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 #include <linux/smp_lock.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 lock_kernel(); 227 mutex_init(&newdev->mutex); 228 spin_lock_init(&newdev->requests_lock); 229 init_waitqueue_head(&newdev->requests_waitq); 230 init_waitqueue_head(&newdev->waitq); 231 newdev->state = UIST_NEW_DEVICE; 232 233 file->private_data = newdev; 234 unlock_kernel(); 235 236 return 0; 237 } 238 239 static int uinput_validate_absbits(struct input_dev *dev) 240 { 241 unsigned int cnt; 242 int retval = 0; 243 244 for (cnt = 0; cnt < ABS_MAX + 1; cnt++) { 245 if (!test_bit(cnt, dev->absbit)) 246 continue; 247 248 if ((dev->absmax[cnt] <= dev->absmin[cnt])) { 249 printk(KERN_DEBUG 250 "%s: invalid abs[%02x] min:%d max:%d\n", 251 UINPUT_NAME, cnt, 252 dev->absmin[cnt], dev->absmax[cnt]); 253 retval = -EINVAL; 254 break; 255 } 256 257 if (dev->absflat[cnt] > (dev->absmax[cnt] - dev->absmin[cnt])) { 258 printk(KERN_DEBUG 259 "%s: absflat[%02x] out of range: %d " 260 "(min:%d/max:%d)\n", 261 UINPUT_NAME, cnt, dev->absflat[cnt], 262 dev->absmin[cnt], dev->absmax[cnt]); 263 retval = -EINVAL; 264 break; 265 } 266 } 267 return retval; 268 } 269 270 static int uinput_allocate_device(struct uinput_device *udev) 271 { 272 udev->dev = input_allocate_device(); 273 if (!udev->dev) 274 return -ENOMEM; 275 276 udev->dev->event = uinput_dev_event; 277 input_set_drvdata(udev->dev, udev); 278 279 return 0; 280 } 281 282 static int uinput_setup_device(struct uinput_device *udev, const char __user *buffer, size_t count) 283 { 284 struct uinput_user_dev *user_dev; 285 struct input_dev *dev; 286 char *name; 287 int size; 288 int retval; 289 290 if (count != sizeof(struct uinput_user_dev)) 291 return -EINVAL; 292 293 if (!udev->dev) { 294 retval = uinput_allocate_device(udev); 295 if (retval) 296 return retval; 297 } 298 299 dev = udev->dev; 300 301 user_dev = kmalloc(sizeof(struct uinput_user_dev), GFP_KERNEL); 302 if (!user_dev) 303 return -ENOMEM; 304 305 if (copy_from_user(user_dev, buffer, sizeof(struct uinput_user_dev))) { 306 retval = -EFAULT; 307 goto exit; 308 } 309 310 udev->ff_effects_max = user_dev->ff_effects_max; 311 312 size = strnlen(user_dev->name, UINPUT_MAX_NAME_SIZE) + 1; 313 if (!size) { 314 retval = -EINVAL; 315 goto exit; 316 } 317 318 kfree(dev->name); 319 dev->name = name = kmalloc(size, GFP_KERNEL); 320 if (!name) { 321 retval = -ENOMEM; 322 goto exit; 323 } 324 strlcpy(name, user_dev->name, size); 325 326 dev->id.bustype = user_dev->id.bustype; 327 dev->id.vendor = user_dev->id.vendor; 328 dev->id.product = user_dev->id.product; 329 dev->id.version = user_dev->id.version; 330 331 size = sizeof(int) * (ABS_MAX + 1); 332 memcpy(dev->absmax, user_dev->absmax, size); 333 memcpy(dev->absmin, user_dev->absmin, size); 334 memcpy(dev->absfuzz, user_dev->absfuzz, size); 335 memcpy(dev->absflat, user_dev->absflat, size); 336 337 /* check if absmin/absmax/absfuzz/absflat are filled as 338 * told in Documentation/input/input-programming.txt */ 339 if (test_bit(EV_ABS, dev->evbit)) { 340 retval = uinput_validate_absbits(dev); 341 if (retval < 0) 342 goto exit; 343 } 344 345 udev->state = UIST_SETUP_COMPLETE; 346 retval = count; 347 348 exit: 349 kfree(user_dev); 350 return retval; 351 } 352 353 static inline ssize_t uinput_inject_event(struct uinput_device *udev, const char __user *buffer, size_t count) 354 { 355 struct input_event ev; 356 357 if (count != sizeof(struct input_event)) 358 return -EINVAL; 359 360 if (copy_from_user(&ev, buffer, sizeof(struct input_event))) 361 return -EFAULT; 362 363 input_event(udev->dev, ev.type, ev.code, ev.value); 364 365 return sizeof(struct input_event); 366 } 367 368 static ssize_t uinput_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) 369 { 370 struct uinput_device *udev = file->private_data; 371 int retval; 372 373 retval = mutex_lock_interruptible(&udev->mutex); 374 if (retval) 375 return retval; 376 377 retval = udev->state == UIST_CREATED ? 378 uinput_inject_event(udev, buffer, count) : 379 uinput_setup_device(udev, buffer, count); 380 381 mutex_unlock(&udev->mutex); 382 383 return retval; 384 } 385 386 static ssize_t uinput_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos) 387 { 388 struct uinput_device *udev = file->private_data; 389 int retval = 0; 390 391 if (udev->state != UIST_CREATED) 392 return -ENODEV; 393 394 if (udev->head == udev->tail && (file->f_flags & O_NONBLOCK)) 395 return -EAGAIN; 396 397 retval = wait_event_interruptible(udev->waitq, 398 udev->head != udev->tail || udev->state != UIST_CREATED); 399 if (retval) 400 return retval; 401 402 retval = mutex_lock_interruptible(&udev->mutex); 403 if (retval) 404 return retval; 405 406 if (udev->state != UIST_CREATED) { 407 retval = -ENODEV; 408 goto out; 409 } 410 411 while (udev->head != udev->tail && retval + sizeof(struct input_event) <= count) { 412 if (copy_to_user(buffer + retval, &udev->buff[udev->tail], sizeof(struct input_event))) { 413 retval = -EFAULT; 414 goto out; 415 } 416 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE; 417 retval += sizeof(struct input_event); 418 } 419 420 out: 421 mutex_unlock(&udev->mutex); 422 423 return retval; 424 } 425 426 static unsigned int uinput_poll(struct file *file, poll_table *wait) 427 { 428 struct uinput_device *udev = file->private_data; 429 430 poll_wait(file, &udev->waitq, wait); 431 432 if (udev->head != udev->tail) 433 return POLLIN | POLLRDNORM; 434 435 return 0; 436 } 437 438 static int uinput_release(struct inode *inode, struct file *file) 439 { 440 struct uinput_device *udev = file->private_data; 441 442 uinput_destroy_device(udev); 443 kfree(udev); 444 445 return 0; 446 } 447 448 #define uinput_set_bit(_arg, _bit, _max) \ 449 ({ \ 450 int __ret = 0; \ 451 if (udev->state == UIST_CREATED) \ 452 __ret = -EINVAL; \ 453 else if ((_arg) > (_max)) \ 454 __ret = -EINVAL; \ 455 else set_bit((_arg), udev->dev->_bit); \ 456 __ret; \ 457 }) 458 459 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 460 { 461 int retval; 462 struct uinput_device *udev; 463 void __user *p = (void __user *)arg; 464 struct uinput_ff_upload ff_up; 465 struct uinput_ff_erase ff_erase; 466 struct uinput_request *req; 467 int length; 468 char *phys; 469 470 udev = file->private_data; 471 472 retval = mutex_lock_interruptible(&udev->mutex); 473 if (retval) 474 return retval; 475 476 if (!udev->dev) { 477 retval = uinput_allocate_device(udev); 478 if (retval) 479 goto out; 480 } 481 482 switch (cmd) { 483 case UI_DEV_CREATE: 484 retval = uinput_create_device(udev); 485 break; 486 487 case UI_DEV_DESTROY: 488 uinput_destroy_device(udev); 489 break; 490 491 case UI_SET_EVBIT: 492 retval = uinput_set_bit(arg, evbit, EV_MAX); 493 break; 494 495 case UI_SET_KEYBIT: 496 retval = uinput_set_bit(arg, keybit, KEY_MAX); 497 break; 498 499 case UI_SET_RELBIT: 500 retval = uinput_set_bit(arg, relbit, REL_MAX); 501 break; 502 503 case UI_SET_ABSBIT: 504 retval = uinput_set_bit(arg, absbit, ABS_MAX); 505 break; 506 507 case UI_SET_MSCBIT: 508 retval = uinput_set_bit(arg, mscbit, MSC_MAX); 509 break; 510 511 case UI_SET_LEDBIT: 512 retval = uinput_set_bit(arg, ledbit, LED_MAX); 513 break; 514 515 case UI_SET_SNDBIT: 516 retval = uinput_set_bit(arg, sndbit, SND_MAX); 517 break; 518 519 case UI_SET_FFBIT: 520 retval = uinput_set_bit(arg, ffbit, FF_MAX); 521 break; 522 523 case UI_SET_SWBIT: 524 retval = uinput_set_bit(arg, swbit, SW_MAX); 525 break; 526 527 case UI_SET_PHYS: 528 if (udev->state == UIST_CREATED) { 529 retval = -EINVAL; 530 goto out; 531 } 532 length = strnlen_user(p, 1024); 533 if (length <= 0) { 534 retval = -EFAULT; 535 break; 536 } 537 kfree(udev->dev->phys); 538 udev->dev->phys = phys = kmalloc(length, GFP_KERNEL); 539 if (!phys) { 540 retval = -ENOMEM; 541 break; 542 } 543 if (copy_from_user(phys, p, length)) { 544 udev->dev->phys = NULL; 545 kfree(phys); 546 retval = -EFAULT; 547 break; 548 } 549 phys[length - 1] = '\0'; 550 break; 551 552 case UI_BEGIN_FF_UPLOAD: 553 if (copy_from_user(&ff_up, p, sizeof(ff_up))) { 554 retval = -EFAULT; 555 break; 556 } 557 req = uinput_request_find(udev, ff_up.request_id); 558 if (!(req && req->code == UI_FF_UPLOAD && req->u.upload.effect)) { 559 retval = -EINVAL; 560 break; 561 } 562 ff_up.retval = 0; 563 memcpy(&ff_up.effect, req->u.upload.effect, sizeof(struct ff_effect)); 564 if (req->u.upload.old) 565 memcpy(&ff_up.old, req->u.upload.old, sizeof(struct ff_effect)); 566 else 567 memset(&ff_up.old, 0, sizeof(struct ff_effect)); 568 569 if (copy_to_user(p, &ff_up, sizeof(ff_up))) { 570 retval = -EFAULT; 571 break; 572 } 573 break; 574 575 case UI_BEGIN_FF_ERASE: 576 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 577 retval = -EFAULT; 578 break; 579 } 580 req = uinput_request_find(udev, ff_erase.request_id); 581 if (!(req && req->code == UI_FF_ERASE)) { 582 retval = -EINVAL; 583 break; 584 } 585 ff_erase.retval = 0; 586 ff_erase.effect_id = req->u.effect_id; 587 if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) { 588 retval = -EFAULT; 589 break; 590 } 591 break; 592 593 case UI_END_FF_UPLOAD: 594 if (copy_from_user(&ff_up, p, sizeof(ff_up))) { 595 retval = -EFAULT; 596 break; 597 } 598 req = uinput_request_find(udev, ff_up.request_id); 599 if (!(req && req->code == UI_FF_UPLOAD && req->u.upload.effect)) { 600 retval = -EINVAL; 601 break; 602 } 603 req->retval = ff_up.retval; 604 uinput_request_done(udev, req); 605 break; 606 607 case UI_END_FF_ERASE: 608 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 609 retval = -EFAULT; 610 break; 611 } 612 req = uinput_request_find(udev, ff_erase.request_id); 613 if (!(req && req->code == UI_FF_ERASE)) { 614 retval = -EINVAL; 615 break; 616 } 617 req->retval = ff_erase.retval; 618 uinput_request_done(udev, req); 619 break; 620 621 default: 622 retval = -EINVAL; 623 } 624 625 out: 626 mutex_unlock(&udev->mutex); 627 return retval; 628 } 629 630 static const struct file_operations uinput_fops = { 631 .owner = THIS_MODULE, 632 .open = uinput_open, 633 .release = uinput_release, 634 .read = uinput_read, 635 .write = uinput_write, 636 .poll = uinput_poll, 637 .unlocked_ioctl = uinput_ioctl, 638 }; 639 640 static struct miscdevice uinput_misc = { 641 .fops = &uinput_fops, 642 .minor = UINPUT_MINOR, 643 .name = UINPUT_NAME, 644 }; 645 646 static int __init uinput_init(void) 647 { 648 return misc_register(&uinput_misc); 649 } 650 651 static void __exit uinput_exit(void) 652 { 653 misc_deregister(&uinput_misc); 654 } 655 656 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho"); 657 MODULE_DESCRIPTION("User level driver support for input subsystem"); 658 MODULE_LICENSE("GPL"); 659 MODULE_VERSION("0.3"); 660 661 module_init(uinput_init); 662 module_exit(uinput_exit); 663 664