HID: fix lock imbalance in hiddev
[linux-2.6.git] / drivers / hid / usbhid / hiddev.c
1 /*
2  *  Copyright (c) 2001 Paul Stewart
3  *  Copyright (c) 2001 Vojtech Pavlik
4  *
5  *  HID char devices, giving access to raw HID device events.
6  *
7  */
8
9 /*
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23  *
24  * Should you need to contact me, the author, you can do so either by
25  * e-mail - mail your message to Paul Stewart <stewart@wetlogic.net>
26  */
27
28 #include <linux/poll.h>
29 #include <linux/slab.h>
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/smp_lock.h>
33 #include <linux/input.h>
34 #include <linux/usb.h>
35 #include <linux/hid.h>
36 #include <linux/hiddev.h>
37 #include <linux/compat.h>
38 #include "usbhid.h"
39
40 #ifdef CONFIG_USB_DYNAMIC_MINORS
41 #define HIDDEV_MINOR_BASE       0
42 #define HIDDEV_MINORS           256
43 #else
44 #define HIDDEV_MINOR_BASE       96
45 #define HIDDEV_MINORS           16
46 #endif
47 #define HIDDEV_BUFFER_SIZE      64
48
49 struct hiddev {
50         int exist;
51         int open;
52         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 noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
397 {
398         struct hid_device *hid = hiddev->hid;
399         struct hiddev_report_info rinfo;
400         struct hiddev_usage_ref_multi *uref_multi = NULL;
401         struct hiddev_usage_ref *uref;
402         struct hid_report *report;
403         struct hid_field *field;
404         int i;
405
406         uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
407         if (!uref_multi)
408                 return -ENOMEM;
409         lock_kernel();
410         uref = &uref_multi->uref;
411         if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
412                 if (copy_from_user(uref_multi, user_arg,
413                                    sizeof(*uref_multi)))
414                         goto fault;
415         } else {
416                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
417                         goto fault;
418         }
419
420         switch (cmd) {
421         case HIDIOCGUCODE:
422                 rinfo.report_type = uref->report_type;
423                 rinfo.report_id = uref->report_id;
424                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
425                         goto inval;
426
427                 if (uref->field_index >= report->maxfield)
428                         goto inval;
429
430                 field = report->field[uref->field_index];
431                 if (uref->usage_index >= field->maxusage)
432                         goto inval;
433
434                 uref->usage_code = field->usage[uref->usage_index].hid;
435
436                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
437                         goto fault;
438
439                 goto goodreturn;
440
441         default:
442                 if (cmd != HIDIOCGUSAGE &&
443                     cmd != HIDIOCGUSAGES &&
444                     uref->report_type == HID_REPORT_TYPE_INPUT)
445                         goto inval;
446
447                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
448                         field = hiddev_lookup_usage(hid, uref);
449                         if (field == NULL)
450                                 goto inval;
451                 } else {
452                         rinfo.report_type = uref->report_type;
453                         rinfo.report_id = uref->report_id;
454                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
455                                 goto inval;
456
457                         if (uref->field_index >= report->maxfield)
458                                 goto inval;
459
460                         field = report->field[uref->field_index];
461
462                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
463                                 if (uref->usage_index >= field->maxusage)
464                                         goto inval;
465                         } else if (uref->usage_index >= field->report_count)
466                                 goto inval;
467
468                         else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
469                                  (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
470                                   uref->usage_index + uref_multi->num_values > field->report_count))
471                                 goto inval;
472                         }
473
474                 switch (cmd) {
475                 case HIDIOCGUSAGE:
476                         uref->value = field->value[uref->usage_index];
477                         if (copy_to_user(user_arg, uref, sizeof(*uref)))
478                                 goto fault;
479                         goto goodreturn;
480
481                 case HIDIOCSUSAGE:
482                         field->value[uref->usage_index] = uref->value;
483                         goto goodreturn;
484
485                 case HIDIOCGCOLLECTIONINDEX:
486                         kfree(uref_multi);
487                         return field->usage[uref->usage_index].collection_index;
488                 case HIDIOCGUSAGES:
489                         for (i = 0; i < uref_multi->num_values; i++)
490                                 uref_multi->values[i] =
491                                     field->value[uref->usage_index + i];
492                         if (copy_to_user(user_arg, uref_multi,
493                                          sizeof(*uref_multi)))
494                                 goto fault;
495                         goto goodreturn;
496                 case HIDIOCSUSAGES:
497                         for (i = 0; i < uref_multi->num_values; i++)
498                                 field->value[uref->usage_index + i] =
499                                     uref_multi->values[i];
500                         goto goodreturn;
501                 }
502
503 goodreturn:
504                 unlock_kernel();
505                 kfree(uref_multi);
506                 return 0;
507 fault:
508                 unlock_kernel();
509                 kfree(uref_multi);
510                 return -EFAULT;
511 inval:
512                 unlock_kernel();
513                 kfree(uref_multi);
514                 return -EINVAL;
515         }
516 }
517
518 static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
519 {
520         struct hid_device *hid = hiddev->hid;
521         struct usb_device *dev = hid_to_usb_dev(hid);
522         int idx, len;
523         char *buf;
524
525         if (get_user(idx, (int __user *)user_arg))
526                 return -EFAULT;
527
528         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
529                 return -ENOMEM;
530
531         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
532                 kfree(buf);
533                 return -EINVAL;
534         }
535
536         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
537                 kfree(buf);
538                 return -EFAULT;
539         }
540
541         kfree(buf);
542
543         return len;
544 }
545
546 static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
547 {
548         struct hiddev_list *list = file->private_data;
549         struct hiddev *hiddev = list->hiddev;
550         struct hid_device *hid = hiddev->hid;
551         struct usb_device *dev = hid_to_usb_dev(hid);
552         struct hiddev_collection_info cinfo;
553         struct hiddev_report_info rinfo;
554         struct hiddev_field_info finfo;
555         struct hiddev_devinfo dinfo;
556         struct hid_report *report;
557         struct hid_field *field;
558         struct usbhid_device *usbhid = hid->driver_data;
559         void __user *user_arg = (void __user *)arg;
560         int i;
561         
562         /* Called without BKL by compat methods so no BKL taken */
563
564         /* FIXME: Who or what stop this racing with a disconnect ?? */
565         if (!hiddev->exist)
566                 return -EIO;
567
568         switch (cmd) {
569
570         case HIDIOCGVERSION:
571                 return put_user(HID_VERSION, (int __user *)arg);
572
573         case HIDIOCAPPLICATION:
574                 if (arg < 0 || arg >= hid->maxapplication)
575                         return -EINVAL;
576
577                 for (i = 0; i < hid->maxcollection; i++)
578                         if (hid->collection[i].type ==
579                             HID_COLLECTION_APPLICATION && arg-- == 0)
580                                 break;
581
582                 if (i == hid->maxcollection)
583                         return -EINVAL;
584
585                 return hid->collection[i].usage;
586
587         case HIDIOCGDEVINFO:
588                 dinfo.bustype = BUS_USB;
589                 dinfo.busnum = dev->bus->busnum;
590                 dinfo.devnum = dev->devnum;
591                 dinfo.ifnum = usbhid->ifnum;
592                 dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
593                 dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
594                 dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
595                 dinfo.num_applications = hid->maxapplication;
596                 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
597                         return -EFAULT;
598
599                 return 0;
600
601         case HIDIOCGFLAG:
602                 if (put_user(list->flags, (int __user *)arg))
603                         return -EFAULT;
604
605                 return 0;
606
607         case HIDIOCSFLAG:
608                 {
609                         int newflags;
610                         if (get_user(newflags, (int __user *)arg))
611                                 return -EFAULT;
612
613                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
614                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
615                              (newflags & HIDDEV_FLAG_UREF) == 0))
616                                 return -EINVAL;
617
618                         list->flags = newflags;
619
620                         return 0;
621                 }
622
623         case HIDIOCGSTRING:
624                 return hiddev_ioctl_string(hiddev, cmd, user_arg);
625
626         case HIDIOCINITREPORT:
627                 usbhid_init_reports(hid);
628
629                 return 0;
630
631         case HIDIOCGREPORT:
632                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
633                         return -EFAULT;
634
635                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
636                         return -EINVAL;
637
638                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
639                         return -EINVAL;
640
641                 usbhid_submit_report(hid, report, USB_DIR_IN);
642                 usbhid_wait_io(hid);
643
644                 return 0;
645
646         case HIDIOCSREPORT:
647                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
648                         return -EFAULT;
649
650                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
651                         return -EINVAL;
652
653                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
654                         return -EINVAL;
655
656                 usbhid_submit_report(hid, report, USB_DIR_OUT);
657                 usbhid_wait_io(hid);
658
659                 return 0;
660
661         case HIDIOCGREPORTINFO:
662                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
663                         return -EFAULT;
664
665                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
666                         return -EINVAL;
667
668                 rinfo.num_fields = report->maxfield;
669
670                 if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
671                         return -EFAULT;
672
673                 return 0;
674
675         case HIDIOCGFIELDINFO:
676                 if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
677                         return -EFAULT;
678                 rinfo.report_type = finfo.report_type;
679                 rinfo.report_id = finfo.report_id;
680                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
681                         return -EINVAL;
682
683                 if (finfo.field_index >= report->maxfield)
684                         return -EINVAL;
685
686                 field = report->field[finfo.field_index];
687                 memset(&finfo, 0, sizeof(finfo));
688                 finfo.report_type = rinfo.report_type;
689                 finfo.report_id = rinfo.report_id;
690                 finfo.field_index = field->report_count - 1;
691                 finfo.maxusage = field->maxusage;
692                 finfo.flags = field->flags;
693                 finfo.physical = field->physical;
694                 finfo.logical = field->logical;
695                 finfo.application = field->application;
696                 finfo.logical_minimum = field->logical_minimum;
697                 finfo.logical_maximum = field->logical_maximum;
698                 finfo.physical_minimum = field->physical_minimum;
699                 finfo.physical_maximum = field->physical_maximum;
700                 finfo.unit_exponent = field->unit_exponent;
701                 finfo.unit = field->unit;
702
703                 if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
704                         return -EFAULT;
705
706                 return 0;
707
708         case HIDIOCGUCODE:
709                 /* fall through */
710         case HIDIOCGUSAGE:
711         case HIDIOCSUSAGE:
712         case HIDIOCGUSAGES:
713         case HIDIOCSUSAGES:
714         case HIDIOCGCOLLECTIONINDEX:
715                 return hiddev_ioctl_usage(hiddev, cmd, user_arg);
716
717         case HIDIOCGCOLLECTIONINFO:
718                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
719                         return -EFAULT;
720
721                 if (cinfo.index >= hid->maxcollection)
722                         return -EINVAL;
723
724                 cinfo.type = hid->collection[cinfo.index].type;
725                 cinfo.usage = hid->collection[cinfo.index].usage;
726                 cinfo.level = hid->collection[cinfo.index].level;
727
728                 if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
729                         return -EFAULT;
730                 return 0;
731
732         default:
733
734                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
735                         return -EINVAL;
736
737                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
738                         int len;
739                         if (!hid->name)
740                                 return 0;
741                         len = strlen(hid->name) + 1;
742                         if (len > _IOC_SIZE(cmd))
743                                  len = _IOC_SIZE(cmd);
744                         return copy_to_user(user_arg, hid->name, len) ?
745                                 -EFAULT : len;
746                 }
747
748                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
749                         int len;
750                         if (!hid->phys)
751                                 return 0;
752                         len = strlen(hid->phys) + 1;
753                         if (len > _IOC_SIZE(cmd))
754                                 len = _IOC_SIZE(cmd);
755                         return copy_to_user(user_arg, hid->phys, len) ?
756                                 -EFAULT : len;
757                 }
758         }
759         return -EINVAL;
760 }
761
762 #ifdef CONFIG_COMPAT
763 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
764 {
765         return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
766 }
767 #endif
768
769 static const struct file_operations hiddev_fops = {
770         .owner =        THIS_MODULE,
771         .read =         hiddev_read,
772         .write =        hiddev_write,
773         .poll =         hiddev_poll,
774         .open =         hiddev_open,
775         .release =      hiddev_release,
776         .unlocked_ioctl =       hiddev_ioctl,
777         .fasync =       hiddev_fasync,
778 #ifdef CONFIG_COMPAT
779         .compat_ioctl   = hiddev_compat_ioctl,
780 #endif
781 };
782
783 static struct usb_class_driver hiddev_class = {
784         .name =         "hiddev%d",
785         .fops =         &hiddev_fops,
786         .minor_base =   HIDDEV_MINOR_BASE,
787 };
788
789 /*
790  * This is where hid.c calls us to connect a hid device to the hiddev driver
791  */
792 int hiddev_connect(struct hid_device *hid, unsigned int force)
793 {
794         struct hiddev *hiddev;
795         struct usbhid_device *usbhid = hid->driver_data;
796         int retval;
797
798         if (!force) {
799                 unsigned int i;
800                 for (i = 0; i < hid->maxcollection; i++)
801                         if (hid->collection[i].type ==
802                             HID_COLLECTION_APPLICATION &&
803                             !IS_INPUT_APPLICATION(hid->collection[i].usage))
804                                 break;
805
806                 if (i == hid->maxcollection)
807                         return -1;
808         }
809
810         if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
811                 return -1;
812
813         retval = usb_register_dev(usbhid->intf, &hiddev_class);
814         if (retval) {
815                 err_hid("Not able to get a minor for this device.");
816                 kfree(hiddev);
817                 return -1;
818         }
819
820         init_waitqueue_head(&hiddev->wait);
821         INIT_LIST_HEAD(&hiddev->list);
822         spin_lock_init(&hiddev->list_lock);
823         hiddev->hid = hid;
824         hiddev->exist = 1;
825
826         hid->minor = usbhid->intf->minor;
827         hid->hiddev = hiddev;
828
829         hiddev_table[usbhid->intf->minor - HIDDEV_MINOR_BASE] = hiddev;
830
831         return 0;
832 }
833
834 /*
835  * This is where hid.c calls us to disconnect a hiddev device from the
836  * corresponding hid device (usually because the usb device has disconnected)
837  */
838 static struct usb_class_driver hiddev_class;
839 void hiddev_disconnect(struct hid_device *hid)
840 {
841         struct hiddev *hiddev = hid->hiddev;
842         struct usbhid_device *usbhid = hid->driver_data;
843
844         hiddev->exist = 0;
845
846         hiddev_table[hiddev->hid->minor - HIDDEV_MINOR_BASE] = NULL;
847         usb_deregister_dev(usbhid->intf, &hiddev_class);
848
849         if (hiddev->open) {
850                 usbhid_close(hiddev->hid);
851                 wake_up_interruptible(&hiddev->wait);
852         } else {
853                 kfree(hiddev);
854         }
855 }
856
857 /* Currently this driver is a USB driver.  It's not a conventional one in
858  * the sense that it doesn't probe at the USB level.  Instead it waits to
859  * be connected by HID through the hiddev_connect / hiddev_disconnect
860  * routines.  The reason to register as a USB device is to gain part of the
861  * minor number space from the USB major.
862  *
863  * In theory, should the HID code be generalized to more than one physical
864  * medium (say, IEEE 1384), this driver will probably need to register its
865  * own major number, and in doing so, no longer need to register with USB.
866  * At that point the probe routine and hiddev_driver struct below will no
867  * longer be useful.
868  */
869
870
871 /* We never attach in this manner, and rely on HID to connect us.  This
872  * is why there is no disconnect routine defined in the usb_driver either.
873  */
874 static int hiddev_usbd_probe(struct usb_interface *intf,
875                              const struct usb_device_id *hiddev_info)
876 {
877         return -ENODEV;
878 }
879
880
881 static /* const */ struct usb_driver hiddev_driver = {
882         .name =         "hiddev",
883         .probe =        hiddev_usbd_probe,
884 };
885
886 int __init hiddev_init(void)
887 {
888         return usb_register(&hiddev_driver);
889 }
890
891 void hiddev_exit(void)
892 {
893         usb_deregister(&hiddev_driver);
894 }