Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6
[linux-2.6] / drivers / usb / input / 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/config.h>
29 #include <linux/poll.h>
30 #include <linux/slab.h>
31 #include <linux/module.h>
32 #include <linux/init.h>
33 #include <linux/smp_lock.h>
34 #include <linux/input.h>
35 #include <linux/usb.h>
36 #include "hid.h"
37 #include <linux/hiddev.h>
38 #include <linux/devfs_fs_kernel.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 hiddev_list *list;
55 };
56
57 struct hiddev_list {
58         struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
59         int head;
60         int tail;
61         unsigned flags;
62         struct fasync_struct *fasync;
63         struct hiddev *hiddev;
64         struct hiddev_list *next;
65 };
66
67 static struct hiddev *hiddev_table[HIDDEV_MINORS];
68
69 /*
70  * Find a report, given the report's type and ID.  The ID can be specified
71  * indirectly by REPORT_ID_FIRST (which returns the first report of the given
72  * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
73  * given type which follows old_id.
74  */
75 static struct hid_report *
76 hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
77 {
78         unsigned flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
79         struct hid_report_enum *report_enum;
80         struct list_head *list;
81
82         if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
83             rinfo->report_type > HID_REPORT_TYPE_MAX) return NULL;
84
85         report_enum = hid->report_enum +
86                 (rinfo->report_type - HID_REPORT_TYPE_MIN);
87
88         switch (flags) {
89         case 0: /* Nothing to do -- report_id is already set correctly */
90                 break;
91
92         case HID_REPORT_ID_FIRST:
93                 list = report_enum->report_list.next;
94                 if (list == &report_enum->report_list)
95                         return NULL;
96                 rinfo->report_id = ((struct hid_report *) list)->id;
97                 break;
98
99         case HID_REPORT_ID_NEXT:
100                 list = (struct list_head *)
101                         report_enum->report_id_hash[rinfo->report_id & HID_REPORT_ID_MASK];
102                 if (list == NULL)
103                         return NULL;
104                 list = list->next;
105                 if (list == &report_enum->report_list)
106                         return NULL;
107                 rinfo->report_id = ((struct hid_report *) list)->id;
108                 break;
109
110         default:
111                 return NULL;
112         }
113
114         return report_enum->report_id_hash[rinfo->report_id];
115 }
116
117 /*
118  * Perform an exhaustive search of the report table for a usage, given its
119  * type and usage id.
120  */
121 static struct hid_field *
122 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
123 {
124         int i, j;
125         struct hid_report *report;
126         struct hid_report_enum *report_enum;
127         struct hid_field *field;
128
129         if (uref->report_type < HID_REPORT_TYPE_MIN ||
130             uref->report_type > HID_REPORT_TYPE_MAX) return NULL;
131
132         report_enum = hid->report_enum +
133                 (uref->report_type - HID_REPORT_TYPE_MIN);
134
135         list_for_each_entry(report, &report_enum->report_list, list)
136                 for (i = 0; i < report->maxfield; i++) {
137                         field = report->field[i];
138                         for (j = 0; j < field->maxusage; j++) {
139                                 if (field->usage[j].hid == uref->usage_code) {
140                                         uref->report_id = report->id;
141                                         uref->field_index = i;
142                                         uref->usage_index = j;
143                                         return field;
144                                 }
145                         }
146                 }
147
148         return NULL;
149 }
150
151 static void hiddev_send_event(struct hid_device *hid,
152                               struct hiddev_usage_ref *uref)
153 {
154         struct hiddev *hiddev = hid->hiddev;
155         struct hiddev_list *list = hiddev->list;
156
157         while (list) {
158                 if (uref->field_index != HID_FIELD_INDEX_NONE ||
159                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
160                         list->buffer[list->head] = *uref;
161                         list->head = (list->head + 1) &
162                                 (HIDDEV_BUFFER_SIZE - 1);
163                         kill_fasync(&list->fasync, SIGIO, POLL_IN);
164                 }
165
166                 list = list->next;
167         }
168
169         wake_up_interruptible(&hiddev->wait);
170 }
171
172 /*
173  * This is where hid.c calls into hiddev to pass an event that occurred over
174  * the interrupt pipe
175  */
176 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
177                       struct hid_usage *usage, __s32 value, struct pt_regs *regs)
178 {
179         unsigned type = field->report_type;
180         struct hiddev_usage_ref uref;
181
182         uref.report_type =
183           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
184           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
185            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE:0));
186         uref.report_id = field->report->id;
187         uref.field_index = field->index;
188         uref.usage_index = (usage - field->usage);
189         uref.usage_code = usage->hid;
190         uref.value = value;
191
192         hiddev_send_event(hid, &uref);
193 }
194
195
196 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
197 {
198         unsigned type = report->type;
199         struct hiddev_usage_ref uref;
200
201         memset(&uref, 0, sizeof(uref));
202         uref.report_type =
203           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
204           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
205            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE:0));
206         uref.report_id = report->id;
207         uref.field_index = HID_FIELD_INDEX_NONE;
208
209         hiddev_send_event(hid, &uref);
210 }
211 /*
212  * fasync file op
213  */
214 static int hiddev_fasync(int fd, struct file *file, int on)
215 {
216         int retval;
217         struct hiddev_list *list = file->private_data;
218         retval = fasync_helper(fd, file, on, &list->fasync);
219         return retval < 0 ? retval : 0;
220 }
221
222
223 /*
224  * release file op
225  */
226 static int hiddev_release(struct inode * inode, struct file * file)
227 {
228         struct hiddev_list *list = file->private_data;
229         struct hiddev_list **listptr;
230
231         listptr = &list->hiddev->list;
232         hiddev_fasync(-1, file, 0);
233
234         while (*listptr && (*listptr != list))
235                 listptr = &((*listptr)->next);
236         *listptr = (*listptr)->next;
237
238         if (!--list->hiddev->open) {
239                 if (list->hiddev->exist)
240                         hid_close(list->hiddev->hid);
241                 else
242                         kfree(list->hiddev);
243         }
244
245         kfree(list);
246
247         return 0;
248 }
249
250 /*
251  * open file op
252  */
253 static int hiddev_open(struct inode * inode, struct file * file) {
254         struct hiddev_list *list;
255
256         int i = iminor(inode) - HIDDEV_MINOR_BASE;
257
258         if (i >= HIDDEV_MINORS || !hiddev_table[i])
259                 return -ENODEV;
260
261         if (!(list = kmalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
262                 return -ENOMEM;
263         memset(list, 0, sizeof(struct hiddev_list));
264
265         list->hiddev = hiddev_table[i];
266         list->next = hiddev_table[i]->list;
267         hiddev_table[i]->list = list;
268
269         file->private_data = list;
270
271         if (!list->hiddev->open++)
272                 if (list->hiddev->exist)
273                         hid_open(hiddev_table[i]->hid);
274
275         return 0;
276 }
277
278 /*
279  * "write" file op
280  */
281 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
282 {
283         return -EINVAL;
284 }
285
286 /*
287  * "read" file op
288  */
289 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
290 {
291         DECLARE_WAITQUEUE(wait, current);
292         struct hiddev_list *list = file->private_data;
293         int event_size;
294         int retval = 0;
295
296         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
297                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
298
299         if (count < event_size)
300                 return 0;
301
302         while (retval == 0) {
303                 if (list->head == list->tail) {
304                         add_wait_queue(&list->hiddev->wait, &wait);
305                         set_current_state(TASK_INTERRUPTIBLE);
306
307                         while (list->head == list->tail) {
308                                 if (file->f_flags & O_NONBLOCK) {
309                                         retval = -EAGAIN;
310                                         break;
311                                 }
312                                 if (signal_pending(current)) {
313                                         retval = -ERESTARTSYS;
314                                         break;
315                                 }
316                                 if (!list->hiddev->exist) {
317                                         retval = -EIO;
318                                         break;
319                                 }
320
321                                 schedule();
322                         }
323
324                         set_current_state(TASK_RUNNING);
325                         remove_wait_queue(&list->hiddev->wait, &wait);
326                 }
327
328                 if (retval)
329                         return retval;
330
331
332                 while (list->head != list->tail &&
333                        retval + event_size <= count) {
334                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
335                                 if (list->buffer[list->tail].field_index !=
336                                     HID_FIELD_INDEX_NONE) {
337                                         struct hiddev_event event;
338                                         event.hid = list->buffer[list->tail].usage_code;
339                                         event.value = list->buffer[list->tail].value;
340                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event)))
341                                                 return -EFAULT;
342                                         retval += sizeof(struct hiddev_event);
343                                 }
344                         } else {
345                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
346                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
347                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref)))
348                                                 return -EFAULT;
349                                         retval += sizeof(struct hiddev_usage_ref);
350                                 }
351                         }
352                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
353                 }
354
355         }
356
357         return retval;
358 }
359
360 /*
361  * "poll" file op
362  * No kernel lock - fine
363  */
364 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
365 {
366         struct hiddev_list *list = file->private_data;
367         poll_wait(file, &list->hiddev->wait, wait);
368         if (list->head != list->tail)
369                 return POLLIN | POLLRDNORM;
370         if (!list->hiddev->exist)
371                 return POLLERR | POLLHUP;
372         return 0;
373 }
374
375 /*
376  * "ioctl" file op
377  */
378 static int hiddev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
379 {
380         struct hiddev_list *list = file->private_data;
381         struct hiddev *hiddev = list->hiddev;
382         struct hid_device *hid = hiddev->hid;
383         struct usb_device *dev = hid->dev;
384         struct hiddev_collection_info cinfo;
385         struct hiddev_report_info rinfo;
386         struct hiddev_field_info finfo;
387         struct hiddev_usage_ref_multi *uref_multi=NULL;
388         struct hiddev_usage_ref *uref;
389         struct hiddev_devinfo dinfo;
390         struct hid_report *report;
391         struct hid_field *field;
392         void __user *user_arg = (void __user *)arg;
393         int i;
394
395         if (!hiddev->exist)
396                 return -EIO;
397
398         switch (cmd) {
399
400         case HIDIOCGVERSION:
401                 return put_user(HID_VERSION, (int __user *)arg);
402
403         case HIDIOCAPPLICATION:
404                 if (arg < 0 || arg >= hid->maxapplication)
405                         return -EINVAL;
406
407                 for (i = 0; i < hid->maxcollection; i++)
408                         if (hid->collection[i].type ==
409                             HID_COLLECTION_APPLICATION && arg-- == 0)
410                                 break;
411
412                 if (i == hid->maxcollection)
413                         return -EINVAL;
414
415                 return hid->collection[i].usage;
416
417         case HIDIOCGDEVINFO:
418                 dinfo.bustype = BUS_USB;
419                 dinfo.busnum = dev->bus->busnum;
420                 dinfo.devnum = dev->devnum;
421                 dinfo.ifnum = hid->ifnum;
422                 dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
423                 dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
424                 dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
425                 dinfo.num_applications = hid->maxapplication;
426                 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
427                         return -EFAULT;
428
429                 return 0;
430
431         case HIDIOCGFLAG:
432                 if (put_user(list->flags, (int __user *)arg))
433                         return -EFAULT;
434
435                 return 0;
436
437         case HIDIOCSFLAG:
438                 {
439                         int newflags;
440                         if (get_user(newflags, (int __user *)arg))
441                                 return -EFAULT;
442
443                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
444                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
445                              (newflags & HIDDEV_FLAG_UREF) == 0))
446                                 return -EINVAL;
447
448                         list->flags = newflags;
449
450                         return 0;
451                 }
452
453         case HIDIOCGSTRING:
454                 {
455                         int idx, len;
456                         char *buf;
457
458                         if (get_user(idx, (int __user *)arg))
459                                 return -EFAULT;
460
461                         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
462                                 return -ENOMEM;
463
464                         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
465                                 kfree(buf);
466                                 return -EINVAL;
467                         }
468
469                         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
470                                 kfree(buf);
471                                 return -EFAULT;
472                         }
473
474                         kfree(buf);
475
476                         return len;
477                 }
478
479         case HIDIOCINITREPORT:
480                 hid_init_reports(hid);
481
482                 return 0;
483
484         case HIDIOCGREPORT:
485                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
486                         return -EFAULT;
487
488                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
489                         return -EINVAL;
490
491                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
492                         return -EINVAL;
493
494                 hid_submit_report(hid, report, USB_DIR_IN);
495                 hid_wait_io(hid);
496
497                 return 0;
498
499         case HIDIOCSREPORT:
500                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
501                         return -EFAULT;
502
503                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
504                         return -EINVAL;
505
506                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
507                         return -EINVAL;
508
509                 hid_submit_report(hid, report, USB_DIR_OUT);
510                 hid_wait_io(hid);
511
512                 return 0;
513
514         case HIDIOCGREPORTINFO:
515                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
516                         return -EFAULT;
517
518                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
519                         return -EINVAL;
520
521                 rinfo.num_fields = report->maxfield;
522
523                 if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
524                         return -EFAULT;
525
526                 return 0;
527
528         case HIDIOCGFIELDINFO:
529                 if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
530                         return -EFAULT;
531                 rinfo.report_type = finfo.report_type;
532                 rinfo.report_id = finfo.report_id;
533                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
534                         return -EINVAL;
535
536                 if (finfo.field_index >= report->maxfield)
537                         return -EINVAL;
538
539                 field = report->field[finfo.field_index];
540                 memset(&finfo, 0, sizeof(finfo));
541                 finfo.report_type = rinfo.report_type;
542                 finfo.report_id = rinfo.report_id;
543                 finfo.field_index = field->report_count - 1;
544                 finfo.maxusage = field->maxusage;
545                 finfo.flags = field->flags;
546                 finfo.physical = field->physical;
547                 finfo.logical = field->logical;
548                 finfo.application = field->application;
549                 finfo.logical_minimum = field->logical_minimum;
550                 finfo.logical_maximum = field->logical_maximum;
551                 finfo.physical_minimum = field->physical_minimum;
552                 finfo.physical_maximum = field->physical_maximum;
553                 finfo.unit_exponent = field->unit_exponent;
554                 finfo.unit = field->unit;
555
556                 if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
557                         return -EFAULT;
558
559                 return 0;
560
561         case HIDIOCGUCODE:
562                 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
563                 if (!uref_multi)
564                         return -ENOMEM;
565                 uref = &uref_multi->uref;
566                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
567                         goto fault;
568
569                 rinfo.report_type = uref->report_type;
570                 rinfo.report_id = uref->report_id;
571                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
572                         goto inval;
573
574                 if (uref->field_index >= report->maxfield)
575                         goto inval;
576
577                 field = report->field[uref->field_index];
578                 if (uref->usage_index >= field->maxusage)
579                         goto inval;
580
581                 uref->usage_code = field->usage[uref->usage_index].hid;
582
583                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
584                         goto fault;
585
586                 kfree(uref_multi);
587                 return 0;
588
589         case HIDIOCGUSAGE:
590         case HIDIOCSUSAGE:
591         case HIDIOCGUSAGES:
592         case HIDIOCSUSAGES:
593         case HIDIOCGCOLLECTIONINDEX:
594                 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
595                 if (!uref_multi)
596                         return -ENOMEM;
597                 uref = &uref_multi->uref;
598                 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
599                         if (copy_from_user(uref_multi, user_arg,
600                                            sizeof(*uref_multi)))
601                                 goto fault;
602                 } else {
603                         if (copy_from_user(uref, user_arg, sizeof(*uref)))
604                                 goto fault;
605                 }
606
607                 if (cmd != HIDIOCGUSAGE &&
608                     cmd != HIDIOCGUSAGES &&
609                     uref->report_type == HID_REPORT_TYPE_INPUT)
610                         goto inval;
611
612                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
613                         field = hiddev_lookup_usage(hid, uref);
614                         if (field == NULL)
615                                 goto inval;
616                 } else {
617                         rinfo.report_type = uref->report_type;
618                         rinfo.report_id = uref->report_id;
619                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
620                                 goto inval;
621
622                         if (uref->field_index >= report->maxfield)
623                                 goto inval;
624
625                         field = report->field[uref->field_index];
626
627                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
628                                 if (uref->usage_index >= field->maxusage)
629                                         goto inval;
630                         } else if (uref->usage_index >= field->report_count)
631                                 goto inval;
632
633                         else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
634                                  (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
635                                   uref->usage_index + uref_multi->num_values >= field->report_count))
636                                 goto inval;
637                         }
638
639                 switch (cmd) {
640                         case HIDIOCGUSAGE:
641                                 uref->value = field->value[uref->usage_index];
642                                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
643                                         goto fault;
644                                 goto goodreturn;
645
646                         case HIDIOCSUSAGE:
647                                 field->value[uref->usage_index] = uref->value;
648                                 goto goodreturn;
649
650                         case HIDIOCGCOLLECTIONINDEX:
651                                 kfree(uref_multi);
652                                 return field->usage[uref->usage_index].collection_index;
653                         case HIDIOCGUSAGES:
654                                 for (i = 0; i < uref_multi->num_values; i++)
655                                         uref_multi->values[i] =
656                                             field->value[uref->usage_index + i];
657                                 if (copy_to_user(user_arg, uref_multi,
658                                                  sizeof(*uref_multi)))
659                                         goto fault;
660                                 goto goodreturn;
661                         case HIDIOCSUSAGES:
662                                 for (i = 0; i < uref_multi->num_values; i++)
663                                         field->value[uref->usage_index + i] =
664                                             uref_multi->values[i];
665                                 goto goodreturn;
666                 }
667
668 goodreturn:
669                 kfree(uref_multi);
670                 return 0;
671 fault:
672                 kfree(uref_multi);
673                 return -EFAULT;
674 inval:
675                 kfree(uref_multi);
676                 return -EINVAL;
677
678         case HIDIOCGCOLLECTIONINFO:
679                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
680                         return -EFAULT;
681
682                 if (cinfo.index >= hid->maxcollection)
683                         return -EINVAL;
684
685                 cinfo.type = hid->collection[cinfo.index].type;
686                 cinfo.usage = hid->collection[cinfo.index].usage;
687                 cinfo.level = hid->collection[cinfo.index].level;
688
689                 if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
690                         return -EFAULT;
691                 return 0;
692
693         default:
694
695                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
696                         return -EINVAL;
697
698                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
699                         int len;
700                         if (!hid->name)
701                                 return 0;
702                         len = strlen(hid->name) + 1;
703                         if (len > _IOC_SIZE(cmd))
704                                  len = _IOC_SIZE(cmd);
705                         return copy_to_user(user_arg, hid->name, len) ?
706                                 -EFAULT : len;
707                 }
708
709                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
710                         int len;
711                         if (!hid->phys)
712                                 return 0;
713                         len = strlen(hid->phys) + 1;
714                         if (len > _IOC_SIZE(cmd))
715                                 len = _IOC_SIZE(cmd);
716                         return copy_to_user(user_arg, hid->phys, len) ?
717                                 -EFAULT : len;
718                 }
719         }
720         return -EINVAL;
721 }
722
723 static struct file_operations hiddev_fops = {
724         .owner =        THIS_MODULE,
725         .read =         hiddev_read,
726         .write =        hiddev_write,
727         .poll =         hiddev_poll,
728         .open =         hiddev_open,
729         .release =      hiddev_release,
730         .ioctl =        hiddev_ioctl,
731         .fasync =       hiddev_fasync,
732 };
733
734 static struct usb_class_driver hiddev_class = {
735         .name =         "hiddev%d",
736         .fops =         &hiddev_fops,
737         .minor_base =   HIDDEV_MINOR_BASE,
738 };
739
740 /*
741  * This is where hid.c calls us to connect a hid device to the hiddev driver
742  */
743 int hiddev_connect(struct hid_device *hid)
744 {
745         struct hiddev *hiddev;
746         int i;
747         int retval;
748
749         for (i = 0; i < hid->maxcollection; i++)
750                 if (hid->collection[i].type ==
751                     HID_COLLECTION_APPLICATION &&
752                     !IS_INPUT_APPLICATION(hid->collection[i].usage))
753                         break;
754
755         if (i == hid->maxcollection && (hid->quirks & HID_QUIRK_HIDDEV) == 0)
756                 return -1;
757
758         if (!(hiddev = kmalloc(sizeof(struct hiddev), GFP_KERNEL)))
759                 return -1;
760         memset(hiddev, 0, sizeof(struct hiddev));
761
762         retval = usb_register_dev(hid->intf, &hiddev_class);
763         if (retval) {
764                 err("Not able to get a minor for this device.");
765                 kfree(hiddev);
766                 return -1;
767         }
768
769         init_waitqueue_head(&hiddev->wait);
770
771         hiddev_table[hid->intf->minor - HIDDEV_MINOR_BASE] = hiddev;
772
773         hiddev->hid = hid;
774         hiddev->exist = 1;
775
776         hid->minor = hid->intf->minor;
777         hid->hiddev = hiddev;
778
779         return 0;
780 }
781
782 /*
783  * This is where hid.c calls us to disconnect a hiddev device from the
784  * corresponding hid device (usually because the usb device has disconnected)
785  */
786 static struct usb_class_driver hiddev_class;
787 void hiddev_disconnect(struct hid_device *hid)
788 {
789         struct hiddev *hiddev = hid->hiddev;
790
791         hiddev->exist = 0;
792
793         hiddev_table[hiddev->hid->minor - HIDDEV_MINOR_BASE] = NULL;
794         usb_deregister_dev(hiddev->hid->intf, &hiddev_class);
795
796         if (hiddev->open) {
797                 hid_close(hiddev->hid);
798                 wake_up_interruptible(&hiddev->wait);
799         } else {
800                 kfree(hiddev);
801         }
802 }
803
804 /* Currently this driver is a USB driver.  It's not a conventional one in
805  * the sense that it doesn't probe at the USB level.  Instead it waits to
806  * be connected by HID through the hiddev_connect / hiddev_disconnect
807  * routines.  The reason to register as a USB device is to gain part of the
808  * minor number space from the USB major.
809  *
810  * In theory, should the HID code be generalized to more than one physical
811  * medium (say, IEEE 1384), this driver will probably need to register its
812  * own major number, and in doing so, no longer need to register with USB.
813  * At that point the probe routine and hiddev_driver struct below will no
814  * longer be useful.
815  */
816
817
818 /* We never attach in this manner, and rely on HID to connect us.  This
819  * is why there is no disconnect routine defined in the usb_driver either.
820  */
821 static int hiddev_usbd_probe(struct usb_interface *intf,
822                              const struct usb_device_id *hiddev_info)
823 {
824         return -ENODEV;
825 }
826
827
828 static /* const */ struct usb_driver hiddev_driver = {
829         .name =         "hiddev",
830         .probe =        hiddev_usbd_probe,
831 };
832
833 int __init hiddev_init(void)
834 {
835         devfs_mk_dir("usb/hid");
836         return usb_register(&hiddev_driver);
837 }
838
839 void hiddev_exit(void)
840 {
841         usb_deregister(&hiddev_driver);
842         devfs_remove("usb/hid");
843 }