usb: host: xhci: update event ring dequeue pointer on purpose

On some situations, the software handles TRB events slower
than adding TRBs, then xhci_handle_event can't return zero
long time, the xHC will consider the event ring is full,
and trigger "Event Ring Full" error, but in fact, the software
has already finished lots of events, just no chance to
update ERDP (event ring dequeue pointer).

In this commit, we force update ERDP if half of TRBS_PER_SEGMENT
events have handled to avoid "Event Ring Full" error.

Change-Id: I88b8dff5f7c3d6848a17c9efe564475602bf701d
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/1573836603-10871-2-git-send-email-mathias.nyman@linux.intel.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Git-commit: dc0ffbea5729a3abafa577ebfce87f18b79e294b
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Signed-off-by: Ajay Agarwal <ajaya@codeaurora.org>