Linux驱动【day2】

mychrdev.c:

c 复制代码

#include <linux/init.h>
#include <linux/module.h>
#include <linux/fs.h>
#include<linux/uaccess.h>
#include<linux/io.h>
#include"head.h"
unsigned int major; // 保存主设备号
char kbuf[128]={0};
unsigned int *vir_moder;
unsigned int *vir_odr;
unsigned int *vir_rcc;

unsigned int *vir_moder2;
unsigned int *vir_odr2;
unsigned int *vir_rcc2;

// 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;
    ret=copy_to_user(ubuf,kbuf,size);
    if(ret)
    {
        printk("copy_to_user err\n");
        return -EIO;
    }
    
    return 0;
}
ssize_t mycdev_write(struct file *file, const char *ubuf, size_t size, loff_t *lof)
{
    
    int ret;
    //从用户拷贝
    ret=copy_from_user(kbuf,ubuf,size);
    if(ret)
    {
        printk("copy_from_user err\n");
        return -EIO;
    }
    if(kbuf[0]=='1')//PE10开灯
    {
        //开灯逻辑
        (*vir_odr) |= (0X1<<10);
    }
    else if(kbuf[0]=='0')
    {
        //关灯逻辑
        (*vir_odr) &= (~(0X1<<10));
    }

    if(kbuf[1]=='1')//PF10开灯
    {
        //开灯逻辑
        (*vir_odr2) |= (0X1<<10);
    }
    else if(kbuf[0]=='0')
    {
        //关灯逻辑
        (*vir_odr2) &= (~(0X1<<10));
    }

    if(kbuf[2]=='1')//PE8开灯
    {
        //开灯逻辑
        (*vir_odr) |= (0X1<<8);
    }
    else if(kbuf[0]=='0')
    {
        //关灯逻辑
        (*vir_odr) &= (~(0X1<<8));
    }

    return 0;
}
int mycdev_close(struct inode *inode, struct file *file)
{
    printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    return 0;
}
// 定义一个操作方法结构体对象并且初始化
struct file_operations fops = {
    .open=mycdev_open,
    .read=mycdev_read,
    .write=mycdev_write,
    .release=mycdev_close,
};
static int __init mycdev_init(void)
{
    // 字符设备驱动的注册
    major = register_chrdev(0, "mychrdev", &fops);
    if (major < 0)
    {
        printk("字符设备驱动注册失败\n");
        return major;
    }
    printk("字符设备驱动注册成功major=%d\n",major);
    //进行GPIE相关寄存器的内存映射
    vir_odr=ioremap(LED1_ODR,4);
    if(vir_odr==NULL)
    {
        printk("物理内存映射失败%d\n",__LINE__);
        return -EFAULT;
    }
    vir_rcc=ioremap(LED1_RCC,4);
    if(vir_rcc==NULL)
    {
        printk("物理内存映射失败%d\n",__LINE__);
        return -EFAULT;
    }
    vir_moder=ioremap(LED1_MODER,4);
    if(vir_moder==NULL)
    {
        printk("物理内存映射失败%d\n",__LINE__);
        return -EFAULT;
    }
    printk("寄存器内存映射成功\n");

    //进行GPIOF相关寄存器的内存映射
    vir_odr2=ioremap(LED2_ODR,4);
    if(vir_odr2==NULL)
    {
        printk("物理内存映射失败%d\n",__LINE__);
        return -EFAULT;
    }
    vir_rcc2=ioremap(LED2_RCC,4);
    if(vir_rcc2==NULL)
    {
        printk("物理内存映射失败%d\n",__LINE__);
        return -EFAULT;
    }
    vir_moder2=ioremap(LED2_MODER,4);
    if(vir_moder2==NULL)
    {
        printk("物理内存映射失败%d\n",__LINE__);
        return -EFAULT;
    }
    printk("寄存器内存映射成功\n");

    //PE10硬件寄存器的初始化
    //RCC使能
    (*vir_rcc) |= (0X1<<4);
    //设置PE10为输出
    (*vir_moder) &= (~(0X3<<20));
    (*vir_moder) |= (0X1<<20);
    //默认关灯
    (*vir_odr) &= (~(0X1<<10));

    //PF10硬件寄存器的初始化
    //RCC使能
    (*vir_rcc2) |= (0X1<<5);
    //设置PF10为输出
    (*vir_moder2) &= (~(0X3<<20));
    (*vir_moder2) |= (0X1<<20);
    //默认关灯
    (*vir_odr2) &= (~(0X1<<10));

    //PE8硬件寄存器的初始化
    //设置PE10为输出
    (*vir_moder) &= (~(0X3<<16));
    (*vir_moder) |= (0X1<<16);
    //默认关灯
    (*vir_odr) &= (~(0X1<<8));
    
    return 0;
}
static void __exit mycdev_exit(void)
{
    //取消物理内存映射
    iounmap(vir_moder);
    iounmap(vir_odr);
    iounmap(vir_rcc);

    //取消物理内存映射
    iounmap(vir_moder2);
    iounmap(vir_odr2);
    iounmap(vir_rcc2);

    // 字符设备驱动注销
    unregister_chrdev(major, "mychrdev");
}
module_init(mycdev_init);
module_exit(mycdev_exit);
MODULE_LICENSE("GPL");

test.c:

c 复制代码

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.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("设备文件打开失败\n");
        exit(-1);
    }
    while (1)
    {
        printf("输入指令控制开/关灯(LED1|LED2|LED3)==>0(OFF)/1(ON)>");
        fgets(buf, sizeof(buf), stdin); // 在终端输入数据传递到buf
        buf[strlen(buf) - 1] = '\0';    // 替换末尾的'\n'
        write(fd, buf, sizeof(buf));
    }
    close(fd);
 
    return 0;
}

head.h:

c 复制代码

#ifndef __HEAD_H__
#define __HEAD_H__

//PE10
#define LED1_RCC 0X50000A28
#define LED1_MODER 0X50006000
#define LED1_ODR  0X50006014

//PF10
#define LED2_RCC 0X50000A28
#define LED2_MODER 0X50007000
#define LED2_ODR 0X50007014

#endif

实验结果：