I have the same question, but sadly no real answer.
I have an Ainol Novo 7 Paladin tablet (android 4.0.3) which supports USB host mode via its mini USB connector. I am using a standard OTG adaper that I bought for a few € on ebay. This is all working great, but sadly I need the thing to run from the USB power or charge the battery with the OTG active.
From what I've read there are two possible solutions to this problem - a hardware one (as seen here) that is less commonly supported (doesn't work on most devices) and a software solution that should work anywhere. So I am trying to find a way to get a working software solution.
Now apparently you can change the mode by doing this:
Code:
echo host > /sys/devices/platform/musb-jz47xx.0/musb-hdrc/mode
On other devices (with standard ARM architecture, and not MIPS) it is usually without the musb-jz47xx.0 part.
Now ok this works for a standard usb host mode - at least it doesn't give out any errors. Now using otg instead of host should enable charge and host mode. Sadly it doesn't. It throws out Segmentation Fault and throws me out of root shell with exit status 139. Now using unsupported mode usually just gives out exit status 1 and that is it. So there must be something with the otg command. But I have no idea what is wrong.
I also found out that plugging and unplugging my USB otg cable (with an Y splitter - one side connected to a charger and the other one with an inserted USB device) a few times the tablet actually switches to host mode while showing that it is charging. Sadly the battery percentage then stays the same and the whole thing just shuts down after a few hours (when you start it again you find out that the battery is empty) - although it lasts longer than normally. So something strange is going on here.
Any ideas?
