From 47ac76662ca9c5852fd353093f19de3ae85f2e66 Mon Sep 17 00:00:00 2001
From: Mark <dmarkh@cfl.rr.com>
Date: Sun, 12 Aug 2018 11:47:16 -0400
Subject: [PATCH] tty: serial: 8250: Revert NXP SC16C2552 workaround
Git-commit: 47ac76662ca9c5852fd353093f19de3ae85f2e66
Patch-mainline: v4.19-rc1
References: bsc#1051510

Revert commit ecb988a3b7985913d1f0112f66667cdd15e40711: tty: serial:
8250: 8250_core: NXP SC16C2552 workaround

The above commit causes userland application to no longer write
correctly its first write to a dumb terminal connected to /dev/ttyS0.
This commit seems to be the culprit. It's as though the TX FIFO is being
reset during that write. What should be displayed is:

PSW 80000000 INST 00000000                           HALT
//

What is displayed is some variation of:

T 00000000           HAL//

Reverting this commit via this patch fixes my problem.

Signed-off-by: Mark Hounschell <dmarkh@cfl.rr.com>
Fixes: ecb988a3b798 ("tty: serial: 8250: 8250_core: NXP SC16C2552 workaround")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/tty/serial/8250/8250_port.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 8d863004c0da..3f779d25ec0c 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -90,8 +90,7 @@ static const struct serial8250_config uart_config[] = {
 		.name		= "16550A",
 		.fifo_size	= 16,
 		.tx_loadsz	= 16,
-		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 |
-				  UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,
+		.fcr		= UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
 		.rxtrig_bytes	= {1, 4, 8, 14},
 		.flags		= UART_CAP_FIFO,
 	},
-- 
2.18.0