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// SPDX-License-Identifier: GPL-2.0-only
/*
* arch/arm/common/bL_switcher_dummy_if.c -- b.L switcher dummy interface
*
* Created by: Nicolas Pitre, November 2012
* Copyright: (C) 2012-2013 Linaro Limited
*
* Dummy interface to user space for debugging purpose only.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <linux/uaccess.h>
#include <asm/bL_switcher.h>
static ssize_t bL_switcher_write(struct file *file, const char __user *buf,
size_t len, loff_t *pos)
{
unsigned char val[3];
unsigned int cpu, cluster;
int ret;
pr_debug("%s\n", __func__);
if (len < 3)
return -EINVAL;
if (copy_from_user(val, buf, 3))
return -EFAULT;
/* format: <cpu#>,<cluster#> */
if (val[0] < '0' || val[0] > '9' ||
val[1] != ',' ||
val[2] < '0' || val[2] > '1')
return -EINVAL;
cpu = val[0] - '0';
cluster = val[2] - '0';
ret = bL_switch_request(cpu, cluster);
return ret ? : len;
}
static const struct file_operations bL_switcher_fops = {
.write = bL_switcher_write,
.owner = THIS_MODULE,
};
static struct miscdevice bL_switcher_device = {
MISC_DYNAMIC_MINOR,
"b.L_switcher",
&bL_switcher_fops
};
module_misc_device(bL_switcher_device);
MODULE_AUTHOR("Nicolas Pitre <nico@linaro.org>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("big.LITTLE switcher dummy user interface");
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