msm: 8974: MHL-USB handshake API implementation

This change adds the implementation of mhl discovery
detection procedure, USB hand-off function. Three APIs
are exposed from MHL driver to USB driver: for
register/unregistering callbacks from USB and triggering
device discovery detection in MHL hardware. By default, all
the USB interrupts are directed to the USB hardware which is
detected by USB driver and at appropriate points the USB
driver triggers the MHL device discovery and uses the results
to either hand control to MHL driver or continue with it's own
detection mechanism.

Change-Id: Ic1e22bc4c446de209f2e72d5dda8b823bfd398c8
Signed-off-by: Manoj Rao <manojraj@codeaurora.org>
2 files changed