usb: dwc2: host: If using uframe scheduler, end splits better
authorDouglas Anderson <dianders@chromium.org>
Fri, 29 Jan 2016 02:20:13 +0000 (18:20 -0800)
committerFelipe Balbi <balbi@kernel.org>
Fri, 4 Mar 2016 13:14:45 +0000 (15:14 +0200)
commit1479cb698ac07d5dc4cc2b7de3588d38484267e9
tree428c96aed59209f54afc73454b7b126627bfa67c
parent9f9f09b048f5fdfded26149defd61b737b314ba0
usb: dwc2: host: If using uframe scheduler, end splits better

The microframe scheduler figured out exactly how many transfers we need
for a split transaction.  Let's use this knowledge to know when to end
things.

Without this I found that certain devices would just keep responding
with tons of NYET resonses on their INT_IN endpoint.  These would just
keep going and going and eventually we'd decide to terminate the
transfer (because the whole frame changed), but by that time the
scheduler would decide that we "missed" the start of the next transfer.
I can also imagine that if we blow past the end of our scheduled time we
may mess up other things that were scheduled to happen.

No known test cases are improved by this patch except that the scheduler
code doesn't yell about MISSES constantly anymore.

Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
drivers/usb/dwc2/hcd_intr.c