驱动 私有数据传参点灯

1.在串口工具进行输入：   
    echo 1 > /dev/myled0 ---->led1灯点亮
    echo 0 > /dev/myled0 ---->led1灯熄灭
    echo 1 > /dev/myled1 ---->led1灯点亮
    echo 0 > /dev/myled1 ---->led1灯熄灭
    echo 1 > /dev/myled2 ---->led1灯点亮
    echo 0 > /dev/myled2 ---->led1灯熄灭
linux@ubuntu:/sys/class/myled$ ls /dev/myled* -ll
    
crw------- 1 root root 236, 0 Nov 18 14:55 /dev/myled0 ----->控制PE10（LED1）
    crw------- 1 root root 236, 1 Nov 18 14:55 /dev/myled1----->控制PF10（LED2）
    crw------- 1 root root 236, 2 Nov 18 14:55 /dev/myled2----->控制PE8（LED3）

2.驱动：
    open:在open函数中获取到次设备号，用私有数据传参，传递给write函数
    write：在write函数，判断次设备号，就知道操作的是哪盏灯

3.要求：
    1）分部实现注册字符设备驱动
    2）自动创建设备节点
    3）通过结构体对led灯地址进行映射
    4）次设备号完成私有数据传参

#include <linux/init.h>
#include <linux/module.h>
#include<linux/fs.h>
#include<linux/uaccess.h>
#include<linux/io.h>
#include<linux/device.h>
#include <linux/ioctl.h>
#include <linux/cdev.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <uapi/linux/kdev_t.h>
#include "myled.h"
 
#define CNAME "myled"
char kbuf[128] = {0};
struct class *cls;
struct device *dev;
//虚拟地址
gpio_t *virt_gpioe;           //PE
gpio_t *virt_gpiof;             //PF
volatile unsigned int *virt_rcc;    //RCC
 
//cdev结构体指针
struct cdev *cdev;
#if 1
unsigned int major=0;   //动态申请设备号
#else
unsigned int major=500; //静态申请设备号
#endif
int minor = 0;
const int count=3;
int mycdev_open(struct inode *inode, struct file *file)
{
    
    int minor;
    minor=MINOR(inode->i_rdev);
    file->private_data=(void*)minor;
    
    printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    return 0;
}
ssize_t mycdev_read(struct file *file, char __user *ubuf, size_t size, loff_t *loff)
{
  
    printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    return size;
}
ssize_t mycdev_write (struct file *file, const char __user *ubuf, size_t size, loff_t *loff)
{
    
    int minor;
    int ret;
    minor=(int)file->private_data;
    
    switch(minor)
    {
        case 0:     //LED1---->PE10
            if(size > sizeof(kbuf))
            {
             size=sizeof(kbuf);
            }
            ret=copy_from_user(kbuf,ubuf,size);
            if(ret)
            {
                printk("传递数据失败\n");
                return -EIO;
            }
            if('0'==kbuf[0])
            {
                virt_gpioe->ODR &= (~(0x1<<10));
            }
            else
            {
                virt_gpioe->ODR |=(0x1<<10);
            }
        break;
        case 1:     //LED2---->PF10
            if(size > sizeof(kbuf))
            {
             size=sizeof(kbuf);
            }
            ret=copy_from_user(kbuf,ubuf,size);
            if(ret)
            {
                printk("传递数据失败\n");
                return -EIO;
            }
            if('0'==kbuf[0])
            {
                virt_gpiof->ODR &= (~(0x1<<10));
            }
            else
            {
                virt_gpiof->ODR |=(0x1<<10);
            }
        break;
        case 2:     //LED3---->PE8
            if(size > sizeof(kbuf))
            {
             size=sizeof(kbuf);
            }
            ret=copy_from_user(kbuf,ubuf,size);
            if(ret)
            {
                printk("传递数据失败\n");
                return -EIO;
            }
            if('0'==kbuf[0])
            {
                virt_gpioe->ODR &= (~(0x1<<8));
            }
            else
            {
                virt_gpioe->ODR |=(0x1<<8);
            }
        break;
    }
    printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
    return size;
}
long mycdev_ioctl(struct file *file,unsigned int cmd,unsigned long arg)
{
    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;
}
//操作方法结构体
const struct file_operations fops =
{
   .open = mycdev_open,
    .read = mycdev_read,
    .write = mycdev_write,
    .unlocked_ioctl = mycdev_ioctl,
    .release = mycdev_close,
};
//入口
static int __init mycdev_init(void)
{
    int i;
    int ret;
    dev_t devno;    //动态分配的设备号
    //1.分配cdev结构体
    cdev=cdev_alloc();
    if(NULL==cdev)
    {
        printk("cdev_alloc fail\n");
        goto ERR1;
        return -EIO;
    }
    //2.初始化结构体
    cdev_init(cdev,&fops);
    //3.申请设备号
    if(major>0)
    {
        //静态
        ret=register_chrdev_region(MKDEV(major,minor),count,CNAME);
        if(ret)
        {
            printk("静态申请设备号失败\n");
            ret=-ENOMEM;
            goto ERR2;
        }
    }
    else
    {
        //动态申请设备号
        ret=alloc_chrdev_region(&devno,0,count,CNAME);
        if(ret)
        {
            printk("动态申请设备失败\n");
            ret=-ENOMEM;
            goto ERR2;
        }
        major=MAJOR(devno);
        minor=MINOR(devno);
    }
 
    //4.驱动的注册
    ret=cdev_add(cdev,MKDEV(major,minor),count);
    if(ret)
    {
        printk("驱动注册失败\n");
        return -EIO;
        goto ERR3;
    }
    //5.自动创建设备节点
    cls=class_create(THIS_MODULE,CNAME);
    if(IS_ERR(cls))
    {
        printk("向上层提交目录信息失败\n");
        ret=PTR_ERR(cls);
        goto ERR4;
    }
    //提交设备结点信息
    for(i=0;i<count;i++)
    {
        dev=device_create(cls,NULL,MKDEV(major,i),NULL,"myled%d",i);
        if(IS_ERR(dev))
        {
            printk("提交设备结点信息失败\n");
            ret=PTR_ERR(dev);
            goto ERR5;
        }
    }
    //对灯地址进行映射
    virt_rcc=ioremap(PHY_RCC,4);
    if(NULL==virt_rcc)
    {
        printk("RCC映射失败\n");
        return -ENOMEM;
    }
    virt_gpioe=ioremap(PHY_GPIOE,sizeof(gpio_t));
    if(NULL==virt_gpioe)
    {
        printk("GPIOE映射失败");
        return -ENOMEM;
    }
    virt_gpiof=ioremap(PHY_GPIOF,sizeof(gpio_t));
    if(NULL==virt_gpiof)
    {
        printk("GPIOF映射失败\n");
        return -ENOMEM;
    }
    //对灯进行初始化
    //RCC使能
    *virt_rcc |= (0x3 << 4);
    //1.对LED1--->PE10初始化
   //设置PE10引脚为输出模式
    virt_gpioe->MODER &= (~(0x3 << 20));
    virt_gpioe->MODER |= (0x1 << 20);
    //设置PE10引脚默认为低电平
    virt_gpioe->ODR &= (~(0x1 << 10));
 
    //2.对LED2--->PF10初始化
    //设置PF10引脚为输出模式
    virt_gpiof->MODER &= (~(0x3 << 20));
    virt_gpiof->MODER |= (0x1 << 20);
    //设置PF10引脚默认为低电平
    virt_gpiof->ODR &= (~(0x1 << 10));
 
    //3.对LED3--->PE8初始化
    //设置PE8引脚为输出模式
    virt_gpioe->MODER &= (~(0x3 << 16));
    virt_gpioe->MODER |= (0x1 << 16);
    //设置PE8引脚默认为低电平
    virt_gpioe->ODR &= (~(0x1 << 8));
    return 0;
    ERR5:
        for(--i;i>0;i--)
        {
            device_destroy(cls,MKDEV(major,i));
        }
        class_destroy(cls);
    ERR4:
        cdev_del(cdev);
    ERR3:
        unregister_chrdev_region(MKDEV(major,minor),count);
    ERR2:
        kfree(cdev);
    ERR1:
        //返回错误码
        return -EIO;
}
//出口
static void __exit mycdev_exit(void)
{
    int i;
    //1。销毁设备节点信息
    for(i=0;i<count;i++)
    {
        device_destroy(cls,MKDEV(major,i));
    }
    //2.销毁目录信息
    class_destroy(cls);
    //3.驱动的注销
    cdev_del(cdev);
    //4.销毁设备号
    unregister_chrdev_region(MKDEV(major,minor),count);
    //5.释放cdev结构体
    kfree(cdev);
}
//指定入口地址
module_init(mycdev_init);
module_exit(mycdev_exit);
//指定出口地址
//许可证
MODULE_LICENSE("GPL");