diff --git a/src/libnm-core-impl/nm-setting-wired.c b/src/libnm-core-impl/nm-setting-wired.c
index f17fa6b7bd..5a0e004cdd 100644
--- a/src/libnm-core-impl/nm-setting-wired.c
+++ b/src/libnm-core-impl/nm-setting-wired.c
@@ -464,9 +464,9 @@ nm_setting_wired_get_num_s390_options(NMSettingWired *setting)
  * @setting: the #NMSettingWired
  * @idx: index of the desired option, from 0 to
  * nm_setting_wired_get_num_s390_options() - 1
- * @out_key: (out) (transfer none): on return, the key name of the s390 specific
+ * @out_key: (allow-none) (out) (transfer none): on return, the key name of the s390 specific
  *   option; this value is owned by the setting and should not be modified
- * @out_value: (out) (transfer none): on return, the value of the key of the
+ * @out_value: (allow-none) (out) (transfer none): on return, the value of the key of the
  *   s390 specific option; this value is owned by the setting and should not be
  *   modified
  *