The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 9078204ca5c33ba20443a8623a41a68a9995a70d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali@xxxxxxxxxx>
Date: Fri, 25 Jun 2021 00:49:00 +0200
Subject: [PATCH] serial: mvebu-uart: fix calculation of clock divisor
MIME-Version: 1.0
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The clock divisor should be rounded to the closest value.
Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
Fixes: 68a0db1d7da2 ("serial: mvebu-uart: add function to change baudrate")
Cc: stable@xxxxxxxxxxxxxxx # 0e4cf69ede87 ("serial: mvebu-uart: clarify the baud rate derivation")
Link: https://lore.kernel.org/r/20210624224909.6350-2-pali@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index 04c41689d81c..f3ecbcf495ee 100644
--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -463,7 +463,7 @@ static int mvebu_uart_baud_rate_set(struct uart_port *port, unsigned int baud)
* makes use of D to configure the desired baudrate.
*/
m_divisor = OSAMP_DEFAULT_DIVISOR;
- d_divisor = DIV_ROUND_UP(port->uartclk, baud * m_divisor);
+ d_divisor = DIV_ROUND_CLOSEST(port->uartclk, baud * m_divisor);
brdv = readl(port->membase + UART_BRDV);
brdv &= ~BRDV_BAUD_MASK;
