diff --git a/scripts/qapi/gen.py b/scripts/qapi/gen.py
index 6b1007a035..8b851c6262 100644
--- a/scripts/qapi/gen.py
+++ b/scripts/qapi/gen.py
@@ -257,7 +257,7 @@ class QAPISchemaModularCVisitor(QAPISchemaVisitor):
     def _is_builtin_module(name: Optional[str]) -> bool:
         return not name
 
-    def _module_dirname(self, what: str, name: Optional[str]) -> str:
+    def _module_dirname(self, name: Optional[str]) -> str:
         if self._is_user_module(name):
             return os.path.dirname(name)
         return ''
@@ -275,7 +275,7 @@ class QAPISchemaModularCVisitor(QAPISchemaVisitor):
         return ret
 
     def _module_filename(self, what: str, name: Optional[str]) -> str:
-        return os.path.join(self._module_dirname(what, name),
+        return os.path.join(self._module_dirname(name),
                             self._module_basename(what, name))
 
     def _add_module(self, name: Optional[str], blurb: str) -> None: