demo3.c
#include <linux/init.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/uaccess.h>
#include "head.h"
#include <linux/io.h>
unsigned int major;
char kbuf[128]={};
//定义三个指针指向映射后的虚拟内存
unsigned int *vir_moder1;
unsigned int *vir_odr1;
unsigned int *vir_moder2;
unsigned int *vir_odr2;
unsigned int *vir_moder3;
unsigned int *vir_odr3;
unsigned int *vir_rcc;
//封装操作方法
int mycdev_open(struct inode *inode,struct file *file)
{
printk("%s:%s:%d\n",FILE,func,LINE);
return 0;
}
ssize_t mycdev_read(struct file *file,char *ubuf,size_t size,loff_t *lof)
{
printk("%s:%s:%d\n",FILE,func,LINE);
int ret;
ret=copy_to_user(ubuf,kbuf,size);
if(ret)
{
printk("copy_to_user filed\n");
return -EIO;
}
return 0;
}
ssize_t mycdev_write(struct file *file,const char *ubuf,size_t size,loff_t *lof)
{
printk("%s:%s:%d\n",FILE,func,LINE);
int ret;
ret=copy_from_user(kbuf,ubuf,size);
if(ret)
{
printk("copy_from_user filed\n");
return -EIO;
}
if(kbuf[0]=='1'&&kbuf[1]=='0') //关灯
{
(*vir_odr1) &= (~(0x1 << 10));
}
else if(kbuf[0]=='1'&&kbuf[1]=='1') //开灯
{
(*vir_odr1) |= (0x1 << 10);
}
if(kbuf[0]=='2'&&kbuf[1]=='0') //关灯
{
(*vir_odr2) &= (~(0x1 << 10));
}
else if(kbuf[0]=='2'&&kbuf[1]=='1') //开灯
{
(*vir_odr2) |= (0x1 << 10);
}
if(kbuf[0]=='3'&&kbuf[1]=='0') //关灯
{
(*vir_odr3) &= (~(0x1 << 8));
}
else if(kbuf[0]=='3'&&kbuf[1]=='1') //开灯
{
(*vir_odr3) |= (0x1 << 8);
}
return 0;
}
int mycdev_close(struct inode *inode,struct file *file)
{
printk("%s:%s:%d\n",FILE,func,LINE);
return 0;
}
//定义操作方法结构体对象
struct file_operations fops={
.open=mycdev_open,
.read=mycdev_read,
.write=mycdev_write,
.release=mycdev_close,
};
static int __init s1(void)
{
//注册字符设备驱动
major = register_chrdev(0,"mychrdev",&fops);
if(major < 0)
{
printk("字符设备驱动注册失败\n");
return major;
}
printk("注册字符设备驱动成功major=%d\n",major);
//进行寄存器的地址映射，将物理地址映射为虚拟地址
vir_moder1=ioremap(PHY_LED1_MODER,4);
vir_moder2=ioremap(PHY_LED2_MODER,4);
vir_moder3=ioremap(PHY_LED3_MODER,4);
if(vir_moder1==NULL||vir_moder2==NULL||vir_moder3==NULL)
{
printk("物理内存地址映射失败%d\n",LINE);
return -EFAULT;
}
vir_odr1=ioremap(PHY_LED1_ODR,4);
vir_odr2=ioremap(PHY_LED2_ODR,4);
vir_odr3=ioremap(PHY_LED3_ODR,4);
if(vir_odr1==NULL||vir_odr2==NULL||vir_odr3==NULL)
{
printk("物理内存地址映射失败%d\n",LINE);
return -EFAULT;
}
vir_rcc=ioremap(PHY_RCC,4);
if(vir_rcc==NULL)
{
printk("物理内存地址映射失败%d\n",LINE);
return -EFAULT;
}
printk("物理内存地址映射成功\n");
(*vir_rcc) |= (0x1<<4);//GPIOE控制器时钟使能
(*vir_rcc) |= (0x1<<5);
//LED1寄存器初始化
(*vir_moder1) &= (~(0x3<<20));
(*vir_moder1) |= (0x1<<20);
(*vir_odr1) &= (~(0x1<<10));//默认关灯
//LED2寄存器初始化
(*vir_moder2) &= (~(0x3<<20));
(*vir_moder2) |= (0x1<<20);
(*vir_odr2) &= (~(0x1<<10));//默认关灯
//LED3寄存器初始化
(*vir_moder3) &= (~(0x3<<16));
(*vir_moder3) |= (0x1<<16);
(*vir_odr3) &= (~(0x1<<8));//默认关灯
return 0;
}
static void __exit s2(void)
{
//取消物理地址内存映射
iounmap(vir_rcc);
iounmap(vir_moder1);
iounmap(vir_odr1);
iounmap(vir_moder2);
iounmap(vir_odr2);
iounmap(vir_moder3);
iounmap(vir_odr3);
//注销字符设备驱动
unregister_chrdev(major,"mychrdev");
}
module_init(s1);
module_exit(s2);
MODULE_LICENSE("GPL");
head.h
#ifndef HEAD__H
#define HEAD__H
#define PHY_LED1_MODER 0x50006000
#define PHY_LED1_ODR 0x50006014
#define PHY_LED2_MODER 0x50007000
#define PHY_LED2_ODR 0x50007014
#define PHY_LED3_MODER 0x50006000
#define PHY_LED3_ODR 0x50006014
#define PHY_RCC 0x50000A28
#endif
test.c
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
#include <unistd.h>
int main(int argc,char const *argv[])
{
char buf[128]={0};
int fd=open("/dev/mychrdev",O_RDWR);
if(fd<0)
{
printf("打开设备文件失败\n");
return -1;
}
printf("打开设备文件成功\n");
while(1)
{
printf("请输入要进行的操作:0(关灯)1(开灯)");
fgets(buf,sizeof(buf),stdin);//从终端读取一个字符串
buf[strlen(buf)-1]='\0';
write(fd,buf,sizeof(buf));
memset(buf,0,sizeof(buf));
}
close(fd);
return 0;
}
