This is a note to let you know that I've just added the patch titled
tty: serial: fsl_lpuart: fix lpuart32_poll_get_char
to the 5.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tty-serial-fsl_lpuart-fix-lpuart32_poll_get_char.patch
and it can be found in the queue-5.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 29788ab1d2bf26c130de8f44f9553ee78a27e8d5 Mon Sep 17 00:00:00 2001
From: Peng Fan <peng.fan@xxxxxxx>
Date: Tue, 29 Sep 2020 17:55:09 +0800
Subject: tty: serial: fsl_lpuart: fix lpuart32_poll_get_char
From: Peng Fan <peng.fan@xxxxxxx>
commit 29788ab1d2bf26c130de8f44f9553ee78a27e8d5 upstream.
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@xxxxxxx>
Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
Link: https://lore.kernel.org/r/20200929095509.21680-1-peng.fan@xxxxxxx
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/tty/serial/fsl_lpuart.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -680,7 +680,7 @@ static void lpuart32_poll_put_char(struc
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);
Patches currently in stable-queue which might be from peng.fan@xxxxxxx are
queue-5.9/tty-serial-fsl_lpuart-fix-lpuart32_poll_get_char.patch
queue-5.9/tty-serial-lpuart-fix-lpuart32_write-usage.patch
