diff --git a/tools/gpio/Makefile b/tools/gpio/Makefile
index 342e056c8c66..1cd7636b9cac 100644
--- a/tools/gpio/Makefile
+++ b/tools/gpio/Makefile
@@ -7,7 +7,13 @@ bindir ?= /usr/bin
 # isn't set and when invoked from selftests build, where srctree
 # is set to ".". building_out_of_srctree is undefined for in srctree
 # builds
+ifeq ($(srctree),)
+update_srctree := 1
+endif
 ifndef building_out_of_srctree
+update_srctree := 1
+endif
+ifeq ($(update_srctree),1)
 srctree := $(patsubst %/,%,$(dir $(CURDIR)))
 srctree := $(patsubst %/,%,$(dir $(srctree)))
 endif