[244/289] serial: mfd: adjust the baud rate setting

Greg KH
2010-12-08T01:03:42Z

From: Feng Tang <feng.tang@intel.com>

commit a5880a9e5bb40fbae55de60051d69a29091053c3 upstream.

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 <feng.tang@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/serial/mfd.c | 18 ++++++++----------
1 file changed, 8 insertions(+), 10 deletions(-)

--- a/drivers/serial/mfd.c
+++ b/drivers/serial/mfd.c
@@ -892,8 +892,7 @@ serial_hsu_set_termios(struct uart_port
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:
@@ -937,20 +936,19 @@ serial_hsu_set_termios(struct uart_port
ps = 0xC;
quot = 1;
break;
- case 2500000:
- mul = 0x2710;
- ps = 0x10;
- quot = 1;
- break;
case 18432000:
mul = 0x2400;
ps = 0x10;
quot = 1;
break;
+ case 3000000:
+ case 2500000:
+ case 2000000:
case 1500000:
- mul = 0x1D4C;
- ps = 0xc;
- quot = 1;
+ case 1000000:
+ case 500000:
+ /* mul/ps/quot = 0x9C4/0x10/0x1 will make a 500000 bps */
+ mul = baud / 500000 * 0x9C4;
break;
default:
;