[PATCH 1/3] tty: serial: meson: Use DIV_ROUND_CLOSEST to calculate baud rates

[Yu Tu]

Due to chip process differences, chip designers recommend using baud
rates as close to and larger as possible in order to reduce clock
errors.

Signed-off-by: Yu Tu <yu.tu at amlogic.com>
---
 drivers/tty/serial/meson_uart.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c
index 2bf1c57e0981..8e59624935af 100644
--- a/drivers/tty/serial/meson_uart.c
+++ b/drivers/tty/serial/meson_uart.c
@@ -299,10 +299,10 @@ static void meson_uart_change_speed(struct uart_port *port, unsigned long baud)
 		cpu_relax();
 
 	if (port->uartclk == 24000000) {
-		val = ((port->uartclk / 3) / baud) - 1;
+		val = DIV_ROUND_CLOSEST(port->uartclk / 3, baud) - 1;
 		val |= AML_UART_BAUD_XTAL;
 	} else {
-		val = ((port->uartclk * 10 / (baud * 4) + 5) / 10) - 1;
+		val =  DIV_ROUND_CLOSEST(port->uartclk / 4, baud) - 1;
 	}
 	val |= AML_UART_BAUD_USE;
 	writel(val, port->membase + AML_UART_REG5);
-- 
2.33.1