[PATCH 5.15 639/779] tty: serial: fsl_lpuart: correct the count of break characters

From: Greg Kroah-Hartman
Date: Mon Aug 15 2022 - 15:40:27 EST


From: Sherry Sun <sherry.sun@xxxxxxx>

[ Upstream commit 707f816f25590c20e056b3bd4a17ce69b03fe856 ]

The LPUART can't distinguish between a break signal and a framing error,
so need to count the break characters if there is a framing error and
received data is zero instead of the parity error.

Fixes: 5541a9bacfe5 ("serial: fsl_lpuart: handle break and make sysrq work")
Reviewed-by: Michael Walle <michael@xxxxxxxx>
Signed-off-by: Sherry Sun <sherry.sun@xxxxxxx>
Link: https://lore.kernel.org/r/20220725050115.12396-1-sherry.sun@xxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/tty/serial/fsl_lpuart.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 481107fdd69b..4155bd10711d 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -982,12 +982,12 @@ static void lpuart32_rxint(struct lpuart_port *sport)

if (sr & (UARTSTAT_PE | UARTSTAT_OR | UARTSTAT_FE)) {
if (sr & UARTSTAT_PE) {
+ sport->port.icount.parity++;
+ } else if (sr & UARTSTAT_FE) {
if (is_break)
sport->port.icount.brk++;
else
- sport->port.icount.parity++;
- } else if (sr & UARTSTAT_FE) {
- sport->port.icount.frame++;
+ sport->port.icount.frame++;
}

if (sr & UARTSTAT_OR)
@@ -1002,12 +1002,12 @@ static void lpuart32_rxint(struct lpuart_port *sport)
sr &= sport->port.read_status_mask;

if (sr & UARTSTAT_PE) {
+ flg = TTY_PARITY;
+ } else if (sr & UARTSTAT_FE) {
if (is_break)
flg = TTY_BREAK;
else
- flg = TTY_PARITY;
- } else if (sr & UARTSTAT_FE) {
- flg = TTY_FRAME;
+ flg = TTY_FRAME;
}

if (sr & UARTSTAT_OR)
--
2.35.1