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         mutex_lock(&list->hiddev->existancelock);
 246         if (!--list->hiddev->open) {
 247                 if (list->hiddev->exist) {
 248                         usbhid_close(list->hiddev->hid);
 249                         usbhid_put_power(list->hiddev->hid);
 250                 } else {
 251                         mutex_unlock(&list->hiddev->existancelock);
 252                         kfree(list->hiddev);
 253                         kfree(list);
 254                         return 0;
 255                 }
 256         }
 257
 258         mutex_unlock(&list->hiddev->existancelock);
 259         kfree(list);
 260
 261         return 0;
 262 }
 263
 264 /*
 265  * open file op
 266  */
 267 static int hiddev_open(struct inode *inode, struct file *file)
 268 {
 269         struct hiddev_list *list;
 270         struct usb_interface *intf;
 271         struct hid_device *hid;
 272         struct hiddev *hiddev;
 273         int res;
 274
 275         intf = usbhid_find_interface(iminor(inode));
 276         if (!intf)
 277                 return -ENODEV;
 278         hid = usb_get_intfdata(intf);
 279         hiddev = hid->hiddev;
 280
 281         if (!(list = kzalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
 282                 return -ENOMEM;
 283         mutex_init(&list->thread_lock);
 284         list->hiddev = hiddev;
 285         file->private_data = list;
 286
 287         /*
 288          * no need for locking because the USB major number
 289          * is shared which usbcore guards against disconnect
 290          */
 291         if (list->hiddev->exist) {
 292                 if (!list->hiddev->open++) {
 293                         res = usbhid_open(hiddev->hid);
 294                         if (res < 0) {
 295                                 res = -EIO;
 296                                 goto bail;
 297                         }
 298                 }
 299         } else {
 300                 res = -ENODEV;
 301                 goto bail;
 302         }
 303
 304         spin_lock_irq(&list->hiddev->list_lock);
 305         list_add_tail(&list->node, &hiddev->list);
 306         spin_unlock_irq(&list->hiddev->list_lock);
 307
 308         mutex_lock(&hiddev->existancelock);
 309         if (!list->hiddev->open++)
 310                 if (list->hiddev->exist) {
 311                         struct hid_device *hid = hiddev->hid;
 312                         res = usbhid_get_power(hid);
 313                         if (res < 0) {
 314                                 res = -EIO;
 315                                 goto bail_unlock;
 316                         }
 317                         usbhid_open(hid);
 318                 }
 319         mutex_unlock(&hiddev->existancelock);
 320         return 0;
 321 bail_unlock:
 322         mutex_unlock(&hiddev->existancelock);
 323 bail:
 324         file->private_data = NULL;
 325         kfree(list);
 326         return res;
 327 }
 328
 329 /*
 330  * "write" file op
 331  */
 332 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
 333 {
 334         return -EINVAL;
 335 }
 336
 337 /*
 338  * "read" file op
 339  */
 340 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
 341 {
 342         DEFINE_WAIT(wait);
 343         struct hiddev_list *list = file->private_data;
 344         int event_size;
 345         int retval;
 346
 347         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
 348                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
 349
 350         if (count < event_size)
 351                 return 0;
 352
 353         /* lock against other threads */
 354         retval = mutex_lock_interruptible(&list->thread_lock);
 355         if (retval)
 356                 return -ERESTARTSYS;
 357
 358         while (retval == 0) {
 359                 if (list->head == list->tail) {
 360                         prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);
 361
 362                         while (list->head == list->tail) {
 363                                 if (file->f_flags & O_NONBLOCK) {
 364                                         retval = -EAGAIN;
 365                                         break;
 366                                 }
 367                                 if (signal_pending(current)) {
 368                                         retval = -ERESTARTSYS;
 369                                         break;
 370                                 }
 371                                 if (!list->hiddev->exist) {
 372                                         retval = -EIO;
 373                                         break;
 374                                 }
 375
 376                                 /* let O_NONBLOCK tasks run */
 377                                 mutex_unlock(&list->thread_lock);
 378                                 schedule();
 379                                 if (mutex_lock_interruptible(&list->thread_lock)) {
 380                                         finish_wait(&list->hiddev->wait, &wait);
 381                                         return -EINTR;
 382                                 }
 383                                 set_current_state(TASK_INTERRUPTIBLE);
 384                         }
 385                         finish_wait(&list->hiddev->wait, &wait);
 386
 387                 }
 388
 389                 if (retval) {
 390                         mutex_unlock(&list->thread_lock);
 391                         return retval;
 392                 }
 393
 394
 395                 while (list->head != list->tail &&
 396                        retval + event_size <= count) {
 397                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
 398                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
 399                                         struct hiddev_event event;
 400
 401                                         event.hid = list->buffer[list->tail].usage_code;
 402                                         event.value = list->buffer[list->tail].value;
 403                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {
 404                                                 mutex_unlock(&list->thread_lock);
 405                                                 return -EFAULT;
 406                                         }
 407                                         retval += sizeof(struct hiddev_event);
 408                                 }
 409                         } else {
 410                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
 411                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 412
 413                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {
 414                                                 mutex_unlock(&list->thread_lock);
 415                                                 return -EFAULT;
 416                                         }
 417                                         retval += sizeof(struct hiddev_usage_ref);
 418                                 }
 419                         }
 420                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
 421                 }
 422
 423         }
 424         mutex_unlock(&list->thread_lock);
 425
 426         return retval;
 427 }
 428
 429 /*
 430  * "poll" file op
 431  * No kernel lock - fine
 432  */
 433 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
 434 {
 435         struct hiddev_list *list = file->private_data;
 436
 437         poll_wait(file, &list->hiddev->wait, wait);
 438         if (list->head != list->tail)
 439                 return POLLIN | POLLRDNORM;
 440         if (!list->hiddev->exist)
 441                 return POLLERR | POLLHUP;
 442         return 0;
 443 }
 444
 445 /*
 446  * "ioctl" file op
 447  */
 448 static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 449 {
 450         struct hid_device *hid = hiddev->hid;
 451         struct hiddev_report_info rinfo;
 452         struct hiddev_usage_ref_multi *uref_multi = NULL;
 453         struct hiddev_usage_ref *uref;
 454         struct hid_report *report;
 455         struct hid_field *field;
 456         int i;
 457
 458         uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
 459         if (!uref_multi)
 460                 return -ENOMEM;
 461         uref = &uref_multi->uref;
 462         if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
 463                 if (copy_from_user(uref_multi, user_arg,
 464                                    sizeof(*uref_multi)))
 465                         goto fault;
 466         } else {
 467                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
 468                         goto fault;
 469         }
 470
 471         switch (cmd) {
 472         case HIDIOCGUCODE:
 473                 rinfo.report_type = uref->report_type;
 474                 rinfo.report_id = uref->report_id;
 475                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 476                         goto inval;
 477
 478                 if (uref->field_index >= report->maxfield)
 479                         goto inval;
 480
 481                 field = report->field[uref->field_index];
 482                 if (uref->usage_index >= field->maxusage)
 483                         goto inval;
 484
 485                 uref->usage_code = field->usage[uref->usage_index].hid;
 486
 487                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
 488                         goto fault;
 489
 490                 goto goodreturn;
 491
 492         default:
 493                 if (cmd != HIDIOCGUSAGE &&
 494                     cmd != HIDIOCGUSAGES &&
 495                     uref->report_type == HID_REPORT_TYPE_INPUT)
 496                         goto inval;
 497
 498                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
 499                         field = hiddev_lookup_usage(hid, uref);
 500                         if (field == NULL)
 501                                 goto inval;
 502                 } else {
 503                         rinfo.report_type = uref->report_type;
 504                         rinfo.report_id = uref->report_id;
 505                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 506                                 goto inval;
 507
 508                         if (uref->field_index >= report->maxfield)
 509                                 goto inval;
 510
 511                         field = report->field[uref->field_index];
 512
 513                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
 514                                 if (uref->usage_index >= field->maxusage)
 515                                         goto inval;
 516                         } else if (uref->usage_index >= field->report_count)
 517                                 goto inval;
 518
 519                         else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
 520                                  (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
 521                                   uref->usage_index + uref_multi->num_values > field->report_count))
 522                                 goto inval;
 523                 }
 524
 525                 switch (cmd) {
 526                 case HIDIOCGUSAGE:
 527                         uref->value = field->value[uref->usage_index];
 528                         if (copy_to_user(user_arg, uref, sizeof(*uref)))
 529                                 goto fault;
 530                         goto goodreturn;
 531
 532                 case HIDIOCSUSAGE:
 533                         field->value[uref->usage_index] = uref->value;
 534                         goto goodreturn;
 535
 536                 case HIDIOCGCOLLECTIONINDEX:
 537                         i = field->usage[uref->usage_index].collection_index;
 538                         kfree(uref_multi);
 539                         return i;
 540                 case HIDIOCGUSAGES:
 541                         for (i = 0; i < uref_multi->num_values; i++)
 542                                 uref_multi->values[i] =
 543                                     field->value[uref->usage_index + i];
 544                         if (copy_to_user(user_arg, uref_multi,
 545                                          sizeof(*uref_multi)))
 546                                 goto fault;
 547                         goto goodreturn;
 548                 case HIDIOCSUSAGES:
 549                         for (i = 0; i < uref_multi->num_values; i++)
 550                                 field->value[uref->usage_index + i] =
 551                                     uref_multi->values[i];
 552                         goto goodreturn;
 553                 }
 554
 555 goodreturn:
 556                 kfree(uref_multi);
 557                 return 0;
 558 fault:
 559                 kfree(uref_multi);
 560                 return -EFAULT;
 561 inval:
 562                 kfree(uref_multi);
 563                 return -EINVAL;
 564         }
 565 }
 566
 567 static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 568 {
 569         struct hid_device *hid = hiddev->hid;
 570         struct usb_device *dev = hid_to_usb_dev(hid);
 571         int idx, len;
 572         char *buf;
 573
 574         if (get_user(idx, (int __user *)user_arg))
 575                 return -EFAULT;
 576
 577         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
 578                 return -ENOMEM;
 579
 580         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
 581                 kfree(buf);
 582                 return -EINVAL;
 583         }
 584
 585         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
 586                 kfree(buf);
 587                 return -EFAULT;
 588         }
 589
 590         kfree(buf);
 591
 592         return len;
 593 }
 594
 595 static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 596 {
 597         struct hiddev_list *list = file->private_data;
 598         struct hiddev *hiddev = list->hiddev;
 599         struct hid_device *hid;
 600         struct hiddev_collection_info cinfo;
 601         struct hiddev_report_info rinfo;
 602         struct hiddev_field_info finfo;
 603         struct hiddev_devinfo dinfo;
 604         struct hid_report *report;
 605         struct hid_field *field;
 606         void __user *user_arg = (void __user *)arg;
 607         int i, r = -EINVAL;
 608
 609         /* Called without BKL by compat methods so no BKL taken */
 610
 611         mutex_lock(&hiddev->existancelock);
 612         if (!hiddev->exist) {
 613                 r = -ENODEV;
 614                 goto ret_unlock;
 615         }
 616
 617         hid = hiddev->hid;
 618
 619         switch (cmd) {
 620
 621         case HIDIOCGVERSION:
 622                 r = put_user(HID_VERSION, (int __user *)arg) ?
 623                         -EFAULT : 0;
 624                 break;
 625
 626         case HIDIOCAPPLICATION:
 627                 if (arg < 0 || arg >= hid->maxapplication)
 628                         break;
 629
 630                 for (i = 0; i < hid->maxcollection; i++)
 631                         if (hid->collection[i].type ==
 632                             HID_COLLECTION_APPLICATION && arg-- == 0)
 633                                 break;
 634
 635                 if (i < hid->maxcollection)
 636                         r = hid->collection[i].usage;
 637                 break;
 638
 639         case HIDIOCGDEVINFO:
 640                 {
 641                         struct usb_device *dev = hid_to_usb_dev(hid);
 642                         struct usbhid_device *usbhid = hid->driver_data;
 643
 644                         dinfo.bustype = BUS_USB;
 645                         dinfo.busnum = dev->bus->busnum;
 646                         dinfo.devnum = dev->devnum;
 647                         dinfo.ifnum = usbhid->ifnum;
 648                         dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
 649                         dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
 650                         dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
 651                         dinfo.num_applications = hid->maxapplication;
 652
 653                         r = copy_to_user(user_arg, &dinfo, sizeof(dinfo)) ?
 654                                 -EFAULT : 0;
 655                         break;
 656                 }
 657
 658         case HIDIOCGFLAG:
 659                 r = put_user(list->flags, (int __user *)arg) ?
 660                         -EFAULT : 0;
 661                 break;
 662
 663         case HIDIOCSFLAG:
 664                 {
 665                         int newflags;
 666
 667                         if (get_user(newflags, (int __user *)arg)) {
 668                                 r = -EFAULT;
 669                                 break;
 670                         }
 671
 672                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
 673                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
 674                              (newflags & HIDDEV_FLAG_UREF) == 0))
 675                                 break;
 676
 677                         list->flags = newflags;
 678
 679                         r = 0;
 680                         break;
 681                 }
 682
 683         case HIDIOCGSTRING:
 684                 r = hiddev_ioctl_string(hiddev, cmd, user_arg);
 685                 break;
 686
 687         case HIDIOCINITREPORT:
 688                 usbhid_init_reports(hid);
 689                 r = 0;
 690                 break;
 691
 692         case HIDIOCGREPORT:
 693                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 694                         r = -EFAULT;
 695                         break;
 696                 }
 697
 698                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
 699                         break;
 700
 701                 report = hiddev_lookup_report(hid, &rinfo);
 702                 if (report == NULL)
 703                         break;
 704
 705                 usbhid_submit_report(hid, report, USB_DIR_IN);
 706                 usbhid_wait_io(hid);
 707
 708                 r = 0;
 709                 break;
 710
 711         case HIDIOCSREPORT:
 712                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 713                         r = -EFAULT;
 714                         break;
 715                 }
 716
 717                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
 718                         break;
 719
 720                 report = hiddev_lookup_report(hid, &rinfo);
 721                 if (report == NULL)
 722                         break;
 723
 724                 usbhid_submit_report(hid, report, USB_DIR_OUT);
 725                 usbhid_wait_io(hid);
 726
 727                 r = 0;
 728                 break;
 729
 730         case HIDIOCGREPORTINFO:
 731                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 732                         r = -EFAULT;
 733                         break;
 734                 }
 735
 736                 report = hiddev_lookup_report(hid, &rinfo);
 737                 if (report == NULL)
 738                         break;
 739
 740                 rinfo.num_fields = report->maxfield;
 741
 742                 r = copy_to_user(user_arg, &rinfo, sizeof(rinfo)) ?
 743                         -EFAULT : 0;
 744                 break;
 745
 746         case HIDIOCGFIELDINFO:
 747                 if (copy_from_user(&finfo, user_arg, sizeof(finfo))) {
 748                         r = -EFAULT;
 749                         break;
 750                 }
 751
 752                 rinfo.report_type = finfo.report_type;
 753                 rinfo.report_id = finfo.report_id;
 754
 755                 report = hiddev_lookup_report(hid, &rinfo);
 756                 if (report == NULL)
 757                         break;
 758
 759                 if (finfo.field_index >= report->maxfield)
 760                         break;
 761
 762                 field = report->field[finfo.field_index];
 763                 memset(&finfo, 0, sizeof(finfo));
 764                 finfo.report_type = rinfo.report_type;
 765                 finfo.report_id = rinfo.report_id;
 766                 finfo.field_index = field->report_count - 1;
 767                 finfo.maxusage = field->maxusage;
 768                 finfo.flags = field->flags;
 769                 finfo.physical = field->physical;
 770                 finfo.logical = field->logical;
 771                 finfo.application = field->application;
 772                 finfo.logical_minimum = field->logical_minimum;
 773                 finfo.logical_maximum = field->logical_maximum;
 774                 finfo.physical_minimum = field->physical_minimum;
 775                 finfo.physical_maximum = field->physical_maximum;
 776                 finfo.unit_exponent = field->unit_exponent;
 777                 finfo.unit = field->unit;
 778
 779                 r = copy_to_user(user_arg, &finfo, sizeof(finfo)) ?
 780                         -EFAULT : 0;
 781                 break;
 782
 783         case HIDIOCGUCODE:
 784                 /* fall through */
 785         case HIDIOCGUSAGE:
 786         case HIDIOCSUSAGE:
 787         case HIDIOCGUSAGES:
 788         case HIDIOCSUSAGES:
 789         case HIDIOCGCOLLECTIONINDEX:
 790                 r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
 791                 break;
 792
 793         case HIDIOCGCOLLECTIONINFO:
 794                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo))) {
 795                         r = -EFAULT;
 796                         break;
 797                 }
 798
 799                 if (cinfo.index >= hid->maxcollection)
 800                         break;
 801
 802                 cinfo.type = hid->collection[cinfo.index].type;
 803                 cinfo.usage = hid->collection[cinfo.index].usage;
 804                 cinfo.level = hid->collection[cinfo.index].level;
 805
 806                 r = copy_to_user(user_arg, &cinfo, sizeof(cinfo)) ?
 807                         -EFAULT : 0;
 808                 break;
 809
 810         default:
 811                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
 812                         break;
 813
 814                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
 815                         int len = strlen(hid->name) + 1;
 816                         if (len > _IOC_SIZE(cmd))
 817                                  len = _IOC_SIZE(cmd);
 818                         r = copy_to_user(user_arg, hid->name, len) ?
 819                                 -EFAULT : len;
 820                         break;
 821                 }
 822
 823                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
 824                         int len = strlen(hid->phys) + 1;
 825                         if (len > _IOC_SIZE(cmd))
 826                                 len = _IOC_SIZE(cmd);
 827                         r = copy_to_user(user_arg, hid->phys, len) ?
 828                                 -EFAULT : len;
 829                         break;
 830                 }
 831         }
 832
 833 ret_unlock:
 834         mutex_unlock(&hiddev->existancelock);
 835         return r;
 836 }
 837
 838 #ifdef CONFIG_COMPAT
 839 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 840 {
 841         return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
 842 }
 843 #endif
 844
 845 static const struct file_operations hiddev_fops = {
 846         .owner =        THIS_MODULE,
 847         .read =         hiddev_read,
 848         .write =        hiddev_write,
 849         .poll =         hiddev_poll,
 850         .open =         hiddev_open,
 851         .release =      hiddev_release,
 852         .unlocked_ioctl =       hiddev_ioctl,
 853         .fasync =       hiddev_fasync,
 854 #ifdef CONFIG_COMPAT
 855         .compat_ioctl   = hiddev_compat_ioctl,
 856 #endif
 857         .llseek         = noop_llseek,
 858 };
 859
 860 static char *hiddev_devnode(struct device *dev, mode_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         return 0;
 911 }
 912
 913 /*
 914  * This is where hid.c calls us to disconnect a hiddev device from the
 915  * corresponding hid device (usually because the usb device has disconnected)
 916  */
 917 static struct usb_class_driver hiddev_class;
 918 void hiddev_disconnect(struct hid_device *hid)
 919 {
 920         struct hiddev *hiddev = hid->hiddev;
 921         struct usbhid_device *usbhid = hid->driver_data;
 922
 923         mutex_lock(&hiddev->existancelock);
 924         hiddev->exist = 0;
 925
 926         usb_deregister_dev(usbhid->intf, &hiddev_class);
 927
 928         if (hiddev->open) {
 929                 mutex_unlock(&hiddev->existancelock);
 930                 usbhid_close(hiddev->hid);
 931                 wake_up_interruptible(&hiddev->wait);
 932         } else {
 933                 mutex_unlock(&hiddev->existancelock);
 934                 kfree(hiddev);
 935         }
 936 }