diff --git a/tests/path_offset.c b/tests/path_offset.c
index 82527d4..8e657af 100644
--- a/tests/path_offset.c
+++ b/tests/path_offset.c
@@ -41,7 +41,7 @@ static int check_subnode(void *fdt, int parent, const char *name)
 	return offset;
 }
 
-static void check_path_offset(void *fdt, char *path, int offset)
+static void check_path_offset(void *fdt, const char *path, int offset)
 {
 	int rc;
 
@@ -56,7 +56,7 @@ static void check_path_offset(void *fdt, char *path, int offset)
 		     " %d instead of %d", path, rc, offset);
 }
 
-static void check_path_offset_namelen(void *fdt, char *path, int namelen,
+static void check_path_offset_namelen(void *fdt, const char *path, int namelen,
 				      int offset)
 {
 	int rc;
diff --git a/tests/utilfdt_test.c b/tests/utilfdt_test.c
index ba6462f..f62341c 100644
--- a/tests/utilfdt_test.c
+++ b/tests/utilfdt_test.c
@@ -50,7 +50,7 @@ static void checkfail(const char *fmt)
  * \param expected_size	The size (in bytes) that we expect (ignored for
  *			strings)
  */
-static void check_sizes(char *modifier, int expected_size)
+static void check_sizes(const char *modifier, int expected_size)
 {
 	char fmt[10], *ptr;