diff --git a/tools/iio/iio_utils.c b/tools/iio/iio_utils.c
index 31aca9ab078bf8d42444f75cdc9c3b4b721ccadb..4bbd6e7959cdad471e6cb0bdbf0d0cda915cd743 100644
--- a/tools/iio/iio_utils.c
+++ b/tools/iio/iio_utils.c
@@ -537,7 +537,7 @@ int build_channel_array(const char *device_dir,
 	return ret;
 }
 
-int calc_digits(int num)
+static int calc_digits(int num)
 {
 	int count = 0;