Nexus 7 host mode charging
Nexus 7 in USB host mode, operating a slave device and being charged at the same time? Here is an installable kernel image that makes it possible.
This Nexus 7 boot image contains a CM10 based kernel including the USB host mode charging patch. To flash the image run:
$ fastboot flash boot boot-cm10-grouper-otg-power.img
Edit: UPDATE AVAILABLE: HERE
You need CM10 for Nexus 7 installed prior to installing this kernel. You should have CWM installed, for when you want to revert. And you will need a USB Y-cable, just like you do for the Galaxy Nexus.
Edit: This is the patch. When a host mode adapter has been recognized, charging of USB slave devices (OTG mode) will NOT be activated and instead vbus will be raised in order to accept power from an external source.
Edit 2: An additional patch is needed for the Nexus 7 to not just operate on external power and have it's battery charged - but for it to also "become aware" of the fact that it's battery is being charged, while in host mode. As a result, Settings -> Battery should show "XX% Charging (USB)" - or just "100% Full". A new Nexus 7 boot image containing both patches.
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