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 mutex_init(&newdev->mutex); 226 spin_lock_init(&newdev->requests_lock); 227 init_waitqueue_head(&newdev->requests_waitq); 228 init_waitqueue_head(&newdev->waitq); 229 newdev->state = UIST_NEW_DEVICE; 230 231 file->private_data = newdev; 232 233 return 0; 234 } 235 236 static int uinput_validate_absbits(struct input_dev *dev) 237 { 238 unsigned int cnt; 239 int retval = 0; 240 241 for (cnt = 0; cnt < ABS_MAX + 1; cnt++) { 242 if (!test_bit(cnt, dev->absbit)) 243 continue; 244 245 if ((dev->absmax[cnt] <= dev->absmin[cnt])) { 246 printk(KERN_DEBUG 247 "%s: invalid abs[%02x] min:%d max:%d\n", 248 UINPUT_NAME, cnt, 249 dev->absmin[cnt], dev->absmax[cnt]); 250 retval = -EINVAL; 251 break; 252 } 253 254 if (dev->absflat[cnt] > (dev->absmax[cnt] - dev->absmin[cnt])) { 255 printk(KERN_DEBUG 256 "%s: absflat[%02x] out of range: %d " 257 "(min:%d/max:%d)\n", 258 UINPUT_NAME, cnt, dev->absflat[cnt], 259 dev->absmin[cnt], dev->absmax[cnt]); 260 retval = -EINVAL; 261 break; 262 } 263 } 264 return retval; 265 } 266 267 static int uinput_allocate_device(struct uinput_device *udev) 268 { 269 udev->dev = input_allocate_device(); 270 if (!udev->dev) 271 return -ENOMEM; 272 273 udev->dev->event = uinput_dev_event; 274 input_set_drvdata(udev->dev, udev); 275 276 return 0; 277 } 278 279 static int uinput_setup_device(struct uinput_device *udev, const char __user *buffer, size_t count) 280 { 281 struct uinput_user_dev *user_dev; 282 struct input_dev *dev; 283 char *name; 284 int size; 285 int retval; 286 287 if (count != sizeof(struct uinput_user_dev)) 288 return -EINVAL; 289 290 if (!udev->dev) { 291 retval = uinput_allocate_device(udev); 292 if (retval) 293 return retval; 294 } 295 296 dev = udev->dev; 297 298 user_dev = kmalloc(sizeof(struct uinput_user_dev), GFP_KERNEL); 299 if (!user_dev) 300 return -ENOMEM; 301 302 if (copy_from_user(user_dev, buffer, sizeof(struct uinput_user_dev))) { 303 retval = -EFAULT; 304 goto exit; 305 } 306 307 udev->ff_effects_max = user_dev->ff_effects_max; 308 309 size = strnlen(user_dev->name, UINPUT_MAX_NAME_SIZE) + 1; 310 if (!size) { 311 retval = -EINVAL; 312 goto exit; 313 } 314 315 kfree(dev->name); 316 dev->name = name = kmalloc(size, GFP_KERNEL); 317 if (!name) { 318 retval = -ENOMEM; 319 goto exit; 320 } 321 strlcpy(name, user_dev->name, size); 322 323 dev->id.bustype = user_dev->id.bustype; 324 dev->id.vendor = user_dev->id.vendor; 325 dev->id.product = user_dev->id.product; 326 dev->id.version = user_dev->id.version; 327 328 size = sizeof(int) * (ABS_MAX + 1); 329 memcpy(dev->absmax, user_dev->absmax, size); 330 memcpy(dev->absmin, user_dev->absmin, size); 331 memcpy(dev->absfuzz, user_dev->absfuzz, size); 332 memcpy(dev->absflat, user_dev->absflat, size); 333 334 /* check if absmin/absmax/absfuzz/absflat are filled as 335 * told in Documentation/input/input-programming.txt */ 336 if (test_bit(EV_ABS, dev->evbit)) { 337 retval = uinput_validate_absbits(dev); 338 if (retval < 0) 339 goto exit; 340 } 341 342 udev->state = UIST_SETUP_COMPLETE; 343 retval = count; 344 345 exit: 346 kfree(user_dev); 347 return retval; 348 } 349 350 static inline ssize_t uinput_inject_event(struct uinput_device *udev, const char __user *buffer, size_t count) 351 { 352 struct input_event ev; 353 354 if (count != sizeof(struct input_event)) 355 return -EINVAL; 356 357 if (copy_from_user(&ev, buffer, sizeof(struct input_event))) 358 return -EFAULT; 359 360 input_event(udev->dev, ev.type, ev.code, ev.value); 361 362 return sizeof(struct input_event); 363 } 364 365 static ssize_t uinput_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) 366 { 367 struct uinput_device *udev = file->private_data; 368 int retval; 369 370 retval = mutex_lock_interruptible(&udev->mutex); 371 if (retval) 372 return retval; 373 374 retval = udev->state == UIST_CREATED ? 375 uinput_inject_event(udev, buffer, count) : 376 uinput_setup_device(udev, buffer, count); 377 378 mutex_unlock(&udev->mutex); 379 380 return retval; 381 } 382 383 static ssize_t uinput_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos) 384 { 385 struct uinput_device *udev = file->private_data; 386 int retval = 0; 387 388 if (udev->state != UIST_CREATED) 389 return -ENODEV; 390 391 if (udev->head == udev->tail && (file->f_flags & O_NONBLOCK)) 392 return -EAGAIN; 393 394 retval = wait_event_interruptible(udev->waitq, 395 udev->head != udev->tail || udev->state != UIST_CREATED); 396 if (retval) 397 return retval; 398 399 retval = mutex_lock_interruptible(&udev->mutex); 400 if (retval) 401 return retval; 402 403 if (udev->state != UIST_CREATED) { 404 retval = -ENODEV; 405 goto out; 406 } 407 408 while (udev->head != udev->tail && retval + sizeof(struct input_event) <= count) { 409 if (copy_to_user(buffer + retval, &udev->buff[udev->tail], sizeof(struct input_event))) { 410 retval = -EFAULT; 411 goto out; 412 } 413 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE; 414 retval += sizeof(struct input_event); 415 } 416 417 out: 418 mutex_unlock(&udev->mutex); 419 420 return retval; 421 } 422 423 static unsigned int uinput_poll(struct file *file, poll_table *wait) 424 { 425 struct uinput_device *udev = file->private_data; 426 427 poll_wait(file, &udev->waitq, wait); 428 429 if (udev->head != udev->tail) 430 return POLLIN | POLLRDNORM; 431 432 return 0; 433 } 434 435 static int uinput_release(struct inode *inode, struct file *file) 436 { 437 struct uinput_device *udev = file->private_data; 438 439 uinput_destroy_device(udev); 440 kfree(udev); 441 442 return 0; 443 } 444 445 #define uinput_set_bit(_arg, _bit, _max) \ 446 ({ \ 447 int __ret = 0; \ 448 if (udev->state == UIST_CREATED) \ 449 __ret = -EINVAL; \ 450 else if ((_arg) > (_max)) \ 451 __ret = -EINVAL; \ 452 else set_bit((_arg), udev->dev->_bit); \ 453 __ret; \ 454 }) 455 456 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 457 { 458 int retval; 459 struct uinput_device *udev; 460 void __user *p = (void __user *)arg; 461 struct uinput_ff_upload ff_up; 462 struct uinput_ff_erase ff_erase; 463 struct uinput_request *req; 464 int length; 465 char *phys; 466 467 udev = file->private_data; 468 469 retval = mutex_lock_interruptible(&udev->mutex); 470 if (retval) 471 return retval; 472 473 if (!udev->dev) { 474 retval = uinput_allocate_device(udev); 475 if (retval) 476 goto out; 477 } 478 479 switch (cmd) { 480 case UI_DEV_CREATE: 481 retval = uinput_create_device(udev); 482 break; 483 484 case UI_DEV_DESTROY: 485 uinput_destroy_device(udev); 486 break; 487 488 case UI_SET_EVBIT: 489 retval = uinput_set_bit(arg, evbit, EV_MAX); 490 break; 491 492 case UI_SET_KEYBIT: 493 retval = uinput_set_bit(arg, keybit, KEY_MAX); 494 break; 495 496 case UI_SET_RELBIT: 497 retval = uinput_set_bit(arg, relbit, REL_MAX); 498 break; 499 500 case UI_SET_ABSBIT: 501 retval = uinput_set_bit(arg, absbit, ABS_MAX); 502 break; 503 504 case UI_SET_MSCBIT: 505 retval = uinput_set_bit(arg, mscbit, MSC_MAX); 506 break; 507 508 case UI_SET_LEDBIT: 509 retval = uinput_set_bit(arg, ledbit, LED_MAX); 510 break; 511 512 case UI_SET_SNDBIT: 513 retval = uinput_set_bit(arg, sndbit, SND_MAX); 514 break; 515 516 case UI_SET_FFBIT: 517 retval = uinput_set_bit(arg, ffbit, FF_MAX); 518 break; 519 520 case UI_SET_SWBIT: 521 retval = uinput_set_bit(arg, swbit, SW_MAX); 522 break; 523 524 case UI_SET_PHYS: 525 if (udev->state == UIST_CREATED) { 526 retval = -EINVAL; 527 goto out; 528 } 529 length = strnlen_user(p, 1024); 530 if (length <= 0) { 531 retval = -EFAULT; 532 break; 533 } 534 kfree(udev->dev->phys); 535 udev->dev->phys = phys = kmalloc(length, GFP_KERNEL); 536 if (!phys) { 537 retval = -ENOMEM; 538 break; 539 } 540 if (copy_from_user(phys, p, length)) { 541 udev->dev->phys = NULL; 542 kfree(phys); 543 retval = -EFAULT; 544 break; 545 } 546 phys[length - 1] = '\0'; 547 break; 548 549 case UI_BEGIN_FF_UPLOAD: 550 if (copy_from_user(&ff_up, p, sizeof(ff_up))) { 551 retval = -EFAULT; 552 break; 553 } 554 req = uinput_request_find(udev, ff_up.request_id); 555 if (!(req && req->code == UI_FF_UPLOAD && req->u.upload.effect)) { 556 retval = -EINVAL; 557 break; 558 } 559 ff_up.retval = 0; 560 memcpy(&ff_up.effect, req->u.upload.effect, sizeof(struct ff_effect)); 561 if (req->u.upload.old) 562 memcpy(&ff_up.old, req->u.upload.old, sizeof(struct ff_effect)); 563 else 564 memset(&ff_up.old, 0, sizeof(struct ff_effect)); 565 566 if (copy_to_user(p, &ff_up, sizeof(ff_up))) { 567 retval = -EFAULT; 568 break; 569 } 570 break; 571 572 case UI_BEGIN_FF_ERASE: 573 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 574 retval = -EFAULT; 575 break; 576 } 577 req = uinput_request_find(udev, ff_erase.request_id); 578 if (!(req && req->code == UI_FF_ERASE)) { 579 retval = -EINVAL; 580 break; 581 } 582 ff_erase.retval = 0; 583 ff_erase.effect_id = req->u.effect_id; 584 if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) { 585 retval = -EFAULT; 586 break; 587 } 588 break; 589 590 case UI_END_FF_UPLOAD: 591 if (copy_from_user(&ff_up, p, sizeof(ff_up))) { 592 retval = -EFAULT; 593 break; 594 } 595 req = uinput_request_find(udev, ff_up.request_id); 596 if (!(req && req->code == UI_FF_UPLOAD && req->u.upload.effect)) { 597 retval = -EINVAL; 598 break; 599 } 600 req->retval = ff_up.retval; 601 uinput_request_done(udev, req); 602 break; 603 604 case UI_END_FF_ERASE: 605 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 606 retval = -EFAULT; 607 break; 608 } 609 req = uinput_request_find(udev, ff_erase.request_id); 610 if (!(req && req->code == UI_FF_ERASE)) { 611 retval = -EINVAL; 612 break; 613 } 614 req->retval = ff_erase.retval; 615 uinput_request_done(udev, req); 616 break; 617 618 default: 619 retval = -EINVAL; 620 } 621 622 out: 623 mutex_unlock(&udev->mutex); 624 return retval; 625 } 626 627 static const struct file_operations uinput_fops = { 628 .owner = THIS_MODULE, 629 .open = uinput_open, 630 .release = uinput_release, 631 .read = uinput_read, 632 .write = uinput_write, 633 .poll = uinput_poll, 634 .unlocked_ioctl = uinput_ioctl, 635 }; 636 637 static struct miscdevice uinput_misc = { 638 .fops = &uinput_fops, 639 .minor = UINPUT_MINOR, 640 .name = UINPUT_NAME, 641 }; 642 643 static int __init uinput_init(void) 644 { 645 return misc_register(&uinput_misc); 646 } 647 648 static void __exit uinput_exit(void) 649 { 650 misc_deregister(&uinput_misc); 651 } 652 653 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho"); 654 MODULE_DESCRIPTION("User level driver support for input subsystem"); 655 MODULE_LICENSE("GPL"); 656 MODULE_VERSION("0.3"); 657 658 module_init(uinput_init); 659 module_exit(uinput_exit); 660 661