From: Kazuhiro Fujita <[email protected]>

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: <[email protected]>
Signed-off-by: Kazuhiro Fujita <[email protected]>
Signed-off-by: Hao Bui <[email protected]>
Signed-off-by: KAZUMI HARADA <[email protected]>
Signed-off-by: Lad Prabhakar <[email protected]>
Tested-by: Geert Uytterhoeven <[email protected]>
Link: 
https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/tty/serial/sh-sci.c |   11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -873,9 +873,16 @@ static void sci_receive_chars(struct uar
                                tty_insert_flip_char(tport, c, TTY_NORMAL);
                } else {
                        for (i = 0; i < count; i++) {
-                               char c = serial_port_in(port, SCxRDR);
+                               char c;
 
-                               status = serial_port_in(port, SCxSR);
+                               if (port->type == PORT_SCIF ||
+                                   port->type == PORT_HSCIF) {
+                                       status = serial_port_in(port, SCxSR);
+                                       c = serial_port_in(port, SCxRDR);
+                               } else {
+                                       c = serial_port_in(port, SCxRDR);
+                                       status = serial_port_in(port, SCxSR);
+                               }
                                if (uart_handle_sysrq_char(port, c)) {
                                        count--; i--;
                                        continue;


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