dac0832.c

Linux下基于EP7312

#include <linux/config.h>
#include <linux/utsname.h>
#include <linux/kernel.h>
#include <linux/major.h>
#include <linux/string.h>
#include <linux/fcntl.h>
#include <linux/malloc.h>
#include <linux/timer.h>
#include <linux/init.h>
#include <asm/irq.h>
#include <asm/io.h>

#  define copy_to_user(t,f,n)         (memcpy_tofs(t,f,n), 0)

#define Dac0832Major 	57 

static short Ready;

static void CloseDac0832(struct inode * inode, struct file * file)
{

	//close interrupt
	printk("dac0832 is closed\n");
	return ;
}

static int OpenDac0832(struct inode * inode, struct file * file)
{
	Ready = 0;

	printk("dac0832 is open\n");
	
	*(volatile unsigned char *)0xff000000 = 0x00;
	
	return 0;
}

/*
 * read mouse data.  Currently never blocks.
 */
static int ReadDac0832(struct file * file, char * buf, size_t count, loff_t *ppos)
{
	return 0;
}
static int Dac0832Ioctl(
	struct inode *inode, 
	struct file * file, 
	unsigned int cmd, 
	unsigned long arg)

{
        int i;
	
//	printk("enter ioctl.........\n");

        switch(cmd) {
		case 0:
			{
			unsigned char ch = *(unsigned char *)arg;
			long val = 0x00000000;
		
			val |= ch;
			val |= ch << 8;
			val |= ch << 16;
			val |= ch << 24;
			
			
			*(volatile unsigned long *)0xf6000000 = val; 
			*(volatile unsigned long *)0xf6000000 = val; 
			for(i = 0; i < 10000; i++);

			return 1;
			
			}
                case 1:
                        i = ReadDac0832(file, (char *)arg, 1, 0);
                        return i;
                default:
                        return -EINVAL;
        }
        return 1;
}

static struct file_operations Dac0832fops = {
	read:	ReadDac0832,     /* read */
	ioctl:	Dac0832Ioctl,           /* ioctl */
	open:	OpenDac0832,    /* just a selector for the real open */
	release:	CloseDac0832,           /* release */
};

int dac0832_init(void)
{
        int     rc;


        rc = register_chrdev(Dac0832Major, "dac0832", &Dac0832fops);
        if (rc < 0) {
		printk(KERN_WARNING "Dac0832: can't get Major %d\n", Dac0832Major);
		return rc;
            }
	
	*(unsigned long *)0xff000180 |= 0x00120000;
	
	*(unsigned long *)0xf6000000 = 0x80808080;
	*(unsigned long *)0xf6000000 = 0x80808080;
	
	printk("dac0832------------support.\n");
	return 0;
}

void dac0832_cleanup(void)
{
	
	 unregister_chrdev(Dac0832Major, "dac0832");
  	 return;
}


module_init(dac0832_init);
module_exit(dac0832_cleanup);