diff --git a/tools/checkpatch.sh b/tools/checkpatch.sh
index 33b6dfc17..e1dd267f9 100755
--- a/tools/checkpatch.sh
+++ b/tools/checkpatch.sh
@@ -1,4 +1,5 @@
 #!/bin/sh
 #
 
-git format-patch -M --stdout HEAD^ | tools/scripts/checkpatch.pl - --no-tree
+since=${1:-HEAD^}
+git format-patch -M --stdout $since | tools/scripts/checkpatch.pl - --no-tree