diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index eca02e8bd6d1..4c86aaf9c121 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -197,6 +197,8 @@ static void dw8250_set_divisor(struct uart_port *p, unsigned int baud,
 	if (ret < 0)
 		return;
 
+	__dw8250_set_divisor(p, quot_frac);
+
 	serial_port_out(p, UART_LCR, up->lcr | UART_LCR_DLAB);
 	if (!(serial_port_in(p, UART_LCR) & UART_LCR_DLAB))
 		goto idle_failed;
diff --git a/drivers/tty/serial/8250/8250_dwlib.c b/drivers/tty/serial/8250/8250_dwlib.c
index 9bb02a4ab11f..325793f20256 100644
--- a/drivers/tty/serial/8250/8250_dwlib.c
+++ b/drivers/tty/serial/8250/8250_dwlib.c
@@ -36,10 +36,20 @@ static unsigned int dw8250_get_divisor(struct uart_port *p, unsigned int baud,
 	return quot;
 }
 
+/* Program the fractional part of the divisor, if the UART has one */
+void __dw8250_set_divisor(struct uart_port *p, unsigned int quot_frac)
+{
+	struct dw8250_port_data *d = p->private_data;
+
+	if (d->dlf_size)
+		dw8250_writel_ext(p, DW_UART_DLF, quot_frac);
+}
+EXPORT_SYMBOL_GPL(__dw8250_set_divisor);
+
 static void dw8250_set_divisor(struct uart_port *p, unsigned int baud,
 			       unsigned int quot, unsigned int quot_frac)
 {
-	dw8250_writel_ext(p, DW_UART_DLF, quot_frac);
+	__dw8250_set_divisor(p, quot_frac);
 	serial8250_do_set_divisor(p, baud, quot);
 }
 
@@ -218,7 +228,9 @@ void dw8250_setup_port(struct uart_port *p)
 	if (reg) {
 		pd->dlf_size = fls(reg);
 		p->get_divisor = dw8250_get_divisor;
-		p->set_divisor = dw8250_set_divisor;
+		/* Keep a hook the driver has already installed */
+		if (!p->set_divisor)
+			p->set_divisor = dw8250_set_divisor;
 	}
 
 	reg = dw8250_readl_ext(p, DW_UART_UCV);
diff --git a/drivers/tty/serial/8250/8250_dwlib.h b/drivers/tty/serial/8250/8250_dwlib.h
index 39fcb1b323ad..4bb0ccb3e8ef 100644
--- a/drivers/tty/serial/8250/8250_dwlib.h
+++ b/drivers/tty/serial/8250/8250_dwlib.h
@@ -99,6 +99,7 @@ struct dw8250_port_data {
 
 void dw8250_do_set_termios(struct uart_port *p, struct ktermios *termios, const struct ktermios *old);
 void dw8250_setup_port(struct uart_port *p);
+void __dw8250_set_divisor(struct uart_port *p, unsigned int quot_frac);
 
 static inline u32 dw8250_readl_ext(struct uart_port *p, int offset)
 {