驱动day4 - 技术栈

头文件：

复制代码

#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

// 构建开灯关灯的功能码
#define LED_ON _IOW('l', 1,int)
#define LED_OFF _IOW('l', 0,int)
#endif

运行代码：

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#include<stdlib.h>
#include<stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include<unistd.h>
#include<string.h>
#include "head.h"

int main(int argc, char const *argv[])
{
    char buf[128]={0};
    int a,b,fd;
    if(fd<0)
    {
        printf("打开设备文件失败\n");
        exit(-1);
    }

    while(1)
    {
        fd=-1;
        //从终端读取
        printf("请输入要实现的功能 ");
        printf("0(关灯) 1(开灯)\n");
        printf("请输入>");
        scanf("%d",&a);
        printf("请选择要控制的灯：1（LED1）2(LED2) 3(LED3)\n");
        printf("请输入>");
        scanf("%d",&b);
        switch(b)
        {
            case 1:
                fd=open("/dev/burger0",O_RDWR);
                if(a == 0)
                {   
                   ioctl(fd,LED_ON,&b);
                    break;
                }
                else
                {
                    ioctl(fd,LED_OFF,&b);
                    break;
                }
            case 2:
                fd=open("/dev/burger1",O_RDWR);
                if(a == 0)
                {   
                   ioctl(fd,LED_ON,&b);
                    break;
                }
                else
                {
                    ioctl(fd,LED_OFF,&b);
                    break;
                }
            case 3:
                fd=open("/dev/burger2",O_RDWR);
                if(a == 0)
                {   
                   ioctl(fd,LED_ON,&b);
                    break;
                }
                else
                {
                    ioctl(fd,LED_OFF,&b);
                    break;
                }
        }
        close(fd);
    }
    close(fd);
    return 0;
}

驱动代码：

复制代码

#include <linux/init.h>
#include <linux/module.h>
#include<linux/fs.h>
#include<linux/io.h>
#include <linux/uaccess.h>
#include <linux/device.h>
#include <linux/cdev.h>
#include <linux/slab.h>
#include"head.h"

char kbuf[128]={0};
gpio_t *vir_led1;
gpio_t *vir_led2;
gpio_t *vir_led3;
unsigned int *vir_rcc;
unsigned int major=0;
unsigned int minor=0;
struct cdev *mychdev;
struct class *cls;
struct device *dev;
dev_t devno;
int mycdev_open(struct inode *inode, struct file *file)
{
    int min=MINOR(inode->i_rdev);//获取打开的的文件的次设备号
    file->private_data= (void *)min;
    printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);
    return 0;
}
long mycdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
    int min=(int)file->private_data;//获取到文件的次设备号
    switch(min)
    {
        case 0: //控制LED1
            switch(cmd)
            {
                case LED_ON:  //开灯
                    vir_led1->ODR |= 1<<10;
                    break;
                case LED_OFF: //关灯
                    vir_led1->ODR &= (~(1<<10));
                    break;
            }
            break;
        case 1:  //控制LED2
            switch(cmd)
            {
                case LED_ON:  //开灯
                    vir_led2->ODR |= 1<<10;
                    break;
                case LED_OFF: //关灯
                    vir_led2->ODR &= (~(1<<10));
                    break;
            }
            break;
        case 2:  //控制LED3
            switch(cmd)
            {
                case LED_ON:  //开灯
                    vir_led3->ODR |= 1<<8;
                    break;
                case LED_OFF: //关灯
                    vir_led3->ODR &= (~(1<<8));
                    break;
            }
            break;
    }
     printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);
    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 ret;
    //1.申请一个对象空间cdev_alloc
    mychdev=cdev_alloc();
    if(mychdev == NULL)
    {
        printk("申请字符设备驱动对象失败\n");
        ret = -EFAULT;
        goto out1;
    }
    printk("申请字符设备驱动对象成功\n");
    //2.初始化对象cdev_init
    cdev_init(mychdev,&fops);
    //3.申请设备号  register_chrdev_region()/alloc_chrdev_region()
    if(major == 0)
    {
        ret = alloc_chrdev_region(&devno,minor,3,"burger");
        if(ret)
        {
            printk("动态申请设备号失败\n");
            goto out2;
        }
        major=MAJOR(devno);
        minor=MINOR(devno);
    }
    else
    {
        ret = register_chrdev_region(MKDEV(major,minor),3,"burger");
        if(ret)
        {
            printk("静态申请设备号失败\n");
            goto out2;
        }
    }
    printk("申请设备号成功\n");
    //4.注册驱动对象  cdev_add
    ret = cdev_add(mychdev,MKDEV(major,minor),3);
    if(ret)
    {
        printk("注册字符设备驱动对象失败\n");
        goto out3;
    }
    printk("注册字符设备驱动对象成功\n");
    //5.向上提交目录  class_create
    cls=class_create(THIS_MODULE,"burger");
    if(IS_ERR(cls))
    {
        printk("向上提交目录失败\n");
        goto out4;
    }
    printk("向上提交目录成功\n");
    //6.向上提交设备节点信息  device_create
    int i;  //向上提交三次设备节点信息
    for(i=0;i<3;i++)
    {
        dev=device_create(cls,NULL,MKDEV(major,i),NULL,"burger%d",i);
        if(IS_ERR(dev))
        {
            printk("向上提交节点失败\n");
            goto out5;
        }
    }
     printk("向上提交节点成功\n");
	return 0;
out5:
    for(--i;i>=0;i--)
    {
        device_destroy(cls,MKDEV(major,i));
    }
    class_destroy(cls);
out4:
    cdev_del(mychdev);
out3:
    unregister_chrdev_region(MKDEV(major,minor),3);
out2:
    kfree(mychdev);
out1:
    return ret;
}
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
    int i;
    for(i=0;i<3;i++)
    {
        device_destroy(cls,MKDEV(major,i));
    }
    class_destroy(cls);
    cdev_del(mychdev);
    unregister_chrdev_region(MKDEV(major,minor),3);
    kfree(mychdev);


}
module_init(mycdev_init);
module_exit(mycdev_exit);
MODULE_LICENSE("GPL");