- remove unused variable TOPDIR
diff --git a/Makefile b/Makefile
index c3b54ad..a88062e 100644
--- a/Makefile
+++ b/Makefile
@@ -12,12 +12,11 @@
 	defconfig allyesconfig allnoconfig clean distclean \
 	release tags
 
-ifndef TOPDIR
-TOPDIR=$(CURDIR)/
-endif
+# the toplevel sourcedir
 ifndef top_srcdir
 top_srcdir=$(CURDIR)
 endif
+# toplevel directory of the object-tree
 ifndef top_builddir
 top_builddir=$(CURDIR)
 endif
@@ -70,7 +69,6 @@
 	$(MAKE) -C $(KBUILD_OUTPUT) \
 	top_srcdir=$(CURDIR) \
 	top_builddir=$(KBUILD_OUTPUT) \
-	TOPDIR=$(KBUILD_OUTPUT) \
 	KBUILD_SRC=$(CURDIR) \
 	-f $(CURDIR)/Makefile $@