drivers/hid/usbhid/hiddev.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Copyright (c) 2001 Paul Stewart
   4  *  Copyright (c) 2001 Vojtech Pavlik
   5  *
   6  *  HID char devices, giving access to raw HID device events.
   7  */
   8
   9 /*
  10  *
  11  * Should you need to contact me, the author, you can do so either by
  12  * e-mail - mail your message to Paul Stewart <stewart@wetlogic.net>
  13  */
  14
  15 #include <linux/poll.h>
  16 #include <linux/slab.h>
  17 #include <linux/sched/signal.h>
  18 #include <linux/module.h>
  19 #include <linux/init.h>
  20 #include <linux/input.h>
  21 #include <linux/usb.h>
  22 #include <linux/hid.h>
  23 #include <linux/hiddev.h>
  24 #include <linux/compat.h>
  25 #include <linux/vmalloc.h>
  26 #include <linux/nospec.h>
  27 #include "usbhid.h"
  28
  29 #ifdef CONFIG_USB_DYNAMIC_MINORS
  30 #define HIDDEV_MINOR_BASE       0
  31 #define HIDDEV_MINORS           256
  32 #else
  33 #define HIDDEV_MINOR_BASE       96
  34 #define HIDDEV_MINORS           16
  35 #endif
  36 #define HIDDEV_BUFFER_SIZE      2048
  37
  38 struct hiddev_list {
  39         struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
  40         int head;
  41         int tail;
  42         unsigned flags;
  43         struct fasync_struct *fasync;
  44         struct hiddev *hiddev;
  45         struct list_head node;
  46         struct mutex thread_lock;
  47 };
  48
  49 /*
  50  * Find a report, given the report's type and ID.  The ID can be specified
  51  * indirectly by REPORT_ID_FIRST (which returns the first report of the given
  52  * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
  53  * given type which follows old_id.
  54  */
  55 static struct hid_report *
  56 hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
  57 {
  58         unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
  59         unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK;
  60         struct hid_report_enum *report_enum;
  61         struct hid_report *report;
  62         struct list_head *list;
  63
  64         if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
  65             rinfo->report_type > HID_REPORT_TYPE_MAX)
  66                 return NULL;
  67
  68         report_enum = hid->report_enum +
  69                 (rinfo->report_type - HID_REPORT_TYPE_MIN);
  70
  71         switch (flags) {
  72         case 0: /* Nothing to do -- report_id is already set correctly */
  73                 break;
  74
  75         case HID_REPORT_ID_FIRST:
  76                 if (list_empty(&report_enum->report_list))
  77                         return NULL;
  78
  79                 list = report_enum->report_list.next;
  80                 report = list_entry(list, struct hid_report, list);
  81                 rinfo->report_id = report->id;
  82                 break;
  83
  84         case HID_REPORT_ID_NEXT:
  85                 report = report_enum->report_id_hash[rid];
  86                 if (!report)
  87                         return NULL;
  88
  89                 list = report->list.next;
  90                 if (list == &report_enum->report_list)
  91                         return NULL;
  92
  93                 report = list_entry(list, struct hid_report, list);
  94                 rinfo->report_id = report->id;
  95                 break;
  96
  97         default:
  98                 return NULL;
  99         }
 100
 101         return report_enum->report_id_hash[rinfo->report_id];
 102 }
 103
 104 /*
 105  * Perform an exhaustive search of the report table for a usage, given its
 106  * type and usage id.
 107  */
 108 static struct hid_field *
 109 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
 110 {
 111         int i, j;
 112         struct hid_report *report;
 113         struct hid_report_enum *report_enum;
 114         struct hid_field *field;
 115
 116         if (uref->report_type < HID_REPORT_TYPE_MIN ||
 117             uref->report_type > HID_REPORT_TYPE_MAX)
 118                 return NULL;
 119
 120         report_enum = hid->report_enum +
 121                 (uref->report_type - HID_REPORT_TYPE_MIN);
 122
 123         list_for_each_entry(report, &report_enum->report_list, list) {
 124                 for (i = 0; i < report->maxfield; i++) {
 125                         field = report->field[i];
 126                         for (j = 0; j < field->maxusage; j++) {
 127                                 if (field->usage[j].hid == uref->usage_code) {
 128                                         uref->report_id = report->id;
 129                                         uref->field_index = i;
 130                                         uref->usage_index = j;
 131                                         return field;
 132                                 }
 133                         }
 134                 }
 135         }
 136
 137         return NULL;
 138 }
 139
 140 static void hiddev_send_event(struct hid_device *hid,
 141                               struct hiddev_usage_ref *uref)
 142 {
 143         struct hiddev *hiddev = hid->hiddev;
 144         struct hiddev_list *list;
 145         unsigned long flags;
 146
 147         spin_lock_irqsave(&hiddev->list_lock, flags);
 148         list_for_each_entry(list, &hiddev->list, node) {
 149                 if (uref->field_index != HID_FIELD_INDEX_NONE ||
 150                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 151                         list->buffer[list->head] = *uref;
 152                         list->head = (list->head + 1) &
 153                                 (HIDDEV_BUFFER_SIZE - 1);
 154                         kill_fasync(&list->fasync, SIGIO, POLL_IN);
 155                 }
 156         }
 157         spin_unlock_irqrestore(&hiddev->list_lock, flags);
 158
 159         wake_up_interruptible(&hiddev->wait);
 160 }
 161
 162 /*
 163  * This is where hid.c calls into hiddev to pass an event that occurred over
 164  * the interrupt pipe
 165  */
 166 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
 167                       struct hid_usage *usage, __s32 value)
 168 {
 169         unsigned type = field->report_type;
 170         struct hiddev_usage_ref uref;
 171
 172         uref.report_type =
 173           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
 174           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
 175            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
 176         uref.report_id = field->report->id;
 177         uref.field_index = field->index;
 178         uref.usage_index = (usage - field->usage);
 179         uref.usage_code = usage->hid;
 180         uref.value = value;
 181
 182         hiddev_send_event(hid, &uref);
 183 }
 184 EXPORT_SYMBOL_GPL(hiddev_hid_event);
 185
 186 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
 187 {
 188         unsigned type = report->type;
 189         struct hiddev_usage_ref uref;
 190
 191         memset(&uref, 0, sizeof(uref));
 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 = report->id;
 197         uref.field_index = HID_FIELD_INDEX_NONE;
 198
 199         hiddev_send_event(hid, &uref);
 200 }
 201
 202 /*
 203  * fasync file op
 204  */
 205 static int hiddev_fasync(int fd, struct file *file, int on)
 206 {
 207         struct hiddev_list *list = file->private_data;
 208
 209         return fasync_helper(fd, file, on, &list->fasync);
 210 }
 211
 212
 213 /*
 214  * release file op
 215  */
 216 static int hiddev_release(struct inode * inode, struct file * file)
 217 {
 218         struct hiddev_list *list = file->private_data;
 219         unsigned long flags;
 220
 221         spin_lock_irqsave(&list->hiddev->list_lock, flags);
 222         list_del(&list->node);
 223         spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
 224
 225         mutex_lock(&list->hiddev->existancelock);
 226         if (!--list->hiddev->open) {
 227                 if (list->hiddev->exist) {
 228                         hid_hw_close(list->hiddev->hid);
 229                         hid_hw_power(list->hiddev->hid, PM_HINT_NORMAL);
 230                 } else {
 231                         mutex_unlock(&list->hiddev->existancelock);
 232                         kfree(list->hiddev);
 233                         vfree(list);
 234                         return 0;
 235                 }
 236         }
 237
 238         mutex_unlock(&list->hiddev->existancelock);
 239         vfree(list);
 240
 241         return 0;
 242 }
 243
 244 static int __hiddev_open(struct hiddev *hiddev, struct file *file)
 245 {
 246         struct hiddev_list *list;
 247         int error;
 248
 249         lockdep_assert_held(&hiddev->existancelock);
 250
 251         list = vzalloc(sizeof(*list));
 252         if (!list)
 253                 return -ENOMEM;
 254
 255         mutex_init(&list->thread_lock);
 256         list->hiddev = hiddev;
 257
 258         if (!hiddev->open++) {
 259                 error = hid_hw_power(hiddev->hid, PM_HINT_FULLON);
 260                 if (error < 0)
 261                         goto err_drop_count;
 262
 263                 error = hid_hw_open(hiddev->hid);
 264                 if (error < 0)
 265                         goto err_normal_power;
 266         }
 267
 268         spin_lock_irq(&hiddev->list_lock);
 269         list_add_tail(&list->node, &hiddev->list);
 270         spin_unlock_irq(&hiddev->list_lock);
 271
 272         file->private_data = list;
 273
 274         return 0;
 275
 276 err_normal_power:
 277         hid_hw_power(hiddev->hid, PM_HINT_NORMAL);
 278 err_drop_count:
 279         hiddev->open--;
 280         vfree(list);
 281         return error;
 282 }
 283
 284 /*
 285  * open file op
 286  */
 287 static int hiddev_open(struct inode *inode, struct file *file)
 288 {
 289         struct usb_interface *intf;
 290         struct hid_device *hid;
 291         struct hiddev *hiddev;
 292         int res;
 293
 294         intf = usbhid_find_interface(iminor(inode));
 295         if (!intf)
 296                 return -ENODEV;
 297
 298         hid = usb_get_intfdata(intf);
 299         hiddev = hid->hiddev;
 300
 301         mutex_lock(&hiddev->existancelock);
 302         res = hiddev->exist ? __hiddev_open(hiddev, file) : -ENODEV;
 303         mutex_unlock(&hiddev->existancelock);
 304
 305         return res;
 306 }
 307
 308 /*
 309  * "write" file op
 310  */
 311 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
 312 {
 313         return -EINVAL;
 314 }
 315
 316 /*
 317  * "read" file op
 318  */
 319 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
 320 {
 321         DEFINE_WAIT(wait);
 322         struct hiddev_list *list = file->private_data;
 323         int event_size;
 324         int retval;
 325
 326         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
 327                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
 328
 329         if (count < event_size)
 330                 return 0;
 331
 332         /* lock against other threads */
 333         retval = mutex_lock_interruptible(&list->thread_lock);
 334         if (retval)
 335                 return -ERESTARTSYS;
 336
 337         while (retval == 0) {
 338                 if (list->head == list->tail) {
 339                         prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);
 340
 341                         while (list->head == list->tail) {
 342                                 if (signal_pending(current)) {
 343                                         retval = -ERESTARTSYS;
 344                                         break;
 345                                 }
 346                                 if (!list->hiddev->exist) {
 347                                         retval = -EIO;
 348                                         break;
 349                                 }
 350                                 if (file->f_flags & O_NONBLOCK) {
 351                                         retval = -EAGAIN;
 352                                         break;
 353                                 }
 354
 355                                 /* let O_NONBLOCK tasks run */
 356                                 mutex_unlock(&list->thread_lock);
 357                                 schedule();
 358                                 if (mutex_lock_interruptible(&list->thread_lock)) {
 359                                         finish_wait(&list->hiddev->wait, &wait);
 360                                         return -EINTR;
 361                                 }
 362                                 set_current_state(TASK_INTERRUPTIBLE);
 363                         }
 364                         finish_wait(&list->hiddev->wait, &wait);
 365
 366                 }
 367
 368                 if (retval) {
 369                         mutex_unlock(&list->thread_lock);
 370                         return retval;
 371                 }
 372
 373
 374                 while (list->head != list->tail &&
 375                        retval + event_size <= count) {
 376                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
 377                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
 378                                         struct hiddev_event event;
 379
 380                                         event.hid = list->buffer[list->tail].usage_code;
 381                                         event.value = list->buffer[list->tail].value;
 382                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {
 383                                                 mutex_unlock(&list->thread_lock);
 384                                                 return -EFAULT;
 385                                         }
 386                                         retval += sizeof(struct hiddev_event);
 387                                 }
 388                         } else {
 389                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
 390                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 391
 392                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {
 393                                                 mutex_unlock(&list->thread_lock);
 394                                                 return -EFAULT;
 395                                         }
 396                                         retval += sizeof(struct hiddev_usage_ref);
 397                                 }
 398                         }
 399                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
 400                 }
 401
 402         }
 403         mutex_unlock(&list->thread_lock);
 404
 405         return retval;
 406 }
 407
 408 /*
 409  * "poll" file op
 410  * No kernel lock - fine
 411  */
 412 static __poll_t hiddev_poll(struct file *file, poll_table *wait)
 413 {
 414         struct hiddev_list *list = file->private_data;
 415
 416         poll_wait(file, &list->hiddev->wait, wait);
 417         if (list->head != list->tail)
 418                 return EPOLLIN | EPOLLRDNORM | EPOLLOUT;
 419         if (!list->hiddev->exist)
 420                 return EPOLLERR | EPOLLHUP;
 421         return 0;
 422 }
 423
 424 /*
 425  * "ioctl" file op
 426  */
 427 static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 428 {
 429         struct hid_device *hid = hiddev->hid;
 430         struct hiddev_report_info rinfo;
 431         struct hiddev_usage_ref_multi *uref_multi = NULL;
 432         struct hiddev_usage_ref *uref;
 433         struct hid_report *report;
 434         struct hid_field *field;
 435         int i;
 436
 437         uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
 438         if (!uref_multi)
 439                 return -ENOMEM;
 440         uref = &uref_multi->uref;
 441         if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
 442                 if (copy_from_user(uref_multi, user_arg,
 443                                    sizeof(*uref_multi)))
 444                         goto fault;
 445         } else {
 446                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
 447                         goto fault;
 448         }
 449
 450         switch (cmd) {
 451         case HIDIOCGUCODE:
 452                 rinfo.report_type = uref->report_type;
 453                 rinfo.report_id = uref->report_id;
 454                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 455                         goto inval;
 456
 457                 if (uref->field_index >= report->maxfield)
 458                         goto inval;
 459                 uref->field_index = array_index_nospec(uref->field_index,
 460                                                        report->maxfield);
 461
 462                 field = report->field[uref->field_index];
 463                 if (uref->usage_index >= field->maxusage)
 464                         goto inval;
 465                 uref->usage_index = array_index_nospec(uref->usage_index,
 466                                                        field->maxusage);
 467
 468                 uref->usage_code = field->usage[uref->usage_index].hid;
 469
 470                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
 471                         goto fault;
 472
 473                 goto goodreturn;
 474
 475         default:
 476                 if (cmd != HIDIOCGUSAGE &&
 477                     cmd != HIDIOCGUSAGES &&
 478                     uref->report_type == HID_REPORT_TYPE_INPUT)
 479                         goto inval;
 480
 481                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
 482                         field = hiddev_lookup_usage(hid, uref);
 483                         if (field == NULL)
 484                                 goto inval;
 485                 } else {
 486                         rinfo.report_type = uref->report_type;
 487                         rinfo.report_id = uref->report_id;
 488                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 489                                 goto inval;
 490
 491                         if (uref->field_index >= report->maxfield)
 492                                 goto inval;
 493                         uref->field_index = array_index_nospec(uref->field_index,
 494                                                                report->maxfield);
 495
 496                         field = report->field[uref->field_index];
 497
 498                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
 499                                 if (uref->usage_index >= field->maxusage)
 500                                         goto inval;
 501                                 uref->usage_index =
 502                                         array_index_nospec(uref->usage_index,
 503                                                            field->maxusage);
 504                         } else if (uref->usage_index >= field->report_count)
 505                                 goto inval;
 506                 }
 507
 508                 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
 509                         if (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
 510                             uref->usage_index + uref_multi->num_values >
 511                             field->report_count)
 512                                 goto inval;
 513
 514                         uref->usage_index =
 515                                 array_index_nospec(uref->usage_index,
 516                                                    field->report_count -
 517                                                    uref_multi->num_values);
 518                 }
 519
 520                 switch (cmd) {
 521                 case HIDIOCGUSAGE:
 522                         if (uref->usage_index >= field->report_count)
 523                                 goto inval;
 524                         uref->value = field->value[uref->usage_index];
 525                         if (copy_to_user(user_arg, uref, sizeof(*uref)))
 526                                 goto fault;
 527                         goto goodreturn;
 528
 529                 case HIDIOCSUSAGE:
 530                         if (uref->usage_index >= field->report_count)
 531                                 goto inval;
 532                         field->value[uref->usage_index] = uref->value;
 533                         goto goodreturn;
 534
 535                 case HIDIOCGCOLLECTIONINDEX:
 536                         i = field->usage[uref->usage_index].collection_index;
 537                         kfree(uref_multi);
 538                         return i;
 539                 case HIDIOCGUSAGES:
 540                         for (i = 0; i < uref_multi->num_values; i++)
 541                                 uref_multi->values[i] =
 542                                     field->value[uref->usage_index + i];
 543                         if (copy_to_user(user_arg, uref_multi,
 544                                          sizeof(*uref_multi)))
 545                                 goto fault;
 546                         goto goodreturn;
 547                 case HIDIOCSUSAGES:
 548                         for (i = 0; i < uref_multi->num_values; i++)
 549                                 field->value[uref->usage_index + i] =
 550                                     uref_multi->values[i];
 551                         goto goodreturn;
 552                 }
 553
 554 goodreturn:
 555                 kfree(uref_multi);
 556                 return 0;
 557 fault:
 558                 kfree(uref_multi);
 559                 return -EFAULT;
 560 inval:
 561                 kfree(uref_multi);
 562                 return -EINVAL;
 563         }
 564 }
 565
 566 static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 567 {
 568         struct hid_device *hid = hiddev->hid;
 569         struct usb_device *dev = hid_to_usb_dev(hid);
 570         int idx, len;
 571         char *buf;
 572
 573         if (get_user(idx, (int __user *)user_arg))
 574                 return -EFAULT;
 575
 576         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
 577                 return -ENOMEM;
 578
 579         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
 580                 kfree(buf);
 581                 return -EINVAL;
 582         }
 583
 584         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
 585                 kfree(buf);
 586                 return -EFAULT;
 587         }
 588
 589         kfree(buf);
 590
 591         return len;
 592 }
 593
 594 static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 595 {
 596         struct hiddev_list *list = file->private_data;
 597         struct hiddev *hiddev = list->hiddev;
 598         struct hid_device *hid;
 599         struct hiddev_collection_info cinfo;
 600         struct hiddev_report_info rinfo;
 601         struct hiddev_field_info finfo;
 602         struct hiddev_devinfo dinfo;
 603         struct hid_report *report;
 604         struct hid_field *field;
 605         void __user *user_arg = (void __user *)arg;
 606         int i, r = -EINVAL;
 607
 608         /* Called without BKL by compat methods so no BKL taken */
 609
 610         mutex_lock(&hiddev->existancelock);
 611         if (!hiddev->exist) {
 612                 r = -ENODEV;
 613                 goto ret_unlock;
 614         }
 615
 616         hid = hiddev->hid;
 617
 618         switch (cmd) {
 619
 620         case HIDIOCGVERSION:
 621                 r = put_user(HID_VERSION, (int __user *)arg) ?
 622                         -EFAULT : 0;
 623                 break;
 624
 625         case HIDIOCAPPLICATION:
 626                 if (arg >= hid->maxapplication)
 627                         break;
 628
 629                 for (i = 0; i < hid->maxcollection; i++)
 630                         if (hid->collection[i].type ==
 631                             HID_COLLECTION_APPLICATION && arg-- == 0)
 632                                 break;
 633
 634                 if (i < hid->maxcollection)
 635                         r = hid->collection[i].usage;
 636                 break;
 637
 638         case HIDIOCGDEVINFO:
 639                 {
 640                         struct usb_device *dev = hid_to_usb_dev(hid);
 641                         struct usbhid_device *usbhid = hid->driver_data;
 642
 643                         memset(&dinfo, 0, sizeof(dinfo));
 644
 645                         dinfo.bustype = BUS_USB;
 646                         dinfo.busnum = dev->bus->busnum;
 647                         dinfo.devnum = dev->devnum;
 648                         dinfo.ifnum = usbhid->ifnum;
 649                         dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
 650                         dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
 651                         dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
 652                         dinfo.num_applications = hid->maxapplication;
 653
 654                         r = copy_to_user(user_arg, &dinfo, sizeof(dinfo)) ?
 655                                 -EFAULT : 0;
 656                         break;
 657                 }
 658
 659         case HIDIOCGFLAG:
 660                 r = put_user(list->flags, (int __user *)arg) ?
 661                         -EFAULT : 0;
 662                 break;
 663
 664         case HIDIOCSFLAG:
 665                 {
 666                         int newflags;
 667
 668                         if (get_user(newflags, (int __user *)arg)) {
 669                                 r = -EFAULT;
 670                                 break;
 671                         }
 672
 673                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
 674                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
 675                              (newflags & HIDDEV_FLAG_UREF) == 0))
 676                                 break;
 677
 678                         list->flags = newflags;
 679
 680                         r = 0;
 681                         break;
 682                 }
 683
 684         case HIDIOCGSTRING:
 685                 r = hiddev_ioctl_string(hiddev, cmd, user_arg);
 686                 break;
 687
 688         case HIDIOCINITREPORT:
 689                 usbhid_init_reports(hid);
 690                 hiddev->initialized = true;
 691                 r = 0;
 692                 break;
 693
 694         case HIDIOCGREPORT:
 695                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 696                         r = -EFAULT;
 697                         break;
 698                 }
 699
 700                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
 701                         break;
 702
 703                 report = hiddev_lookup_report(hid, &rinfo);
 704                 if (report == NULL)
 705                         break;
 706
 707                 hid_hw_request(hid, report, HID_REQ_GET_REPORT);
 708                 hid_hw_wait(hid);
 709
 710                 r = 0;
 711                 break;
 712
 713         case HIDIOCSREPORT:
 714                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 715                         r = -EFAULT;
 716                         break;
 717                 }
 718
 719                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
 720                         break;
 721
 722                 report = hiddev_lookup_report(hid, &rinfo);
 723                 if (report == NULL)
 724                         break;
 725
 726                 hid_hw_request(hid, report, HID_REQ_SET_REPORT);
 727                 hid_hw_wait(hid);
 728
 729                 r = 0;
 730                 break;
 731
 732         case HIDIOCGREPORTINFO:
 733                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 734                         r = -EFAULT;
 735                         break;
 736                 }
 737
 738                 report = hiddev_lookup_report(hid, &rinfo);
 739                 if (report == NULL)
 740                         break;
 741
 742                 rinfo.num_fields = report->maxfield;
 743
 744                 r = copy_to_user(user_arg, &rinfo, sizeof(rinfo)) ?
 745                         -EFAULT : 0;
 746                 break;
 747
 748         case HIDIOCGFIELDINFO:
 749                 if (copy_from_user(&finfo, user_arg, sizeof(finfo))) {
 750                         r = -EFAULT;
 751                         break;
 752                 }
 753
 754                 rinfo.report_type = finfo.report_type;
 755                 rinfo.report_id = finfo.report_id;
 756
 757                 report = hiddev_lookup_report(hid, &rinfo);
 758                 if (report == NULL)
 759                         break;
 760
 761                 if (finfo.field_index >= report->maxfield)
 762                         break;
 763                 finfo.field_index = array_index_nospec(finfo.field_index,
 764                                                        report->maxfield);
 765
 766                 field = report->field[finfo.field_index];
 767                 memset(&finfo, 0, sizeof(finfo));
 768                 finfo.report_type = rinfo.report_type;
 769                 finfo.report_id = rinfo.report_id;
 770                 finfo.field_index = field->report_count - 1;
 771                 finfo.maxusage = field->maxusage;
 772                 finfo.flags = field->flags;
 773                 finfo.physical = field->physical;
 774                 finfo.logical = field->logical;
 775                 finfo.application = field->application;
 776                 finfo.logical_minimum = field->logical_minimum;
 777                 finfo.logical_maximum = field->logical_maximum;
 778                 finfo.physical_minimum = field->physical_minimum;
 779                 finfo.physical_maximum = field->physical_maximum;
 780                 finfo.unit_exponent = field->unit_exponent;
 781                 finfo.unit = field->unit;
 782
 783                 r = copy_to_user(user_arg, &finfo, sizeof(finfo)) ?
 784                         -EFAULT : 0;
 785                 break;
 786
 787         case HIDIOCGUCODE:
 788         case HIDIOCGUSAGE:
 789         case HIDIOCSUSAGE:
 790         case HIDIOCGUSAGES:
 791         case HIDIOCSUSAGES:
 792         case HIDIOCGCOLLECTIONINDEX:
 793                 if (!hiddev->initialized) {
 794                         usbhid_init_reports(hid);
 795                         hiddev->initialized = true;
 796                 }
 797                 r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
 798                 break;
 799
 800         case HIDIOCGCOLLECTIONINFO:
 801                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo))) {
 802                         r = -EFAULT;
 803                         break;
 804                 }
 805
 806                 if (cinfo.index >= hid->maxcollection)
 807                         break;
 808                 cinfo.index = array_index_nospec(cinfo.index,
 809                                                  hid->maxcollection);
 810
 811                 cinfo.type = hid->collection[cinfo.index].type;
 812                 cinfo.usage = hid->collection[cinfo.index].usage;
 813                 cinfo.level = hid->collection[cinfo.index].level;
 814
 815                 r = copy_to_user(user_arg, &cinfo, sizeof(cinfo)) ?
 816                         -EFAULT : 0;
 817                 break;
 818
 819         default:
 820                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
 821                         break;
 822
 823                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
 824                         int len = strlen(hid->name) + 1;
 825                         if (len > _IOC_SIZE(cmd))
 826                                  len = _IOC_SIZE(cmd);
 827                         r = copy_to_user(user_arg, hid->name, len) ?
 828                                 -EFAULT : len;
 829                         break;
 830                 }
 831
 832                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
 833                         int len = strlen(hid->phys) + 1;
 834                         if (len > _IOC_SIZE(cmd))
 835                                 len = _IOC_SIZE(cmd);
 836                         r = copy_to_user(user_arg, hid->phys, len) ?
 837                                 -EFAULT : len;
 838                         break;
 839                 }
 840         }
 841
 842 ret_unlock:
 843         mutex_unlock(&hiddev->existancelock);
 844         return r;
 845 }
 846
 847 static const struct file_operations hiddev_fops = {
 848         .owner =        THIS_MODULE,
 849         .read =         hiddev_read,
 850         .write =        hiddev_write,
 851         .poll =         hiddev_poll,
 852         .open =         hiddev_open,
 853         .release =      hiddev_release,
 854         .unlocked_ioctl =       hiddev_ioctl,
 855         .fasync =       hiddev_fasync,
 856         .compat_ioctl   = compat_ptr_ioctl,
 857         .llseek         = noop_llseek,
 858 };
 859
 860 static char *hiddev_devnode(struct device *dev, umode_t *mode)
 861 {
 862         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
 863 }
 864
 865 static struct usb_class_driver hiddev_class = {
 866         .name =         "hiddev%d",
 867         .devnode =      hiddev_devnode,
 868         .fops =         &hiddev_fops,
 869         .minor_base =   HIDDEV_MINOR_BASE,
 870 };
 871
 872 /*
 873  * This is where hid.c calls us to connect a hid device to the hiddev driver
 874  */
 875 int hiddev_connect(struct hid_device *hid, unsigned int force)
 876 {
 877         struct hiddev *hiddev;
 878         struct usbhid_device *usbhid = hid->driver_data;
 879         int retval;
 880
 881         if (!force) {
 882                 unsigned int i;
 883                 for (i = 0; i < hid->maxcollection; i++)
 884                         if (hid->collection[i].type ==
 885                             HID_COLLECTION_APPLICATION &&
 886                             !IS_INPUT_APPLICATION(hid->collection[i].usage))
 887                                 break;
 888
 889                 if (i == hid->maxcollection)
 890                         return -1;
 891         }
 892
 893         if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
 894                 return -1;
 895
 896         init_waitqueue_head(&hiddev->wait);
 897         INIT_LIST_HEAD(&hiddev->list);
 898         spin_lock_init(&hiddev->list_lock);
 899         mutex_init(&hiddev->existancelock);
 900         hid->hiddev = hiddev;
 901         hiddev->hid = hid;
 902         hiddev->exist = 1;
 903         retval = usb_register_dev(usbhid->intf, &hiddev_class);
 904         if (retval) {
 905                 hid_err(hid, "Not able to get a minor for this device\n");
 906                 hid->hiddev = NULL;
 907                 kfree(hiddev);
 908                 return -1;
 909         }
 910
 911         /*
 912          * If HID_QUIRK_NO_INIT_REPORTS is set, make sure we don't initialize
 913          * the reports.
 914          */
 915         hiddev->initialized = hid->quirks & HID_QUIRK_NO_INIT_REPORTS;
 916
 917         hiddev->minor = usbhid->intf->minor;
 918
 919         return 0;
 920 }
 921
 922 /*
 923  * This is where hid.c calls us to disconnect a hiddev device from the
 924  * corresponding hid device (usually because the usb device has disconnected)
 925  */
 926 static struct usb_class_driver hiddev_class;
 927 void hiddev_disconnect(struct hid_device *hid)
 928 {
 929         struct hiddev *hiddev = hid->hiddev;
 930         struct usbhid_device *usbhid = hid->driver_data;
 931
 932         usb_deregister_dev(usbhid->intf, &hiddev_class);
 933
 934         mutex_lock(&hiddev->existancelock);
 935         hiddev->exist = 0;
 936
 937         if (hiddev->open) {
 938                 hid_hw_close(hiddev->hid);
 939                 wake_up_interruptible(&hiddev->wait);
 940                 mutex_unlock(&hiddev->existancelock);
 941         } else {
 942                 mutex_unlock(&hiddev->existancelock);
 943                 kfree(hiddev);
 944         }
 945 }