【day4】驱动

1.通过字符设备驱动分步注册方式编写LED灯的驱动，应用程序使用ioctl函数编写硬件控制逻辑
驱动：

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

int major;
char kbuf[128] = {0};
gpio_t *vir_led1;
gpio_t *vir_led2;
gpio_t *vir_led3;
unsigned int *vir_rcc;
struct class *cls;
struct device *dev;
//定义一个自旋锁
spinlock_t lock;
int mycdev_open(struct inode *inode, struct file *file)
{
   
    printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);
    int a=inode->i_rdev;
    file->private_data=(void *)MINOR(a);
    return 0;
}
long mycdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
    unsigned int a= (unsigned int)file->private_data;
    int which;
    int ret=copy_from_user(&which,(void *)arg,4);
    //上锁
    spin_lock(&lock);
    switch (cmd)
    {
    case LED_ON:
        switch (which)
        {
        case 1:                           // LED1
            vir_led1->ODR |= (0x1 << 10); // LED1开灯
            break;
        case 2:                           // LED2
            vir_led2->ODR |= (0x1 << 10); // LED2开灯
            break;
        case 3:                          // LED3
            vir_led3->ODR |= (0x1 << 8); // LED3开灯
            break;
        }

        break;
    case LED_OFF:
        switch (which)
        {
        case 1:
            vir_led1->ODR &= (~(0X1 << 10));
            break;
        case 2:
            vir_led2->ODR &= (~(0X1 << 10));
            break;
        case 3:
            vir_led3->ODR &= (~(0X1 << 8));
            break;
        }

        break;
    }
    //解锁
      spin_unlock(&lock);
    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,
    .unlocked_ioctl = mycdev_ioctl,
    .release = mycdev_close,
};

int all_led_init(void)
{
    // 寄存器地址的映射
    vir_led1 = ioremap(PHY_LED1_ADDR, sizeof(gpio_t));
    if (vir_led1 == NULL)
    {
        printk("ioremap filed：%d\n", __LINE__);
        return -ENOMEM;
    }
    vir_led2 = ioremap(PHY_LED2_ADDR, sizeof(gpio_t));
    if (vir_led2 == NULL)
    {
        printk("ioremap filed：%d\n", __LINE__);
        return -ENOMEM;
    }
    vir_led3 = vir_led1;
    vir_rcc = ioremap(PHY_RCC_ADDR, 4);
    if (vir_rcc == NULL)
    {
        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 int __init mycdev_init(void)
{
    int i;
    //初始化自旋锁
    spin_lock_init(&lock);  
    // 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);
    // 向上提交目录
    cls = class_create(THIS_MODULE, "myled");
    if (IS_ERR(cls))
    {
        printk("向上提交目录失败\n");
        return -PTR_ERR(cls);
    }
    printk("向上提交目录信息成功\n");
    // 向上提交设备节点信息
    for (i = 0; i < 3; i++)
    {
        dev = device_create(cls, NULL, MKDEV(major, i), NULL, "myled%d", i);
        if (IS_ERR(dev))
        {
            printk("向上提交设备节点信息失败\n");
            return -PTR_ERR(dev);
        }
    }
    printk("向上提交设备节点成功\n");
    // 寄存器映射以及初始化
    all_led_init();

    return 0;
}
static void __exit mycdev_exit(void)
{
    // 取消地址映射
    iounmap(vir_led1);
    iounmap(vir_led2);
    iounmap(vir_rcc);
    // 销毁节点信息
    int i;
    for (i = 0; i < 3; i++)
    {
        device_destroy(cls, MKDEV(major, i));
    }
    // 销毁目录信息
    class_destroy(cls);
    // 注销字符设备驱动
    unregister_chrdev(major, "mychrdev");
}
module_init(mycdev_init);
module_exit(mycdev_exit);
MODULE_LICENSE("GPL");

应用程序：

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

int main(int argc, char const *argv[])
{
    int a,b;
    char buf[128]={0};
    int fd=open("/dev/myled0",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("请输入指令\n");
        printf("0(关灯) 1(开灯)\n");
        printf("请输入>");
        scanf("%d",&a);
        printf("请输入要控制的灯 1(LED1) 2(LED2) 3(LED3)>");
        scanf("%d",&b);
        switch(a)
        {
            case 1:
                ioctl(fd,LED_ON,&b);//开灯
                break;
            case 0:
                ioctl(fd,LED_OFF,&b);
                break;
        }
        
    }

    
    close(fd);

    return 0;
}

头文件：

#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_LED1_ADDR 0X50006000
#define PHY_LED2_ADDR    0X50007000
#define PHY_LED3_ADDR 0X50006000
#define PHY_RCC_ADDR    0X50000A28
//功能码
  #define LED_ON _IOW('l',1,int)
  #define LED_OFF _IOW('l',0,int)
#endif