dacdev.c

S3C2410 DAC驱动程序

/*下面是一个简单的gpio跑马灯驱动,基于FS2410处理器:*/
#ifndef __KERNEL__ 
#define __KERNEL__ 
#endif 
#ifndef MODULE 
#define MODULE 
#endif 

#include <linux/fs.h>   
//#include <linux/iobuf.h> 
#include <linux/major.h> 
#include <asm/uaccess.h> 
#include <asm/hardware.h> 
#include <asm/arch-s3c2410/regs-gpio.h> 
#include <asm/io.h> 
#include <linux/vmalloc.h> 
#include <linux/config.h> 
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>  
#include <linux/delay.h>
#include <linux/cdev.h>
//#include "dac0832.h"

MODULE_LICENSE("GPL");
#define DAC_MAJOR 226  

struct DAC_dev *DAC_devices;
static int dac_ctl_open(struct inode*, struct file*);              
static int dac_ctl_ioctl(struct inode*, struct file*, unsigned int,unsigned long);
int dcon1,dcon2;
static void *myadd;
static void *DAC;
static struct file_operations dac_ctl_fops={
        .ioctl = dac_ctl_ioctl,
        .open = dac_ctl_open,
};  

static int dac_ctl_open(struct inode *inode,struct file *fllp)
{	

        printk("open dac devices\n");
        return 0;
}

static int dac_ctl_ioctl(struct inode *inode,struct file *flip,unsigned int command,unsigned long arg)
{
	if(command==1)
	{
	dcon1=(arg<<8);
	printk("dac1=0x%x\n",dcon1);
	__raw_writel(dcon1, DAC);
	mdelay(1); 

	__raw_writel(0x7400, myadd);//dacs1:0111
	mdelay(10); 
	__raw_writel(0x5400, myadd);//dacs1:0101
	mdelay(80); 
	__raw_writel(0x7400, myadd);//dacs1:0111
	mdelay(10); 
	__raw_writel(0x0f400, myadd); 
	
	}
	if(command==2)
	{
        dcon2=(arg<<8);
	printk("dac2=0x%x\n",dcon2);
	__raw_writel(dcon2, DAC);
	mdelay(1); 
	__raw_writel(0x0b400, myadd);//dacs2:1011
	mdelay(10); 
	__raw_writel(0x9400, myadd); //dacs2:1001
	mdelay(80); 
	__raw_writel(0x0b400, myadd); //dacs2:1011
	mdelay(10); 
	__raw_writel(0x0f400, myadd); 
	
	}
      

//cc2:          
		//dac_opt(dcon1,dcon2);
	     return 1;
}
//////////////////////////////////////////////////////////////////////
void __exit dac_release(void)
{
    printk("quit dac\n");
    unregister_chrdev(DAC_MAJOR, "dac"); 
}
/////////////////////////////////////////////////////////////////////
static int __init dac_init(void) 
{

        int ret;
	dcon1=0xc000;
	dcon1=0xc000;
	myadd=ioremap(0x3900f0e8,0x04);
	DAC=ioremap(0x3900f0ec,0x04);
        printk("dac_init\n");
        ret = register_chrdev(DAC_MAJOR, "dac", &dac_ctl_fops);
        if(ret < 0)
        {
                printk("fail to register\n");
                return -1;
        }
        printk("success to register\n");
        return 0;
}

module_init(dac_init);           
module_exit(dac_release);