usb: hub: Clear Port Reset Change during init/resume
authorJulius Werner <jwerner@chromium.org>
Wed, 16 Oct 2013 00:45:00 +0000 (17:45 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 16 Oct 2013 20:44:54 +0000 (13:44 -0700)
commite92aee330837e4911553761490a8fb843f2053a6
tree64e39faa5f0d1ad538659663eee49535397403ac
parent06793f2d0cf9daabeeb5b024d4bf7082dcc71505
usb: hub: Clear Port Reset Change during init/resume

This patch adds the Port Reset Change flag to the set of bits that are
preemptively cleared on init/resume of a hub. In theory this bit should
never be set unexpectedly... in practice it can still happen if BIOS,
SMM or ACPI code plays around with USB devices without cleaning up
correctly. This is especially dangerous for XHCI root hubs, which don't
generate any more Port Status Change Events until all change bits are
cleared, so this is a good precaution to have (similar to how it's
already done for the Warm Port Reset Change flag).

Signed-off-by: Julius Werner <jwerner@chromium.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/core/hub.c