驱动开发 day4 (led灯组分块驱动)

//编译驱动(注意Makefile的编译到移植到开发板的内核)

        make arch=arm

//清除编译生成文件

        make clean

//安装驱动

        insmod mycdev.ko

//卸载驱动

        rmmod mycdev

//编译fun.c 函数(用到交叉工具编译)

        arm-linux-gnueabihf-gcc fun.c

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

// 功能码
#define LED_ON _IOW('1', 1, int)
#define LED_OFF _IOW('1', 0, int)

#endif // MACRO

 mycdev.c

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include "head.h"

struct cdev *cdev;
struct class *cls;
struct device *dev;

char kbuf[128] = {0};
unsigned int major = 500;
unsigned int minor = 0; // 次设备号的起始值
dev_t devnum;

gpio_t *vir_led1;
gpio_t *vir_led2;
gpio_t *vir_led3;
unsigned int *vir_rcc;
// 定义一个自旋锁
spinlock_t lock;

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;
}

long mycdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	unsigned int which;
	which = (unsigned int)file->private_data;

	// copy_from_user(&which,(void *)arg,4);
	// 上锁
	spin_lock(&lock);
	switch (cmd)
	{
	case LED_ON:
		switch (which)
		{
		case 0:							  // LED1
			vir_led1->ODR |= (0x1 << 10); // LED1开灯
			break;
		case 1:							  // LED2
			vir_led2->ODR |= (0x1 << 10); // LED2开灯
			break;
		case 2:							 // LED3
			vir_led3->ODR |= (0x1 << 8); // LED3开灯
			break;
		}
		break;
	case LED_OFF:
		switch (which)
		{
		case 0:
			vir_led1->ODR &= (~(0X1 << 10));
			break;
		case 1:
			vir_led2->ODR &= (~(0X1 << 10));
			break;
		case 2:
			vir_led3->ODR &= (~(0X1 << 8));
			break;
		}
		break;
	}
	// 解锁
	spin_unlock(&lock);
	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,
	.release = mycdev_close,
	.unlocked_ioctl = mycdev_ioctl,
};

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);
	// led1
	vir_led1->MODER &= (~(3 << 20));
	vir_led1->MODER |= (1 << 20);
	vir_led1->ODR &= (~(1 << 10));
	// led2
	vir_led2->MODER &= (~(3 << 20));
	vir_led2->MODER |= (1 << 20);
	vir_led2->ODR &= (~(1 << 10));
	// led3
	vir_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)
{
	int ret, i;
	// 初始化上锁
	spin_lock_init(&lock);

	// 1.申请对象空间
	cdev = cdev_alloc();
	if (NULL == cdev)
	{
		printk("wangsong申请对象空间失败\n");
		ret = -EFAULT;
		goto OUT1;
	}
	printk("wangsong申请对象空间成功\n");

	// 2.初始化对象
	cdev_init(cdev, &fops);
	printk("wangsong初始化对象成功\n");

	// 3.申请设备号
	if (0 == major)
	{
		ret = alloc_chrdev_region(&devnum, minor, 3, "wangsong");
		if (ret)
		{
			printk("wangsong动态申请设备号失败\n");
			goto OUT2;
		}
		major = MAJOR(devnum);
		minor = MINOR(devnum);
	}
	else
	{
		ret = register_chrdev_region(MKDEV(major, minor), 3, "wangsong");
		if (ret)
		{
			printk("wangsong静态申请设备号失败\n");
			goto OUT2;
		}
	}
	printk("wangsong申请设备号成功\n");

	// 4.注册驱动对象
	ret = cdev_add(cdev, MKDEV(major, minor), 3);
	if (ret)
	{
		printk("wangsong注册驱动对象失败\n");
		goto OUT3;
	}
	printk("wangsong注册驱动对象成功\n");

	// 5.向上提交目录
	cls = class_create(THIS_MODULE, "wangsong");
	if (IS_ERR(cls))
	{
		printk("wangsong向上提交目录失败\n");
		goto OUT4;
	}
	printk("wangsong向上提交目录成功\n");

	// 6.向上提交设备信息

	for (i = 0; i < 3; i++)
	{
		dev = device_create(cls, NULL, MKDEV(major, i), NULL, "wangsong%d", i);
		if (IS_ERR(dev))
		{
			printk("wangsong向上提交设备节点失败\n");
			ret = -PTR_ERR(dev);
			goto OUT5;
		}
	}
	printk("wangsong向上提交设备节点成功\n");
	// 寄存器映射以及初始化
	all_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)
{
	int i;

	// 取消地址映射
	iounmap(vir_led1);
	iounmap(vir_led2);
	iounmap(vir_rcc);
	// 1.销毁设备信息
	for (i = 0; i < 3; i++)
	{
		device_destroy(cls, MKDEV(major, i));
		printk("wangsong销毁设备信息成功\n");
	}
	// 2.销毁目录
	class_destroy(cls);
	printk("wangsong销毁目录成功\n");
	// 3.注销驱动对象
	cdev_del(cdev);
	printk("wangsong注销驱动对象成功\n");
	// 4.释放设备号
	unregister_chrdev_region(MKDEV(major, minor), 3);
	printk("wangsong释放设备号成功\n");
	// 5.释放对象空间
	kfree(cdev);
	printk("wangsong释放对象空间成功\n");
}

module_init(mycdev_init);

module_exit(mycdev_exit);

MODULE_LICENSE("GPL");

fun.c

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include "head.h"

int main(int argc, char const *argv[])
{
	/* code */
	int a, b;
	char buf[128] = {0};
	printf("调用open\n");
	int fd0 = open("/dev/wangsong0", O_RDWR);
	if (fd0 < 0)
	{
		printf("打开设备文件失败\n");
		exit(-1);
	}
	int fd1 = open("/dev/wangsong1", O_RDWR);
	if (fd1 < 0)
	{
		printf("打开设备文件失败\n");
		exit(-1);
	}
	int fd2 = open("/dev/wangsong2", O_RDWR);
	if (fd2 < 0)
	{
		printf("打开设备文件失败\n");
		exit(-1);
	}

	while (1)
	{
		// 从终端读取
		printf("请输入要点亮的灯号(1-3)+操作(0[灭]、1[亮])[exit退出程序]:");
		fgets(buf, sizeof(buf), stdin);
		buf[strlen(buf) - 1] = '\0';
		if (!strcmp(buf, "exit"))
			break;

		a = (int)buf[1] - 48;
		b = (int)buf[0] - 48;

		printf("a=%d,b=%d", a, b);
		if (a == 1)
		{
			switch (b)
			{
			case 1:
				if (ioctl(fd0, LED_ON, &b))
				{
					printf("开灯失败\n");
				}
				break;
			case 2:
				if (ioctl(fd1, LED_ON, &b))
				{
					printf("开灯失败\n");
				}
				break;
			case 3:
				if (ioctl(fd2, LED_ON, &b))
				{
					printf("开灯失败\n");
				}
				break;
			default:
				printf("格式错误请重新输入>>>\n");
			}
		}
		else
		{
			switch (b)
			{
			case 1:
				if (ioctl(fd0, LED_OFF, &b))
				{
					printf("关灯失败\n");
				}
				break;
			case 2:
				if (ioctl(fd1, LED_OFF, &b))
				{
					printf("关灯失败\n");
				}
				break;
			case 3:
				if (ioctl(fd2, LED_OFF, &b))
				{
					printf("关灯失败\n");
				}
				break;
			default:
				printf("格式错误请重新输入>>>\n");
			}
		}
	}
	printf("调用close\n");
	close(fd0);
	close(fd1);
	close(fd2);

	return 0;
}

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