Since 39b2bbe3d715 (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.

Use this to simplify the driver. Furthermore this is one caller less
that stops us making the flags argument to gpiod_get*() mandatory.

Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-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>

Signed-off-by: Rob Clark <robdclark@gmail.com>

wait_for_completion_timeout returns 0 in case of timeout and never
return < 0 so there is no additional information in printing the
value of time_left here as it will always be 0, thus it can be dropped.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

wait_for_completion_timeout returns >= 0 but never
negative  - so the error check should be against equality
to 0 not <= 0.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

return type of wait_for_completion_timeout is unsigned long not int, this
patch assigns the return value of wait_for_completion_timeout to an
appropriately typed and named variable.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

Fix build warning when building edp/edp_aux.o due to missing
prototype for edp_aux_transfer.

This function is only used in edp_aux.c so just make it static.

Reported-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

wait_for_completion_timeout returns 0 in case of timeout so printing the
return value here will always yield 0 and is therefor redundant - dropped.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

The timeout is passed as a constant which makes it HZ dependent because
jiffies are expected so it should be converted to jiffies. The actual
value is not clear from the code - my best guess is that this should be
300 milliseconds given that other timeouts are in milliseconds based on
looking at other drm drivers (e.g. exynos_drm_dsi.c:356 300ms,
tegra/dpaux.c:188 250ms) - this needs to be confirmed by someone who
knows the details of the driver.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

wait_for_completion_timeout return >= 0 but never negative so the check
logic looks inconsistent. Further the return value of
wait_for_completion_timeout was being passed up the call chain but the
x call sites as drm_dp_i2c_do_msg()/drm_dp_dpcd_access() check for < 0
thus timeout was being treated as success case.

<snip> drivers/gpu/drm/drm_dp_helper.c:drm_dp_i2c_do_msg()
                mutex_lock(&aux->hw_mutex);
                ret = aux->transfer(aux, msg);
                mutex_unlock(&aux->hw_mutex);
                if (ret < 0) {
<snip>
logic in edp_aux_transfer() seems incorrect as it could return 0 (timeout)
but checks of <= 0 to indicate error so the return probably should be
-ETIMEDOUT in case wait_for_completion_timeout returns 0 (timeout
occurred).

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

Signed-off-by: Rob Clark <robdclark@gmail.com>