diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index fe8a7c5fa0e9..1ab6bf48516f 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -1315,7 +1315,7 @@ static int update_mctrl(struct usb_serial_port *port, unsigned int set,
 
 
 static u32 get_ftdi_divisor(struct tty_struct *tty,
-						struct usb_serial_port *port)
+			    struct usb_serial_port *port, speed_t old_baud)
 {
 	struct ftdi_private *priv = usb_get_serial_port_data(port);
 	struct device *dev = &port->dev;
@@ -1338,6 +1338,8 @@ static u32 get_ftdi_divisor(struct tty_struct *tty,
 			__func__, priv->custom_divisor, baud);
 	}
 
+	if (!baud)
+		baud = old_baud;
 	if (!baud)
 		baud = 9600;
 	switch (priv->chip_type) {
@@ -1346,8 +1348,12 @@ static u32 get_ftdi_divisor(struct tty_struct *tty,
 		if (div_value == (u32)-1) {
 			dev_dbg(dev, "%s - Baudrate (%d) requested is not supported\n",
 				__func__,  baud);
-			baud = 9600;
+			baud = old_baud ? old_baud : 9600;
 			div_value = ftdi_sio_baud_to_divisor(baud);
+			if (div_value == -1) {
+				baud = 9600;
+				div_value = ftdi_sio_baud_to_divisor(baud);
+			}
 			div_okay = 0;
 		}
 		break;
@@ -1356,8 +1362,11 @@ static u32 get_ftdi_divisor(struct tty_struct *tty,
 			div_value = ftdi_232am_baud_to_divisor(baud);
 		} else {
 			dev_dbg(dev, "%s - Baud rate too high!\n", __func__);
-			baud = 9600;
-			div_value = ftdi_232am_baud_to_divisor(9600);
+			if (old_baud >= 183 && old_baud <= 3000000)
+				baud = old_baud;
+			else
+				baud = 9600;
+			div_value = ftdi_232am_baud_to_divisor(baud);
 			div_okay = 0;
 		}
 		break;
@@ -1379,9 +1388,12 @@ static u32 get_ftdi_divisor(struct tty_struct *tty,
 			div_value = ftdi_232bm_baud_to_divisor(baud);
 		} else {
 			dev_dbg(dev, "%s - Baud rate too high!\n", __func__);
-			div_value = ftdi_232bm_baud_to_divisor(9600);
+			if (old_baud >= 183 && old_baud <= 3000000)
+				baud = old_baud;
+			else
+				baud = 9600;
+			div_value = ftdi_232bm_baud_to_divisor(baud);
 			div_okay = 0;
-			baud = 9600;
 		}
 		break;
 	case FT2232H: /* FT2232H chip */
@@ -1393,9 +1405,17 @@ static u32 get_ftdi_divisor(struct tty_struct *tty,
 			div_value = ftdi_232bm_baud_to_divisor(baud);
 		} else {
 			dev_dbg(dev, "%s - Baud rate too high!\n", __func__);
-			div_value = ftdi_232bm_baud_to_divisor(9600);
+			if (old_baud >= 183 && old_baud < 1200) {
+				baud = old_baud;
+				div_value = ftdi_232bm_baud_to_divisor(baud);
+			} else {
+				if (old_baud >= 1200 && old_baud <= 12000000)
+					baud = old_baud;
+				else
+					baud = 9600;
+				div_value = ftdi_2232h_baud_to_divisor(baud);
+			}
 			div_okay = 0;
-			baud = 9600;
 		}
 		break;
 	} /* priv->chip_type */
@@ -1410,7 +1430,7 @@ static u32 get_ftdi_divisor(struct tty_struct *tty,
 	return div_value;
 }
 
-static int change_speed(struct tty_struct *tty, struct usb_serial_port *port)
+static int change_speed(struct tty_struct *tty, struct usb_serial_port *port, speed_t old_baud)
 {
 	struct ftdi_private *priv = usb_get_serial_port_data(port);
 	u16 value;
@@ -1418,7 +1438,7 @@ static int change_speed(struct tty_struct *tty, struct usb_serial_port *port)
 	u32 index_value;
 	int rv;
 
-	index_value = get_ftdi_divisor(tty, port);
+	index_value = get_ftdi_divisor(tty, port, old_baud);
 	value = (u16)index_value;
 	index = (u16)(index_value >> 16);
 	if (priv->chip_type == FT2232C || priv->chip_type == FT2232H ||
@@ -1541,7 +1561,7 @@ static int set_serial_info(struct tty_struct *tty, struct serial_struct *ss)
 		if (priv->flags & ASYNC_SPD_MASK)
 			dev_warn_ratelimited(&port->dev, "use of SPD flags is deprecated\n");
 
-		change_speed(tty, port);
+		change_speed(tty, port, 9600);
 	}
 	mutex_unlock(&priv->cfg_lock);
 	return 0;
@@ -2790,9 +2810,12 @@ static void ftdi_set_termios(struct tty_struct *tty,
 		/* Drop RTS and DTR */
 		clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);
 	} else {
+		speed_t old_baud =
+			old_termios ? tty_termios_baud_rate(old_termios) : 9600;
+
 		/* set the baudrate determined before */
 		mutex_lock(&priv->cfg_lock);
-		if (change_speed(tty, port))
+		if (change_speed(tty, port, old_baud))
 			dev_err(ddev, "%s urb failed to set baudrate\n", __func__);
 		mutex_unlock(&priv->cfg_lock);
 		/* Ensure RTS and DTR are raised when baudrate changed from 0 */
