This is a note to let you know that I've just added the patch titled
tty: serial: samsung: fix tx_empty() to return TIOCSER_TEMT
to the 5.10-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-samsung-fix-tx_empty-to-return-tiocser_te.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 7a4d2287ff1ba9a934ab897a1998bdf4e865ae26
Author: Tudor Ambarus <tudor.ambarus@xxxxxxxxxx>
Date: Fri Jan 19 10:45:08 2024 +0000
tty: serial: samsung: fix tx_empty() to return TIOCSER_TEMT
[ Upstream commit 314c2b399288f0058a8c5b6683292cbde5f1531b ]
The core expects for tx_empty() either TIOCSER_TEMT when the tx is
empty or 0 otherwise. s3c24xx_serial_txempty_nofifo() might return
0x4, and at least uart_get_lsr_info() tries to clear exactly
TIOCSER_TEMT (BIT(1)). Fix tx_empty() to return TIOCSER_TEMT.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxx>
Reviewed-by: Sam Protsenko <semen.protsenko@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240119104526.1221243-2-tudor.ambarus@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
index fa5b1321d9b15..5388eb7fa0f47 100644
--- a/drivers/tty/serial/samsung_tty.c
+++ b/drivers/tty/serial/samsung_tty.c
@@ -922,11 +922,10 @@ static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port)
if ((ufstat & info->tx_fifomask) != 0 ||
(ufstat & info->tx_fifofull))
return 0;
-
- return 1;
+ return TIOCSER_TEMT;
}
- return s3c24xx_serial_txempty_nofifo(port);
+ return s3c24xx_serial_txempty_nofifo(port) ? TIOCSER_TEMT : 0;
}
/* no modem control lines */
