[PATCH 4.19 41/78] serial: fsl_lpuart: fix maximum acceptable baud rate with over-sampling

From: Greg Kroah-Hartman
Date: Mon Mar 04 2019 - 03:29:42 EST


4.19-stable review patch. If anyone has any objections, please let me know.

------------------

[ Upstream commit 815d835b7ba46685c316b000013367dacb2b461b ]

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

Signed-off-by: Tomonori Sakita <tomonori.sakita@xxxxxxxxxx>
Signed-off-by: Atsushi Nemoto <atsushi.nemoto@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/tty/serial/fsl_lpuart.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 7d030c2e42ffd..50b6746a8b5d7 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -1695,7 +1695,7 @@ lpuart32_set_termios(struct uart_port *port, struct ktermios *termios,
}

/* 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);

--
2.19.1