Control K3 charge LED

[ilikepaper]

The charging LED was bothering me and wanted it off, and couldn't find anything here on how to control it. So I started to probe around, found pmic binary which seems to access the power management IC which is responsible for charging the battery.
I got lucky as after I "no-battery" modded my Kindle, I managed to get the green LED on a boot (it's usually the amber one), so I used pmic to dump all power management IC data, and compared between green and amber LED states.
While trying to transition one state to the other, writing the green LED data dump when the amber LED was active, I managed to figure out some addresses that control both amber and green LED on/off, so now I can turn them on/off with a few lines.

I have no clue if these changes affect the LED state or more complicated states that result in LEDs being on/off. I wouldn't try this with a battery attached.
Green LED has precedence over amber, so you first want to turn it off:

pmic wor 0x35 23 0 0

Then you can turn off the amber LED

pmic wor 0x30 23 0 0x810203

Turning green LED on (more bit configs work here, 0x300000 and 5/7/9/B/D)

pmic wor 0x35 23 0 0xF00000

Turning amber LED on

pmic wor 0x30 23 0 0x850203

Also as somewhat related I was able to stop the screensaver without using kaffeine, by changing a few settings in powerd. Made a new script in /etc/init.d/

# cat /etc/init.d/prevent_screensaver
#!/bin/sh
# Prevent Kindle from activating screen saver
# Works by setting com.lab126.powerd properties
# Can start, stop, or restart

_FUNCTIONS=/etc/rc.d/functions
[ -f ${_FUNCTIONS} ] && . ${_FUNCTIONS}

NAME="prevent_screensaver"

case "$1" in
    start)
        msg "Starting $NAME: prevent screen saver" I
        lipc-set-prop com.lab126.powerd preventScreenSaver 1
#        lipc-set-prop com.lab126.powerd wakeUp 1
        ;;
    stop)
        msg "Stopping $NAME: allow screen saver" I
        lipc-set-prop com.lab126.powerd preventScreenSaver 0
        ;;
    restart)
        $0 stop
        sleep 1
        $0 start
        ;;
    *)
        msg "Usage: $0 {start|stop|restart}" W >&2
        exit 1
        ;;
esac

exit 0

Not sure if setting wakeUp to 1 is required, seems to work without it. Linked it in /etc/rc5.d/S99prevent_screensaver