+ /* drop DTR and RTS */
+ spin_lock_irqsave(&priv->lock, flags);
+ if (on)
+ priv->line_control |= CH341_BIT_RTS | CH341_BIT_DTR;
+ else
+ priv->line_control &= ~(CH341_BIT_RTS | CH341_BIT_DTR);
+ spin_unlock_irqrestore(&priv->lock, flags);
+ ch341_set_handshake(port->serial->dev, priv->line_control);
+ wake_up_interruptible(&priv->delta_msr_wait);
+}
+
+static void ch341_close(struct usb_serial_port *port)
+{
+ dbg("%s - port %d", __func__, port->number);