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/*
* drivers.c
* (C) Copyright 1999 Randy Dunlap.
* (C) Copyright 1999, 2000 Thomas Sailer <sailer@ife.ee.ethz.ch>. (proc file per device)
* (C) Copyright 1999 Deti Fliegl (new USB architecture)
*
* $id$
*
* 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
*
*************************************************************
*
* 1999-12-16: Thomas Sailer <sailer@ife.ee.ethz.ch>
* Converted the whole proc stuff to real
* read methods. Now not the whole device list needs to fit
* into one page, only the device list for one bus.
* Added a poll method to /proc/bus/usb/devices, to wake
* up an eventual usbd
* 2000-01-04: Thomas Sailer <sailer@ife.ee.ethz.ch>
* Turned into its own filesystem
*
* $Id: drivers.c,v 1.3 2000/01/11 13:58:24 tom Exp $
*/
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/usb.h>
#include <linux/usbdevice_fs.h>
#include <asm/uaccess.h>
/*****************************************************************/
/*
* Dump usb_driver_list.
*
* We now walk the list of registered USB drivers.
*/
static ssize_t usb_driver_read(struct file *file, char *buf, size_t nbytes, loff_t *ppos)
{
struct list_head *tmp = usb_driver_list.next;
char *page, *start, *end;
ssize_t ret = 0;
unsigned int pos, len;
if (*ppos < 0)
return -EINVAL;
if (nbytes <= 0)
return 0;
if (!access_ok(VERIFY_WRITE, buf, nbytes))
return -EFAULT;
if (!(page = (char*) __get_free_page(GFP_KERNEL)))
return -ENOMEM;
start = page;
end = page + (PAGE_SIZE - 100);
pos = *ppos;
for (; tmp != &usb_driver_list; tmp = tmp->next) {
struct usb_driver *driver = list_entry(tmp, struct usb_driver, driver_list);
int minor = driver->fops ? driver->minor : -1;
if (minor == -1)
start += sprintf (start, " %s\n", driver->name);
else
start += sprintf (start, "%3d-%3d: %s\n", minor, minor + 15, driver->name);
if (start > end) {
start += sprintf(start, "(truncated)\n");
break;
}
}
if (start == page)
start += sprintf(start, "(none)\n");
len = start - page;
if (len > pos) {
len -= pos;
if (len > nbytes)
len = nbytes;
ret = len;
if (copy_to_user(buf, page + pos, len))
ret = -EFAULT;
else
*ppos += len;
}
free_page((unsigned long)page);
return ret;
}
static loff_t usb_driver_lseek(struct file * file, loff_t offset, int orig)
{
switch (orig) {
case 0:
file->f_pos = offset;
return file->f_pos;
case 1:
file->f_pos += offset;
return file->f_pos;
case 2:
return -EINVAL;
default:
return -EINVAL;
}
}
struct file_operations usbdevfs_drivers_fops = {
llseek: usb_driver_lseek,
read: usb_driver_read,
};
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