From 29788ab1d2bf26c130de8f44f9553ee78a27e8d5 Mon Sep 17 00:00:00 2001
From: Peng Fan <peng.fan@nxp.com>
Date: Tue, 29 Sep 2020 17:55:09 +0800
Subject: [PATCH] tty: serial: fsl_lpuart: fix lpuart32_poll_get_char
Git-commit: 29788ab1d2bf26c130de8f44f9553ee78a27e8d5
Patch-mainline: v5.10-rc1
References: git-fixes
The watermark is set to 1, so we need to input two chars to trigger RDRF
using the original logic. With the new logic, we could always get the
char when there is data in FIFO.
Suggested-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/20200929095509.21680-1-peng.fan@nxp.com
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/fsl_lpuart.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 645bbb24b433..590c901a1fc5 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -680,7 +680,7 @@ static void lpuart32_poll_put_char(struct uart_port *port, unsigned char c)
static int lpuart32_poll_get_char(struct uart_port *port)
{
- if (!(lpuart32_read(port, UARTSTAT) & UARTSTAT_RDRF))
+ if (!(lpuart32_read(port, UARTWATER) >> UARTWATER_RXCNT_OFF))
return NO_POLL_CHAR;
return lpuart32_read(port, UARTDATA);
--
2.16.4