Re: [PATCH 3/4] tty: serial: samsung: Increase maximum baudrate

From: Lee Jones
Date: Fri Dec 21 2018 - 05:16:00 EST


On Fri, 14 Dec 2018, Marek Szyprowski wrote:

> From: Seung-Woo Kim <sw0312.kim@xxxxxxxxxxx>
>
> This driver can be used to communicate with Bluetooth chip in high-speed
> UART mode, so increase the maximum baudrate to 3Mbps.
>
> Signed-off-by: Seung-Woo Kim <sw0312.kim@xxxxxxxxxxx>
> [mszyprow: rephrased commit message]
> Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
> ---
> drivers/tty/serial/samsung.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
> index 2a49b6d876b8..9fc3559f80d9 100644
> --- a/drivers/tty/serial/samsung.c
> +++ b/drivers/tty/serial/samsung.c
> @@ -1287,7 +1287,7 @@ static void s3c24xx_serial_set_termios(struct uart_port *port,
> * Ask the core to calculate the divisor for us.
> */
>
> - baud = uart_get_baud_rate(port, termios, old, 0, 115200*8);
> + baud = uart_get_baud_rate(port, termios, old, 0, 3000000);

Does that mean the low speed devices will stop working? It looks like
this should be dynamically configurable based on what device is
connected to it, no?

> quot = s3c24xx_serial_getclk(ourport, baud, &clk, &clk_sel);
> if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST)
> quot = port->custom_divisor;

--
Lee Jones [æçæ]
Linaro Services Technical Lead
Linaro.org â Open source software for ARM SoCs
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