diff --git a/script.c b/script.c
index a2d9029..015e817 100644
--- a/script.c
+++ b/script.c
@@ -207,7 +207,7 @@ struct script_string_entry *script_string_entry_new(struct script_section *secti
 struct script_gpio_entry *script_gpio_entry_new(struct script_section *section,
 						const char *name,
 						unsigned port, unsigned num,
-						unsigned data[4])
+						int32_t data[4])
 {
 	struct script_gpio_entry *entry;
 
diff --git a/script.h b/script.h
index 193d495..9ce60a9 100644
--- a/script.h
+++ b/script.h
@@ -72,7 +72,7 @@ struct script_gpio_entry {
 	struct script_entry entry;
 
 	unsigned port, port_num;
-	unsigned data[4];
+	int32_t data[4];
 };
 
 /** create a new script tree */
@@ -104,6 +104,6 @@ struct script_string_entry *script_string_entry_new(struct script_section *secti
 struct script_gpio_entry *script_gpio_entry_new(struct script_section *script,
 						const char *name,
 						unsigned port, unsigned num,
-						unsigned data[4]);
+						int32_t data[4]);
 
 #endif