdev *evdev = handle->private; 444 struct evdev_list *list; 445 446 class_simple_device_remove(MKDEV(INPUT_MAJOR, EVDEV_MINOR_BASE + evdev->minor)); 447 devfs_remove("input/event%d", evdev->minor); 448 evdev->exist = 0; 449 450 if (evdev->open) { 451 input_close_device(handle); 452 wake_up_interruptible(&evdev->wait); 453 list_for_each_entry(list, &evdev->list, node) 454 kill_fasync(&list->fasync, SIGIO, POLL_HUP); 455 } else 456 evdev_free(evdev); 457 } 458 459 static struct input_device_id evdev_ids[] = { 460 { .driver_info = 1 }, /* Matches all devices */ 461 { }, /* Terminating zero entry */ 462 }; 463 464 MODULE_DEVICE_TABLE(input, evdev_ids); 465 466 static struct input_handler evdev_handler = { 467 .event = evdev_event, 468 .connect = evdev_connect, 469 .disconnect = evdev_disconnect, 470 .fops = &evdev_fops, 471 .minor = EVDEV_MINOR_BASE, 472 .name = "evdev", 473 .id_table = evdev_ids, 474 }; 475 476 static int __init evdev_init(void) 477 { 478 input_register_handler(&evdev_handler); 479 return 0; 480 } 481 482 static void __exit evdev_exit(void) 483 { 484 input_unregister_handler(&evdev_handler); 485 } 486 487 module_init(evdev_init); 488 module_exit(evdev_exit); 489 490 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); 491 MODULE_DESCRIPTION("Input driver event char devices"); 492 MODULE_LICENSE("GPL"); 493