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/*
* 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>
*/
#define HIDDEV_MINOR_BASE 96
#define HIDDEV_MINORS 16
#define HIDDEV_BUFFER_SIZE 64
#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>
#include "hid.h"
#include <linux/hiddev.h>
struct hiddev {
int exist;
int open;
int minor;
wait_queue_head_t wait;
devfs_handle_t devfs;
struct hid_device *hid;
struct hiddev_list *list;
};
struct hiddev_list {
struct hiddev_event buffer[HIDDEV_BUFFER_SIZE];
int head;
int tail;
struct fasync_struct *fasync;
struct hiddev *hiddev;
struct hiddev_list *next;
};
static struct hiddev *hiddev_table[HIDDEV_MINORS];
static devfs_handle_t hiddev_devfs_handle;
/*
* 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)
{
struct hid_report_enum *report_enum;
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);
if ((rinfo->report_id & ~HID_REPORT_ID_MASK) != 0) {
switch (rinfo->report_id & ~HID_REPORT_ID_MASK) {
case HID_REPORT_ID_FIRST:
list = report_enum->report_list.next;
if (list == &report_enum->report_list) return NULL;
rinfo->report_id = ((struct hid_report *) list)->id;
break;
case HID_REPORT_ID_NEXT:
list = (struct list_head *)
report_enum->report_id_hash[rinfo->report_id &
HID_REPORT_ID_MASK];
if (list == NULL) return NULL;
list = list->next;
if (list == &report_enum->report_list) return NULL;
rinfo->report_id = ((struct hid_report *) list)->id;
break;
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 list_head *list;
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 = report_enum->report_list.next;
while (list != &report_enum->report_list) {
report = (struct hid_report *) 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;
}
}
}
list = list->next;
}
return NULL;
}
/*
* 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, unsigned int usage, int value)
{
struct hiddev *hiddev = hid->hiddev;
struct hiddev_list *list = hiddev->list;
while (list) {
list->buffer[list->head].hid = usage;
list->buffer[list->head].value = value;
list->head = (list->head + 1) & (HIDDEV_BUFFER_SIZE - 1);
kill_fasync(&list->fasync, SIGIO, POLL_IN);
list = list->next;
}
wake_up_interruptible(&hiddev->wait);
}
/*
* fasync file op
*/
static int hiddev_fasync(int fd, struct file *file, int on)
{
int retval;
struct hiddev_list *list = file->private_data;
retval = fasync_helper(fd, file, on, &list->fasync);
return retval < 0 ? retval : 0;
}
/*
* De-allocate a hiddev structure
*/
static void hiddev_cleanup(struct hiddev *hiddev)
{
devfs_unregister(hiddev->devfs);
hiddev_table[hiddev->minor] = NULL;
kfree(hiddev);
}
/*
* release file op
*/
static int hiddev_release(struct inode * inode, struct file * file)
{
struct hiddev_list *list = file->private_data;
struct hiddev_list **listptr;
lock_kernel();
listptr = &list->hiddev->list;
hiddev_fasync(-1, file, 0);
while (*listptr && (*listptr != list))
listptr = &((*listptr)->next);
*listptr = (*listptr)->next;
if (!--list->hiddev->open) {
if (list->hiddev->exist)
hid_close(list->hiddev->hid);
else
hiddev_cleanup(list->hiddev);
}
kfree(list);
unlock_kernel();
return 0;
}
/*
* open file op
*/
static int hiddev_open(struct inode * inode, struct file * file) {
struct hiddev_list *list;
int i = MINOR(inode->i_rdev) - HIDDEV_MINOR_BASE;
if (i >= HIDDEV_MINORS || !hiddev_table[i])
return -ENODEV;
if (!(list = kmalloc(sizeof(struct hiddev_list), GFP_KERNEL)))
return -ENOMEM;
memset(list, 0, sizeof(struct hiddev_list));
list->hiddev = hiddev_table[i];
list->next = hiddev_table[i]->list;
hiddev_table[i]->list = list;
file->private_data = list;
if (!list->hiddev->open++)
if (list->hiddev->exist)
hid_open(hiddev_table[i]->hid);
return 0;
}
/*
* "write" file op
*/
static ssize_t hiddev_write(struct file * file, const char * buffer,
size_t count, loff_t *ppos)
{
return -EINVAL;
}
/*
* "read" file op
*/
static ssize_t hiddev_read(struct file * file, char * buffer, size_t count,
loff_t *ppos)
{
DECLARE_WAITQUEUE(wait, current);
struct hiddev_list *list = file->private_data;
int retval = 0;
if (list->head == list->tail) {
add_wait_queue(&list->hiddev->wait, &wait);
set_current_state(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;
}
schedule();
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&list->hiddev->wait, &wait);
}
if (retval)
return retval;
while (list->head != list->tail && retval + sizeof(struct hiddev_event) <= count) {
if (copy_to_user(buffer + retval, list->buffer + list->tail,
sizeof(struct hiddev_event))) return -EFAULT;
list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
retval += sizeof(struct hiddev_event);
}
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;
}
#define GET_TIMEOUT 3
#define SET_TIMEOUT 3
/*
* "ioctl" file op
*/
static int hiddev_ioctl(struct inode *inode, 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;
struct usb_device *dev = hid->dev;
struct hiddev_report_info rinfo;
struct hiddev_usage_ref uref;
struct hid_report *report;
struct hid_field *field;
if (!hiddev->exist) return -EIO;
switch (cmd) {
case HIDIOCGVERSION:
return put_user(HID_VERSION, (int *) arg);
case HIDIOCAPPLICATION:
if (arg < 0 || arg >= hid->maxapplication)
return -EINVAL;
return hid->application[arg];
case HIDIOCGDEVINFO:
{
struct hiddev_devinfo dinfo;
dinfo.bustype = BUS_USB;
dinfo.busnum = dev->bus->busnum;
dinfo.devnum = dev->devnum;
dinfo.ifnum = hid->ifnum;
dinfo.vendor = dev->descriptor.idVendor;
dinfo.product = dev->descriptor.idProduct;
dinfo.version = dev->descriptor.bcdDevice;
dinfo.num_applications = hid->maxapplication;
return copy_to_user((void *) arg, &dinfo, sizeof(dinfo));
}
case HIDIOCGSTRING:
{
int idx, len;
char *buf;
if (get_user(idx, (int *) 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((void *) (arg+sizeof(int)), buf, len+1)) {
kfree(buf);
return -EFAULT;
}
kfree(buf);
return len;
}
case HIDIOCINITREPORT:
hid_init_reports(hid);
return 0;
case HIDIOCGREPORT:
if (copy_from_user(&rinfo, (void *) 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;
hid_read_report(hid, report);
return 0;
case HIDIOCSREPORT:
if (copy_from_user(&rinfo, (void *) 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;
hid_write_report(hid, report);
return 0;
case HIDIOCGREPORTINFO:
if (copy_from_user(&rinfo, (void *) arg, sizeof(rinfo)))
return -EFAULT;
if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
return -EINVAL;
rinfo.num_fields = report->maxfield;
return copy_to_user((void *) arg, &rinfo, sizeof(rinfo));
case HIDIOCGFIELDINFO:
{
struct hiddev_field_info finfo;
if (copy_from_user(&finfo, (void *) 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;
return copy_to_user((void *) arg, &finfo, sizeof(finfo));
}
case HIDIOCGUCODE:
if (copy_from_user(&uref, (void *) arg, sizeof(uref)))
return -EFAULT;
rinfo.report_type = uref.report_type;
rinfo.report_id = uref.report_id;
if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
return -EINVAL;
if (uref.field_index >= report->maxfield)
return -EINVAL;
field = report->field[uref.field_index];
if (uref.usage_index >= field->maxusage)
return -EINVAL;
uref.usage_code = field->usage[uref.usage_index].hid;
return copy_to_user((void *) arg, &uref, sizeof(uref));
case HIDIOCGUSAGE:
if (copy_from_user(&uref, (void *) arg, sizeof(uref)))
return -EFAULT;
if (uref.report_id == HID_REPORT_ID_UNKNOWN) {
field = hiddev_lookup_usage(hid, &uref);
if (field == NULL)
return -EINVAL;
} else {
rinfo.report_type = uref.report_type;
rinfo.report_id = uref.report_id;
if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
return -EINVAL;
if (uref.field_index >= report->maxfield)
return -EINVAL;
field = report->field[uref.field_index];
if (uref.usage_index >= field->maxusage)
return -EINVAL;
}
uref.value = field->value[uref.usage_index];
return copy_to_user((void *) arg, &uref, sizeof(uref));
case HIDIOCSUSAGE:
if (copy_from_user(&uref, (void *) arg, sizeof(uref)))
return -EFAULT;
if (uref.report_type == HID_REPORT_TYPE_INPUT)
return -EINVAL;
if (uref.report_id == HID_REPORT_ID_UNKNOWN) {
field = hiddev_lookup_usage(hid, &uref);
if (field == NULL)
return -EINVAL;
} else {
rinfo.report_type = uref.report_type;
rinfo.report_id = uref.report_id;
if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
return -EINVAL;
if (uref.field_index >= report->maxfield)
return -EINVAL;
field = report->field[uref.field_index];
if (uref.usage_index >= field->maxusage)
return -EINVAL;
}
field->value[uref.usage_index] = uref.value;
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((char *) arg, hid->name, len) ?
-EFAULT : len;
}
}
return -EINVAL;
}
static struct file_operations hiddev_fops = {
owner: THIS_MODULE,
read: hiddev_read,
write: hiddev_write,
poll: hiddev_poll,
open: hiddev_open,
release: hiddev_release,
ioctl: hiddev_ioctl,
fasync: hiddev_fasync,
};
/*
* This is where hid.c calls us to connect a hid device to the hiddev driver
*/
int hiddev_connect(struct hid_device *hid)
{
struct hiddev *hiddev;
int minor, i;
char devfs_name[16];
for (i = 0; i < hid->maxapplication; i++)
if (!IS_INPUT_APPLICATION(hid->application[i]))
break;
if (i == hid->maxapplication)
return -1;
for (minor = 0; minor < HIDDEV_MINORS && hiddev_table[minor]; minor++);
if (minor == HIDDEV_MINORS) {
printk(KERN_ERR "hiddev: no more free hiddev devices\n");
return -1;
}
if (!(hiddev = kmalloc(sizeof(struct hiddev), GFP_KERNEL)))
return -1;
memset(hiddev, 0, sizeof(struct hiddev));
init_waitqueue_head(&hiddev->wait);
hiddev->minor = minor;
hiddev_table[minor] = hiddev;
hiddev->hid = hid;
hiddev->exist = 1;
sprintf(devfs_name, "hiddev%d", minor);
hiddev->devfs = devfs_register(hiddev_devfs_handle, devfs_name,
DEVFS_FL_DEFAULT, USB_MAJOR,
minor + HIDDEV_MINOR_BASE,
S_IFCHR | S_IRUGO | S_IWUSR,
&hiddev_fops, NULL);
hid->minor = minor;
hid->hiddev = 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)
*/
void hiddev_disconnect(struct hid_device *hid)
{
struct hiddev *hiddev = hid->hiddev;
hiddev->exist = 0;
if (hiddev->open) {
hid_close(hiddev->hid);
wake_up_interruptible(&hiddev->wait);
} else {
hiddev_cleanup(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 void *hiddev_usbd_probe(struct usb_device *dev, unsigned int ifnum,
const struct usb_device_id *hiddev_info)
{
return NULL;
}
static /* const */ struct usb_driver hiddev_driver = {
name: "hiddev",
probe: hiddev_usbd_probe,
fops: &hiddev_fops,
minor: HIDDEV_MINOR_BASE
};
int __init hiddev_init(void)
{
hiddev_devfs_handle =
devfs_mk_dir(devfs_find_handle(NULL, "usb", 0, 0, 0, 0), "hid", NULL);
usb_register(&hiddev_driver);
return 0;
}
void __exit hiddev_exit(void)
{
devfs_unregister(hiddev_devfs_handle);
usb_deregister(&hiddev_driver);
}
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