#include <linux/miscdevice.h>

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

#define DEVICE_NAME "led1"

unsigned long GPIOK_VA_BASE ;

#define GPIOK_CON0  GPIOK_VA_BASE 

#define GPIOK_CON1  GPIOK_VA_BASE+0X4

#define GPIOK_DAT   GPIOK_VA_BASE+ 0X8

#define GPIOK_PUD   GPIOK_VA_BASE +0XC

#define GPIOK_PA_BASE 0X7F008800

struct resource led_resource = {

.name  = "led io-mem ",

.start  = GPIOK_PA_BASE,

.end = GPIOK_PA_BASE +0X10,

.flags = IORESOURCE_MEM,

};

static void led_pin_setup(void)

{

unsigned long start = led_resource.start;

unsigned long size = led_resource.end - led_resource.start;

unsigned long tmp;

request_mem_region(start,size,led_resource.name);

GPIOK_VA_BASE = (unsigned long)ioremap(start,size);

printk ("<1> [GPIOK_VA_BASE = 0x%lx]n", GPIOK_VA_BASE);

tmp = readl(GPIOK_CON0);

tmp = (tmp & ~(0xffffu<<16))|(0x1111u<<16);

writel(tmp,GPIOK_CON0);

tmp = readl(GPIOK_DAT);

tmp |= (0xf <<4);

writel(tmp,GPIOK_DAT);

}

static void led_pin_release(void)

{

iounmap((void*)GPIOK_VA_BASE);

release_mem_region(led_resource.start,led_resource.end - led_resource.start);

}

static unsigned long led_getdata(void)

{

return ((readl(GPIOK_DAT)>>4)& 0XF);

}

static void led_setdata(int data)

{

unsigned long temp;

temp = readl(GPIOK_DAT);

temp = ~(0xF<<4) | ((data&0xF)<<4);

writel(temp,GPIOK_DAT);

}

static ssize_t led_read(struct file *filp, char __user *buf, size_t size, loff_t *ppos)

{

int ret = 0;

char buffer[1];

memset(buffer,0,sizeof(buffer));

buffer[0] = (char)led_getdata() ;

if(copy_to_user(buf,buffer,size))

{

ret = -EFAULT;

}

return size;

}

static ssize_t led_write(struct file *flip,const char __user *buf,size_t size,loff_t *ppos)

{

int ret = 0;

unsigned long buffer[1];

memset(buffer,0,sizeof(buffer));

if(copy_from_user(buffer,buf,size))

{

printk("errorn");

ret = -EFAULT;

}

else{

led_setdata(0x00);

led_setdata((int )buffer[0]);

}

return ret;

}

static struct file_operations dev_fops ={

.owner  = THIS_MODULE,

.read = led_read,

.write = led_write,

};

static struct miscdevice misc ={

.minor = MISC_DYNAMIC_MINOR,

.name = DEVICE_NAME,

.fops = &dev_fops,

};

static int __init dev_init(void)

{

int ret;

led_pin_setup();

ret  = misc_register(&misc);

printk(DEVICE_NAME"initialize minor =%dn",misc.minor);

return ret;

}

static void __exit dev_exit(void)

{

led_pin_release();

misc_deregister(&misc);

}

module_init(dev_init);

module_exit(dev_exit);

MODULE_LICENSE("GPL");

MODULE_AUTHOR("GOAT.ZHOU");

以上的是led的驅(qū)動文件，以write 向led里寫數(shù)據(jù)，read讀取led的狀態(tài)。

以下的是測試程序 led_app.c

#include

#include

#include

#include

#include

#include

#include

char binstr_to_int(char *binstr)

{

    char ret = 0, i = 0;

    char bnum[5];

    memset(bnum, '0', 4);

    int len = strlen(binstr);

    if (len > 4) 

        strcpy(bnum, binstr+len-4); 

    else 

        strcpy(bnum+4-len, binstr);

    for (i=0; i<4; i++) {

        ret <<= 1;

        ret += (bnum[i]=='0'? 1: 0);

    }

    return ret;

}

int main(int argc, char *argv[])

{

int fd;

unsigned char buff[1];

fd = open("/dev/led1",O_RDWR);

if(fd == -1){

printf("open dev error");

_exit(EXIT_FAILURE);

}

buff[0] = binstr_to_int(argv[1]);

write(fd,buff,sizeof(buff));

memset(buff,0,sizeof(buff));

printf("%dn", read(fd,buff,sizeof(buff)));

printf("%d",(int)buff[0]);

close(fd);

return 0;

}