Mini example with KBUS again.
/******************************************************************************
*
* $Id$
*
* Copyright (C) 2006 Florian Pose, Ingenieurgemeinschaft IgH
*
* This file is part of the IgH EtherCAT Master.
*
* The IgH EtherCAT Master 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.
*
* The IgH EtherCAT Master 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 the IgH EtherCAT Master; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* The right to use EtherCAT Technology is granted and comes free of
* charge under condition of compatibility of product made by
* Licensee. People intending to distribute/sell products based on the
* code, have to sign an agreement to guarantee that products using
* software based on IgH EtherCAT master stay compatible with the actual
* EtherCAT specification (which are released themselves as an open
* standard) as the (only) precondition to have the right to use EtherCAT
* Technology, IP and trade marks.
*
*****************************************************************************/
/**
\file
EtherCAT XML device.
*/
/*****************************************************************************/
#include <linux/module.h>
#include "master.h"
#include "xmldev.h"
/*****************************************************************************/
static char *test_str = "hello world!\n";
int ecxmldev_open(struct inode *, struct file *);
int ecxmldev_release(struct inode *, struct file *);
ssize_t ecxmldev_read(struct file *, char __user *, size_t, loff_t *);
ssize_t ecxmldev_write(struct file *, const char __user *, size_t, loff_t *);
/*****************************************************************************/
static struct file_operations fops = {
.owner = THIS_MODULE,
.open = ecxmldev_open,
.release = ecxmldev_release,
.read = ecxmldev_read,
.write = ecxmldev_write
};
/*****************************************************************************/
/**
XML device constructor.
\return 0 in case of success, else < 0
*/
int ec_xmldev_init(ec_xmldev_t *xmldev, /**< EtherCAT XML device */
ec_master_t *master, /**< EtherCAT master */
dev_t dev_num /**< device number */
)
{
atomic_set(&xmldev->available, 1);
cdev_init(&xmldev->cdev, &fops);
xmldev->cdev.owner = THIS_MODULE;
if (cdev_add(&xmldev->cdev,
MKDEV(MAJOR(dev_num), master->index), 1)) {
EC_ERR("Failed to add character device!\n");
return -1;
}
return 0;
}
/*****************************************************************************/
/**
XML device destructor.
*/
void ec_xmldev_clear(ec_xmldev_t *xmldev /**< EtherCAT XML device */)
{
cdev_del(&xmldev->cdev);
}
/*****************************************************************************/
int ec_xmldev_request(ec_xmldev_t *xmldev,
uint32_t vendor_id,
uint32_t product_code
)
{
return 1;
}
/******************************************************************************
* file_operations
*****************************************************************************/
int ecxmldev_open(struct inode *inode, struct file *filp)
{
ec_xmldev_t *xmldev;
xmldev = container_of(inode->i_cdev, ec_xmldev_t, cdev);
if (!atomic_dec_and_test(&xmldev->available)) {
atomic_inc(&xmldev->available);
return -EBUSY;
}
filp->private_data = xmldev;
EC_DBG("File opened.\n");
return 0;
}
/*****************************************************************************/
int ecxmldev_release(struct inode *inode, struct file *filp)
{
ec_xmldev_t *xmldev = container_of(inode->i_cdev, ec_xmldev_t, cdev);
atomic_inc(&xmldev->available);
EC_DBG("File closed.\n");
return 0;
}
/*****************************************************************************/
ssize_t ecxmldev_read(struct file *filp, char __user *buf,
size_t count, loff_t *f_pos)
{
size_t len = strlen(test_str);
if (*f_pos >= len) return 0;
if (*f_pos + count > len) count = len - *f_pos;
if (copy_to_user(buf, test_str + *f_pos, count)) return -EFAULT;
*f_pos += count;
return count;
}
/*****************************************************************************/
ssize_t ecxmldev_write(struct file *filp,
const char __user *buf,
size_t count,
loff_t *f_pos)
{
return -EFAULT;
}
/*****************************************************************************/