Update description of reconfiguration rules, adding requirement that a direction flag be set or the configuration is considered invalid. Signed-off-by: Kent Gibson <warthog618@xxxxxxxxx> --- .../userspace-api/gpio/gpio-handle-set-config-ioctl.rst | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/Documentation/userspace-api/gpio/gpio-handle-set-config-ioctl.rst b/Documentation/userspace-api/gpio/gpio-handle-set-config-ioctl.rst index d002a84681ac..a03f30db63ab 100644 --- a/Documentation/userspace-api/gpio/gpio-handle-set-config-ioctl.rst +++ b/Documentation/userspace-api/gpio/gpio-handle-set-config-ioctl.rst @@ -43,7 +43,10 @@ The configuration applies to all requested lines. The same :ref:`gpio-get-linehandle-config-rules` and :ref:`gpio-get-linehandle-config-support` that apply when requesting the -lines also apply when updating the line configuration. +lines also apply when updating the line configuration, with the additional +restriction that a direction flag must be set. Requesting an invalid +configuration, including without a direction flag set, is an error +(**EINVAL**). The motivating use case for this command is changing direction of bi-directional lines between input and output, but it may be used more -- 2.39.2
