[PATCH 01/10] serial: mvebu-uart: fix calculation of clock divisor

From: Pali Rohár
Date: Thu Jun 24 2021 - 18:50:07 EST


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

diff --git a/drivers/tty/serial/mvebu-uart.c b/drivers/tty/serial/mvebu-uart.c
index e0c00a1b0763..f81bfdaa608c 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;
--
2.20.1