linux-kernel - [PATCH v2 0/2] i2c: improve bus recovery for single-ended GPIOs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20260125195123.248798-1-jie.i.li@nokia.com>
Date: Sun, 25 Jan 2026 20:51:21 +0100
From: Jie Li <lj29312931@...il.com>
To: wsa@...nel.org,
	linus.walleij@...aro.org
Cc: linux-i2c@...r.kernel.org,
	linux-gpio@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Jie Li <jie.i.li@...ia.com>
Subject: [PATCH v2 0/2] i2c: improve bus recovery for single-ended GPIOs

Greetings,

Apologies for the late reply, as things have been a bit hectic at work lately.

Thank you very much for the guidance and the suggestion to move the logic into
gpiolib. This is a far better approach than my initial one. As this is my first
time submitting code to the Linux community, I am very grateful for your
mentorship and support.

This series (v2) addresses a limitation in the I2C bus recovery 
mechanism where certain open-drain GPIOs are incorrectly identified 
as input-only, preventing the recovery logic from functioning.

Following the suggestion from Linus Walleij, this version drops the 
previously proposed "force-set-sda" DT property. Instead, it 
introduces a generic helper in the GPIO subsystem to identify 
single-ended configurations. This allows the I2C core to reliably 
enable recovery for open-drain lines regardless of the 
instantaneous hardware direction reporting.

Changes in v2:
- Replaced DT-based "force-set-sda" with a gpiolib helper.
- Added gpiod_is_single_ended() to drivers/gpio/gpiolib.c.
- Updated i2c-core-base.c to use the new helper.

Jie Li (2):
  gpiolib: add gpiod_is_single_ended() helper
  i2c: core: support recovery for single-ended GPIOs

 drivers/gpio/gpiolib.c        | 22 ++++++++++++++++++++++
 drivers/i2c/i2c-core-base.c   |  3 ++-
 include/linux/gpio/consumer.h |  5 +++++
 3 files changed, 29 insertions(+), 1 deletion(-)

-- 
2.43.0