serial: sh-sci: support lower baud rate
authorTakashi Yoshii <takashi.yoshii.zj@renesas.com>
Fri, 16 Nov 2012 01:52:49 +0000 (10:52 +0900)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 16 Nov 2012 02:02:37 +0000 (18:02 -0800)
commit9d482cc353bd0391730730b26e4c2938dc90e477
tree41e37908c1d0eca6e9a19ecbb39c49a6585cb42b
parent4ffc3cdb642823ebee84538addac7cde1174e314
serial: sh-sci: support lower baud rate

Support prescaler 1/16 and 1/64, in addition to current 1 and 1/4.

Supporting below 2400bps was dropped long time ago in mainline.
Since then, setting lower rate has been resulting in erroneous
register value, without indicating any errors through API.

This patch adds more prescaler to support lower rates again.
This still doesn't check range, but we won't hit the case because
even 50bps at 48MHz clock is now supported.

Signed-off-by: Takashi Yoshii <takashi.yoshii.zj@renesas.com>
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/tty/serial/sh-sci.c