linux驱动编译(多目录多源文件)

$ tree .
|-- Makefile
|-- a.c
|-- m
|   |-- b.h
|   `-- b.c

//a.c
#include <linux/init.h>
#include <linux/module.h>
 
#include "b.h"
 
MODULE_LICENSE("GPL");
 
static __init int a(void)
{
    led_on();
 
    return 0;
}
 
static __exit void b(void)
{
    led_off();
}
 
module_init(a);
module_exit(b);

//b.h
 
#ifndef _B_H_
#define _B_H_
 
void led_on(void);
void led_off(void);
 
#endif // _B_H_

//b.c
#include <linux/module.h>
 
#include "b.h"
 
void led_on(void)
{
    printk("%s %d LED ON\n", __func__, __LINE__);
}
 
void led_off(void)
{
    printk("%s %d LED OFF\n", __func__, __LINE__);
}

#Makefile
PWD=$(shell pwd)
TARGET := test
obj-m = $(TARGET).o
$(TARGET)-objs = a.o  ./m/b.o

#KERN = /share/arm/linux-3.2
KERN = /lib/modules/`uname -r`/build/

EXTRA_CFLAGS += -I$(INCDIR) #关键
 
all:
	make -C $(KERN) M=`pwd` $(CFLAGS) INCDIR=$(PWD)/m modules
 
clean:
	make -C $(KERN) M=`pwd` INCDIR=$(PWD)/m modules clean
#        rm -rf modules.order
#no more