diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 6c97953d593b..9b152ead050f 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -827,6 +827,9 @@ static void sc16is7xx_tx_proc(struct kthread_work *ws)
 		msleep(port->rs485.delay_rts_before_send);
 
 	guard(mutex)(&one->lock);
+	sc16is7xx_port_update(port, SC16IS7XX_IER_REG,
+			      SC16IS7XX_IER_THRI_BIT,
+			      SC16IS7XX_IER_THRI_BIT);
 	sc16is7xx_handle_tx(port);
 }