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Linux驱动【day2】

news 2025/7/10 1:13:45

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"
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:

#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bufbuf[strlen(buf) - 1] = '\0';    // 替换末尾的'\n'write(fd, buf, sizeof(buf));}close(fd);return 0;
}

head.h:

#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