Hi,

I started work on updating GPIO API and introducing PINCTRL API. The
initial proposal is described here:
https://github.com/zephyrproject-rtos/zephyr/issues/15611

Since the hardware implementation of GPIO and PINCTRL subsystem vary
widely between different vendors and even SoC families providing a
generic API becomes a relatively complex issue. I would like to deal
with it in a few stages:

- update GPIO API configuration options, e.g. defining pin pull-up, open
source configuration.

- extend GPIO API to support port operations

- add PINCTRL API

Issue #15611 deals only with the first part of the rework. It would be
great if some more developers could review it and leave their comments
on the issue page.

Thanks and regards,
Piotr