diff --git a/drivers/aic8800/aic_btusb/Makefile b/drivers/aic8800/aic_btusb/Makefile
index 2ee1dcc..41d3718 100644
--- a/drivers/aic8800/aic_btusb/Makefile
+++ b/drivers/aic8800/aic_btusb/Makefile
@@ -55,7 +55,7 @@ ifeq ($(CONFIG_PLATFORM_UBUNTU), y)
 ccflags-$(CONFIG_PLATFORM_UBUNTU) += -DCONFIG_PLATFORM_UBUNTU
 
 KVER ?= $(shell uname -r)
-KDIR  = /lib/modules/$(KVER)/build
+KDIR ?= /lib/modules/$(KVER)/build
 PWD   := $(shell pwd)
 MODDESTDIR := /lib/modules/$(KVER)/kernel/drivers/net/wireless/aic8800
 SUBARCH = $(shell uname -m | sed -e s/i.86/i386/ -e s/armv.l/arm/ -e s/aarch64/arm64/)