We are using the SAMA5D2 on a custom board. Our OS build is based on buildroot. When we shutdown the board with 'poweroff' or 'halt', the ACT8945A never fully shuts off the regulators. Instead the board will idle for about 5 seconds and then reboot.
I suspect the ACT8945A MSTROFF bit (register 0x01, bit 5) is never written via i2c. The MSTROFF bit tells all regulators to turnoff. Our linux build does includes the ACT8945A drivers. Recently I built the drivers as removable modules and and tried the following:
i2cset 0 0x5b 0x01 0x20
As expected all regulators immediately powered down.
Poweroff, halt, and shutdown work as expected on the SAMA5D2 Xplained board; I compared configs but so far nothing doing.
My assumption is the device driver should handle this. Any ideas?