Tell the kernel to discard USB requests when they time out.

Tell the kernel to discard USB requests when they time out.

This patch adds a call to USBDEVFS_DISCARDURB when we time out a USB
transfer. This causes the host controller to stop polling the device for
data and means that a later transfer will receive the next bytes that
are sent from the device. Otherwise those bytes will be claimed by the
cancelled transfer and discarded.

BUG=640725
Review-Url: https://codereview.chromium.org/2274343002
Cr-Commit-Position: refs/heads/master@{#414635}
(cherry picked from commit 6f91bd7e250f649c06e1059033943d56dbf0a79f)

Committed: https://chromium.googlesource.com/chromium/src/+/6bc5ad0f6a48a2a136e5fe2510d83de6df8258ef

[Reilly Grant (use Gerrit), 2016-09-02 19:48:53]

Description was changed from

==========
Tell the kernel to discard USB requests when they time out.

This patch adds a call to USBDEVFS_DISCARDURB when we time out a USB
transfer. This causes the host controller to stop polling the device for
data and means that a later transfer will receive the next bytes that
are sent from the device. Otherwise those bytes will be claimed by the
cancelled transfer and discarded.

BUG=640725

Review-Url: https://codereview.chromium.org/2274343002
Cr-Commit-Position: refs/heads/master@{#414635}
(cherry picked from commit 6f91bd7e250f649c06e1059033943d56dbf0a79f)
==========

to

==========
Tell the kernel to discard USB requests when they time out.

This patch adds a call to USBDEVFS_DISCARDURB when we time out a USB
transfer. This causes the host controller to stop polling the device for
data and means that a later transfer will receive the next bytes that
are sent from the device. Otherwise those bytes will be claimed by the
cancelled transfer and discarded.

BUG=640725

Review-Url: https://codereview.chromium.org/2274343002
Cr-Commit-Position: refs/heads/master@{#414635}
(cherry picked from commit 6f91bd7e250f649c06e1059033943d56dbf0a79f)

Committed:
https://chromium.googlesource.com/chromium/src/+/6bc5ad0f6a48a2a136e5fe2510d8...
==========

[Reilly Grant (use Gerrit), 2016-09-02 19:48:54]

Committed patchset #1 (id:1) manually as
6bc5ad0f6a48a2a136e5fe2510d83de6df8258ef.