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 #include <linux/devfs_fs_kernel.h>
  39
  40 #ifdef CONFIG_USB_DYNAMIC_MINORS
  41 #define HIDDEV_MINOR_BASE       0
  42 #define HIDDEV_MINORS           256
  43 #else
  44 #define HIDDEV_MINOR_BASE       96
  45 #define HIDDEV_MINORS           16
  46 #endif
  47 #define HIDDEV_BUFFER_SIZE      64
  48
  49 struct hiddev {
  50         int exist;
  51         int open;
  52         wait_queue_head_t wait;
  53         struct hid_device *hid;
  54         struct hiddev_list *list;
  55 };
  56
  57 struct hiddev_list {
  58         struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
  59         int head;
  60         int tail;
  61         unsigned flags;
  62         struct fasync_struct *fasync;
  63         struct hiddev *hiddev;
  64         struct hiddev_list *next;
  65 };
  66
  67 static struct hiddev *hiddev_table[HIDDEV_MINORS];
  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 flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
  79         struct hid_report_enum *report_enum;
  80         struct list_head *list;
  81
  82         if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
  83             rinfo->report_type > HID_REPORT_TYPE_MAX) return NULL;
  84
  85         report_enum = hid->report_enum +
  86                 (rinfo->report_type - HID_REPORT_TYPE_MIN);
  87
  88         switch (flags) {
  89         case 0: /* Nothing to do -- report_id is already set correctly */
  90                 break;
  91
  92         case HID_REPORT_ID_FIRST:
  93                 list = report_enum->report_list.next;
  94                 if (list == &report_enum->report_list)
  95                         return NULL;
  96                 rinfo->report_id = ((struct hid_report *) list)->id;
  97                 break;
  98
  99         case HID_REPORT_ID_NEXT:
 100                 list = (struct list_head *)
 101                         report_enum->report_id_hash[rinfo->report_id & HID_REPORT_ID_MASK];
 102                 if (list == NULL)
 103                         return NULL;
 104                 list = list->next;
 105                 if (list == &report_enum->report_list)
 106                         return NULL;
 107                 rinfo->report_id = ((struct hid_report *) list)->id;
 108                 break;
 109
 110         default:
 111                 return NULL;
 112         }
 113
 114         return report_enum->report_id_hash[rinfo->report_id];
 115 }
 116
 117 /*
 118  * Perform an exhaustive search of the report table for a usage, given its
 119  * type and usage id.
 120  */
 121 static struct hid_field *
 122 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
 123 {
 124         int i, j;
 125         struct hid_report *report;
 126         struct hid_report_enum *report_enum;
 127         struct list_head *list;
 128         struct hid_field *field;
 129
 130         if (uref->report_type < HID_REPORT_TYPE_MIN ||
 131             uref->report_type > HID_REPORT_TYPE_MAX) return NULL;
 132
 133         report_enum = hid->report_enum +
 134                 (uref->report_type - HID_REPORT_TYPE_MIN);
 135         list = report_enum->report_list.next;
 136         while (list != &report_enum->report_list) {
 137                 report = (struct hid_report *) list;
 138                 for (i = 0; i < report->maxfield; i++) {
 139                         field = report->field[i];
 140                         for (j = 0; j < field->maxusage; j++) {
 141                                 if (field->usage[j].hid == uref->usage_code) {
 142                                         uref->report_id = report->id;
 143                                         uref->field_index = i;
 144                                         uref->usage_index = j;
 145                                         return field;
 146                                 }
 147                         }
 148                 }
 149                 list = list->next;
 150         }
 151
 152         return NULL;
 153 }
 154
 155 static void hiddev_send_event(struct hid_device *hid,
 156                               struct hiddev_usage_ref *uref)
 157 {
 158         struct hiddev *hiddev = hid->hiddev;
 159         struct hiddev_list *list = hiddev->list;
 160
 161         while (list) {
 162                 if (uref->field_index != HID_FIELD_INDEX_NONE ||
 163                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 164                         list->buffer[list->head] = *uref;
 165                         list->head = (list->head + 1) &
 166                                 (HIDDEV_BUFFER_SIZE - 1);
 167                         kill_fasync(&list->fasync, SIGIO, POLL_IN);
 168                 }
 169
 170                 list = list->next;
 171         }
 172
 173         wake_up_interruptible(&hiddev->wait);
 174 }
 175
 176 /*
 177  * This is where hid.c calls into hiddev to pass an event that occurred over
 178  * the interrupt pipe
 179  */
 180 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
 181                       struct hid_usage *usage, __s32 value, struct pt_regs *regs)
 182 {
 183         unsigned type = field->report_type;
 184         struct hiddev_usage_ref uref;
 185
 186         uref.report_type =
 187           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
 188           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
 189            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE:0));
 190         uref.report_id = field->report->id;
 191         uref.field_index = field->index;
 192         uref.usage_index = (usage - field->usage);
 193         uref.usage_code = usage->hid;
 194         uref.value = value;
 195
 196         hiddev_send_event(hid, &uref);
 197 }
 198
 199
 200 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
 201 {
 202         unsigned type = report->type;
 203         struct hiddev_usage_ref uref;
 204
 205         memset(&uref, 0, sizeof(uref));
 206         uref.report_type =
 207           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
 208           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
 209            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE:0));
 210         uref.report_id = report->id;
 211         uref.field_index = HID_FIELD_INDEX_NONE;
 212
 213         hiddev_send_event(hid, &uref);
 214 }
 215 /*
 216  * fasync file op
 217  */
 218 static int hiddev_fasync(int fd, struct file *file, int on)
 219 {
 220         int retval;
 221         struct hiddev_list *list = file->private_data;
 222         retval = fasync_helper(fd, file, on, &list->fasync);
 223         return retval < 0 ? retval : 0;
 224 }
 225
 226
 227 /*
 228  * release file op
 229  */
 230 static int hiddev_release(struct inode * inode, struct file * file)
 231 {
 232         struct hiddev_list *list = file->private_data;
 233         struct hiddev_list **listptr;
 234
 235         listptr = &list->hiddev->list;
 236         hiddev_fasync(-1, file, 0);
 237
 238         while (*listptr && (*listptr != list))
 239                 listptr = &((*listptr)->next);
 240         *listptr = (*listptr)->next;
 241
 242         if (!--list->hiddev->open) {
 243                 if (list->hiddev->exist)
 244                         hid_close(list->hiddev->hid);
 245                 else
 246                         kfree(list->hiddev);
 247         }
 248
 249         kfree(list);
 250
 251         return 0;
 252 }
 253
 254 /*
 255  * open file op
 256  */
 257 static int hiddev_open(struct inode * inode, struct file * file) {
 258         struct hiddev_list *list;
 259
 260         int i = iminor(inode) - HIDDEV_MINOR_BASE;
 261
 262         if (i >= HIDDEV_MINORS || !hiddev_table[i])
 263                 return -ENODEV;
 264
 265         if (!(list = kmalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
 266                 return -ENOMEM;
 267         memset(list, 0, sizeof(struct hiddev_list));
 268
 269         list->hiddev = hiddev_table[i];
 270         list->next = hiddev_table[i]->list;
 271         hiddev_table[i]->list = list;
 272
 273         file->private_data = list;
 274
 275         if (!list->hiddev->open++)
 276                 if (list->hiddev->exist)
 277                         hid_open(hiddev_table[i]->hid);
 278
 279         return 0;
 280 }
 281
 282 /*
 283  * "write" file op
 284  */
 285 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
 286 {
 287         return -EINVAL;
 288 }
 289
 290 /*
 291  * "read" file op
 292  */
 293 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
 294 {
 295         DECLARE_WAITQUEUE(wait, current);
 296         struct hiddev_list *list = file->private_data;
 297         int event_size;
 298         int retval = 0;
 299
 300         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
 301                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
 302
 303         if (count < event_size)
 304                 return 0;
 305
 306         while (retval == 0) {
 307                 if (list->head == list->tail) {
 308                         add_wait_queue(&list->hiddev->wait, &wait);
 309                         set_current_state(TASK_INTERRUPTIBLE);
 310
 311                         while (list->head == list->tail) {
 312                                 if (file->f_flags & O_NONBLOCK) {
 313                                         retval = -EAGAIN;
 314                                         break;
 315                                 }
 316                                 if (signal_pending(current)) {
 317                                         retval = -ERESTARTSYS;
 318                                         break;
 319                                 }
 320                                 if (!list->hiddev->exist) {
 321                                         retval = -EIO;
 322                                         break;
 323                                 }
 324
 325                                 schedule();
 326                         }
 327
 328                         set_current_state(TASK_RUNNING);
 329                         remove_wait_queue(&list->hiddev->wait, &wait);
 330                 }
 331
 332                 if (retval)
 333                         return retval;
 334
 335
 336                 while (list->head != list->tail &&
 337                        retval + event_size <= count) {
 338                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
 339                                 if (list->buffer[list->tail].field_index !=
 340                                     HID_FIELD_INDEX_NONE) {
 341                                         struct hiddev_event event;
 342                                         event.hid = list->buffer[list->tail].usage_code;
 343                                         event.value = list->buffer[list->tail].value;
 344                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event)))
 345                                                 return -EFAULT;
 346                                         retval += sizeof(struct hiddev_event);
 347                                 }
 348                         } else {
 349                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
 350                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 351                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref)))
 352                                                 return -EFAULT;
 353                                         retval += sizeof(struct hiddev_usage_ref);
 354                                 }
 355                         }
 356                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
 357                 }
 358
 359         }
 360
 361         return retval;
 362 }
 363
 364 /*
 365  * "poll" file op
 366  * No kernel lock - fine
 367  */
 368 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
 369 {
 370         struct hiddev_list *list = file->private_data;
 371         poll_wait(file, &list->hiddev->wait, wait);
 372         if (list->head != list->tail)
 373                 return POLLIN | POLLRDNORM;
 374         if (!list->hiddev->exist)
 375                 return POLLERR | POLLHUP;
 376         return 0;
 377 }
 378
 379 /*
 380  * "ioctl" file op
 381  */
 382 static int hiddev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 383 {
 384         struct hiddev_list *list = file->private_data;
 385         struct hiddev *hiddev = list->hiddev;
 386         struct hid_device *hid = hiddev->hid;
 387         struct usb_device *dev = hid->dev;
 388         struct hiddev_collection_info cinfo;
 389         struct hiddev_report_info rinfo;
 390         struct hiddev_field_info finfo;
 391         struct hiddev_usage_ref_multi *uref_multi=NULL;
 392         struct hiddev_usage_ref *uref;
 393         struct hiddev_devinfo dinfo;
 394         struct hid_report *report;
 395         struct hid_field *field;
 396         void __user *user_arg = (void __user *)arg;
 397         int i;
 398
 399         if (!hiddev->exist)
 400                 return -EIO;
 401
 402         switch (cmd) {
 403
 404         case HIDIOCGVERSION:
 405                 return put_user(HID_VERSION, (int __user *)arg);
 406
 407         case HIDIOCAPPLICATION:
 408                 if (arg < 0 || arg >= hid->maxapplication)
 409                         return -EINVAL;
 410
 411                 for (i = 0; i < hid->maxcollection; i++)
 412                         if (hid->collection[i].type ==
 413                             HID_COLLECTION_APPLICATION && arg-- == 0)
 414                                 break;
 415
 416                 if (i == hid->maxcollection)
 417                         return -EINVAL;
 418
 419                 return hid->collection[i].usage;
 420
 421         case HIDIOCGDEVINFO:
 422                 dinfo.bustype = BUS_USB;
 423                 dinfo.busnum = dev->bus->busnum;
 424                 dinfo.devnum = dev->devnum;
 425                 dinfo.ifnum = hid->ifnum;
 426                 dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
 427                 dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
 428                 dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
 429                 dinfo.num_applications = hid->maxapplication;
 430                 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
 431                         return -EFAULT;
 432
 433                 return 0;
 434
 435         case HIDIOCGFLAG:
 436                 if (put_user(list->flags, (int __user *)arg))
 437                         return -EFAULT;
 438
 439                 return 0;
 440
 441         case HIDIOCSFLAG:
 442                 {
 443                         int newflags;
 444                         if (get_user(newflags, (int __user *)arg))
 445                                 return -EFAULT;
 446
 447                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
 448                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
 449                              (newflags & HIDDEV_FLAG_UREF) == 0))
 450                                 return -EINVAL;
 451
 452                         list->flags = newflags;
 453
 454                         return 0;
 455                 }
 456
 457         case HIDIOCGSTRING:
 458                 {
 459                         int idx, len;
 460                         char *buf;
 461
 462                         if (get_user(idx, (int __user *)arg))
 463                                 return -EFAULT;
 464
 465                         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
 466                                 return -ENOMEM;
 467
 468                         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
 469                                 kfree(buf);
 470                                 return -EINVAL;
 471                         }
 472
 473                         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
 474                                 kfree(buf);
 475                                 return -EFAULT;
 476                         }
 477
 478                         kfree(buf);
 479
 480                         return len;
 481                 }
 482
 483         case HIDIOCINITREPORT:
 484                 hid_init_reports(hid);
 485
 486                 return 0;
 487
 488         case HIDIOCGREPORT:
 489                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
 490                         return -EFAULT;
 491
 492                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
 493                         return -EINVAL;
 494
 495                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 496                         return -EINVAL;
 497
 498                 hid_submit_report(hid, report, USB_DIR_IN);
 499                 hid_wait_io(hid);
 500
 501                 return 0;
 502
 503         case HIDIOCSREPORT:
 504                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
 505                         return -EFAULT;
 506
 507                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
 508                         return -EINVAL;
 509
 510                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 511                         return -EINVAL;
 512
 513                 hid_submit_report(hid, report, USB_DIR_OUT);
 514
 515                 return 0;
 516
 517         case HIDIOCGREPORTINFO:
 518                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
 519                         return -EFAULT;
 520
 521                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 522                         return -EINVAL;
 523
 524                 rinfo.num_fields = report->maxfield;
 525
 526                 if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
 527                         return -EFAULT;
 528
 529                 return 0;
 530
 531         case HIDIOCGFIELDINFO:
 532                 if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
 533                         return -EFAULT;
 534                 rinfo.report_type = finfo.report_type;
 535                 rinfo.report_id = finfo.report_id;
 536                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 537                         return -EINVAL;
 538
 539                 if (finfo.field_index >= report->maxfield)
 540                         return -EINVAL;
 541
 542                 field = report->field[finfo.field_index];
 543                 memset(&finfo, 0, sizeof(finfo));
 544                 finfo.report_type = rinfo.report_type;
 545                 finfo.report_id = rinfo.report_id;
 546                 finfo.field_index = field->report_count - 1;
 547                 finfo.maxusage = field->maxusage;
 548                 finfo.flags = field->flags;
 549                 finfo.physical = field->physical;
 550                 finfo.logical = field->logical;
 551                 finfo.application = field->application;
 552                 finfo.logical_minimum = field->logical_minimum;
 553                 finfo.logical_maximum = field->logical_maximum;
 554                 finfo.physical_minimum = field->physical_minimum;
 555                 finfo.physical_maximum = field->physical_maximum;
 556                 finfo.unit_exponent = field->unit_exponent;
 557                 finfo.unit = field->unit;
 558
 559                 if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
 560                         return -EFAULT;
 561
 562                 return 0;
 563
 564         case HIDIOCGUCODE:
 565                 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
 566                 if (!uref_multi)
 567                         return -ENOMEM;
 568                 uref = &uref_multi->uref;
 569                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
 570                         goto fault;
 571
 572                 rinfo.report_type = uref->report_type;
 573                 rinfo.report_id = uref->report_id;
 574                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 575                         goto inval;
 576
 577                 if (uref->field_index >= report->maxfield)
 578                         goto inval;
 579
 580                 field = report->field[uref->field_index];
 581                 if (uref->usage_index >= field->maxusage)
 582                         goto inval;
 583
 584                 uref->usage_code = field->usage[uref->usage_index].hid;
 585
 586                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
 587                         goto fault;
 588
 589                 kfree(uref_multi);
 590                 return 0;
 591
 592         case HIDIOCGUSAGE:
 593         case HIDIOCSUSAGE:
 594         case HIDIOCGUSAGES:
 595         case HIDIOCSUSAGES:
 596         case HIDIOCGCOLLECTIONINDEX:
 597                 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
 598                 if (!uref_multi)
 599                         return -ENOMEM;
 600                 uref = &uref_multi->uref;
 601                 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
 602                         if (copy_from_user(uref_multi, user_arg,
 603                                            sizeof(*uref_multi)))
 604                                 goto fault;
 605                 } else {
 606                         if (copy_from_user(uref, user_arg, sizeof(*uref)))
 607                                 goto fault;
 608                 }
 609
 610                 if (cmd != HIDIOCGUSAGE &&
 611                     cmd != HIDIOCGUSAGES &&
 612                     uref->report_type == HID_REPORT_TYPE_INPUT)
 613                         goto inval;
 614
 615                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
 616                         field = hiddev_lookup_usage(hid, uref);
 617                         if (field == NULL)
 618                                 goto inval;
 619                 } else {
 620                         rinfo.report_type = uref->report_type;
 621                         rinfo.report_id = uref->report_id;
 622                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 623                                 goto inval;
 624
 625                         if (uref->field_index >= report->maxfield)
 626                                 goto inval;
 627
 628                         field = report->field[uref->field_index];
 629
 630                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
 631                                 if (uref->usage_index >= field->maxusage)
 632                                         goto inval;
 633                         } else if (uref->usage_index >= field->report_count)
 634                                 goto inval;
 635
 636                         else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
 637                                  (uref_multi->num_values >= HID_MAX_MULTI_USAGES ||
 638                                   uref->usage_index + uref_multi->num_values >= field->report_count ||
 639                                   uref->usage_index + uref_multi->num_values < uref->usage_index))
 640                                 goto inval;
 641                         }
 642
 643                 switch (cmd) {
 644                         case HIDIOCGUSAGE:
 645                                 uref->value = field->value[uref->usage_index];
 646                                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
 647                                         goto fault;
 648                                 goto goodreturn;
 649
 650                         case HIDIOCSUSAGE:
 651                                 field->value[uref->usage_index] = uref->value;
 652                                 goto goodreturn;
 653
 654                         case HIDIOCGCOLLECTIONINDEX:
 655                                 kfree(uref_multi);
 656                                 return field->usage[uref->usage_index].collection_index;
 657                         case HIDIOCGUSAGES:
 658                                 for (i = 0; i < uref_multi->num_values; i++)
 659                                         uref_multi->values[i] =
 660                                             field->value[uref->usage_index + i];
 661                                 if (copy_to_user(user_arg, uref_multi,
 662                                                  sizeof(*uref_multi)))
 663                                         goto fault;
 664                                 goto goodreturn;
 665                         case HIDIOCSUSAGES:
 666                                 for (i = 0; i < uref_multi->num_values; i++)
 667                                         field->value[uref->usage_index + i] =
 668                                             uref_multi->values[i];
 669                                 goto goodreturn;
 670                 }
 671
 672 goodreturn:
 673                 kfree(uref_multi);
 674                 return 0;
 675 fault:
 676                 kfree(uref_multi);
 677                 return -EFAULT;
 678 inval:
 679                 kfree(uref_multi);
 680                 return -EINVAL;
 681
 682         case HIDIOCGCOLLECTIONINFO:
 683                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
 684                         return -EFAULT;
 685
 686                 if (cinfo.index >= hid->maxcollection)
 687                         return -EINVAL;
 688
 689                 cinfo.type = hid->collection[cinfo.index].type;
 690                 cinfo.usage = hid->collection[cinfo.index].usage;
 691                 cinfo.level = hid->collection[cinfo.index].level;
 692
 693                 if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
 694                         return -EFAULT;
 695                 return 0;
 696
 697         default:
 698
 699                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
 700                         return -EINVAL;
 701
 702                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
 703                         int len;
 704                         if (!hid->name)
 705                                 return 0;
 706                         len = strlen(hid->name) + 1;
 707                         if (len > _IOC_SIZE(cmd))
 708                                  len = _IOC_SIZE(cmd);
 709                         return copy_to_user(user_arg, hid->name, len) ?
 710                                 -EFAULT : len;
 711                 }
 712
 713                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
 714                         int len;
 715                         if (!hid->phys)
 716                                 return 0;
 717                         len = strlen(hid->phys) + 1;
 718                         if (len > _IOC_SIZE(cmd))
 719                                 len = _IOC_SIZE(cmd);
 720                         return copy_to_user(user_arg, hid->phys, len) ?
 721                                 -EFAULT : len;
 722                 }
 723         }
 724         return -EINVAL;
 725 }
 726
 727 static struct file_operations hiddev_fops = {
 728         .owner =        THIS_MODULE,
 729         .read =         hiddev_read,
 730         .write =        hiddev_write,
 731         .poll =         hiddev_poll,
 732         .open =         hiddev_open,
 733         .release =      hiddev_release,
 734         .ioctl =        hiddev_ioctl,
 735         .fasync =       hiddev_fasync,
 736 };
 737
 738 static struct usb_class_driver hiddev_class = {
 739         .name =         "usb/hid/hiddev%d",
 740         .fops =         &hiddev_fops,
 741         .mode =         S_IFCHR | S_IRUGO | S_IWUSR,
 742         .minor_base =   HIDDEV_MINOR_BASE,
 743 };
 744
 745 /*
 746  * This is where hid.c calls us to connect a hid device to the hiddev driver
 747  */
 748 int hiddev_connect(struct hid_device *hid)
 749 {
 750         struct hiddev *hiddev;
 751         int i;
 752         int retval;
 753
 754         for (i = 0; i < hid->maxcollection; i++)
 755                 if (hid->collection[i].type ==
 756                     HID_COLLECTION_APPLICATION &&
 757                     !IS_INPUT_APPLICATION(hid->collection[i].usage))
 758                         break;
 759
 760         if (i == hid->maxcollection && (hid->quirks & HID_QUIRK_HIDDEV) == 0)
 761                 return -1;
 762
 763         if (!(hiddev = kmalloc(sizeof(struct hiddev), GFP_KERNEL)))
 764                 return -1;
 765         memset(hiddev, 0, sizeof(struct hiddev));
 766
 767         retval = usb_register_dev(hid->intf, &hiddev_class);
 768         if (retval) {
 769                 err("Not able to get a minor for this device.");
 770                 kfree(hiddev);
 771                 return -1;
 772         }
 773
 774         init_waitqueue_head(&hiddev->wait);
 775
 776         hiddev_table[hid->intf->minor - HIDDEV_MINOR_BASE] = hiddev;
 777
 778         hiddev->hid = hid;
 779         hiddev->exist = 1;
 780
 781         hid->minor = hid->intf->minor;
 782         hid->hiddev = hiddev;
 783
 784         return 0;
 785 }
 786
 787 /*
 788  * This is where hid.c calls us to disconnect a hiddev device from the
 789  * corresponding hid device (usually because the usb device has disconnected)
 790  */
 791 static struct usb_class_driver hiddev_class;
 792 void hiddev_disconnect(struct hid_device *hid)
 793 {
 794         struct hiddev *hiddev = hid->hiddev;
 795
 796         hiddev->exist = 0;
 797
 798         hiddev_table[hiddev->hid->minor - HIDDEV_MINOR_BASE] = NULL;
 799         usb_deregister_dev(hiddev->hid->intf, &hiddev_class);
 800
 801         if (hiddev->open) {
 802                 hid_close(hiddev->hid);
 803                 wake_up_interruptible(&hiddev->wait);
 804         } else {
 805                 kfree(hiddev);
 806         }
 807 }
 808
 809 /* Currently this driver is a USB driver.  It's not a conventional one in
 810  * the sense that it doesn't probe at the USB level.  Instead it waits to
 811  * be connected by HID through the hiddev_connect / hiddev_disconnect
 812  * routines.  The reason to register as a USB device is to gain part of the
 813  * minor number space from the USB major.
 814  *
 815  * In theory, should the HID code be generalized to more than one physical
 816  * medium (say, IEEE 1384), this driver will probably need to register its
 817  * own major number, and in doing so, no longer need to register with USB.
 818  * At that point the probe routine and hiddev_driver struct below will no
 819  * longer be useful.
 820  */
 821
 822
 823 /* We never attach in this manner, and rely on HID to connect us.  This
 824  * is why there is no disconnect routine defined in the usb_driver either.
 825  */
 826 static int hiddev_usbd_probe(struct usb_interface *intf,
 827                              const struct usb_device_id *hiddev_info)
 828 {
 829         return -ENODEV;
 830 }
 831
 832
 833 static /* const */ struct usb_driver hiddev_driver = {
 834         .owner =        THIS_MODULE,
 835         .name =         "hiddev",
 836         .probe =        hiddev_usbd_probe,
 837 };
 838
 839 int __init hiddev_init(void)
 840 {
 841         devfs_mk_dir("usb/hid");
 842         return usb_register(&hiddev_driver);
 843 }
 844
 845 void hiddev_exit(void)
 846 {
 847         usb_deregister(&hiddev_driver);
 848         devfs_remove("usb/hid");
 849 }