From a5880a9e5bb40fbae55de60051d69a29091053c3 Mon Sep 17 00:00:00 2001 From: Feng Tang Date: Fri, 19 Nov 2010 11:01:48 +0800 Subject: [PATCH] serial: mfd: adjust the baud rate setting Previous baud rate setting code only has been tested with 3.5M/9600/ 115200/230400/460800 bps, and recently we got a 3M bps device to test, which needs to modify current MUL register setting, and with this patch 2.5M/2M/1.5M/1M/0.5M should also work as they just use a MUL value scale down from 3M's. Also got some reference register setting from silicon guys for different baud rates, which tries to keep the pre-scalar register value to 16. Signed-off-by: Feng Tang Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/serial/mfd.c | 24 ++++++++---------------- 1 file changed, 8 insertions(+), 16 deletions(-) diff --git a/drivers/serial/mfd.c b/drivers/serial/mfd.c index 5fc699e929dc..d40010a22ecd 100644 --- a/drivers/serial/mfd.c +++ b/drivers/serial/mfd.c @@ -900,8 +900,7 @@ serial_hsu_set_termios(struct uart_port *port, struct ktermios *termios, unsigned char cval, fcr = 0; unsigned long flags; unsigned int baud, quot; - u32 mul = 0x3600; - u32 ps = 0x10; + u32 ps, mul; switch (termios->c_cflag & CSIZE) { case CS5: @@ -943,31 +942,24 @@ serial_hsu_set_termios(struct uart_port *port, struct ktermios *termios, baud = uart_get_baud_rate(port, termios, old, 0, 4000000); quot = 1; + ps = 0x10; + mul = 0x3600; switch (baud) { case 3500000: mul = 0x3345; ps = 0xC; break; - case 3000000: - mul = 0x2EE0; - break; - case 2500000: - mul = 0x2710; - break; - case 2000000: - mul = 0x1F40; - break; case 1843200: mul = 0x2400; break; + case 3000000: + case 2500000: + case 2000000: case 1500000: - mul = 0x1770; - break; case 1000000: - mul = 0xFA0; - break; case 500000: - mul = 0x7D0; + /* mul/ps/quot = 0x9C4/0x10/0x1 will make a 500000 bps */ + mul = baud / 500000 * 0x9C4; break; default: /* Use uart_get_divisor to get quot for other baud rates */ -- 2.34.1