msm: mhl_sii8334: support USB charging

Add "ext-vbus" power_supply which acts as a supplier to the USB
power_supply. When MHL is detected, it will notify USB of the
online and present states, as well as set the current limit.

Currently (no pun intended) there is no specification in MHL
about specific amperage, other than minimum required for operation,
so use 700mA for now.

Change-Id: Iab5d82b29bca66330922f1da404d3bfe5d95024f
Signed-off-by: Jack Pham <jackp@codeaurora.org>
1 file changed