drivers/hid/usbhid/hiddev.c

   1 /*
   2  *  Copyright (c) 2001 Paul Stewart
   3  *  Copyright (c) 2001 Vojtech Pavlik
   4  *
   5  *  HID char devices, giving access to raw HID device events.
   6  *
   7  */
   8
   9 /*
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  23  *
  24  * Should you need to contact me, the author, you can do so either by
  25  * e-mail - mail your message to Paul Stewart <stewart@wetlogic.net>
  26  */
  27
  28 #include <linux/poll.h>
  29 #include <linux/slab.h>
  30 #include <linux/module.h>
  31 #include <linux/init.h>
  32 #include <linux/input.h>
  33 #include <linux/usb.h>
  34 #include <linux/hid.h>
  35 #include <linux/hiddev.h>
  36 #include <linux/compat.h>
  37 #include "usbhid.h"
  38
  39 #ifdef CONFIG_USB_DYNAMIC_MINORS
  40 #define HIDDEV_MINOR_BASE       0
  41 #define HIDDEV_MINORS           256
  42 #else
  43 #define HIDDEV_MINOR_BASE       96
  44 #define HIDDEV_MINORS           16
  45 #endif
  46 #define HIDDEV_BUFFER_SIZE      2048
  47
  48 struct hiddev {
  49         int exist;
  50         int open;
  51         struct mutex existancelock;
  52         wait_queue_head_t wait;
  53         struct hid_device *hid;
  54         struct list_head list;
  55         spinlock_t list_lock;
  56 };
  57
  58 struct hiddev_list {
  59         struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
  60         int head;
  61         int tail;
  62         unsigned flags;
  63         struct fasync_struct *fasync;
  64         struct hiddev *hiddev;
  65         struct list_head node;
  66         struct mutex thread_lock;
  67 };
  68
  69 /*
  70  * Find a report, given the report's type and ID.  The ID can be specified
  71  * indirectly by REPORT_ID_FIRST (which returns the first report of the given
  72  * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
  73  * given type which follows old_id.
  74  */
  75 static struct hid_report *
  76 hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
  77 {
  78         unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
  79         unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK;
  80         struct hid_report_enum *report_enum;
  81         struct hid_report *report;
  82         struct list_head *list;
  83
  84         if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
  85             rinfo->report_type > HID_REPORT_TYPE_MAX)
  86                 return NULL;
  87
  88         report_enum = hid->report_enum +
  89                 (rinfo->report_type - HID_REPORT_TYPE_MIN);
  90
  91         switch (flags) {
  92         case 0: /* Nothing to do -- report_id is already set correctly */
  93                 break;
  94
  95         case HID_REPORT_ID_FIRST:
  96                 if (list_empty(&report_enum->report_list))
  97                         return NULL;
  98
  99                 list = report_enum->report_list.next;
 100                 report = list_entry(list, struct hid_report, list);
 101                 rinfo->report_id = report->id;
 102                 break;
 103
 104         case HID_REPORT_ID_NEXT:
 105                 report = report_enum->report_id_hash[rid];
 106                 if (!report)
 107                         return NULL;
 108
 109                 list = report->list.next;
 110                 if (list == &report_enum->report_list)
 111                         return NULL;
 112
 113                 report = list_entry(list, struct hid_report, list);
 114                 rinfo->report_id = report->id;
 115                 break;
 116
 117         default:
 118                 return NULL;
 119         }
 120
 121         return report_enum->report_id_hash[rinfo->report_id];
 122 }
 123
 124 /*
 125  * Perform an exhaustive search of the report table for a usage, given its
 126  * type and usage id.
 127  */
 128 static struct hid_field *
 129 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
 130 {
 131         int i, j;
 132         struct hid_report *report;
 133         struct hid_report_enum *report_enum;
 134         struct hid_field *field;
 135
 136         if (uref->report_type < HID_REPORT_TYPE_MIN ||
 137             uref->report_type > HID_REPORT_TYPE_MAX)
 138                 return NULL;
 139
 140         report_enum = hid->report_enum +
 141                 (uref->report_type - HID_REPORT_TYPE_MIN);
 142
 143         list_for_each_entry(report, &report_enum->report_list, list) {
 144                 for (i = 0; i < report->maxfield; i++) {
 145                         field = report->field[i];
 146                         for (j = 0; j < field->maxusage; j++) {
 147                                 if (field->usage[j].hid == uref->usage_code) {
 148                                         uref->report_id = report->id;
 149                                         uref->field_index = i;
 150                                         uref->usage_index = j;
 151                                         return field;
 152                                 }
 153                         }
 154                 }
 155         }
 156
 157         return NULL;
 158 }
 159
 160 static void hiddev_send_event(struct hid_device *hid,
 161                               struct hiddev_usage_ref *uref)
 162 {
 163         struct hiddev *hiddev = hid->hiddev;
 164         struct hiddev_list *list;
 165         unsigned long flags;
 166
 167         spin_lock_irqsave(&hiddev->list_lock, flags);
 168         list_for_each_entry(list, &hiddev->list, node) {
 169                 if (uref->field_index != HID_FIELD_INDEX_NONE ||
 170                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 171                         list->buffer[list->head] = *uref;
 172                         list->head = (list->head + 1) &
 173                                 (HIDDEV_BUFFER_SIZE - 1);
 174                         kill_fasync(&list->fasync, SIGIO, POLL_IN);
 175                 }
 176         }
 177         spin_unlock_irqrestore(&hiddev->list_lock, flags);
 178
 179         wake_up_interruptible(&hiddev->wait);
 180 }
 181
 182 /*
 183  * This is where hid.c calls into hiddev to pass an event that occurred over
 184  * the interrupt pipe
 185  */
 186 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
 187                       struct hid_usage *usage, __s32 value)
 188 {
 189         unsigned type = field->report_type;
 190         struct hiddev_usage_ref uref;
 191
 192         uref.report_type =
 193           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
 194           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
 195            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
 196         uref.report_id = field->report->id;
 197         uref.field_index = field->index;
 198         uref.usage_index = (usage - field->usage);
 199         uref.usage_code = usage->hid;
 200         uref.value = value;
 201
 202         hiddev_send_event(hid, &uref);
 203 }
 204 EXPORT_SYMBOL_GPL(hiddev_hid_event);
 205
 206 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
 207 {
 208         unsigned type = report->type;
 209         struct hiddev_usage_ref uref;
 210
 211         memset(&uref, 0, sizeof(uref));
 212         uref.report_type =
 213           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
 214           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
 215            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
 216         uref.report_id = report->id;
 217         uref.field_index = HID_FIELD_INDEX_NONE;
 218
 219         hiddev_send_event(hid, &uref);
 220 }
 221
 222 /*
 223  * fasync file op
 224  */
 225 static int hiddev_fasync(int fd, struct file *file, int on)
 226 {
 227         struct hiddev_list *list = file->private_data;
 228
 229         return fasync_helper(fd, file, on, &list->fasync);
 230 }
 231
 232
 233 /*
 234  * release file op
 235  */
 236 static int hiddev_release(struct inode * inode, struct file * file)
 237 {
 238         struct hiddev_list *list = file->private_data;
 239         unsigned long flags;
 240
 241         spin_lock_irqsave(&list->hiddev->list_lock, flags);
 242         list_del(&list->node);
 243         spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
 244
 245         if (!--list->hiddev->open) {
 246                 if (list->hiddev->exist) {
 247                         usbhid_close(list->hiddev->hid);
 248                         usbhid_put_power(list->hiddev->hid);
 249                 } else {
 250                         kfree(list->hiddev);
 251                 }
 252         }
 253
 254         kfree(list);
 255
 256         return 0;
 257 }
 258
 259 /*
 260  * open file op
 261  */
 262 static int hiddev_open(struct inode *inode, struct file *file)
 263 {
 264         struct hiddev_list *list;
 265         struct usb_interface *intf;
 266         struct hid_device *hid;
 267         struct hiddev *hiddev;
 268         int res;
 269
 270         intf = usbhid_find_interface(iminor(inode));
 271         if (!intf)
 272                 return -ENODEV;
 273         hid = usb_get_intfdata(intf);
 274         hiddev = hid->hiddev;
 275
 276         if (!(list = kzalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
 277                 return -ENOMEM;
 278         mutex_init(&list->thread_lock);
 279         list->hiddev = hiddev;
 280         file->private_data = list;
 281
 282         /*
 283          * no need for locking because the USB major number
 284          * is shared which usbcore guards against disconnect
 285          */
 286         if (list->hiddev->exist) {
 287                 if (!list->hiddev->open++) {
 288                         res = usbhid_open(hiddev->hid);
 289                         if (res < 0) {
 290                                 res = -EIO;
 291                                 goto bail;
 292                         }
 293                 }
 294         } else {
 295                 res = -ENODEV;
 296                 goto bail;
 297         }
 298
 299         spin_lock_irq(&list->hiddev->list_lock);
 300         list_add_tail(&list->node, &hiddev->list);
 301         spin_unlock_irq(&list->hiddev->list_lock);
 302
 303         if (!list->hiddev->open++)
 304                 if (list->hiddev->exist) {
 305                         struct hid_device *hid = hiddev->hid;
 306                         res = usbhid_get_power(hid);
 307                         if (res < 0) {
 308                                 res = -EIO;
 309                                 goto bail;
 310                         }
 311                         usbhid_open(hid);
 312                 }
 313         return 0;
 314 bail:
 315         file->private_data = NULL;
 316         kfree(list);
 317         return res;
 318 }
 319
 320 /*
 321  * "write" file op
 322  */
 323 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
 324 {
 325         return -EINVAL;
 326 }
 327
 328 /*
 329  * "read" file op
 330  */
 331 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
 332 {
 333         DEFINE_WAIT(wait);
 334         struct hiddev_list *list = file->private_data;
 335         int event_size;
 336         int retval;
 337
 338         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
 339                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
 340
 341         if (count < event_size)
 342                 return 0;
 343
 344         /* lock against other threads */
 345         retval = mutex_lock_interruptible(&list->thread_lock);
 346         if (retval)
 347                 return -ERESTARTSYS;
 348
 349         while (retval == 0) {
 350                 if (list->head == list->tail) {
 351                         prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);
 352
 353                         while (list->head == list->tail) {
 354                                 if (file->f_flags & O_NONBLOCK) {
 355                                         retval = -EAGAIN;
 356                                         break;
 357                                 }
 358                                 if (signal_pending(current)) {
 359                                         retval = -ERESTARTSYS;
 360                                         break;
 361                                 }
 362                                 if (!list->hiddev->exist) {
 363                                         retval = -EIO;
 364                                         break;
 365                                 }
 366
 367                                 /* let O_NONBLOCK tasks run */
 368                                 mutex_unlock(&list->thread_lock);
 369                                 schedule();
 370                                 if (mutex_lock_interruptible(&list->thread_lock))
 371                                         return -EINTR;
 372                                 set_current_state(TASK_INTERRUPTIBLE);
 373                         }
 374                         finish_wait(&list->hiddev->wait, &wait);
 375
 376                 }
 377
 378                 if (retval) {
 379                         mutex_unlock(&list->thread_lock);
 380                         return retval;
 381                 }
 382
 383
 384                 while (list->head != list->tail &&
 385                        retval + event_size <= count) {
 386                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
 387                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
 388                                         struct hiddev_event event;
 389
 390                                         event.hid = list->buffer[list->tail].usage_code;
 391                                         event.value = list->buffer[list->tail].value;
 392                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {
 393                                                 mutex_unlock(&list->thread_lock);
 394                                                 return -EFAULT;
 395                                         }
 396                                         retval += sizeof(struct hiddev_event);
 397                                 }
 398                         } else {
 399                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
 400                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 401
 402                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {
 403                                                 mutex_unlock(&list->thread_lock);
 404                                                 return -EFAULT;
 405                                         }
 406                                         retval += sizeof(struct hiddev_usage_ref);
 407                                 }
 408                         }
 409                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
 410                 }
 411
 412         }
 413         mutex_unlock(&list->thread_lock);
 414
 415         return retval;
 416 }
 417
 418 /*
 419  * "poll" file op
 420  * No kernel lock - fine
 421  */
 422 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
 423 {
 424         struct hiddev_list *list = file->private_data;
 425
 426         poll_wait(file, &list->hiddev->wait, wait);
 427         if (list->head != list->tail)
 428                 return POLLIN | POLLRDNORM;
 429         if (!list->hiddev->exist)
 430                 return POLLERR | POLLHUP;
 431         return 0;
 432 }
 433
 434 /*
 435  * "ioctl" file op
 436  */
 437 static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 438 {
 439         struct hid_device *hid = hiddev->hid;
 440         struct hiddev_report_info rinfo;
 441         struct hiddev_usage_ref_multi *uref_multi = NULL;
 442         struct hiddev_usage_ref *uref;
 443         struct hid_report *report;
 444         struct hid_field *field;
 445         int i;
 446
 447         uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
 448         if (!uref_multi)
 449                 return -ENOMEM;
 450         uref = &uref_multi->uref;
 451         if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
 452                 if (copy_from_user(uref_multi, user_arg,
 453                                    sizeof(*uref_multi)))
 454                         goto fault;
 455         } else {
 456                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
 457                         goto fault;
 458         }
 459
 460         switch (cmd) {
 461         case HIDIOCGUCODE:
 462                 rinfo.report_type = uref->report_type;
 463                 rinfo.report_id = uref->report_id;
 464                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 465                         goto inval;
 466
 467                 if (uref->field_index >= report->maxfield)
 468                         goto inval;
 469
 470                 field = report->field[uref->field_index];
 471                 if (uref->usage_index >= field->maxusage)
 472                         goto inval;
 473
 474                 uref->usage_code = field->usage[uref->usage_index].hid;
 475
 476                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
 477                         goto fault;
 478
 479                 goto goodreturn;
 480
 481         default:
 482                 if (cmd != HIDIOCGUSAGE &&
 483                     cmd != HIDIOCGUSAGES &&
 484                     uref->report_type == HID_REPORT_TYPE_INPUT)
 485                         goto inval;
 486
 487                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
 488                         field = hiddev_lookup_usage(hid, uref);
 489                         if (field == NULL)
 490                                 goto inval;
 491                 } else {
 492                         rinfo.report_type = uref->report_type;
 493                         rinfo.report_id = uref->report_id;
 494                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 495                                 goto inval;
 496
 497                         if (uref->field_index >= report->maxfield)
 498                                 goto inval;
 499
 500                         field = report->field[uref->field_index];
 501
 502                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
 503                                 if (uref->usage_index >= field->maxusage)
 504                                         goto inval;
 505                         } else if (uref->usage_index >= field->report_count)
 506                                 goto inval;
 507
 508                         else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
 509                                  (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
 510                                   uref->usage_index + uref_multi->num_values > field->report_count))
 511                                 goto inval;
 512                         }
 513
 514                 switch (cmd) {
 515                 case HIDIOCGUSAGE:
 516                         uref->value = field->value[uref->usage_index];
 517                         if (copy_to_user(user_arg, uref, sizeof(*uref)))
 518                                 goto fault;
 519                         goto goodreturn;
 520
 521                 case HIDIOCSUSAGE:
 522                         field->value[uref->usage_index] = uref->value;
 523                         goto goodreturn;
 524
 525                 case HIDIOCGCOLLECTIONINDEX:
 526                         i = field->usage[uref->usage_index].collection_index;
 527                         kfree(uref_multi);
 528                         return i;
 529                 case HIDIOCGUSAGES:
 530                         for (i = 0; i < uref_multi->num_values; i++)
 531                                 uref_multi->values[i] =
 532                                     field->value[uref->usage_index + i];
 533                         if (copy_to_user(user_arg, uref_multi,
 534                                          sizeof(*uref_multi)))
 535                                 goto fault;
 536                         goto goodreturn;
 537                 case HIDIOCSUSAGES:
 538                         for (i = 0; i < uref_multi->num_values; i++)
 539                                 field->value[uref->usage_index + i] =
 540                                     uref_multi->values[i];
 541                         goto goodreturn;
 542                 }
 543
 544 goodreturn:
 545                 kfree(uref_multi);
 546                 return 0;
 547 fault:
 548                 kfree(uref_multi);
 549                 return -EFAULT;
 550 inval:
 551                 kfree(uref_multi);
 552                 return -EINVAL;
 553         }
 554 }
 555
 556 static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 557 {
 558         struct hid_device *hid = hiddev->hid;
 559         struct usb_device *dev = hid_to_usb_dev(hid);
 560         int idx, len;
 561         char *buf;
 562
 563         if (get_user(idx, (int __user *)user_arg))
 564                 return -EFAULT;
 565
 566         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
 567                 return -ENOMEM;
 568
 569         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
 570                 kfree(buf);
 571                 return -EINVAL;
 572         }
 573
 574         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
 575                 kfree(buf);
 576                 return -EFAULT;
 577         }
 578
 579         kfree(buf);
 580
 581         return len;
 582 }
 583
 584 static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 585 {
 586         struct hiddev_list *list = file->private_data;
 587         struct hiddev *hiddev = list->hiddev;
 588         struct hid_device *hid;
 589         struct hiddev_collection_info cinfo;
 590         struct hiddev_report_info rinfo;
 591         struct hiddev_field_info finfo;
 592         struct hiddev_devinfo dinfo;
 593         struct hid_report *report;
 594         struct hid_field *field;
 595         void __user *user_arg = (void __user *)arg;
 596         int i, r = -EINVAL;
 597
 598         /* Called without BKL by compat methods so no BKL taken */
 599
 600         mutex_lock(&hiddev->existancelock);
 601         if (!hiddev->exist) {
 602                 r = -ENODEV;
 603                 goto ret_unlock;
 604         }
 605
 606         hid = hiddev->hid;
 607
 608         switch (cmd) {
 609
 610         case HIDIOCGVERSION:
 611                 r = put_user(HID_VERSION, (int __user *)arg) ?
 612                         -EFAULT : 0;
 613                 break;
 614
 615         case HIDIOCAPPLICATION:
 616                 if (arg < 0 || arg >= hid->maxapplication)
 617                         break;
 618
 619                 for (i = 0; i < hid->maxcollection; i++)
 620                         if (hid->collection[i].type ==
 621                             HID_COLLECTION_APPLICATION && arg-- == 0)
 622                                 break;
 623
 624                 if (i < hid->maxcollection)
 625                         r = hid->collection[i].usage;
 626                 break;
 627
 628         case HIDIOCGDEVINFO:
 629                 {
 630                         struct usb_device *dev = hid_to_usb_dev(hid);
 631                         struct usbhid_device *usbhid = hid->driver_data;
 632
 633                         dinfo.bustype = BUS_USB;
 634                         dinfo.busnum = dev->bus->busnum;
 635                         dinfo.devnum = dev->devnum;
 636                         dinfo.ifnum = usbhid->ifnum;
 637                         dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
 638                         dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
 639                         dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
 640                         dinfo.num_applications = hid->maxapplication;
 641
 642                         r = copy_to_user(user_arg, &dinfo, sizeof(dinfo)) ?
 643                                 -EFAULT : 0;
 644                         break;
 645                 }
 646
 647         case HIDIOCGFLAG:
 648                 r = put_user(list->flags, (int __user *)arg) ?
 649                         -EFAULT : 0;
 650                 break;
 651
 652         case HIDIOCSFLAG:
 653                 {
 654                         int newflags;
 655
 656                         if (get_user(newflags, (int __user *)arg)) {
 657                                 r = -EFAULT;
 658                                 break;
 659                         }
 660
 661                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
 662                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
 663                              (newflags & HIDDEV_FLAG_UREF) == 0))
 664                                 break;
 665
 666                         list->flags = newflags;
 667
 668                         r = 0;
 669                         break;
 670                 }
 671
 672         case HIDIOCGSTRING:
 673                 r = hiddev_ioctl_string(hiddev, cmd, user_arg);
 674                 break;
 675
 676         case HIDIOCINITREPORT:
 677                 usbhid_init_reports(hid);
 678                 r = 0;
 679                 break;
 680
 681         case HIDIOCGREPORT:
 682                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 683                         r = -EFAULT;
 684                         break;
 685                 }
 686
 687                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
 688                         break;
 689
 690                 report = hiddev_lookup_report(hid, &rinfo);
 691                 if (report == NULL)
 692                         break;
 693
 694                 usbhid_submit_report(hid, report, USB_DIR_IN);
 695                 usbhid_wait_io(hid);
 696
 697                 r = 0;
 698                 break;
 699
 700         case HIDIOCSREPORT:
 701                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 702                         r = -EFAULT;
 703                         break;
 704                 }
 705
 706                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
 707                         break;
 708
 709                 report = hiddev_lookup_report(hid, &rinfo);
 710                 if (report == NULL)
 711                         break;
 712
 713                 usbhid_submit_report(hid, report, USB_DIR_OUT);
 714                 usbhid_wait_io(hid);
 715
 716                 r = 0;
 717                 break;
 718
 719         case HIDIOCGREPORTINFO:
 720                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 721                         r = -EFAULT;
 722                         break;
 723                 }
 724
 725                 report = hiddev_lookup_report(hid, &rinfo);
 726                 if (report == NULL)
 727                         break;
 728
 729                 rinfo.num_fields = report->maxfield;
 730
 731                 r = copy_to_user(user_arg, &rinfo, sizeof(rinfo)) ?
 732                         -EFAULT : 0;
 733                 break;
 734
 735         case HIDIOCGFIELDINFO:
 736                 if (copy_from_user(&finfo, user_arg, sizeof(finfo))) {
 737                         r = -EFAULT;
 738                         break;
 739                 }
 740
 741                 rinfo.report_type = finfo.report_type;
 742                 rinfo.report_id = finfo.report_id;
 743
 744                 report = hiddev_lookup_report(hid, &rinfo);
 745                 if (report == NULL)
 746                         break;
 747
 748                 if (finfo.field_index >= report->maxfield)
 749                         break;
 750
 751                 field = report->field[finfo.field_index];
 752                 memset(&finfo, 0, sizeof(finfo));
 753                 finfo.report_type = rinfo.report_type;
 754                 finfo.report_id = rinfo.report_id;
 755                 finfo.field_index = field->report_count - 1;
 756                 finfo.maxusage = field->maxusage;
 757                 finfo.flags = field->flags;
 758                 finfo.physical = field->physical;
 759                 finfo.logical = field->logical;
 760                 finfo.application = field->application;
 761                 finfo.logical_minimum = field->logical_minimum;
 762                 finfo.logical_maximum = field->logical_maximum;
 763                 finfo.physical_minimum = field->physical_minimum;
 764                 finfo.physical_maximum = field->physical_maximum;
 765                 finfo.unit_exponent = field->unit_exponent;
 766                 finfo.unit = field->unit;
 767
 768                 r = copy_to_user(user_arg, &finfo, sizeof(finfo)) ?
 769                         -EFAULT : 0;
 770                 break;
 771
 772         case HIDIOCGUCODE:
 773                 /* fall through */
 774         case HIDIOCGUSAGE:
 775         case HIDIOCSUSAGE:
 776         case HIDIOCGUSAGES:
 777         case HIDIOCSUSAGES:
 778         case HIDIOCGCOLLECTIONINDEX:
 779                 r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
 780                 break;
 781
 782         case HIDIOCGCOLLECTIONINFO:
 783                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo))) {
 784                         r = -EFAULT;
 785                         break;
 786                 }
 787
 788                 if (cinfo.index >= hid->maxcollection)
 789                         break;
 790
 791                 cinfo.type = hid->collection[cinfo.index].type;
 792                 cinfo.usage = hid->collection[cinfo.index].usage;
 793                 cinfo.level = hid->collection[cinfo.index].level;
 794
 795                 r = copy_to_user(user_arg, &cinfo, sizeof(cinfo)) ?
 796                         -EFAULT : 0;
 797                 break;
 798
 799         default:
 800                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
 801                         break;
 802
 803                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
 804                         int len;
 805
 806                         if (!hid->name) {
 807                                 r = 0;
 808                                 break;
 809                         }
 810
 811                         len = strlen(hid->name) + 1;
 812                         if (len > _IOC_SIZE(cmd))
 813                                  len = _IOC_SIZE(cmd);
 814                         r = copy_to_user(user_arg, hid->name, len) ?
 815                                 -EFAULT : len;
 816                         break;
 817                 }
 818
 819                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
 820                         int len;
 821
 822                         if (!hid->phys) {
 823                                 r = 0;
 824                                 break;
 825                         }
 826
 827                         len = strlen(hid->phys) + 1;
 828                         if (len > _IOC_SIZE(cmd))
 829                                 len = _IOC_SIZE(cmd);
 830                         r = copy_to_user(user_arg, hid->phys, len) ?
 831                                 -EFAULT : len;
 832                         break;
 833                 }
 834         }
 835
 836 ret_unlock:
 837         mutex_unlock(&hiddev->existancelock);
 838         return r;
 839 }
 840
 841 #ifdef CONFIG_COMPAT
 842 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 843 {
 844         return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
 845 }
 846 #endif
 847
 848 static const struct file_operations hiddev_fops = {
 849         .owner =        THIS_MODULE,
 850         .read =         hiddev_read,
 851         .write =        hiddev_write,
 852         .poll =         hiddev_poll,
 853         .open =         hiddev_open,
 854         .release =      hiddev_release,
 855         .unlocked_ioctl =       hiddev_ioctl,
 856         .fasync =       hiddev_fasync,
 857 #ifdef CONFIG_COMPAT
 858         .compat_ioctl   = hiddev_compat_ioctl,
 859 #endif
 860         .llseek         = noop_llseek,
 861 };
 862
 863 static char *hiddev_devnode(struct device *dev, mode_t *mode)
 864 {
 865         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
 866 }
 867
 868 static struct usb_class_driver hiddev_class = {
 869         .name =         "hiddev%d",
 870         .devnode =      hiddev_devnode,
 871         .fops =         &hiddev_fops,
 872         .minor_base =   HIDDEV_MINOR_BASE,
 873 };
 874
 875 /*
 876  * This is where hid.c calls us to connect a hid device to the hiddev driver
 877  */
 878 int hiddev_connect(struct hid_device *hid, unsigned int force)
 879 {
 880         struct hiddev *hiddev;
 881         struct usbhid_device *usbhid = hid->driver_data;
 882         int retval;
 883
 884         if (!force) {
 885                 unsigned int i;
 886                 for (i = 0; i < hid->maxcollection; i++)
 887                         if (hid->collection[i].type ==
 888                             HID_COLLECTION_APPLICATION &&
 889                             !IS_INPUT_APPLICATION(hid->collection[i].usage))
 890                                 break;
 891
 892                 if (i == hid->maxcollection)
 893                         return -1;
 894         }
 895
 896         if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
 897                 return -1;
 898
 899         init_waitqueue_head(&hiddev->wait);
 900         INIT_LIST_HEAD(&hiddev->list);
 901         spin_lock_init(&hiddev->list_lock);
 902         mutex_init(&hiddev->existancelock);
 903         hid->hiddev = hiddev;
 904         hiddev->hid = hid;
 905         hiddev->exist = 1;
 906         retval = usb_register_dev(usbhid->intf, &hiddev_class);
 907         if (retval) {
 908                 hid_err(hid, "Not able to get a minor for this device\n");
 909                 hid->hiddev = NULL;
 910                 kfree(hiddev);
 911                 return -1;
 912         }
 913         return 0;
 914 }
 915
 916 /*
 917  * This is where hid.c calls us to disconnect a hiddev device from the
 918  * corresponding hid device (usually because the usb device has disconnected)
 919  */
 920 static struct usb_class_driver hiddev_class;
 921 void hiddev_disconnect(struct hid_device *hid)
 922 {
 923         struct hiddev *hiddev = hid->hiddev;
 924         struct usbhid_device *usbhid = hid->driver_data;
 925
 926         mutex_lock(&hiddev->existancelock);
 927         hiddev->exist = 0;
 928         mutex_unlock(&hiddev->existancelock);
 929
 930         usb_deregister_dev(usbhid->intf, &hiddev_class);
 931
 932         if (hiddev->open) {
 933                 usbhid_close(hiddev->hid);
 934                 wake_up_interruptible(&hiddev->wait);
 935         } else {
 936                 kfree(hiddev);
 937         }
 938 }