BatteryManager Service

[Jose Luis s]

Hi all.

I need for one of my projects with android-x86 that my tablet works with a lot of usb devices connected and connected to power, but as most intel tablets there is only an OTG microusb connector. I've tried most of the proposed solutions from inet, even bought 4-5 otg hubs that claimed to work in a otg mode and charging simultaneously, but only get them working in Windows not in android-x86 (same EFI configuration)

Some DIY seems to point in the good direction but I didn't found the right resistor value to activate charging and otg at the same time, also in some designs a switch is needed and this is not an option for my project.

So I search for some different aproaches, from trying to use usbip from my router, no way because I don't find any alternative to usbip userland tools in android, and some similar.

The last I tried is to use some external Battery charger controller to my battery and use the otg as otg usb host. I seems to work fine but I've found that the battery gauge service reports the Battery charge status from some register not related to Battery voltage, so Android thinks that the battery is empty after some hours despite the battery is fully charge.

So I need to disconnect the external charger controller and charge again using the internal charger circuit in my tablet.

Batterystats.bin file reset (root erase) does not help at all, the tablet think that the battery is empty and even does not boot at all when android-x86 try to boot, probably due to Batterymanager service.

Of course I cannot edit or modify /sys/class/ filesystem even root to modify the uevent or other battery info file.

Also try to use dumpsys battery set to modify the values, this works in one session but the values are lost after the tablet reboot.

Can anybody help with an alternative?

A specific Android-x86 compilation without battery maybe? I've found a patch to change the sources, but I never was able to compile the whole source (don't know why) only kernel.....

I've tried to blacklist the kernel module at boot but then my tablet does not boot.

Please help