d73eea382ab3879c93a0c74db2833d47ead87f6f
[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         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 }