公司网站制作需要什么,最近三天国内重大新闻,网站开发用的软件,南通微信网站开发一、思维导图 二、通过字符设备驱动的分步实现编写LED驱动#xff0c;另外实现特备文件和设备的绑定
应用程序 test.c
#includestdlib.h
#includestdio.h
#include sys/types.h
#include sys/stat.h
#include sys/ioctl.h
#include…一、思维导图 二、通过字符设备驱动的分步实现编写LED驱动另外实现特备文件和设备的绑定
应用程序 test.c
#includestdlib.h
#includestdio.h
#include sys/types.h
#include sys/stat.h
#include sys/ioctl.h
#include fcntl.h
#includeunistd.h
#includestring.h
#include head.hint main(int argc, char const *argv[])
{char buf[128]{0};int a;int fdopen(/dev/mycdev0,O_RDWR);if(fd0){printf(打开设备文件失败\n);exit(-1);}while(1){//从终端读取printf(请输入要实现的功能 );printf(0(关灯) 1(开灯)\n);printf(请输入);scanf(%d,a);switch(a){case 1:ioctl(fd,LED_ON);break;case 0:ioctl(fd,LED_OFF);break;}}close(fd);return 0;
}
头文件 head.h
#ifndef __HEAD_H__
#define __HEAD_H__
typedef struct
{unsigned int MODER;unsigned int OTYPER;unsigned int OSPEEDR;unsigned int PUPDR;unsigned int IDR;unsigned int ODR;
}gpio_t;
#define PHY_LED1_ADDR 0X50006000
#define PHY_LED2_ADDR 0X50007000
#define PHY_LED3_ADDR 0X50006000
#define PHY_RCC_ADDR 0X50000A28
// 构建开灯关灯的功能码
#define LED_ON _IO(l, 1)
#define LED_OFF _IO(l, 0)
#endif驱动程序 mycdev.c
#include linux/init.h
#include linux/module.h
#includelinux/fs.h
#includelinux/device.h
#includelinux/cdev.h
#includelinux/slab.h
#includelinux/io.h
#includelinux/uaccess.h
#include head.hstruct cdev *cdev;
unsigned int major0;
unsigned int minor0;
dev_t devno;char kbuf[128] {0};
gpio_t *vir_led1;
gpio_t *vir_led2;
gpio_t *vir_led3;
unsigned int *vir_rcc;
struct class *cls;
struct device *dev;int mycdev_open(struct inode *inode, struct file *file)
{//获取打开的文件的次设备号int min MINOR(inode-i_rdev);file-private_data (void *)min;printk(%s:%s:%d\n,__FILE__,__func__,__LINE__);return 0;
}
long mycdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{//获取文件的次设备号int min (int)file-private_data;switch (min){case 0: // 开灯switch (cmd){case LED_ON: // LED1vir_led1-ODR | (0X1 10); //LED开break;case LED_OFF:vir_led1-ODR (~(0X1 10));break;}break;case 1: // 关灯switch (cmd){case LED_ON: // LED1vir_led2-ODR | (0X1 10);break;case LED_OFF:vir_led2-ODR (~(0X1 10));break;}break;case 2:switch (cmd){case LED_ON: // LED1vir_led3-ODR | (0X1 8);break;case LED_OFF:vir_led3-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;
}
//定义操作方法结构体变量并赋值
struct file_operations fops{.open mycdev_open,.unlocked_ioctl mycdev_ioctl,.release mycdev_close,
};
int all_led_init(void)
{// 寄存器地址的映射vir_led1 ioremap(PHY_LED1_ADDR, sizeof(gpio_t));if (vir_led1 NULL){printk(ioremap filed:%d\n, __LINE__);return -ENOMEM;}vir_led2 ioremap(PHY_LED2_ADDR, sizeof(gpio_t));if (vir_led2 NULL){printk(ioremap filed:%d\n, __LINE__);return -ENOMEM;}vir_led3 vir_led1;vir_rcc ioremap(PHY_RCC_ADDR, 4);if (vir_rcc NULL){printk(ioremap filed:%d\n, __LINE__);return -ENOMEM;}printk(物理地址映射成功\n);// 寄存器的初始化// rcc(*vir_rcc) | (3 4);// led1vir_led1-MODER (~(3 20));vir_led1-MODER | (1 20);vir_led1-ODR (~(1 10));// led2vir_led2-MODER (~(3 20));vir_led2-MODER | (1 20);vir_led2-ODR (~(1 10));// led3vir_led3-MODER (~(3 16));vir_led1-MODER | (1 16);vir_led1-ODR (~(1 8));printk(寄存器初始化成功\n);return 0;
}
static int __init mycdev_init(void)
{//1.申请一个对象空间cdev_allocint ret;cdev cdev_alloc();if (NULL cdev){printk(申请字符设备驱动对象失败\n);ret -EFAULT;goto out1;}printk(字符设备驱动对象申请成功\n);//2.初始化对象cdev_inicdev_init(cdev,fops);//3.申请设备号register_chrdev_region()/alloc_chrdev_region()if(0 major){ret alloc_chrdev_region(devno,minor,3,mychrdev);if(ret){printk(动态申请设备号失败\n);goto out2;}majorMAJOR(devno); //根据设备号获取主设备号minorMINOR(devno); //根据设备号获取次设备号}else //静态制定设备号{retregister_chrdev_region(MKDEV(major,minor),3,mychrdev);if(ret){printk(静态指定设备号失败\n);goto out2;}}printk(设备号申请成功\n);//4.注册驱动对象 cdev_addret cdev_add(cdev,MKDEV(major,minor),3);if(ret){printk(注册字符设备驱动对象失败\n);goto out3;}printk(注册字符设备驱动对象成功\n);//5.向上提交目录 class_createcls 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 device_createint i;for(i0;i3;i){dev device_create(cls,NULL,MKDEV(major,i),NULL,mycdev%d,i);if(IS_ERR(dev)){printk(向上提交设备节点失败\n);goto out5;}}printk(向上提交设备节点信息成功\n);// 寄存器映射以及初始化all_led_init();return 0;
out5://奖提交成功的节点信息释放for(--i;i0;i--){device_destroy(cls,MKDEV(major,i));}//销毁目录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)
{// 取消地址映射iounmap(vir_led1);iounmap(vir_led2);iounmap(vir_rcc);//1.销毁设备节点信息int i;for(i0;i3;i){device_destroy(cls,MKDEV(major,i));}//2.销毁目录class_destroy(cls);//3.注销字符设备驱动对象cdev_del(cdev);//4.释放设备号unregister_chrdev_region(MKDEV(major,minor),3);//5.释放申请到的字符设备驱动对象空间kfree(cdev);
}
module_init(mycdev_init);
module_exit(mycdev_exit);
MODULE_LICENSE(GPL);
Makefile
modname ? demo
arch ? arm
ifeq ($(arch),arm) #通过命令行传过来的架构决定怎么编译
#KERBELDIR保存开发板内核源码路径
KERNELDIR : /home/ubuntu/FSMP1A/linux-stm32mp-5.10.61-stm32mp-r2-r0/linux-5.10.61
else
#保存UBUNTU内核源码路径
KERNELDIR : /lib/modules/$(shell uname -r)/build
endif#PWD保存当前内核模块的路径
PWD : $(shell pwd)
all:
#make modules是模块化编译命令
#make -C $(KERNLEDIR) 执行make之前先切换到KERNELDIR对应的路径
#M$(PWD)表示进行模块化编译的路径是PWD保存的路径make -C $(KERNELDIR) M$(PWD) modules
clean:
#编译清除make -C $(KERNELDIR) M$(PWD) clean
#将obj-m保存的文件单独链接为内核模块
obj-m : $(modname).o效果实现
