From df57cf6a879502cd6e5559c1f2d6db12128e074f Mon Sep 17 00:00:00 2001 From: Stefan Wahren Date: Tue, 11 Aug 2015 11:46:01 +0000 Subject: [PATCH] serial: mxs-auart: fix baud rate range Currently mxs-auart doesn't care correctly about the baud rate divisor. According to reference manual the baud rate divisor must be between 0x000000EC and 0x003FFFC0. So calculate the possible baud rate range and use it for uart_get_baud_rate(). Signed-off-by: Stefan Wahren Reviewed-by: Fabio Estevam Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/mxs-auart.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c index 8d1cd158ca24..7c7f30809849 100644 --- a/drivers/tty/serial/mxs-auart.c +++ b/drivers/tty/serial/mxs-auart.c @@ -100,6 +100,8 @@ #define AUART_CTRL2_TXE (1 << 8) #define AUART_CTRL2_UARTEN (1 << 0) +#define AUART_LINECTRL_BAUD_DIV_MAX 0x003fffc0 +#define AUART_LINECTRL_BAUD_DIV_MIN 0x000000ec #define AUART_LINECTRL_BAUD_DIVINT_SHIFT 16 #define AUART_LINECTRL_BAUD_DIVINT_MASK 0xffff0000 #define AUART_LINECTRL_BAUD_DIVINT(v) (((v) & 0xffff) << 16) @@ -659,7 +661,7 @@ static void mxs_auart_settermios(struct uart_port *u, { struct mxs_auart_port *s = to_auart_port(u); u32 bm, ctrl, ctrl2, div; - unsigned int cflag, baud; + unsigned int cflag, baud, baud_min, baud_max; cflag = termios->c_cflag; @@ -752,7 +754,9 @@ static void mxs_auart_settermios(struct uart_port *u, } /* set baud rate */ - baud = uart_get_baud_rate(u, termios, old, 0, u->uartclk); + baud_min = DIV_ROUND_UP(u->uartclk * 32, AUART_LINECTRL_BAUD_DIV_MAX); + baud_max = u->uartclk * 32 / AUART_LINECTRL_BAUD_DIV_MIN; + baud = uart_get_baud_rate(u, termios, old, baud_min, baud_max); div = u->uartclk * 32 / baud; ctrl |= AUART_LINECTRL_BAUD_DIVFRAC(div & 0x3F); ctrl |= AUART_LINECTRL_BAUD_DIVINT(div >> 6); -- 2.20.1