头文件
cs
#ifndef __HEAD_H__
#define __HEAD_H__
//LED1和LED3的硬件地址
#define PHY_LED1_MODER 0x50006000
#define PHY_LED1_ODR 0x50006014
#define PHY_LED1_RCC 0x50000A28
//LED2的硬件地址
#define PHY_LED2_MODER 0x50007000
#define PHY_LED2_ODR 0x50007014
#define PHY_LED2_RCC 0x50000A28
#endif驱动代码
cs
#include <linux/init.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include <linux/device.h>
#include "head.h"
int major;
char kbuf[128]={0};
//定义指针接收映射成功的虚拟内存首地址
unsigned int *vir_moder1;
unsigned int *vir_odr1;
unsigned int *vir_rcc1;
unsigned int *vir_moder2;
unsigned int *vir_odr2;
unsigned int *vir_rcc2;
//定义一个指针用来接收创建类
struct class *cls;
//定义一个指针用来接收接收创建设备信息
struct device *dev;
// 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 filad\n");
return ret;
}
return 0;
}
ssize_t mycdev_write(struct file *file, const char *ubuf, size_t size, loff_t *lof)
{
int ret;
ret=copy_from_user(kbuf,ubuf,size);
if(ret)
{
printk("copy_from_user filed\n");
return ret;
}
if(kbuf[0]=='1' && kbuf[1] == '1')//LED1开灯
{
//开灯逻辑
(*vir_odr1) |= (0X1<<10);
}
else if(kbuf[0]=='1' && kbuf[1] == '0')//LED1关灯
{
//关灯逻辑
(*vir_odr1) &= (~(0X1<<10));
}
else if(kbuf[0]=='2' && kbuf[1] == '1')//LED2开灯
{
//开灯逻辑
(*vir_odr2) |= (0X1<<10);
}
else if(kbuf[0]=='2' && kbuf[1] == '0')//LED1关灯
{
//关灯逻辑
(*vir_odr2) &= (~(0X1<<10));
}
else if(kbuf[0]=='3' && kbuf[1] == '1')//LED#开灯
{
//开灯逻辑
(*vir_odr1) |= (0X1<<8);
}
else if(kbuf[0]=='3' && kbuf[1] == '0')//LED3关灯
{
//关灯逻辑
(*vir_odr1) &= (~(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遍历并且初始化
struct file_operations fops = {
.open=mycdev_open,
.read=mycdev_read,
.write=mycdev_write,
.release=mycdev_close,
};
static int __init mycdev_init(void)
{
int i;
// 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("字符设备驱动注册成功major=%d\n",major);
//向上提交目录信息
cls = class_create(THIS_MODULE,"mycdev");
if(IS_ERR(cls))
{
printk("向上提交目录信息失败\n");
return -PTR_ERR(cls);
}
printk("向上提交目录信息成功\n");
//向上提交设备信息
for(i=0;i<3;i++)
{
dev=device_create(cls,NULL,MKDEV(major,i),NULL,"mycdev%d",i);
if(IS_ERR(cls))
{
printk("向上提交设备信息信息失败\n");
return -PTR_ERR(cls);
}
}
printk("向上提交设备信息成功\n");
//完成硬件寄存器物理内存的映射
vir_moder1=ioremap(PHY_LED1_MODER,4);
if(vir_moder1==NULL)
{
printk("LED1物理内存映射失败%d\n",__LINE__);
return -EFAULT;
}
vir_odr1=ioremap(PHY_LED1_ODR,4);
if(vir_odr1==NULL)
{
printk("LED1物理内存映射失败%d\n",__LINE__);
return -EFAULT;
}
vir_rcc1=ioremap(PHY_LED1_RCC,4);
if(vir_rcc1==NULL)
{
printk("LED1物理内存映射失败%d\n",__LINE__);
return -EFAULT;
}
printk("LED1物理内存映射成功\n");
//LED2物理内存映射
vir_moder2=ioremap(PHY_LED2_MODER,4);
if(vir_moder2==NULL)
{
printk("LED2物理内存映射失败%d\n",__LINE__);
return -EFAULT;
}
vir_odr2=ioremap(PHY_LED2_ODR,4);
if(vir_odr2==NULL)
{
printk("LED2物理内存映射失败%d\n",__LINE__);
return -EFAULT;
}
vir_rcc2=ioremap(PHY_LED2_RCC,4);
if(vir_rcc2==NULL)
{
printk("LED2物理内存映射失败%d\n",__LINE__);
return -EFAULT;
}
printk("LED2物理内存映射成功\n");
//LED3物理内存映射
vir_moder1=ioremap(PHY_LED1_MODER,4);
if(vir_moder1==NULL)
{
printk("LED3物理内存映射失败%d\n",__LINE__);
return -EFAULT;
}
vir_odr1=ioremap(PHY_LED1_ODR,4);
if(vir_odr1==NULL)
{
printk("LED3物理内存映射失败%d\n",__LINE__);
return -EFAULT;
}
vir_rcc1=ioremap(PHY_LED1_RCC,4);
if(vir_rcc1==NULL)
{
printk("LED3物理内存映射失败%d\n",__LINE__);
return -EFAULT;
}
printk("LED3物理内存映射成功\n");
//硬件寄存器的初始化
//LED1硬件初始化
(*vir_moder1) &= (~(0X3<<20));//设置为输出
(*vir_moder1) |= (0X1<<20);
//LED2硬件初始化
(*vir_moder2) &= (~(0X3<<20));//设置为输出
(*vir_moder2) |= (0X1<<20);
//LED3硬件初始化
(*vir_moder1) &= (~(0X3<<16));//设置为输出
(*vir_moder1) |= (0X1<<16);
//rcc使能
(*vir_rcc1) |= (0X1<<4);
(*vir_rcc2) |= (0X1<<5);
//默认关灯
(*vir_odr1) &= (~(0X1<<10));
(*vir_odr2) &= (~(0X1<<10));
(*vir_odr1) &= (~(0X1<<8));
return 0;
}
static void __exit mycdev_exit(void)
{
//取消物理内存的映射
iounmap(vir_moder1);
iounmap(vir_odr1);
iounmap(vir_rcc1);
iounmap(vir_moder2);
iounmap(vir_odr2);
iounmap(vir_rcc2);
//销毁设备信息
int i;
for(i=0;i<3;i++)
{
device_destroy(cls,MKDEV(major,i));
}
//销毁目录信息
class_destroy(cls);
//字符设备驱动的注销
unregister_chrdev(major,"mychrdev");
}
module_init(mycdev_init);
module_exit(mycdev_exit);
MODULE_LICENSE("GPL");测试文件
cs
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
int main(int argc, const char *argv[])
{
char buf[128] = {};
int fd0 = open("/dev/mycdev0", O_RDWR);
int fd1 = open("/dev/mycdev1", O_RDWR);
int fd2 = open("/dev/mycdev2", O_RDWR);
if (fd0 < 0)
{
printf("打开设备文件失败\n");
exit(-1);
}
printf("成功打开设备文件\n");
while (1)
{
printf("逻辑关系：例如11表示LED1亮 10表示LED1灭...\n");
fgets(buf, sizeof(buf), stdin); // 从终端读一个字符串存放在buf
buf[strlen(buf) - 1] = '\0';
if(buf[0] == '1')
{
write(fd0, buf, sizeof(buf)); // 将从终端得到的字符串传递到驱动
}
else if(buf[0] == '2')
{
write(fd1, buf, sizeof(buf));
}
else if(buf[0] == '3')
{
write(fd2, buf, sizeof(buf));
}
}
close(fd0);
return 0;
}结果
实现效果如上