From 5b9cea15a3de5d65000d49f626b71b00d42a0577 Mon Sep 17 00:00:00 2001 From: Lanqing Liu Date: Tue, 19 Feb 2019 15:31:11 +0800 Subject: serial: sprd: Modify the baud rate calculation formula When the source clock is not divisible by the expected baud rate and the remainder is not less than half of the expected baud rate, the old formular will round up the frequency division coefficient. This will make the actual baud rate less than the expected value and can not meet the external transmission requirements. Thus this patch modifies the baud rate calculation formula to support the serial controller output the maximum baud rate. Signed-off-by: Lanqing Liu Signed-off-by: Baolin Wang Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/sprd_serial.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/tty/serial') diff --git a/drivers/tty/serial/sprd_serial.c b/drivers/tty/serial/sprd_serial.c index 4287ca305b6b..1891a45ac05d 100644 --- a/drivers/tty/serial/sprd_serial.c +++ b/drivers/tty/serial/sprd_serial.c @@ -371,7 +371,7 @@ static void sprd_set_termios(struct uart_port *port, /* ask the core to calculate the divisor for us */ baud = uart_get_baud_rate(port, termios, old, 0, SPRD_BAUD_IO_LIMIT); - quot = (unsigned int)((port->uartclk + baud / 2) / baud); + quot = port->uartclk / baud; /* set data length */ switch (termios->c_cflag & CSIZE) { -- cgit v1.2.3