range Pi User Manual Copyright reserved by Shenzhen Xunlong Software Co., Ltd
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4) Then you can write a hello kernel module to test the kernel header file
a. First write the code of the hello kernel module, as follows:
orangepi@orangepi:~$ vim hello.c
#include <linux/init.h>
#include <linux/module.h>
static int hello_init(void)
{
printk("Hello Orange Pi -- init\n");
return 0;
}
static void hello_exit(void)
{
printk("Hello Orange Pi -- exit\n");
return;
}
module_init(hello_init);
module_exit(hello_exit);
MODULE_LICENSE("GPL");
b. Then write the Makefile for compiling the hello kernel module, as follows:
orangepi@orangepi:~$ vim Makefile
ifneq ($(KERNELRELEASE),)
obj-m:=hello.o
else
KDIR :=/lib/modules/$(shell uname -r)/build
PWD :=$(shell pwd)
all:
make -C $(KDIR) M=$(PWD) modules
clean:
rm -f *.ko *.o *.mod.o *.mod *.symvers *.cmd *.mod.c *.order