diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index c1fa20a4e342..4b4358930470 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -2509,10 +2509,8 @@ static void gsm_cleanup_mux(struct gsm_mux *gsm, bool disc)
 		gsm->has_devices = false;
 	}
 	for (i = NUM_DLCI - 1; i >= 0; i--)
-		if (gsm->dlci[i]) {
+		if (gsm->dlci[i])
 			gsm_dlci_release(gsm->dlci[i]);
-			gsm->dlci[i] = NULL;
-		}
 	mutex_unlock(&gsm->mutex);
 	/* Now wipe the queues */
 	tty_ldisc_flush(gsm->tty);