内核驱动模块代码
#include
#include
#include
#include
#include
#include
#include
#include
#include
#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])
{
//LED1
case '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;
//LED2
case '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;
//LED3
case '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
#include
#include
#include
#include
#include
#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