From: Lukas Wunner <lukas@wunner.de>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Jiri Slaby <jslaby@suse.com>, Rob Herring <robh+dt@kernel.org>
Cc: "Matwey V. Kornilov" <matwey@sai.msu.ru>,
Giulio Benetti <giulio.benetti@micronovasrl.com>,
Heiko Stuebner <heiko@sntech.de>,
Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
Christoph Muellner <christoph.muellner@theobroma-systems.com>,
linux-serial@vger.kernel.org, devicetree@vger.kernel.org
Subject: [PATCH v2 0/4] rs485 bus termination GPIO
Date: Tue, 12 May 2020 14:40:00 +0200 [thread overview]
Message-ID: <cover.1589285873.git.lukas@wunner.de> (raw)
Define a device tree binding for an rs485 bus termination GPIO
(patch [3/4]), amend the serial core to retrieve the GPIO from
the device tree and amend the default ->rs485_config() callback
for 8250 drivers to change the GPIO on request from user space
(patch [4/4]).
Retrieving the GPIO from the device tree may fail, so allow
uart_get_rs485_mode() to return an errno and change all callers
to check for failure (patch [2/4]).
Fix a bug in the 8250 core if retrieval of the GPIO initially
fails with -EPROBE_DEFER and is later retried (patch [1/4]).
Changes v1 -> v2:
Patch [1/4]:
* Drop unnecessary "else" after "if ... goto" statement. (Andy)
* Document applicability to older kernels in commit message. (Andy)
* Add Fixes tag. (Andy)
Patch [4/4]:
* Drop unnecessary devm_gpiod_put(). (Andy)
* Use GPIOD_OUT_LOW macro for brevity. (Andy)
* Document the rationale for disabling termination by default.
* Drop nonsensical read of GPIO after setting its direction to out.
Link to v1:
https://lore.kernel.org/linux-serial/cover.1588505407.git.lukas@wunner.de/
Lukas Wunner (4):
serial: 8250: Avoid error message on reprobe
serial: Allow uart_get_rs485_mode() to return errno
dt-bindings: serial: Add binding for rs485 bus termination GPIO
serial: 8250: Support rs485 bus termination GPIO
.../devicetree/bindings/serial/rs485.yaml | 4 ++++
drivers/tty/serial/8250/8250_core.c | 18 ++++++++++-----
drivers/tty/serial/8250/8250_port.c | 4 ++++
drivers/tty/serial/ar933x_uart.c | 6 +++--
drivers/tty/serial/atmel_serial.c | 6 +++--
drivers/tty/serial/fsl_lpuart.c | 5 ++++-
drivers/tty/serial/imx.c | 6 ++++-
drivers/tty/serial/omap-serial.c | 4 +++-
drivers/tty/serial/serial_core.c | 22 ++++++++++++++++++-
drivers/tty/serial/stm32-usart.c | 8 +++----
include/linux/serial_core.h | 4 +++-
11 files changed, 69 insertions(+), 18 deletions(-)
--
2.26.2
next reply other threads:[~2020-05-12 12:40 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-12 12:40 Lukas Wunner [this message]
2020-05-12 12:40 ` [PATCH v2 1/4] serial: 8250: Avoid error message on reprobe Lukas Wunner
2020-05-12 13:45 ` Andy Shevchenko
2020-05-12 12:40 ` [PATCH v2 2/4] serial: Allow uart_get_rs485_mode() to return errno Lukas Wunner
2020-05-12 13:46 ` Andy Shevchenko
2020-05-12 12:40 ` [PATCH v2 3/4] dt-bindings: serial: Add binding for rs485 bus termination GPIO Lukas Wunner
2020-05-12 12:40 ` [PATCH v2 4/4] serial: 8250: Support " Lukas Wunner
2020-05-12 14:09 ` Andy Shevchenko
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=cover.1589285873.git.lukas@wunner.de \
--to=lukas@wunner.de \
--cc=andriy.shevchenko@linux.intel.com \
--cc=christoph.muellner@theobroma-systems.com \
--cc=devicetree@vger.kernel.org \
--cc=giulio.benetti@micronovasrl.com \
--cc=gregkh@linuxfoundation.org \
--cc=heiko@sntech.de \
--cc=jslaby@suse.com \
--cc=linux-serial@vger.kernel.org \
--cc=matwey@sai.msu.ru \
--cc=robh+dt@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).