How to make Android device boot when power is plugged in?

Question

I need to use this for a Samsung Tablet.

Usually if the device is switched-off and the USB cable is being connected the display will wake up for some seconds showing an animated battery. Instead I want to let it boot.

I suspect this is close to the metal. Where do I have to make a modification? In the kernel, in the Android platform, or is this hidden in some proprietary code of the manufacturer?

Answer 1

A member on XDA has posted a solution for this which seems to work on some Samsung devices.

The idea is to replace the script for the battery icon (which will appear of course as soon as the device is plugged in) with a custom script that will boot the phone. To make this work locate /system/bin/playlpm. Rename the old playlpm to playlpm.bak and replace it with the following script:

#!/system/bin/sh
/system/bin/reboot

For more information read the thread on XDA

Answer 2

I have a rooted Samsung S4 mini. The following steps worked for me:

1. mount -o remount,rw /system
2. mv /system/bin/lpm /system/bin/lpm.orig

3. create /system/bin/lpm as follows:

   #!/system/bin/sh
   /system/bin/lpm.orig &
   while [ true ]; do
     sleep 1
     ps | grep lpm.orig && sleep 3 && /system/bin/reboot
   done
   

4. chown root.shell /system/bin/lpm