sbc2410_leds.c

我修改sbc2410开发板的例子成功运行的s3c2410的字符驱动。

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/errno.h> 	
#include <linux/ioport.h>	
#include <linux/init.h>		
#include <asm/uaccess.h>  
#include <asm/io.h>  	    
#include <asm-arm/arch-s3c2410/S3C2410.h>
#include "drv.h"

#define 	BUF_LEN 		4
#define 	DEVICE_NAME 	"cyc_io"

static int  Device_Open = 0;

volatile unsigned long *led_addr;	
volatile unsigned long *led_con;
volatile unsigned long *led_up;

int device_ioctl(struct inode *,struct file *,unsigned int ,unsigned long ); 	

static int device_open(struct inode *inode, struct file *file)
{
	led_addr = ioremap(0x56000014,4);	
	led_con = ioremap(0x56000010,4);
	led_up = ioremap(0x56000018,4);

	*led_con = 0X15400;
	*led_up = 0;
	printk("the address of led_addr is: 0x%p\n",led_addr);		
	printk("Device Open!\n");		
	if (Device_Open) return -EBUSY;	
	Device_Open++;
	return 0;
}

static int device_release(struct inode *inode, struct file *file)
{
	printk(("Device released\n"));
	Device_Open --;		
	iounmap( (void *)led_addr);	
	return 0;
}

int device_ioctl(struct inode *inode, struct file *file, unsigned int ioctl_num, unsigned long ioctl_param)	
{
	int *data;
	printk(("Device_\n"));
	switch(ioctl_num) 
	{
		case IOCTL_SET_MSG:		data = (int *)ioctl_param;	
  								printk("Device ioctl SET_MSG %d\n",*data );
								*led_addr =~ ((*data)<<7);//输出到led灯
								break;
		case IOCTL_GET_MSG:		printk(("Device_ioctl PUT_MSG\n"));
								break;
	}
	return 0;
};

struct file_operations Fops = {
	.open 		= device_open,
	.release 		= device_release,
	.ioctl		= device_ioctl
	};

static int __init led_module_init( void )
{
	int ret_val;

	ret_val = register_chrdev(MAJOR_NUM, DEVICE_NAME, &Fops);

	if (ret_val < 0) 
	{
    		printk ("%s failed with %d\n",  "Sorry, registering the character device ",  ret_val);
    		return ret_val;
	}
  
	printk ("%s The major device number is %d.\n",  "Registeration is a success", MAJOR_NUM);
  	printk ("If you want to talk to the device driver,\n");
  	printk ("you'll have to create a device file. \n");
  	printk ("We suggest you use:\n");
  	printk ("mknod /dev/%s c %d 0\n", DEVICE_FILE_NAME,MAJOR_NUM);
  	printk ("The device file name is important, because\n");
  	printk ("the ioctl program assumes that's the\n");
  	printk ("file you'll use.\n");
	return 0;
};

static void __exit led_module_cleanup(void)
{
	int ret;

	ret = unregister_chrdev(MAJOR_NUM, DEVICE_NAME);
 	if (ret < 0)
		printk("Error in module_unregister_chrdev: %d\n", ret);
	else
		printk("Close the char device OK!\n");
};

module_init(led_module_init);		
module_exit(led_module_cleanup);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Cvtech Co., Ltd <http://www.cvtech.com.cn>");
MODULE_DESCRIPTION("LED char driver");