Not sure if I'm going to have any help on this, but anyway:
I've a standard NRF52832 module that has connected to pin 5 a red LED.
If I flash the module (through JLink) with the Arduino framework, the led blinks without any problem. So there isn't a hardware issue.
Since the module is not a standard supported board, but it's a common supported processor, for using zephyr I've chose a similar board either the nrf52832_mdk or another that uses the same processor, created an overlay file to point the default LED to the correct pin and port (Port 0, pin 5), and flashed the blinky sample example.
It didn't work...
So I've checked several different based NRF52832 boards, checked that there was no pin conflicts on the DTS, only had enabled the CONFIG_GPIO=y on the prj.conf file, but nothing works. Flash it with the Arduino framework for the NRF, the link blinks.
Also flashing, for example the Zephyr BLE beacon example, works without any issue, so it seems I'm missing something crucial on the GPIO front.
I've tested with several different flags, like GPIO_OUTPUT, GPIO_OUTPUT_HIGH and so on, but nothing works.
So... any ideas of what I'm doing wrong, so that this simple GPIO is failing?