Merge branch 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl
[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      2048
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 usb_driver hiddev_driver;
71
72 /*
73  * Find a report, given the report's type and ID.  The ID can be specified
74  * indirectly by REPORT_ID_FIRST (which returns the first report of the given
75  * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
76  * given type which follows old_id.
77  */
78 static struct hid_report *
79 hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
80 {
81         unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
82         unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK;
83         struct hid_report_enum *report_enum;
84         struct hid_report *report;
85         struct list_head *list;
86
87         if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
88             rinfo->report_type > HID_REPORT_TYPE_MAX)
89                 return NULL;
90
91         report_enum = hid->report_enum +
92                 (rinfo->report_type - HID_REPORT_TYPE_MIN);
93
94         switch (flags) {
95         case 0: /* Nothing to do -- report_id is already set correctly */
96                 break;
97
98         case HID_REPORT_ID_FIRST:
99                 if (list_empty(&report_enum->report_list))
100                         return NULL;
101
102                 list = report_enum->report_list.next;
103                 report = list_entry(list, struct hid_report, list);
104                 rinfo->report_id = report->id;
105                 break;
106
107         case HID_REPORT_ID_NEXT:
108                 report = report_enum->report_id_hash[rid];
109                 if (!report)
110                         return NULL;
111
112                 list = report->list.next;
113                 if (list == &report_enum->report_list)
114                         return NULL;
115
116                 report = list_entry(list, struct hid_report, list);
117                 rinfo->report_id = report->id;
118                 break;
119
120         default:
121                 return NULL;
122         }
123
124         return report_enum->report_id_hash[rinfo->report_id];
125 }
126
127 /*
128  * Perform an exhaustive search of the report table for a usage, given its
129  * type and usage id.
130  */
131 static struct hid_field *
132 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
133 {
134         int i, j;
135         struct hid_report *report;
136         struct hid_report_enum *report_enum;
137         struct hid_field *field;
138
139         if (uref->report_type < HID_REPORT_TYPE_MIN ||
140             uref->report_type > HID_REPORT_TYPE_MAX)
141                 return NULL;
142
143         report_enum = hid->report_enum +
144                 (uref->report_type - HID_REPORT_TYPE_MIN);
145
146         list_for_each_entry(report, &report_enum->report_list, list) {
147                 for (i = 0; i < report->maxfield; i++) {
148                         field = report->field[i];
149                         for (j = 0; j < field->maxusage; j++) {
150                                 if (field->usage[j].hid == uref->usage_code) {
151                                         uref->report_id = report->id;
152                                         uref->field_index = i;
153                                         uref->usage_index = j;
154                                         return field;
155                                 }
156                         }
157                 }
158         }
159
160         return NULL;
161 }
162
163 static void hiddev_send_event(struct hid_device *hid,
164                               struct hiddev_usage_ref *uref)
165 {
166         struct hiddev *hiddev = hid->hiddev;
167         struct hiddev_list *list;
168         unsigned long flags;
169
170         spin_lock_irqsave(&hiddev->list_lock, flags);
171         list_for_each_entry(list, &hiddev->list, node) {
172                 if (uref->field_index != HID_FIELD_INDEX_NONE ||
173                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
174                         list->buffer[list->head] = *uref;
175                         list->head = (list->head + 1) &
176                                 (HIDDEV_BUFFER_SIZE - 1);
177                         kill_fasync(&list->fasync, SIGIO, POLL_IN);
178                 }
179         }
180         spin_unlock_irqrestore(&hiddev->list_lock, flags);
181
182         wake_up_interruptible(&hiddev->wait);
183 }
184
185 /*
186  * This is where hid.c calls into hiddev to pass an event that occurred over
187  * the interrupt pipe
188  */
189 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
190                       struct hid_usage *usage, __s32 value)
191 {
192         unsigned type = field->report_type;
193         struct hiddev_usage_ref uref;
194
195         uref.report_type =
196           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
197           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
198            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
199         uref.report_id = field->report->id;
200         uref.field_index = field->index;
201         uref.usage_index = (usage - field->usage);
202         uref.usage_code = usage->hid;
203         uref.value = value;
204
205         hiddev_send_event(hid, &uref);
206 }
207 EXPORT_SYMBOL_GPL(hiddev_hid_event);
208
209 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
210 {
211         unsigned type = report->type;
212         struct hiddev_usage_ref uref;
213
214         memset(&uref, 0, sizeof(uref));
215         uref.report_type =
216           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
217           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
218            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
219         uref.report_id = report->id;
220         uref.field_index = HID_FIELD_INDEX_NONE;
221
222         hiddev_send_event(hid, &uref);
223 }
224
225 /*
226  * fasync file op
227  */
228 static int hiddev_fasync(int fd, struct file *file, int on)
229 {
230         struct hiddev_list *list = file->private_data;
231
232         return fasync_helper(fd, file, on, &list->fasync);
233 }
234
235
236 /*
237  * release file op
238  */
239 static int hiddev_release(struct inode * inode, struct file * file)
240 {
241         struct hiddev_list *list = file->private_data;
242         unsigned long flags;
243
244         spin_lock_irqsave(&list->hiddev->list_lock, flags);
245         list_del(&list->node);
246         spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
247
248         if (!--list->hiddev->open) {
249                 if (list->hiddev->exist) {
250                         usbhid_close(list->hiddev->hid);
251                         usbhid_put_power(list->hiddev->hid);
252                 } else {
253                         kfree(list->hiddev);
254                 }
255         }
256
257         kfree(list);
258
259         return 0;
260 }
261
262 /*
263  * open file op
264  */
265 static int hiddev_open(struct inode *inode, struct file *file)
266 {
267         struct hiddev_list *list;
268         struct usb_interface *intf;
269         struct hid_device *hid;
270         struct hiddev *hiddev;
271         int res;
272
273         intf = usbhid_find_interface(iminor(inode));
274         if (!intf)
275                 return -ENODEV;
276         hid = usb_get_intfdata(intf);
277         hiddev = hid->hiddev;
278
279         if (!(list = kzalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
280                 return -ENOMEM;
281         mutex_init(&list->thread_lock);
282         list->hiddev = hiddev;
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->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->list);
304         spin_unlock_irq(&list->hiddev->list_lock);
305
306         if (!list->hiddev->open++)
307                 if (list->hiddev->exist) {
308                         struct hid_device *hid = hiddev->hid;
309                         res = usbhid_get_power(hid);
310                         if (res < 0) {
311                                 res = -EIO;
312                                 goto bail;
313                         }
314                         usbhid_open(hid);
315                 }
316         return 0;
317 bail:
318         file->private_data = NULL;
319         kfree(list);
320         return res;
321 }
322
323 /*
324  * "write" file op
325  */
326 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
327 {
328         return -EINVAL;
329 }
330
331 /*
332  * "read" file op
333  */
334 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
335 {
336         DEFINE_WAIT(wait);
337         struct hiddev_list *list = file->private_data;
338         int event_size;
339         int retval;
340
341         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
342                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
343
344         if (count < event_size)
345                 return 0;
346
347         /* lock against other threads */
348         retval = mutex_lock_interruptible(&list->thread_lock);
349         if (retval)
350                 return -ERESTARTSYS;
351
352         while (retval == 0) {
353                 if (list->head == list->tail) {
354                         prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);
355
356                         while (list->head == list->tail) {
357                                 if (file->f_flags & O_NONBLOCK) {
358                                         retval = -EAGAIN;
359                                         break;
360                                 }
361                                 if (signal_pending(current)) {
362                                         retval = -ERESTARTSYS;
363                                         break;
364                                 }
365                                 if (!list->hiddev->exist) {
366                                         retval = -EIO;
367                                         break;
368                                 }
369
370                                 /* let O_NONBLOCK tasks run */
371                                 mutex_unlock(&list->thread_lock);
372                                 schedule();
373                                 if (mutex_lock_interruptible(&list->thread_lock))
374                                         return -EINTR;
375                                 set_current_state(TASK_INTERRUPTIBLE);
376                         }
377                         finish_wait(&list->hiddev->wait, &wait);
378
379                 }
380
381                 if (retval) {
382                         mutex_unlock(&list->thread_lock);
383                         return retval;
384                 }
385
386
387                 while (list->head != list->tail &&
388                        retval + event_size <= count) {
389                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
390                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
391                                         struct hiddev_event event;
392
393                                         event.hid = list->buffer[list->tail].usage_code;
394                                         event.value = list->buffer[list->tail].value;
395                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {
396                                                 mutex_unlock(&list->thread_lock);
397                                                 return -EFAULT;
398                                         }
399                                         retval += sizeof(struct hiddev_event);
400                                 }
401                         } else {
402                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
403                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
404
405                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {
406                                                 mutex_unlock(&list->thread_lock);
407                                                 return -EFAULT;
408                                         }
409                                         retval += sizeof(struct hiddev_usage_ref);
410                                 }
411                         }
412                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
413                 }
414
415         }
416         mutex_unlock(&list->thread_lock);
417
418         return retval;
419 }
420
421 /*
422  * "poll" file op
423  * No kernel lock - fine
424  */
425 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
426 {
427         struct hiddev_list *list = file->private_data;
428
429         poll_wait(file, &list->hiddev->wait, wait);
430         if (list->head != list->tail)
431                 return POLLIN | POLLRDNORM;
432         if (!list->hiddev->exist)
433                 return POLLERR | POLLHUP;
434         return 0;
435 }
436
437 /*
438  * "ioctl" file op
439  */
440 static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
441 {
442         struct hid_device *hid = hiddev->hid;
443         struct hiddev_report_info rinfo;
444         struct hiddev_usage_ref_multi *uref_multi = NULL;
445         struct hiddev_usage_ref *uref;
446         struct hid_report *report;
447         struct hid_field *field;
448         int i;
449
450         uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
451         if (!uref_multi)
452                 return -ENOMEM;
453         uref = &uref_multi->uref;
454         if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
455                 if (copy_from_user(uref_multi, user_arg,
456                                    sizeof(*uref_multi)))
457                         goto fault;
458         } else {
459                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
460                         goto fault;
461         }
462
463         switch (cmd) {
464         case HIDIOCGUCODE:
465                 rinfo.report_type = uref->report_type;
466                 rinfo.report_id = uref->report_id;
467                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
468                         goto inval;
469
470                 if (uref->field_index >= report->maxfield)
471                         goto inval;
472
473                 field = report->field[uref->field_index];
474                 if (uref->usage_index >= field->maxusage)
475                         goto inval;
476
477                 uref->usage_code = field->usage[uref->usage_index].hid;
478
479                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
480                         goto fault;
481
482                 goto goodreturn;
483
484         default:
485                 if (cmd != HIDIOCGUSAGE &&
486                     cmd != HIDIOCGUSAGES &&
487                     uref->report_type == HID_REPORT_TYPE_INPUT)
488                         goto inval;
489
490                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
491                         field = hiddev_lookup_usage(hid, uref);
492                         if (field == NULL)
493                                 goto inval;
494                 } else {
495                         rinfo.report_type = uref->report_type;
496                         rinfo.report_id = uref->report_id;
497                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
498                                 goto inval;
499
500                         if (uref->field_index >= report->maxfield)
501                                 goto inval;
502
503                         field = report->field[uref->field_index];
504
505                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
506                                 if (uref->usage_index >= field->maxusage)
507                                         goto inval;
508                         } else if (uref->usage_index >= field->report_count)
509                                 goto inval;
510
511                         else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
512                                  (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
513                                   uref->usage_index + uref_multi->num_values > field->report_count))
514                                 goto inval;
515                         }
516
517                 switch (cmd) {
518                 case HIDIOCGUSAGE:
519                         uref->value = field->value[uref->usage_index];
520                         if (copy_to_user(user_arg, uref, sizeof(*uref)))
521                                 goto fault;
522                         goto goodreturn;
523
524                 case HIDIOCSUSAGE:
525                         field->value[uref->usage_index] = uref->value;
526                         goto goodreturn;
527
528                 case HIDIOCGCOLLECTIONINDEX:
529                         i = field->usage[uref->usage_index].collection_index;
530                         kfree(uref_multi);
531                         return i;
532                 case HIDIOCGUSAGES:
533                         for (i = 0; i < uref_multi->num_values; i++)
534                                 uref_multi->values[i] =
535                                     field->value[uref->usage_index + i];
536                         if (copy_to_user(user_arg, uref_multi,
537                                          sizeof(*uref_multi)))
538                                 goto fault;
539                         goto goodreturn;
540                 case HIDIOCSUSAGES:
541                         for (i = 0; i < uref_multi->num_values; i++)
542                                 field->value[uref->usage_index + i] =
543                                     uref_multi->values[i];
544                         goto goodreturn;
545                 }
546
547 goodreturn:
548                 kfree(uref_multi);
549                 return 0;
550 fault:
551                 kfree(uref_multi);
552                 return -EFAULT;
553 inval:
554                 kfree(uref_multi);
555                 return -EINVAL;
556         }
557 }
558
559 static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
560 {
561         struct hid_device *hid = hiddev->hid;
562         struct usb_device *dev = hid_to_usb_dev(hid);
563         int idx, len;
564         char *buf;
565
566         if (get_user(idx, (int __user *)user_arg))
567                 return -EFAULT;
568
569         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
570                 return -ENOMEM;
571
572         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
573                 kfree(buf);
574                 return -EINVAL;
575         }
576
577         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
578                 kfree(buf);
579                 return -EFAULT;
580         }
581
582         kfree(buf);
583
584         return len;
585 }
586
587 static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
588 {
589         struct hiddev_list *list = file->private_data;
590         struct hiddev *hiddev = list->hiddev;
591         struct hid_device *hid = hiddev->hid;
592         struct usb_device *dev;
593         struct hiddev_collection_info cinfo;
594         struct hiddev_report_info rinfo;
595         struct hiddev_field_info finfo;
596         struct hiddev_devinfo dinfo;
597         struct hid_report *report;
598         struct hid_field *field;
599         struct usbhid_device *usbhid = hid->driver_data;
600         void __user *user_arg = (void __user *)arg;
601         int i, r;
602         
603         /* Called without BKL by compat methods so no BKL taken */
604
605         /* FIXME: Who or what stop this racing with a disconnect ?? */
606         if (!hiddev->exist || !hid)
607                 return -EIO;
608
609         dev = hid_to_usb_dev(hid);
610
611         switch (cmd) {
612
613         case HIDIOCGVERSION:
614                 return put_user(HID_VERSION, (int __user *)arg);
615
616         case HIDIOCAPPLICATION:
617                 if (arg < 0 || arg >= hid->maxapplication)
618                         return -EINVAL;
619
620                 for (i = 0; i < hid->maxcollection; i++)
621                         if (hid->collection[i].type ==
622                             HID_COLLECTION_APPLICATION && arg-- == 0)
623                                 break;
624
625                 if (i == hid->maxcollection)
626                         return -EINVAL;
627
628                 return hid->collection[i].usage;
629
630         case HIDIOCGDEVINFO:
631                 dinfo.bustype = BUS_USB;
632                 dinfo.busnum = dev->bus->busnum;
633                 dinfo.devnum = dev->devnum;
634                 dinfo.ifnum = usbhid->ifnum;
635                 dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
636                 dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
637                 dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
638                 dinfo.num_applications = hid->maxapplication;
639                 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
640                         return -EFAULT;
641
642                 return 0;
643
644         case HIDIOCGFLAG:
645                 if (put_user(list->flags, (int __user *)arg))
646                         return -EFAULT;
647
648                 return 0;
649
650         case HIDIOCSFLAG:
651                 {
652                         int newflags;
653                         if (get_user(newflags, (int __user *)arg))
654                                 return -EFAULT;
655
656                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
657                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
658                              (newflags & HIDDEV_FLAG_UREF) == 0))
659                                 return -EINVAL;
660
661                         list->flags = newflags;
662
663                         return 0;
664                 }
665
666         case HIDIOCGSTRING:
667                 mutex_lock(&hiddev->existancelock);
668                 if (hiddev->exist)
669                         r = hiddev_ioctl_string(hiddev, cmd, user_arg);
670                 else
671                         r = -ENODEV;
672                 mutex_unlock(&hiddev->existancelock);
673                 return r;
674
675         case HIDIOCINITREPORT:
676                 mutex_lock(&hiddev->existancelock);
677                 if (!hiddev->exist) {
678                         mutex_unlock(&hiddev->existancelock);
679                         return -ENODEV;
680                 }
681                 usbhid_init_reports(hid);
682                 mutex_unlock(&hiddev->existancelock);
683
684                 return 0;
685
686         case HIDIOCGREPORT:
687                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
688                         return -EFAULT;
689
690                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
691                         return -EINVAL;
692
693                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
694                         return -EINVAL;
695
696                 mutex_lock(&hiddev->existancelock);
697                 if (hiddev->exist) {
698                         usbhid_submit_report(hid, report, USB_DIR_IN);
699                         usbhid_wait_io(hid);
700                 }
701                 mutex_unlock(&hiddev->existancelock);
702
703                 return 0;
704
705         case HIDIOCSREPORT:
706                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
707                         return -EFAULT;
708
709                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
710                         return -EINVAL;
711
712                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
713                         return -EINVAL;
714
715                 mutex_lock(&hiddev->existancelock);
716                 if (hiddev->exist) {
717                         usbhid_submit_report(hid, report, USB_DIR_OUT);
718                         usbhid_wait_io(hid);
719                 }
720                 mutex_unlock(&hiddev->existancelock);
721
722                 return 0;
723
724         case HIDIOCGREPORTINFO:
725                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
726                         return -EFAULT;
727
728                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
729                         return -EINVAL;
730
731                 rinfo.num_fields = report->maxfield;
732
733                 if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
734                         return -EFAULT;
735
736                 return 0;
737
738         case HIDIOCGFIELDINFO:
739                 if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
740                         return -EFAULT;
741                 rinfo.report_type = finfo.report_type;
742                 rinfo.report_id = finfo.report_id;
743                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
744                         return -EINVAL;
745
746                 if (finfo.field_index >= report->maxfield)
747                         return -EINVAL;
748
749                 field = report->field[finfo.field_index];
750                 memset(&finfo, 0, sizeof(finfo));
751                 finfo.report_type = rinfo.report_type;
752                 finfo.report_id = rinfo.report_id;
753                 finfo.field_index = field->report_count - 1;
754                 finfo.maxusage = field->maxusage;
755                 finfo.flags = field->flags;
756                 finfo.physical = field->physical;
757                 finfo.logical = field->logical;
758                 finfo.application = field->application;
759                 finfo.logical_minimum = field->logical_minimum;
760                 finfo.logical_maximum = field->logical_maximum;
761                 finfo.physical_minimum = field->physical_minimum;
762                 finfo.physical_maximum = field->physical_maximum;
763                 finfo.unit_exponent = field->unit_exponent;
764                 finfo.unit = field->unit;
765
766                 if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
767                         return -EFAULT;
768
769                 return 0;
770
771         case HIDIOCGUCODE:
772                 /* fall through */
773         case HIDIOCGUSAGE:
774         case HIDIOCSUSAGE:
775         case HIDIOCGUSAGES:
776         case HIDIOCSUSAGES:
777         case HIDIOCGCOLLECTIONINDEX:
778                 mutex_lock(&hiddev->existancelock);
779                 if (hiddev->exist)
780                         r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
781                 else
782                         r = -ENODEV;
783                 mutex_unlock(&hiddev->existancelock);
784                 return r;
785
786         case HIDIOCGCOLLECTIONINFO:
787                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
788                         return -EFAULT;
789
790                 if (cinfo.index >= hid->maxcollection)
791                         return -EINVAL;
792
793                 cinfo.type = hid->collection[cinfo.index].type;
794                 cinfo.usage = hid->collection[cinfo.index].usage;
795                 cinfo.level = hid->collection[cinfo.index].level;
796
797                 if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
798                         return -EFAULT;
799                 return 0;
800
801         default:
802
803                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
804                         return -EINVAL;
805
806                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
807                         int len;
808                         if (!hid->name)
809                                 return 0;
810                         len = strlen(hid->name) + 1;
811                         if (len > _IOC_SIZE(cmd))
812                                  len = _IOC_SIZE(cmd);
813                         return copy_to_user(user_arg, hid->name, len) ?
814                                 -EFAULT : len;
815                 }
816
817                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
818                         int len;
819                         if (!hid->phys)
820                                 return 0;
821                         len = strlen(hid->phys) + 1;
822                         if (len > _IOC_SIZE(cmd))
823                                 len = _IOC_SIZE(cmd);
824                         return copy_to_user(user_arg, hid->phys, len) ?
825                                 -EFAULT : len;
826                 }
827         }
828         return -EINVAL;
829 }
830
831 #ifdef CONFIG_COMPAT
832 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
833 {
834         return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
835 }
836 #endif
837
838 static const struct file_operations hiddev_fops = {
839         .owner =        THIS_MODULE,
840         .read =         hiddev_read,
841         .write =        hiddev_write,
842         .poll =         hiddev_poll,
843         .open =         hiddev_open,
844         .release =      hiddev_release,
845         .unlocked_ioctl =       hiddev_ioctl,
846         .fasync =       hiddev_fasync,
847 #ifdef CONFIG_COMPAT
848         .compat_ioctl   = hiddev_compat_ioctl,
849 #endif
850         .llseek         = noop_llseek,
851 };
852
853 static char *hiddev_devnode(struct device *dev, mode_t *mode)
854 {
855         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
856 }
857
858 static struct usb_class_driver hiddev_class = {
859         .name =         "hiddev%d",
860         .devnode =      hiddev_devnode,
861         .fops =         &hiddev_fops,
862         .minor_base =   HIDDEV_MINOR_BASE,
863 };
864
865 /*
866  * This is where hid.c calls us to connect a hid device to the hiddev driver
867  */
868 int hiddev_connect(struct hid_device *hid, unsigned int force)
869 {
870         struct hiddev *hiddev;
871         struct usbhid_device *usbhid = hid->driver_data;
872         int retval;
873
874         if (!force) {
875                 unsigned int i;
876                 for (i = 0; i < hid->maxcollection; i++)
877                         if (hid->collection[i].type ==
878                             HID_COLLECTION_APPLICATION &&
879                             !IS_INPUT_APPLICATION(hid->collection[i].usage))
880                                 break;
881
882                 if (i == hid->maxcollection)
883                         return -1;
884         }
885
886         if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
887                 return -1;
888
889         init_waitqueue_head(&hiddev->wait);
890         INIT_LIST_HEAD(&hiddev->list);
891         spin_lock_init(&hiddev->list_lock);
892         mutex_init(&hiddev->existancelock);
893         hid->hiddev = hiddev;
894         hiddev->hid = hid;
895         hiddev->exist = 1;
896         retval = usb_register_dev(usbhid->intf, &hiddev_class);
897         if (retval) {
898                 err_hid("Not able to get a minor for this device.");
899                 hid->hiddev = NULL;
900                 kfree(hiddev);
901                 return -1;
902         }
903         return 0;
904 }
905
906 /*
907  * This is where hid.c calls us to disconnect a hiddev device from the
908  * corresponding hid device (usually because the usb device has disconnected)
909  */
910 static struct usb_class_driver hiddev_class;
911 void hiddev_disconnect(struct hid_device *hid)
912 {
913         struct hiddev *hiddev = hid->hiddev;
914         struct usbhid_device *usbhid = hid->driver_data;
915
916         mutex_lock(&hiddev->existancelock);
917         hiddev->exist = 0;
918         mutex_unlock(&hiddev->existancelock);
919
920         usb_deregister_dev(usbhid->intf, &hiddev_class);
921
922         if (hiddev->open) {
923                 usbhid_close(hiddev->hid);
924                 wake_up_interruptible(&hiddev->wait);
925         } else {
926                 kfree(hiddev);
927         }
928 }
929
930 /* Currently this driver is a USB driver.  It's not a conventional one in
931  * the sense that it doesn't probe at the USB level.  Instead it waits to
932  * be connected by HID through the hiddev_connect / hiddev_disconnect
933  * routines.  The reason to register as a USB device is to gain part of the
934  * minor number space from the USB major.
935  *
936  * In theory, should the HID code be generalized to more than one physical
937  * medium (say, IEEE 1384), this driver will probably need to register its
938  * own major number, and in doing so, no longer need to register with USB.
939  * At that point the probe routine and hiddev_driver struct below will no
940  * longer be useful.
941  */
942
943
944 /* We never attach in this manner, and rely on HID to connect us.  This
945  * is why there is no disconnect routine defined in the usb_driver either.
946  */
947 static int hiddev_usbd_probe(struct usb_interface *intf,
948                              const struct usb_device_id *hiddev_info)
949 {
950         return -ENODEV;
951 }
952
953 static /* const */ struct usb_driver hiddev_driver = {
954         .name =         "hiddev",
955         .probe =        hiddev_usbd_probe,
956 };
957
958 int __init hiddev_init(void)
959 {
960         return usb_register(&hiddev_driver);
961 }
962
963 void hiddev_exit(void)
964 {
965         usb_deregister(&hiddev_driver);
966 }