当前位置：首页 > news >正文

驱动day4work

news 2025/8/15 18:03:09

头文件

#ifndef __CKR_H__
#define __CKR_H__typedef struct
{unsigned int MODER;   // 00unsigned int OTYPER;  // 04unsigned int OSPEEDR; // 08unsigned int PUPDR;   // 0Cunsigned int IDR;     // 10unsigned int ODR;     // 14
} gpio_t;// GPIO口
#define PHY_GPIOB 0X50003000
#define PHY_GPIOE 0X50006000
#define PHY_GPIOF 0X50007000
// RCC 总线
#define PHY_RCC 0X50000A28// LED
#define LED_ON _IO('l', 1)
#define LED_OFF _IO('l', 0)#endif

应用程序

#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include "ckr.h"int main(int argc, char const *argv[])
{char buf[128] = {0};int led1 = open("/dev/myled0", O_RDWR);int led2 = open("/dev/myled1", O_RDWR);int led3 = open("/dev/myled2", O_RDWR);while (1){printf("\n请输入要操作的的灯(1-led1 2-led2 3-led3 4-退出)>>>");int a, b;scanf("%d", &a);if (a == 4){break;}printf("请输入操作指令(0-关灯 1-开灯)>>>");scanf("%d", &b);switch (a){case 1:if (b == 0){ioctl(led1, LED_OFF);}if (b == 1){ioctl(led1, LED_ON);}break;case 2:if (b == 0){ioctl(led2, LED_OFF);}if (b == 1){ioctl(led2, LED_ON);}break;case 3:if (b == 0){ioctl(led3, LED_OFF);}if (b == 1){ioctl(led3, LED_ON);}break;default:break;}}close(led1);close(led2);close(led3);return 0;
}

驱动程序

#include <linux/init.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/io.h>
#include <linux/device.h>
#include <linux/uaccess.h>
#include <linux/slab.h>
#include <linux/cdev.h>
#include "ckr.h"gpio_t *GPIOE;
gpio_t *GPIOF;
unsigned int *RCC;struct cdev *cdev;
struct class *cls;
struct device *dev;
unsigned int major = 500;
unsigned int minor = 0; // 次设备号的起始值
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;                 // 获取当前设备文件对应的设备号file->private_data = (void *)MINOR(a); // 将次设备号保存到当前文件的file结构中printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);return 0;
}// ioctrl
long mycdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{unsigned int a = (unsigned int)file->private_data;switch (a){case 0:if (cmd == LED_ON){GPIOE->ODR |= (0x1 << 10);}else if (cmd == LED_OFF){GPIOE->ODR &= (~(0x1 << 10));}break;case 1:if (cmd == LED_ON){GPIOF->ODR |= (0x1 << 10);}else if (cmd == LED_OFF){GPIOF->ODR &= (~(0x1 << 10));}break;case 2:if (cmd == LED_ON){GPIOE->ODR |= (0x1 << 8);}else if (cmd == LED_OFF){GPIOE->ODR &= (~(0x1 << 8));}break;default:break;}return 0;
}int mycdev_close(struct inode *inode, struct file *file)
{printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);return 0;
}
// 定义一个操作方法结构体变量并且初始化
struct file_operations fops = {.open = mycdev_open,.release = mycdev_close,.unlocked_ioctl = mycdev_ioctl,
};void myled_init(void)
{// 进行寄存器地址的映射-----------------------------------------------GPIOE = ioremap(PHY_GPIOE, 4);if (GPIOE == NULL){printk("映射物理内存失败%d\n", __LINE__);return -EFAULT;}GPIOF = ioremap(PHY_GPIOF, 4);if (GPIOF == NULL){printk("映射物理内存失败%d\n", __LINE__);return -EFAULT;}RCC = ioremap(PHY_RCC, 4);if (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(*RCC) |= (0X3 << 4); // rcc使能GPIOE->MODER &= (~(0x3 << 20));GPIOE->MODER |= (0x1 << 20);GPIOE->ODR &= (~(0x1 << 10));GPIOF->MODER &= (~(0x3 << 20));GPIOF->MODER |= (0x1 << 20);GPIOF->ODR &= (~(0x1 << 10));GPIOE->MODER &= (~(0x3 << 16));GPIOE->MODER |= (0x1 << 16);GPIOE->ODR &= (~(0x1 << 8));
}static int __init mycdev_init(void)
{int ret;// 1.申请对象空间 cdev_alloccdev = cdev_alloc();if (cdev == NULL){printk("申请对象空间失败\n");ret = -EFAULT;goto OUT1;}// 2.初始化对象  cdev_initcdev_init(cdev, &fops);// 3.申请设备号  register_chrdev_region()/alloc_chrdev_region()if (major == 0) // 动态申请{ret = alloc_chrdev_region(&devno, minor, 3, "mycdev");if (ret){printk("动态申请设备号失败\n");goto OUT2;}// 统一后面的操作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, "mycdev");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_add()ret = cdev_add(cdev, MKDEV(major, minor), 3);if (ret){printk("注册设备驱动对象失败\n");goto OUT3;}// 5.向上提交目录  class_create()cls = class_create(THIS_MODULE, "mycdev");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");// 6.向上提交设备信息 device_create()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("向上提交设备节点失败\n");ret = -PTR_ERR(dev);goto OUT5;}}printk("向上提交设备信息成功\n");myled_init();printk("led初始化成功\n");return 0;
OUT5:for (--i; i >= 0; i--) // 将提交成功的设备信息销毁{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)
{// 1.销毁设备信息  device_destroyint i;for (i = 0; i < 3; i++){device_destroy(cls, MKDEV(major, i));}// 2.销毁目录    class_destroyclass_destroy(cls);// 3.注销驱动对象  cdev_delcdev_del(cdev);// 4.释放设备号   unregister_chrdev_region()unregister_chrdev_region(MKDEV(major, minor), 3);// 5.释放对象空间   kfree()kfree(cdev);
}module_init(mycdev_init);
module_exit(mycdev_exit);
MODULE_LICENSE("GPL");

查看全文

http://www.lryc.cn/news/95864.html