diff --git a/tools/power/acpi/os_specific/service_layers/oslinuxtbl.c b/tools/power/acpi/os_specific/service_layers/oslinuxtbl.c
index 92f1fd700344521a40020ce5ea1ee2908bdf0fe6..db15c9d2049e08f6090d3d391a7617246aa9c1c5 100644
--- a/tools/power/acpi/os_specific/service_layers/oslinuxtbl.c
+++ b/tools/power/acpi/os_specific/service_layers/oslinuxtbl.c
@@ -1156,7 +1156,7 @@ osl_table_name_from_file(char *filename, char *signature, u32 *instance)
 	/* Extract instance number */
 
 	if (isdigit((int)filename[ACPI_NAME_SIZE])) {
-		sscanf(&filename[ACPI_NAME_SIZE], "%d", instance);
+		sscanf(&filename[ACPI_NAME_SIZE], "%u", instance);
 	} else if (strlen(filename) != ACPI_NAME_SIZE) {
 		return (AE_BAD_SIGNATURE);
 	} else {