Standby - Suspend to RAM (MNT Reform)

MNT Reform
33

I’m now testing modified suspend script which I plan to make a suspend target unit (to utilize systemd based suspend).
The script is below, I have tested it successfully during the day, and left overnight - which also woke up ok. It draws suspiciously big power during sleep though - 240mA in active state and 100mA in suspend (so about 2.5W). I’d expect it to be lower.

If I try to poweroff aux (mpcie, by PWR3 command) it does not affect power draw (actually makes it slightly bigger?!) but it also makes system a bit unstable - eg. system lockup when doing lspci.

Either way, there could be some win by suspending nvme perhaps (which could be done via sysfs nodes) but major win should be by clocking down various clocks (eg memory, bus, maybe shutting off some spi/i2c perephery?). Any quick hints?
The modified script:

$ cat standby 
#!/bin/bash

if [ "$EUID" -ne 0 ]
  then echo "reform-standby has to be run as root / using sudo."
  exit
fi

set_wakes() {
	# configure UARTs as wakeup sources
	echo enabled > /sys/devices/platform/soc@0/30800000.bus/30860000.serial/tty/ttymxc0/power/wakeup
	echo enabled > /sys/devices/platform/soc@0/30800000.bus/30890000.serial/tty/ttymxc1/power/wakeup
	echo enabled > /sys/devices/platform/soc@0/30800000.bus/30880000.serial/tty/ttymxc2/power/wakeup
}
radio_off() {
	# remove PCI device
	echo 1 > /sys/class/pci_bus/0000:01/device/remove
	# turn off the power on the mpcie
	#echo -en "\0PWR3" > /dev/hidraw0
	#sleep 1
}
radio_on() {
	# turn on the power on the mpcie
	#echo -en "\0PWR4" > /dev/hidraw0
	#sleep 1
	echo 1 > /sys/class/pci_bus/0000:00/rescan
	sleep 1
}
bklite_off() {
	echo -en "\0LITE0" > /dev/hidraw0
}
bklite_on() {
	echo -en "\0LITE6" > /dev/hidraw0
}

# Countdown for manual run
if [[ -z "$1" ]]; then
	echo Entering standby in 3...
	sleep 1
	echo 2...
	sleep 1
	echo 1...
	sleep 1
fi

# Either manual or suspending
if [[ -z "$1" || $1 = "suspend" ]]; then
	set_wakes
	radio_off
	bklite_off
fi

# Go sleeping for manual run
if [[ -z "$1" ]]; then
	sync
	echo mem >/sys/power/state
	sleep 1
fi

# Either manual or resuming
if [[ -z "$1" || $1 = "resume" ]]; then
	bklite_on
	radio_on
fi
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