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 <linux/vmalloc.h>
  38 #include <linux/nospec.h>
  39 #include "usbhid.h"
  40
  41 #ifdef CONFIG_USB_DYNAMIC_MINORS
  42 #define HIDDEV_MINOR_BASE       0
  43 #define HIDDEV_MINORS           256
  44 #else
  45 #define HIDDEV_MINOR_BASE       96
  46 #define HIDDEV_MINORS           16
  47 #endif
  48 #define HIDDEV_BUFFER_SIZE      2048
  49
  50 struct hiddev {
  51         int exist;
  52         int open;
  53         struct mutex existancelock;
  54         wait_queue_head_t wait;
  55         struct hid_device *hid;
  56         struct list_head list;
  57         spinlock_t list_lock;
  58 };
  59
  60 struct hiddev_list {
  61         struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
  62         int head;
  63         int tail;
  64         unsigned flags;
  65         struct fasync_struct *fasync;
  66         struct hiddev *hiddev;
  67         struct list_head node;
  68         struct mutex thread_lock;
  69 };
  70
  71 /*
  72  * Find a report, given the report's type and ID.  The ID can be specified
  73  * indirectly by REPORT_ID_FIRST (which returns the first report of the given
  74  * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
  75  * given type which follows old_id.
  76  */
  77 static struct hid_report *
  78 hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
  79 {
  80         unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
  81         unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK;
  82         struct hid_report_enum *report_enum;
  83         struct hid_report *report;
  84         struct list_head *list;
  85
  86         if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
  87             rinfo->report_type > HID_REPORT_TYPE_MAX)
  88                 return NULL;
  89
  90         report_enum = hid->report_enum +
  91                 (rinfo->report_type - HID_REPORT_TYPE_MIN);
  92
  93         switch (flags) {
  94         case 0: /* Nothing to do -- report_id is already set correctly */
  95                 break;
  96
  97         case HID_REPORT_ID_FIRST:
  98                 if (list_empty(&report_enum->report_list))
  99                         return NULL;
 100
 101                 list = report_enum->report_list.next;
 102                 report = list_entry(list, struct hid_report, list);
 103                 rinfo->report_id = report->id;
 104                 break;
 105
 106         case HID_REPORT_ID_NEXT:
 107                 report = report_enum->report_id_hash[rid];
 108                 if (!report)
 109                         return NULL;
 110
 111                 list = report->list.next;
 112                 if (list == &report_enum->report_list)
 113                         return NULL;
 114
 115                 report = list_entry(list, struct hid_report, list);
 116                 rinfo->report_id = report->id;
 117                 break;
 118
 119         default:
 120                 return NULL;
 121         }
 122
 123         return report_enum->report_id_hash[rinfo->report_id];
 124 }
 125
 126 /*
 127  * Perform an exhaustive search of the report table for a usage, given its
 128  * type and usage id.
 129  */
 130 static struct hid_field *
 131 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
 132 {
 133         int i, j;
 134         struct hid_report *report;
 135         struct hid_report_enum *report_enum;
 136         struct hid_field *field;
 137
 138         if (uref->report_type < HID_REPORT_TYPE_MIN ||
 139             uref->report_type > HID_REPORT_TYPE_MAX)
 140                 return NULL;
 141
 142         report_enum = hid->report_enum +
 143                 (uref->report_type - HID_REPORT_TYPE_MIN);
 144
 145         list_for_each_entry(report, &report_enum->report_list, list) {
 146                 for (i = 0; i < report->maxfield; i++) {
 147                         field = report->field[i];
 148                         for (j = 0; j < field->maxusage; j++) {
 149                                 if (field->usage[j].hid == uref->usage_code) {
 150                                         uref->report_id = report->id;
 151                                         uref->field_index = i;
 152                                         uref->usage_index = j;
 153                                         return field;
 154                                 }
 155                         }
 156                 }
 157         }
 158
 159         return NULL;
 160 }
 161
 162 static void hiddev_send_event(struct hid_device *hid,
 163                               struct hiddev_usage_ref *uref)
 164 {
 165         struct hiddev *hiddev = hid->hiddev;
 166         struct hiddev_list *list;
 167         unsigned long flags;
 168
 169         spin_lock_irqsave(&hiddev->list_lock, flags);
 170         list_for_each_entry(list, &hiddev->list, node) {
 171                 if (uref->field_index != HID_FIELD_INDEX_NONE ||
 172                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 173                         list->buffer[list->head] = *uref;
 174                         list->head = (list->head + 1) &
 175                                 (HIDDEV_BUFFER_SIZE - 1);
 176                         kill_fasync(&list->fasync, SIGIO, POLL_IN);
 177                 }
 178         }
 179         spin_unlock_irqrestore(&hiddev->list_lock, flags);
 180
 181         wake_up_interruptible(&hiddev->wait);
 182 }
 183
 184 /*
 185  * This is where hid.c calls into hiddev to pass an event that occurred over
 186  * the interrupt pipe
 187  */
 188 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
 189                       struct hid_usage *usage, __s32 value)
 190 {
 191         unsigned type = field->report_type;
 192         struct hiddev_usage_ref uref;
 193
 194         uref.report_type =
 195           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
 196           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
 197            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
 198         uref.report_id = field->report->id;
 199         uref.field_index = field->index;
 200         uref.usage_index = (usage - field->usage);
 201         uref.usage_code = usage->hid;
 202         uref.value = value;
 203
 204         hiddev_send_event(hid, &uref);
 205 }
 206 EXPORT_SYMBOL_GPL(hiddev_hid_event);
 207
 208 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
 209 {
 210         unsigned type = report->type;
 211         struct hiddev_usage_ref uref;
 212
 213         memset(&uref, 0, sizeof(uref));
 214         uref.report_type =
 215           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
 216           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
 217            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
 218         uref.report_id = report->id;
 219         uref.field_index = HID_FIELD_INDEX_NONE;
 220
 221         hiddev_send_event(hid, &uref);
 222 }
 223
 224 /*
 225  * fasync file op
 226  */
 227 static int hiddev_fasync(int fd, struct file *file, int on)
 228 {
 229         struct hiddev_list *list = file->private_data;
 230
 231         return fasync_helper(fd, file, on, &list->fasync);
 232 }
 233
 234
 235 /*
 236  * release file op
 237  */
 238 static int hiddev_release(struct inode * inode, struct file * file)
 239 {
 240         struct hiddev_list *list = file->private_data;
 241         unsigned long flags;
 242
 243         spin_lock_irqsave(&list->hiddev->list_lock, flags);
 244         list_del(&list->node);
 245         spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
 246
 247         mutex_lock(&list->hiddev->existancelock);
 248         if (!--list->hiddev->open) {
 249                 if (list->hiddev->exist) {
 250                         usbhid_close(list->hiddev->hid);
 251                         usbhid_put_power(list->hiddev->hid);
 252                 } else {
 253                         mutex_unlock(&list->hiddev->existancelock);
 254                         kfree(list->hiddev);
 255                         vfree(list);
 256                         return 0;
 257                 }
 258         }
 259
 260         mutex_unlock(&list->hiddev->existancelock);
 261         vfree(list);
 262
 263         return 0;
 264 }
 265
 266 /*
 267  * open file op
 268  */
 269 static int hiddev_open(struct inode *inode, struct file *file)
 270 {
 271         struct hiddev_list *list;
 272         struct usb_interface *intf;
 273         struct hid_device *hid;
 274         struct hiddev *hiddev;
 275         int res;
 276
 277         intf = usbhid_find_interface(iminor(inode));
 278         if (!intf)
 279                 return -ENODEV;
 280         hid = usb_get_intfdata(intf);
 281         hiddev = hid->hiddev;
 282
 283         if (!(list = vzalloc(sizeof(struct hiddev_list))))
 284                 return -ENOMEM;
 285         mutex_init(&list->thread_lock);
 286         list->hiddev = hiddev;
 287         file->private_data = list;
 288
 289         /*
 290          * no need for locking because the USB major number
 291          * is shared which usbcore guards against disconnect
 292          */
 293         if (list->hiddev->exist) {
 294                 if (!list->hiddev->open++) {
 295                         res = usbhid_open(hiddev->hid);
 296                         if (res < 0) {
 297                                 res = -EIO;
 298                                 goto bail;
 299                         }
 300                 }
 301         } else {
 302                 res = -ENODEV;
 303                 goto bail;
 304         }
 305
 306         spin_lock_irq(&list->hiddev->list_lock);
 307         list_add_tail(&list->node, &hiddev->list);
 308         spin_unlock_irq(&list->hiddev->list_lock);
 309
 310         mutex_lock(&hiddev->existancelock);
 311         /*
 312          * recheck exist with existance lock held to
 313          * avoid opening a disconnected device
 314          */
 315         if (!list->hiddev->exist) {
 316                 res = -ENODEV;
 317                 goto bail_unlock;
 318         }
 319         if (!list->hiddev->open++)
 320                 if (list->hiddev->exist) {
 321                         struct hid_device *hid = hiddev->hid;
 322                         res = usbhid_get_power(hid);
 323                         if (res < 0) {
 324                                 res = -EIO;
 325                                 goto bail_unlock;
 326                         }
 327                         usbhid_open(hid);
 328                 }
 329         mutex_unlock(&hiddev->existancelock);
 330         return 0;
 331 bail_unlock:
 332         mutex_unlock(&hiddev->existancelock);
 333
 334         spin_lock_irq(&list->hiddev->list_lock);
 335         list_del(&list->node);
 336         spin_unlock_irq(&list->hiddev->list_lock);
 337 bail:
 338         file->private_data = NULL;
 339         vfree(list);
 340         return res;
 341 }
 342
 343 /*
 344  * "write" file op
 345  */
 346 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
 347 {
 348         return -EINVAL;
 349 }
 350
 351 /*
 352  * "read" file op
 353  */
 354 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
 355 {
 356         DEFINE_WAIT(wait);
 357         struct hiddev_list *list = file->private_data;
 358         int event_size;
 359         int retval;
 360
 361         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
 362                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
 363
 364         if (count < event_size)
 365                 return 0;
 366
 367         /* lock against other threads */
 368         retval = mutex_lock_interruptible(&list->thread_lock);
 369         if (retval)
 370                 return -ERESTARTSYS;
 371
 372         while (retval == 0) {
 373                 if (list->head == list->tail) {
 374                         prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);
 375
 376                         while (list->head == list->tail) {
 377                                 if (signal_pending(current)) {
 378                                         retval = -ERESTARTSYS;
 379                                         break;
 380                                 }
 381                                 if (!list->hiddev->exist) {
 382                                         retval = -EIO;
 383                                         break;
 384                                 }
 385                                 if (file->f_flags & O_NONBLOCK) {
 386                                         retval = -EAGAIN;
 387                                         break;
 388                                 }
 389
 390                                 /* let O_NONBLOCK tasks run */
 391                                 mutex_unlock(&list->thread_lock);
 392                                 schedule();
 393                                 if (mutex_lock_interruptible(&list->thread_lock)) {
 394                                         finish_wait(&list->hiddev->wait, &wait);
 395                                         return -EINTR;
 396                                 }
 397                                 set_current_state(TASK_INTERRUPTIBLE);
 398                         }
 399                         finish_wait(&list->hiddev->wait, &wait);
 400
 401                 }
 402
 403                 if (retval) {
 404                         mutex_unlock(&list->thread_lock);
 405                         return retval;
 406                 }
 407
 408
 409                 while (list->head != list->tail &&
 410                        retval + event_size <= count) {
 411                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
 412                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
 413                                         struct hiddev_event event;
 414
 415                                         event.hid = list->buffer[list->tail].usage_code;
 416                                         event.value = list->buffer[list->tail].value;
 417                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {
 418                                                 mutex_unlock(&list->thread_lock);
 419                                                 return -EFAULT;
 420                                         }
 421                                         retval += sizeof(struct hiddev_event);
 422                                 }
 423                         } else {
 424                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
 425                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 426
 427                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {
 428                                                 mutex_unlock(&list->thread_lock);
 429                                                 return -EFAULT;
 430                                         }
 431                                         retval += sizeof(struct hiddev_usage_ref);
 432                                 }
 433                         }
 434                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
 435                 }
 436
 437         }
 438         mutex_unlock(&list->thread_lock);
 439
 440         return retval;
 441 }
 442
 443 /*
 444  * "poll" file op
 445  * No kernel lock - fine
 446  */
 447 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
 448 {
 449         struct hiddev_list *list = file->private_data;
 450
 451         poll_wait(file, &list->hiddev->wait, wait);
 452         if (list->head != list->tail)
 453                 return POLLIN | POLLRDNORM;
 454         if (!list->hiddev->exist)
 455                 return POLLERR | POLLHUP;
 456         return 0;
 457 }
 458
 459 /*
 460  * "ioctl" file op
 461  */
 462 static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 463 {
 464         struct hid_device *hid = hiddev->hid;
 465         struct hiddev_report_info rinfo;
 466         struct hiddev_usage_ref_multi *uref_multi = NULL;
 467         struct hiddev_usage_ref *uref;
 468         struct hid_report *report;
 469         struct hid_field *field;
 470         int i;
 471
 472         uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
 473         if (!uref_multi)
 474                 return -ENOMEM;
 475         uref = &uref_multi->uref;
 476         if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
 477                 if (copy_from_user(uref_multi, user_arg,
 478                                    sizeof(*uref_multi)))
 479                         goto fault;
 480         } else {
 481                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
 482                         goto fault;
 483         }
 484
 485         switch (cmd) {
 486         case HIDIOCGUCODE:
 487                 rinfo.report_type = uref->report_type;
 488                 rinfo.report_id = uref->report_id;
 489                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 490                         goto inval;
 491
 492                 if (uref->field_index >= report->maxfield)
 493                         goto inval;
 494                 uref->field_index = array_index_nospec(uref->field_index,
 495                                                        report->maxfield);
 496
 497                 field = report->field[uref->field_index];
 498                 if (uref->usage_index >= field->maxusage)
 499                         goto inval;
 500                 uref->usage_index = array_index_nospec(uref->usage_index,
 501                                                        field->maxusage);
 502
 503                 uref->usage_code = field->usage[uref->usage_index].hid;
 504
 505                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
 506                         goto fault;
 507
 508                 goto goodreturn;
 509
 510         default:
 511                 if (cmd != HIDIOCGUSAGE &&
 512                     cmd != HIDIOCGUSAGES &&
 513                     uref->report_type == HID_REPORT_TYPE_INPUT)
 514                         goto inval;
 515
 516                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
 517                         field = hiddev_lookup_usage(hid, uref);
 518                         if (field == NULL)
 519                                 goto inval;
 520                 } else {
 521                         rinfo.report_type = uref->report_type;
 522                         rinfo.report_id = uref->report_id;
 523                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 524                                 goto inval;
 525
 526                         if (uref->field_index >= report->maxfield)
 527                                 goto inval;
 528                         uref->field_index = array_index_nospec(uref->field_index,
 529                                                                report->maxfield);
 530
 531                         field = report->field[uref->field_index];
 532
 533                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
 534                                 if (uref->usage_index >= field->maxusage)
 535                                         goto inval;
 536                                 uref->usage_index =
 537                                         array_index_nospec(uref->usage_index,
 538                                                            field->maxusage);
 539                         } else if (uref->usage_index >= field->report_count)
 540                                 goto inval;
 541                 }
 542
 543                 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
 544                         if (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
 545                             uref->usage_index + uref_multi->num_values >
 546                             field->report_count)
 547                                 goto inval;
 548
 549                         uref->usage_index =
 550                                 array_index_nospec(uref->usage_index,
 551                                                    field->report_count -
 552                                                    uref_multi->num_values);
 553                 }
 554
 555                 switch (cmd) {
 556                 case HIDIOCGUSAGE:
 557                         if (uref->usage_index >= field->report_count)
 558                                 goto inval;
 559                         uref->value = field->value[uref->usage_index];
 560                         if (copy_to_user(user_arg, uref, sizeof(*uref)))
 561                                 goto fault;
 562                         goto goodreturn;
 563
 564                 case HIDIOCSUSAGE:
 565                         if (uref->usage_index >= field->report_count)
 566                                 goto inval;
 567                         field->value[uref->usage_index] = uref->value;
 568                         goto goodreturn;
 569
 570                 case HIDIOCGCOLLECTIONINDEX:
 571                         i = field->usage[uref->usage_index].collection_index;
 572                         kfree(uref_multi);
 573                         return i;
 574                 case HIDIOCGUSAGES:
 575                         for (i = 0; i < uref_multi->num_values; i++)
 576                                 uref_multi->values[i] =
 577                                     field->value[uref->usage_index + i];
 578                         if (copy_to_user(user_arg, uref_multi,
 579                                          sizeof(*uref_multi)))
 580                                 goto fault;
 581                         goto goodreturn;
 582                 case HIDIOCSUSAGES:
 583                         for (i = 0; i < uref_multi->num_values; i++)
 584                                 field->value[uref->usage_index + i] =
 585                                     uref_multi->values[i];
 586                         goto goodreturn;
 587                 }
 588
 589 goodreturn:
 590                 kfree(uref_multi);
 591                 return 0;
 592 fault:
 593                 kfree(uref_multi);
 594                 return -EFAULT;
 595 inval:
 596                 kfree(uref_multi);
 597                 return -EINVAL;
 598         }
 599 }
 600
 601 static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 602 {
 603         struct hid_device *hid = hiddev->hid;
 604         struct usb_device *dev = hid_to_usb_dev(hid);
 605         int idx, len;
 606         char *buf;
 607
 608         if (get_user(idx, (int __user *)user_arg))
 609                 return -EFAULT;
 610
 611         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
 612                 return -ENOMEM;
 613
 614         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
 615                 kfree(buf);
 616                 return -EINVAL;
 617         }
 618
 619         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
 620                 kfree(buf);
 621                 return -EFAULT;
 622         }
 623
 624         kfree(buf);
 625
 626         return len;
 627 }
 628
 629 static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 630 {
 631         struct hiddev_list *list = file->private_data;
 632         struct hiddev *hiddev = list->hiddev;
 633         struct hid_device *hid;
 634         struct hiddev_collection_info cinfo;
 635         struct hiddev_report_info rinfo;
 636         struct hiddev_field_info finfo;
 637         struct hiddev_devinfo dinfo;
 638         struct hid_report *report;
 639         struct hid_field *field;
 640         void __user *user_arg = (void __user *)arg;
 641         int i, r = -EINVAL;
 642
 643         /* Called without BKL by compat methods so no BKL taken */
 644
 645         mutex_lock(&hiddev->existancelock);
 646         if (!hiddev->exist) {
 647                 r = -ENODEV;
 648                 goto ret_unlock;
 649         }
 650
 651         hid = hiddev->hid;
 652
 653         switch (cmd) {
 654
 655         case HIDIOCGVERSION:
 656                 r = put_user(HID_VERSION, (int __user *)arg) ?
 657                         -EFAULT : 0;
 658                 break;
 659
 660         case HIDIOCAPPLICATION:
 661                 if (arg >= hid->maxapplication)
 662                         break;
 663
 664                 for (i = 0; i < hid->maxcollection; i++)
 665                         if (hid->collection[i].type ==
 666                             HID_COLLECTION_APPLICATION && arg-- == 0)
 667                                 break;
 668
 669                 if (i < hid->maxcollection)
 670                         r = hid->collection[i].usage;
 671                 break;
 672
 673         case HIDIOCGDEVINFO:
 674                 {
 675                         struct usb_device *dev = hid_to_usb_dev(hid);
 676                         struct usbhid_device *usbhid = hid->driver_data;
 677
 678                         memset(&dinfo, 0, sizeof(dinfo));
 679
 680                         dinfo.bustype = BUS_USB;
 681                         dinfo.busnum = dev->bus->busnum;
 682                         dinfo.devnum = dev->devnum;
 683                         dinfo.ifnum = usbhid->ifnum;
 684                         dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
 685                         dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
 686                         dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
 687                         dinfo.num_applications = hid->maxapplication;
 688
 689                         r = copy_to_user(user_arg, &dinfo, sizeof(dinfo)) ?
 690                                 -EFAULT : 0;
 691                         break;
 692                 }
 693
 694         case HIDIOCGFLAG:
 695                 r = put_user(list->flags, (int __user *)arg) ?
 696                         -EFAULT : 0;
 697                 break;
 698
 699         case HIDIOCSFLAG:
 700                 {
 701                         int newflags;
 702
 703                         if (get_user(newflags, (int __user *)arg)) {
 704                                 r = -EFAULT;
 705                                 break;
 706                         }
 707
 708                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
 709                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
 710                              (newflags & HIDDEV_FLAG_UREF) == 0))
 711                                 break;
 712
 713                         list->flags = newflags;
 714
 715                         r = 0;
 716                         break;
 717                 }
 718
 719         case HIDIOCGSTRING:
 720                 r = hiddev_ioctl_string(hiddev, cmd, user_arg);
 721                 break;
 722
 723         case HIDIOCINITREPORT:
 724                 usbhid_init_reports(hid);
 725                 r = 0;
 726                 break;
 727
 728         case HIDIOCGREPORT:
 729                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 730                         r = -EFAULT;
 731                         break;
 732                 }
 733
 734                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
 735                         break;
 736
 737                 report = hiddev_lookup_report(hid, &rinfo);
 738                 if (report == NULL)
 739                         break;
 740
 741                 hid_hw_request(hid, report, HID_REQ_GET_REPORT);
 742                 hid_hw_wait(hid);
 743
 744                 r = 0;
 745                 break;
 746
 747         case HIDIOCSREPORT:
 748                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 749                         r = -EFAULT;
 750                         break;
 751                 }
 752
 753                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
 754                         break;
 755
 756                 report = hiddev_lookup_report(hid, &rinfo);
 757                 if (report == NULL)
 758                         break;
 759
 760                 hid_hw_request(hid, report, HID_REQ_SET_REPORT);
 761                 hid_hw_wait(hid);
 762
 763                 r = 0;
 764                 break;
 765
 766         case HIDIOCGREPORTINFO:
 767                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 768                         r = -EFAULT;
 769                         break;
 770                 }
 771
 772                 report = hiddev_lookup_report(hid, &rinfo);
 773                 if (report == NULL)
 774                         break;
 775
 776                 rinfo.num_fields = report->maxfield;
 777
 778                 r = copy_to_user(user_arg, &rinfo, sizeof(rinfo)) ?
 779                         -EFAULT : 0;
 780                 break;
 781
 782         case HIDIOCGFIELDINFO:
 783                 if (copy_from_user(&finfo, user_arg, sizeof(finfo))) {
 784                         r = -EFAULT;
 785                         break;
 786                 }
 787
 788                 rinfo.report_type = finfo.report_type;
 789                 rinfo.report_id = finfo.report_id;
 790
 791                 report = hiddev_lookup_report(hid, &rinfo);
 792                 if (report == NULL)
 793                         break;
 794
 795                 if (finfo.field_index >= report->maxfield)
 796                         break;
 797                 finfo.field_index = array_index_nospec(finfo.field_index,
 798                                                        report->maxfield);
 799
 800                 field = report->field[finfo.field_index];
 801                 memset(&finfo, 0, sizeof(finfo));
 802                 finfo.report_type = rinfo.report_type;
 803                 finfo.report_id = rinfo.report_id;
 804                 finfo.field_index = field->report_count - 1;
 805                 finfo.maxusage = field->maxusage;
 806                 finfo.flags = field->flags;
 807                 finfo.physical = field->physical;
 808                 finfo.logical = field->logical;
 809                 finfo.application = field->application;
 810                 finfo.logical_minimum = field->logical_minimum;
 811                 finfo.logical_maximum = field->logical_maximum;
 812                 finfo.physical_minimum = field->physical_minimum;
 813                 finfo.physical_maximum = field->physical_maximum;
 814                 finfo.unit_exponent = field->unit_exponent;
 815                 finfo.unit = field->unit;
 816
 817                 r = copy_to_user(user_arg, &finfo, sizeof(finfo)) ?
 818                         -EFAULT : 0;
 819                 break;
 820
 821         case HIDIOCGUCODE:
 822                 /* fall through */
 823         case HIDIOCGUSAGE:
 824         case HIDIOCSUSAGE:
 825         case HIDIOCGUSAGES:
 826         case HIDIOCSUSAGES:
 827         case HIDIOCGCOLLECTIONINDEX:
 828                 r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
 829                 break;
 830
 831         case HIDIOCGCOLLECTIONINFO:
 832                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo))) {
 833                         r = -EFAULT;
 834                         break;
 835                 }
 836
 837                 if (cinfo.index >= hid->maxcollection)
 838                         break;
 839                 cinfo.index = array_index_nospec(cinfo.index,
 840                                                  hid->maxcollection);
 841
 842                 cinfo.type = hid->collection[cinfo.index].type;
 843                 cinfo.usage = hid->collection[cinfo.index].usage;
 844                 cinfo.level = hid->collection[cinfo.index].level;
 845
 846                 r = copy_to_user(user_arg, &cinfo, sizeof(cinfo)) ?
 847                         -EFAULT : 0;
 848                 break;
 849
 850         default:
 851                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
 852                         break;
 853
 854                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
 855                         int len = strlen(hid->name) + 1;
 856                         if (len > _IOC_SIZE(cmd))
 857                                  len = _IOC_SIZE(cmd);
 858                         r = copy_to_user(user_arg, hid->name, len) ?
 859                                 -EFAULT : len;
 860                         break;
 861                 }
 862
 863                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
 864                         int len = strlen(hid->phys) + 1;
 865                         if (len > _IOC_SIZE(cmd))
 866                                 len = _IOC_SIZE(cmd);
 867                         r = copy_to_user(user_arg, hid->phys, len) ?
 868                                 -EFAULT : len;
 869                         break;
 870                 }
 871         }
 872
 873 ret_unlock:
 874         mutex_unlock(&hiddev->existancelock);
 875         return r;
 876 }
 877
 878 #ifdef CONFIG_COMPAT
 879 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 880 {
 881         return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
 882 }
 883 #endif
 884
 885 static const struct file_operations hiddev_fops = {
 886         .owner =        THIS_MODULE,
 887         .read =         hiddev_read,
 888         .write =        hiddev_write,
 889         .poll =         hiddev_poll,
 890         .open =         hiddev_open,
 891         .release =      hiddev_release,
 892         .unlocked_ioctl =       hiddev_ioctl,
 893         .fasync =       hiddev_fasync,
 894 #ifdef CONFIG_COMPAT
 895         .compat_ioctl   = hiddev_compat_ioctl,
 896 #endif
 897         .llseek         = noop_llseek,
 898 };
 899
 900 static char *hiddev_devnode(struct device *dev, umode_t *mode)
 901 {
 902         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
 903 }
 904
 905 static struct usb_class_driver hiddev_class = {
 906         .name =         "hiddev%d",
 907         .devnode =      hiddev_devnode,
 908         .fops =         &hiddev_fops,
 909         .minor_base =   HIDDEV_MINOR_BASE,
 910 };
 911
 912 /*
 913  * This is where hid.c calls us to connect a hid device to the hiddev driver
 914  */
 915 int hiddev_connect(struct hid_device *hid, unsigned int force)
 916 {
 917         struct hiddev *hiddev;
 918         struct usbhid_device *usbhid = hid->driver_data;
 919         int retval;
 920
 921         if (!force) {
 922                 unsigned int i;
 923                 for (i = 0; i < hid->maxcollection; i++)
 924                         if (hid->collection[i].type ==
 925                             HID_COLLECTION_APPLICATION &&
 926                             !IS_INPUT_APPLICATION(hid->collection[i].usage))
 927                                 break;
 928
 929                 if (i == hid->maxcollection)
 930                         return -1;
 931         }
 932
 933         if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
 934                 return -1;
 935
 936         init_waitqueue_head(&hiddev->wait);
 937         INIT_LIST_HEAD(&hiddev->list);
 938         spin_lock_init(&hiddev->list_lock);
 939         mutex_init(&hiddev->existancelock);
 940         hid->hiddev = hiddev;
 941         hiddev->hid = hid;
 942         hiddev->exist = 1;
 943         retval = usb_register_dev(usbhid->intf, &hiddev_class);
 944         if (retval) {
 945                 hid_err(hid, "Not able to get a minor for this device\n");
 946                 hid->hiddev = NULL;
 947                 kfree(hiddev);
 948                 return -1;
 949         }
 950         return 0;
 951 }
 952
 953 /*
 954  * This is where hid.c calls us to disconnect a hiddev device from the
 955  * corresponding hid device (usually because the usb device has disconnected)
 956  */
 957 static struct usb_class_driver hiddev_class;
 958 void hiddev_disconnect(struct hid_device *hid)
 959 {
 960         struct hiddev *hiddev = hid->hiddev;
 961         struct usbhid_device *usbhid = hid->driver_data;
 962
 963         usb_deregister_dev(usbhid->intf, &hiddev_class);
 964
 965         mutex_lock(&hiddev->existancelock);
 966         hiddev->exist = 0;
 967
 968         if (hiddev->open) {
 969                 usbhid_close(hiddev->hid);
 970                 wake_up_interruptible(&hiddev->wait);
 971                 mutex_unlock(&hiddev->existancelock);
 972         } else {
 973                 mutex_unlock(&hiddev->existancelock);
 974                 kfree(hiddev);
 975         }
 976 }