serial: fsl_lpuart: fix maximum acceptable baud rate with over-sampling

[ Upstream commit 815d835b7ba46685c316b000013367dacb2b461b ]

Using over-sampling ratio, lpuart can accept baud rate upto uartclk / 4.

Signed-off-by: Tomonori Sakita <tomonori.sakita@sord.co.jp>
Signed-off-by: Atsushi Nemoto <atsushi.nemoto@sord.co.jp>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 5c471c3..8009965 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -1494,7 +1494,7 @@
 	}
 
 	/* ask the core to calculate the divisor */
-	baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
+	baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 4);
 
 	spin_lock_irqsave(&sport->port.lock, flags);