Merge branch 'bkl-removal' of git://git.lwn.net/linux-2.6
[linux-2.6.git] / 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         struct hiddev_list *list = file->private_data;
231
232         return fasync_helper(fd, file, on, &list->fasync);
233 }
234
235
236 /*
237  * release file op
238  */
239 static int hiddev_release(struct inode * inode, struct file * file)
240 {
241         struct hiddev_list *list = file->private_data;
242         unsigned long flags;
243
244         spin_lock_irqsave(&list->hiddev->list_lock, flags);
245         list_del(&list->node);
246         spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
247
248         if (!--list->hiddev->open) {
249                 if (list->hiddev->exist)
250                         usbhid_close(list->hiddev->hid);
251                 else
252                         kfree(list->hiddev);
253         }
254
255         kfree(list);
256
257         return 0;
258 }
259
260 /*
261  * open file op
262  */
263 static int hiddev_open(struct inode *inode, struct file *file)
264 {
265         struct hiddev_list *list;
266         int res;
267
268         int i = iminor(inode) - HIDDEV_MINOR_BASE;
269
270         if (i >= HIDDEV_MINORS || i < 0 || !hiddev_table[i])
271                 return -ENODEV;
272
273         if (!(list = kzalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
274                 return -ENOMEM;
275         mutex_init(&list->thread_lock);
276
277         list->hiddev = hiddev_table[i];
278
279
280         file->private_data = list;
281
282         /*
283          * no need for locking because the USB major number
284          * is shared which usbcore guards against disconnect
285          */
286         if (list->hiddev->exist) {
287                 if (!list->hiddev->open++) {
288                         res = usbhid_open(hiddev_table[i]->hid);
289                         if (res < 0) {
290                                 res = -EIO;
291                                 goto bail;
292                         }
293                 }
294         } else {
295                 res = -ENODEV;
296                 goto bail;
297         }
298
299         spin_lock_irq(&list->hiddev->list_lock);
300         list_add_tail(&list->node, &hiddev_table[i]->list);
301         spin_unlock_irq(&list->hiddev->list_lock);
302
303         return 0;
304 bail:
305         file->private_data = NULL;
306         kfree(list);
307         return res;
308 }
309
310 /*
311  * "write" file op
312  */
313 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
314 {
315         return -EINVAL;
316 }
317
318 /*
319  * "read" file op
320  */
321 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
322 {
323         DEFINE_WAIT(wait);
324         struct hiddev_list *list = file->private_data;
325         int event_size;
326         int retval;
327
328         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
329                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
330
331         if (count < event_size)
332                 return 0;
333
334         /* lock against other threads */
335         retval = mutex_lock_interruptible(&list->thread_lock);
336         if (retval)
337                 return -ERESTARTSYS;
338
339         while (retval == 0) {
340                 if (list->head == list->tail) {
341                         prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);
342
343                         while (list->head == list->tail) {
344                                 if (file->f_flags & O_NONBLOCK) {
345                                         retval = -EAGAIN;
346                                         break;
347                                 }
348                                 if (signal_pending(current)) {
349                                         retval = -ERESTARTSYS;
350                                         break;
351                                 }
352                                 if (!list->hiddev->exist) {
353                                         retval = -EIO;
354                                         break;
355                                 }
356
357                                 /* let O_NONBLOCK tasks run */
358                                 mutex_unlock(&list->thread_lock);
359                                 schedule();
360                                 if (mutex_lock_interruptible(&list->thread_lock))
361                                         return -EINTR;
362                                 set_current_state(TASK_INTERRUPTIBLE);
363                         }
364                         finish_wait(&list->hiddev->wait, &wait);
365
366                 }
367
368                 if (retval) {
369                         mutex_unlock(&list->thread_lock);
370                         return retval;
371                 }
372
373
374                 while (list->head != list->tail &&
375                        retval + event_size <= count) {
376                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
377                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
378                                         struct hiddev_event event;
379
380                                         event.hid = list->buffer[list->tail].usage_code;
381                                         event.value = list->buffer[list->tail].value;
382                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {
383                                                 mutex_unlock(&list->thread_lock);
384                                                 return -EFAULT;
385                                         }
386                                         retval += sizeof(struct hiddev_event);
387                                 }
388                         } else {
389                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
390                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
391
392                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {
393                                                 mutex_unlock(&list->thread_lock);
394                                                 return -EFAULT;
395                                         }
396                                         retval += sizeof(struct hiddev_usage_ref);
397                                 }
398                         }
399                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
400                 }
401
402         }
403         mutex_unlock(&list->thread_lock);
404
405         return retval;
406 }
407
408 /*
409  * "poll" file op
410  * No kernel lock - fine
411  */
412 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
413 {
414         struct hiddev_list *list = file->private_data;
415
416         poll_wait(file, &list->hiddev->wait, wait);
417         if (list->head != list->tail)
418                 return POLLIN | POLLRDNORM;
419         if (!list->hiddev->exist)
420                 return POLLERR | POLLHUP;
421         return 0;
422 }
423
424 /*
425  * "ioctl" file op
426  */
427 static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
428 {
429         struct hid_device *hid = hiddev->hid;
430         struct hiddev_report_info rinfo;
431         struct hiddev_usage_ref_multi *uref_multi = NULL;
432         struct hiddev_usage_ref *uref;
433         struct hid_report *report;
434         struct hid_field *field;
435         int i;
436
437         uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
438         if (!uref_multi)
439                 return -ENOMEM;
440         lock_kernel();
441         uref = &uref_multi->uref;
442         if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
443                 if (copy_from_user(uref_multi, user_arg,
444                                    sizeof(*uref_multi)))
445                         goto fault;
446         } else {
447                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
448                         goto fault;
449         }
450
451         switch (cmd) {
452         case HIDIOCGUCODE:
453                 rinfo.report_type = uref->report_type;
454                 rinfo.report_id = uref->report_id;
455                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
456                         goto inval;
457
458                 if (uref->field_index >= report->maxfield)
459                         goto inval;
460
461                 field = report->field[uref->field_index];
462                 if (uref->usage_index >= field->maxusage)
463                         goto inval;
464
465                 uref->usage_code = field->usage[uref->usage_index].hid;
466
467                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
468                         goto fault;
469
470                 goto goodreturn;
471
472         default:
473                 if (cmd != HIDIOCGUSAGE &&
474                     cmd != HIDIOCGUSAGES &&
475                     uref->report_type == HID_REPORT_TYPE_INPUT)
476                         goto inval;
477
478                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
479                         field = hiddev_lookup_usage(hid, uref);
480                         if (field == NULL)
481                                 goto inval;
482                 } else {
483                         rinfo.report_type = uref->report_type;
484                         rinfo.report_id = uref->report_id;
485                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
486                                 goto inval;
487
488                         if (uref->field_index >= report->maxfield)
489                                 goto inval;
490
491                         field = report->field[uref->field_index];
492
493                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
494                                 if (uref->usage_index >= field->maxusage)
495                                         goto inval;
496                         } else if (uref->usage_index >= field->report_count)
497                                 goto inval;
498
499                         else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
500                                  (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
501                                   uref->usage_index + uref_multi->num_values > field->report_count))
502                                 goto inval;
503                         }
504
505                 switch (cmd) {
506                 case HIDIOCGUSAGE:
507                         uref->value = field->value[uref->usage_index];
508                         if (copy_to_user(user_arg, uref, sizeof(*uref)))
509                                 goto fault;
510                         goto goodreturn;
511
512                 case HIDIOCSUSAGE:
513                         field->value[uref->usage_index] = uref->value;
514                         goto goodreturn;
515
516                 case HIDIOCGCOLLECTIONINDEX:
517                         kfree(uref_multi);
518                         return field->usage[uref->usage_index].collection_index;
519                 case HIDIOCGUSAGES:
520                         for (i = 0; i < uref_multi->num_values; i++)
521                                 uref_multi->values[i] =
522                                     field->value[uref->usage_index + i];
523                         if (copy_to_user(user_arg, uref_multi,
524                                          sizeof(*uref_multi)))
525                                 goto fault;
526                         goto goodreturn;
527                 case HIDIOCSUSAGES:
528                         for (i = 0; i < uref_multi->num_values; i++)
529                                 field->value[uref->usage_index + i] =
530                                     uref_multi->values[i];
531                         goto goodreturn;
532                 }
533
534 goodreturn:
535                 unlock_kernel();
536                 kfree(uref_multi);
537                 return 0;
538 fault:
539                 unlock_kernel();
540                 kfree(uref_multi);
541                 return -EFAULT;
542 inval:
543                 unlock_kernel();
544                 kfree(uref_multi);
545                 return -EINVAL;
546         }
547 }
548
549 static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
550 {
551         struct hid_device *hid = hiddev->hid;
552         struct usb_device *dev = hid_to_usb_dev(hid);
553         int idx, len;
554         char *buf;
555
556         if (get_user(idx, (int __user *)user_arg))
557                 return -EFAULT;
558
559         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
560                 return -ENOMEM;
561
562         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
563                 kfree(buf);
564                 return -EINVAL;
565         }
566
567         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
568                 kfree(buf);
569                 return -EFAULT;
570         }
571
572         kfree(buf);
573
574         return len;
575 }
576
577 static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
578 {
579         struct hiddev_list *list = file->private_data;
580         struct hiddev *hiddev = list->hiddev;
581         struct hid_device *hid = hiddev->hid;
582         struct usb_device *dev = hid_to_usb_dev(hid);
583         struct hiddev_collection_info cinfo;
584         struct hiddev_report_info rinfo;
585         struct hiddev_field_info finfo;
586         struct hiddev_devinfo dinfo;
587         struct hid_report *report;
588         struct hid_field *field;
589         struct usbhid_device *usbhid = hid->driver_data;
590         void __user *user_arg = (void __user *)arg;
591         int i, r;
592         
593         /* Called without BKL by compat methods so no BKL taken */
594
595         /* FIXME: Who or what stop this racing with a disconnect ?? */
596         if (!hiddev->exist)
597                 return -EIO;
598
599         switch (cmd) {
600
601         case HIDIOCGVERSION:
602                 return put_user(HID_VERSION, (int __user *)arg);
603
604         case HIDIOCAPPLICATION:
605                 if (arg < 0 || arg >= hid->maxapplication)
606                         return -EINVAL;
607
608                 for (i = 0; i < hid->maxcollection; i++)
609                         if (hid->collection[i].type ==
610                             HID_COLLECTION_APPLICATION && arg-- == 0)
611                                 break;
612
613                 if (i == hid->maxcollection)
614                         return -EINVAL;
615
616                 return hid->collection[i].usage;
617
618         case HIDIOCGDEVINFO:
619                 dinfo.bustype = BUS_USB;
620                 dinfo.busnum = dev->bus->busnum;
621                 dinfo.devnum = dev->devnum;
622                 dinfo.ifnum = usbhid->ifnum;
623                 dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
624                 dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
625                 dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
626                 dinfo.num_applications = hid->maxapplication;
627                 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
628                         return -EFAULT;
629
630                 return 0;
631
632         case HIDIOCGFLAG:
633                 if (put_user(list->flags, (int __user *)arg))
634                         return -EFAULT;
635
636                 return 0;
637
638         case HIDIOCSFLAG:
639                 {
640                         int newflags;
641                         if (get_user(newflags, (int __user *)arg))
642                                 return -EFAULT;
643
644                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
645                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
646                              (newflags & HIDDEV_FLAG_UREF) == 0))
647                                 return -EINVAL;
648
649                         list->flags = newflags;
650
651                         return 0;
652                 }
653
654         case HIDIOCGSTRING:
655                 mutex_lock(&hiddev->existancelock);
656                 if (hiddev->exist)
657                         r = hiddev_ioctl_string(hiddev, cmd, user_arg);
658                 else
659                         r = -ENODEV;
660                 mutex_unlock(&hiddev->existancelock);
661                 return r;
662
663         case HIDIOCINITREPORT:
664                 mutex_lock(&hiddev->existancelock);
665                 if (!hiddev->exist) {
666                         mutex_unlock(&hiddev->existancelock);
667                         return -ENODEV;
668                 }
669                 usbhid_init_reports(hid);
670                 mutex_unlock(&hiddev->existancelock);
671
672                 return 0;
673
674         case HIDIOCGREPORT:
675                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
676                         return -EFAULT;
677
678                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
679                         return -EINVAL;
680
681                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
682                         return -EINVAL;
683
684                 mutex_lock(&hiddev->existancelock);
685                 if (hiddev->exist) {
686                         usbhid_submit_report(hid, report, USB_DIR_IN);
687                         usbhid_wait_io(hid);
688                 }
689                 mutex_unlock(&hiddev->existancelock);
690
691                 return 0;
692
693         case HIDIOCSREPORT:
694                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
695                         return -EFAULT;
696
697                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
698                         return -EINVAL;
699
700                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
701                         return -EINVAL;
702
703                 mutex_lock(&hiddev->existancelock);
704                 if (hiddev->exist) {
705                         usbhid_submit_report(hid, report, USB_DIR_OUT);
706                         usbhid_wait_io(hid);
707                 }
708                 mutex_unlock(&hiddev->existancelock);
709
710                 return 0;
711
712         case HIDIOCGREPORTINFO:
713                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
714                         return -EFAULT;
715
716                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
717                         return -EINVAL;
718
719                 rinfo.num_fields = report->maxfield;
720
721                 if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
722                         return -EFAULT;
723
724                 return 0;
725
726         case HIDIOCGFIELDINFO:
727                 if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
728                         return -EFAULT;
729                 rinfo.report_type = finfo.report_type;
730                 rinfo.report_id = finfo.report_id;
731                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
732                         return -EINVAL;
733
734                 if (finfo.field_index >= report->maxfield)
735                         return -EINVAL;
736
737                 field = report->field[finfo.field_index];
738                 memset(&finfo, 0, sizeof(finfo));
739                 finfo.report_type = rinfo.report_type;
740                 finfo.report_id = rinfo.report_id;
741                 finfo.field_index = field->report_count - 1;
742                 finfo.maxusage = field->maxusage;
743                 finfo.flags = field->flags;
744                 finfo.physical = field->physical;
745                 finfo.logical = field->logical;
746                 finfo.application = field->application;
747                 finfo.logical_minimum = field->logical_minimum;
748                 finfo.logical_maximum = field->logical_maximum;
749                 finfo.physical_minimum = field->physical_minimum;
750                 finfo.physical_maximum = field->physical_maximum;
751                 finfo.unit_exponent = field->unit_exponent;
752                 finfo.unit = field->unit;
753
754                 if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
755                         return -EFAULT;
756
757                 return 0;
758
759         case HIDIOCGUCODE:
760                 /* fall through */
761         case HIDIOCGUSAGE:
762         case HIDIOCSUSAGE:
763         case HIDIOCGUSAGES:
764         case HIDIOCSUSAGES:
765         case HIDIOCGCOLLECTIONINDEX:
766                 mutex_lock(&hiddev->existancelock);
767                 if (hiddev->exist)
768                         r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
769                 else
770                         r = -ENODEV;
771                 mutex_unlock(&hiddev->existancelock);
772                 return r;
773
774         case HIDIOCGCOLLECTIONINFO:
775                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
776                         return -EFAULT;
777
778                 if (cinfo.index >= hid->maxcollection)
779                         return -EINVAL;
780
781                 cinfo.type = hid->collection[cinfo.index].type;
782                 cinfo.usage = hid->collection[cinfo.index].usage;
783                 cinfo.level = hid->collection[cinfo.index].level;
784
785                 if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
786                         return -EFAULT;
787                 return 0;
788
789         default:
790
791                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
792                         return -EINVAL;
793
794                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
795                         int len;
796                         if (!hid->name)
797                                 return 0;
798                         len = strlen(hid->name) + 1;
799                         if (len > _IOC_SIZE(cmd))
800                                  len = _IOC_SIZE(cmd);
801                         return copy_to_user(user_arg, hid->name, len) ?
802                                 -EFAULT : len;
803                 }
804
805                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
806                         int len;
807                         if (!hid->phys)
808                                 return 0;
809                         len = strlen(hid->phys) + 1;
810                         if (len > _IOC_SIZE(cmd))
811                                 len = _IOC_SIZE(cmd);
812                         return copy_to_user(user_arg, hid->phys, len) ?
813                                 -EFAULT : len;
814                 }
815         }
816         return -EINVAL;
817 }
818
819 #ifdef CONFIG_COMPAT
820 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
821 {
822         return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
823 }
824 #endif
825
826 static const struct file_operations hiddev_fops = {
827         .owner =        THIS_MODULE,
828         .read =         hiddev_read,
829         .write =        hiddev_write,
830         .poll =         hiddev_poll,
831         .open =         hiddev_open,
832         .release =      hiddev_release,
833         .unlocked_ioctl =       hiddev_ioctl,
834         .fasync =       hiddev_fasync,
835 #ifdef CONFIG_COMPAT
836         .compat_ioctl   = hiddev_compat_ioctl,
837 #endif
838 };
839
840 static struct usb_class_driver hiddev_class = {
841         .name =         "hiddev%d",
842         .fops =         &hiddev_fops,
843         .minor_base =   HIDDEV_MINOR_BASE,
844 };
845
846 /*
847  * This is where hid.c calls us to connect a hid device to the hiddev driver
848  */
849 int hiddev_connect(struct hid_device *hid, unsigned int force)
850 {
851         struct hiddev *hiddev;
852         struct usbhid_device *usbhid = hid->driver_data;
853         int retval;
854
855         if (!force) {
856                 unsigned int i;
857                 for (i = 0; i < hid->maxcollection; i++)
858                         if (hid->collection[i].type ==
859                             HID_COLLECTION_APPLICATION &&
860                             !IS_INPUT_APPLICATION(hid->collection[i].usage))
861                                 break;
862
863                 if (i == hid->maxcollection)
864                         return -1;
865         }
866
867         if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
868                 return -1;
869
870         init_waitqueue_head(&hiddev->wait);
871         INIT_LIST_HEAD(&hiddev->list);
872         spin_lock_init(&hiddev->list_lock);
873         mutex_init(&hiddev->existancelock);
874         hid->hiddev = hiddev;
875         hiddev->hid = hid;
876         hiddev->exist = 1;
877
878         retval = usb_register_dev(usbhid->intf, &hiddev_class);
879         if (retval) {
880                 err_hid("Not able to get a minor for this device.");
881                 hid->hiddev = NULL;
882                 kfree(hiddev);
883                 return -1;
884         } else {
885                 hid->minor = usbhid->intf->minor;
886                 hiddev_table[usbhid->intf->minor - HIDDEV_MINOR_BASE] = hiddev;
887         }
888
889         return 0;
890 }
891
892 /*
893  * This is where hid.c calls us to disconnect a hiddev device from the
894  * corresponding hid device (usually because the usb device has disconnected)
895  */
896 static struct usb_class_driver hiddev_class;
897 void hiddev_disconnect(struct hid_device *hid)
898 {
899         struct hiddev *hiddev = hid->hiddev;
900         struct usbhid_device *usbhid = hid->driver_data;
901
902         mutex_lock(&hiddev->existancelock);
903         hiddev->exist = 0;
904         mutex_unlock(&hiddev->existancelock);
905
906         hiddev_table[hiddev->hid->minor - HIDDEV_MINOR_BASE] = NULL;
907         usb_deregister_dev(usbhid->intf, &hiddev_class);
908
909         if (hiddev->open) {
910                 usbhid_close(hiddev->hid);
911                 wake_up_interruptible(&hiddev->wait);
912         } else {
913                 kfree(hiddev);
914         }
915 }
916
917 /* Currently this driver is a USB driver.  It's not a conventional one in
918  * the sense that it doesn't probe at the USB level.  Instead it waits to
919  * be connected by HID through the hiddev_connect / hiddev_disconnect
920  * routines.  The reason to register as a USB device is to gain part of the
921  * minor number space from the USB major.
922  *
923  * In theory, should the HID code be generalized to more than one physical
924  * medium (say, IEEE 1384), this driver will probably need to register its
925  * own major number, and in doing so, no longer need to register with USB.
926  * At that point the probe routine and hiddev_driver struct below will no
927  * longer be useful.
928  */
929
930
931 /* We never attach in this manner, and rely on HID to connect us.  This
932  * is why there is no disconnect routine defined in the usb_driver either.
933  */
934 static int hiddev_usbd_probe(struct usb_interface *intf,
935                              const struct usb_device_id *hiddev_info)
936 {
937         return -ENODEV;
938 }
939
940
941 static /* const */ struct usb_driver hiddev_driver = {
942         .name =         "hiddev",
943         .probe =        hiddev_usbd_probe,
944 };
945
946 int __init hiddev_init(void)
947 {
948         return usb_register(&hiddev_driver);
949 }
950
951 void hiddev_exit(void)
952 {
953         usb_deregister(&hiddev_driver);
954 }