diff --git a/src/mux_pt.c b/src/mux_pt.c
index 479f831..cd3a28b 100644
--- a/src/mux_pt.c
+++ b/src/mux_pt.c
@@ -51,8 +51,9 @@
 
 	ret = cs->data_cb->wake ? cs->data_cb->wake(cs) : 0;
 
-	cs_update_mux_polling(cs);
-	return (ret);
+	if (ret >= 0)
+		cs_update_mux_polling(cs);
+	return ret;
 }
 
 /* callback used to update the mux's polling flags after changing a cs' status.