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 <warthog618@gmail.com>
Link: https://lore.kernel.org/r/20240626052925.174272-5-warthog618@gmail.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
This commit is contained in:
Kent Gibson 2024-06-26 13:29:25 +08:00 committed by Bartosz Golaszewski
parent e48fe75afa
commit 6a9c15083b

View File

@ -35,11 +35,14 @@ Description
Update the configuration of previously requested lines, without releasing the Update the configuration of previously requested lines, without releasing the
line or introducing potential glitches. 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 The same :ref:`gpio-v2-get-line-config-rules` and
:ref:`gpio-v2-get-line-config-support` that apply when requesting the lines :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 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 bi-directional lines between input and output, but it may also be used to