#To test for an empty value
ifeq ($(KERNELRELEASE),)
    KERNELDIR = /lib/modules/$(shell uname -r)/build
    PWD = $(shell pwd)

modules:
	$(MAKE) -C $(KERNELDIR) M=$(PWD) modules

clean:
	rm -rf *.o *~ core .*.cmd *.ko *.mod.c .tmp_* Module.symvers

.PHONY: modules modules_install clean

else
    obj-m = hello.o 
endif
