Initial commit
[wrt350n-kernel.git] / drivers / hid / usbhid / hiddev.c
blob5fc4019956ba2ffe17b2d5dda04206aa7b5d9a4d
1 /*
2 * Copyright (c) 2001 Paul Stewart
3 * Copyright (c) 2001 Vojtech Pavlik
5 * HID char devices, giving access to raw HID device events.
7 */
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.
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.
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
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>
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"
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
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;
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;
68 static struct hiddev *hiddev_table[HIDDEV_MINORS];
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.
76 static struct hid_report *
77 hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
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;
85 if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
86 rinfo->report_type > HID_REPORT_TYPE_MAX)
87 return NULL;
89 report_enum = hid->report_enum +
90 (rinfo->report_type - HID_REPORT_TYPE_MIN);
92 switch (flags) {
93 case 0: /* Nothing to do -- report_id is already set correctly */
94 break;
96 case HID_REPORT_ID_FIRST:
97 if (list_empty(&report_enum->report_list))
98 return NULL;
100 list = report_enum->report_list.next;
101 report = list_entry(list, struct hid_report, list);
102 rinfo->report_id = report->id;
103 break;
105 case HID_REPORT_ID_NEXT:
106 report = report_enum->report_id_hash[rid];
107 if (!report)
108 return NULL;
110 list = report->list.next;
111 if (list == &report_enum->report_list)
112 return NULL;
114 report = list_entry(list, struct hid_report, list);
115 rinfo->report_id = report->id;
116 break;
118 default:
119 return NULL;
122 return report_enum->report_id_hash[rinfo->report_id];
126 * Perform an exhaustive search of the report table for a usage, given its
127 * type and usage id.
129 static struct hid_field *
130 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
132 int i, j;
133 struct hid_report *report;
134 struct hid_report_enum *report_enum;
135 struct hid_field *field;
137 if (uref->report_type < HID_REPORT_TYPE_MIN ||
138 uref->report_type > HID_REPORT_TYPE_MAX)
139 return NULL;
141 report_enum = hid->report_enum +
142 (uref->report_type - HID_REPORT_TYPE_MIN);
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;
158 return NULL;
161 static void hiddev_send_event(struct hid_device *hid,
162 struct hiddev_usage_ref *uref)
164 struct hiddev *hiddev = hid->hiddev;
165 struct hiddev_list *list;
166 unsigned long flags;
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);
178 spin_unlock_irqrestore(&hiddev->list_lock, flags);
180 wake_up_interruptible(&hiddev->wait);
184 * This is where hid.c calls into hiddev to pass an event that occurred over
185 * the interrupt pipe
187 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
188 struct hid_usage *usage, __s32 value)
190 unsigned type = field->report_type;
191 struct hiddev_usage_ref uref;
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;
203 hiddev_send_event(hid, &uref);
205 EXPORT_SYMBOL_GPL(hiddev_hid_event);
207 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
209 unsigned type = report->type;
210 struct hiddev_usage_ref uref;
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;
220 hiddev_send_event(hid, &uref);
224 * fasync file op
226 static int hiddev_fasync(int fd, struct file *file, int on)
228 int retval;
229 struct hiddev_list *list = file->private_data;
231 retval = fasync_helper(fd, file, on, &list->fasync);
233 return retval < 0 ? retval : 0;
238 * release file op
240 static int hiddev_release(struct inode * inode, struct file * file)
242 struct hiddev_list *list = file->private_data;
243 unsigned long flags;
245 hiddev_fasync(-1, file, 0);
247 spin_lock_irqsave(&list->hiddev->list_lock, flags);
248 list_del(&list->node);
249 spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
251 if (!--list->hiddev->open) {
252 if (list->hiddev->exist)
253 usbhid_close(list->hiddev->hid);
254 else
255 kfree(list->hiddev);
258 kfree(list);
260 return 0;
264 * open file op
266 static int hiddev_open(struct inode *inode, struct file *file)
268 struct hiddev_list *list;
269 unsigned long flags;
271 int i = iminor(inode) - HIDDEV_MINOR_BASE;
273 if (i >= HIDDEV_MINORS || !hiddev_table[i])
274 return -ENODEV;
276 if (!(list = kzalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
277 return -ENOMEM;
279 list->hiddev = hiddev_table[i];
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);
285 file->private_data = list;
287 if (!list->hiddev->open++)
288 if (list->hiddev->exist)
289 usbhid_open(hiddev_table[i]->hid);
291 return 0;
295 * "write" file op
297 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
299 return -EINVAL;
303 * "read" file op
305 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
307 DECLARE_WAITQUEUE(wait, current);
308 struct hiddev_list *list = file->private_data;
309 int event_size;
310 int retval = 0;
312 event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
313 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
315 if (count < event_size)
316 return 0;
318 while (retval == 0) {
319 if (list->head == list->tail) {
320 add_wait_queue(&list->hiddev->wait, &wait);
321 set_current_state(TASK_INTERRUPTIBLE);
323 while (list->head == list->tail) {
324 if (file->f_flags & O_NONBLOCK) {
325 retval = -EAGAIN;
326 break;
328 if (signal_pending(current)) {
329 retval = -ERESTARTSYS;
330 break;
332 if (!list->hiddev->exist) {
333 retval = -EIO;
334 break;
337 schedule();
338 set_current_state(TASK_INTERRUPTIBLE);
341 set_current_state(TASK_RUNNING);
342 remove_wait_queue(&list->hiddev->wait, &wait);
345 if (retval)
346 return retval;
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);
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);
369 list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
374 return retval;
378 * "poll" file op
379 * No kernel lock - fine
381 static unsigned int hiddev_poll(struct file *file, poll_table *wait)
383 struct hiddev_list *list = file->private_data;
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;
394 * "ioctl" file op
396 static int hiddev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
398 struct hiddev_list *list = file->private_data;
399 struct hiddev *hiddev = list->hiddev;
400 struct hid_device *hid = hiddev->hid;
401 struct usb_device *dev = hid_to_usb_dev(hid);
402 struct hiddev_collection_info cinfo;
403 struct hiddev_report_info rinfo;
404 struct hiddev_field_info finfo;
405 struct hiddev_usage_ref_multi *uref_multi = NULL;
406 struct hiddev_usage_ref *uref;
407 struct hiddev_devinfo dinfo;
408 struct hid_report *report;
409 struct hid_field *field;
410 struct usbhid_device *usbhid = hid->driver_data;
411 void __user *user_arg = (void __user *)arg;
412 int i;
414 if (!hiddev->exist)
415 return -EIO;
417 switch (cmd) {
419 case HIDIOCGVERSION:
420 return put_user(HID_VERSION, (int __user *)arg);
422 case HIDIOCAPPLICATION:
423 if (arg < 0 || arg >= hid->maxapplication)
424 return -EINVAL;
426 for (i = 0; i < hid->maxcollection; i++)
427 if (hid->collection[i].type ==
428 HID_COLLECTION_APPLICATION && arg-- == 0)
429 break;
431 if (i == hid->maxcollection)
432 return -EINVAL;
434 return hid->collection[i].usage;
436 case HIDIOCGDEVINFO:
437 dinfo.bustype = BUS_USB;
438 dinfo.busnum = dev->bus->busnum;
439 dinfo.devnum = dev->devnum;
440 dinfo.ifnum = usbhid->ifnum;
441 dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
442 dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
443 dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
444 dinfo.num_applications = hid->maxapplication;
445 if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
446 return -EFAULT;
448 return 0;
450 case HIDIOCGFLAG:
451 if (put_user(list->flags, (int __user *)arg))
452 return -EFAULT;
454 return 0;
456 case HIDIOCSFLAG:
458 int newflags;
459 if (get_user(newflags, (int __user *)arg))
460 return -EFAULT;
462 if ((newflags & ~HIDDEV_FLAGS) != 0 ||
463 ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
464 (newflags & HIDDEV_FLAG_UREF) == 0))
465 return -EINVAL;
467 list->flags = newflags;
469 return 0;
472 case HIDIOCGSTRING:
474 int idx, len;
475 char *buf;
477 if (get_user(idx, (int __user *)arg))
478 return -EFAULT;
480 if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
481 return -ENOMEM;
483 if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
484 kfree(buf);
485 return -EINVAL;
488 if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
489 kfree(buf);
490 return -EFAULT;
493 kfree(buf);
495 return len;
498 case HIDIOCINITREPORT:
499 usbhid_init_reports(hid);
501 return 0;
503 case HIDIOCGREPORT:
504 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
505 return -EFAULT;
507 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
508 return -EINVAL;
510 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
511 return -EINVAL;
513 usbhid_submit_report(hid, report, USB_DIR_IN);
514 usbhid_wait_io(hid);
516 return 0;
518 case HIDIOCSREPORT:
519 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
520 return -EFAULT;
522 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
523 return -EINVAL;
525 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
526 return -EINVAL;
528 usbhid_submit_report(hid, report, USB_DIR_OUT);
529 usbhid_wait_io(hid);
531 return 0;
533 case HIDIOCGREPORTINFO:
534 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
535 return -EFAULT;
537 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
538 return -EINVAL;
540 rinfo.num_fields = report->maxfield;
542 if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
543 return -EFAULT;
545 return 0;
547 case HIDIOCGFIELDINFO:
548 if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
549 return -EFAULT;
550 rinfo.report_type = finfo.report_type;
551 rinfo.report_id = finfo.report_id;
552 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
553 return -EINVAL;
555 if (finfo.field_index >= report->maxfield)
556 return -EINVAL;
558 field = report->field[finfo.field_index];
559 memset(&finfo, 0, sizeof(finfo));
560 finfo.report_type = rinfo.report_type;
561 finfo.report_id = rinfo.report_id;
562 finfo.field_index = field->report_count - 1;
563 finfo.maxusage = field->maxusage;
564 finfo.flags = field->flags;
565 finfo.physical = field->physical;
566 finfo.logical = field->logical;
567 finfo.application = field->application;
568 finfo.logical_minimum = field->logical_minimum;
569 finfo.logical_maximum = field->logical_maximum;
570 finfo.physical_minimum = field->physical_minimum;
571 finfo.physical_maximum = field->physical_maximum;
572 finfo.unit_exponent = field->unit_exponent;
573 finfo.unit = field->unit;
575 if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
576 return -EFAULT;
578 return 0;
580 case HIDIOCGUCODE:
581 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
582 if (!uref_multi)
583 return -ENOMEM;
584 uref = &uref_multi->uref;
585 if (copy_from_user(uref, user_arg, sizeof(*uref)))
586 goto fault;
588 rinfo.report_type = uref->report_type;
589 rinfo.report_id = uref->report_id;
590 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
591 goto inval;
593 if (uref->field_index >= report->maxfield)
594 goto inval;
596 field = report->field[uref->field_index];
597 if (uref->usage_index >= field->maxusage)
598 goto inval;
600 uref->usage_code = field->usage[uref->usage_index].hid;
602 if (copy_to_user(user_arg, uref, sizeof(*uref)))
603 goto fault;
605 kfree(uref_multi);
606 return 0;
608 case HIDIOCGUSAGE:
609 case HIDIOCSUSAGE:
610 case HIDIOCGUSAGES:
611 case HIDIOCSUSAGES:
612 case HIDIOCGCOLLECTIONINDEX:
613 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
614 if (!uref_multi)
615 return -ENOMEM;
616 uref = &uref_multi->uref;
617 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
618 if (copy_from_user(uref_multi, user_arg,
619 sizeof(*uref_multi)))
620 goto fault;
621 } else {
622 if (copy_from_user(uref, user_arg, sizeof(*uref)))
623 goto fault;
626 if (cmd != HIDIOCGUSAGE &&
627 cmd != HIDIOCGUSAGES &&
628 uref->report_type == HID_REPORT_TYPE_INPUT)
629 goto inval;
631 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
632 field = hiddev_lookup_usage(hid, uref);
633 if (field == NULL)
634 goto inval;
635 } else {
636 rinfo.report_type = uref->report_type;
637 rinfo.report_id = uref->report_id;
638 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
639 goto inval;
641 if (uref->field_index >= report->maxfield)
642 goto inval;
644 field = report->field[uref->field_index];
646 if (cmd == HIDIOCGCOLLECTIONINDEX) {
647 if (uref->usage_index >= field->maxusage)
648 goto inval;
649 } else if (uref->usage_index >= field->report_count)
650 goto inval;
652 else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
653 (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
654 uref->usage_index + uref_multi->num_values > field->report_count))
655 goto inval;
658 switch (cmd) {
659 case HIDIOCGUSAGE:
660 uref->value = field->value[uref->usage_index];
661 if (copy_to_user(user_arg, uref, sizeof(*uref)))
662 goto fault;
663 goto goodreturn;
665 case HIDIOCSUSAGE:
666 field->value[uref->usage_index] = uref->value;
667 goto goodreturn;
669 case HIDIOCGCOLLECTIONINDEX:
670 kfree(uref_multi);
671 return field->usage[uref->usage_index].collection_index;
672 case HIDIOCGUSAGES:
673 for (i = 0; i < uref_multi->num_values; i++)
674 uref_multi->values[i] =
675 field->value[uref->usage_index + i];
676 if (copy_to_user(user_arg, uref_multi,
677 sizeof(*uref_multi)))
678 goto fault;
679 goto goodreturn;
680 case HIDIOCSUSAGES:
681 for (i = 0; i < uref_multi->num_values; i++)
682 field->value[uref->usage_index + i] =
683 uref_multi->values[i];
684 goto goodreturn;
687 goodreturn:
688 kfree(uref_multi);
689 return 0;
690 fault:
691 kfree(uref_multi);
692 return -EFAULT;
693 inval:
694 kfree(uref_multi);
695 return -EINVAL;
697 case HIDIOCGCOLLECTIONINFO:
698 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
699 return -EFAULT;
701 if (cinfo.index >= hid->maxcollection)
702 return -EINVAL;
704 cinfo.type = hid->collection[cinfo.index].type;
705 cinfo.usage = hid->collection[cinfo.index].usage;
706 cinfo.level = hid->collection[cinfo.index].level;
708 if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
709 return -EFAULT;
710 return 0;
712 default:
714 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
715 return -EINVAL;
717 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
718 int len;
719 if (!hid->name)
720 return 0;
721 len = strlen(hid->name) + 1;
722 if (len > _IOC_SIZE(cmd))
723 len = _IOC_SIZE(cmd);
724 return copy_to_user(user_arg, hid->name, len) ?
725 -EFAULT : len;
728 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
729 int len;
730 if (!hid->phys)
731 return 0;
732 len = strlen(hid->phys) + 1;
733 if (len > _IOC_SIZE(cmd))
734 len = _IOC_SIZE(cmd);
735 return copy_to_user(user_arg, hid->phys, len) ?
736 -EFAULT : len;
739 return -EINVAL;
742 #ifdef CONFIG_COMPAT
743 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
745 struct inode *inode = file->f_path.dentry->d_inode;
746 return hiddev_ioctl(inode, file, cmd, (unsigned long)compat_ptr(arg));
748 #endif
750 static const struct file_operations hiddev_fops = {
751 .owner = THIS_MODULE,
752 .read = hiddev_read,
753 .write = hiddev_write,
754 .poll = hiddev_poll,
755 .open = hiddev_open,
756 .release = hiddev_release,
757 .ioctl = hiddev_ioctl,
758 .fasync = hiddev_fasync,
759 #ifdef CONFIG_COMPAT
760 .compat_ioctl = hiddev_compat_ioctl,
761 #endif
764 static struct usb_class_driver hiddev_class = {
765 .name = "hiddev%d",
766 .fops = &hiddev_fops,
767 .minor_base = HIDDEV_MINOR_BASE,
771 * This is where hid.c calls us to connect a hid device to the hiddev driver
773 int hiddev_connect(struct hid_device *hid)
775 struct hiddev *hiddev;
776 struct usbhid_device *usbhid = hid->driver_data;
777 int i;
778 int retval;
780 for (i = 0; i < hid->maxcollection; i++)
781 if (hid->collection[i].type ==
782 HID_COLLECTION_APPLICATION &&
783 !IS_INPUT_APPLICATION(hid->collection[i].usage))
784 break;
786 if (i == hid->maxcollection && (hid->quirks & HID_QUIRK_HIDDEV) == 0)
787 return -1;
789 if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
790 return -1;
792 retval = usb_register_dev(usbhid->intf, &hiddev_class);
793 if (retval) {
794 err_hid("Not able to get a minor for this device.");
795 kfree(hiddev);
796 return -1;
799 init_waitqueue_head(&hiddev->wait);
800 INIT_LIST_HEAD(&hiddev->list);
801 spin_lock_init(&hiddev->list_lock);
802 hiddev->hid = hid;
803 hiddev->exist = 1;
805 hid->minor = usbhid->intf->minor;
806 hid->hiddev = hiddev;
808 hiddev_table[usbhid->intf->minor - HIDDEV_MINOR_BASE] = hiddev;
810 return 0;
814 * This is where hid.c calls us to disconnect a hiddev device from the
815 * corresponding hid device (usually because the usb device has disconnected)
817 static struct usb_class_driver hiddev_class;
818 void hiddev_disconnect(struct hid_device *hid)
820 struct hiddev *hiddev = hid->hiddev;
821 struct usbhid_device *usbhid = hid->driver_data;
823 hiddev->exist = 0;
825 hiddev_table[hiddev->hid->minor - HIDDEV_MINOR_BASE] = NULL;
826 usb_deregister_dev(usbhid->intf, &hiddev_class);
828 if (hiddev->open) {
829 usbhid_close(hiddev->hid);
830 wake_up_interruptible(&hiddev->wait);
831 } else {
832 kfree(hiddev);
836 /* Currently this driver is a USB driver. It's not a conventional one in
837 * the sense that it doesn't probe at the USB level. Instead it waits to
838 * be connected by HID through the hiddev_connect / hiddev_disconnect
839 * routines. The reason to register as a USB device is to gain part of the
840 * minor number space from the USB major.
842 * In theory, should the HID code be generalized to more than one physical
843 * medium (say, IEEE 1384), this driver will probably need to register its
844 * own major number, and in doing so, no longer need to register with USB.
845 * At that point the probe routine and hiddev_driver struct below will no
846 * longer be useful.
850 /* We never attach in this manner, and rely on HID to connect us. This
851 * is why there is no disconnect routine defined in the usb_driver either.
853 static int hiddev_usbd_probe(struct usb_interface *intf,
854 const struct usb_device_id *hiddev_info)
856 return -ENODEV;
860 static /* const */ struct usb_driver hiddev_driver = {
861 .name = "hiddev",
862 .probe = hiddev_usbd_probe,
865 int __init hiddev_init(void)
867 return usb_register(&hiddev_driver);
870 void hiddev_exit(void)
872 usb_deregister(&hiddev_driver);