Newer
Older
/*
* Copyright (c) 2001 Paul Stewart
* Copyright (c) 2001 Vojtech Pavlik
*
* HID char devices, giving access to raw HID device events.
*
*/
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Should you need to contact me, the author, you can do so either by
* e-mail - mail your message to Paul Stewart <stewart@wetlogic.net>
*/
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/smp_lock.h>
#include <linux/input.h>
#include <linux/usb.h>
#ifdef CONFIG_USB_DYNAMIC_MINORS
#define HIDDEV_MINOR_BASE 0
#define HIDDEV_MINORS 256
#else
#define HIDDEV_MINOR_BASE 96
#define HIDDEV_MINORS 16
#endif
#define HIDDEV_BUFFER_SIZE 64
struct hiddev {
int exist;
int open;
struct mutex existancelock;
struct list_head list;
spinlock_t list_lock;
};
struct hiddev_list {
struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
int head;
int tail;
unsigned flags;
struct fasync_struct *fasync;
struct hiddev *hiddev;
struct list_head node;
struct mutex thread_lock;
};
static struct hiddev *hiddev_table[HIDDEV_MINORS];
/*
* Find a report, given the report's type and ID. The ID can be specified
* indirectly by REPORT_ID_FIRST (which returns the first report of the given
* type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
* given type which follows old_id.
*/
static struct hid_report *
hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
{
unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK;
struct hid_report *report;
struct list_head *list;
if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
rinfo->report_type > HID_REPORT_TYPE_MAX)
return NULL;
report_enum = hid->report_enum +
(rinfo->report_type - HID_REPORT_TYPE_MIN);
switch (flags) {
case 0: /* Nothing to do -- report_id is already set correctly */
break;
case HID_REPORT_ID_FIRST:
if (list_empty(&report_enum->report_list))
list = report_enum->report_list.next;
report = list_entry(list, struct hid_report, list);
rinfo->report_id = report->id;
report = report_enum->report_id_hash[rid];
if (!report)
list = report->list.next;
if (list == &report_enum->report_list)
return NULL;
report = list_entry(list, struct hid_report, list);
rinfo->report_id = report->id;
default:
return NULL;
}
return report_enum->report_id_hash[rinfo->report_id];
}
/*
* Perform an exhaustive search of the report table for a usage, given its
* type and usage id.
*/
static struct hid_field *
hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
{
int i, j;
struct hid_report *report;
struct hid_report_enum *report_enum;
struct hid_field *field;
if (uref->report_type < HID_REPORT_TYPE_MIN ||
uref->report_type > HID_REPORT_TYPE_MAX)
return NULL;
report_enum = hid->report_enum +
(uref->report_type - HID_REPORT_TYPE_MIN);
list_for_each_entry(report, &report_enum->report_list, list) {
for (i = 0; i < report->maxfield; i++) {
field = report->field[i];
for (j = 0; j < field->maxusage; j++) {
if (field->usage[j].hid == uref->usage_code) {
uref->report_id = report->id;
uref->field_index = i;
uref->usage_index = j;
return field;
}
}
}
return NULL;
}
static void hiddev_send_event(struct hid_device *hid,
struct hiddev_usage_ref *uref)
{
struct hiddev *hiddev = hid->hiddev;
struct hiddev_list *list;
unsigned long flags;
spin_lock_irqsave(&hiddev->list_lock, flags);
list_for_each_entry(list, &hiddev->list, node) {
if (uref->field_index != HID_FIELD_INDEX_NONE ||
(list->flags & HIDDEV_FLAG_REPORT) != 0) {
list->buffer[list->head] = *uref;
list->head = (list->head + 1) &
(HIDDEV_BUFFER_SIZE - 1);
kill_fasync(&list->fasync, SIGIO, POLL_IN);
}
}
spin_unlock_irqrestore(&hiddev->list_lock, flags);
wake_up_interruptible(&hiddev->wait);
}
/*
* This is where hid.c calls into hiddev to pass an event that occurred over
* the interrupt pipe
*/
void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
struct hid_usage *usage, __s32 value)
{
unsigned type = field->report_type;
struct hiddev_usage_ref uref;
((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
uref.report_id = field->report->id;
uref.field_index = field->index;
uref.usage_index = (usage - field->usage);
uref.usage_code = usage->hid;
uref.value = value;
hiddev_send_event(hid, &uref);
}
void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
{
unsigned type = report->type;
struct hiddev_usage_ref uref;
memset(&uref, 0, sizeof(uref));
((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
uref.report_id = report->id;
uref.field_index = HID_FIELD_INDEX_NONE;
hiddev_send_event(hid, &uref);
}
/*
* fasync file op
*/
static int hiddev_fasync(int fd, struct file *file, int on)
{
int retval;
struct hiddev_list *list = file->private_data;
return retval < 0 ? retval : 0;
}
/*
* release file op
*/
static int hiddev_release(struct inode * inode, struct file * file)
{
struct hiddev_list *list = file->private_data;
unsigned long flags;
spin_lock_irqsave(&list->hiddev->list_lock, flags);
list_del(&list->node);
spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
else
kfree(list->hiddev);
}
kfree(list);
return 0;
}
/*
* open file op
*/
static int hiddev_open(struct inode *inode, struct file *file)
{
if (i >= HIDDEV_MINORS || i < 0 || !hiddev_table[i])
if (!(list = kzalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
mutex_init(&list->thread_lock);
/*
* no need for locking because the USB major number
* is shared which usbcore guards against disconnect
*/
if (list->hiddev->exist) {
if (!list->hiddev->open++) {
res = usbhid_open(hiddev_table[i]->hid);
if (res < 0) {
res = -EIO;
goto bail;
}
}
} else {
res = -ENODEV;
goto bail;
}
spin_lock_irq(&list->hiddev->list_lock);
list_add_tail(&list->node, &hiddev_table[i]->list);
spin_unlock_irq(&list->hiddev->list_lock);
bail:
file->private_data = NULL;
}
/*
* "write" file op
*/
static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
{
return -EINVAL;
}
/*
* "read" file op
*/
static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
{
DECLARE_WAITQUEUE(wait, current);
struct hiddev_list *list = file->private_data;
int event_size;
event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
if (count < event_size)
return 0;
/* lock against other threads */
retval = mutex_lock_interruptible(&list->thread_lock);
if (retval)
return -ERESTARTSYS;
while (retval == 0) {
if (list->head == list->tail) {
prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);
while (list->head == list->tail) {
if (file->f_flags & O_NONBLOCK) {
retval = -EAGAIN;
break;
}
if (signal_pending(current)) {
retval = -ERESTARTSYS;
break;
}
if (!list->hiddev->exist) {
retval = -EIO;
break;
}
/* let O_NONBLOCK tasks run */
mutex_unlock(&list->thread_lock);
if (mutex_lock_interruptible(&list->thread_lock))
return -EINTR;
finish_wait(&list->hiddev->wait, &wait);
if (retval) {
mutex_unlock(&list->thread_lock);
while (list->head != list->tail &&
retval + event_size <= count) {
if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
event.hid = list->buffer[list->tail].usage_code;
event.value = list->buffer[list->tail].value;
if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {
mutex_unlock(&list->thread_lock);
retval += sizeof(struct hiddev_event);
}
} else {
if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
(list->flags & HIDDEV_FLAG_REPORT) != 0) {
if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {
mutex_unlock(&list->thread_lock);
retval += sizeof(struct hiddev_usage_ref);
}
}
list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
}
}
mutex_unlock(&list->thread_lock);
return retval;
}
/*
* "poll" file op
* No kernel lock - fine
*/
static unsigned int hiddev_poll(struct file *file, poll_table *wait)
{
struct hiddev_list *list = file->private_data;
poll_wait(file, &list->hiddev->wait, wait);
if (list->head != list->tail)
return POLLIN | POLLRDNORM;
if (!list->hiddev->exist)
return POLLERR | POLLHUP;
return 0;
}
/*
* "ioctl" file op
*/
static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
{
struct hid_device *hid = hiddev->hid;
struct hiddev_report_info rinfo;
struct hiddev_usage_ref_multi *uref_multi = NULL;
struct hiddev_usage_ref *uref;
struct hid_report *report;
struct hid_field *field;
int i;
uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
if (!uref_multi)
return -ENOMEM;
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
uref = &uref_multi->uref;
if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
if (copy_from_user(uref_multi, user_arg,
sizeof(*uref_multi)))
goto fault;
} else {
if (copy_from_user(uref, user_arg, sizeof(*uref)))
goto fault;
}
switch (cmd) {
case HIDIOCGUCODE:
rinfo.report_type = uref->report_type;
rinfo.report_id = uref->report_id;
if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
goto inval;
if (uref->field_index >= report->maxfield)
goto inval;
field = report->field[uref->field_index];
if (uref->usage_index >= field->maxusage)
goto inval;
uref->usage_code = field->usage[uref->usage_index].hid;
if (copy_to_user(user_arg, uref, sizeof(*uref)))
goto fault;
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
default:
if (cmd != HIDIOCGUSAGE &&
cmd != HIDIOCGUSAGES &&
uref->report_type == HID_REPORT_TYPE_INPUT)
goto inval;
if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
field = hiddev_lookup_usage(hid, uref);
if (field == NULL)
goto inval;
} else {
rinfo.report_type = uref->report_type;
rinfo.report_id = uref->report_id;
if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
goto inval;
if (uref->field_index >= report->maxfield)
goto inval;
field = report->field[uref->field_index];
if (cmd == HIDIOCGCOLLECTIONINDEX) {
if (uref->usage_index >= field->maxusage)
goto inval;
} else if (uref->usage_index >= field->report_count)
goto inval;
else if ((cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) &&
(uref_multi->num_values > HID_MAX_MULTI_USAGES ||
uref->usage_index + uref_multi->num_values > field->report_count))
goto inval;
}
switch (cmd) {
case HIDIOCGUSAGE:
uref->value = field->value[uref->usage_index];
if (copy_to_user(user_arg, uref, sizeof(*uref)))
goto fault;
goto goodreturn;
case HIDIOCSUSAGE:
field->value[uref->usage_index] = uref->value;
goto goodreturn;
case HIDIOCGCOLLECTIONINDEX:
kfree(uref_multi);
return field->usage[uref->usage_index].collection_index;
case HIDIOCGUSAGES:
for (i = 0; i < uref_multi->num_values; i++)
uref_multi->values[i] =
field->value[uref->usage_index + i];
if (copy_to_user(user_arg, uref_multi,
sizeof(*uref_multi)))
goto fault;
goto goodreturn;
case HIDIOCSUSAGES:
for (i = 0; i < uref_multi->num_values; i++)
field->value[uref->usage_index + i] =
uref_multi->values[i];
goto goodreturn;
}
goodreturn:
kfree(uref_multi);
return 0;
fault:
kfree(uref_multi);
return -EFAULT;
inval:
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
kfree(uref_multi);
return -EINVAL;
}
}
static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
{
struct hid_device *hid = hiddev->hid;
struct usb_device *dev = hid_to_usb_dev(hid);
int idx, len;
char *buf;
if (get_user(idx, (int __user *)user_arg))
return -EFAULT;
if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
return -ENOMEM;
if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
kfree(buf);
return -EINVAL;
}
if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
kfree(buf);
return -EFAULT;
}
kfree(buf);
return len;
}
static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct hiddev_list *list = file->private_data;
struct hiddev *hiddev = list->hiddev;
struct hid_device *hid = hiddev->hid;
Anssi Hannula
committed
struct usb_device *dev = hid_to_usb_dev(hid);
struct hiddev_collection_info cinfo;
struct hiddev_report_info rinfo;
struct hiddev_field_info finfo;
struct hiddev_devinfo dinfo;
struct hid_report *report;
struct hid_field *field;
struct usbhid_device *usbhid = hid->driver_data;
/* Called without BKL by compat methods so no BKL taken */
/* FIXME: Who or what stop this racing with a disconnect ?? */
if (!hiddev->exist)
return -EIO;
switch (cmd) {
case HIDIOCGVERSION:
return put_user(HID_VERSION, (int __user *)arg);
case HIDIOCAPPLICATION:
if (arg < 0 || arg >= hid->maxapplication)
return -EINVAL;
for (i = 0; i < hid->maxcollection; i++)
if (hid->collection[i].type ==
if (i == hid->maxcollection)
return -EINVAL;
return hid->collection[i].usage;
case HIDIOCGDEVINFO:
dinfo.bustype = BUS_USB;
dinfo.busnum = dev->bus->busnum;
dinfo.devnum = dev->devnum;
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
dinfo.num_applications = hid->maxapplication;
if (copy_to_user(user_arg, &dinfo, sizeof(dinfo)))
return -EFAULT;
return 0;
case HIDIOCGFLAG:
if (put_user(list->flags, (int __user *)arg))
return -EFAULT;
return 0;
case HIDIOCSFLAG:
{
int newflags;
if (get_user(newflags, (int __user *)arg))
return -EFAULT;
if ((newflags & ~HIDDEV_FLAGS) != 0 ||
((newflags & HIDDEV_FLAG_REPORT) != 0 &&
(newflags & HIDDEV_FLAG_UREF) == 0))
return -EINVAL;
list->flags = newflags;
return 0;
}
case HIDIOCGSTRING:
mutex_lock(&hiddev->existancelock);
if (hiddev->exist)
r = hiddev_ioctl_string(hiddev, cmd, user_arg);
else
r = -ENODEV;
mutex_unlock(&hiddev->existancelock);
return r;
mutex_lock(&hiddev->existancelock);
if (!hiddev->exist) {
mutex_unlock(&hiddev->existancelock);
return -ENODEV;
}
mutex_unlock(&hiddev->existancelock);
return 0;
case HIDIOCGREPORT:
if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
return -EFAULT;
if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
return -EINVAL;
if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
return -EINVAL;
mutex_lock(&hiddev->existancelock);
if (hiddev->exist) {
usbhid_submit_report(hid, report, USB_DIR_IN);
usbhid_wait_io(hid);
}
mutex_unlock(&hiddev->existancelock);
return 0;
case HIDIOCSREPORT:
if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
return -EFAULT;
if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
return -EINVAL;
if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
return -EINVAL;
mutex_lock(&hiddev->existancelock);
if (hiddev->exist) {
usbhid_submit_report(hid, report, USB_DIR_OUT);
usbhid_wait_io(hid);
}
mutex_unlock(&hiddev->existancelock);
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
return 0;
case HIDIOCGREPORTINFO:
if (copy_from_user(&rinfo, user_arg, sizeof(rinfo)))
return -EFAULT;
if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
return -EINVAL;
rinfo.num_fields = report->maxfield;
if (copy_to_user(user_arg, &rinfo, sizeof(rinfo)))
return -EFAULT;
return 0;
case HIDIOCGFIELDINFO:
if (copy_from_user(&finfo, user_arg, sizeof(finfo)))
return -EFAULT;
rinfo.report_type = finfo.report_type;
rinfo.report_id = finfo.report_id;
if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
return -EINVAL;
if (finfo.field_index >= report->maxfield)
return -EINVAL;
field = report->field[finfo.field_index];
memset(&finfo, 0, sizeof(finfo));
finfo.report_type = rinfo.report_type;
finfo.report_id = rinfo.report_id;
finfo.field_index = field->report_count - 1;
finfo.maxusage = field->maxusage;
finfo.flags = field->flags;
finfo.physical = field->physical;
finfo.logical = field->logical;
finfo.application = field->application;
finfo.logical_minimum = field->logical_minimum;
finfo.logical_maximum = field->logical_maximum;
finfo.physical_minimum = field->physical_minimum;
finfo.physical_maximum = field->physical_maximum;
finfo.unit_exponent = field->unit_exponent;
finfo.unit = field->unit;
if (copy_to_user(user_arg, &finfo, sizeof(finfo)))
return -EFAULT;
return 0;
case HIDIOCGUCODE:
case HIDIOCGUSAGE:
case HIDIOCSUSAGE:
case HIDIOCGUSAGES:
case HIDIOCSUSAGES:
case HIDIOCGCOLLECTIONINDEX:
mutex_lock(&hiddev->existancelock);
if (hiddev->exist)
r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
else
r = -ENODEV;
mutex_unlock(&hiddev->existancelock);
return r;
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
case HIDIOCGCOLLECTIONINFO:
if (copy_from_user(&cinfo, user_arg, sizeof(cinfo)))
return -EFAULT;
if (cinfo.index >= hid->maxcollection)
return -EINVAL;
cinfo.type = hid->collection[cinfo.index].type;
cinfo.usage = hid->collection[cinfo.index].usage;
cinfo.level = hid->collection[cinfo.index].level;
if (copy_to_user(user_arg, &cinfo, sizeof(cinfo)))
return -EFAULT;
return 0;
default:
if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
return -EINVAL;
if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
int len;
if (!hid->name)
return 0;
len = strlen(hid->name) + 1;
if (len > _IOC_SIZE(cmd))
len = _IOC_SIZE(cmd);
return copy_to_user(user_arg, hid->name, len) ?
-EFAULT : len;
}
if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
int len;
if (!hid->phys)
return 0;
len = strlen(hid->phys) + 1;
if (len > _IOC_SIZE(cmd))
len = _IOC_SIZE(cmd);
return copy_to_user(user_arg, hid->phys, len) ?
-EFAULT : len;
}
}
return -EINVAL;
}
#ifdef CONFIG_COMPAT
static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
static const struct file_operations hiddev_fops = {
.owner = THIS_MODULE,
.read = hiddev_read,
.write = hiddev_write,
.poll = hiddev_poll,
.open = hiddev_open,
.release = hiddev_release,
#ifdef CONFIG_COMPAT
.compat_ioctl = hiddev_compat_ioctl,
#endif
};
static struct usb_class_driver hiddev_class = {
Greg Kroah-Hartman
committed
.name = "hiddev%d",
.minor_base = HIDDEV_MINOR_BASE,
};
/*
* This is where hid.c calls us to connect a hid device to the hiddev driver
*/
int hiddev_connect(struct hid_device *hid, unsigned int force)
struct usbhid_device *usbhid = hid->driver_data;
if (!force) {
unsigned int i;
for (i = 0; i < hid->maxcollection; i++)
if (hid->collection[i].type ==
HID_COLLECTION_APPLICATION &&
!IS_INPUT_APPLICATION(hid->collection[i].usage))
break;
if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
return -1;
init_waitqueue_head(&hiddev->wait);
INIT_LIST_HEAD(&hiddev->list);
spin_lock_init(&hiddev->list_lock);
mutex_init(&hiddev->existancelock);
hid->hiddev = hiddev;
retval = usb_register_dev(usbhid->intf, &hiddev_class);
if (retval) {
err_hid("Not able to get a minor for this device.");
hid->hiddev = NULL;
kfree(hiddev);
return -1;
} else {
hid->minor = usbhid->intf->minor;
hiddev_table[usbhid->intf->minor - HIDDEV_MINOR_BASE] = hiddev;
}
return 0;
}
/*
* This is where hid.c calls us to disconnect a hiddev device from the
* corresponding hid device (usually because the usb device has disconnected)
*/
static struct usb_class_driver hiddev_class;
void hiddev_disconnect(struct hid_device *hid)
{
struct hiddev *hiddev = hid->hiddev;
struct usbhid_device *usbhid = hid->driver_data;
mutex_lock(&hiddev->existancelock);
mutex_unlock(&hiddev->existancelock);
hiddev_table[hiddev->hid->minor - HIDDEV_MINOR_BASE] = NULL;
usb_deregister_dev(usbhid->intf, &hiddev_class);
wake_up_interruptible(&hiddev->wait);
} else {
kfree(hiddev);
}
}
/* Currently this driver is a USB driver. It's not a conventional one in
* the sense that it doesn't probe at the USB level. Instead it waits to
* be connected by HID through the hiddev_connect / hiddev_disconnect
* routines. The reason to register as a USB device is to gain part of the
* minor number space from the USB major.
*
* In theory, should the HID code be generalized to more than one physical
* medium (say, IEEE 1384), this driver will probably need to register its
* own major number, and in doing so, no longer need to register with USB.
* At that point the probe routine and hiddev_driver struct below will no
* longer be useful.
*/
/* We never attach in this manner, and rely on HID to connect us. This
* is why there is no disconnect routine defined in the usb_driver either.
*/
static int hiddev_usbd_probe(struct usb_interface *intf,
const struct usb_device_id *hiddev_info)
{
return -ENODEV;
}
static /* const */ struct usb_driver hiddev_driver = {
.name = "hiddev",
.probe = hiddev_usbd_probe,
};
int __init hiddev_init(void)
{
return usb_register(&hiddev_driver);
}
void hiddev_exit(void)
{
usb_deregister(&hiddev_driver);
}