230726作业

myled.c

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


char kbuf[128] = {0};
gpio_t *vir_md;
gpio_t *vir_led1;
gpio_t *vir_led2;
gpio_t *vir_led3;
struct cdev *cdev;
unsigned int *vir_rcc;
struct class *cls;
struct device *dev;
unsigned int major = 500;
unsigned int minor = 0;
dev_t devno;
int mycdev_open(struct inode *inode, struct file *file)
{
    int a = inode->i_rdev;//获取当前设备号
    file->private_data = (void *)MINOR(a);//将次设备号保存到当前文件的file结构中
    printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);
    return 0;
}
long mycdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
    unsigned int a = (unsigned int)file->private_data;
    switch (cmd)
    {
    case LED_ON:
        switch (a)
        {
        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 (a)
        {
        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;
    }
    return 0;
}
int mycdev_close(struct inode *inode, struct file *file)
{
     printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    return 0;
}
//定义一个操作方法结构体变量并且初始化
struct file_operations fops={
    .open=mycdev_open,
    .release=mycdev_close,
    .unlocked_ioctl = mycdev_ioctl,
};
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;
    //申请对象空间 cdev_alloc
    cdev = cdev_alloc();
    if(cdev ==  NULL){
        printk("申请独享空间失败\n");
        ret = -EFAULT;
        goto OUT1;
    }
   //初始化对象 cdev_init
   cdev_init(cdev,&fops);
   //申请设备号
   if(major == 0){
    //动态申请
    ret = alloc_chrdev_region(&devno, minor, 3, "mydev");
    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,"mydev");
        if(ret){
            printk("静态指定设备号失败\n");
            goto OUT2;
        }
   }
   printk("设备号申请成功\n");
   //注册驱动
    ret = cdev_add(cdev,MKDEV(major,minor),3);
    if(ret){
        printk("注册驱动对象失败\n");
        goto OUT3;
    }
    printk("注册驱动对象成功\n");
    //向上提交目录
    cls = class_create(THIS_MODULE,"mycdev");
    if(IS_ERR(cls)){
        printk("向上提交目录失败\n");
        ret = -PTR_ERR(cls);
        goto OUT4;
    }
    printk("向上提交目录成功\n");
    //向上提交设备节点
    int i;
    for(i=0;i<3;i++){
        dev = device_create(cls,NULL,MKDEV(major,minor),NULL, "myled%d",i);
        if(IS_ERR(dev)){
            printk("向上提交设备节点失败\n");
            ret = -PTR_ERR(dev);
            goto OUT5;
        }
    }
     printk("向上提交设备节点成功\n");
    all_led_init();
OUT5:
    for(--i;i>=0;i--){
        device_destroy(cls,MKDEV(major,i));
    }
    class_destroy(cls);
OUT4:
    cdev_del(cdev);
OUT3:
    unregister_chrdev_region(MKDEV(major,minor),3);
OUT2:
    kfree(cdev);
OUT1:
    return -ret;
}
static void __exit mycdev_exit(void)
{
    int i;
    for(i=0;i<3;i++){
        device_destroy(cls,MKDEV(major,i));
    }
    class_destroy(cls);
    cdev_del(cdev);
    unregister_chrdev_region(MKDEV(major,minor),3);
    kfree(cdev);
}
module_init(mycdev_init);
module_exit(mycdev_exit);
MODULE_LICENSE("GPL");

头文件
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_LED1_ADDR 0X50006000
#define PHY_LED2_ADDR    0X50007000
#define PHY_LED3_ADDR 0X50006000
#define PHY_RCC_ADDR    0X50000A28
//开关灯 ioctl三参设置
#define LED_ON _IOW('l',1,int)
#define LED_OFF _IOW('l',0,int)
#endif 

操作文件
test.c

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

int main(int argc, char const *argv[])
{
    int a,b;
    while(1)
    {
        int fd;
        //从终端读取
        printf("1(led灯1) 2(led灯2) 3(led灯3)\n");
        printf("请输入>");
        scanf("%d",&a);
        switch (b)
        {
        case 1:
        fd=open("/dev/mymd0",O_RDWR);
        break;
        case 2:
        fd=open("/dev/mymd1",O_RDWR);
        break;
        case 3:
        fd=open("/dev/mymd2",O_RDWR);
        break;
        }
        if(fd<0)
        {
            printf("打开设备文件失败\n");
            exit(-1);
        }
        //从终端读取
        printf("0(关灯) 1(开灯)\n");
        printf("请输入>");
        scanf("%d",&b);
        switch (b)
        {
        case 0:
            ioctl(fd,LED_OFF);
            break;
        case 1:
            ioctl(fd,LED_ON);
            break;
        }
        close(fd);
    }

    
    

    return 0;
}