openwrt/target/linux/rb1xx-2.6/files/drivers/char/adm5120_gpio.c

59 lines
1.2 KiB
C

/*
* ADM5120 LED (GPIO) driver
*
* Copyright (C) Jeroen Vreeken (pe1rxq@amsat.org), 2005
*/
#include <linux/autoconf.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/miscdevice.h>
#include <linux/fs.h>
#define LED_MINOR 151
#define GPIO_IO ((unsigned long *)0xb20000b8)
static ssize_t adm5120_led_write(struct file *file, const char __user *data,
size_t len, loff_t *ppos)
{
unsigned char val;
if (!len || get_user(val, data))
return -EFAULT;
*GPIO_IO=(*GPIO_IO & 0x00ffffff) | (val<<24);
return 1;
}
static struct file_operations adm5120_led_fops = {
.owner = THIS_MODULE,
.write = adm5120_led_write,
};
static struct miscdevice adm5120_led_device = {
LED_MINOR,
"led",
&adm5120_led_fops,
};
static int __init adm5120_led_init(void)
{
printk(KERN_INFO "ADM5120 LED & GPIO driver\n");
if (misc_register(&adm5120_led_device)) {
printk(KERN_WARNING "Couldn't register device %d\n", LED_MINOR);
return -EBUSY;
}
return 0;
}
static void __exit adm5120_led_exit(void)
{
misc_deregister(&adm5120_led_device);
}
module_init(adm5120_led_init);
module_exit(adm5120_led_exit);
MODULE_DESCRIPTION("ADM5120 LED and GPIO driver");
MODULE_AUTHOR("Jeroen Vreeken");
MODULE_LICENSE("GPL");