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@xxxxxxxxx> --- .../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 -- 2.39.2