驱动开发day2:实现三盏灯的控制

head.h

#ifndef __HEAD_H__
#define __HEAD_H__

typedef struct{
    unsigned int MODER;
    unsigned int OTYPER;
    unsigned int OSPEEDR;
    unsigned int PUPDR;
    unsigned int IDR;
    unsigned int ODR;
}gpio_t;

#define PHY_GPIOE 0X50006000
#define PHY_GPIOF 0X50007000
#define PHY_RCC   0X50000A28

#endif

demo.c

#include 
#include 
#include
#include
#include"head.h"

int major;
char kbuf[128]={0};     //存放传入内核的数据
gpio_t *vir_led1;
gpio_t *vir_led2;
gpio_t *vir_led3;
unsigned int *vir_rcc;

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;

    //向用户空间读取拷贝
    if(size > sizeof(kbuf))     //内核最大输入限制
        size = sizeof(kbuf);
    ret = copy_to_user(ubuf, kbuf, size);
    if (ret)    //拷贝失败
    {
        printk("copy_to_user filed\n");
        return ret;
    }
    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;

    //从用户空间读取数据
    if(size > sizeof(kbuf))     //内核最大输入限制
        size = sizeof(kbuf);
    ret = copy_from_user(kbuf, ubuf, size);
    if (ret)    //拷贝失败
    {
        printk("copy_to_user filed\n");
        return ret;
    }

    switch(kbuf[0])
    {
        case '1':   //LED1
            if (kbuf[1]  ==  '0')    //关灯
                vir_led1->ODR &= (~(1<<10));
            else    //开灯
                vir_led1->ODR |= 1<<10;
            break;

        case '2':   //LED2
            if (kbuf[1]  ==  '0')   //关灯
                vir_led2->ODR &= (~(1<<10));
            else//开灯
                vir_led2->ODR |= 1<<10;
            break;

        case '3':   //LED3
            if (kbuf[1] == '0')   //关灯
                vir_led3->ODR &= (~(1<<8));
            else    //开灯
                vir_led3->ODR |= 1<<8;
            break;
    }

    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赋值
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);


    //寄存器地址的映射
    vir_led1 = ioremap(PHY_GPIOE, sizeof(gpio_t));
    if (NULL == vir_led1)
    {
        printk("ioremap filed：%d\n", __LINE__);
        return -ENOMEM;
    }

    vir_led2 = ioremap(PHY_GPIOF, sizeof(gpio_t));
    if (NULL == vir_led2)
    {
        printk("ioremap filed：%d\n", __LINE__);
        return -ENOMEM;
    }

    vir_led3 = ioremap(PHY_GPIOE, sizeof(gpio_t));
    if (NULL == vir_led1)
    {
        printk("ioremap filed：%d\n", __LINE__);
        return -ENOMEM;
    }

    vir_rcc = ioremap(PHY_RCC, 4);
    if (NULL == vir_rcc)
    {
        printk("ioremap filed：%d\n", __LINE__);
        return -ENOMEM;
    }

    printk("物理地址映射成功\n");


    //寄存器的初始化
    //rcc
    (*vir_rcc) |= (3<<4);

    //led1
    vir_led1->MODER &= (~(3<<20));
    vir_led1->MODER |= (1<<20);
    vir_led1->ODR &= (~(1<<10));

    //led2
    vir_led2->MODER &= (~(3<<20));
    vir_led2->MODER |= (1<<20);
    vir_led2->ODR &= (~(1<<10));

    //led3
    vir_led3->MODER &= (~(3<<16));
    vir_led1->MODER |= (1<<16);
    vir_led1->ODR &= (~(1<<8));

    printk("寄存器初始化成功\n");


    return 0;
} 

static void __exit mycdev_exit(void)
{
    //取消地址映射
    iounmap(vir_led1);
    iounmap(vir_led2);
    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");

text.c

#include 
#include 
#include 
#include 
#include 
#include 
#include 

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)
    {
        //从终端读取
        printf("请输入两个字符\n");
        printf("第一个字符:1(LED1) 2(LED2) 3(LED3)\n");
        printf("第二个字符:0(关灯) 1(开灯)\n");
        printf("请输入>>>");
        
        fgets(buf,sizeof(buf), stdin);
        buf[strlen(buf)-1] = '\0';

        //向设备文件中写
        write(fd, buf, sizeof(buf));
    }

    close(fd);

    return 0;
}