内核驱动模块代码
#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/slab.h>
#include "fsmp157a_led_head.h"unsigned int *vir_gpioe_moder;
unsigned int *vir_gpioe_odr;
unsigned int *vir_gpiof_moder;
unsigned int *vir_gpiof_odr;
unsigned int *vir_rcc;char kbuf[128] = "";
//封装操作方法
//int (*open) (struct inode *, struct file *);
//ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
//ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
//int (*release) (struct inode *, struct file *);
//long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);int mycdev_open(struct inode *inode, struct file *file)
{int min = MINOR(inode->i_rdev);file->private_data = (void *)min;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)
{printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);return 0;
}ssize_t mycdev_write(struct file *fiile,const char *ubuf, size_t size, loff_t *lof)
{printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);int ret;//将用户空间的数据传递到内核ret = copy_from_user(kbuf, ubuf, size);if(ret){printk("copy_from_user is filed\n");return -EIO;}/*switch(kbuf[0]){//LED1case '1':switch(kbuf[1]){case '0'://关灯逻辑(*vir_gpioe_odr) &= (~(0x1 << 10));break;case '1'://开灯逻辑(*vir_gpioe_odr) |= (0x1 << 10);break;}break;//LED2case '2':switch(kbuf[1]){case '0'://关灯逻辑(*vir_gpiof_odr) &= (~(0x1 << 10));break;case '1'://开灯逻辑(*vir_gpiof_odr) |= (0x1 << 10);break;}break;//LED3case '3':switch(kbuf[1]){case '0'://关灯逻辑(*vir_gpioe_odr) &= (~(0x1 << 8));break;case '1'://开灯逻辑(*vir_gpioe_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;
}
//long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
long mycdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{// int which;// int ret;// ret = copy_from_user(&which , (void *) arg, 4);// if(ret)// {// printk("copy_from_user is filed\n");// return -EIO;// }int min = (int)file->private_data;switch(min){case 0:switch(cmd){case LED_OFF:(*vir_gpioe_odr) &= (~(0x1 << 10));break;case LED_ON:(*vir_gpioe_odr) |= (0x1 << 10);break;}break;case 1:switch(cmd){case LED_OFF:(*vir_gpiof_odr) &= (~(0x1 << 10));break;case LED_ON:(*vir_gpiof_odr) |= (0x1 << 10);break;}break;case 2:switch(cmd){case LED_OFF:(*vir_gpioe_odr) &= (~(0x1 << 8));break;case LED_ON:(*vir_gpioe_odr) |= (0x1 << 8);break;}break;}return 0;
}
//定义一个操作方法结构体对象
struct file_operations fos = {.open = mycdev_open,.read = mycdev_read,.write = mycdev_write,.release = mycdev_close,.unlocked_ioctl = mycdev_ioctl,};//定义变量,存放major
unsigned int major;
//定义变量,接收class_create()函数得到的对象指针
struct class *cls;
//定义变量,接收device_create()函数得到的对象指针
struct device *dev;//定义变量,主设备号,次设备号
unsigned int major=0;
unsigned int minor=0;
//定义变量,设备号
dev_t devnum;
//定义变量,存放申请类对象空间的首地址
struct cdev *cdev;
//定义变量,接收返回值
int ret;
//int __register_file(struct cdev *cdev, dev_t devnum, unsigned int major, unsigned int minor, struct class *cls, struct device *dev, struct file_operations *fos);
int __register_file(void);
//入口函数
static int __init mycdev_init(void)
{// __register_file(cdev, devnum, major, minor, cls, dev, &fos);__register_file();/*//注册设备驱动,申请0-255共256个资源(次设备号)major = register_chrdev(0, "mychardev", &fos);if(major < 0){printk("注册设备驱动失败\n");return major;}printk("注册设备驱动成功:major = %d\n", major);//向上提供目录//函数原型struct class *class_create(owner, name);//功能:向上提供目录信息,申请一个struct class类对象空间并初始化//参数1:owner:指向当前模块自身的一个指针,填写THIS_MODULE//参数2:name:向上提交的目录名//返回值:成功返回申请到的class对象的首地址,失败返回一个指向内核顶层4k空间的指针cls = class_create(THIS_MODULE, "mychrdev");if(IS_ERR(cls)){printk("向上提供目录失败\n");return -PTR_ERR(cls);}printk("向上提供目录成功\n");//向上提供设备节点信息//函数原型struct device *device_create(struct class *cls, struct device *parent, dev_t devt, void *drvdata, const char *fmt, ...);int i;for(i=0; i<3; i++){dev = device_create(cls, NULL, MKDEV(major, i), NULL, "myled%d", i);if(IS_ERR(dev)){printk("向上提供设备节点信息失败\n");return -PTR_ERR(dev);}}printk("向上提供设备节点信息成功\n");*///物理内存映射到虚拟地址//GOIOE_MODER寄存器地址映射vir_gpioe_moder = ioremap(PHY_GPIOE_MODER, 4);if(NULL == vir_gpioe_moder){printk("物理内存地址映射失败%d\n", __LINE__);return -EFAULT;}//GOIOE_ODR寄存器地址映射vir_gpioe_odr = ioremap(PHY_GPIOE_ODR, 4);if(NULL == vir_gpioe_odr){printk("物理内存地址映射失败%d\n", __LINE__);return -EFAULT;}//GOIOF_MODER寄存器地址映射vir_gpiof_moder = ioremap(PHY_GPIOF_MODER, 4);if(NULL == vir_gpiof_moder){printk("物理内存地址映射失败%d\n", __LINE__);return -EFAULT;}//GOIOF_ODR寄存器地址映射vir_gpiof_odr = ioremap(PHY_GPIOF_ODR, 4);if(NULL == vir_gpiof_odr){printk("物理内存地址映射失败%d\n", __LINE__);return -EFAULT;}//RCC_AHB4ENSETR寄存器地址映射vir_rcc = ioremap(PHY_RCC, 4);if(NULL == vir_rcc){printk("物理内存地址映射失败%d\n", __LINE__);return -EFAULT;}printk("物理内存地址映射成功\n");//寄存器初始化工作//RCC使能GPIOE/GPIOF组控制器(*vir_rcc) |= (0x3 << 4);return 0;
}//出口函数
static void __exit mycdev_exit(void)
{//取消内存映射iounmap(vir_gpioe_moder);iounmap(vir_gpioe_odr);iounmap(vir_gpiof_moder);iounmap(vir_gpiof_odr);iounmap(vir_rcc);//销毁设备节点信息int i;for(i=0; i<3; i++){device_destroy(cls, MKDEV(major, i));}//删除目录信息class_destroy(cls);//注销字符设备驱动对象cdev_del(cdev);//释放设备号unregister_chrdev_region(MKDEV(major, major), 3);//释放申请到的字符设备驱动对象空间kfree(cdev);//删除信息// //销毁设备节点信息// 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");}
//声明入口函数
module_init(mycdev_init);
//声明出口函数
module_exit(mycdev_exit);
//声明内核模块遵循GPL协议
MODULE_LICENSE("GPL");//注册设备驱动,创建设备文件
//int __register_file(struct cdev *cdev, dev_t devnum, unsigned int major, unsigned int minor, struct class *cls, struct device *dev, struct file_operations *fos)
int __register_file(void)
{//1.申请字符设备驱动对象空间cdev = cdev_alloc();if(NULL == cdev){printk("申请字符设备驱动对象空间失败\n");goto out1;}printk("申请字符设备驱动成功\n");//2.初始化对象 //函数原型: cdev_init(struct cdev *, const struct file_operations *);cdev_init(cdev, &fos);//3.申请设备号if(0 == major){ret = alloc_chrdev_region(&devnum, minor, 3, "mychrdev");if(ret){printk("申请设备号失败\n");goto out2;}major = MAJOR(devnum);minor = MINOR(devnum);printk("动态申请设备号成功\n");}else{ret = register_chrdev_region(MKDEV(major, minor), 3, "mychrdev");if(ret){printk("申请设备号失败\n");goto out2;}printk("静态申请设备号成功\n");}//4.注册设备驱动到内核ret = cdev_add(cdev, MKDEV(major, minor), 3);if(ret){printk("注册设备驱动到内核失败\n");goto out3;}printk("注册设备驱动到内核成功\n");//5.向上提交目录信息cls = class_create(THIS_MODULE, "mychrdev");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int i;for(i=0; i<3; i++){dev = device_create(cls, NULL, MKDEV(major, i), NULL, "mychrdev%d", i);if(IS_ERR(dev)){printk("向上提交设备节点信息失败\n");goto out5;}}printk("向上提交设备节点信息成功\n");return 0;out5://删除设备节点信息for(--i; i>=0; i--){device_destroy(cls, MKDEV(major, i));return -PTR_ERR(dev);}//删除设备目录class_destroy(cls);return -PTR_ERR(cls);out4://注销设备驱动cdev_del(cdev);out3://释放设备号unregister_chrdev_region(MKDEV(major, major), 3);out2://释放字符设备驱动对象空间kfree(cdev);out1:return ret;
}
应用层测试代码
#include <stdio.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <unistd.h>
#include <string.h>
#include <sys/ioctl.h>
#include "fsmp157a_led_head.h"int main(int argc, char const *argv[])
{char buf[128] = "";char filename[128] = "";printf("请输入操作的设备文件\n");fgets(filename, sizeof(filename), stdin);filename[strlen(filename) - 1] = '\0';int fd = open(filename, O_RDWR);if(fd < 0){printf("打开设备文件失败\n");return -1;}printf("打开设备文件成功\n");while(1){while(1){ioctl(fd, LED_ON);sleep(1);ioctl(fd, LED_OFF);sleep(1);}}return 0;
}
头文件
#ifndef __HEAD_H__
#define __HEAD_H__//GPIOE_MODER寄存器地址
#define PHY_GPIOE_MODER 0x50006000
//GPIOE_ODR寄存器地址
#define PHY_GPIOE_ODR 0X50006014//GPIOF_MODER寄存器地址
#define PHY_GPIOF_MODER 0X50007000
//GPIOF_ODR寄存器地址
#define PHY_GPIOF_ODR 0X50007014//RCC_AHB4ENSETR寄存器地址
#define PHY_RCC 0x50000A28//构建开关等的功能码
#define LED_ON _IO('l', 1)
#define LED_OFF _IO('l', 0)
#endif