drivers/usb/input/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/config.h>
  29 #include <linux/poll.h>
  30 #include <linux/slab.h>
  31 #include <linux/module.h>
  32 #include <linux/init.h>
  33 #include <linux/smp_lock.h>
  34 #include <linux/input.h>
  35 #include <linux/usb.h>
  36 #include "hid.h"
  37 #include <linux/hiddev.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      64
  47
  48 struct hiddev {
  49         int exist;
  50         int open;
  51         wait_queue_head_t wait;
  52         struct hid_device *hid;
  53         struct hiddev_list *list;
  54 };
  55
  56 struct hiddev_list {
  57         struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
  58         int head;
  59         int tail;
  60         unsigned flags;
  61         struct fasync_struct *fasync;
  62         struct hiddev *hiddev;
  63         struct hiddev_list *next;
  64 };
  65
  66 static struct hiddev *hiddev_table[HIDDEV_MINORS];
  67
  68 /*
  69  * Find a report, given the report's type and ID.  The ID can be specified
  70  * indirectly by REPORT_ID_FIRST (which returns the first report of the given
  71  * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
  72  * given type which follows old_id.
  73  */
  74 static struct hid_report *
  75 hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
  76 {
  77         unsigned flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
  78         struct hid_report_enum *report_enum;
  79         struct list_head *list;
  80
  81         if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
  82             rinfo->report_type > HID_REPORT_TYPE_MAX) return NULL;
  83
  84         report_enum = hid->report_enum +
  85                 (rinfo->report_type - HID_REPORT_TYPE_MIN);
  86
  87         switch (flags) {
  88         case 0: /* Nothing to do -- report_id is already set correctly */
  89                 break;
  90
  91         case HID_REPORT_ID_FIRST:
  92                 list = report_enum->report_list.next;
  93                 if (list == &report_enum->report_list)
  94                         return NULL;
  95                 rinfo->report_id = ((struct hid_report *) list)->id;
  96                 break;
  97
  98         case HID_REPORT_ID_NEXT:
  99                 list = (struct list_head *)
 100                         report_enum->report_id_hash[rinfo->report_id & HID_REPORT_ID_MASK];
 101                 if (list == NULL)
 102                         return NULL;
 103                 list = list->next;
 104                 if (list == &report_enum->report_list)
 105                         return NULL;
 106                 rinfo->report_id = ((struct hid_report *) list)->id;
 107                 break;
 108
 109         default:
 110                 return NULL;
 111         }
 112
 113         return report_enum->report_id_hash[rinfo->report_id];
 114 }
 115
 116 /*
 117  * Perform an exhaustive search of the report table for a usage, given its
 118  * type and usage id.
 119  */
 120 static struct hid_field *
 121 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
 122 {
 123         int i, j;
 124         struct hid_report *report;
 125         struct hid_report_enum *report_enum;
 126         struct hid_field *field;
 127
 128         if (uref->report_type < HID_REPORT_TYPE_MIN ||
 129             uref->report_type > HID_REPORT_TYPE_MAX) return NULL;
 130
 131         report_enum = hid->report_enum +
 132                 (uref->report_type - HID_REPORT_TYPE_MIN);
 133
 134         list_for_each_entry(report, &report_enum->report_list, list)
 135                 for (i = 0; i < report->maxfield; i++) {
 136                         field = report->field[i];
 137                         for (j = 0; j < field->maxusage; j++) {
 138                                 if (field->usage[j].hid == uref->usage_code) {
 139                                         uref->report_id = report->id;
 140                                         uref->field_index = i;
 141                                         uref->usage_index = j;
 142                                         return field;
 143                                 }
 144                         }
 145                 }
 146
 147         return NULL;
 148 }
 149
 150 static void hiddev_send_event(struct hid_device *hid,
 151                               struct hiddev_usage_ref *uref)
 152 {
 153         struct hiddev *hiddev = hid->hiddev;
 154         struct hiddev_list *list = hiddev->list;
 155
 156         while (list) {
 157                 if (uref->field_index != HID_FIELD_INDEX_NONE ||
 158                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 159                         list->buffer[list->head] = *uref;
 160                         list->head = (list->head + 1) &
 161                                 (HIDDEV_BUFFER_SIZE - 1);
 162                         kill_fasync(&list->fasync, SIGIO, POLL_IN);
 163                 }
 164
 165                 list = list->next;
 166         }
 167
 168         wake_up_interruptible(&hiddev->wait);
 169 }
 170
 171 /*
 172  * This is where hid.c calls into hiddev to pass an event that occurred over
 173  * the interrupt pipe
 174  */
 175 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
 176                       struct hid_usage *usage, __s32 value, struct pt_regs *regs)
 177 {
 178         unsigned type = field->report_type;
 179         struct hiddev_usage_ref uref;
 180
 181         uref.report_type =
 182           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
 183           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
 184            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE:0));
 185         uref.report_id = field->report->id;
 186         uref.field_index = field->index;
 187         uref.usage_index = (usage - field->usage);
 188         uref.usage_code = usage->hid;
 189         uref.value = value;
 190
 191         hiddev_send_event(hid, &uref);
 192 }
 193
 194
 195 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
 196 {
 197         unsigned type = report->type;
 198         struct hiddev_usage_ref uref;
 199
 200         memset(&uref, 0, sizeof(uref));
 201         uref.report_type =
 202           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
 203           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
 204            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE:0));
 205         uref.report_id = report->id;
 206         uref.field_index = HID_FIELD_INDEX_NONE;
 207
 208         hiddev_send_event(hid, &uref);
 209 }
 210 /*
 211  * fasync file op
 212  */
 213 static int hiddev_fasync(int fd, struct file *file, int on)
 214 {
 215         int retval;
 216         struct hiddev_list *list = file->private_data;
 217         retval = fasync_helper(fd, file, on, &list->fasync);
 218         return retval < 0 ? retval : 0;
 219 }
 220
 221
 222 /*
 223  * release file op
 224  */
 225 static int hiddev_release(struct inode * inode, struct file * file)
 226 {
 227         struct hiddev_list *list = file->private_data;
 228         struct hiddev_list **listptr;
 229
 230         listptr = &list->hiddev->list;
 231         hiddev_fasync(-1, file, 0);
 232
 233         while (*listptr && (*listptr != list))
 234                 listptr = &((*listptr)->next);
 235         *listptr = (*listptr)->next;
 236
 237         if (!--list->hiddev->open) {
 238                 if (list->hiddev->exist)
 239                         hid_close(list->hiddev->hid);
 240                 else
 241                         kfree(list->hiddev);
 242         }
 243
 244         kfree(list);
 245
 246         return 0;
 247 }
 248
 249 /*
 250  * open file op
 251  */
 252 static int hiddev_open(struct inode * inode, struct file * file) {
 253         struct hiddev_list *list;
 254
 255         int i = iminor(inode) - HIDDEV_MINOR_BASE;
 256
 257         if (i >= HIDDEV_MINORS || !hiddev_table[i])
 258                 return -ENODEV;
 259
 260         if (!(list = kmalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
 261                 return -ENOMEM;
 262         memset(list, 0, sizeof(struct hiddev_list));
 263
 264         list->hiddev = hiddev_table[i];
 265         list->next = hiddev_table[i]->list;
 266         hiddev_table[i]->list = list;
 267
 268         file->private_data = list;
 269
 270         if (!list->hiddev->open++)
 271                 if (list->hiddev->exist)
 272                         hid_open(hiddev_table[i]->hid);
 273
 274         return 0;
 275 }
 276
 277 /*
 278  * "write" file op
 279  */
 280 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
 281 {
 282         return -EINVAL;
 283 }
 284
 285 /*
 286  * "read" file op
 287  */
 288 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
 289 {
 290         DECLARE_WAITQUEUE(wait, current);
 291         struct hiddev_list *list = file->private_data;
 292         int event_size;
 293         int retval = 0;
 294
 295         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
 296                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
 297
 298         if (count < event_size)
 299                 return 0;
 300
 301         while (retval == 0) {
 302                 if (list->head == list->tail) {
 303                         add_wait_queue(&list->hiddev->wait, &wait);
 304                         set_current_state(TASK_INTERRUPTIBLE);
 305
 306                         while (list->head == list->tail) {
 307                                 if (file->f_flags & O_NONBLOCK) {
 308                                         retval = -EAGAIN;
 309                                         break;
 310                                 }
 311                                 if (signal_pending(current)) {
 312                                         retval = -ERESTARTSYS;
 313                                         break;
 314                                 }
 315                                 if (!list->hiddev->exist) {
 316                                         retval = -EIO;
 317                                         break;
 318                                 }
 319
 320                                 schedule();
 321                         }
 322
 323                         set_current_state(TASK_RUNNING);
 324                         remove_wait_queue(&list->hiddev->wait, &wait);
 325                 }
 326
 327                 if (retval)
 328                         return retval;
 329
 330
 331                 while (list->head != list->tail &&
 332                        retval + event_size <= count) {
 333                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
 334                                 if (list->buffer[list->tail].field_index !=
 335                                     HID_FIELD_INDEX_NONE) {
 336                                         struct hiddev_event event;
 337                                         event.hid = list->buffer[list->tail].usage_code;
 338                                         event.value = list->buffer[list->tail].value;
 339                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event)))
 340                                                 return -EFAULT;
 341                                         retval += sizeof(struct hiddev_event);
 342                                 }
 343                         } else {
 344                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
 345                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 346                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref)))
 347                                                 return -EFAULT;
 348                                         retval += sizeof(struct hiddev_usage_ref);
 349                                 }
 350                         }
 351                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
 352                 }
 353
 354         }
 355
 356         return retval;
 357 }
 358
 359 /*
 360  * "poll" file op
 361  * No kernel lock - fine
 362  */
 363 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
 364 {
 365         struct hiddev_list *list = file->private_data;
 366         poll_wait(file, &list->hiddev->wait, wait);
 367         if (list->head != list->tail)
 368                 return POLLIN | POLLRDNORM;
 369         if (!list->hiddev->exist)
 370                 return POLLERR | POLLHUP;
 371         return 0;
 372 }
 373
 374 /*
 375  * "ioctl" file op
 376  */
 377 static int hiddev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 378 {
 379         struct hiddev_list *list = file->private_data;
 380         struct hiddev *hiddev = list->hiddev;
 381         struct hid_device *hid = hiddev->hid;
 382         struct usb_device *dev = hid->dev;
 383         struct hiddev_collection_info cinfo;
 384         struct hiddev_report_info rinfo;
 385         struct hiddev_field_info finfo;
 386         struct hiddev_usage_ref_multi *uref_multi=NULL;
 387         struct hiddev_usage_ref *uref;
 388         struct hiddev_devinfo dinfo;
 389         struct hid_report *report;
 390         struct hid_field *field;
 391         void __user *user_arg = (void __user *)arg;
 392         int i;
 393
 394         if (!hiddev->exist)
 395                 return -EIO;
 396
 397         switch (cmd) {
 398
 399         case HIDIOCGVERSION:
 400                 return put_user(HID_VERSION, (int __user *)arg);
 401
 402         case HIDIOCAPPLICATION:
 403                 if (arg < 0 || arg >= hid->maxapplication)
 404                         return -EINVAL;
 405
 406                 for (i = 0; i < hid->maxcollection; i++)
 407                         if (hid->collection[i].type ==
 408                             HID_COLLECTION_APPLICATION && arg-- == 0)
 409                                 break;
 410
 411                 if (i == hid->maxcollection)
 412                         return -EINVAL;
 413
 414                 return hid->collection[i].usage;
 415
 416         case HIDIOCGDEVINFO:
 417                 dinfo.bustype = BUS_USB;
 418                 dinfo.busnum = dev->bus->busnum;
 419                 dinfo.devnum = dev->devnum;
 420                 dinfo.ifnum = hid->ifnum;
 421                 dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
 422                 dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
 423                 dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
 424                 dinfo.num_applications = hid->maxapplication;
 425                 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
 426                         return -EFAULT;
 427
 428                 return 0;
 429
 430         case HIDIOCGFLAG:
 431                 if (put_user(list->flags, (int __user *)arg))
 432                         return -EFAULT;
 433
 434                 return 0;
 435
 436         case HIDIOCSFLAG:
 437                 {
 438                         int newflags;
 439                         if (get_user(newflags, (int __user *)arg))
 440                                 return -EFAULT;
 441
 442                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
 443                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
 444                              (newflags & HIDDEV_FLAG_UREF) == 0))
 445                                 return -EINVAL;
 446
 447                         list->flags = newflags;
 448
 449                         return 0;
 450                 }
 451
 452         case HIDIOCGSTRING:
 453                 {
 454                         int idx, len;
 455                         char *buf;
 456
 457                         if (get_user(idx, (int __user *)arg))
 458                                 return -EFAULT;
 459
 460                         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
 461                                 return -ENOMEM;
 462
 463                         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
 464                                 kfree(buf);
 465                                 return -EINVAL;
 466                         }
 467
 468                         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
 469                                 kfree(buf);
 470                                 return -EFAULT;
 471                         }
 472
 473                         kfree(buf);
 474
 475                         return len;
 476                 }
 477
 478         case HIDIOCINITREPORT:
 479                 hid_init_reports(hid);
 480
 481                 return 0;
 482
 483         case HIDIOCGREPORT:
 484                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
 485                         return -EFAULT;
 486
 487                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
 488                         return -EINVAL;
 489
 490                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 491                         return -EINVAL;
 492
 493                 hid_submit_report(hid, report, USB_DIR_IN);
 494                 hid_wait_io(hid);
 495
 496                 return 0;
 497
 498         case HIDIOCSREPORT:
 499                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
 500                         return -EFAULT;
 501
 502                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
 503                         return -EINVAL;
 504
 505                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 506                         return -EINVAL;
 507
 508                 hid_submit_report(hid, report, USB_DIR_OUT);
 509                 hid_wait_io(hid);
 510
 511                 return 0;
 512
 513         case HIDIOCGREPORTINFO:
 514                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
 515                         return -EFAULT;
 516
 517                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 518                         return -EINVAL;
 519
 520                 rinfo.num_fields = report->maxfield;
 521
 522                 if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
 523                         return -EFAULT;
 524
 525                 return 0;
 526
 527         case HIDIOCGFIELDINFO:
 528                 if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
 529                         return -EFAULT;
 530                 rinfo.report_type = finfo.report_type;
 531                 rinfo.report_id = finfo.report_id;
 532                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 533                         return -EINVAL;
 534
 535                 if (finfo.field_index >= report->maxfield)
 536                         return -EINVAL;
 537
 538                 field = report->field[finfo.field_index];
 539                 memset(&finfo, 0, sizeof(finfo));
 540                 finfo.report_type = rinfo.report_type;
 541                 finfo.report_id = rinfo.report_id;
 542                 finfo.field_index = field->report_count - 1;
 543                 finfo.maxusage = field->maxusage;
 544                 finfo.flags = field->flags;
 545                 finfo.physical = field->physical;
 546                 finfo.logical = field->logical;
 547                 finfo.application = field->application;
 548                 finfo.logical_minimum = field->logical_minimum;
 549                 finfo.logical_maximum = field->logical_maximum;
 550                 finfo.physical_minimum = field->physical_minimum;
 551                 finfo.physical_maximum = field->physical_maximum;
 552                 finfo.unit_exponent = field->unit_exponent;
 553                 finfo.unit = field->unit;
 554
 555                 if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
 556                         return -EFAULT;
 557
 558                 return 0;
 559
 560         case HIDIOCGUCODE:
 561                 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
 562                 if (!uref_multi)
 563                         return -ENOMEM;
 564                 uref = &uref_multi->uref;
 565                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
 566                         goto fault;
 567
 568                 rinfo.report_type = uref->report_type;
 569                 rinfo.report_id = uref->report_id;
 570                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 571                         goto inval;
 572
 573                 if (uref->field_index >= report->maxfield)
 574                         goto inval;
 575
 576                 field = report->field[uref->field_index];
 577                 if (uref->usage_index >= field->maxusage)
 578                         goto inval;
 579
 580                 uref->usage_code = field->usage[uref->usage_index].hid;
 581
 582                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
 583                         goto fault;
 584
 585                 kfree(uref_multi);
 586                 return 0;
 587
 588         case HIDIOCGUSAGE:
 589         case HIDIOCSUSAGE:
 590         case HIDIOCGUSAGES:
 591         case HIDIOCSUSAGES:
 592         case HIDIOCGCOLLECTIONINDEX:
 593                 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
 594                 if (!uref_multi)
 595                         return -ENOMEM;
 596                 uref = &uref_multi->uref;
 597                 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
 598                         if (copy_from_user(uref_multi, user_arg,
 599                                            sizeof(*uref_multi)))
 600                                 goto fault;
 601                 } else {
 602                         if (copy_from_user(uref, user_arg, sizeof(*uref)))
 603                                 goto fault;
 604                 }
 605
 606                 if (cmd != HIDIOCGUSAGE &&
 607                     cmd != HIDIOCGUSAGES &&
 608                     uref->report_type == HID_REPORT_TYPE_INPUT)
 609                         goto inval;
 610
 611                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
 612                         field = hiddev_lookup_usage(hid, uref);
 613                         if (field == NULL)
 614                                 goto inval;
 615                 } else {
 616                         rinfo.report_type = uref->report_type;
 617                         rinfo.report_id = uref->report_id;
 618                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 619                                 goto inval;
 620
 621                         if (uref->field_index >= report->maxfield)
 622                                 goto inval;
 623
 624                         field = report->field[uref->field_index];
 625
 626                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
 627                                 if (uref->usage_index >= field->maxusage)
 628                                         goto inval;
 629                         } else if (uref->usage_index >= field->report_count)
 630                                 goto inval;
 631
 632                         else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
 633                                  (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
 634                                   uref->usage_index + uref_multi->num_values > field->report_count))
 635                                 goto inval;
 636                         }
 637
 638                 switch (cmd) {
 639                         case HIDIOCGUSAGE:
 640                                 uref->value = field->value[uref->usage_index];
 641                                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
 642                                         goto fault;
 643                                 goto goodreturn;
 644
 645                         case HIDIOCSUSAGE:
 646                                 field->value[uref->usage_index] = uref->value;
 647                                 goto goodreturn;
 648
 649                         case HIDIOCGCOLLECTIONINDEX:
 650                                 kfree(uref_multi);
 651                                 return field->usage[uref->usage_index].collection_index;
 652                         case HIDIOCGUSAGES:
 653                                 for (i = 0; i < uref_multi->num_values; i++)
 654                                         uref_multi->values[i] =
 655                                             field->value[uref->usage_index + i];
 656                                 if (copy_to_user(user_arg, uref_multi,
 657                                                  sizeof(*uref_multi)))
 658                                         goto fault;
 659                                 goto goodreturn;
 660                         case HIDIOCSUSAGES:
 661                                 for (i = 0; i < uref_multi->num_values; i++)
 662                                         field->value[uref->usage_index + i] =
 663                                             uref_multi->values[i];
 664                                 goto goodreturn;
 665                 }
 666
 667 goodreturn:
 668                 kfree(uref_multi);
 669                 return 0;
 670 fault:
 671                 kfree(uref_multi);
 672                 return -EFAULT;
 673 inval:
 674                 kfree(uref_multi);
 675                 return -EINVAL;
 676
 677         case HIDIOCGCOLLECTIONINFO:
 678                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
 679                         return -EFAULT;
 680
 681                 if (cinfo.index >= hid->maxcollection)
 682                         return -EINVAL;
 683
 684                 cinfo.type = hid->collection[cinfo.index].type;
 685                 cinfo.usage = hid->collection[cinfo.index].usage;
 686                 cinfo.level = hid->collection[cinfo.index].level;
 687
 688                 if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
 689                         return -EFAULT;
 690                 return 0;
 691
 692         default:
 693
 694                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
 695                         return -EINVAL;
 696
 697                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
 698                         int len;
 699                         if (!hid->name)
 700                                 return 0;
 701                         len = strlen(hid->name) + 1;
 702                         if (len > _IOC_SIZE(cmd))
 703                                  len = _IOC_SIZE(cmd);
 704                         return copy_to_user(user_arg, hid->name, len) ?
 705                                 -EFAULT : len;
 706                 }
 707
 708                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
 709                         int len;
 710                         if (!hid->phys)
 711                                 return 0;
 712                         len = strlen(hid->phys) + 1;
 713                         if (len > _IOC_SIZE(cmd))
 714                                 len = _IOC_SIZE(cmd);
 715                         return copy_to_user(user_arg, hid->phys, len) ?
 716                                 -EFAULT : len;
 717                 }
 718         }
 719         return -EINVAL;
 720 }
 721
 722 static struct file_operations hiddev_fops = {
 723         .owner =        THIS_MODULE,
 724         .read =         hiddev_read,
 725         .write =        hiddev_write,
 726         .poll =         hiddev_poll,
 727         .open =         hiddev_open,
 728         .release =      hiddev_release,
 729         .ioctl =        hiddev_ioctl,
 730         .fasync =       hiddev_fasync,
 731 };
 732
 733 static struct usb_class_driver hiddev_class = {
 734         .name =         "hiddev%d",
 735         .fops =         &hiddev_fops,
 736         .minor_base =   HIDDEV_MINOR_BASE,
 737 };
 738
 739 /*
 740  * This is where hid.c calls us to connect a hid device to the hiddev driver
 741  */
 742 int hiddev_connect(struct hid_device *hid)
 743 {
 744         struct hiddev *hiddev;
 745         int i;
 746         int retval;
 747
 748         for (i = 0; i < hid->maxcollection; i++)
 749                 if (hid->collection[i].type ==
 750                     HID_COLLECTION_APPLICATION &&
 751                     !IS_INPUT_APPLICATION(hid->collection[i].usage))
 752                         break;
 753
 754         if (i == hid->maxcollection && (hid->quirks & HID_QUIRK_HIDDEV) == 0)
 755                 return -1;
 756
 757         if (!(hiddev = kmalloc(sizeof(struct hiddev), GFP_KERNEL)))
 758                 return -1;
 759         memset(hiddev, 0, sizeof(struct hiddev));
 760
 761         retval = usb_register_dev(hid->intf, &hiddev_class);
 762         if (retval) {
 763                 err("Not able to get a minor for this device.");
 764                 kfree(hiddev);
 765                 return -1;
 766         }
 767
 768         init_waitqueue_head(&hiddev->wait);
 769
 770         hiddev_table[hid->intf->minor - HIDDEV_MINOR_BASE] = hiddev;
 771
 772         hiddev->hid = hid;
 773         hiddev->exist = 1;
 774
 775         hid->minor = hid->intf->minor;
 776         hid->hiddev = hiddev;
 777
 778         return 0;
 779 }
 780
 781 /*
 782  * This is where hid.c calls us to disconnect a hiddev device from the
 783  * corresponding hid device (usually because the usb device has disconnected)
 784  */
 785 static struct usb_class_driver hiddev_class;
 786 void hiddev_disconnect(struct hid_device *hid)
 787 {
 788         struct hiddev *hiddev = hid->hiddev;
 789
 790         hiddev->exist = 0;
 791
 792         hiddev_table[hiddev->hid->minor - HIDDEV_MINOR_BASE] = NULL;
 793         usb_deregister_dev(hiddev->hid->intf, &hiddev_class);
 794
 795         if (hiddev->open) {
 796                 hid_close(hiddev->hid);
 797                 wake_up_interruptible(&hiddev->wait);
 798         } else {
 799                 kfree(hiddev);
 800         }
 801 }
 802
 803 /* Currently this driver is a USB driver.  It's not a conventional one in
 804  * the sense that it doesn't probe at the USB level.  Instead it waits to
 805  * be connected by HID through the hiddev_connect / hiddev_disconnect
 806  * routines.  The reason to register as a USB device is to gain part of the
 807  * minor number space from the USB major.
 808  *
 809  * In theory, should the HID code be generalized to more than one physical
 810  * medium (say, IEEE 1384), this driver will probably need to register its
 811  * own major number, and in doing so, no longer need to register with USB.
 812  * At that point the probe routine and hiddev_driver struct below will no
 813  * longer be useful.
 814  */
 815
 816
 817 /* We never attach in this manner, and rely on HID to connect us.  This
 818  * is why there is no disconnect routine defined in the usb_driver either.
 819  */
 820 static int hiddev_usbd_probe(struct usb_interface *intf,
 821                              const struct usb_device_id *hiddev_info)
 822 {
 823         return -ENODEV;
 824 }
 825
 826
 827 static /* const */ struct usb_driver hiddev_driver = {
 828         .name =         "hiddev",
 829         .probe =        hiddev_usbd_probe,
 830 };
 831
 832 int __init hiddev_init(void)
 833 {
 834         return usb_register(&hiddev_driver);
 835 }
 836
 837 void hiddev_exit(void)
 838 {
 839         usb_deregister(&hiddev_driver);
 840 }