Linux驱动编程--基于I2C子系统的I2C驱动的Makefile

ifeq ($(KERNELRELEASE),)
KERNELDIR ?= /lib/modules/$(shell uname -r)/build
PWD := $(shell pwd)
TEST = test
modules:
    $(MAKE) -C $(KERNELDIR) M=$(PWD)
clean:
    rm -rvf *.ko *.o *.mod.c Module* module*
test:
    gcc $(TEST).c -o $(TEST)
mknod:
    sudo mknod /dev/my_hello c 365 0
insmod:
    sudo insmod my_hello.ko
.PHONY:modules clean mknod test insmod
else
obj-m := hello.o
endif