1 /* 2 * User level driver support for input subsystem 3 * 4 * Heavily based on evdev.c by Vojtech Pavlik 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19 * 20 * Author: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org> 21 * 22 * Changes/Revisions: 23 * 0.3 09/04/2006 (Anssi Hannula <anssi.hannula@gmail.com>) 24 * - updated ff support for the changes in kernel interface 25 * - added MODULE_VERSION 26 * 0.2 16/10/2004 (Micah Dowty <micah@navi.cx>) 27 * - added force feedback support 28 * - added UI_SET_PHYS 29 * 0.1 20/06/2002 30 * - first public version 31 */ 32 #include <linux/poll.h> 33 #include <linux/slab.h> 34 #include <linux/module.h> 35 #include <linux/init.h> 36 #include <linux/input.h> 37 #include <linux/smp_lock.h> 38 #include <linux/fs.h> 39 #include <linux/miscdevice.h> 40 #include <linux/uinput.h> 41 42 static int uinput_dev_event(struct input_dev *dev, unsigned int type, unsigned int code, int value) 43 { 44 struct uinput_device *udev = input_get_drvdata(dev); 45 46 udev->buff[udev->head].type = type; 47 udev->buff[udev->head].code = code; 48 udev->buff[udev->head].value = value; 49 do_gettimeofday(&udev->buff[udev->head].time); 50 udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE; 51 52 wake_up_interruptible(&udev->waitq); 53 54 return 0; 55 } 56 57 static int uinput_request_alloc_id(struct uinput_device *udev, struct uinput_request *request) 58 { 59 /* Atomically allocate an ID for the given request. Returns 0 on success. */ 60 int id; 61 int err = -1; 62 63 spin_lock(&udev->requests_lock); 64 65 for (id = 0; id < UINPUT_NUM_REQUESTS; id++) 66 if (!udev->requests[id]) { 67 request->id = id; 68 udev->requests[id] = request; 69 err = 0; 70 break; 71 } 72 73 spin_unlock(&udev->requests_lock); 74 return err; 75 } 76 77 static struct uinput_request* uinput_request_find(struct uinput_device *udev, int id) 78 { 79 /* Find an input request, by ID. Returns NULL if the ID isn't valid. */ 80 if (id >= UINPUT_NUM_REQUESTS || id < 0) 81 return NULL; 82 return udev->requests[id]; 83 } 84 85 static inline int uinput_request_reserve_slot(struct uinput_device *udev, struct uinput_request *request) 86 { 87 /* Allocate slot. If none are available right away, wait. */ 88 return wait_event_interruptible(udev->requests_waitq, 89 !uinput_request_alloc_id(udev, request)); 90 } 91 92 static void uinput_request_done(struct uinput_device *udev, struct uinput_request *request) 93 { 94 /* Mark slot as available */ 95 udev->requests[request->id] = NULL; 96 wake_up(&udev->requests_waitq); 97 98 complete(&request->done); 99 } 100 101 static int uinput_request_submit(struct input_dev *dev, struct uinput_request *request) 102 { 103 /* Tell our userspace app about this new request by queueing an input event */ 104 uinput_dev_event(dev, EV_UINPUT, request->code, request->id); 105 106 /* Wait for the request to complete */ 107 wait_for_completion(&request->done); 108 return request->retval; 109 } 110 111 static void uinput_dev_set_gain(struct input_dev *dev, u16 gain) 112 { 113 uinput_dev_event(dev, EV_FF, FF_GAIN, gain); 114 } 115 116 static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude) 117 { 118 uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude); 119 } 120 121 static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value) 122 { 123 return uinput_dev_event(dev, EV_FF, effect_id, value); 124 } 125 126 static int uinput_dev_upload_effect(struct input_dev *dev, struct ff_effect *effect, struct ff_effect *old) 127 { 128 struct uinput_request request; 129 int retval; 130 131 request.id = -1; 132 init_completion(&request.done); 133 request.code = UI_FF_UPLOAD; 134 request.u.upload.effect = effect; 135 request.u.upload.old = old; 136 137 retval = uinput_request_reserve_slot(input_get_drvdata(dev), &request); 138 if (!retval) 139 retval = uinput_request_submit(dev, &request); 140 141 return retval; 142 } 143 144 static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id) 145 { 146 struct uinput_request request; 147 int retval; 148 149 if (!test_bit(EV_FF, dev->evbit)) 150 return -ENOSYS; 151 152 request.id = -1; 153 init_completion(&request.done); 154 request.code = UI_FF_ERASE; 155 request.u.effect_id = effect_id; 156 157 retval = uinput_request_reserve_slot(input_get_drvdata(dev), &request); 158 if (!retval) 159 retval = uinput_request_submit(dev, &request); 160 161 return retval; 162 } 163 164 static void uinput_destroy_device(struct uinput_device *udev) 165 { 166 const char *name, *phys; 167 168 if (udev->dev) { 169 name = udev->dev->name; 170 phys = udev->dev->phys; 171 if (udev->state == UIST_CREATED) 172 input_unregister_device(udev->dev); 173 else 174 input_free_device(udev->dev); 175 kfree(name); 176 kfree(phys); 177 udev->dev = NULL; 178 } 179 180 udev->state = UIST_NEW_DEVICE; 181 } 182 183 static int uinput_create_device(struct uinput_device *udev) 184 { 185 struct input_dev *dev = udev->dev; 186 int error; 187 188 if (udev->state != UIST_SETUP_COMPLETE) { 189 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME); 190 return -EINVAL; 191 } 192 193 if (udev->ff_effects_max) { 194 error = input_ff_create(dev, udev->ff_effects_max); 195 if (error) 196 goto fail1; 197 198 dev->ff->upload = uinput_dev_upload_effect; 199 dev->ff->erase = uinput_dev_erase_effect; 200 dev->ff->playback = uinput_dev_playback; 201 dev->ff->set_gain = uinput_dev_set_gain; 202 dev->ff->set_autocenter = uinput_dev_set_autocenter; 203 } 204 205 error = input_register_device(udev->dev); 206 if (error) 207 goto fail2; 208 209 udev->state = UIST_CREATED; 210 211 return 0; 212 213 fail2: input_ff_destroy(dev); 214 fail1: uinput_destroy_device(udev); 215 return error; 216 } 217 218 static int uinput_open(struct inode *inode, struct file *file) 219 { 220 struct uinput_device *newdev; 221 222 newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL); 223 if (!newdev) 224 return -ENOMEM; 225 226 mutex_init(&newdev->mutex); 227 spin_lock_init(&newdev->requests_lock); 228 init_waitqueue_head(&newdev->requests_waitq); 229 init_waitqueue_head(&newdev->waitq); 230 newdev->state = UIST_NEW_DEVICE; 231 232 file->private_data = newdev; 233 234 return 0; 235 } 236 237 static int uinput_validate_absbits(struct input_dev *dev) 238 { 239 unsigned int cnt; 240 int retval = 0; 241 242 for (cnt = 0; cnt < ABS_MAX + 1; cnt++) { 243 if (!test_bit(cnt, dev->absbit)) 244 continue; 245 246 if ((dev->absmax[cnt] <= dev->absmin[cnt])) { 247 printk(KERN_DEBUG 248 "%s: invalid abs[%02x] min:%d max:%d\n", 249 UINPUT_NAME, cnt, 250 dev->absmin[cnt], dev->absmax[cnt]); 251 retval = -EINVAL; 252 break; 253 } 254 255 if (dev->absflat[cnt] > (dev->absmax[cnt] - dev->absmin[cnt])) { 256 printk(KERN_DEBUG 257 "%s: absflat[%02x] out of range: %d " 258 "(min:%d/max:%d)\n", 259 UINPUT_NAME, cnt, dev->absflat[cnt], 260 dev->absmin[cnt], dev->absmax[cnt]); 261 retval = -EINVAL; 262 break; 263 } 264 } 265 return retval; 266 } 267 268 static int uinput_allocate_device(struct uinput_device *udev) 269 { 270 udev->dev = input_allocate_device(); 271 if (!udev->dev) 272 return -ENOMEM; 273 274 udev->dev->event = uinput_dev_event; 275 input_set_drvdata(udev->dev, udev); 276 277 return 0; 278 } 279 280 static int uinput_setup_device(struct uinput_device *udev, const char __user *buffer, size_t count) 281 { 282 struct uinput_user_dev *user_dev; 283 struct input_dev *dev; 284 char *name; 285 int size; 286 int retval; 287 288 if (count != sizeof(struct uinput_user_dev)) 289 return -EINVAL; 290 291 if (!udev->dev) { 292 retval = uinput_allocate_device(udev); 293 if (retval) 294 return retval; 295 } 296 297 dev = udev->dev; 298 299 user_dev = kmalloc(sizeof(struct uinput_user_dev), GFP_KERNEL); 300 if (!user_dev) 301 return -ENOMEM; 302 303 if (copy_from_user(user_dev, buffer, sizeof(struct uinput_user_dev))) { 304 retval = -EFAULT; 305 goto exit; 306 } 307 308 udev->ff_effects_max = user_dev->ff_effects_max; 309 310 size = strnlen(user_dev->name, UINPUT_MAX_NAME_SIZE) + 1; 311 if (!size) { 312 retval = -EINVAL; 313 goto exit; 314 } 315 316 kfree(dev->name); 317 dev->name = name = kmalloc(size, GFP_KERNEL); 318 if (!name) { 319 retval = -ENOMEM; 320 goto exit; 321 } 322 strlcpy(name, user_dev->name, size); 323 324 dev->id.bustype = user_dev->id.bustype; 325 dev->id.vendor = user_dev->id.vendor; 326 dev->id.product = user_dev->id.product; 327 dev->id.version = user_dev->id.version; 328 329 size = sizeof(int) * (ABS_MAX + 1); 330 memcpy(dev->absmax, user_dev->absmax, size); 331 memcpy(dev->absmin, user_dev->absmin, size); 332 memcpy(dev->absfuzz, user_dev->absfuzz, size); 333 memcpy(dev->absflat, user_dev->absflat, size); 334 335 /* check if absmin/absmax/absfuzz/absflat are filled as 336 * told in Documentation/input/input-programming.txt */ 337 if (test_bit(EV_ABS, dev->evbit)) { 338 retval = uinput_validate_absbits(dev); 339 if (retval < 0) 340 goto exit; 341 } 342 343 udev->state = UIST_SETUP_COMPLETE; 344 retval = count; 345 346 exit: 347 kfree(user_dev); 348 return retval; 349 } 350 351 static inline ssize_t uinput_inject_event(struct uinput_device *udev, const char __user *buffer, size_t count) 352 { 353 struct input_event ev; 354 355 if (count != sizeof(struct input_event)) 356 return -EINVAL; 357 358 if (copy_from_user(&ev, buffer, sizeof(struct input_event))) 359 return -EFAULT; 360 361 input_event(udev->dev, ev.type, ev.code, ev.value); 362 363 return sizeof(struct input_event); 364 } 365 366 static ssize_t uinput_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) 367 { 368 struct uinput_device *udev = file->private_data; 369 int retval; 370 371 retval = mutex_lock_interruptible(&udev->mutex); 372 if (retval) 373 return retval; 374 375 retval = udev->state == UIST_CREATED ? 376 uinput_inject_event(udev, buffer, count) : 377 uinput_setup_device(udev, buffer, count); 378 379 mutex_unlock(&udev->mutex); 380 381 return retval; 382 } 383 384 static ssize_t uinput_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos) 385 { 386 struct uinput_device *udev = file->private_data; 387 int retval = 0; 388 389 if (udev->state != UIST_CREATED) 390 return -ENODEV; 391 392 if (udev->head == udev->tail && (file->f_flags & O_NONBLOCK)) 393 return -EAGAIN; 394 395 retval = wait_event_interruptible(udev->waitq, 396 udev->head != udev->tail || udev->state != UIST_CREATED); 397 if (retval) 398 return retval; 399 400 retval = mutex_lock_interruptible(&udev->mutex); 401 if (retval) 402 return retval; 403 404 if (udev->state != UIST_CREATED) { 405 retval = -ENODEV; 406 goto out; 407 } 408 409 while (udev->head != udev->tail && retval + sizeof(struct input_event) <= count) { 410 if (copy_to_user(buffer + retval, &udev->buff[udev->tail], sizeof(struct input_event))) { 411 retval = -EFAULT; 412 goto out; 413 } 414 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE; 415 retval += sizeof(struct input_event); 416 } 417 418 out: 419 mutex_unlock(&udev->mutex); 420 421 return retval; 422 } 423 424 static unsigned int uinput_poll(struct file *file, poll_table *wait) 425 { 426 struct uinput_device *udev = file->private_data; 427 428 poll_wait(file, &udev->waitq, wait); 429 430 if (udev->head != udev->tail) 431 return POLLIN | POLLRDNORM; 432 433 return 0; 434 } 435 436 static int uinput_release(struct inode *inode, struct file *file) 437 { 438 struct uinput_device *udev = file->private_data; 439 440 uinput_destroy_device(udev); 441 kfree(udev); 442 443 return 0; 444 } 445 446 #define uinput_set_bit(_arg, _bit, _max) \ 447 ({ \ 448 int __ret = 0; \ 449 if (udev->state == UIST_CREATED) \ 450 __ret = -EINVAL; \ 451 else if ((_arg) > (_max)) \ 452 __ret = -EINVAL; \ 453 else set_bit((_arg), udev->dev->_bit); \ 454 __ret; \ 455 }) 456 457 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 458 { 459 int retval; 460 struct uinput_device *udev; 461 void __user *p = (void __user *)arg; 462 struct uinput_ff_upload ff_up; 463 struct uinput_ff_erase ff_erase; 464 struct uinput_request *req; 465 int length; 466 char *phys; 467 468 udev = file->private_data; 469 470 retval = mutex_lock_interruptible(&udev->mutex); 471 if (retval) 472 return retval; 473 474 if (!udev->dev) { 475 retval = uinput_allocate_device(udev); 476 if (retval) 477 goto out; 478 } 479 480 switch (cmd) { 481 case UI_DEV_CREATE: 482 retval = uinput_create_device(udev); 483 break; 484 485 case UI_DEV_DESTROY: 486 uinput_destroy_device(udev); 487 break; 488 489 case UI_SET_EVBIT: 490 retval = uinput_set_bit(arg, evbit, EV_MAX); 491 break; 492 493 case UI_SET_KEYBIT: 494 retval = uinput_set_bit(arg, keybit, KEY_MAX); 495 break; 496 497 case UI_SET_RELBIT: 498 retval = uinput_set_bit(arg, relbit, REL_MAX); 499 break; 500 501 case UI_SET_ABSBIT: 502 retval = uinput_set_bit(arg, absbit, ABS_MAX); 503 break; 504 505 case UI_SET_MSCBIT: 506 retval = uinput_set_bit(arg, mscbit, MSC_MAX); 507 break; 508 509 case UI_SET_LEDBIT: 510 retval = uinput_set_bit(arg, ledbit, LED_MAX); 511 break; 512 513 case UI_SET_SNDBIT: 514 retval = uinput_set_bit(arg, sndbit, SND_MAX); 515 break; 516 517 case UI_SET_FFBIT: 518 retval = uinput_set_bit(arg, ffbit, FF_MAX); 519 break; 520 521 case UI_SET_SWBIT: 522 retval = uinput_set_bit(arg, swbit, SW_MAX); 523 break; 524 525 case UI_SET_PHYS: 526 if (udev->state == UIST_CREATED) { 527 retval = -EINVAL; 528 goto out; 529 } 530 length = strnlen_user(p, 1024); 531 if (length <= 0) { 532 retval = -EFAULT; 533 break; 534 } 535 kfree(udev->dev->phys); 536 udev->dev->phys = phys = kmalloc(length, GFP_KERNEL); 537 if (!phys) { 538 retval = -ENOMEM; 539 break; 540 } 541 if (copy_from_user(phys, p, length)) { 542 udev->dev->phys = NULL; 543 kfree(phys); 544 retval = -EFAULT; 545 break; 546 } 547 phys[length - 1] = '\0'; 548 break; 549 550 case UI_BEGIN_FF_UPLOAD: 551 if (copy_from_user(&ff_up, p, sizeof(ff_up))) { 552 retval = -EFAULT; 553 break; 554 } 555 req = uinput_request_find(udev, ff_up.request_id); 556 if (!(req && req->code == UI_FF_UPLOAD && req->u.upload.effect)) { 557 retval = -EINVAL; 558 break; 559 } 560 ff_up.retval = 0; 561 memcpy(&ff_up.effect, req->u.upload.effect, sizeof(struct ff_effect)); 562 if (req->u.upload.old) 563 memcpy(&ff_up.old, req->u.upload.old, sizeof(struct ff_effect)); 564 else 565 memset(&ff_up.old, 0, sizeof(struct ff_effect)); 566 567 if (copy_to_user(p, &ff_up, sizeof(ff_up))) { 568 retval = -EFAULT; 569 break; 570 } 571 break; 572 573 case UI_BEGIN_FF_ERASE: 574 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 575 retval = -EFAULT; 576 break; 577 } 578 req = uinput_request_find(udev, ff_erase.request_id); 579 if (!(req && req->code == UI_FF_ERASE)) { 580 retval = -EINVAL; 581 break; 582 } 583 ff_erase.retval = 0; 584 ff_erase.effect_id = req->u.effect_id; 585 if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) { 586 retval = -EFAULT; 587 break; 588 } 589 break; 590 591 case UI_END_FF_UPLOAD: 592 if (copy_from_user(&ff_up, p, sizeof(ff_up))) { 593 retval = -EFAULT; 594 break; 595 } 596 req = uinput_request_find(udev, ff_up.request_id); 597 if (!(req && req->code == UI_FF_UPLOAD && req->u.upload.effect)) { 598 retval = -EINVAL; 599 break; 600 } 601 req->retval = ff_up.retval; 602 uinput_request_done(udev, req); 603 break; 604 605 case UI_END_FF_ERASE: 606 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 607 retval = -EFAULT; 608 break; 609 } 610 req = uinput_request_find(udev, ff_erase.request_id); 611 if (!(req && req->code == UI_FF_ERASE)) { 612 retval = -EINVAL; 613 break; 614 } 615 req->retval = ff_erase.retval; 616 uinput_request_done(udev, req); 617 break; 618 619 default: 620 retval = -EINVAL; 621 } 622 623 out: 624 mutex_unlock(&udev->mutex); 625 return retval; 626 } 627 628 static const struct file_operations uinput_fops = { 629 .owner = THIS_MODULE, 630 .open = uinput_open, 631 .release = uinput_release, 632 .read = uinput_read, 633 .write = uinput_write, 634 .poll = uinput_poll, 635 .unlocked_ioctl = uinput_ioctl, 636 }; 637 638 static struct miscdevice uinput_misc = { 639 .fops = &uinput_fops, 640 .minor = UINPUT_MINOR, 641 .name = UINPUT_NAME, 642 }; 643 644 static int __init uinput_init(void) 645 { 646 return misc_register(&uinput_misc); 647 } 648 649 static void __exit uinput_exit(void) 650 { 651 misc_deregister(&uinput_misc); 652 } 653 654 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho"); 655 MODULE_DESCRIPTION("User level driver support for input subsystem"); 656 MODULE_LICENSE("GPL"); 657 MODULE_VERSION("0.3"); 658 659 module_init(uinput_init); 660 module_exit(uinput_exit); 661 662