[ Upstream commit ae9847f48a4b4bff0335da20be63ac84d94eb54c ]
GPIOs with no programmable direction are not required to implement
direction_output nor direction_input.
If we try to set an output direction on an output-only GPIO or input
direction on an input-only GPIO simply return 0.
This allows this single direction GPIO to be used by libgpiod.
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>