驱动day4work
头文件
#ifndef __CKR_H__
#define __CKR_H__
typedef struct
{
unsigned int MODER; // 00
unsigned int OTYPER; // 04
unsigned int OSPEEDR; // 08
unsigned int PUPDR; // 0C
unsigned int IDR; // 10
unsigned 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
#include
#include
#include
#include
#include
#include
#include
#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
#include
#include
#include
#include
#include
#include
#include
#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_alloc
cdev = 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_init
cdev_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_destroy
int i;
for (i = 0; i < 3; i++)
{
device_destroy(cls, MKDEV(major, i));
}
// 2.销毁目录 class_destroy
class_destroy(cls);
// 3.注销驱动对象 cdev_del
cdev_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");