驱动 课后作业
#include
#include
#include
#include
#include
#include "led.h"
unsigned int major;
char kbuf[128] = "";
unsigned int *vir_led1_moder;
unsigned int *vir_led1_odr;
unsigned int *vir_led2_moder;
unsigned int *vir_led2_odr;
// unsigned int *vir_led3_moder;
// unsigned int *vir_led3_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 __user *ubuf, size_t size, loff_t *offs)
{
// 向用户拷贝
int ret;
// 如果用户想写的大小大于内核的内存大小，更正用户写的大小
if (size > sizeof(kbuf))
size = sizeof(kbuf);
ret = copy_to_user(ubuf, kbuf, size);
if (ret) // 成功返回0，失败返回未拷贝的字节的个数
{
printk("copy to user filed\n");
return -EIO;
}
printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);
return 0;
}
ssize_t mycdev_write(struct file *file, const char __user *ubuf, size_t size, loff_t *off)
{
// 从用户拷贝
int ret;
if (size > sizeof(kbuf))
size = sizeof(kbuf);
ret = copy_from_user(kbuf, ubuf, size);
if (ret)
{
printk("copy from user filed\n");
return -EIO;
}
printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);
// 根据用户空间发送来的指令实现灯的亮灭控制
if (kbuf[0] == '1') // led1亮
{
(*vir_led1_odr) |= (0x1 << 10);
(*vir_led2_odr) |= (0x1 << 10);
(*vir_led1_odr) |= (0x1 << 8);
}
else if (kbuf[0] == '0') // led1灭
{
(*vir_led1_odr) &= (~(0x1 << 10));
(*vir_led2_odr) &= (~(0x1 << 10));
(*vir_led1_odr) &= (~(0x1 << 8));
}
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初始化
struct file_operations fops = {
.open = mycdev_open,
.read = mycdev_read,
.write = mycdev_write,
.release = mycdev_close,
};
static int __init mycdev_init(void)
{
// 字符设备驱动注册
major = register_chrdev(0, "mycdev", &fops);
if (major < 0)
{
printk("字符设备驱动注册失败\n");
return major;
}
printk("字符设备驱动注册成功 major=%d\n", major);
// LED相关寄存器地址映射
vir_led1_moder = ioremap(PHY_led1_MODER, 4); // 4 32字节
if (vir_led1_moder == NULL)
{
printk("物理内存映射失败\n");
return -EFAULT;
}
vir_led2_moder = ioremap(PHY_led2_MODER, 4); // 4 32字节
if (vir_led2_moder == NULL)
{
printk("物理内存映射失败\n");
return -EFAULT;
}
// vir_led3_moder = ioremap(PHY_led2_MODER, 4); // 4 32字节
// if (vir_led3_moder == NULL)
// {
// printk("物理内存映射失败\n");
// return -EFAULT;
// }
vir_led1_odr = ioremap(PHY_led1_ODR, 4); // 4 32字节
if (vir_led1_odr == NULL)
{
printk("物理内存映射失败\n");
return -EFAULT;
}
vir_led2_odr = ioremap(PHY_led2_ODR, 4); // 4 32字节
if (vir_led2_odr == NULL)
{
printk("物理内存映射失败\n");
return -EFAULT;
}
// vir_led3_odr = ioremap(PHY_led2_ODR, 4); // 4 32字节
// if (vir_led3_odr == NULL)
// {
// printk("物理内存映射失败\n");
// return -EFAULT;
// }
vir_rcc = ioremap(RCC_MP_AHB4ENSETR, 4); // 4 32字节
if (vir_rcc == NULL)
{
printk("物理内存映射失败\n");
return -EFAULT;
}
printk("物理内存映射成功\n");
// 初始化 PE10 PF10 PE8
*vir_rcc |= (0x3 << 4); // 使能GPIOE，F
*vir_led1_moder &= (~(0x3 << 20));
*vir_led1_moder |= (0x1 << 20);
*vir_led2_moder &= (~(0x3 << 20));
*vir_led2_moder |= (0x1 << 20);
*vir_led1_moder &= (~(0x3 << 16));
*vir_led1_moder |= (0x1 << 16);
*vir_led1_odr &= (~(0x1 << 10)); // 默认灭
*vir_led2_odr &= (~(0x1 << 10));
*vir_led1_odr &= (~(0x1 << 8));
printk("初始化成功\n");
return 0;
}
static void __exit mycdev_exit(void)
{
iounmap(vir_rcc);
iounmap(vir_led1_odr);
iounmap(vir_led1_moder);
iounmap(vir_led2_odr);
iounmap(vir_led2_moder);
// iounmap(vir_led3_odr);
// iounmap(vir_led3_moder);
// 字符设备驱动注销
unregister_chrdev(major, "myled");
}
module_init(mycdev_init);
module_exit(mycdev_exit);
MODULE_LICENSE("GPL");
头文件
#ifndef __MYLED_H__
#define __MYLED_H__
//PE10 PF10 PE8
#define PHY_led1_MODER 0x50006000
#define PHY_led2_MODER 0x50007000
// #define PHY_led3_MODER 0x50006000
#define PHY_led1_ODR 0x50006014
#define PHY_led2_ODR 0x50007014
// #define PHY_led3_ODR 0x50006014
#define RCC_MP_AHB4ENSETR 0x50000A28
// #include "stm32mp1xx_rcc.h"
// #include "stm32mp1xx_gpio.h"ss
#endif
