drivers/hid/usbhid/hiddev.c

   1 /*
   2  *  Copyright (c) 2001 Paul Stewart
   3  *  Copyright (c) 2001 Vojtech Pavlik
   4  *
   5  *  HID char devices, giving access to raw HID device events.
   6  *
   7  */
   8
   9 /*
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  23  *
  24  * Should you need to contact me, the author, you can do so either by
  25  * e-mail - mail your message to Paul Stewart <stewart@wetlogic.net>
  26  */
  27
  28 #include <linux/poll.h>
  29 #include <linux/slab.h>
  30 #include <linux/module.h>
  31 #include <linux/init.h>
  32 #include <linux/smp_lock.h>
  33 #include <linux/input.h>
  34 #include <linux/usb.h>
  35 #include <linux/hid.h>
  36 #include <linux/hiddev.h>
  37 #include <linux/compat.h>
  38 #include "usbhid.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         struct mutex existancelock;
  53         wait_queue_head_t wait;
  54         struct hid_device *hid;
  55         struct list_head list;
  56         spinlock_t list_lock;
  57 };
  58
  59 struct hiddev_list {
  60         struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
  61         int head;
  62         int tail;
  63         unsigned flags;
  64         struct fasync_struct *fasync;
  65         struct hiddev *hiddev;
  66         struct list_head node;
  67         struct mutex thread_lock;
  68 };
  69
  70 static struct hiddev *hiddev_table[HIDDEV_MINORS];
  71
  72 /*
  73  * Find a report, given the report's type and ID.  The ID can be specified
  74  * indirectly by REPORT_ID_FIRST (which returns the first report of the given
  75  * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
  76  * given type which follows old_id.
  77  */
  78 static struct hid_report *
  79 hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
  80 {
  81         unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
  82         unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK;
  83         struct hid_report_enum *report_enum;
  84         struct hid_report *report;
  85         struct list_head *list;
  86
  87         if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
  88             rinfo->report_type > HID_REPORT_TYPE_MAX)
  89                 return NULL;
  90
  91         report_enum = hid->report_enum +
  92                 (rinfo->report_type - HID_REPORT_TYPE_MIN);
  93
  94         switch (flags) {
  95         case 0: /* Nothing to do -- report_id is already set correctly */
  96                 break;
  97
  98         case HID_REPORT_ID_FIRST:
  99                 if (list_empty(&report_enum->report_list))
 100                         return NULL;
 101
 102                 list = report_enum->report_list.next;
 103                 report = list_entry(list, struct hid_report, list);
 104                 rinfo->report_id = report->id;
 105                 break;
 106
 107         case HID_REPORT_ID_NEXT:
 108                 report = report_enum->report_id_hash[rid];
 109                 if (!report)
 110                         return NULL;
 111
 112                 list = report->list.next;
 113                 if (list == &report_enum->report_list)
 114                         return NULL;
 115
 116                 report = list_entry(list, struct hid_report, list);
 117                 rinfo->report_id = report->id;
 118                 break;
 119
 120         default:
 121                 return NULL;
 122         }
 123
 124         return report_enum->report_id_hash[rinfo->report_id];
 125 }
 126
 127 /*
 128  * Perform an exhaustive search of the report table for a usage, given its
 129  * type and usage id.
 130  */
 131 static struct hid_field *
 132 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
 133 {
 134         int i, j;
 135         struct hid_report *report;
 136         struct hid_report_enum *report_enum;
 137         struct hid_field *field;
 138
 139         if (uref->report_type < HID_REPORT_TYPE_MIN ||
 140             uref->report_type > HID_REPORT_TYPE_MAX)
 141                 return NULL;
 142
 143         report_enum = hid->report_enum +
 144                 (uref->report_type - HID_REPORT_TYPE_MIN);
 145
 146         list_for_each_entry(report, &report_enum->report_list, list) {
 147                 for (i = 0; i < report->maxfield; i++) {
 148                         field = report->field[i];
 149                         for (j = 0; j < field->maxusage; j++) {
 150                                 if (field->usage[j].hid == uref->usage_code) {
 151                                         uref->report_id = report->id;
 152                                         uref->field_index = i;
 153                                         uref->usage_index = j;
 154                                         return field;
 155                                 }
 156                         }
 157                 }
 158         }
 159
 160         return NULL;
 161 }
 162
 163 static void hiddev_send_event(struct hid_device *hid,
 164                               struct hiddev_usage_ref *uref)
 165 {
 166         struct hiddev *hiddev = hid->hiddev;
 167         struct hiddev_list *list;
 168         unsigned long flags;
 169
 170         spin_lock_irqsave(&hiddev->list_lock, flags);
 171         list_for_each_entry(list, &hiddev->list, node) {
 172                 if (uref->field_index != HID_FIELD_INDEX_NONE ||
 173                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 174                         list->buffer[list->head] = *uref;
 175                         list->head = (list->head + 1) &
 176                                 (HIDDEV_BUFFER_SIZE - 1);
 177                         kill_fasync(&list->fasync, SIGIO, POLL_IN);
 178                 }
 179         }
 180         spin_unlock_irqrestore(&hiddev->list_lock, flags);
 181
 182         wake_up_interruptible(&hiddev->wait);
 183 }
 184
 185 /*
 186  * This is where hid.c calls into hiddev to pass an event that occurred over
 187  * the interrupt pipe
 188  */
 189 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
 190                       struct hid_usage *usage, __s32 value)
 191 {
 192         unsigned type = field->report_type;
 193         struct hiddev_usage_ref uref;
 194
 195         uref.report_type =
 196           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
 197           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
 198            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
 199         uref.report_id = field->report->id;
 200         uref.field_index = field->index;
 201         uref.usage_index = (usage - field->usage);
 202         uref.usage_code = usage->hid;
 203         uref.value = value;
 204
 205         hiddev_send_event(hid, &uref);
 206 }
 207 EXPORT_SYMBOL_GPL(hiddev_hid_event);
 208
 209 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
 210 {
 211         unsigned type = report->type;
 212         struct hiddev_usage_ref uref;
 213
 214         memset(&uref, 0, sizeof(uref));
 215         uref.report_type =
 216           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
 217           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
 218            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
 219         uref.report_id = report->id;
 220         uref.field_index = HID_FIELD_INDEX_NONE;
 221
 222         hiddev_send_event(hid, &uref);
 223 }
 224
 225 /*
 226  * fasync file op
 227  */
 228 static int hiddev_fasync(int fd, struct file *file, int on)
 229 {
 230         int retval;
 231         struct hiddev_list *list = file->private_data;
 232
 233         retval = fasync_helper(fd, file, on, &list->fasync);
 234
 235         return retval < 0 ? retval : 0;
 236 }
 237
 238
 239 /*
 240  * release file op
 241  */
 242 static int hiddev_release(struct inode * inode, struct file * file)
 243 {
 244         struct hiddev_list *list = file->private_data;
 245         unsigned long flags;
 246
 247         spin_lock_irqsave(&list->hiddev->list_lock, flags);
 248         list_del(&list->node);
 249         spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
 250
 251         if (!--list->hiddev->open) {
 252                 if (list->hiddev->exist) {
 253                         usbhid_close(list->hiddev->hid);
 254                         usbhid_put_power(list->hiddev->hid);
 255                 } else {
 256                         kfree(list->hiddev);
 257                 }
 258         }
 259
 260         kfree(list);
 261
 262         return 0;
 263 }
 264
 265 /*
 266  * open file op
 267  */
 268 static int hiddev_open(struct inode *inode, struct file *file)
 269 {
 270         struct hiddev_list *list;
 271         int res;
 272
 273         int i = iminor(inode) - HIDDEV_MINOR_BASE;
 274
 275         if (i >= HIDDEV_MINORS || i < 0 || !hiddev_table[i])
 276                 return -ENODEV;
 277
 278         if (!(list = kzalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
 279                 return -ENOMEM;
 280         mutex_init(&list->thread_lock);
 281
 282         list->hiddev = hiddev_table[i];
 283
 284
 285         file->private_data = list;
 286
 287         /*
 288          * no need for locking because the USB major number
 289          * is shared which usbcore guards against disconnect
 290          */
 291         if (list->hiddev->exist) {
 292                 if (!list->hiddev->open++) {
 293                         res = usbhid_open(hiddev_table[i]->hid);
 294                         if (res < 0) {
 295                                 res = -EIO;
 296                                 goto bail;
 297                         }
 298                 }
 299         } else {
 300                 res = -ENODEV;
 301                 goto bail;
 302         }
 303
 304         spin_lock_irq(&list->hiddev->list_lock);
 305         list_add_tail(&list->node, &hiddev_table[i]->list);
 306         spin_unlock_irq(&list->hiddev->list_lock);
 307
 308         if (!list->hiddev->open++)
 309                 if (list->hiddev->exist) {
 310                         struct hid_device *hid = hiddev_table[i]->hid;
 311                         res = usbhid_get_power(hid);
 312                         if (res < 0) {
 313                                 res = -EIO;
 314                                 goto bail;
 315                         }
 316                         usbhid_open(hid);
 317                 }
 318
 319         return 0;
 320 bail:
 321         file->private_data = NULL;
 322         kfree(list);
 323         return res;
 324 }
 325
 326 /*
 327  * "write" file op
 328  */
 329 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
 330 {
 331         return -EINVAL;
 332 }
 333
 334 /*
 335  * "read" file op
 336  */
 337 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
 338 {
 339         DEFINE_WAIT(wait);
 340         struct hiddev_list *list = file->private_data;
 341         int event_size;
 342         int retval;
 343
 344         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
 345                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
 346
 347         if (count < event_size)
 348                 return 0;
 349
 350         /* lock against other threads */
 351         retval = mutex_lock_interruptible(&list->thread_lock);
 352         if (retval)
 353                 return -ERESTARTSYS;
 354
 355         while (retval == 0) {
 356                 if (list->head == list->tail) {
 357                         prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);
 358
 359                         while (list->head == list->tail) {
 360                                 if (file->f_flags & O_NONBLOCK) {
 361                                         retval = -EAGAIN;
 362                                         break;
 363                                 }
 364                                 if (signal_pending(current)) {
 365                                         retval = -ERESTARTSYS;
 366                                         break;
 367                                 }
 368                                 if (!list->hiddev->exist) {
 369                                         retval = -EIO;
 370                                         break;
 371                                 }
 372
 373                                 /* let O_NONBLOCK tasks run */
 374                                 mutex_unlock(&list->thread_lock);
 375                                 schedule();
 376                                 if (mutex_lock_interruptible(&list->thread_lock))
 377                                         return -EINTR;
 378                                 set_current_state(TASK_INTERRUPTIBLE);
 379                         }
 380                         finish_wait(&list->hiddev->wait, &wait);
 381
 382                 }
 383
 384                 if (retval) {
 385                         mutex_unlock(&list->thread_lock);
 386                         return retval;
 387                 }
 388
 389
 390                 while (list->head != list->tail &&
 391                        retval + event_size <= count) {
 392                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
 393                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
 394                                         struct hiddev_event event;
 395
 396                                         event.hid = list->buffer[list->tail].usage_code;
 397                                         event.value = list->buffer[list->tail].value;
 398                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {
 399                                                 mutex_unlock(&list->thread_lock);
 400                                                 return -EFAULT;
 401                                         }
 402                                         retval += sizeof(struct hiddev_event);
 403                                 }
 404                         } else {
 405                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
 406                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 407
 408                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {
 409                                                 mutex_unlock(&list->thread_lock);
 410                                                 return -EFAULT;
 411                                         }
 412                                         retval += sizeof(struct hiddev_usage_ref);
 413                                 }
 414                         }
 415                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
 416                 }
 417
 418         }
 419         mutex_unlock(&list->thread_lock);
 420
 421         return retval;
 422 }
 423
 424 /*
 425  * "poll" file op
 426  * No kernel lock - fine
 427  */
 428 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
 429 {
 430         struct hiddev_list *list = file->private_data;
 431
 432         poll_wait(file, &list->hiddev->wait, wait);
 433         if (list->head != list->tail)
 434                 return POLLIN | POLLRDNORM;
 435         if (!list->hiddev->exist)
 436                 return POLLERR | POLLHUP;
 437         return 0;
 438 }
 439
 440 /*
 441  * "ioctl" file op
 442  */
 443 static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 444 {
 445         struct hid_device *hid = hiddev->hid;
 446         struct hiddev_report_info rinfo;
 447         struct hiddev_usage_ref_multi *uref_multi = NULL;
 448         struct hiddev_usage_ref *uref;
 449         struct hid_report *report;
 450         struct hid_field *field;
 451         int i;
 452
 453         uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
 454         if (!uref_multi)
 455                 return -ENOMEM;
 456         lock_kernel();
 457         uref = &uref_multi->uref;
 458         if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
 459                 if (copy_from_user(uref_multi, user_arg,
 460                                    sizeof(*uref_multi)))
 461                         goto fault;
 462         } else {
 463                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
 464                         goto fault;
 465         }
 466
 467         switch (cmd) {
 468         case HIDIOCGUCODE:
 469                 rinfo.report_type = uref->report_type;
 470                 rinfo.report_id = uref->report_id;
 471                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 472                         goto inval;
 473
 474                 if (uref->field_index >= report->maxfield)
 475                         goto inval;
 476
 477                 field = report->field[uref->field_index];
 478                 if (uref->usage_index >= field->maxusage)
 479                         goto inval;
 480
 481                 uref->usage_code = field->usage[uref->usage_index].hid;
 482
 483                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
 484                         goto fault;
 485
 486                 goto goodreturn;
 487
 488         default:
 489                 if (cmd != HIDIOCGUSAGE &&
 490                     cmd != HIDIOCGUSAGES &&
 491                     uref->report_type == HID_REPORT_TYPE_INPUT)
 492                         goto inval;
 493
 494                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
 495                         field = hiddev_lookup_usage(hid, uref);
 496                         if (field == NULL)
 497                                 goto inval;
 498                 } else {
 499                         rinfo.report_type = uref->report_type;
 500                         rinfo.report_id = uref->report_id;
 501                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 502                                 goto inval;
 503
 504                         if (uref->field_index >= report->maxfield)
 505                                 goto inval;
 506
 507                         field = report->field[uref->field_index];
 508
 509                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
 510                                 if (uref->usage_index >= field->maxusage)
 511                                         goto inval;
 512                         } else if (uref->usage_index >= field->report_count)
 513                                 goto inval;
 514
 515                         else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
 516                                  (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
 517                                   uref->usage_index + uref_multi->num_values > field->report_count))
 518                                 goto inval;
 519                         }
 520
 521                 switch (cmd) {
 522                 case HIDIOCGUSAGE:
 523                         uref->value = field->value[uref->usage_index];
 524                         if (copy_to_user(user_arg, uref, sizeof(*uref)))
 525                                 goto fault;
 526                         goto goodreturn;
 527
 528                 case HIDIOCSUSAGE:
 529                         field->value[uref->usage_index] = uref->value;
 530                         goto goodreturn;
 531
 532                 case HIDIOCGCOLLECTIONINDEX:
 533                         kfree(uref_multi);
 534                         return field->usage[uref->usage_index].collection_index;
 535                 case HIDIOCGUSAGES:
 536                         for (i = 0; i < uref_multi->num_values; i++)
 537                                 uref_multi->values[i] =
 538                                     field->value[uref->usage_index + i];
 539                         if (copy_to_user(user_arg, uref_multi,
 540                                          sizeof(*uref_multi)))
 541                                 goto fault;
 542                         goto goodreturn;
 543                 case HIDIOCSUSAGES:
 544                         for (i = 0; i < uref_multi->num_values; i++)
 545                                 field->value[uref->usage_index + i] =
 546                                     uref_multi->values[i];
 547                         goto goodreturn;
 548                 }
 549
 550 goodreturn:
 551                 unlock_kernel();
 552                 kfree(uref_multi);
 553                 return 0;
 554 fault:
 555                 unlock_kernel();
 556                 kfree(uref_multi);
 557                 return -EFAULT;
 558 inval:
 559                 unlock_kernel();
 560                 kfree(uref_multi);
 561                 return -EINVAL;
 562         }
 563 }
 564
 565 static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 566 {
 567         struct hid_device *hid = hiddev->hid;
 568         struct usb_device *dev = hid_to_usb_dev(hid);
 569         int idx, len;
 570         char *buf;
 571
 572         if (get_user(idx, (int __user *)user_arg))
 573                 return -EFAULT;
 574
 575         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
 576                 return -ENOMEM;
 577
 578         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
 579                 kfree(buf);
 580                 return -EINVAL;
 581         }
 582
 583         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
 584                 kfree(buf);
 585                 return -EFAULT;
 586         }
 587
 588         kfree(buf);
 589
 590         return len;
 591 }
 592
 593 static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 594 {
 595         struct hiddev_list *list = file->private_data;
 596         struct hiddev *hiddev = list->hiddev;
 597         struct hid_device *hid = hiddev->hid;
 598         struct usb_device *dev = hid_to_usb_dev(hid);
 599         struct hiddev_collection_info cinfo;
 600         struct hiddev_report_info rinfo;
 601         struct hiddev_field_info finfo;
 602         struct hiddev_devinfo dinfo;
 603         struct hid_report *report;
 604         struct hid_field *field;
 605         struct usbhid_device *usbhid = hid->driver_data;
 606         void __user *user_arg = (void __user *)arg;
 607         int i, r;
 608
 609         /* Called without BKL by compat methods so no BKL taken */
 610
 611         /* FIXME: Who or what stop this racing with a disconnect ?? */
 612         if (!hiddev->exist)
 613                 return -EIO;
 614
 615         switch (cmd) {
 616
 617         case HIDIOCGVERSION:
 618                 return put_user(HID_VERSION, (int __user *)arg);
 619
 620         case HIDIOCAPPLICATION:
 621                 if (arg < 0 || arg >= hid->maxapplication)
 622                         return -EINVAL;
 623
 624                 for (i = 0; i < hid->maxcollection; i++)
 625                         if (hid->collection[i].type ==
 626                             HID_COLLECTION_APPLICATION && arg-- == 0)
 627                                 break;
 628
 629                 if (i == hid->maxcollection)
 630                         return -EINVAL;
 631
 632                 return hid->collection[i].usage;
 633
 634         case HIDIOCGDEVINFO:
 635                 dinfo.bustype = BUS_USB;
 636                 dinfo.busnum = dev->bus->busnum;
 637                 dinfo.devnum = dev->devnum;
 638                 dinfo.ifnum = usbhid->ifnum;
 639                 dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
 640                 dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
 641                 dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
 642                 dinfo.num_applications = hid->maxapplication;
 643                 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
 644                         return -EFAULT;
 645
 646                 return 0;
 647
 648         case HIDIOCGFLAG:
 649                 if (put_user(list->flags, (int __user *)arg))
 650                         return -EFAULT;
 651
 652                 return 0;
 653
 654         case HIDIOCSFLAG:
 655                 {
 656                         int newflags;
 657                         if (get_user(newflags, (int __user *)arg))
 658                                 return -EFAULT;
 659
 660                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
 661                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
 662                              (newflags & HIDDEV_FLAG_UREF) == 0))
 663                                 return -EINVAL;
 664
 665                         list->flags = newflags;
 666
 667                         return 0;
 668                 }
 669
 670         case HIDIOCGSTRING:
 671                 mutex_lock(&hiddev->existancelock);
 672                 if (hiddev->exist)
 673                         r = hiddev_ioctl_string(hiddev, cmd, user_arg);
 674                 else
 675                         r = -ENODEV;
 676                 mutex_unlock(&hiddev->existancelock);
 677                 return r;
 678
 679         case HIDIOCINITREPORT:
 680                 mutex_lock(&hiddev->existancelock);
 681                 if (!hiddev->exist) {
 682                         mutex_unlock(&hiddev->existancelock);
 683                         return -ENODEV;
 684                 }
 685                 usbhid_init_reports(hid);
 686                 mutex_unlock(&hiddev->existancelock);
 687
 688                 return 0;
 689
 690         case HIDIOCGREPORT:
 691                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
 692                         return -EFAULT;
 693
 694                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
 695                         return -EINVAL;
 696
 697                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 698                         return -EINVAL;
 699
 700                 mutex_lock(&hiddev->existancelock);
 701                 if (hiddev->exist) {
 702                         usbhid_submit_report(hid, report, USB_DIR_IN);
 703                         usbhid_wait_io(hid);
 704                 }
 705                 mutex_unlock(&hiddev->existancelock);
 706
 707                 return 0;
 708
 709         case HIDIOCSREPORT:
 710                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
 711                         return -EFAULT;
 712
 713                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
 714                         return -EINVAL;
 715
 716                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 717                         return -EINVAL;
 718
 719                 mutex_lock(&hiddev->existancelock);
 720                 if (hiddev->exist) {
 721                         usbhid_submit_report(hid, report, USB_DIR_OUT);
 722                         usbhid_wait_io(hid);
 723                 }
 724                 mutex_unlock(&hiddev->existancelock);
 725
 726                 return 0;
 727
 728         case HIDIOCGREPORTINFO:
 729                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
 730                         return -EFAULT;
 731
 732                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 733                         return -EINVAL;
 734
 735                 rinfo.num_fields = report->maxfield;
 736
 737                 if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
 738                         return -EFAULT;
 739
 740                 return 0;
 741
 742         case HIDIOCGFIELDINFO:
 743                 if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
 744                         return -EFAULT;
 745                 rinfo.report_type = finfo.report_type;
 746                 rinfo.report_id = finfo.report_id;
 747                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 748                         return -EINVAL;
 749
 750                 if (finfo.field_index >= report->maxfield)
 751                         return -EINVAL;
 752
 753                 field = report->field[finfo.field_index];
 754                 memset(&finfo, 0, sizeof(finfo));
 755                 finfo.report_type = rinfo.report_type;
 756                 finfo.report_id = rinfo.report_id;
 757                 finfo.field_index = field->report_count - 1;
 758                 finfo.maxusage = field->maxusage;
 759                 finfo.flags = field->flags;
 760                 finfo.physical = field->physical;
 761                 finfo.logical = field->logical;
 762                 finfo.application = field->application;
 763                 finfo.logical_minimum = field->logical_minimum;
 764                 finfo.logical_maximum = field->logical_maximum;
 765                 finfo.physical_minimum = field->physical_minimum;
 766                 finfo.physical_maximum = field->physical_maximum;
 767                 finfo.unit_exponent = field->unit_exponent;
 768                 finfo.unit = field->unit;
 769
 770                 if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
 771                         return -EFAULT;
 772
 773                 return 0;
 774
 775         case HIDIOCGUCODE:
 776                 /* fall through */
 777         case HIDIOCGUSAGE:
 778         case HIDIOCSUSAGE:
 779         case HIDIOCGUSAGES:
 780         case HIDIOCSUSAGES:
 781         case HIDIOCGCOLLECTIONINDEX:
 782                 mutex_lock(&hiddev->existancelock);
 783                 if (hiddev->exist)
 784                         r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
 785                 else
 786                         r = -ENODEV;
 787                 mutex_unlock(&hiddev->existancelock);
 788                 return r;
 789
 790         case HIDIOCGCOLLECTIONINFO:
 791                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
 792                         return -EFAULT;
 793
 794                 if (cinfo.index >= hid->maxcollection)
 795                         return -EINVAL;
 796
 797                 cinfo.type = hid->collection[cinfo.index].type;
 798                 cinfo.usage = hid->collection[cinfo.index].usage;
 799                 cinfo.level = hid->collection[cinfo.index].level;
 800
 801                 if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
 802                         return -EFAULT;
 803                 return 0;
 804
 805         default:
 806
 807                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
 808                         return -EINVAL;
 809
 810                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
 811                         int len;
 812                         if (!hid->name)
 813                                 return 0;
 814                         len = strlen(hid->name) + 1;
 815                         if (len > _IOC_SIZE(cmd))
 816                                  len = _IOC_SIZE(cmd);
 817                         return copy_to_user(user_arg, hid->name, len) ?
 818                                 -EFAULT : len;
 819                 }
 820
 821                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
 822                         int len;
 823                         if (!hid->phys)
 824                                 return 0;
 825                         len = strlen(hid->phys) + 1;
 826                         if (len > _IOC_SIZE(cmd))
 827                                 len = _IOC_SIZE(cmd);
 828                         return copy_to_user(user_arg, hid->phys, len) ?
 829                                 -EFAULT : len;
 830                 }
 831         }
 832         return -EINVAL;
 833 }
 834
 835 #ifdef CONFIG_COMPAT
 836 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 837 {
 838         return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
 839 }
 840 #endif
 841
 842 static const struct file_operations hiddev_fops = {
 843         .owner =        THIS_MODULE,
 844         .read =         hiddev_read,
 845         .write =        hiddev_write,
 846         .poll =         hiddev_poll,
 847         .open =         hiddev_open,
 848         .release =      hiddev_release,
 849         .unlocked_ioctl =       hiddev_ioctl,
 850         .fasync =       hiddev_fasync,
 851 #ifdef CONFIG_COMPAT
 852         .compat_ioctl   = hiddev_compat_ioctl,
 853 #endif
 854 };
 855
 856 static struct usb_class_driver hiddev_class = {
 857         .name =         "hiddev%d",
 858         .fops =         &hiddev_fops,
 859         .minor_base =   HIDDEV_MINOR_BASE,
 860 };
 861
 862 /*
 863  * This is where hid.c calls us to connect a hid device to the hiddev driver
 864  */
 865 int hiddev_connect(struct hid_device *hid, unsigned int force)
 866 {
 867         struct hiddev *hiddev;
 868         struct usbhid_device *usbhid = hid->driver_data;
 869         int retval;
 870
 871         if (!force) {
 872                 unsigned int i;
 873                 for (i = 0; i < hid->maxcollection; i++)
 874                         if (hid->collection[i].type ==
 875                             HID_COLLECTION_APPLICATION &&
 876                             !IS_INPUT_APPLICATION(hid->collection[i].usage))
 877                                 break;
 878
 879                 if (i == hid->maxcollection)
 880                         return -1;
 881         }
 882
 883         if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
 884                 return -1;
 885
 886         init_waitqueue_head(&hiddev->wait);
 887         INIT_LIST_HEAD(&hiddev->list);
 888         spin_lock_init(&hiddev->list_lock);
 889         mutex_init(&hiddev->existancelock);
 890         hid->hiddev = hiddev;
 891         hiddev->hid = hid;
 892         hiddev->exist = 1;
 893
 894         retval = usb_register_dev(usbhid->intf, &hiddev_class);
 895         if (retval) {
 896                 err_hid("Not able to get a minor for this device.");
 897                 hid->hiddev = NULL;
 898                 kfree(hiddev);
 899                 return -1;
 900         } else {
 901                 hid->minor = usbhid->intf->minor;
 902                 hiddev_table[usbhid->intf->minor - HIDDEV_MINOR_BASE] = hiddev;
 903         }
 904
 905         return 0;
 906 }
 907
 908 /*
 909  * This is where hid.c calls us to disconnect a hiddev device from the
 910  * corresponding hid device (usually because the usb device has disconnected)
 911  */
 912 static struct usb_class_driver hiddev_class;
 913 void hiddev_disconnect(struct hid_device *hid)
 914 {
 915         struct hiddev *hiddev = hid->hiddev;
 916         struct usbhid_device *usbhid = hid->driver_data;
 917
 918         mutex_lock(&hiddev->existancelock);
 919         hiddev->exist = 0;
 920         mutex_unlock(&hiddev->existancelock);
 921
 922         hiddev_table[hiddev->hid->minor - HIDDEV_MINOR_BASE] = NULL;
 923         usb_deregister_dev(usbhid->intf, &hiddev_class);
 924
 925         if (hiddev->open) {
 926                 usbhid_close(hiddev->hid);
 927                 wake_up_interruptible(&hiddev->wait);
 928         } else {
 929                 kfree(hiddev);
 930         }
 931 }
 932
 933 /* Currently this driver is a USB driver.  It's not a conventional one in
 934  * the sense that it doesn't probe at the USB level.  Instead it waits to
 935  * be connected by HID through the hiddev_connect / hiddev_disconnect
 936  * routines.  The reason to register as a USB device is to gain part of the
 937  * minor number space from the USB major.
 938  *
 939  * In theory, should the HID code be generalized to more than one physical
 940  * medium (say, IEEE 1384), this driver will probably need to register its
 941  * own major number, and in doing so, no longer need to register with USB.
 942  * At that point the probe routine and hiddev_driver struct below will no
 943  * longer be useful.
 944  */
 945
 946
 947 /* We never attach in this manner, and rely on HID to connect us.  This
 948  * is why there is no disconnect routine defined in the usb_driver either.
 949  */
 950 static int hiddev_usbd_probe(struct usb_interface *intf,
 951                              const struct usb_device_id *hiddev_info)
 952 {
 953         return -ENODEV;
 954 }
 955
 956
 957 static /* const */ struct usb_driver hiddev_driver = {
 958         .name =         "hiddev",
 959         .probe =        hiddev_usbd_probe,
 960 };
 961
 962 int __init hiddev_init(void)
 963 {
 964         return usb_register(&hiddev_driver);
 965 }
 966
 967 void hiddev_exit(void)
 968 {
 969         usb_deregister(&hiddev_driver);
 970 }