head.h
#ifndef __HEAD_H__
#define __HEAD_H__
#define PHY_RCC 0X50000A28
#define PHY_GPIOE 0X50006000
#define PHY_GPIOE_ODR 0X50006014
#define PHY_GPIOF 0X50007000
#define PHY_GPIOF_ODR 0X50007014
#endif // MACRO
fun.c
#include
#include
#include
#include
#include
#include
#include
int main(int argc, char const *argv[])
{
/* code */
char buf[128] = {0};
printf("调用open\n");
int fd = open ("/dev/mycdev",O_RDWR);
if(fd < 0)
{
printf("打开设备文件失败\n");
exit(-1);
}
while(1)
{
printf("请输入要点亮的灯号(1-3)及操作(0[灭]、1[亮])[exit退出程序]:");
fgets(buf,sizeof(buf),stdin);
buf[strlen(buf)-1] = '\0';
write(fd,buf,sizeof(buf));
if(!strcmp(buf,"exit")) break;
}
printf("调用close\n");
close (fd);
return 0;
}
mycdev.c
#include
#include
#include
#include
#include "head.h"
unsigned int major;
char kbuf[128] = {0};
unsigned int *vir_moder;
unsigned int *vir_odr;
unsigned int *vir_rcc;
int mycdev_open(struct inode *inode,struct file *file)
{
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__);
if(copy_to_user(ubuf,kbuf,size))
{
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)
{
unsigned int pin;
printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
if(copy_from_user(kbuf,ubuf,size))
{
printk("copy_to_user filed\n");
return -EIO;
}
switch(kbuf[0])
{
case '1':
pin = 10;
vir_odr=ioremap(PHY_GPIOE_ODR,4);
if(vir_odr==NULL)
{
printk("映射物理内存失败%d\n",__LINE__);
return -EFAULT;
}
break;
case '2':
pin = 10;
vir_odr=ioremap(PHY_GPIOF_ODR,4);
if(vir_odr==NULL)
{
printk("映射物理内存失败%d\n",__LINE__);
return -EFAULT;
}
break;
case '3':
pin = 8;
vir_odr=ioremap(PHY_GPIOE_ODR,4);
if(vir_odr==NULL)
{
printk("映射物理内存失败%d\n",__LINE__);
return -EFAULT;
}
break;
default:
printk("语法错误,请重新输入>>>");
return -1;
}
if(kbuf[1] == '0')
{
//关灯逻辑
(*vir_odr) &= (~(0X1<>>");
return -1;
}
return 0;
}
int mycdev_close(struct inode *inode,struct file *file)
{
printk("%s:%s:%d\n",__FILE__,__func__,__LINE__);
return 0;
}
struct file_operations fops={
.open = mycdev_open,
.release = mycdev_close,
.read = mycdev_read,
.write = mycdev_write,
};
void GPIO_INIT(unsigned int gpio,unsigned int pin)
{
//进行寄存器地址的映射
vir_moder=ioremap(gpio,4);
if(vir_moder==NULL)
{
printk("映射物理内存失败%d\n",__LINE__);
return;
}
vir_rcc=ioremap(PHY_RCC,4);
if(vir_rcc==NULL)
{
printk("映射物理内存失败%d\n",__LINE__);
return;
}
if(gpio == PHY_GPIOE)
{
vir_odr=ioremap(PHY_GPIOE_ODR,4);
if(vir_odr==NULL)
{
printk("映射物理内存失败%d\n",__LINE__);
return;
}
(*vir_rcc)|=(0X1<<4);//rcc使能GPIOE组
}
else if(gpio == PHY_GPIOF)
{
vir_odr=ioremap(PHY_GPIOF_ODR,4);
if(vir_odr==NULL)
{
printk("映射物理内存失败%d\n",__LINE__);
return;
}
(*vir_rcc)|=(0X1<<5);//rcc使能GPIOF组
}
printk("映射物理内存成功\n");
//硬件寄存器的初始化
(*vir_moder) &= (~(0X3 << pin*2));//设置为输出
(*vir_moder) |= (0X1 << pin*2);
(*vir_odr) &= (~(0X1 << pin));//输出低电平
printk("硬件寄存器初始化成功\n");
}
static int __init mycdev_init(void)
{
major = register_chrdev(0,"mycdev",&fops);
if(major < 0)
{
printk("注册失败\n");
}
printk("注册成功major = %d\n",major);
GPIO_INIT(PHY_GPIOE,10);
GPIO_INIT(PHY_GPIOF,10);
GPIO_INIT(PHY_GPIOE,8);
return 0;
}
static void __exit mycdev_exit(void)
{
unregister_chrdev(major,"mycdev");
printk("出口函数\n");
}
module_init(mycdev_init);
module_exit(mycdev_exit);
MODULE_LICENSE("GPL");
Makefile
modname ?= mycdev
arch ?= arm
ifeq ($(arch),arm)
KERNELDIR:= /home/ubuntu/13_UBOOT/linux-stm32mp-5.10.61-stm32mp-r2-r0/linux-5.10.61
else
KERNELDIR:=/lib/modules/$(shell uname -r)/build/
endif
PWD:=$(shell pwd)
all:
make -C $(KERNELDIR) M=$(PWD) modules
clean:
make -C $(KERNELDIR) M=$(PWD) clean
obj-m:=$(modname).o