Received-SPF: pass (google.com: domain of linux-kernel+bounces-147385-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) client-ip=2604:1380:4601:e00::3;
Date: Tue, 16 Apr 2024 18:29:28 +0000
To: linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Jiri Slaby <jirislaby@kernel.org>
From: Michael Pratt <mcpratt@pm.me>
Cc: Wander Lairson Costa <wander@redhat.com>, =?utf-8?Q?Ilpo_J=C3=A4rvinen?= <ilpo.jarvinen@linux.intel.com>, Andy Shevchenko <andriy.shevchenko@linux.intel.com>, Vamshi Gajjela <vamshigajjela@google.com>, Michael Pratt <mcpratt@pm.me>
Subject: [PATCH v2 1/3] serial: core: Store fifo timeout again
Message-ID: <20240416182741.22514-2-mcpratt@pm.me>
In-Reply-To: <20240416182741.22514-1-mcpratt@pm.me>
References: <20240416182741.22514-1-mcpratt@pm.me>
Feedback-ID: 27397442:user:proton
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable

This is a partial revert of Commit f9008285bb69
("serial: Drop timeout from uart_port").

In order to prevent having to calculate a timeout
for the fifo device during a write operation, if enabled,
calculate it ahead of time and store the value of the timeout
in a struct member of uart_port.

Signed-off-by: Michael Pratt <mcpratt@pm.me>
---
V1 -> V2: new commit

 drivers/tty/serial/serial_core.c | 3 +++
 include/linux/serial_core.h      | 1 +
 2 files changed, 4 insertions(+)

diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_c=
ore.c
index ff85ebd3a007..9b3176d684a4 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -414,6 +414,9 @@ uart_update_timeout(struct uart_port *port, unsigned in=
t cflag,
=20
 =09temp *=3D NSEC_PER_SEC;
 =09port->frame_time =3D (unsigned int)DIV64_U64_ROUND_UP(temp, baud);
+
+=09if (port->fifosize > 1)
+=09=09port->timeout =3D uart_fifo_timeout(port);
 }
 EXPORT_SYMBOL(uart_update_timeout);
=20
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 0a0f6e21d40e..c6422021152f 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -561,6 +561,7 @@ struct uart_port {
=20
 =09bool=09=09=09hw_stopped;=09=09/* sw-assisted CTS flow state */
 =09unsigned int=09=09mctrl;=09=09=09/* current modem ctrl settings */
+=09unsigned long=09=09timeout;=09=09/* character-based timeout */
 =09unsigned int=09=09frame_time;=09=09/* frame timing in ns */
 =09unsigned int=09=09type;=09=09=09/* port type */
 =09const struct uart_ops=09*ops;
--=20
2.30.2