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/smp_lock.h> 37 #include <linux/fs.h> 38 #include <linux/miscdevice.h> 39 #include <linux/uinput.h> 40 41 static int uinput_dev_event(struct input_dev *dev, unsigned int type, unsigned int code, int value) 42 { 43 struct uinput_device *udev = input_get_drvdata(dev); 44 45 udev->buff[udev->head].type = type; 46 udev->buff[udev->head].code = code; 47 udev->buff[udev->head].value = value; 48 do_gettimeofday(&udev->buff[udev->head].time); 49 udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE; 50 51 wake_up_interruptible(&udev->waitq); 52 53 return 0; 54 } 55 56 static int uinput_request_alloc_id(struct uinput_device *udev, struct uinput_request *request) 57 { 58 /* Atomically allocate an ID for the given request. Returns 0 on success. */ 59 int id; 60 int err = -1; 61 62 spin_lock(&udev->requests_lock); 63 64 for (id = 0; id < UINPUT_NUM_REQUESTS; id++) 65 if (!udev->requests[id]) { 66 request->id = id; 67 udev->requests[id] = request; 68 err = 0; 69 break; 70 } 71 72 spin_unlock(&udev->requests_lock); 73 return err; 74 } 75 76 static struct uinput_request* uinput_request_find(struct uinput_device *udev, int id) 77 { 78 /* Find an input request, by ID. Returns NULL if the ID isn't valid. */ 79 if (id >= UINPUT_NUM_REQUESTS || id < 0) 80 return NULL; 81 return udev->requests[id]; 82 } 83 84 static inline int uinput_request_reserve_slot(struct uinput_device *udev, struct uinput_request *request) 85 { 86 /* Allocate slot. If none are available right away, wait. */ 87 return wait_event_interruptible(udev->requests_waitq, 88 !uinput_request_alloc_id(udev, request)); 89 } 90 91 static void uinput_request_done(struct uinput_device *udev, struct uinput_request *request) 92 { 93 /* Mark slot as available */ 94 udev->requests[request->id] = NULL; 95 wake_up(&udev->requests_waitq); 96 97 complete(&request->done); 98 } 99 100 static int uinput_request_submit(struct input_dev *dev, struct uinput_request *request) 101 { 102 /* Tell our userspace app about this new request by queueing an input event */ 103 uinput_dev_event(dev, EV_UINPUT, request->code, request->id); 104 105 /* Wait for the request to complete */ 106 wait_for_completion(&request->done); 107 return request->retval; 108 } 109 110 static void uinput_dev_set_gain(struct input_dev *dev, u16 gain) 111 { 112 uinput_dev_event(dev, EV_FF, FF_GAIN, gain); 113 } 114 115 static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude) 116 { 117 uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude); 118 } 119 120 static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value) 121 { 122 return uinput_dev_event(dev, EV_FF, effect_id, value); 123 } 124 125 static int uinput_dev_upload_effect(struct input_dev *dev, struct ff_effect *effect, struct ff_effect *old) 126 { 127 struct uinput_request request; 128 int retval; 129 130 request.id = -1; 131 init_completion(&request.done); 132 request.code = UI_FF_UPLOAD; 133 request.u.upload.effect = effect; 134 request.u.upload.old = old; 135 136 retval = uinput_request_reserve_slot(input_get_drvdata(dev), &request); 137 if (!retval) 138 retval = uinput_request_submit(dev, &request); 139 140 return retval; 141 } 142 143 static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id) 144 { 145 struct uinput_request request; 146 int retval; 147 148 if (!test_bit(EV_FF, dev->evbit)) 149 return -ENOSYS; 150 151 request.id = -1; 152 init_completion(&request.done); 153 request.code = UI_FF_ERASE; 154 request.u.effect_id = effect_id; 155 156 retval = uinput_request_reserve_slot(input_get_drvdata(dev), &request); 157 if (!retval) 158 retval = uinput_request_submit(dev, &request); 159 160 return retval; 161 } 162 163 static void uinput_destroy_device(struct uinput_device *udev) 164 { 165 const char *name, *phys; 166 167 if (udev->dev) { 168 name = udev->dev->name; 169 phys = udev->dev->phys; 170 if (udev->state == UIST_CREATED) 171 input_unregister_device(udev->dev); 172 else 173 input_free_device(udev->dev); 174 kfree(name); 175 kfree(phys); 176 udev->dev = NULL; 177 } 178 179 udev->state = UIST_NEW_DEVICE; 180 } 181 182 static int uinput_create_device(struct uinput_device *udev) 183 { 184 struct input_dev *dev = udev->dev; 185 int error; 186 187 if (udev->state != UIST_SETUP_COMPLETE) { 188 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME); 189 return -EINVAL; 190 } 191 192 if (udev->ff_effects_max) { 193 error = input_ff_create(dev, udev->ff_effects_max); 194 if (error) 195 goto fail1; 196 197 dev->ff->upload = uinput_dev_upload_effect; 198 dev->ff->erase = uinput_dev_erase_effect; 199 dev->ff->playback = uinput_dev_playback; 200 dev->ff->set_gain = uinput_dev_set_gain; 201 dev->ff->set_autocenter = uinput_dev_set_autocenter; 202 } 203 204 error = input_register_device(udev->dev); 205 if (error) 206 goto fail2; 207 208 udev->state = UIST_CREATED; 209 210 return 0; 211 212 fail2: input_ff_destroy(dev); 213 fail1: uinput_destroy_device(udev); 214 return error; 215 } 216 217 static int uinput_open(struct inode *inode, struct file *file) 218 { 219 struct uinput_device *newdev; 220 221 newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL); 222 if (!newdev) 223 return -ENOMEM; 224 225 lock_kernel(); 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 unlock_kernel(); 234 235 return 0; 236 } 237 238 static int uinput_validate_absbits(struct input_dev *dev) 239 { 240 unsigned int cnt; 241 int retval = 0; 242 243 for (cnt = 0; cnt < ABS_MAX + 1; cnt++) { 244 if (!test_bit(cnt, dev->absbit)) 245 continue; 246 247 if ((dev->absmax[cnt] <= dev->absmin[cnt])) { 248 printk(KERN_DEBUG 249 "%s: invalid abs[%02x] min:%d max:%d\n", 250 UINPUT_NAME, cnt, 251 dev->absmin[cnt], dev->absmax[cnt]); 252 retval = -EINVAL; 253 break; 254 } 255 256 if (dev->absflat[cnt] > (dev->absmax[cnt] - dev->absmin[cnt])) { 257 printk(KERN_DEBUG 258 "%s: absflat[%02x] out of range: %d " 259 "(min:%d/max:%d)\n", 260 UINPUT_NAME, cnt, dev->absflat[cnt], 261 dev->absmin[cnt], dev->absmax[cnt]); 262 retval = -EINVAL; 263 break; 264 } 265 } 266 return retval; 267 } 268 269 static int uinput_allocate_device(struct uinput_device *udev) 270 { 271 udev->dev = input_allocate_device(); 272 if (!udev->dev) 273 return -ENOMEM; 274 275 udev->dev->event = uinput_dev_event; 276 input_set_drvdata(udev->dev, udev); 277 278 return 0; 279 } 280 281 static int uinput_setup_device(struct uinput_device *udev, const char __user *buffer, size_t count) 282 { 283 struct uinput_user_dev *user_dev; 284 struct input_dev *dev; 285 char *name; 286 int size; 287 int retval; 288 289 if (count != sizeof(struct uinput_user_dev)) 290 return -EINVAL; 291 292 if (!udev->dev) { 293 retval = uinput_allocate_device(udev); 294 if (retval) 295 return retval; 296 } 297 298 dev = udev->dev; 299 300 user_dev = kmalloc(sizeof(struct uinput_user_dev), GFP_KERNEL); 301 if (!user_dev) 302 return -ENOMEM; 303 304 if (copy_from_user(user_dev, buffer, sizeof(struct uinput_user_dev))) { 305 retval = -EFAULT; 306 goto exit; 307 } 308 309 udev->ff_effects_max = user_dev->ff_effects_max; 310 311 size = strnlen(user_dev->name, UINPUT_MAX_NAME_SIZE) + 1; 312 if (!size) { 313 retval = -EINVAL; 314 goto exit; 315 } 316 317 kfree(dev->name); 318 dev->name = name = kmalloc(size, GFP_KERNEL); 319 if (!name) { 320 retval = -ENOMEM; 321 goto exit; 322 } 323 strlcpy(name, user_dev->name, size); 324 325 dev->id.bustype = user_dev->id.bustype; 326 dev->id.vendor = user_dev->id.vendor; 327 dev->id.product = user_dev->id.product; 328 dev->id.version = user_dev->id.version; 329 330 size = sizeof(int) * (ABS_MAX + 1); 331 memcpy(dev->absmax, user_dev->absmax, size); 332 memcpy(dev->absmin, user_dev->absmin, size); 333 memcpy(dev->absfuzz, user_dev->absfuzz, size); 334 memcpy(dev->absflat, user_dev->absflat, size); 335 336 /* check if absmin/absmax/absfuzz/absflat are filled as 337 * told in Documentation/input/input-programming.txt */ 338 if (test_bit(EV_ABS, dev->evbit)) { 339 retval = uinput_validate_absbits(dev); 340 if (retval < 0) 341 goto exit; 342 } 343 344 udev->state = UIST_SETUP_COMPLETE; 345 retval = count; 346 347 exit: 348 kfree(user_dev); 349 return retval; 350 } 351 352 static inline ssize_t uinput_inject_event(struct uinput_device *udev, const char __user *buffer, size_t count) 353 { 354 struct input_event ev; 355 356 if (count != sizeof(struct input_event)) 357 return -EINVAL; 358 359 if (copy_from_user(&ev, buffer, sizeof(struct input_event))) 360 return -EFAULT; 361 362 input_event(udev->dev, ev.type, ev.code, ev.value); 363 364 return sizeof(struct input_event); 365 } 366 367 static ssize_t uinput_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) 368 { 369 struct uinput_device *udev = file->private_data; 370 int retval; 371 372 retval = mutex_lock_interruptible(&udev->mutex); 373 if (retval) 374 return retval; 375 376 retval = udev->state == UIST_CREATED ? 377 uinput_inject_event(udev, buffer, count) : 378 uinput_setup_device(udev, buffer, count); 379 380 mutex_unlock(&udev->mutex); 381 382 return retval; 383 } 384 385 static ssize_t uinput_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos) 386 { 387 struct uinput_device *udev = file->private_data; 388 int retval = 0; 389 390 if (udev->state != UIST_CREATED) 391 return -ENODEV; 392 393 if (udev->head == udev->tail && (file->f_flags & O_NONBLOCK)) 394 return -EAGAIN; 395 396 retval = wait_event_interruptible(udev->waitq, 397 udev->head != udev->tail || udev->state != UIST_CREATED); 398 if (retval) 399 return retval; 400 401 retval = mutex_lock_interruptible(&udev->mutex); 402 if (retval) 403 return retval; 404 405 if (udev->state != UIST_CREATED) { 406 retval = -ENODEV; 407 goto out; 408 } 409 410 while (udev->head != udev->tail && retval + sizeof(struct input_event) <= count) { 411 if (copy_to_user(buffer + retval, &udev->buff[udev->tail], sizeof(struct input_event))) { 412 retval = -EFAULT; 413 goto out; 414 } 415 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE; 416 retval += sizeof(struct input_event); 417 } 418 419 out: 420 mutex_unlock(&udev->mutex); 421 422 return retval; 423 } 424 425 static unsigned int uinput_poll(struct file *file, poll_table *wait) 426 { 427 struct uinput_device *udev = file->private_data; 428 429 poll_wait(file, &udev->waitq, wait); 430 431 if (udev->head != udev->tail) 432 return POLLIN | POLLRDNORM; 433 434 return 0; 435 } 436 437 static int uinput_release(struct inode *inode, struct file *file) 438 { 439 struct uinput_device *udev = file->private_data; 440 441 uinput_destroy_device(udev); 442 kfree(udev); 443 444 return 0; 445 } 446 447 #define uinput_set_bit(_arg, _bit, _max) \ 448 ({ \ 449 int __ret = 0; \ 450 if (udev->state == UIST_CREATED) \ 451 __ret = -EINVAL; \ 452 else if ((_arg) > (_max)) \ 453 __ret = -EINVAL; \ 454 else set_bit((_arg), udev->dev->_bit); \ 455 __ret; \ 456 }) 457 458 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 459 { 460 int retval; 461 struct uinput_device *udev; 462 void __user *p = (void __user *)arg; 463 struct uinput_ff_upload ff_up; 464 struct uinput_ff_erase ff_erase; 465 struct uinput_request *req; 466 int length; 467 char *phys; 468 469 udev = file->private_data; 470 471 retval = mutex_lock_interruptible(&udev->mutex); 472 if (retval) 473 return retval; 474 475 if (!udev->dev) { 476 retval = uinput_allocate_device(udev); 477 if (retval) 478 goto out; 479 } 480 481 switch (cmd) { 482 case UI_DEV_CREATE: 483 retval = uinput_create_device(udev); 484 break; 485 486 case UI_DEV_DESTROY: 487 uinput_destroy_device(udev); 488 break; 489 490 case UI_SET_EVBIT: 491 retval = uinput_set_bit(arg, evbit, EV_MAX); 492 break; 493 494 case UI_SET_KEYBIT: 495 retval = uinput_set_bit(arg, keybit, KEY_MAX); 496 break; 497 498 case UI_SET_RELBIT: 499 retval = uinput_set_bit(arg, relbit, REL_MAX); 500 break; 501 502 case UI_SET_ABSBIT: 503 retval = uinput_set_bit(arg, absbit, ABS_MAX); 504 break; 505 506 case UI_SET_MSCBIT: 507 retval = uinput_set_bit(arg, mscbit, MSC_MAX); 508 break; 509 510 case UI_SET_LEDBIT: 511 retval = uinput_set_bit(arg, ledbit, LED_MAX); 512 break; 513 514 case UI_SET_SNDBIT: 515 retval = uinput_set_bit(arg, sndbit, SND_MAX); 516 break; 517 518 case UI_SET_FFBIT: 519 retval = uinput_set_bit(arg, ffbit, FF_MAX); 520 break; 521 522 case UI_SET_SWBIT: 523 retval = uinput_set_bit(arg, swbit, SW_MAX); 524 break; 525 526 case UI_SET_PHYS: 527 if (udev->state == UIST_CREATED) { 528 retval = -EINVAL; 529 goto out; 530 } 531 length = strnlen_user(p, 1024); 532 if (length <= 0) { 533 retval = -EFAULT; 534 break; 535 } 536 kfree(udev->dev->phys); 537 udev->dev->phys = phys = kmalloc(length, GFP_KERNEL); 538 if (!phys) { 539 retval = -ENOMEM; 540 break; 541 } 542 if (copy_from_user(phys, p, length)) { 543 udev->dev->phys = NULL; 544 kfree(phys); 545 retval = -EFAULT; 546 break; 547 } 548 phys[length - 1] = '\0'; 549 break; 550 551 case UI_BEGIN_FF_UPLOAD: 552 if (copy_from_user(&ff_up, p, sizeof(ff_up))) { 553 retval = -EFAULT; 554 break; 555 } 556 req = uinput_request_find(udev, ff_up.request_id); 557 if (!(req && req->code == UI_FF_UPLOAD && req->u.upload.effect)) { 558 retval = -EINVAL; 559 break; 560 } 561 ff_up.retval = 0; 562 memcpy(&ff_up.effect, req->u.upload.effect, sizeof(struct ff_effect)); 563 if (req->u.upload.old) 564 memcpy(&ff_up.old, req->u.upload.old, sizeof(struct ff_effect)); 565 else 566 memset(&ff_up.old, 0, sizeof(struct ff_effect)); 567 568 if (copy_to_user(p, &ff_up, sizeof(ff_up))) { 569 retval = -EFAULT; 570 break; 571 } 572 break; 573 574 case UI_BEGIN_FF_ERASE: 575 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 576 retval = -EFAULT; 577 break; 578 } 579 req = uinput_request_find(udev, ff_erase.request_id); 580 if (!(req && req->code == UI_FF_ERASE)) { 581 retval = -EINVAL; 582 break; 583 } 584 ff_erase.retval = 0; 585 ff_erase.effect_id = req->u.effect_id; 586 if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) { 587 retval = -EFAULT; 588 break; 589 } 590 break; 591 592 case UI_END_FF_UPLOAD: 593 if (copy_from_user(&ff_up, p, sizeof(ff_up))) { 594 retval = -EFAULT; 595 break; 596 } 597 req = uinput_request_find(udev, ff_up.request_id); 598 if (!(req && req->code == UI_FF_UPLOAD && req->u.upload.effect)) { 599 retval = -EINVAL; 600 break; 601 } 602 req->retval = ff_up.retval; 603 uinput_request_done(udev, req); 604 break; 605 606 case UI_END_FF_ERASE: 607 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 608 retval = -EFAULT; 609 break; 610 } 611 req = uinput_request_find(udev, ff_erase.request_id); 612 if (!(req && req->code == UI_FF_ERASE)) { 613 retval = -EINVAL; 614 break; 615 } 616 req->retval = ff_erase.retval; 617 uinput_request_done(udev, req); 618 break; 619 620 default: 621 retval = -EINVAL; 622 } 623 624 out: 625 mutex_unlock(&udev->mutex); 626 return retval; 627 } 628 629 static const struct file_operations uinput_fops = { 630 .owner = THIS_MODULE, 631 .open = uinput_open, 632 .release = uinput_release, 633 .read = uinput_read, 634 .write = uinput_write, 635 .poll = uinput_poll, 636 .unlocked_ioctl = uinput_ioctl, 637 }; 638 639 static struct miscdevice uinput_misc = { 640 .fops = &uinput_fops, 641 .minor = UINPUT_MINOR, 642 .name = UINPUT_NAME, 643 }; 644 645 static int __init uinput_init(void) 646 { 647 return misc_register(&uinput_misc); 648 } 649 650 static void __exit uinput_exit(void) 651 { 652 misc_deregister(&uinput_misc); 653 } 654 655 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho"); 656 MODULE_DESCRIPTION("User level driver support for input subsystem"); 657 MODULE_LICENSE("GPL"); 658 MODULE_VERSION("0.3"); 659 660 module_init(uinput_init); 661 module_exit(uinput_exit); 662 663