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                 else
 255                         kfree(list->hiddev);
 256         }
 257
 258         kfree(list);
 259
 260         return 0;
 261 }
 262
 263 /*
 264  * open file op
 265  */
 266 static int hiddev_open(struct inode *inode, struct file *file)
 267 {
 268         struct hiddev_list *list;
 269         int res;
 270
 271         int i = iminor(inode) - HIDDEV_MINOR_BASE;
 272
 273         if (i >= HIDDEV_MINORS || i < 0 || !hiddev_table[i])
 274                 return -ENODEV;
 275
 276         if (!(list = kzalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
 277                 return -ENOMEM;
 278         mutex_init(&list->thread_lock);
 279
 280         list->hiddev = hiddev_table[i];
 281
 282
 283         file->private_data = list;
 284
 285         /*
 286          * no need for locking because the USB major number
 287          * is shared which usbcore guards against disconnect
 288          */
 289         if (list->hiddev->exist) {
 290                 if (!list->hiddev->open++) {
 291                         res = usbhid_open(hiddev_table[i]->hid);
 292                         if (res < 0) {
 293                                 res = -EIO;
 294                                 goto bail;
 295                         }
 296                 }
 297         } else {
 298                 res = -ENODEV;
 299                 goto bail;
 300         }
 301
 302         spin_lock_irq(&list->hiddev->list_lock);
 303         list_add_tail(&list->node, &hiddev_table[i]->list);
 304         spin_unlock_irq(&list->hiddev->list_lock);
 305
 306         return 0;
 307 bail:
 308         file->private_data = NULL;
 309         kfree(list->hiddev);
 310         return res;
 311 }
 312
 313 /*
 314  * "write" file op
 315  */
 316 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
 317 {
 318         return -EINVAL;
 319 }
 320
 321 /*
 322  * "read" file op
 323  */
 324 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
 325 {
 326         DECLARE_WAITQUEUE(wait, current);
 327         struct hiddev_list *list = file->private_data;
 328         int event_size;
 329         int retval;
 330
 331         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
 332                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
 333
 334         if (count < event_size)
 335                 return 0;
 336
 337         /* lock against other threads */
 338         retval = mutex_lock_interruptible(&list->thread_lock);
 339         if (retval)
 340                 return -ERESTARTSYS;
 341
 342         while (retval == 0) {
 343                 if (list->head == list->tail) {
 344                         prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);
 345
 346                         while (list->head == list->tail) {
 347                                 if (file->f_flags & O_NONBLOCK) {
 348                                         retval = -EAGAIN;
 349                                         break;
 350                                 }
 351                                 if (signal_pending(current)) {
 352                                         retval = -ERESTARTSYS;
 353                                         break;
 354                                 }
 355                                 if (!list->hiddev->exist) {
 356                                         retval = -EIO;
 357                                         break;
 358                                 }
 359
 360                                 /* let O_NONBLOCK tasks run */
 361                                 mutex_unlock(&list->thread_lock);
 362                                 schedule();
 363                                 if (mutex_lock_interruptible(&list->thread_lock))
 364                                         return -EINTR;
 365                                 set_current_state(TASK_INTERRUPTIBLE);
 366                         }
 367                         finish_wait(&list->hiddev->wait, &wait);
 368
 369                 }
 370
 371                 if (retval) {
 372                         mutex_unlock(&list->thread_lock);
 373                         return retval;
 374                 }
 375
 376
 377                 while (list->head != list->tail &&
 378                        retval + event_size <= count) {
 379                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
 380                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
 381                                         struct hiddev_event event;
 382
 383                                         event.hid = list->buffer[list->tail].usage_code;
 384                                         event.value = list->buffer[list->tail].value;
 385                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {
 386                                                 mutex_unlock(&list->thread_lock);
 387                                                 return -EFAULT;
 388                                         }
 389                                         retval += sizeof(struct hiddev_event);
 390                                 }
 391                         } else {
 392                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
 393                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 394
 395                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {
 396                                                 mutex_unlock(&list->thread_lock);
 397                                                 return -EFAULT;
 398                                         }
 399                                         retval += sizeof(struct hiddev_usage_ref);
 400                                 }
 401                         }
 402                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
 403                 }
 404
 405         }
 406         mutex_unlock(&list->thread_lock);
 407
 408         return retval;
 409 }
 410
 411 /*
 412  * "poll" file op
 413  * No kernel lock - fine
 414  */
 415 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
 416 {
 417         struct hiddev_list *list = file->private_data;
 418
 419         poll_wait(file, &list->hiddev->wait, wait);
 420         if (list->head != list->tail)
 421                 return POLLIN | POLLRDNORM;
 422         if (!list->hiddev->exist)
 423                 return POLLERR | POLLHUP;
 424         return 0;
 425 }
 426
 427 /*
 428  * "ioctl" file op
 429  */
 430 static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 431 {
 432         struct hid_device *hid = hiddev->hid;
 433         struct hiddev_report_info rinfo;
 434         struct hiddev_usage_ref_multi *uref_multi = NULL;
 435         struct hiddev_usage_ref *uref;
 436         struct hid_report *report;
 437         struct hid_field *field;
 438         int i;
 439
 440         uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
 441         if (!uref_multi)
 442                 return -ENOMEM;
 443         lock_kernel();
 444         uref = &uref_multi->uref;
 445         if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
 446                 if (copy_from_user(uref_multi, user_arg,
 447                                    sizeof(*uref_multi)))
 448                         goto fault;
 449         } else {
 450                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
 451                         goto fault;
 452         }
 453
 454         switch (cmd) {
 455         case HIDIOCGUCODE:
 456                 rinfo.report_type = uref->report_type;
 457                 rinfo.report_id = uref->report_id;
 458                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 459                         goto inval;
 460
 461                 if (uref->field_index >= report->maxfield)
 462                         goto inval;
 463
 464                 field = report->field[uref->field_index];
 465                 if (uref->usage_index >= field->maxusage)
 466                         goto inval;
 467
 468                 uref->usage_code = field->usage[uref->usage_index].hid;
 469
 470                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
 471                         goto fault;
 472
 473                 goto goodreturn;
 474
 475         default:
 476                 if (cmd != HIDIOCGUSAGE &&
 477                     cmd != HIDIOCGUSAGES &&
 478                     uref->report_type == HID_REPORT_TYPE_INPUT)
 479                         goto inval;
 480
 481                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
 482                         field = hiddev_lookup_usage(hid, uref);
 483                         if (field == NULL)
 484                                 goto inval;
 485                 } else {
 486                         rinfo.report_type = uref->report_type;
 487                         rinfo.report_id = uref->report_id;
 488                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 489                                 goto inval;
 490
 491                         if (uref->field_index >= report->maxfield)
 492                                 goto inval;
 493
 494                         field = report->field[uref->field_index];
 495
 496                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
 497                                 if (uref->usage_index >= field->maxusage)
 498                                         goto inval;
 499                         } else if (uref->usage_index >= field->report_count)
 500                                 goto inval;
 501
 502                         else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
 503                                  (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
 504                                   uref->usage_index + uref_multi->num_values > field->report_count))
 505                                 goto inval;
 506                         }
 507
 508                 switch (cmd) {
 509                 case HIDIOCGUSAGE:
 510                         uref->value = field->value[uref->usage_index];
 511                         if (copy_to_user(user_arg, uref, sizeof(*uref)))
 512                                 goto fault;
 513                         goto goodreturn;
 514
 515                 case HIDIOCSUSAGE:
 516                         field->value[uref->usage_index] = uref->value;
 517                         goto goodreturn;
 518
 519                 case HIDIOCGCOLLECTIONINDEX:
 520                         kfree(uref_multi);
 521                         return field->usage[uref->usage_index].collection_index;
 522                 case HIDIOCGUSAGES:
 523                         for (i = 0; i < uref_multi->num_values; i++)
 524                                 uref_multi->values[i] =
 525                                     field->value[uref->usage_index + i];
 526                         if (copy_to_user(user_arg, uref_multi,
 527                                          sizeof(*uref_multi)))
 528                                 goto fault;
 529                         goto goodreturn;
 530                 case HIDIOCSUSAGES:
 531                         for (i = 0; i < uref_multi->num_values; i++)
 532                                 field->value[uref->usage_index + i] =
 533                                     uref_multi->values[i];
 534                         goto goodreturn;
 535                 }
 536
 537 goodreturn:
 538                 unlock_kernel();
 539                 kfree(uref_multi);
 540                 return 0;
 541 fault:
 542                 unlock_kernel();
 543                 kfree(uref_multi);
 544                 return -EFAULT;
 545 inval:
 546                 unlock_kernel();
 547                 kfree(uref_multi);
 548                 return -EINVAL;
 549         }
 550 }
 551
 552 static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 553 {
 554         struct hid_device *hid = hiddev->hid;
 555         struct usb_device *dev = hid_to_usb_dev(hid);
 556         int idx, len;
 557         char *buf;
 558
 559         if (get_user(idx, (int __user *)user_arg))
 560                 return -EFAULT;
 561
 562         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
 563                 return -ENOMEM;
 564
 565         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
 566                 kfree(buf);
 567                 return -EINVAL;
 568         }
 569
 570         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
 571                 kfree(buf);
 572                 return -EFAULT;
 573         }
 574
 575         kfree(buf);
 576
 577         return len;
 578 }
 579
 580 static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 581 {
 582         struct hiddev_list *list = file->private_data;
 583         struct hiddev *hiddev = list->hiddev;
 584         struct hid_device *hid = hiddev->hid;
 585         struct usb_device *dev = hid_to_usb_dev(hid);
 586         struct hiddev_collection_info cinfo;
 587         struct hiddev_report_info rinfo;
 588         struct hiddev_field_info finfo;
 589         struct hiddev_devinfo dinfo;
 590         struct hid_report *report;
 591         struct hid_field *field;
 592         struct usbhid_device *usbhid = hid->driver_data;
 593         void __user *user_arg = (void __user *)arg;
 594         int i, r;
 595
 596         /* Called without BKL by compat methods so no BKL taken */
 597
 598         /* FIXME: Who or what stop this racing with a disconnect ?? */
 599         if (!hiddev->exist)
 600                 return -EIO;
 601
 602         switch (cmd) {
 603
 604         case HIDIOCGVERSION:
 605                 return put_user(HID_VERSION, (int __user *)arg);
 606
 607         case HIDIOCAPPLICATION:
 608                 if (arg < 0 || arg >= hid->maxapplication)
 609                         return -EINVAL;
 610
 611                 for (i = 0; i < hid->maxcollection; i++)
 612                         if (hid->collection[i].type ==
 613                             HID_COLLECTION_APPLICATION && arg-- == 0)
 614                                 break;
 615
 616                 if (i == hid->maxcollection)
 617                         return -EINVAL;
 618
 619                 return hid->collection[i].usage;
 620
 621         case HIDIOCGDEVINFO:
 622                 dinfo.bustype = BUS_USB;
 623                 dinfo.busnum = dev->bus->busnum;
 624                 dinfo.devnum = dev->devnum;
 625                 dinfo.ifnum = usbhid->ifnum;
 626                 dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
 627                 dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
 628                 dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
 629                 dinfo.num_applications = hid->maxapplication;
 630                 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
 631                         return -EFAULT;
 632
 633                 return 0;
 634
 635         case HIDIOCGFLAG:
 636                 if (put_user(list->flags, (int __user *)arg))
 637                         return -EFAULT;
 638
 639                 return 0;
 640
 641         case HIDIOCSFLAG:
 642                 {
 643                         int newflags;
 644                         if (get_user(newflags, (int __user *)arg))
 645                                 return -EFAULT;
 646
 647                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
 648                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
 649                              (newflags & HIDDEV_FLAG_UREF) == 0))
 650                                 return -EINVAL;
 651
 652                         list->flags = newflags;
 653
 654                         return 0;
 655                 }
 656
 657         case HIDIOCGSTRING:
 658                 mutex_lock(&hiddev->existancelock);
 659                 if (hiddev->exist)
 660                         r = hiddev_ioctl_string(hiddev, cmd, user_arg);
 661                 else
 662                         r = -ENODEV;
 663                 mutex_unlock(&hiddev->existancelock);
 664                 return r;
 665
 666         case HIDIOCINITREPORT:
 667                 mutex_lock(&hiddev->existancelock);
 668                 if (!hiddev->exist) {
 669                         mutex_unlock(&hiddev->existancelock);
 670                         return -ENODEV;
 671                 }
 672                 usbhid_init_reports(hid);
 673                 mutex_unlock(&hiddev->existancelock);
 674
 675                 return 0;
 676
 677         case HIDIOCGREPORT:
 678                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
 679                         return -EFAULT;
 680
 681                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
 682                         return -EINVAL;
 683
 684                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 685                         return -EINVAL;
 686
 687                 mutex_lock(&hiddev->existancelock);
 688                 if (hiddev->exist) {
 689                         usbhid_submit_report(hid, report, USB_DIR_IN);
 690                         usbhid_wait_io(hid);
 691                 }
 692                 mutex_unlock(&hiddev->existancelock);
 693
 694                 return 0;
 695
 696         case HIDIOCSREPORT:
 697                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
 698                         return -EFAULT;
 699
 700                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
 701                         return -EINVAL;
 702
 703                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 704                         return -EINVAL;
 705
 706                 mutex_lock(&hiddev->existancelock);
 707                 if (hiddev->exist) {
 708                         usbhid_submit_report(hid, report, USB_DIR_OUT);
 709                         usbhid_wait_io(hid);
 710                 }
 711                 mutex_unlock(&hiddev->existancelock);
 712
 713                 return 0;
 714
 715         case HIDIOCGREPORTINFO:
 716                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
 717                         return -EFAULT;
 718
 719                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 720                         return -EINVAL;
 721
 722                 rinfo.num_fields = report->maxfield;
 723
 724                 if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
 725                         return -EFAULT;
 726
 727                 return 0;
 728
 729         case HIDIOCGFIELDINFO:
 730                 if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
 731                         return -EFAULT;
 732                 rinfo.report_type = finfo.report_type;
 733                 rinfo.report_id = finfo.report_id;
 734                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 735                         return -EINVAL;
 736
 737                 if (finfo.field_index >= report->maxfield)
 738                         return -EINVAL;
 739
 740                 field = report->field[finfo.field_index];
 741                 memset(&finfo, 0, sizeof(finfo));
 742                 finfo.report_type = rinfo.report_type;
 743                 finfo.report_id = rinfo.report_id;
 744                 finfo.field_index = field->report_count - 1;
 745                 finfo.maxusage = field->maxusage;
 746                 finfo.flags = field->flags;
 747                 finfo.physical = field->physical;
 748                 finfo.logical = field->logical;
 749                 finfo.application = field->application;
 750                 finfo.logical_minimum = field->logical_minimum;
 751                 finfo.logical_maximum = field->logical_maximum;
 752                 finfo.physical_minimum = field->physical_minimum;
 753                 finfo.physical_maximum = field->physical_maximum;
 754                 finfo.unit_exponent = field->unit_exponent;
 755                 finfo.unit = field->unit;
 756
 757                 if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
 758                         return -EFAULT;
 759
 760                 return 0;
 761
 762         case HIDIOCGUCODE:
 763                 /* fall through */
 764         case HIDIOCGUSAGE:
 765         case HIDIOCSUSAGE:
 766         case HIDIOCGUSAGES:
 767         case HIDIOCSUSAGES:
 768         case HIDIOCGCOLLECTIONINDEX:
 769                 mutex_lock(&hiddev->existancelock);
 770                 if (hiddev->exist)
 771                         r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
 772                 else
 773                         r = -ENODEV;
 774                 mutex_unlock(&hiddev->existancelock);
 775                 return r;
 776
 777         case HIDIOCGCOLLECTIONINFO:
 778                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
 779                         return -EFAULT;
 780
 781                 if (cinfo.index >= hid->maxcollection)
 782                         return -EINVAL;
 783
 784                 cinfo.type = hid->collection[cinfo.index].type;
 785                 cinfo.usage = hid->collection[cinfo.index].usage;
 786                 cinfo.level = hid->collection[cinfo.index].level;
 787
 788                 if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
 789                         return -EFAULT;
 790                 return 0;
 791
 792         default:
 793
 794                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
 795                         return -EINVAL;
 796
 797                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
 798                         int len;
 799                         if (!hid->name)
 800                                 return 0;
 801                         len = strlen(hid->name) + 1;
 802                         if (len > _IOC_SIZE(cmd))
 803                                  len = _IOC_SIZE(cmd);
 804                         return copy_to_user(user_arg, hid->name, len) ?
 805                                 -EFAULT : len;
 806                 }
 807
 808                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
 809                         int len;
 810                         if (!hid->phys)
 811                                 return 0;
 812                         len = strlen(hid->phys) + 1;
 813                         if (len > _IOC_SIZE(cmd))
 814                                 len = _IOC_SIZE(cmd);
 815                         return copy_to_user(user_arg, hid->phys, len) ?
 816                                 -EFAULT : len;
 817                 }
 818         }
 819         return -EINVAL;
 820 }
 821
 822 #ifdef CONFIG_COMPAT
 823 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 824 {
 825         return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
 826 }
 827 #endif
 828
 829 static const struct file_operations hiddev_fops = {
 830         .owner =        THIS_MODULE,
 831         .read =         hiddev_read,
 832         .write =        hiddev_write,
 833         .poll =         hiddev_poll,
 834         .open =         hiddev_open,
 835         .release =      hiddev_release,
 836         .unlocked_ioctl =       hiddev_ioctl,
 837         .fasync =       hiddev_fasync,
 838 #ifdef CONFIG_COMPAT
 839         .compat_ioctl   = hiddev_compat_ioctl,
 840 #endif
 841 };
 842
 843 static struct usb_class_driver hiddev_class = {
 844         .name =         "hiddev%d",
 845         .fops =         &hiddev_fops,
 846         .minor_base =   HIDDEV_MINOR_BASE,
 847 };
 848
 849 /*
 850  * This is where hid.c calls us to connect a hid device to the hiddev driver
 851  */
 852 int hiddev_connect(struct hid_device *hid, unsigned int force)
 853 {
 854         struct hiddev *hiddev;
 855         struct usbhid_device *usbhid = hid->driver_data;
 856         int retval;
 857
 858         if (!force) {
 859                 unsigned int i;
 860                 for (i = 0; i < hid->maxcollection; i++)
 861                         if (hid->collection[i].type ==
 862                             HID_COLLECTION_APPLICATION &&
 863                             !IS_INPUT_APPLICATION(hid->collection[i].usage))
 864                                 break;
 865
 866                 if (i == hid->maxcollection)
 867                         return -1;
 868         }
 869
 870         if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
 871                 return -1;
 872
 873         init_waitqueue_head(&hiddev->wait);
 874         INIT_LIST_HEAD(&hiddev->list);
 875         spin_lock_init(&hiddev->list_lock);
 876         mutex_init(&hiddev->existancelock);
 877         hid->hiddev = hiddev;
 878         hiddev->hid = hid;
 879         hiddev->exist = 1;
 880
 881         retval = usb_register_dev(usbhid->intf, &hiddev_class);
 882         if (retval) {
 883                 err_hid("Not able to get a minor for this device.");
 884                 hid->hiddev = NULL;
 885                 kfree(hiddev);
 886                 return -1;
 887         } else {
 888                 hid->minor = usbhid->intf->minor;
 889                 hiddev_table[usbhid->intf->minor - HIDDEV_MINOR_BASE] = hiddev;
 890         }
 891
 892         return 0;
 893 }
 894
 895 /*
 896  * This is where hid.c calls us to disconnect a hiddev device from the
 897  * corresponding hid device (usually because the usb device has disconnected)
 898  */
 899 static struct usb_class_driver hiddev_class;
 900 void hiddev_disconnect(struct hid_device *hid)
 901 {
 902         struct hiddev *hiddev = hid->hiddev;
 903         struct usbhid_device *usbhid = hid->driver_data;
 904
 905         mutex_lock(&hiddev->existancelock);
 906         hiddev->exist = 0;
 907         mutex_unlock(&hiddev->existancelock);
 908
 909         hiddev_table[hiddev->hid->minor - HIDDEV_MINOR_BASE] = NULL;
 910         usb_deregister_dev(usbhid->intf, &hiddev_class);
 911
 912         if (hiddev->open) {
 913                 usbhid_close(hiddev->hid);
 914                 wake_up_interruptible(&hiddev->wait);
 915         } else {
 916                 kfree(hiddev);
 917         }
 918 }
 919
 920 /* Currently this driver is a USB driver.  It's not a conventional one in
 921  * the sense that it doesn't probe at the USB level.  Instead it waits to
 922  * be connected by HID through the hiddev_connect / hiddev_disconnect
 923  * routines.  The reason to register as a USB device is to gain part of the
 924  * minor number space from the USB major.
 925  *
 926  * In theory, should the HID code be generalized to more than one physical
 927  * medium (say, IEEE 1384), this driver will probably need to register its
 928  * own major number, and in doing so, no longer need to register with USB.
 929  * At that point the probe routine and hiddev_driver struct below will no
 930  * longer be useful.
 931  */
 932
 933
 934 /* We never attach in this manner, and rely on HID to connect us.  This
 935  * is why there is no disconnect routine defined in the usb_driver either.
 936  */
 937 static int hiddev_usbd_probe(struct usb_interface *intf,
 938                              const struct usb_device_id *hiddev_info)
 939 {
 940         return -ENODEV;
 941 }
 942
 943
 944 static /* const */ struct usb_driver hiddev_driver = {
 945         .name =         "hiddev",
 946         .probe =        hiddev_usbd_probe,
 947 };
 948
 949 int __init hiddev_init(void)
 950 {
 951         return usb_register(&hiddev_driver);
 952 }
 953
 954 void hiddev_exit(void)
 955 {
 956         usb_deregister(&hiddev_driver);
 957 }