/*?
?*??devDrv.c?
?*??threeProcess?
?*??Created?on:?2012-2-24?
?*??????Author:?zhushengben?
?*/??
??
#include?“linux/kernel.h“??
#include?“linux/module.h“??
#include?“linux/fs.h“??
#include?“linux/init.h“??
#include?“linux/types.h“??
#include?“linux/errno.h“??
#include?“linux/uaccess.h“??
#include?“linux/kdev_t.h“??
#define?MAX_SIZE?1024??
??
static?int?my_open（struct?inode?*inode?struct?file?*file）;??
static?int?my_release（struct?inode?*inode?struct?file?*file）;??
static?ssize_t?my_read（struct?file?*file?char?__user?*user?size_t?t?loff_t?*f）;??
static?ssize_t?my_write（struct?file?*file?const?char?__user?*user?size_t?t?loff_t?*f）;??
??
static?char?message[MAX_SIZE]?=?“-------congratulations--------!“;??
static?int?device_num?=?0;//設備號??
static?int?counter?=?0;//計數用??
static?int?mutex?=?0;//互斥用??
static?char*?devName?=?“myDevice“;//設備名??
??
struct?file_operations?pStruct?=??
{?open:my_open?release:my_release?read:my_read?write:my_write?};??
??
/*?注冊模塊?*/??
int?init_module（）??
{??
????int?ret;??
????/*?函數中第一個參數是告訴系統，新注冊的設備的主設備號由系統分配，?
?????*?第二個參數是新設備注冊時的設備名字，?
?????*?第三個參數是指向file_operations的指針，?
?????*?當用設備號為0創建時，系統一個可以用的設備號創建模塊?*/??
????ret?=?register_chrdev（0?devName?&pStruct）;??
????if?（ret?????{??
????????printk（“regist?failure!\n“）;??
????????return?-1;??
????}??
????else??
????{??
????????printk（“the?device?has?been?registered!\n“）;??
????????device_num?=?ret;??
????????printk（“<1>the?virtual?device‘s?major?number?%d.\n“?device_num）;??
????????printk（“<1>Or?you?can?see?it?by?using\n“）;??
????????printk（“<1>------more?/proc/devices-------\n“）;??
????????printk（“<1>To?talk?to?the?drivercreate?a?dev?file?with\n“）;??
????????printk（“<1>------‘mknod?/dev/myDevice?c?%d?0‘-------\n“?device_num）;??
????????printk（“<1>Use?\“rmmode\“?to?remove?the?module\n“）;??
??
????????return?0;??
????}??
}??
/*?注銷模塊，函數名很特殊?*/??
void?cleanup_module（）??
{??
????unregister_chrdev（device_num?devName）;??
????printk（“unregister?it?success!\n“）;??
}??
??
static?int?my_open（struct?inode?*inode?struct?file?*file）??
{??
????if?（mutex）??
????????return?-EBUSY;??
????mutex?=?1;//上鎖??
????printk（“<1>main??device?:?%d\n“?MAJOR（inode->i_rdev））;??
????printk（“<1>slave?device?:?%d\n“?MINOR（inode->i_rdev））;??
????printk（“<1>%d?times?to?call?the?device\n“?++counter）;??
????try_module_get（THIS_MODULE）;??
????return?0;??
}??
/*?每次使用完后會release?*/??
static?int?my_release（struct?inode?*inode?struct?file?*file）??
{??
????printk（“Device?released!\n“）;??
????module_put（THIS_MODULE）;??
????mutex?=?0;//開鎖??
????return?0;??
}??
??
static?ssize_t?my_read（struct?file?*file?char?__user?*user?size_t?t?loff_t?*f）??
{??
????if（copy_to_user（usermessagesizeof（message）））??
????{??
????????return?-EFAULT;??
????}??
????return?sizeof（message）;??
}??
??
static?ssize_t?my_write（struct?file?*file?const?char?__user?*user?size_t?t?loff_t?*f）??
{??
????if（copy_from_user（message

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

?????文件???????3230??2017-05-09?19:42??Linux增加字符設備驅動實驗\devDrv.c

?????文件????????803??2017-05-09?19:43??Linux增加字符設備驅動實驗\Makefile

?????文件???????1211??2017-05-09?19:44??Linux增加字符設備驅動實驗\test.c

?????目錄??????????0??2017-05-09?19:44??Linux增加字符設備驅動實驗

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

?????????????????5244????????????????????4