控制LED灯的亮灭

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 <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.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");
        exit(-1);
    }
    while(1)
    {
        printf("请输入控制命令--11:LED1开灯  10:LED1关灯\n21:LED2开灯  20:LED2关灯\n31:LED3开灯  30:LED3关灯>>>");
        fgets(buf,sizeof(buf),stdin);           //在终端读取
        buf[strlen(buf)-1] = '\0';
        write(fd,buf,sizeof(buf));
    }
    close(fd);
    return 0;
}

mychrdev.c

#include <linux/init.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include "head.h"
int major;      //用于保存主设备号
char kbuf[128] = {0};
unsigned int *vir_led1_moder;
unsigned int *vir_led1_odr;
unsigned int *vir_led2_moder;
unsigned int *vir_led2_odr;
unsigned int *vir_led3_moder;
unsigned int *vir_led3_odr;
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)
{
    int ret;
    if(sizeof(kbuf) < size)
        size = sizeof(kbuf);
    ret = copy_to_user(ubuf,kbuf,size);
    if(ret)
    {
        printk("copy to user filed\n");
        return -EIO;
    }
    printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    return 0;
}
ssize_t mycdev_write(struct file *file,const char *ubuf,size_t size,loff_t *lof)
{
    int ret;
    if(sizeof(kbuf) < size)
        size = sizeof(kbuf);
    ret = copy_from_user(kbuf,ubuf,size);
    if(ret)
    {
        printk("copy from user filed\n");
        return -EIO;
    }
    //LED1亮
    if(kbuf[0]=='1' && kbuf[1]=='1')
    {
        (*vir_led1_odr) |= (0x1 << 10);
    }
    //LED1灭
    else if(kbuf[0]=='1'  && kbuf[1]=='0') 
    {
        (*vir_led1_odr) &= (~(0x1 << 10));
    }
     //LED2亮
    if(kbuf[0]=='2'  && kbuf[1]=='1')
    {
        (*vir_led2_odr) |= (0x1 << 10);
    }
    //LED2灭
    else if(kbuf[0]=='2'  && kbuf[1]=='0')
    {
        (*vir_led2_odr) &= (~(0x1 << 10));
    }
     //LED3亮
    if(kbuf[0]=='3'  && kbuf[1]=='1')
    {
        (*vir_led3_odr) |= (0x1 << 8);
    }
    //LED3灭
    else if(kbuf[0]=='3'  && kbuf[1]=='0')
    {
        (*vir_led3_odr) &= (~(0x1 << 8));
    }
    printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    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变量并完成初始化
struct file_operations fops = 
{
    .open = mycdev_open,
    .read = mycdev_read,
    .write = mycdev_write,
    .release = mycdev_close,
};
static int __init mycdev_init(void)
{
    //字符设备启动注册
    major = register_chrdev(0,"mychrdev",&fops);
    if (major < 0)
    {
        printk("字符驱动设备注册失败\n");
        return major;
    }
    printk("字符驱动注册成功major = %d\n",major);
    //映射物理寄存器
    vir_led1_moder = ioremap(PHY_LED1_MODER,4);
    if(vir_led1_moder==NULL)
    {
        printk("MODER寄存器地址映射失败\n");
        return -EFAULT;
    }
    vir_led1_odr = ioremap(PHY_LED1_ODR,4);
    if(vir_led1_odr==NULL)
    {
        printk("ODR寄存器地址映射失败\n");
        return -EFAULT;
    }
    vir_led2_moder = ioremap(PHY_LED2_MODER,4);
    if(vir_led2_moder==NULL)
    {
        printk("MODER寄存器地址映射失败\n");
        return -EFAULT;
    }
    vir_led2_odr = ioremap(PHY_LED2_ODR,4);
    if(vir_led2_odr==NULL)
    {
        printk("ODR寄存器地址映射失败\n");
        return -EFAULT;
    }
    vir_led3_moder = ioremap(PHY_LED3_MODER,4);
    if(vir_led3_moder==NULL)
    {
        printk("MODER寄存器地址映射失败\n");
        return -EFAULT;
    }
    vir_led3_odr = ioremap(PHY_LED3_ODR,4);
    if(vir_led3_odr==NULL)
    {
        printk("ODR寄存器地址映射失败\n");
        return -EFAULT;
    }
    vir_rcc = ioremap(PHY_RCC,4);
    if(vir_rcc==NULL)
    {
        printk("MODER寄存器地址映射失败\n");
        return -EFAULT;
    }
    printk("寄存器地址映射成功\n");
    //寄存器初始化
    (*vir_rcc) |= (0x1 << 4);
    (*vir_rcc) |= (0x1 << 5);
    (*vir_led1_moder) &= (~(0x3 << 20));
    (*vir_led1_moder) |= (0x1 << 20);
    (*vir_led1_odr) &= (~(0x1 << 10));
    (*vir_led2_moder) &= (~(0x3 << 20));
    (*vir_led2_moder) |= (0x1 << 20);
    (*vir_led2_odr) &= (~(0x1 << 10));
    (*vir_led3_moder) &= (~(0x3 << 16));
    (*vir_led3_moder) |= (0x1 << 16);
    (*vir_led3_odr) &= (~(0x1 << 8));
    return 0;
}
static void __exit mycdev_exit(void)
{
    //取消寄存器地址映射
    iounmap(vir_led1_moder);
    iounmap(vir_led1_odr);
    iounmap(vir_led2_moder);
    iounmap(vir_led2_odr);
    iounmap(vir_led3_moder);
    iounmap(vir_led3_odr);
    iounmap(vir_rcc);
    //字符设备驱动的注销
    unregister_chrdev(major,"mychrdev");

}
module_init(mycdev_init);
module_exit(mycdev_exit);
MODULE_LICENSE("GPL");

效果展示