驱动开发作业2 —— ioctl

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已于 2023-07-05 17:17:34 修改 · 683 阅读

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#驱动开发

于 2023-07-05 17:12:09 首次发布

该代码示例展示了如何编写Linux驱动程序，通过ioctl系统调用接口来控制GPIO，实现对LED、蜂鸣器、风扇和马达的开关操作。每个设备都有相应的驱动文件，如led.c、beep.c、fan.c和motor.c，它们包含了设备初始化、ioctl处理等功能。在用户空间，test.c文件用于测试这些驱动，通过读写和ioctl调用来控制硬件。

通过ioctl函数选择不同硬件的控制，如实现对LED、蜂鸣器、马达、风扇的控制

1.将GPIO的相关寄存器封装成结构体 --------> gpio.h

2.LED相关驱动文件 --------> led.c

3.蜂鸣器相关驱动文件 --------> beep.c

4.风扇相关驱动文件 --------> fan.c

5.马达相关驱动文件 --------> motor.c

6.应用层测试文件 --------> test.c

gpio.h

/*
 * Copyright (c) 2023 by Huijie Xia, All Rights Reserved.
 * @Author: Huijie Xia
 * @Date: 2023-07-05 16:21:43
 * @LastEditTime: 2023-07-05 16:47:21
 * @FilePath: /B_Drive/day3/led_beep_fan_motor/gpio.h
 * @version:
 * @Description:
 */
#ifndef __GPIO_H_
#define __GPIO_H_

typedef struct {
    volatile unsigned int MODER; // 0x00
    volatile unsigned int OTYPER; // 0x04
    volatile unsigned int OSPEEDR; // 0x08
    volatile unsigned int PUPDR; // 0x0C
    volatile unsigned int IDR; // 0x10
    volatile unsigned int ODR; // 0x14
    volatile unsigned int BSRR; // 0x18
    volatile unsigned int LCKR; // 0x1C
    volatile unsigned int AFRL; // 0x20
    volatile unsigned int AFRH; // 0x24
    volatile unsigned int BRR; // 0x28
    volatile unsigned int res;
    volatile unsigned int SECCFGR; // 0x30
} gpio_t;

#define PHY_RCC_GPIO 0x50000A28
#define PHY_GPIOB_BASE 0x50003000
#define PHY_GPIOE_BASE 0x50006000
#define PHY_GPIOF_BASE 0x50007000

#define LED1_ON _IO('l', 1)
#define LED1_OFF _IO('l', 0)
#define LED_ON _IOW('l', 1, int)
#define LED_OFF _IOW('l', 0, int)

#define FAN_ON _IO('f', 1)
#define FAN_OFF _IO('f', 0)

#define BEEP_ON _IO('b', 1)
#define BEEP_OFF _IO('b', 0)

#define MOTOR_ON _IO('m', 1)
#define MOTOR_OFF _IO('m', 0)

#endif

led.c

/*
 * Copyright (c) 2023 by Huijie Xia, All Rights Reserved.
 * @Author: Huijie Xia
 * @Date: 2023-06-29 08:56:26
 * @LastEditTime: 2023-07-05 16:24:06
 * @FilePath: /B_Drive/day3/led_beep_fan_motor/led.c
 * @version:
 * @Description: 驱动控制LED灯
 */
#include "gpio.h"
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/uaccess.h>

#define CNAME "myled"
struct class* cls;
struct device* dev;

int major;
char kbuf[128] = { 0 };
unsigned int* KERNEL_RCC_GPIO;
gpio_t* KERNEL_GPIOE_BASE;
gpio_t* KERNEL_GPIOF_BASE;

int mycdev_open(struct inode* inode, struct file* file)
{
    printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);
    /* 地址映射 */
    KERNEL_RCC_GPIO = ioremap(PHY_RCC_GPIO, 4);
    if (KERNEL_RCC_GPIO == NULL) {
        printk("ioremap RCC error!\n");
        return -ENOMEM;
    }
    KERNEL_GPIOE_BASE = ioremap(PHY_GPIOE_BASE, sizeof(gpio_t));
    if (KERNEL_GPIOE_BASE == NULL) {
        printk("ioremap GPIOE BASE error!\n");
        return -ENOMEM;
    }
    KERNEL_GPIOF_BASE = ioremap(PHY_GPIOF_BASE, sizeof(gpio_t));
    if (KERNEL_GPIOF_BASE == NULL) {
        printk("ioremap GPIOF BASE error!\n");
        return -ENOMEM;
    }

    /* LED1(PE10)寄存器初始化(读,改,写) */
    writel(readl(KERNEL_RCC_GPIO) | (0x1 << 4), KERNEL_RCC_GPIO); /* GPIOE时钟使能 */
    writel(readl(&KERNEL_GPIOE_BASE->MODER) & (~(0x3 << 20)), &KERNEL_GPIOE_BASE->MODER); /* MODER寄存器21~20bit清零 */
    writel(readl(&KERNEL_GPIOE_BASE->MODER) | (0x1 << 20), &KERNEL_GPIOE_BASE->MODER); /* MODER寄存器设置为输出模式 */
    writel(readl(&KERNEL_GPIOE_BASE->ODR) & (~(0x1 << 10)), &KERNEL_GPIOE_BASE->ODR); /* LED1熄灭 */

    /* LED2(PF10)寄存器初始化(读,改,写) */
    writel(readl(KERNEL_RCC_GPIO) | (0x1 << 5), KERNEL_RCC_GPIO); /* GPIOF时钟使能 */
    writel(readl(&KERNEL_GPIOF_BASE->MODER) & (~(0x3 << 20)), &KERNEL_GPIOF_BASE->MODER); /* MODER寄存器21~20bit清零 */
    writel(readl(&KERNEL_GPIOF_BASE->MODER) | (0x1 << 20), &KERNEL_GPIOF_BASE->MODER); /* MODER寄存器设置为输出模式 */
    writel(readl(&KERNEL_GPIOF_BASE->ODR) & (~(0x1 << 10)), &KERNEL_GPIOF_BASE->ODR); /* LED2熄灭 */

    /* LED3(PE8)寄存器初始化(读,改,写) */
    writel(readl(KERNEL_RCC_GPIO) | (0x1 << 4), KERNEL_RCC_GPIO); /* GPIOE时钟使能 */
    writel(readl(&KERNEL_GPIOE_BASE->MODER) & (~(0x3 << 16)), &KERNEL_GPIOE_BASE->MODER); /* MODER寄存器21~20bit清零 */
    writel(readl(&KERNEL_GPIOE_BASE->MODER) | (0x1 << 16), &KERNEL_GPIOE_BASE->MODER); /* MODER寄存器设置为输出模式 */
    writel(readl(&KERNEL_GPIOE_BASE->ODR) & (~(0x1 << 8)), &KERNEL_GPIOE_BASE->ODR); /* LED3熄灭 */

    return 0;
}

ssize_t mycdev_read(struct file* file, char __user* ubuf,
    size_t size, loff_t* offs)
{
    int ret;
    printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);
    if (size > sizeof(kbuf)) {
        size = sizeof(kbuf);
    }
    ret = copy_to_user(ubuf, kbuf, size);
    if (ret) {
        printk("copy data to user error!\n");
        return -EIO;
    }
    return size;
}
ssize_t mycdev_write(struct file* file, const char __user* ubuf,
    size_t size, loff_t* offs)
{
    int ret;
    printk("%s:%s:%d\n", __FILE__, __func__, __LINE__);
    if (size > sizeof(kbuf)) {
        size = sizeof(kbuf);
    }
    ret = copy_from_user(kbuf, ubuf, size);

    if (ret) {
        printk("copy data from user error!\n");
        return -EIO;
    }

    // switch (kbuf[0]) {