when the USB host controller is the parent of the connector,
usually type-B, sometimes don't need the graph, so we should
check whether it's parent registers usb-role-switch or not
firstly, and get it if exists.
Suggested-by: NHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: NChunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1567070558-29417-9-git-send-email-chunfeng.yun@mediatek.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>