This is a note to let you know that I've just added the patch titled
serial: fixup backport of "serial: Deassert Transmit Enable on probe in driver-specific way"
to the 5.15-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:
serial-fixup-backport-of-serial-deassert-transmit-enable-on-probe-in-driver-specific-way.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From linux@xxxxxxxxxxxxxxxxxx Thu Jan 12 13:40:41 2023
From: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
Date: Thu, 22 Dec 2022 12:44:14 +0100
Subject: serial: fixup backport of "serial: Deassert Transmit Enable on probe in driver-specific way"
To: "Greg Kroah-Hartman" <gregkh@xxxxxxxxxxxxxxxxxxx>, "Jiri Slaby" <jirislaby@xxxxxxxxxx>, "Lukas Wunner" <lukas@xxxxxxxxx>, "Dominique Martinet" <dominique.martinet@xxxxxxxxxxxxxxxxx>, "Daisuke Mizobuchi" <mizo@xxxxxxxxxxxxxxxxx>, "Ilpo Järvinen" <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Cc: linux-serial@xxxxxxxxxxxxxxx, stable@xxxxxxxxxxxxxxx, Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
Message-ID: <20221222114414.1886632-1-linux@xxxxxxxxxxxxxxxxxx>
From: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
When 7c7f9bc986e6 ("serial: Deassert Transmit Enable on probe in
driver-specific way") got backported to 5.15.y, there known as
b079d3775237, some hunks were accidentally left out.
In fsl_lpuart.c, this amounts to uart_remove_one_port() being called
in an error path despite uart_add_one_port() not having been called.
In serial_core.c, it is possible that the omission in
uart_suspend_port() is harmless, but the backport did have the
corresponding hunk in uart_resume_port(), it runs counter to the
original commit's intention of
Skip any invocation of ->set_mctrl() if RS485 is enabled.
and it's certainly better to be aligned with upstream.
Fixes: b079d3775237 ("serial: Deassert Transmit Enable on probe in driver-specific way")
Signed-off-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Dominique MARTINET <dominique.martinet@xxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/tty/serial/fsl_lpuart.c | 2 +-
drivers/tty/serial/serial_core.c | 3 ++-
2 files changed, 3 insertions(+), 2 deletions(-)
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -2784,9 +2784,9 @@ static int lpuart_probe(struct platform_
return 0;
failed_irq_request:
-failed_get_rs485:
uart_remove_one_port(&lpuart_reg, &sport->port);
failed_attach_port:
+failed_get_rs485:
failed_reset:
lpuart_disable_clks(sport);
return ret;
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -2225,7 +2225,8 @@ int uart_suspend_port(struct uart_driver
spin_lock_irq(&uport->lock);
ops->stop_tx(uport);
- ops->set_mctrl(uport, 0);
+ if (!(uport->rs485.flags & SER_RS485_ENABLED))
+ ops->set_mctrl(uport, 0);
ops->stop_rx(uport);
spin_unlock_irq(&uport->lock);
Patches currently in stable-queue which might be from linux@xxxxxxxxxxxxxxxxxx are
queue-5.15/serial-fixup-backport-of-serial-deassert-transmit-enable-on-probe-in-driver-specific-way.patch
