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/*
* Copyright (c) 2011 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* 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
* MA 02111-1307 USA
*/
#include <common.h>
#include <init.h>
static ssize_t zero_read(struct cdev *cdev, void *buf, size_t count, loff_t offset, ulong flags)
{
memset(buf, 0, count);
return count;
}
static struct file_operations zeroops = {
.read = zero_read,
.lseek = dev_lseek_default,
};
static int zero_init(void)
{
struct cdev *cdev;
cdev = xzalloc(sizeof (*cdev));
cdev->name = "zero";
cdev->flags = DEVFS_IS_CHARACTER_DEV;
cdev->ops = &zeroops;
devfs_create(cdev);
return 0;
}
device_initcall(zero_init);
static ssize_t full_read(struct cdev *cdev, void *buf, size_t count, loff_t offset, ulong flags)
{
memset(buf, 0xff, count);
return count;
}
static struct file_operations fullops = {
.read = full_read,
.lseek = dev_lseek_default,
};
static int full_init(void)
{
struct cdev *cdev;
cdev = xzalloc(sizeof (*cdev));
cdev->name = "full";
cdev->flags = DEVFS_IS_CHARACTER_DEV;
cdev->ops = &fullops;
devfs_create(cdev);
return 0;
}
device_initcall(full_init);
static ssize_t null_write(struct cdev *cdev, const void *buf, size_t count, loff_t offset, ulong flags)
{
return count;
}
static struct file_operations nullops = {
.write = null_write,
.lseek = dev_lseek_default,
};
static int null_init(void)
{
struct cdev *cdev;
cdev = xzalloc(sizeof (*cdev));
cdev->name = "null";
cdev->flags = DEVFS_IS_CHARACTER_DEV;
cdev->ops = &nullops;
devfs_create(cdev);
return 0;
}
device_initcall(null_init);
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