I am working with the Apalis iMX6Q running TorizonCore. I have been experimenting with the low power modes, and have run into problems with the suspend state.
When I put the module into standby, I am able to bring it back out in its original state using MXM3 pin 37, as described in this tutorial:
However, I would like to use the suspend mode to reduce power consumption further. When I put the module into the suspend state, I am able to bring it out again by driving pin 37 low, but when I do this the module does not seem to restart all of the peripherals that were originally running: the ethernet port does not get re-enabled, and the shell does not re-appear on the LCD screen I have attached.
It also seems possible that the peripherals do power back up but all the processes the CPU had been running never get re-launched, because the power consumption after wakeup is considerably larger than the power consumption prior to entering the suspend mode.
Does anybody have any insight into what is going on here? Is there a way that I can customize which peripherals get powered on/off when suspending and resuming? How are these processes configured? If this is not a power on/off issue and the problem is with Linux, is systemd responsible for restarting processes after exiting suspend mode?