驱动（分步注册驱动设备）
头文件
#ifndef __LED_H__
#define __LED_H__
#define PHY_LED1_MODER 0X50006000
#define PHY_LED1_ODR 0X50006014
#define PHY_LED1_RCC 0X50000A28
#define PHY_LED2_MODER 0X50007000
#define PHY_LED2_ODR 0X50007014
#define PHY_LED2_RCC 0X50000A28
#define PHY_LED3_MODER 0X50006000
#define PHY_LED3_ODR 0X50006014
#define PHY_LED3_RCC 0X50000A28
//风扇
#define PHY_FAN_MODER 0X50006000
#define PHY_FAN_ODR 0X50006014
#define PHY_FAN_RCC 0X50000A28
//蜂鸣器
#define PHY_BUZZER_MODER 0X50003000
#define PHY_BUZZER_ODR 0X50003014
#define PHY_BUZZER_RCC 0X50000A28
//马达
#define PHY_MOTOR_MODER 0X50007000
#define PHY_MOTOR_ODR 0X50007014
#define PHY_MOTOR_RCC 0X50000A28
//功能码
#define LED_ON _IO('l',1)
#define LED_OFF _IO('l',0)
#define FAN_ON _IO('f',1)
#define FAN_OFF _IO('f',0)
#define BUZZER_ON _IO('b',1)
#define BUZZER_OFF _IO('b',0)
#define MOTOR_ON _IO('m',1)
#define MOTOR_OFF _IO('m',0)
#endif驱动代码
#include
#include
#include
#include
#include
#include
#include
#include "head.h"
unsigned int *vir_led1_moder;
unsigned int *vir_led1_odr;
unsigned int *vir_led1_rcc;
unsigned int *vir_led2_moder;
unsigned int *vir_led2_odr;
unsigned int *vir_led2_rcc;
unsigned int *vir_led3_moder;
unsigned int *vir_led3_odr;
unsigned int *vir_led3_rcc;
struct cdev* cdev;
struct class* cls;
struct device* dev;
unsigned int major = 500;
unsigned int minor = 0;
dev_t devno;
char kbuf[128] = {0};
// 封装操作方法
int mycdev_open(struct inode *inode, struct file *file)
{
int a = inode->i_rdev;
file->private_data = (void *)MINOR(a);
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)
{
long ret;
if(size>sizeof(kbuf)){
size = sizeof(kbuf);
}
printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);
ret = copy_to_user(ubuf, kbuf, size);
if (ret)
{
printk("copy_to_user filed\n");
return -EIO;
}
return 0;
}
ssize_t mycdev_write(struct file *file, const char *ubuf, size_t size, loff_t *lof)
{
if(size>sizeof(kbuf)){
size = sizeof(kbuf);
}
long ret;
printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);
ret = copy_from_user(kbuf, ubuf, size);
if (ret)
{
printk("copy_from_user filed\n");
return -EIO;
}
return 0;
}
int mycdev_close(struct inode *inode, struct file *file)
{
printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);
return 0;
}
long mychrdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{ unsigned int a;
printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);
a = (unsigned int)file->private_data;
switch(a)
{
case 0:
if(cmd == LED_ON){
*vir_led1_odr |= (0x1 << 10);
}
else{
*vir_led1_odr &= (~(0x1 << 10));
}
break;
case 1:
if(cmd == LED_ON){
*vir_led2_odr |= (0x1 << 10);
}
else{
*vir_led2_odr &= (~(0x1 << 10));
}
break;
case 2:
if(cmd == LED_ON){
*vir_led3_odr |= (0x1 << 8);
}
else{
*vir_led3_odr &= (~(0x1 << 8));
}
break;
}
return 0;
}
//对设备文件进行操作的结构体
struct file_operations fops = {
.open = mycdev_open,//打开
.read = mycdev_read,//读
.write = mycdev_write,//写
.unlocked_ioctl = mychrdev_ioctl,//硬件功能的选择
.release = mycdev_close,//关闭
};
int led_init(void)
{
vir_led1_moder = ioremap(PHY_LED1_MODER, 4);
if (vir_led1_moder == NULL)
{
printk("映射物理内存失败%d\n", __LINE__);
return -EFAULT;
}
vir_led1_odr = ioremap(PHY_LED1_ODR, 4);
if (vir_led1_odr == NULL)
{
printk("映射物理内存失败%d\n", __LINE__);
return -EFAULT;
}
vir_led1_rcc = ioremap(PHY_LED1_RCC, 4);
if (vir_led1_rcc == NULL)
{
printk("映射物理内存失败%d\n", __LINE__);
return -EFAULT;
}
(*vir_led1_rcc) |= (0x1 << 4);
(*vir_led1_moder) &= (~(0x3 << 20));
(*vir_led1_moder) |= (0x1 << 20);
(*vir_led1_odr) &= (~(0x1 << 10));
vir_led2_moder = ioremap(PHY_LED2_MODER, 4);
if (vir_led2_moder == NULL)
{
printk("映射物理内存失败%d\n", __LINE__);
return -EFAULT;
}
vir_led2_odr = ioremap(PHY_LED2_ODR, 4);
if (vir_led2_odr == NULL)
{
printk("映射物理内存失败%d\n", __LINE__);
return -EFAULT;
}
vir_led2_rcc = ioremap(PHY_LED2_RCC, 4);
if (vir_led2_rcc == NULL)
{
printk("映射物理内存失败%d\n", __LINE__);
return -EFAULT;
}
(*vir_led2_rcc) |= (0x1 << 5);
(*vir_led2_moder) &= (~(0x3 << 20));
(*vir_led2_moder) |= (0x1 << 20);
(*vir_led2_odr) &= (~(0x1 << 10));
vir_led3_moder = ioremap(PHY_LED3_MODER, 4);
if (vir_led3_moder == NULL)
{
printk("映射物理内存失败%d\n", __LINE__);
return -EFAULT;
}
vir_led3_odr = ioremap(PHY_LED3_ODR, 4);
if (vir_led3_odr == NULL)
{
printk("映射物理内存失败%d\n", __LINE__);
return -EFAULT;
}
vir_led3_rcc = ioremap(PHY_LED3_RCC, 4);
if (vir_led3_rcc == NULL)
{
printk("映射物理内存失败%d\n", __LINE__);
return -EFAULT;
}
printk("映射物理内存成功\n");
// 硬件寄存器的初始化
(*vir_led3_rcc) |= (0x1 << 4);
(*vir_led3_moder) &= (~(0x3 << 16));
(*vir_led3_moder) |= (0x1 << 16);
(*vir_led3_odr) &= (~(0x1 << 8));
return 0;
}
static int __init mycdev_init(void)
{
//************分布注册驱动设备*********************
int ret;
//1、为驱动对象申请空间
cdev = cdev_alloc();
if(cdev == NULL){
printk("申请空间失败\n");
ret = -EFAULT;
goto OUT1;
}
//2、对象的初始化
cdev_init(cdev,&fops);
//3、申请设备号
if(major == 0)//动态
{
ret = alloc_chrdev_region(&devno,minor,3,"mychrdev");
if(ret){
printk("动态申请设备号失败\n");
goto OUT2;
}
//统一后边的操作
major = MAJOR(devno);//根据设备号获取主设备号
minor = MINOR(devno);
}
else{
ret = register_chrdev_region(MKDEV(major,minor),3,"mychrdev");
if(ret){
printk("静态申请设备号失败\n");
goto OUT2;
}
}
//4、注册驱动对象
if(cdev_add(cdev,MKDEV(major,minor),3)){
printk("注册驱动对象失败\n");
goto OUT3;
}
//************自动申请设备节点*********************
//1、向上提交目录
cls = class_create(THIS_MODULE, "mychrdev");
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");
// 2、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("提交设备信息失败\n");
ret = -PTR_ERR(dev);
goto OUT5;
}
}
printk("提交设备信息成功\n");
led_init();
return 0;
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)
{
iounmap(vir_led1_moder);
iounmap(vir_led1_odr);
iounmap(vir_led1_rcc);
iounmap(vir_led2_moder);
iounmap(vir_led2_odr);
iounmap(vir_led2_rcc);
iounmap(vir_led3_moder);
iounmap(vir_led3_odr);
iounmap(vir_led3_rcc);
printk("取消映射成功\n");
//1.销毁设备信息
int i;
for(i=0;i<3;i++){
device_destroy(cls,MKDEV(major,i));
}
//2.销毁目录信息
class_destroy(cls);
//3.注销驱动对象
cdev_del(cdev);
//4.释放设备号
unregister_chrdev_region(MKDEV(major,minor),3);
//5.释放对象空间
kfree(cdev);
}
// 用于向内核报备当前内核模块入口函数的地址
module_init(mycdev_init);
// 用于向内核报备当前内核模块出口函数的地址
module_exit(mycdev_exit);
// 生命当前内核模块遵循GPL协议
MODULE_LICENSE("GPL");
应用程序
#include
#include
#include
#include
#include
#include
#include
#include
#include "head.h"
int main(int argc, char const *argv[])
{
char buf[128] = {0};
int led1_fd, led2_fd, led3_fd;
// 打开led1设备文件
led1_fd = open("/dev/mychrdev0", O_RDWR);
if (led1_fd < 0)
{
printf("打开led1设备文件失败\n");
exit(-1);
}
// 打开led2设备文件
led2_fd = open("/dev/mychrdev1", O_RDWR);
if (led2_fd < 0)
{
printf("打开led2设备文件失败\n");
exit(-1);
}
// 打开led3设备文件
led3_fd = open("/dev/mychrdev2", O_RDWR);
if (led3_fd < 0)
{
printf("打开myled3设备文件失败\n");
exit(-1);
}
int a, b;
while (1)
{
printf("请选择要控制的器件: 1(led灯1) 2 (led灯2) 3 (led灯3) ");
scanf("%d", &a);
printf("请输入指令:0(关闭) 1 (打开)");
scanf("%d", &b);
switch (b)
{
case 1:
switch (a)
{
case 1:
ioctl(led1_fd, LED_ON);
break;
case 2:
ioctl(led2_fd, LED_ON);
break;
case 3:
ioctl(led3_fd, LED_ON);
break;
}
break;
case 0:
switch (a)
{
case 1:
ioctl(led1_fd, LED_OFF);
break;
case 2:
ioctl(led2_fd, LED_OFF);
break;
case 3:
ioctl(led3_fd, LED_OFF);
break;
}
break;
}
}
close(led1_fd);
close(led2_fd);
close(led3_fd);
return 0;
}