Fully working armada-385-synology-ds216j.dts: green and amber HDD LEDs, LAN LED, LED brightness, chassis buttons, and everything else (no replies)

Hello everyone!

I'd like to share some good results with the community.

I've successfully adapted the Device Tree for the Synology DS216j NAS. All hardware is working perfectly, including:

1. Individual access to each drive's LED via GPIO. Both green and amber LEDs are available.
2. Customizable LAN LED behavior. Now it can blink like in the stock DSM OS.
3. Adjustable brightness for all LEDs.
4. Power and Reset chassis buttons are accessible via the UART1 bus.

I believe the issues that prevent these features from working on other Synology NAS devices with similar architectures can be fixed in a similar way. Just as I fixed them in this Device Tree.

This is the main repository with the Device Tree: https://github.com/ae9o/armada-385-synology-ds216j.dts

I've also prepared several additional services that allow to fully reproduce the behavior of the stock DSM OS after installing Debian:

1. This service turns on/off the LEDs based on the hd-idle service's actions: https://github.com/ae9o/diskstation-ledd
2. This is handler for chassis button presses: https://github.com/ae9o/diskstation-keyd

Hope this will be useful to someone.