I am looking for a way to hook into the charge event, that is started if the device is turned off. You know that one, that starts an animation of a charging battery.
I am having a rooted phone and want to start the phone if the charger is connected.
Fist of all I need to know what part of the system this is? The bootloader?
That is definitely outside of the domain of Android, definitely not the bootloader, rather an internal of the SoC on the circuitary board, which gets triggered and displays an animating battery charging whilst switched off.
That is outside the scope of Android.