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ade-ma / MotoGNotes

knowledge centralization for sproutwave android dev
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USB Doesn't Support Host & Charging Simultaneously #1

Open itdaniher opened 10 years ago

itdaniher commented 10 years ago

USB OTG defines a "A" mode where the slave device is unpowered and the host device can charge.

Other modes have either the phone charging but not talking to radios or the phone talking but not charging.

Fixing this (AFAIK) requires some kernel modification....

itdaniher commented 10 years ago

Light reading:

http://lxr.free-electrons.com/source/include/linux/usb/msm_hsusb.h

http://lxr.free-electrons.com/source/drivers/usb/otg/msm_otg.c?v=3.4

https://github.com/gp-b2g/gp-peak-kernel/blob/master/Documentation/usb/msm_otg.txt

itdaniher commented 10 years ago

related: https://mehrvarz.github.io/usb-host-mode-power-management-nexus7/