问题描述

linux驱动加载后能找到设备，但是/dev下不能找到设备文件

linux驱动加载后能找到设备，但是/dev下不能找到设备文件，我用的是动态分配设备号，insmod也能通过，但是/dev下就是找不到设备文件，加载后也不能通过测试程序我基本上直接用的板子例程，静态动态我都试了，就是不行，日志文件里面也什么都没有，板子是2410的，主机是红帽的，希望大神能够指点迷津
/*
****************************************Copyright (c)**************************************************
** Guangzhou Zhiyuan Electronic Co.LTD.
** graduate school
** http://www.zyinside.com
**
**------------------------------------- File Info ------------------------------------------------------
** File name: magic-leds.c
** Last modified Date: 2005-12-28
** Last Version: 1.0
** Descriptions: Driver for LEDs and BEEP on MagicARM2410.
** Based on Linux 2.4.18.
**------------------------------------------------------------------------------------------------------
** Created by: Chenxibing
** Created date: 2005-12-27
** Version: 1.0
** Descriptions: Preliminary version.
**
**------------------------------------------------------------------------------------------------------
** Modified by:
** Modified date:
** Version:
** Descriptions:
**

---

*/

#ifndef KERNEL
#define KERNEL
#endif

#ifndef MODULE
#define MODULE
#endif

#include
#include
#include
#include
#include
#include
//#include
//#include
//#include
//#include
//#include
#include

#define DEVICE_NAME ""magic-leds""
#define LED_MAJOR 231 //can be 231~239 or 240~254

MODULE_LICENSE(""GPL"");
MODULE_DESCRIPTION(""Guangzhou Zhiyuan Electronic Co.LTD.ngraduate schoolnhttp://www.zyinside.com"");
MODULE_SUPPORTED_DEVICE(""Linux 2.4.18 & MagicARM2410"");
MODULE_AUTHOR(""Chenxibing"");

/*

---

** LEDs' informations.

---

*/
static unsigned long leds_table[] =
{
GPIO_E11
GPIO_E12
GPIO_H4
GPIO_H6
GPIO_H10
};

/*

---

** Function name: magic_leds_ioctl()
** Descriptions : IO control function
** Input:
** inode : information of device
** filp : pointer of file
** cmd : command
** arg : additive parameter
** Output:
** 0 : OK
** other : not OK
** Created by : Chenxibing
** Created Date : 2005-12-27
**-----------------------------------------------------------------------------------------------------
** Modified by :
** Modified Date:
**-----------------------------------------------------------------------------------------------------

---

*/
static int magic_leds_ioctl(struct inode *inode struct file *filp unsigned int cmd unsigned long arg)
{
if (arg > 4) return -EINVAL;

switch(cmd) {    case 0:    case 1:        write_gpio_bit(leds_table[arg] cmd);    default:        return -EINVAL;}

}

/*

---

** Function name: magic_leds_open()
** Descriptions : open leds
** Input:
** inode : information of device
** filp : pointer of file
** Output:
** 0 : OK
** other : not OK
** Created by : Chenxibing
** Created Date : 2005-12-27
**-----------------------------------------------------------------------------------------------------
** Modified by :
** Modified Date:
**-----------------------------------------------------------------------------------------------------

---

*/
static int magic_leds_open(struct inode *inode struct file *filp)
{
int i;

for (i = 0; i < 5; i++){    set_gpio_ctrl(leds_table[i] | GPIO_PULLUP_EN | GPIO_MODE_OUT);    write_gpio_bit(leds_table[i] 1);}MOD_INC_USE_COUNT;printk(KERN_INFO DEVICE_NAME "": opened.n"");return 0;

}

/*

---

** Function name: magic_leds_release()
** Descriptions : release leds
** Input:
** inode : information of device
** filp : pointer of file
** Output:
** 0 : OK
** other : not OK
** Created by : Chenxibing
** Created Date : 2005-12-27
**-----------------------------------------------------------------------------------------------------
** Modified by :
** Modified Date:
**-----------------------------------------------------------------------------------------------------

---

*/
static int magic_leds_release(struct inode *inode struct file *filp)
{
MOD_DEC_USE_COUNT;
printk(KERN_INFO DEVICE_NAME "": released.n"");
return 0;
}

/*

---

** operations of the driver

---

*/
static struct file_operations magic_leds_fops =
{
owner: THIS_MODULE
ioctl: magic_leds_ioctl
open: magic_leds_open
release: magic_leds_release
};

/*

---

** Function name: magic_leds_init()
** Descriptions : register driver
** Input:
** : NONE
** Output:
** 0 : OK
** other : not OK
** Created by : Chenxibing
** Created Date : 2005-12-27
**-----------------------------------------------------------------------------------------------------
** Modified by :
** Modified Date:
**-----------------------------------------------------------------------------------------------------

---

*/
static devfs_handle_t devfs_handle;
static int __init magic_leds_init(void)
{
int result;
printk(""""""leds devn"");

result = register_chrdev(LED_MAJOR DEVICE_NAME &magic_leds_fops);
if (result < 0)
{
printk(KERN_ERR DEVICE_NAME "": Failed to register major.n"");
return result;
}
// devfs_handle = devfs_register(NULL DEVICE_NAME DEVFS_FL_AUTO_DEVNUM
// 0 0 S_IFCHR | S_IRUSR | S_IWUSR &magic_leds_fops NULL);

// printk(KERN_INFO DEVICE_NAME "": Initialize OK.n"");
// return 0;
}

/*

---

** Function name: magic_leds_exit()
** Descriptions : unregister driver
** Input:
** : NONE
** Output:
** 0 : OK
** other : not OK
** Created by : Chenxibing
** Created Date : 2005-12-27
**-----------------------------------------------------------------------------------------------------
** Modified by :
** Modified Date:
**-----------------------------------------------------------------------------------------------------

---

*/

static void __exit magic_leds_exit(void)
{
// devfs_unregister(devfs_handle);
unregister_chrdev(LED_MAJOR DEVICE_NAME);
}

module_init(magic_leds_init);
module_exit(magic_leds_exit);
/*

---

** End of File

---

*/

解决方案

注册完设备文件可以在/proc/devices下看到设备名，还要建立设备节点...在/dev下看到的就是