rtctime.c

基于s3c44b0的rtc,watchdog,adc,ads的驱动程序

#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/timer.h>
#include <linux/sched.h>
#include <linux/tty.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/miscdevice.h>
#include <linux/delay.h>
#include <linux/types.h>
#include <linux/miscdevice.h>
#include <linux/ioport.h>
#include <linux/mc146818rtc.h>
#include <linux/poll.h>
#include <linux/proc_fs.h>
#include <linux/spinlock.h>
#include <linux/sysctl.h>
#include <linux/pci.h>

#include <asm/mach/irq.h>
#include <asm/hardware.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/arch/io.h>
#include "44b.h"

#define DEVICE_NAME	"rtctime"

typedef struct {
	int  year;
	int  month;
	int  day;
	int  weekday;
	int  hour;
	int  min;
	int  sec;
}RTCSTATE;

static RTCSTATE _time;

void Display_RTC(void);
void Set_year(int);
void Set_mon(int);
void Set_day(int);
void Set_weekday(int);
void Set_hour(int);
void Set_min(int);

void Display_RTC(void)	//显示当前时间(只需从寄存器中读取数值即可)
{
    rRTCCON = 0x01;
 
    _time.year = rBCDYEAR;
    _time.month=rBCDMON;
    _time.day=rBCDDAY;
    _time.weekday=rBCDDATE;
    _time.hour=rBCDHOUR;
    _time.min=rBCDMIN;
    _time.sec=rBCDSEC;
    if(_time.sec==0)	//秒数到零时,重新读一下其它寄存器,为了防止一秒误差
    {
	_time.year = rBCDYEAR;
    	_time.month=rBCDMON;
    	_time.day=rBCDDAY;
    	_time.weekday=rBCDDATE;
    	_time.hour=rBCDHOUR;
    	_time.min=rBCDMIN;
    }

    //printk("\n%4d-%02x-%02x-%x-%02x:%02x:%02x\n",_time.year+2000,_time.month,_time.day,_time.weekday,_time.hour,_time.min,_time.sec);	 
    rRTCCON = 0x0;    
}
void Set_year(int year)	//设置年
{
    rRTCCON = 0x01;
 
    rBCDYEAR = ((year/10)<<4) + (year%10);

    rRTCCON = 0x0;    
}
void Set_mon(int mon)	//设置月
{
    rRTCCON = 0x01;
 
    rBCDMON = ((mon/10)<<4) + (mon%10);

    rRTCCON = 0x0;    
}
void Set_day(int day)	//设置日
{
    rRTCCON = 0x01;
 
    rBCDDAY = ((day/10)<<4) + (day%10);

    rRTCCON = 0x0;    
}
void Set_weekday(int weekday)	//设置星期
{
    rRTCCON = 0x01;
 
    rBCDDATE = ((weekday/10)<<4) + (weekday%10);

    rRTCCON = 0x0;    
}
void Set_hour(int hour)	//设置小时
{
    rRTCCON = 0x01;
 
    rBCDHOUR = ((hour/10)<<4) + (hour%10);

    rRTCCON = 0x0;    
}
void Set_min(int min)	//设置分钟
{
    rRTCCON = 0x01;
 
    rBCDMIN = ((min/10)<<4) + (min%10);

    rRTCCON = 0x0;    
}
static int rtctime_open(struct inode *inode, struct file *filp)
{
	return 0;
}

static int rtctime_release(struct inode *inode, struct file *filp)
{
  	return 0;
}
static int rtctime_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
{
	switch(cmd) 
	{
		case 0:
			Display_RTC();
			return 0;
		case 1:
			Set_year(arg);
			return 0;
		case 2:
			Set_mon(arg);
			return 0;
		case 3:
			Set_day(arg);
			return 0;
		case 4:
			Set_weekday(arg);
			return 0;
		case 5:
			Set_hour(arg);
			return 0;
		case 6:
			Set_min(arg);
			return 0;
        	default:
                        printk("ERROR\n");
    	}
    	return 0;
}
static int rtctime_read(struct file *fp, char *buf, size_t count)
{
    put_user(_time.year, buf);	//将寄存器数值存入缓冲区,以便上层read函数调用
    put_user(_time.month, buf+4);
    put_user(_time.day, buf+8);
    put_user(_time.weekday, buf+12);
    put_user(_time.hour, buf+16);
    put_user(_time.min, buf+20);
    put_user(_time.sec, buf+24);

    return count;
}
static struct file_operations rtctime_fops = {
  	open:	rtctime_open,
	ioctl:	rtctime_ioctl,
  	release:	rtctime_release,
	read:	rtctime_read,
};
int rtctime_init(void)
{
	int ret;

	ret = register_chrdev(254, DEVICE_NAME, &rtctime_fops);
	if (ret < 0) {
		printk(DEVICE_NAME " can't get major number\n");
		return ret;
	}
	else 
		printk("OK\n");	

	return 0;
}