編寫helloword驅動，直接上程式碼

Makefile

ifeq ($(KERNELRELEASE),)
    KERNELDIR := /home/carl/work/raspi/linux-rpi-4.9.y
    PWD := $(shell pwd)
modules:
    $(MAKE) -C $(KERNELDIR) M=$(PWD) modules ARCH=arm CROSS_COMPILE=/home/carl/work/raspi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/bin/arm-linux-gnueabihf
 
-
modules_install:
    $(MAKE) -C $(KERNELDIR) M=$(PWD) modules_install ARCH=arm CROSS_COMPILE=/home/carl/work/raspi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/bin/arm-linux-gnueabihf-
clean:
    rm -rf *.o *~core.depend .*.cmd *.mod.c *.tmp_version *.order *.symvers
else
    obj-m := hello.
 
o
endif

hello.c

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

//初始化函式  
static int __init hello_init(void)  
{  
    printk(KERN_ALERT"Hello carl!\n");  
    return 0;  
}  

//退出函式  
static void __exit hello_exit(void)  
{  
    printk(KERN_ALERT"Goodbye carl,nice to see you.\n");  
}  

//對模組函式進行繫結  
 

module_init(hello_init);  
module_exit(hello_exit);  

//許可協議及作者資訊、可以不設定  
MODULE_LICENSE("Dual BSD/GPL");  
MODULE_AUTHOR("Carl.yang");  

編譯完成後會生成hello.ko檔案
將此檔案拷貝到樹莓派
安裝：sudo insmod hello.ko
解除安裝：sudo rmmod hello
檢視核心列印資訊：dmesg