Merge ssh://master.kernel.org/pub/scm/linux/kernel/git/sam/kbuild
[linux-2.6] / 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         wait_queue_head_t wait;
53         struct hid_device *hid;
54         struct list_head list;
55         spinlock_t list_lock;
56 };
57
58 struct hiddev_list {
59         struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
60         int head;
61         int tail;
62         unsigned flags;
63         struct fasync_struct *fasync;
64         struct hiddev *hiddev;
65         struct list_head node;
66 };
67
68 static struct hiddev *hiddev_table[HIDDEV_MINORS];
69
70 /*
71  * Find a report, given the report's type and ID.  The ID can be specified
72  * indirectly by REPORT_ID_FIRST (which returns the first report of the given
73  * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
74  * given type which follows old_id.
75  */
76 static struct hid_report *
77 hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
78 {
79         unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
80         unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK;
81         struct hid_report_enum *report_enum;
82         struct hid_report *report;
83         struct list_head *list;
84
85         if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
86             rinfo->report_type > HID_REPORT_TYPE_MAX)
87                 return NULL;
88
89         report_enum = hid->report_enum +
90                 (rinfo->report_type - HID_REPORT_TYPE_MIN);
91
92         switch (flags) {
93         case 0: /* Nothing to do -- report_id is already set correctly */
94                 break;
95
96         case HID_REPORT_ID_FIRST:
97                 if (list_empty(&report_enum->report_list))
98                         return NULL;
99
100                 list = report_enum->report_list.next;
101                 report = list_entry(list, struct hid_report, list);
102                 rinfo->report_id = report->id;
103                 break;
104
105         case HID_REPORT_ID_NEXT:
106                 report = report_enum->report_id_hash[rid];
107                 if (!report)
108                         return NULL;
109
110                 list = report->list.next;
111                 if (list == &report_enum->report_list)
112                         return NULL;
113
114                 report = list_entry(list, struct hid_report, list);
115                 rinfo->report_id = report->id;
116                 break;
117
118         default:
119                 return NULL;
120         }
121
122         return report_enum->report_id_hash[rinfo->report_id];
123 }
124
125 /*
126  * Perform an exhaustive search of the report table for a usage, given its
127  * type and usage id.
128  */
129 static struct hid_field *
130 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
131 {
132         int i, j;
133         struct hid_report *report;
134         struct hid_report_enum *report_enum;
135         struct hid_field *field;
136
137         if (uref->report_type < HID_REPORT_TYPE_MIN ||
138             uref->report_type > HID_REPORT_TYPE_MAX)
139                 return NULL;
140
141         report_enum = hid->report_enum +
142                 (uref->report_type - HID_REPORT_TYPE_MIN);
143
144         list_for_each_entry(report, &report_enum->report_list, list) {
145                 for (i = 0; i < report->maxfield; i++) {
146                         field = report->field[i];
147                         for (j = 0; j < field->maxusage; j++) {
148                                 if (field->usage[j].hid == uref->usage_code) {
149                                         uref->report_id = report->id;
150                                         uref->field_index = i;
151                                         uref->usage_index = j;
152                                         return field;
153                                 }
154                         }
155                 }
156         }
157
158         return NULL;
159 }
160
161 static void hiddev_send_event(struct hid_device *hid,
162                               struct hiddev_usage_ref *uref)
163 {
164         struct hiddev *hiddev = hid->hiddev;
165         struct hiddev_list *list;
166         unsigned long flags;
167
168         spin_lock_irqsave(&hiddev->list_lock, flags);
169         list_for_each_entry(list, &hiddev->list, node) {
170                 if (uref->field_index != HID_FIELD_INDEX_NONE ||
171                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
172                         list->buffer[list->head] = *uref;
173                         list->head = (list->head + 1) &
174                                 (HIDDEV_BUFFER_SIZE - 1);
175                         kill_fasync(&list->fasync, SIGIO, POLL_IN);
176                 }
177         }
178         spin_unlock_irqrestore(&hiddev->list_lock, flags);
179
180         wake_up_interruptible(&hiddev->wait);
181 }
182
183 /*
184  * This is where hid.c calls into hiddev to pass an event that occurred over
185  * the interrupt pipe
186  */
187 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
188                       struct hid_usage *usage, __s32 value)
189 {
190         unsigned type = field->report_type;
191         struct hiddev_usage_ref uref;
192
193         uref.report_type =
194           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
195           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
196            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
197         uref.report_id = field->report->id;
198         uref.field_index = field->index;
199         uref.usage_index = (usage - field->usage);
200         uref.usage_code = usage->hid;
201         uref.value = value;
202
203         hiddev_send_event(hid, &uref);
204 }
205 EXPORT_SYMBOL_GPL(hiddev_hid_event);
206
207 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
208 {
209         unsigned type = report->type;
210         struct hiddev_usage_ref uref;
211
212         memset(&uref, 0, sizeof(uref));
213         uref.report_type =
214           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
215           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
216            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
217         uref.report_id = report->id;
218         uref.field_index = HID_FIELD_INDEX_NONE;
219
220         hiddev_send_event(hid, &uref);
221 }
222
223 /*
224  * fasync file op
225  */
226 static int hiddev_fasync(int fd, struct file *file, int on)
227 {
228         int retval;
229         struct hiddev_list *list = file->private_data;
230
231         retval = fasync_helper(fd, file, on, &list->fasync);
232
233         return retval < 0 ? retval : 0;
234 }
235
236
237 /*
238  * release file op
239  */
240 static int hiddev_release(struct inode * inode, struct file * file)
241 {
242         struct hiddev_list *list = file->private_data;
243         unsigned long flags;
244
245         hiddev_fasync(-1, file, 0);
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         unsigned long flags;
270
271         int i = iminor(inode) - HIDDEV_MINOR_BASE;
272
273         if (i >= HIDDEV_MINORS || !hiddev_table[i])
274                 return -ENODEV;
275
276         if (!(list = kzalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
277                 return -ENOMEM;
278
279         list->hiddev = hiddev_table[i];
280
281         spin_lock_irqsave(&list->hiddev->list_lock, flags);
282         list_add_tail(&list->node, &hiddev_table[i]->list);
283         spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
284
285         file->private_data = list;
286
287         if (!list->hiddev->open++)
288                 if (list->hiddev->exist)
289                         usbhid_open(hiddev_table[i]->hid);
290
291         return 0;
292 }
293
294 /*
295  * "write" file op
296  */
297 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
298 {
299         return -EINVAL;
300 }
301
302 /*
303  * "read" file op
304  */
305 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
306 {
307         DECLARE_WAITQUEUE(wait, current);
308         struct hiddev_list *list = file->private_data;
309         int event_size;
310         int retval = 0;
311
312         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
313                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
314
315         if (count < event_size)
316                 return 0;
317
318         while (retval == 0) {
319                 if (list->head == list->tail) {
320                         add_wait_queue(&list->hiddev->wait, &wait);
321                         set_current_state(TASK_INTERRUPTIBLE);
322
323                         while (list->head == list->tail) {
324                                 if (file->f_flags & O_NONBLOCK) {
325                                         retval = -EAGAIN;
326                                         break;
327                                 }
328                                 if (signal_pending(current)) {
329                                         retval = -ERESTARTSYS;
330                                         break;
331                                 }
332                                 if (!list->hiddev->exist) {
333                                         retval = -EIO;
334                                         break;
335                                 }
336
337                                 schedule();
338                                 set_current_state(TASK_INTERRUPTIBLE);
339                         }
340
341                         set_current_state(TASK_RUNNING);
342                         remove_wait_queue(&list->hiddev->wait, &wait);
343                 }
344
345                 if (retval)
346                         return retval;
347
348
349                 while (list->head != list->tail &&
350                        retval + event_size <= count) {
351                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
352                                 if (list->buffer[list->tail].field_index !=
353                                     HID_FIELD_INDEX_NONE) {
354                                         struct hiddev_event event;
355                                         event.hid = list->buffer[list->tail].usage_code;
356                                         event.value = list->buffer[list->tail].value;
357                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event)))
358                                                 return -EFAULT;
359                                         retval += sizeof(struct hiddev_event);
360                                 }
361                         } else {
362                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
363                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
364                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref)))
365                                                 return -EFAULT;
366                                         retval += sizeof(struct hiddev_usage_ref);
367                                 }
368                         }
369                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
370                 }
371
372         }
373
374         return retval;
375 }
376
377 /*
378  * "poll" file op
379  * No kernel lock - fine
380  */
381 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
382 {
383         struct hiddev_list *list = file->private_data;
384
385         poll_wait(file, &list->hiddev->wait, wait);
386         if (list->head != list->tail)
387                 return POLLIN | POLLRDNORM;
388         if (!list->hiddev->exist)
389                 return POLLERR | POLLHUP;
390         return 0;
391 }
392
393 /*
394  * "ioctl" file op
395  */
396 static int hiddev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
397 {
398         struct hiddev_list *list = file->private_data;
399         struct hiddev *hiddev = list->hiddev;
400         struct hid_device *hid = hiddev->hid;
401         struct usb_device *dev = hid_to_usb_dev(hid);
402         struct hiddev_collection_info cinfo;
403         struct hiddev_report_info rinfo;
404         struct hiddev_field_info finfo;
405         struct hiddev_usage_ref_multi *uref_multi = NULL;
406         struct hiddev_usage_ref *uref;
407         struct hiddev_devinfo dinfo;
408         struct hid_report *report;
409         struct hid_field *field;
410         struct usbhid_device *usbhid = hid->driver_data;
411         void __user *user_arg = (void __user *)arg;
412         int i;
413
414         if (!hiddev->exist)
415                 return -EIO;
416
417         switch (cmd) {
418
419         case HIDIOCGVERSION:
420                 return put_user(HID_VERSION, (int __user *)arg);
421
422         case HIDIOCAPPLICATION:
423                 if (arg < 0 || arg >= hid->maxapplication)
424                         return -EINVAL;
425
426                 for (i = 0; i < hid->maxcollection; i++)
427                         if (hid->collection[i].type ==
428                             HID_COLLECTION_APPLICATION && arg-- == 0)
429                                 break;
430
431                 if (i == hid->maxcollection)
432                         return -EINVAL;
433
434                 return hid->collection[i].usage;
435
436         case HIDIOCGDEVINFO:
437                 dinfo.bustype = BUS_USB;
438                 dinfo.busnum = dev->bus->busnum;
439                 dinfo.devnum = dev->devnum;
440                 dinfo.ifnum = usbhid->ifnum;
441                 dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
442                 dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
443                 dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
444                 dinfo.num_applications = hid->maxapplication;
445                 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
446                         return -EFAULT;
447
448                 return 0;
449
450         case HIDIOCGFLAG:
451                 if (put_user(list->flags, (int __user *)arg))
452                         return -EFAULT;
453
454                 return 0;
455
456         case HIDIOCSFLAG:
457                 {
458                         int newflags;
459                         if (get_user(newflags, (int __user *)arg))
460                                 return -EFAULT;
461
462                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
463                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
464                              (newflags & HIDDEV_FLAG_UREF) == 0))
465                                 return -EINVAL;
466
467                         list->flags = newflags;
468
469                         return 0;
470                 }
471
472         case HIDIOCGSTRING:
473                 {
474                         int idx, len;
475                         char *buf;
476
477                         if (get_user(idx, (int __user *)arg))
478                                 return -EFAULT;
479
480                         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
481                                 return -ENOMEM;
482
483                         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
484                                 kfree(buf);
485                                 return -EINVAL;
486                         }
487
488                         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
489                                 kfree(buf);
490                                 return -EFAULT;
491                         }
492
493                         kfree(buf);
494
495                         return len;
496                 }
497
498         case HIDIOCINITREPORT:
499                 usbhid_init_reports(hid);
500
501                 return 0;
502
503         case HIDIOCGREPORT:
504                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
505                         return -EFAULT;
506
507                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
508                         return -EINVAL;
509
510                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
511                         return -EINVAL;
512
513                 usbhid_submit_report(hid, report, USB_DIR_IN);
514                 usbhid_wait_io(hid);
515
516                 return 0;
517
518         case HIDIOCSREPORT:
519                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
520                         return -EFAULT;
521
522                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
523                         return -EINVAL;
524
525                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
526                         return -EINVAL;
527
528                 usbhid_submit_report(hid, report, USB_DIR_OUT);
529                 usbhid_wait_io(hid);
530
531                 return 0;
532
533         case HIDIOCGREPORTINFO:
534                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
535                         return -EFAULT;
536
537                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
538                         return -EINVAL;
539
540                 rinfo.num_fields = report->maxfield;
541
542                 if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
543                         return -EFAULT;
544
545                 return 0;
546
547         case HIDIOCGFIELDINFO:
548                 if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
549                         return -EFAULT;
550                 rinfo.report_type = finfo.report_type;
551                 rinfo.report_id = finfo.report_id;
552                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
553                         return -EINVAL;
554
555                 if (finfo.field_index >= report->maxfield)
556                         return -EINVAL;
557
558                 field = report->field[finfo.field_index];
559                 memset(&finfo, 0, sizeof(finfo));
560                 finfo.report_type = rinfo.report_type;
561                 finfo.report_id = rinfo.report_id;
562                 finfo.field_index = field->report_count - 1;
563                 finfo.maxusage = field->maxusage;
564                 finfo.flags = field->flags;
565                 finfo.physical = field->physical;
566                 finfo.logical = field->logical;
567                 finfo.application = field->application;
568                 finfo.logical_minimum = field->logical_minimum;
569                 finfo.logical_maximum = field->logical_maximum;
570                 finfo.physical_minimum = field->physical_minimum;
571                 finfo.physical_maximum = field->physical_maximum;
572                 finfo.unit_exponent = field->unit_exponent;
573                 finfo.unit = field->unit;
574
575                 if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
576                         return -EFAULT;
577
578                 return 0;
579
580         case HIDIOCGUCODE:
581                 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
582                 if (!uref_multi)
583                         return -ENOMEM;
584                 uref = &uref_multi->uref;
585                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
586                         goto fault;
587
588                 rinfo.report_type = uref->report_type;
589                 rinfo.report_id = uref->report_id;
590                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
591                         goto inval;
592
593                 if (uref->field_index >= report->maxfield)
594                         goto inval;
595
596                 field = report->field[uref->field_index];
597                 if (uref->usage_index >= field->maxusage)
598                         goto inval;
599
600                 uref->usage_code = field->usage[uref->usage_index].hid;
601
602                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
603                         goto fault;
604
605                 kfree(uref_multi);
606                 return 0;
607
608         case HIDIOCGUSAGE:
609         case HIDIOCSUSAGE:
610         case HIDIOCGUSAGES:
611         case HIDIOCSUSAGES:
612         case HIDIOCGCOLLECTIONINDEX:
613                 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
614                 if (!uref_multi)
615                         return -ENOMEM;
616                 uref = &uref_multi->uref;
617                 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
618                         if (copy_from_user(uref_multi, user_arg,
619                                            sizeof(*uref_multi)))
620                                 goto fault;
621                 } else {
622                         if (copy_from_user(uref, user_arg, sizeof(*uref)))
623                                 goto fault;
624                 }
625
626                 if (cmd != HIDIOCGUSAGE &&
627                     cmd != HIDIOCGUSAGES &&
628                     uref->report_type == HID_REPORT_TYPE_INPUT)
629                         goto inval;
630
631                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
632                         field = hiddev_lookup_usage(hid, uref);
633                         if (field == NULL)
634                                 goto inval;
635                 } else {
636                         rinfo.report_type = uref->report_type;
637                         rinfo.report_id = uref->report_id;
638                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
639                                 goto inval;
640
641                         if (uref->field_index >= report->maxfield)
642                                 goto inval;
643
644                         field = report->field[uref->field_index];
645
646                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
647                                 if (uref->usage_index >= field->maxusage)
648                                         goto inval;
649                         } else if (uref->usage_index >= field->report_count)
650                                 goto inval;
651
652                         else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
653                                  (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
654                                   uref->usage_index + uref_multi->num_values > field->report_count))
655                                 goto inval;
656                         }
657
658                 switch (cmd) {
659                         case HIDIOCGUSAGE:
660                                 uref->value = field->value[uref->usage_index];
661                                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
662                                         goto fault;
663                                 goto goodreturn;
664
665                         case HIDIOCSUSAGE:
666                                 field->value[uref->usage_index] = uref->value;
667                                 goto goodreturn;
668
669                         case HIDIOCGCOLLECTIONINDEX:
670                                 kfree(uref_multi);
671                                 return field->usage[uref->usage_index].collection_index;
672                         case HIDIOCGUSAGES:
673                                 for (i = 0; i < uref_multi->num_values; i++)
674                                         uref_multi->values[i] =
675                                             field->value[uref->usage_index + i];
676                                 if (copy_to_user(user_arg, uref_multi,
677                                                  sizeof(*uref_multi)))
678                                         goto fault;
679                                 goto goodreturn;
680                         case HIDIOCSUSAGES:
681                                 for (i = 0; i < uref_multi->num_values; i++)
682                                         field->value[uref->usage_index + i] =
683                                             uref_multi->values[i];
684                                 goto goodreturn;
685                 }
686
687 goodreturn:
688                 kfree(uref_multi);
689                 return 0;
690 fault:
691                 kfree(uref_multi);
692                 return -EFAULT;
693 inval:
694                 kfree(uref_multi);
695                 return -EINVAL;
696
697         case HIDIOCGCOLLECTIONINFO:
698                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
699                         return -EFAULT;
700
701                 if (cinfo.index >= hid->maxcollection)
702                         return -EINVAL;
703
704                 cinfo.type = hid->collection[cinfo.index].type;
705                 cinfo.usage = hid->collection[cinfo.index].usage;
706                 cinfo.level = hid->collection[cinfo.index].level;
707
708                 if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
709                         return -EFAULT;
710                 return 0;
711
712         default:
713
714                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
715                         return -EINVAL;
716
717                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
718                         int len;
719                         if (!hid->name)
720                                 return 0;
721                         len = strlen(hid->name) + 1;
722                         if (len > _IOC_SIZE(cmd))
723                                  len = _IOC_SIZE(cmd);
724                         return copy_to_user(user_arg, hid->name, len) ?
725                                 -EFAULT : len;
726                 }
727
728                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
729                         int len;
730                         if (!hid->phys)
731                                 return 0;
732                         len = strlen(hid->phys) + 1;
733                         if (len > _IOC_SIZE(cmd))
734                                 len = _IOC_SIZE(cmd);
735                         return copy_to_user(user_arg, hid->phys, len) ?
736                                 -EFAULT : len;
737                 }
738         }
739         return -EINVAL;
740 }
741
742 #ifdef CONFIG_COMPAT
743 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
744 {
745         struct inode *inode = file->f_path.dentry->d_inode;
746         return hiddev_ioctl(inode, file, cmd, compat_ptr(arg));
747 }
748 #endif
749
750 static const struct file_operations hiddev_fops = {
751         .owner =        THIS_MODULE,
752         .read =         hiddev_read,
753         .write =        hiddev_write,
754         .poll =         hiddev_poll,
755         .open =         hiddev_open,
756         .release =      hiddev_release,
757         .ioctl =        hiddev_ioctl,
758         .fasync =       hiddev_fasync,
759 #ifdef CONFIG_COMPAT
760         .compat_ioctl   = hiddev_compat_ioctl,
761 #endif
762 };
763
764 static struct usb_class_driver hiddev_class = {
765         .name =         "hiddev%d",
766         .fops =         &hiddev_fops,
767         .minor_base =   HIDDEV_MINOR_BASE,
768 };
769
770 /*
771  * This is where hid.c calls us to connect a hid device to the hiddev driver
772  */
773 int hiddev_connect(struct hid_device *hid)
774 {
775         struct hiddev *hiddev;
776         struct usbhid_device *usbhid = hid->driver_data;
777         int i;
778         int retval;
779
780         for (i = 0; i < hid->maxcollection; i++)
781                 if (hid->collection[i].type ==
782                     HID_COLLECTION_APPLICATION &&
783                     !IS_INPUT_APPLICATION(hid->collection[i].usage))
784                         break;
785
786         if (i == hid->maxcollection && (hid->quirks & HID_QUIRK_HIDDEV) == 0)
787                 return -1;
788
789         if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
790                 return -1;
791
792         retval = usb_register_dev(usbhid->intf, &hiddev_class);
793         if (retval) {
794                 err_hid("Not able to get a minor for this device.");
795                 kfree(hiddev);
796                 return -1;
797         }
798
799         init_waitqueue_head(&hiddev->wait);
800         INIT_LIST_HEAD(&hiddev->list);
801         spin_lock_init(&hiddev->list_lock);
802         hiddev->hid = hid;
803         hiddev->exist = 1;
804
805         hid->minor = usbhid->intf->minor;
806         hid->hiddev = hiddev;
807
808         hiddev_table[usbhid->intf->minor - HIDDEV_MINOR_BASE] = hiddev;
809
810         return 0;
811 }
812
813 /*
814  * This is where hid.c calls us to disconnect a hiddev device from the
815  * corresponding hid device (usually because the usb device has disconnected)
816  */
817 static struct usb_class_driver hiddev_class;
818 void hiddev_disconnect(struct hid_device *hid)
819 {
820         struct hiddev *hiddev = hid->hiddev;
821         struct usbhid_device *usbhid = hid->driver_data;
822
823         hiddev->exist = 0;
824
825         hiddev_table[hiddev->hid->minor - HIDDEV_MINOR_BASE] = NULL;
826         usb_deregister_dev(usbhid->intf, &hiddev_class);
827
828         if (hiddev->open) {
829                 usbhid_close(hiddev->hid);
830                 wake_up_interruptible(&hiddev->wait);
831         } else {
832                 kfree(hiddev);
833         }
834 }
835
836 /* Currently this driver is a USB driver.  It's not a conventional one in
837  * the sense that it doesn't probe at the USB level.  Instead it waits to
838  * be connected by HID through the hiddev_connect / hiddev_disconnect
839  * routines.  The reason to register as a USB device is to gain part of the
840  * minor number space from the USB major.
841  *
842  * In theory, should the HID code be generalized to more than one physical
843  * medium (say, IEEE 1384), this driver will probably need to register its
844  * own major number, and in doing so, no longer need to register with USB.
845  * At that point the probe routine and hiddev_driver struct below will no
846  * longer be useful.
847  */
848
849
850 /* We never attach in this manner, and rely on HID to connect us.  This
851  * is why there is no disconnect routine defined in the usb_driver either.
852  */
853 static int hiddev_usbd_probe(struct usb_interface *intf,
854                              const struct usb_device_id *hiddev_info)
855 {
856         return -ENODEV;
857 }
858
859
860 static /* const */ struct usb_driver hiddev_driver = {
861         .name =         "hiddev",
862         .probe =        hiddev_usbd_probe,
863 };
864
865 int __init hiddev_init(void)
866 {
867         return usb_register(&hiddev_driver);
868 }
869
870 void hiddev_exit(void)
871 {
872         usb_deregister(&hiddev_driver);
873 }