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From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org,
        =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org>
Subject: [PATCH 5.12 094/700] serial: mvebu-uart: fix calculation of clock divisor
Date:   Mon, 12 Jul 2021 08:02:57 +0200
Message-Id: <20210712060938.075288830@linuxfoundation.org>
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From: Pali Rohár <pali@kernel.org>

commit 9078204ca5c33ba20443a8623a41a68a9995a70d upstream.

The clock divisor should be rounded to the closest value.

Signed-off-by: Pali Rohár <pali@kernel.org>
Fixes: 68a0db1d7da2 ("serial: mvebu-uart: add function to change baudrate")
Cc: stable@vger.kernel.org # 0e4cf69ede87 ("serial: mvebu-uart: clarify the baud rate derivation")
Link: https://lore.kernel.org/r/20210624224909.6350-2-pali@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/tty/serial/mvebu-uart.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- 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(stru
 	 * 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;