Question

我正在尝试创建一个简单的内核模块，使键盘LED闪烁。它在Linux 3.16（Ubuntu 14.04）上运行良好，但它不会改变4.5（Arch）上的LED状态。

我无法弄清楚它会带来什么样的差异，我在demsg中找不到任何有用的东西。知道我怎么能找到这个问题？

代码：

#include <linux/module.h>
#include <linux/device.h>
#include <linux/tty.h>
#include <linux/kd.h>
#include <linux/vt.h>
#include <linux/console_struct.h>
#include <linux/vt_kern.h>
#include "device.h"
#include "timer.h"

#define LEDS_ON 0x07
#define LEDS_OFF 0xFF

static int major_number;
static struct class *class;
static struct tty_driver *driver; 
static unsigned long led_status = LEDS_OFF;


static void timer_callbak(void)
{
    if (led_status == LEDS_OFF) {
        led_status = LEDS_ON;
    } else {
        led_status = LEDS_OFF;
    }

    driver->ops->ioctl(vc_cons[fg_console].d->port.tty, KDSETLED, led_status);
}

static long device_ioctl(struct file *file, unsigned int command, unsigned long argument)
{
    if (command == ON && led_status == LEDS_OFF) {
        timer_init(&timer_callbak);
    } else if (command == OFF && led_status == LEDS_OFF){
        timer_exit();
    } else if (command != OFF && command != ON) {
        printk(KERN_WARNING "Invalid ioctl() command");

        return -1;
    } 

    return 0;
}

static struct file_operations operations = {
        .unlocked_ioctl = device_ioctl
};

dev_t create_dev_type(void) 
{
    return MKDEV(major_number, 0);
}

void create_device(void)
{
    major_number = register_chrdev(0, NAME, &operations);
    printk("Keyboard leds registered with major_number \"%d\"", major_number);

    class = class_create(THIS_MODULE, NAME);
    device_create(class, NULL, create_dev_type(), NULL, NAME);
}

void device_init(void) 
{
    create_device();
    driver = vc_cons[fg_console].d->port.tty->driver;

    printk("Keyboard leds device Initialized");
}

void device_exit(void)
{
    device_destroy(class,  create_dev_type());
    class_unregister(class);
    class_destroy(class);
    unregister_chrdev(major_number, NAME);

    printk("Keyboard leds device exited");
}

MODULE_LICENSE("GPL");

这就是我试图调用它的方式：

#include <sys/ioctl.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include "src/device.h"


int main(void)
{
    int fd;

    if ((fd = open("/dev/keyboard_leds", O_RDWR|O_NONBLOCK)) < 0) {
        perror("Open failed!");

        return -1;
    }

    ioctl(fd, ON);
    close(fd);

    return 0;
}

Linux内核版本不匹配

0 个答案: