From 6a9c15083b1662a4b7b36e787272deb696d72c24 Mon Sep 17 00:00:00 2001 From: Kent Gibson Date: Wed, 26 Jun 2024 13:29:25 +0800 Subject: [PATCH] Documentation: gpio: Reconfiguration with unset direction (uAPI v2) Update description of reconfiguration rules, adding requirement that a direction flag be set to enable changing configuration for a line. Signed-off-by: Kent Gibson Link: https://lore.kernel.org/r/20240626052925.174272-5-warthog618@gmail.com Signed-off-by: Bartosz Golaszewski --- .../userspace-api/gpio/gpio-v2-line-set-config-ioctl.rst | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/Documentation/userspace-api/gpio/gpio-v2-line-set-config-ioctl.rst b/Documentation/userspace-api/gpio/gpio-v2-line-set-config-ioctl.rst index 9b942a8a53ca..cfaab801556c 100644 --- a/Documentation/userspace-api/gpio/gpio-v2-line-set-config-ioctl.rst +++ b/Documentation/userspace-api/gpio/gpio-v2-line-set-config-ioctl.rst @@ -35,11 +35,14 @@ Description Update the configuration of previously requested lines, without releasing the line or introducing potential glitches. -The new configuration must specify the configuration of all requested lines. +The new configuration must specify a configuration for all requested lines. The same :ref:`gpio-v2-get-line-config-rules` and :ref:`gpio-v2-get-line-config-support` that apply when requesting the lines -also apply when updating the line configuration. +also apply when updating the line configuration, with the additional +restriction that a direction flag must be set to enable reconfiguration. +If no direction flag is set in the configuration for a given line then the +configuration for that line is left unchanged. The motivating use case for this command is changing direction of bi-directional lines between input and output, but it may also be used to