驱动点灯

#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;
char kbuf[128] = {};
// 定义三个指针指向映射后的虚拟内存
unsigned int *vir_moder_led1;
unsigned int *vir_odr_led1;
unsigned int *vir_rcc;
 
unsigned int *vir_moder_led2;
unsigned int *vir_odr_led2;
 
unsigned int *vir_moder_led3;
unsigned int *vir_odr_led3;
// 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;
    // 将数据拷贝到用户空间
    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;
    // 将用户空间的数据拷贝到内核空间
    ret = copy_from_user(kbuf, ubuf, size);
    if (ret)
    {
        printk("copy_from_user filed\n");
        return -EIO;
    }
    if(kbuf[0] == '0')
    {
        //关灯逻辑
        (*vir_odr_led1) &= (~(0x1 << 10));
        (*vir_odr_led2) &= (~(0x1 << 10));
        (*vir_odr_led3) &= (~(0x1 << 8));
    }
    else if(kbuf[0] == '1')
    {
        //开灯逻辑
        (*vir_odr_led1) |= (0x1 << 10);
        (*vir_odr_led2) |= (0x1 << 10);
        (*vir_odr_led3) |= (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 mycdev_init(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
    vir_moder_led1 = ioremap(PHY_LED1_MODER, 4);
    if (vir_moder_led1 == NULL)
    {
        printk("物理内存地址映射失败%d\n", __LINE__);
        return -EFAULT;
    }
    vir_odr_led1 = ioremap(PHY_LED1_ODR, 4);
    if (vir_odr_led1 == NULL)
    {
        printk("物理内存地址映射失败%d\n", __LINE__);
        return -EFAULT;
    }
 
    vir_moder_led2 = ioremap(PHY_LED2_MODER, 4);
    if (vir_moder_led2 == NULL)
    {
        printk("物理内存地址映射失败%d\n", __LINE__);
        return -EFAULT;
    }
    vir_odr_led2 = ioremap(PHY_LED2_ODR, 4);
    if (vir_odr_led2 == NULL)
    {
        printk("物理内存地址映射失败%d\n", __LINE__);
        return -EFAULT;
    }
 
    vir_moder_led3 = ioremap(PHY_LED3_MODER, 4);
    if (vir_moder_led3 == NULL)
    {
        printk("物理内存地址映射失败%d\n", __LINE__);
        return -EFAULT;
    }
    vir_odr_led3 = ioremap(PHY_LED3_ODR, 4);
    if (vir_odr_led3 == 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("寄存器内存映射成功\n");
 
    // LED1寄存器初始化
    (*vir_rcc) |= (0x1 << 4); // GPIOE控制器时钟使能
    (*vir_moder_led1) &= (~(0x3 << 20));
    (*vir_moder_led1) |= (0x1 << 20);
    (*vir_odr_led1) &= (~(0x1 << 10)); // 默认关灯
 
    // LED2寄存器初始化
    (*vir_rcc) |= (0x1 << 5); //GPIOF控制器时钟使能
    (*vir_moder_led2) &= (~(0x3 << 20));
    (*vir_moder_led2) |= (0x1 << 20);
    (*vir_odr_led2) &= (~(0x1 << 10)); // 默认关灯
 
    // LED3寄存器初始化
    (*vir_moder_led3) &= (~(0x3 << 16));
    (*vir_moder_led3) |= (0x1 << 16);
    (*vir_odr_led3) &= (~(0x1 << 8)); // 默认关灯
 
    return 0;
}
 
static void __exit mycdev_exit(void)
{
    // 取消内存映射
    iounmap(vir_moder_led1);
    iounmap(vir_odr_led1);
 
    iounmap(vir_moder_led2);
    iounmap(vir_odr_led2);
 
    iounmap(vir_moder_led3);
    iounmap(vir_odr_led3);
    iounmap(vir_rcc);
    // 注销字符设备驱动
    unregister_chrdev(major, "mychrdev");
}
 
module_init(mycdev_init);
module_exit(mycdev_exit);
MODULE_LICENSE("GPL");

#ifndef __HEAD_H__
#define __HEAD_H__
 
#define PHY_LED1_MODER 0x50006000
#define PHY_LED1_ODR   0x50006014
#define PHY_RCC        0x50000A28
 
#define PHY_LED2_MODER 0x50007000
#define PHY_LED2_ODR   0x50007014
 
#define PHY_LED3_MODER 0x50006000
#define PHY_LED3_ODR   0x50006014
 
#endif

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
 
int main()
{
    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("请输入进行的操作:0(关灯),1(开灯)>>");
 
        fgets(buf, sizeof(buf), stdin); // 在终端读一个字符串
        buf[strlen(buf) - 1] = '\0';
 
        write(fd, buf, sizeof(buf)); // 将数据传递给内核
    }
    close(fd);
    return 0;
}