drm/bridge: parade-ps8640: Enable runtime power management
Fit ps8640 driver into runtime power management framework: First, break _poweron() to 3 parts: (1) turn on power and wait for ps8640's internal MCU to finish init (2) check panel HPD (which is proxied by GPIO9) (3) the other configs. As runtime_resume() can be called before panel is powered, we only add (1) to _resume() and leave (2)(3) to _pre_enable(). We also add (2) to _aux_transfer() as we want to ensure panel HPD is asserted before we start AUX CH transactions. Second, the original driver has a mysterious delay of 50 ms between (2) and (3). Since Parade's support can't explain what the delay is for, and we don't see removing the delay break any boards at hand, remove the delay to fit into this driver change. In addition, rename "powered" to "pre_enabled" and don't check for it in the pm_runtime calls. The pm_runtime calls are already refcounted so there's no reason to check there. The other user of "powered", _get_edid(), only cares if pre_enable() has already been called. Lastly, change some existing DRM_...() logging to dev_...() along the way, since DRM_...() seem to be deprecated in [1]. [1] https://patchwork.freedesktop.org/patch/454760/ Signed-off-by:Philip Chen <philipchen@chromium.org> Reviewed-by: