驱动开发day9
目录
应用层写程序控制开发板6盏灯的亮灭，要求使用GPIO子系统
头文件：
驱动代码：
应用层代码：
驱动安装：
应用层使用gpio子系统控制灯的亮灭效果：
1.控制LED2熄灭：
2.控制LED6熄灭：
3.控制LED2重新点亮：
应用层写程序控制开发板6盏灯的亮灭，要求使用GPIO子系统
头文件：
#ifndef __MYLED_H_
#define __MYLED_H_
typedef enum {
LED1=1,
LED2,
LED3,
LED4,
LED5,
LED6
}LED;
#define LED_ON _IOW('a',1,int)
#define LED_OFF _IOW('a',0,int)
#endif驱动代码：
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include "myled.h"
#define CNAME "myled"
struct device_node *node;
struct property *pr;
struct gpio_desc *gpiono[5];
#if 1
unsigned int major = 0;//动态申请设备号
#else
unsigned int major = 500; //静态指定设备号
#endif
char kbuf[128]={};
int minor=0;
const int count=6;
struct class *cls;
struct device *dev;
struct cdev *cdev;
int mycdev_open(struct inode *inode,struct file *file)
{
return 0;
};
ssize_t mycdev_read(struct file *file, char __user *ubuf, size_t size, loff_t *loff)
{
int ret;
if(size>sizeof(kbuf))
size=sizeof(kbuf);
ret=copy_to_user(ubuf,kbuf,size);
if(ret)
{
printk("copy to user is error\n");
return -EIO;
}
return size;
}
ssize_t mycdev_write(struct file *file,const char __user *ubuf,size_t size,loff_t *loffs)
{
int ret;
if(size>sizeof(kbuf)) size=sizeof(kbuf);
ret=copy_from_user(kbuf,ubuf,size);
if(ret)
{
printk("copy from user is error\n");
return -EIO;
}
printk("copy from user kbuf=%s\n",kbuf);
return size;
}
long mycdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
int whitch;
int ret;
switch (cmd)
{
case LED_ON:
ret = copy_from_user(&whitch,(void*)arg,sizeof(int));
if(ret)
{
printk("copy from user led on!!!!\n");
return -EIO;
}
switch(whitch)
{
case LED1:
gpiod_set_value(gpiono[0],1);
break;
case LED2:
gpiod_set_value(gpiono[1],1);
break;
case LED3:
gpiod_set_value(gpiono[2],1);
break;
case LED4:
gpiod_set_value(gpiono[3],1);
break;
case LED5:
gpiod_set_value(gpiono[4],1);
break;
case LED6:
gpiod_set_value(gpiono[5],1);
break;
}
break;
case LED_OFF:
ret = copy_from_user(&whitch,(void*)arg,sizeof(int));
if(ret)
{
printk("copy from user led on!!!!\n");
return -EIO;
}
switch(whitch)
{
case LED1:
gpiod_set_value(gpiono[0],0);
break;
case LED2:
gpiod_set_value(gpiono[1],0);
break;
case LED3:
gpiod_set_value(gpiono[2],0);
break;
case LED4:
gpiod_set_value(gpiono[3],0);
break;
case LED5:
gpiod_set_value(gpiono[4],0);
break;
case LED6:
gpiod_set_value(gpiono[5],0);
break;
}
break;
}
return 0;
}
int mycdev_close(struct inode *inode,struct file *file)
{
return 0;
}
const struct file_operations fops={
.open=mycdev_open,
.read=mycdev_read,
.write=mycdev_write,
.unlocked_ioctl=mycdev_ioctl,
.release=mycdev_close,
};
static int __init mycdev_init(void)
{
int ret;
dev_t devno;
int i;
cdev=cdev_alloc();
if(NULL==cdev)
{
printk("cdev alloc error\n");
return -EIO;
goto ERR1;
}
cdev_init(cdev,&fops);
if(major>0)
{
ret=register_chrdev_region(MKDEV(major,minor),count,CNAME);
if(ret)
{
printk("register chrdev region is error\n");
ret= -ENOMEM;
goto ERR2;
}
}
else
{
ret=alloc_chrdev_region(&devno,0,count,CNAME);
if(ret)
{
printk("alloc chrdev region is error\n");
ret=-ENOMEM;
goto ERR2;
}
major = MAJOR(devno);
minor = MINOR(devno);
}
ret=cdev_add(cdev,MKDEV(major,minor),count);
if(ret)
{
printk("cdev add is error\n");
ret = -EIO;
goto ERR3;
}
cls=class_create(THIS_MODULE,CNAME);
if(IS_ERR(cls))
{
printk("class create is error\n");
ret= PTR_ERR(cls);
goto ERR4;
}
for(i=0;i0;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:
return -EIO;
}
static void __exit mycdev_exit(void)
{
int i;
for(i=0;i 应用层代码：
#include
#include
#include
#include
#include
#include
#include
#include
#include "myled.h"
int main(int argc, char const *argv[])
{
char buf[128]={};
int whitch;
int fd1,fd2,fd3,fd4,fd5,fd6;
fd1=open("/dev/myled0",O_RDWR);
if(fd1<0)
{
perror("open is error");
exit(1);
}
fd2=open("/dev/myled1",O_RDWR);
if(fd1<0)
{
perror("open is error");
exit(1);
}
fd3=open("/dev/myled2",O_RDWR);
if(fd1<0)
{
perror("open is error");
exit(1);
}
fd4=open("/dev/myled3",O_RDWR);
if(fd1<0)
{
perror("open is error");
exit(1);
}
fd5=open("/dev/myled4",O_RDWR);
if(fd1<0)
{
perror("open is error");
exit(1);
}
fd6=open("/dev/myled5",O_RDWR);
if(fd1<0)
{
perror("open is error");
exit(1);
}
while (1)
{
printf("请输入:0->LED OFF|1->LED ON\n>>");
fgets(buf,sizeof(buf),stdin);
buf[strlen(buf)-1]='\0';
if(buf[0]=='1')
{
printf("请选择要控制的LED灯:1->LED1 2->LED2 3->LED3 4->LED4 5->LED5 6->LED6\n>>");
scanf("%d",&whitch);
getchar();
if(whitch==1)
{
ioctl(fd1,LED_ON,&whitch);
}
if(whitch==2)
{
ioctl(fd2,LED_ON,&whitch);
}
if(whitch==3)
{
ioctl(fd3,LED_ON,&whitch);
}
if(whitch==4)
{
ioctl(fd4,LED_ON,&whitch);
}
if(whitch==5)
{
ioctl(fd5,LED_ON,&whitch);
}
if(whitch==6)
{
ioctl(fd6,LED_ON,&whitch);
}
}
else if(buf[0]=='0')
{
printf("请选择要控制的led灯:1->LED1 2->LED2 3->LED3 4->LED4 5->LED5 6->LED6\n>>");
scanf("%d",&whitch);
getchar();
if(whitch==1)
{
ioctl(fd1,LED_OFF,&whitch);
}
if(whitch==2)
{
ioctl(fd2,LED_OFF,&whitch);
}
if(whitch==3)
{
ioctl(fd3,LED_OFF,&whitch);
}
if(whitch==4)
{
ioctl(fd4,LED_OFF,&whitch);
}
if(whitch==5)
{
ioctl(fd5,LED_OFF,&whitch);
}
if(whitch==6)
{
ioctl(fd6,LED_OFF,&whitch);
}
}
else
{
printf("请重新输入!!!\n");
}
}
close(fd1);
close(fd2);
close(fd3);
close(fd4);
close(fd5);
close(fd6);
return 0;
}
驱动安装：
6盏灯全部点亮
应用层使用gpio子系统控制灯的亮灭效果：
