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  * De-allocate a hiddev structure
 228  */
 229 static struct usb_class_driver hiddev_class;
 230 static void hiddev_cleanup(struct hiddev *hiddev)
 231 {
 232         hiddev_table[hiddev->hid->minor - HIDDEV_MINOR_BASE] = NULL;
 233         usb_deregister_dev(hiddev->hid->intf, &hiddev_class);
 234         kfree(hiddev);
 235 }
 236
 237 /*
 238  * release file op
 239  */
 240 static int hiddev_release(struct inode * inode, struct file * file)
 241 {
 242         struct hiddev_list *list = file->private_data;
 243         struct hiddev_list **listptr;
 244
 245         listptr = &list->hiddev->list;
 246         hiddev_fasync(-1, file, 0);
 247
 248         while (*listptr && (*listptr != list))
 249                 listptr = &((*listptr)->next);
 250         *listptr = (*listptr)->next;
 251
 252         if (!--list->hiddev->open) {
 253                 if (list->hiddev->exist)
 254                         hid_close(list->hiddev->hid);
 255                 else
 256                         hiddev_cleanup(list->hiddev);
 257         }
 258
 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         struct hiddev_list *list;
 269
 270         int i = iminor(inode) - HIDDEV_MINOR_BASE;
 271
 272         if (i >= HIDDEV_MINORS || !hiddev_table[i])
 273                 return -ENODEV;
 274
 275         if (!(list = kmalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
 276                 return -ENOMEM;
 277         memset(list, 0, sizeof(struct hiddev_list));
 278
 279         list->hiddev = hiddev_table[i];
 280         list->next = hiddev_table[i]->list;
 281         hiddev_table[i]->list = list;
 282
 283         file->private_data = list;
 284
 285         if (!list->hiddev->open++)
 286                 if (list->hiddev->exist)
 287                         hid_open(hiddev_table[i]->hid);
 288
 289         return 0;
 290 }
 291
 292 /*
 293  * "write" file op
 294  */
 295 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
 296 {
 297         return -EINVAL;
 298 }
 299
 300 /*
 301  * "read" file op
 302  */
 303 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
 304 {
 305         DECLARE_WAITQUEUE(wait, current);
 306         struct hiddev_list *list = file->private_data;
 307         int event_size;
 308         int retval = 0;
 309
 310         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
 311                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
 312
 313         if (count < event_size)
 314                 return 0;
 315
 316         while (retval == 0) {
 317                 if (list->head == list->tail) {
 318                         add_wait_queue(&list->hiddev->wait, &wait);
 319                         set_current_state(TASK_INTERRUPTIBLE);
 320
 321                         while (list->head == list->tail) {
 322                                 if (file->f_flags & O_NONBLOCK) {
 323                                         retval = -EAGAIN;
 324                                         break;
 325                                 }
 326                                 if (signal_pending(current)) {
 327                                         retval = -ERESTARTSYS;
 328                                         break;
 329                                 }
 330                                 if (!list->hiddev->exist) {
 331                                         retval = -EIO;
 332                                         break;
 333                                 }
 334
 335                                 schedule();
 336                         }
 337
 338                         set_current_state(TASK_RUNNING);
 339                         remove_wait_queue(&list->hiddev->wait, &wait);
 340                 }
 341
 342                 if (retval)
 343                         return retval;
 344
 345
 346                 while (list->head != list->tail &&
 347                        retval + event_size <= count) {
 348                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
 349                                 if (list->buffer[list->tail].field_index !=
 350                                     HID_FIELD_INDEX_NONE) {
 351                                         struct hiddev_event event;
 352                                         event.hid = list->buffer[list->tail].usage_code;
 353                                         event.value = list->buffer[list->tail].value;
 354                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event)))
 355                                                 return -EFAULT;
 356                                         retval += sizeof(struct hiddev_event);
 357                                 }
 358                         } else {
 359                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
 360                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 361                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref)))
 362                                                 return -EFAULT;
 363                                         retval += sizeof(struct hiddev_usage_ref);
 364                                 }
 365                         }
 366                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
 367                 }
 368
 369         }
 370
 371         return retval;
 372 }
 373
 374 /*
 375  * "poll" file op
 376  * No kernel lock - fine
 377  */
 378 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
 379 {
 380         struct hiddev_list *list = file->private_data;
 381         poll_wait(file, &list->hiddev->wait, wait);
 382         if (list->head != list->tail)
 383                 return POLLIN | POLLRDNORM;
 384         if (!list->hiddev->exist)
 385                 return POLLERR | POLLHUP;
 386         return 0;
 387 }
 388
 389 /*
 390  * "ioctl" file op
 391  */
 392 static int hiddev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
 393 {
 394         struct hiddev_list *list = file->private_data;
 395         struct hiddev *hiddev = list->hiddev;
 396         struct hid_device *hid = hiddev->hid;
 397         struct usb_device *dev = hid->dev;
 398         struct hiddev_collection_info cinfo;
 399         struct hiddev_report_info rinfo;
 400         struct hiddev_field_info finfo;
 401         struct hiddev_usage_ref_multi *uref_multi=NULL;
 402         struct hiddev_usage_ref *uref;
 403         struct hiddev_devinfo dinfo;
 404         struct hid_report *report;
 405         struct hid_field *field;
 406         void __user *user_arg = (void __user *)arg;
 407         int i;
 408
 409         if (!hiddev->exist)
 410                 return -EIO;
 411
 412         switch (cmd) {
 413
 414         case HIDIOCGVERSION:
 415                 return put_user(HID_VERSION, (int __user *)arg);
 416
 417         case HIDIOCAPPLICATION:
 418                 if (arg < 0 || arg >= hid->maxapplication)
 419                         return -EINVAL;
 420
 421                 for (i = 0; i < hid->maxcollection; i++)
 422                         if (hid->collection[i].type ==
 423                             HID_COLLECTION_APPLICATION && arg-- == 0)
 424                                 break;
 425
 426                 if (i == hid->maxcollection)
 427                         return -EINVAL;
 428
 429                 return hid->collection[i].usage;
 430
 431         case HIDIOCGDEVINFO:
 432                 dinfo.bustype = BUS_USB;
 433                 dinfo.busnum = dev->bus->busnum;
 434                 dinfo.devnum = dev->devnum;
 435                 dinfo.ifnum = hid->ifnum;
 436                 dinfo.vendor = dev->descriptor.idVendor;
 437                 dinfo.product = dev->descriptor.idProduct;
 438                 dinfo.version = dev->descriptor.bcdDevice;
 439                 dinfo.num_applications = hid->maxapplication;
 440                 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
 441                         return -EFAULT;
 442
 443                 return 0;
 444
 445         case HIDIOCGFLAG:
 446                 if (put_user(list->flags, (int __user *)arg))
 447                         return -EFAULT;
 448
 449                 return 0;
 450
 451         case HIDIOCSFLAG:
 452                 {
 453                         int newflags;
 454                         if (get_user(newflags, (int __user *)arg))
 455                                 return -EFAULT;
 456
 457                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
 458                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
 459                              (newflags & HIDDEV_FLAG_UREF) == 0))
 460                                 return -EINVAL;
 461
 462                         list->flags = newflags;
 463
 464                         return 0;
 465                 }
 466
 467         case HIDIOCGSTRING:
 468                 {
 469                         int idx, len;
 470                         char *buf;
 471
 472                         if (get_user(idx, (int __user *)arg))
 473                                 return -EFAULT;
 474
 475                         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
 476                                 return -ENOMEM;
 477
 478                         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
 479                                 kfree(buf);
 480                                 return -EINVAL;
 481                         }
 482
 483                         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
 484                                 kfree(buf);
 485                                 return -EFAULT;
 486                         }
 487
 488                         kfree(buf);
 489
 490                         return len;
 491                 }
 492
 493         case HIDIOCINITREPORT:
 494                 hid_init_reports(hid);
 495
 496                 return 0;
 497
 498         case HIDIOCGREPORT:
 499                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
 500                         return -EFAULT;
 501
 502                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
 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_IN);
 509                 hid_wait_io(hid);
 510
 511                 return 0;
 512
 513         case HIDIOCSREPORT:
 514                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
 515                         return -EFAULT;
 516
 517                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
 518                         return -EINVAL;
 519
 520                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 521                         return -EINVAL;
 522
 523                 hid_submit_report(hid, report, USB_DIR_OUT);
 524
 525                 return 0;
 526
 527         case HIDIOCGREPORTINFO:
 528                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
 529                         return -EFAULT;
 530
 531                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 532                         return -EINVAL;
 533
 534                 rinfo.num_fields = report->maxfield;
 535
 536                 if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
 537                         return -EFAULT;
 538
 539                 return 0;
 540
 541         case HIDIOCGFIELDINFO:
 542                 if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
 543                         return -EFAULT;
 544                 rinfo.report_type = finfo.report_type;
 545                 rinfo.report_id = finfo.report_id;
 546                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 547                         return -EINVAL;
 548
 549                 if (finfo.field_index >= report->maxfield)
 550                         return -EINVAL;
 551
 552                 field = report->field[finfo.field_index];
 553                 memset(&finfo, 0, sizeof(finfo));
 554                 finfo.report_type = rinfo.report_type;
 555                 finfo.report_id = rinfo.report_id;
 556                 finfo.field_index = field->report_count - 1;
 557                 finfo.maxusage = field->maxusage;
 558                 finfo.flags = field->flags;
 559                 finfo.physical = field->physical;
 560                 finfo.logical = field->logical;
 561                 finfo.application = field->application;
 562                 finfo.logical_minimum = field->logical_minimum;
 563                 finfo.logical_maximum = field->logical_maximum;
 564                 finfo.physical_minimum = field->physical_minimum;
 565                 finfo.physical_maximum = field->physical_maximum;
 566                 finfo.unit_exponent = field->unit_exponent;
 567                 finfo.unit = field->unit;
 568
 569                 if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
 570                         return -EFAULT;
 571
 572                 return 0;
 573
 574         case HIDIOCGUCODE:
 575                 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
 576                 if (!uref_multi)
 577                         return -ENOMEM;
 578                 uref = &uref_multi->uref;
 579                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
 580                         goto fault;
 581
 582                 rinfo.report_type = uref->report_type;
 583                 rinfo.report_id = uref->report_id;
 584                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 585                         goto inval;
 586
 587                 if (uref->field_index >= report->maxfield)
 588                         goto inval;
 589
 590                 field = report->field[uref->field_index];
 591                 if (uref->usage_index >= field->maxusage)
 592                         goto inval;
 593
 594                 uref->usage_code = field->usage[uref->usage_index].hid;
 595
 596                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
 597                         goto fault;
 598
 599                 kfree(uref_multi);
 600                 return 0;
 601
 602         case HIDIOCGUSAGE:
 603         case HIDIOCSUSAGE:
 604         case HIDIOCGUSAGES:
 605         case HIDIOCSUSAGES:
 606         case HIDIOCGCOLLECTIONINDEX:
 607                 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
 608                 if (!uref_multi)
 609                         return -ENOMEM;
 610                 uref = &uref_multi->uref;
 611                 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
 612                         if (copy_from_user(uref_multi, user_arg,
 613                                            sizeof(*uref_multi)))
 614                                 goto fault;
 615                 } else {
 616                         if (copy_from_user(uref, user_arg, sizeof(*uref)))
 617                                 goto fault;
 618                 }
 619
 620                 if (cmd != HIDIOCGUSAGE &&
 621                     cmd != HIDIOCGUSAGES &&
 622                     uref->report_type == HID_REPORT_TYPE_INPUT)
 623                         goto inval;
 624
 625                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
 626                         field = hiddev_lookup_usage(hid, uref);
 627                         if (field == NULL)
 628                                 goto inval;
 629                 } else {
 630                         rinfo.report_type = uref->report_type;
 631                         rinfo.report_id = uref->report_id;
 632                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 633                                 goto inval;
 634
 635                         if (uref->field_index >= report->maxfield)
 636                                 goto inval;
 637
 638                         field = report->field[uref->field_index];
 639                         if (uref->usage_index >= field->maxusage)
 640                                 goto inval;
 641
 642                         if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
 643                                 if (uref_multi->num_values >= HID_MAX_USAGES ||
 644                                     uref->usage_index >= field->maxusage ||
 645                                    (uref->usage_index + uref_multi->num_values) >= field->maxusage)
 646                                         goto inval;
 647                         }
 648                 }
 649
 650                 switch (cmd) {
 651                         case HIDIOCGUSAGE:
 652                                 uref->value = field->value[uref->usage_index];
 653                                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
 654                                         goto fault;
 655                                 goto goodreturn;
 656
 657                         case HIDIOCSUSAGE:
 658                                 field->value[uref->usage_index] = uref->value;
 659                                 goto goodreturn;
 660
 661                         case HIDIOCGCOLLECTIONINDEX:
 662                                 kfree(uref_multi);
 663                                 return field->usage[uref->usage_index].collection_index;
 664                         case HIDIOCGUSAGES:
 665                                 for (i = 0; i < uref_multi->num_values; i++)
 666                                         uref_multi->values[i] =
 667                                             field->value[uref->usage_index + i];
 668                                 if (copy_to_user(user_arg, uref_multi,
 669                                                  sizeof(*uref_multi)))
 670                                         goto fault;
 671                                 goto goodreturn;
 672                         case HIDIOCSUSAGES:
 673                                 for (i = 0; i < uref_multi->num_values; i++)
 674                                         field->value[uref->usage_index + i] =
 675                                             uref_multi->values[i];
 676                                 goto goodreturn;
 677                 }
 678
 679 goodreturn:
 680                 kfree(uref_multi);
 681                 return 0;
 682 fault:
 683                 kfree(uref_multi);
 684                 return -EFAULT;
 685 inval:
 686                 kfree(uref_multi);
 687                 return -EINVAL;
 688
 689         case HIDIOCGCOLLECTIONINFO:
 690                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
 691                         return -EFAULT;
 692
 693                 if (cinfo.index >= hid->maxcollection)
 694                         return -EINVAL;
 695
 696                 cinfo.type = hid->collection[cinfo.index].type;
 697                 cinfo.usage = hid->collection[cinfo.index].usage;
 698                 cinfo.level = hid->collection[cinfo.index].level;
 699
 700                 if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
 701                         return -EFAULT;
 702                 return 0;
 703
 704         default:
 705
 706                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
 707                         return -EINVAL;
 708
 709                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
 710                         int len;
 711                         if (!hid->name)
 712                                 return 0;
 713                         len = strlen(hid->name) + 1;
 714                         if (len > _IOC_SIZE(cmd))
 715                                  len = _IOC_SIZE(cmd);
 716                         return copy_to_user(user_arg, hid->name, len) ?
 717                                 -EFAULT : len;
 718                 }
 719
 720                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
 721                         int len;
 722                         if (!hid->phys)
 723                                 return 0;
 724                         len = strlen(hid->phys) + 1;
 725                         if (len > _IOC_SIZE(cmd))
 726                                 len = _IOC_SIZE(cmd);
 727                         return copy_to_user(user_arg, hid->phys, len) ?
 728                                 -EFAULT : len;
 729                 }
 730         }
 731         return -EINVAL;
 732 }
 733
 734 static struct file_operations hiddev_fops = {
 735         .owner =        THIS_MODULE,
 736         .read =         hiddev_read,
 737         .write =        hiddev_write,
 738         .poll =         hiddev_poll,
 739         .open =         hiddev_open,
 740         .release =      hiddev_release,
 741         .ioctl =        hiddev_ioctl,
 742         .fasync =       hiddev_fasync,
 743 };
 744
 745 static struct usb_class_driver hiddev_class = {
 746         .name =         "usb/hid/hiddev%d",
 747         .fops =         &hiddev_fops,
 748         .mode =         S_IFCHR | S_IRUGO | S_IWUSR,
 749         .minor_base =   HIDDEV_MINOR_BASE,
 750 };
 751
 752 /*
 753  * This is where hid.c calls us to connect a hid device to the hiddev driver
 754  */
 755 int hiddev_connect(struct hid_device *hid)
 756 {
 757         struct hiddev *hiddev;
 758         int i;
 759         int retval;
 760
 761         for (i = 0; i < hid->maxcollection; i++)
 762                 if (hid->collection[i].type ==
 763                     HID_COLLECTION_APPLICATION &&
 764                     !IS_INPUT_APPLICATION(hid->collection[i].usage))
 765                         break;
 766
 767         if (i == hid->maxcollection && (hid->quirks & HID_QUIRK_HIDDEV) == 0)
 768                 return -1;
 769
 770         if (!(hiddev = kmalloc(sizeof(struct hiddev), GFP_KERNEL)))
 771                 return -1;
 772         memset(hiddev, 0, sizeof(struct hiddev));
 773
 774         retval = usb_register_dev(hid->intf, &hiddev_class);
 775         if (retval) {
 776                 err("Not able to get a minor for this device.");
 777                 kfree(hiddev);
 778                 return -1;
 779         }
 780
 781         init_waitqueue_head(&hiddev->wait);
 782
 783         hiddev_table[hid->intf->minor - HIDDEV_MINOR_BASE] = hiddev;
 784
 785         hiddev->hid = hid;
 786         hiddev->exist = 1;
 787
 788         hid->minor = hid->intf->minor;
 789         hid->hiddev = hiddev;
 790
 791         return 0;
 792 }
 793
 794 /*
 795  * This is where hid.c calls us to disconnect a hiddev device from the
 796  * corresponding hid device (usually because the usb device has disconnected)
 797  */
 798 void hiddev_disconnect(struct hid_device *hid)
 799 {
 800         struct hiddev *hiddev = hid->hiddev;
 801
 802         hiddev->exist = 0;
 803
 804         if (hiddev->open) {
 805                 hid_close(hiddev->hid);
 806                 wake_up_interruptible(&hiddev->wait);
 807         } else {
 808                 hiddev_cleanup(hiddev);
 809         }
 810 }
 811
 812 /* Currently this driver is a USB driver.  It's not a conventional one in
 813  * the sense that it doesn't probe at the USB level.  Instead it waits to
 814  * be connected by HID through the hiddev_connect / hiddev_disconnect
 815  * routines.  The reason to register as a USB device is to gain part of the
 816  * minor number space from the USB major.
 817  *
 818  * In theory, should the HID code be generalized to more than one physical
 819  * medium (say, IEEE 1384), this driver will probably need to register its
 820  * own major number, and in doing so, no longer need to register with USB.
 821  * At that point the probe routine and hiddev_driver struct below will no
 822  * longer be useful.
 823  */
 824
 825
 826 /* We never attach in this manner, and rely on HID to connect us.  This
 827  * is why there is no disconnect routine defined in the usb_driver either.
 828  */
 829 static int hiddev_usbd_probe(struct usb_interface *intf,
 830                              const struct usb_device_id *hiddev_info)
 831 {
 832         return -ENODEV;
 833 }
 834
 835
 836 static /* const */ struct usb_driver hiddev_driver = {
 837         .owner =        THIS_MODULE,
 838         .name =         "hiddev",
 839         .probe =        hiddev_usbd_probe,
 840 };
 841
 842 int __init hiddev_init(void)
 843 {
 844         devfs_mk_dir("usb/hid");
 845         return usb_register(&hiddev_driver);
 846 }
 847
 848 void hiddev_exit(void)
 849 {
 850         usb_deregister(&hiddev_driver);
 851         devfs_remove("usb/hid");
 852 }