//模塊定義
#include?
#include?
#include?
#include?
#include?
#include?
#include?
MODULE_LICENSE（“GPL“）;

static?int?chdr_major?=?150;//主設備號
static?int?chdr_minor?=?0;//次設備號
static?int?chdr_nr_devs?=?1;
static?int?open_nr=0;//打開設備的進程數
static?struct?cdev?*chdr_cdev;//設備定義聲明
static?char?buffer[100];//緩沖區


//函數聲明
static?int?chdr_open（struct?inode?*inode?struct?file?*filp）;
static?int?chdr_release（struct?inode?*inode?struct?file*?filp）;
static?ssize_t?chdr_read（struct?file?*file?char?__user?*buf?size_t?count?loff_t?*f_pos）;
static?ssize_t?chdr_write（struct?file?*file?const?char?__user?*buf?size_t?count?loff_t?*f_pos）;

//設備模塊接口
static?struct?file_operations?chdr_fops?=?{
????.owner???=?THIS_MODULE
????.read????=?chdr_read
????.write???=?chdr_write
????.open????=?chdr_open
????.release?=?chdr_release
};???


//打開函數
static?int?chdr_open（struct?inode?*inode?struct?file?*filp）
{
????if?（open_nr?==?0）?{

????????open_nr++;
????}?else?{
????????printk（KERN_ALERT?“Another?process?open?the?char?device.\n“）;//進程掛起
????????return?-1;
????}

????return?0;
}

//閱讀函數
static?ssize_t?chdr_read（struct?file?*file?char?__user?*buf?size_t?count?loff_t?*f_pos）
{
????if?（buf?==?NULL）
????????return?0;
????if?（count?>?100）
????????count?=?100;

????copy_to_user（buf?buffer?count）;//讀緩沖
????return?count;
}

//寫入函數
static?ssize_t?chdr_write（struct?file?*file?const?char?__user?*buf?size_t?count?loff_t?*f_pos）
{
????if?（buf?==?NULL）
????????return?0;
????if?（count?>?100）
????????count?=?100;

????copy_from_user（buffer?buf?count）;//寫緩沖
????return?count;
}

//釋放設備函數
static?int?chdr_release（struct?inode?*inode?struct?file*?filp）
{
????open_nr--;//進程數減1
????return?0;
}

//注冊設備函數
static?int?__init?chdr_init（void）
{
????int?result?err;
????dev_t?dev?=?0;

????printk（KERN_ALERT?“Begin?to?init?Char?Device!\n%d“open_nr）;
//注冊設備
????if?（chdr_major）?{
????????dev?=?MKDEV（chdr_major?chdr_minor）;
????????result?=?register_chrdev_region（dev?chdr_nr_devs?“chdr“）;
????}?else?{
????????result?=?alloc_chrdev_region（&dev?chdr_minor?chdr_nr_devs?“chdr“）;
????????chdr_major?=?MAJOR（dev）;
????}

????if?（result?????????printk（KERN_WARNING?“chdr:?cannot?get?major?%d\n“?chdr_major）;
????????return?result;
????}???
???
????chdr_cdev?=?cdev_alloc（）;
????if?（chdr_cdev?==?NULL）?{
????????printk（KERN_WARNING?“chdr:?alloc?cdev?failed.\n“）;

????????return?-1;
????}

//初始化設備
????chdr_cdev->owner?=?THIS_MODULE;
????chdr_cdev->ops?=?&chdr_fops;
????cdev_init（chdr_cdev?&chdr_fops）;
????err?=?cdev_add（chdr_cdev?dev?1）;
????if?（err）?{
????????printk（KERN_NOTICE?“Error?%d?adding?chdr.\n“?err）;
????}

????open_nr?=?0;
printk（“%d“open_nr）;
????return?0;
}


//注銷設備函數
static?void?__exit?chdr_exit（void）
{
????dev_t?dev;

????printk（KERN_ALERT?“Unloading...\n“）;
????dev?=?MKDEV（chdr_major?chdr_minor）;
????unregister_chrdev_region（dev?chdr_nr_devs）;//注銷設備
????cdev_del（chdr_cd

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件????????206??2009-06-03?13:21??驅動設計\Makefile

?????文件???????3294??2009-06-03?13:31??驅動設計\mydrive.c

?????文件????????875??2009-06-03?13:32??驅動設計\test.c

?????文件??????24251??2009-06-15?23:34??驅動設計\設備驅動實習報告.docx

?????目錄??????????0??2009-06-15?23:35??驅動設計

-----------?---------??----------?-----??----

????????????????28626????????????????????5