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 #define HIDDEV_MINOR_BASE 96
29 #define HIDDEV_MINORS 16
30 #define HIDDEV_BUFFER_SIZE 64
31
32 #include <linux/poll.h>
33 #include <linux/slab.h>
34 #include <linux/module.h>
35 #include <linux/init.h>
36 #include <linux/smp_lock.h>
37 #include <linux/input.h>
38 #include <linux/usb.h>
39 #include "hid.h"
40 #include <linux/hiddev.h>
41
42 struct hiddev {
43 int exist;
44 int open;
45 int minor;
46 wait_queue_head_t wait;
47 devfs_handle_t devfs;
48 struct hid_device *hid;
49 struct hiddev_list *list;
50 };
51
52 struct hiddev_list {
53 struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
54 int head;
55 int tail;
56 unsigned flags;
57 struct fasync_struct *fasync;
58 struct hiddev *hiddev;
59 struct hiddev_list *next;
60 };
61
62 static struct hiddev *hiddev_table[HIDDEV_MINORS];
63 static devfs_handle_t hiddev_devfs_handle;
64
65 /*
66 * Find a report, given the report's type and ID. The ID can be specified
67 * indirectly by REPORT_ID_FIRST (which returns the first report of the given
68 * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
69 * given type which follows old_id.
70 */
71 static struct hid_report *
hiddev_lookup_report(struct hid_device * hid,struct hiddev_report_info * rinfo)72 hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
73 {
74 unsigned flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
75 struct hid_report_enum *report_enum = NULL;
76 struct list_head *list;
77
78 if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
79 rinfo->report_type > HID_REPORT_TYPE_MAX) return NULL;
80
81 report_enum = hid->report_enum +
82 (rinfo->report_type - HID_REPORT_TYPE_MIN);
83
84 switch (flags) {
85 case 0: /* Nothing to do -- report_id is already set correctly */
86 break;
87
88 case HID_REPORT_ID_FIRST:
89 list = report_enum->report_list.next;
90 if (list == &report_enum->report_list) return NULL;
91 rinfo->report_id = ((struct hid_report *) list)->id;
92 break;
93
94 case HID_REPORT_ID_NEXT:
95 list = (struct list_head *)
96 report_enum->report_id_hash[rinfo->report_id &
97 HID_REPORT_ID_MASK];
98 if (list == NULL) return NULL;
99 list = list->next;
100 if (list == &report_enum->report_list) return NULL;
101 rinfo->report_id = ((struct hid_report *) list)->id;
102 break;
103
104 default:
105 return NULL;
106 }
107
108 return report_enum->report_id_hash[rinfo->report_id];
109 }
110
111 /*
112 * Perform an exhaustive search of the report table for a usage, given its
113 * type and usage id.
114 */
115 static struct hid_field *
hiddev_lookup_usage(struct hid_device * hid,struct hiddev_usage_ref * uref)116 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
117 {
118 int i, j;
119 struct hid_report *report;
120 struct hid_report_enum *report_enum;
121 struct list_head *list;
122 struct hid_field *field;
123
124 if (uref->report_type < HID_REPORT_TYPE_MIN ||
125 uref->report_type > HID_REPORT_TYPE_MAX) return NULL;
126
127 report_enum = hid->report_enum +
128 (uref->report_type - HID_REPORT_TYPE_MIN);
129 list = report_enum->report_list.next;
130 while (list != &report_enum->report_list) {
131 report = (struct hid_report *) list;
132 for (i = 0; i < report->maxfield; i++) {
133 field = report->field[i];
134 for (j = 0; j < field->maxusage; j++) {
135 if (field->usage[j].hid == uref->usage_code) {
136 uref->report_id = report->id;
137 uref->field_index = i;
138 uref->usage_index = j;
139 return field;
140 }
141 }
142 }
143 list = list->next;
144 }
145
146 return NULL;
147 }
148
hiddev_send_event(struct hid_device * hid,struct hiddev_usage_ref * uref)149 static void hiddev_send_event(struct hid_device *hid,
150 struct hiddev_usage_ref *uref)
151 {
152 struct hiddev *hiddev = hid->hiddev;
153 struct hiddev_list *list = hiddev->list;
154
155 while (list) {
156 if (uref->field_index != HID_FIELD_INDEX_NONE ||
157 (list->flags & HIDDEV_FLAG_REPORT) != 0) {
158 list->buffer[list->head] = *uref;
159 list->head = (list->head + 1) &
160 (HIDDEV_BUFFER_SIZE - 1);
161 kill_fasync(&list->fasync, SIGIO, POLL_IN);
162 }
163
164 list = list->next;
165 }
166
167 wake_up_interruptible(&hiddev->wait);
168 }
169
170 /*
171 * This is where hid.c calls into hiddev to pass an event that occurred over
172 * the interrupt pipe
173 */
hiddev_hid_event(struct hid_device * hid,struct hid_field * field,struct hid_usage * usage,__s32 value)174 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
175 struct hid_usage *usage, __s32 value)
176 {
177 unsigned type = field->report_type;
178 struct hiddev_usage_ref uref;
179
180 uref.report_type =
181 (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
182 ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
183 ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE:0));
184 uref.report_id = field->report->id;
185 uref.field_index = field->index;
186 uref.usage_index = (usage - field->usage);
187 uref.usage_code = usage->hid;
188 uref.value = value;
189
190 hiddev_send_event(hid, &uref);
191 }
192
193
hiddev_report_event(struct hid_device * hid,struct hid_report * report)194 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
195 {
196 unsigned type = report->type;
197 struct hiddev_usage_ref uref;
198
199 memset(&uref, 0, sizeof(uref));
200 uref.report_type =
201 (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
202 ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
203 ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE:0));
204 uref.report_id = report->id;
205 uref.field_index = HID_FIELD_INDEX_NONE;
206
207 hiddev_send_event(hid, &uref);
208 }
209
210 /*
211 * fasync file op
212 */
hiddev_fasync(int fd,struct file * file,int on)213 static int hiddev_fasync(int fd, struct file *file, int on)
214 {
215 int retval;
216 struct hiddev_list *list = file->private_data;
217 retval = fasync_helper(fd, file, on, &list->fasync);
218 return retval < 0 ? retval : 0;
219 }
220
221 /*
222 * De-allocate a hiddev structure
223 */
hiddev_cleanup(struct hiddev * hiddev)224 static void hiddev_cleanup(struct hiddev *hiddev)
225 {
226 devfs_unregister(hiddev->devfs);
227 hiddev_table[hiddev->minor] = NULL;
228 kfree(hiddev);
229 }
230
231 /*
232 * release file op
233 */
hiddev_release(struct inode * inode,struct file * file)234 static int hiddev_release(struct inode * inode, struct file * file)
235 {
236 struct hiddev_list *list = file->private_data;
237 struct hiddev_list **listptr;
238
239 listptr = &list->hiddev->list;
240 hiddev_fasync(-1, file, 0);
241
242 while (*listptr && (*listptr != list))
243 listptr = &((*listptr)->next);
244 *listptr = (*listptr)->next;
245
246 if (!--list->hiddev->open) {
247 if (list->hiddev->exist)
248 hid_close(list->hiddev->hid);
249 else
250 hiddev_cleanup(list->hiddev);
251 }
252
253 kfree(list);
254
255 return 0;
256 }
257
258 /*
259 * open file op
260 */
hiddev_open(struct inode * inode,struct file * file)261 static int hiddev_open(struct inode * inode, struct file * file) {
262 struct hiddev_list *list;
263
264 int i = MINOR(inode->i_rdev) - HIDDEV_MINOR_BASE;
265
266 if (i >= HIDDEV_MINORS || !hiddev_table[i])
267 return -ENODEV;
268
269 if (!(list = kmalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
270 return -ENOMEM;
271 memset(list, 0, sizeof(struct hiddev_list));
272
273 list->hiddev = hiddev_table[i];
274 list->next = hiddev_table[i]->list;
275 hiddev_table[i]->list = list;
276
277 file->private_data = list;
278
279 if (!list->hiddev->open++)
280 if (list->hiddev->exist)
281 hid_open(hiddev_table[i]->hid);
282
283 return 0;
284 }
285
286 /*
287 * "write" file op
288 */
hiddev_write(struct file * file,const char * buffer,size_t count,loff_t * ppos)289 static ssize_t hiddev_write(struct file * file, const char * buffer,
290 size_t count, loff_t *ppos)
291 {
292 return -EINVAL;
293 }
294
295 /*
296 * "read" file op
297 */
hiddev_read(struct file * file,char * buffer,size_t count,loff_t * ppos)298 static ssize_t hiddev_read(struct file * file, char * buffer, size_t count,
299 loff_t *ppos)
300 {
301 DECLARE_WAITQUEUE(wait, current);
302 struct hiddev_list *list = file->private_data;
303 int event_size;
304 int retval = 0;
305
306 event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
307 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
308
309 if (count < event_size) return 0;
310
311 while (retval == 0) {
312 if (list->head == list->tail) {
313 add_wait_queue(&list->hiddev->wait, &wait);
314 set_current_state(TASK_INTERRUPTIBLE);
315
316 while (list->head == list->tail) {
317 if (file->f_flags & O_NONBLOCK) {
318 retval = -EAGAIN;
319 break;
320 }
321 if (signal_pending(current)) {
322 retval = -ERESTARTSYS;
323 break;
324 }
325 if (!list->hiddev->exist) {
326 retval = -EIO;
327 break;
328 }
329
330 schedule();
331 set_current_state(TASK_INTERRUPTIBLE);
332 }
333
334 set_current_state(TASK_RUNNING);
335 remove_wait_queue(&list->hiddev->wait, &wait);
336 }
337
338 if (retval)
339 return retval;
340
341 while (list->head != list->tail &&
342 retval + event_size <= count) {
343 if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
344 if (list->buffer[list->tail].field_index !=
345 HID_FIELD_INDEX_NONE) {
346 struct hiddev_event event;
347 event.hid = list->buffer[list->tail].usage_code;
348 event.value = list->buffer[list->tail].value;
349 if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event)))
350 return -EFAULT;
351 retval += sizeof(struct hiddev_event);
352 }
353 } else {
354 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
355 (list->flags & HIDDEV_FLAG_REPORT) != 0) {
356 if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref)))
357 return -EFAULT;
358 retval += sizeof(struct hiddev_usage_ref);
359 }
360 }
361 list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
362 }
363
364 }
365
366 return retval;
367 }
368
369 /*
370 * "poll" file op
371 * No kernel lock - fine
372 */
hiddev_poll(struct file * file,poll_table * wait)373 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
374 {
375 struct hiddev_list *list = file->private_data;
376 poll_wait(file, &list->hiddev->wait, wait);
377 if (list->head != list->tail)
378 return POLLIN | POLLRDNORM;
379 if (!list->hiddev->exist)
380 return POLLERR | POLLHUP;
381 return 0;
382 }
383
384 #define GET_TIMEOUT 3
385 #define SET_TIMEOUT 3
386
387 /*
388 * "ioctl" file op
389 */
hiddev_ioctl(struct inode * inode,struct file * file,unsigned int cmd,unsigned long arg)390 static int hiddev_ioctl(struct inode *inode, struct file *file,
391 unsigned int cmd, unsigned long arg)
392 {
393 struct hiddev_list *list = file->private_data;
394 struct hiddev *hiddev = list->hiddev;
395 struct hid_device *hid = hiddev->hid;
396 struct usb_device *dev = hid->dev;
397 struct hiddev_collection_info cinfo;
398 struct hiddev_report_info rinfo;
399 struct hiddev_field_info finfo;
400 struct hiddev_usage_ref_multi uref_multi;
401 struct hiddev_usage_ref *uref = &uref_multi.uref;
402 struct hiddev_devinfo dinfo;
403 struct hid_report *report;
404 struct hid_field *field;
405 int i;
406
407 if (!hiddev->exist) return -EIO;
408
409 switch (cmd) {
410
411 case HIDIOCGVERSION:
412 return put_user(HID_VERSION, (int *) arg);
413
414 case HIDIOCAPPLICATION:
415 if (arg < 0 || arg >= hid->maxapplication)
416 return -EINVAL;
417
418 for (i = 0; i < hid->maxcollection; i++)
419 if (hid->collection[i].type ==
420 HID_COLLECTION_APPLICATION && arg-- == 0)
421 break;
422
423 if (i == hid->maxcollection)
424 return -EINVAL;
425
426 return hid->collection[i].usage;
427
428 case HIDIOCGDEVINFO:
429 dinfo.bustype = BUS_USB;
430 dinfo.busnum = dev->bus->busnum;
431 dinfo.devnum = dev->devnum;
432 dinfo.ifnum = hid->ifnum;
433 dinfo.vendor = dev->descriptor.idVendor;
434 dinfo.product = dev->descriptor.idProduct;
435 dinfo.version = dev->descriptor.bcdDevice;
436 dinfo.num_applications = hid->maxapplication;
437 if (copy_to_user((void *) arg, &dinfo, sizeof(dinfo)))
438 return -EFAULT;
439 return 0;
440
441 case HIDIOCGFLAG:
442 return put_user(list->flags, (int *) arg);
443
444 case HIDIOCSFLAG:
445 {
446 int newflags;
447 if (get_user(newflags, (int *) arg))
448 return -EFAULT;
449
450 if ((newflags & ~HIDDEV_FLAGS) != 0 ||
451 ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
452 (newflags & HIDDEV_FLAG_UREF) == 0))
453 return -EINVAL;
454
455 list->flags = newflags;
456
457 return 0;
458 }
459
460 case HIDIOCGSTRING:
461 {
462 int idx, len;
463 char *buf;
464
465 if (get_user(idx, (int *) arg))
466 return -EFAULT;
467
468 if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
469 return -ENOMEM;
470
471 if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
472 kfree(buf);
473 return -EINVAL;
474 }
475
476 if (copy_to_user((void *) (arg+sizeof(int)), buf, len+1)) {
477 kfree(buf);
478 return -EFAULT;
479 }
480
481 kfree(buf);
482
483 return len;
484 }
485
486 case HIDIOCINITREPORT:
487 hid_init_reports(hid);
488
489 return 0;
490
491 case HIDIOCGREPORT:
492 if (copy_from_user(&rinfo, (void *) arg, sizeof(rinfo)))
493 return -EFAULT;
494
495 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
496 return -EINVAL;
497
498 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
499 return -EINVAL;
500
501 hid_read_report(hid, report);
502
503 return 0;
504
505 case HIDIOCSREPORT:
506 if (copy_from_user(&rinfo, (void *) arg, sizeof(rinfo)))
507 return -EFAULT;
508
509 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
510 return -EINVAL;
511
512 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
513 return -EINVAL;
514
515 hid_write_report(hid, report);
516
517 return 0;
518
519 case HIDIOCGREPORTINFO:
520 if (copy_from_user(&rinfo, (void *) arg, sizeof(rinfo)))
521 return -EFAULT;
522
523 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
524 return -EINVAL;
525
526 rinfo.num_fields = report->maxfield;
527
528 if (copy_to_user((void *) arg, &rinfo, sizeof(rinfo)))
529 return -EFAULT;
530 return 0;
531
532 case HIDIOCGFIELDINFO:
533 if (copy_from_user(&finfo, (void *) arg, sizeof(finfo)))
534 return -EFAULT;
535 rinfo.report_type = finfo.report_type;
536 rinfo.report_id = finfo.report_id;
537 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
538 return -EINVAL;
539
540 if (finfo.field_index >= report->maxfield)
541 return -EINVAL;
542
543 field = report->field[finfo.field_index];
544 memset(&finfo, 0, sizeof(finfo));
545 finfo.report_type = rinfo.report_type;
546 finfo.report_id = rinfo.report_id;
547 finfo.field_index = field->report_count - 1;
548 finfo.maxusage = field->maxusage;
549 finfo.flags = field->flags;
550 finfo.physical = field->physical;
551 finfo.logical = field->logical;
552 finfo.application = field->application;
553 finfo.logical_minimum = field->logical_minimum;
554 finfo.logical_maximum = field->logical_maximum;
555 finfo.physical_minimum = field->physical_minimum;
556 finfo.physical_maximum = field->physical_maximum;
557 finfo.unit_exponent = field->unit_exponent;
558 finfo.unit = field->unit;
559
560 if (copy_to_user((void *) arg, &finfo, sizeof(finfo)))
561 return -EFAULT;
562 return 0;
563
564 case HIDIOCGUCODE:
565 if (copy_from_user(uref, (void *) arg, sizeof(*uref)))
566 return -EFAULT;
567
568 rinfo.report_type = uref->report_type;
569 rinfo.report_id = uref->report_id;
570 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
571 return -EINVAL;
572
573 if (uref->field_index >= report->maxfield)
574 return -EINVAL;
575
576 field = report->field[uref->field_index];
577 if (uref->usage_index >= field->maxusage)
578 return -EINVAL;
579
580 uref->usage_code = field->usage[uref->usage_index].hid;
581
582 if (copy_to_user((void *) arg, uref, sizeof(*uref)))
583 return -EFAULT;
584 return 0;
585
586 case HIDIOCGUSAGE:
587 case HIDIOCSUSAGE:
588 case HIDIOCGUSAGES:
589 case HIDIOCSUSAGES:
590 case HIDIOCGCOLLECTIONINDEX:
591 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
592 if (copy_from_user(&uref_multi, (void *) arg,
593 sizeof(uref_multi)))
594 return -EFAULT;
595 } else {
596 if (copy_from_user(uref, (void *) arg, sizeof(*uref)))
597 return -EFAULT;
598 }
599
600 if (cmd != HIDIOCGUSAGE &&
601 cmd != HIDIOCGUSAGES &&
602 uref->report_type == HID_REPORT_TYPE_INPUT)
603 return -EINVAL;
604
605 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
606 field = hiddev_lookup_usage(hid, uref);
607 if (field == NULL)
608 return -EINVAL;
609 } else {
610 rinfo.report_type = uref->report_type;
611 rinfo.report_id = uref->report_id;
612 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
613 return -EINVAL;
614
615 if (uref->field_index >= report->maxfield)
616 return -EINVAL;
617
618 field = report->field[uref->field_index];
619 if (uref->usage_index >= field->maxusage)
620 return -EINVAL;
621
622 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
623 if (uref_multi.num_values >= HID_MAX_USAGES ||
624 uref->usage_index >= field->maxusage ||
625 (uref->usage_index + uref_multi.num_values) >= field->maxusage)
626 return -EINVAL;
627 }
628 }
629
630 switch (cmd) {
631 case HIDIOCGUSAGE:
632 uref->value = field->value[uref->usage_index];
633 return copy_to_user((void *) arg, uref, sizeof(*uref));
634
635 case HIDIOCSUSAGE:
636 field->value[uref->usage_index] = uref->value;
637 return 0;
638
639 case HIDIOCGCOLLECTIONINDEX:
640 return field->usage[uref->usage_index].collection_index;
641 case HIDIOCGUSAGES:
642 for (i = 0; i < uref_multi.num_values; i++)
643 uref_multi.values[i] =
644 field->value[uref->usage_index + i];
645 if (copy_to_user((void *) arg, &uref_multi,
646 sizeof(uref_multi)))
647 return -EFAULT;
648 return 0;
649 case HIDIOCSUSAGES:
650 for (i = 0; i < uref_multi.num_values; i++)
651 field->value[uref->usage_index + i] =
652 uref_multi.values[i];
653 return 0;
654 }
655 break;
656
657 case HIDIOCGCOLLECTIONINFO:
658 if (copy_from_user(&cinfo, (void *) arg, sizeof(cinfo)))
659 return -EFAULT;
660
661 if (cinfo.index >= hid->maxcollection)
662 return -EINVAL;
663
664 cinfo.type = hid->collection[cinfo.index].type;
665 cinfo.usage = hid->collection[cinfo.index].usage;
666 cinfo.level = hid->collection[cinfo.index].level;
667
668 if (copy_to_user((void *) arg, &cinfo, sizeof(cinfo)))
669 return -EFAULT;
670 return 0;
671
672 default:
673
674 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
675 return -EINVAL;
676
677 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
678 int len;
679 if (!hid->name) return 0;
680 len = strlen(hid->name) + 1;
681 if (len > _IOC_SIZE(cmd)) len = _IOC_SIZE(cmd);
682 return copy_to_user((char *) arg, hid->name, len) ?
683 -EFAULT : len;
684 }
685 }
686 return -EINVAL;
687 }
688
689 static struct file_operations hiddev_fops = {
690 owner: THIS_MODULE,
691 read: hiddev_read,
692 write: hiddev_write,
693 poll: hiddev_poll,
694 open: hiddev_open,
695 release: hiddev_release,
696 ioctl: hiddev_ioctl,
697 fasync: hiddev_fasync,
698 };
699
700 /*
701 * This is where hid.c calls us to connect a hid device to the hiddev driver
702 */
hiddev_connect(struct hid_device * hid)703 int hiddev_connect(struct hid_device *hid)
704 {
705 struct hiddev *hiddev;
706 int minor, i;
707 char devfs_name[16];
708
709
710
711 if ((hid->quirks & HID_QUIRK_HIDDEV) == 0) {
712 for (i = 0; i < hid->maxcollection; i++)
713 if (hid->collection[i].type ==
714 HID_COLLECTION_APPLICATION &&
715 !IS_INPUT_APPLICATION(hid->collection[i].usage))
716 break;
717
718 if (i == hid->maxcollection)
719 return -1;
720 }
721
722 for (minor = 0; minor < HIDDEV_MINORS && hiddev_table[minor]; minor++);
723 if (minor == HIDDEV_MINORS) {
724 printk(KERN_ERR "hiddev: no more free hiddev devices\n");
725 return -1;
726 }
727
728 if (!(hiddev = kmalloc(sizeof(struct hiddev), GFP_KERNEL)))
729 return -1;
730 memset(hiddev, 0, sizeof(struct hiddev));
731
732 init_waitqueue_head(&hiddev->wait);
733
734 hiddev->minor = minor;
735 hiddev_table[minor] = hiddev;
736
737 hiddev->hid = hid;
738 hiddev->exist = 1;
739
740 sprintf(devfs_name, "hiddev%d", minor);
741 hiddev->devfs = devfs_register(hiddev_devfs_handle, devfs_name,
742 DEVFS_FL_DEFAULT, USB_MAJOR,
743 minor + HIDDEV_MINOR_BASE,
744 S_IFCHR | S_IRUGO | S_IWUSR,
745 &hiddev_fops, NULL);
746 hid->minor = minor;
747 hid->hiddev = hiddev;
748
749 return 0;
750 }
751
752 /*
753 * This is where hid.c calls us to disconnect a hiddev device from the
754 * corresponding hid device (usually because the usb device has disconnected)
755 */
hiddev_disconnect(struct hid_device * hid)756 void hiddev_disconnect(struct hid_device *hid)
757 {
758 struct hiddev *hiddev = hid->hiddev;
759
760 hiddev->exist = 0;
761
762 if (hiddev->open) {
763 hid_close(hiddev->hid);
764 wake_up_interruptible(&hiddev->wait);
765 } else {
766 hiddev_cleanup(hiddev);
767 }
768 }
769
770 /* Currently this driver is a USB driver. It's not a conventional one in
771 * the sense that it doesn't probe at the USB level. Instead it waits to
772 * be connected by HID through the hiddev_connect / hiddev_disconnect
773 * routines. The reason to register as a USB device is to gain part of the
774 * minor number space from the USB major.
775 *
776 * In theory, should the HID code be generalized to more than one physical
777 * medium (say, IEEE 1384), this driver will probably need to register its
778 * own major number, and in doing so, no longer need to register with USB.
779 * At that point the probe routine and hiddev_driver struct below will no
780 * longer be useful.
781 */
782
783
784 /* We never attach in this manner, and rely on HID to connect us. This
785 * is why there is no disconnect routine defined in the usb_driver either.
786 */
hiddev_usbd_probe(struct usb_device * dev,unsigned int ifnum,const struct usb_device_id * hiddev_info)787 static void *hiddev_usbd_probe(struct usb_device *dev, unsigned int ifnum,
788 const struct usb_device_id *hiddev_info)
789 {
790 return NULL;
791 }
792
793
794 static /* const */ struct usb_driver hiddev_driver = {
795 name: "hiddev",
796 probe: hiddev_usbd_probe,
797 fops: &hiddev_fops,
798 minor: HIDDEV_MINOR_BASE
799 };
800
hiddev_init(void)801 int __init hiddev_init(void)
802 {
803 hiddev_devfs_handle =
804 devfs_mk_dir(devfs_find_handle(NULL, "usb", 0, 0, 0, 0), "hid", NULL);
805 usb_register(&hiddev_driver);
806 return 0;
807 }
808
hiddev_exit(void)809 void __exit hiddev_exit(void)
810 {
811 devfs_unregister(hiddev_devfs_handle);
812 usb_deregister(&hiddev_driver);
813 }
814