喜羊羊系列之【初级驱动--模块通信】

#include<linux/init.h>
#include<linux/module.h>

int add(int i,int j){
    return i+j;
}
int sub(int i,int j){
    return i-j;
}

EXPORT_SYMBOL(add);
EXPORT_SYMBOL(sub);

MODULE_LICENSE("GPL");

#include<linux/init.h>
#include<linux/module.h>
#include "head.h"

int a=5;
int b=3;
module_param(a,int,S_IRWXU);
module_param(b,int,S_IRWXU); 

static int  __init hello_init(){
    printk(KERN_INFO"hello is module!\n");
	printk(KERN_INFO"a  = %d\n",a);
	printk(KERN_INFO"b  = %d\n",b);
	printk(KERN_INFO"a + b = %d\n",add(a,b));
	printk(KERN_INFO"a  = %d\n",a);
	printk(KERN_INFO"b  = %d\n",b);
	printk(KERN_INFO"a - b = %d\n",sub(a,b));

    return 0;
}

static void __exit hello_exit(){
    printk(KERN_INFO"hello is unmod!\n");
}

module_init(hello_init);
module_exit(hello_exit);
MODULE_LICENSE("GPL");

#ifndef _HEAD_H
#define _HEAD_H

extern int add(int ,int );
extern int sub(int ,int );
#endif

ifeq ($(KERNELRELEASE),)
	KERNELDIR =/home/farsight/work/kernel/linux-3.0.8
	PWD =$(shell pwd)
modules:
	$(MAKE) -C $(KERNELDIR) M=$(PWD) modules
	cp add_sub.ko /opt/filesystem/s5pv210
modules_install:
	$(MAKE) -C $(KERNELDIR) M=$(PWD) modules_install
clean:
	rm -rf *.so *.o *.ko  .tmp_versions *.mod.c *.order *.symvers
else
	obj-m :=add_sub.o
endi