serial: sh-sci: Make sure status register SCxSR is read in correct sequence
authorKazuhiro Fujita <kazuhiro.fujita.jg@renesas.com>
Fri, 27 Mar 2020 18:17:28 +0000 (18:17 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 29 Apr 2020 14:33:24 +0000 (16:33 +0200)
commit3af0614df15c1c1fbfafed4888f12d76a7b044e1
tree52eb9712e2d553cc2664c66373d449df412f6033
parentfceab238c534eca02253c01f3bd5db391acd47b0
serial: sh-sci: Make sure status register SCxSR is read in correct sequence

commit 3dc4db3662366306e54ddcbda4804acb1258e4ba upstream.

For SCIF and HSCIF interfaces the SCxSR register holds the status of
data that is to be read next from SCxRDR register, But where as for
SCIFA and SCIFB interfaces SCxSR register holds status of data that is
previously read from SCxRDR register.

This patch makes sure the status register is read depending on the port
types so that errors are caught accordingly.

Cc: <stable@vger.kernel.org>
Signed-off-by: Kazuhiro Fujita <kazuhiro.fujita.jg@renesas.com>
Signed-off-by: Hao Bui <hao.bui.yg@renesas.com>
Signed-off-by: KAZUMI HARADA <kazumi.harada.rh@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/1585333048-31828-1-git-send-email-kazuhiro.fujita.jg@renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/tty/serial/sh-sci.c