Since 39b2bbe3d7 (gpio: add flags argument to gpiod_get*() functions)
which appeared in v3.17-rc1, the gpiod_get* functions take an additional
parameter that allows to specify direction and initial value for output.
Also there is a variant to find optional gpios that returns NULL if
there is no gpio instead of -ENOENT.
Make use of both features to simplify the driver.
This makes error checking more strict because errors like -ENOSYS ("no
gpio support compiled in") or -EPROBE_DEFER ("gpio not ready yet") are
handled correctly now.
Furthermore this is one caller less that stops us making the flags
argument to gpiod_get*() mandatory.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Rob Clark <robdclark@gmail.com>
9590e69db9