From: Vabhav Sharma Date: Fri, 26 Jun 2020 11:20:34 +0000 (+0530) Subject: tty: serial: fsl_lpuart: minimum baud rate support X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=d10ee1d1917b082f0008a840cde5aeaad11b396b;p=linux.git tty: serial: fsl_lpuart: minimum baud rate support The formula for the baud rate is baud rate = "baud clock / ((OSR+1) × SBR) Algorithm used in function lpuart32_serial_setbrg() only changes the SBR. Even with maxmum value put in, OSR stays at 0x7 and the lowest baud rate would be ~ 2600 bps Update the algorithm to allow driver operation at 1200,2400 or 600 bps Signed-off-by: Vabhav Sharma Link: https://lore.kernel.org/r/1593170434-13524-1-git-send-email-vabhav.sharma@oss.nxp.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index 90298c4030421..7ca6422492241 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -1925,6 +1925,9 @@ static void __lpuart32_serial_setbrg(struct uart_port *port, tmp_sbr++; } + if (tmp_sbr > UARTBAUD_SBR_MASK) + continue; + if (tmp_diff <= baud_diff) { baud_diff = tmp_diff; osr = tmp_osr;