USB: EHCI: fix timer bug affecting port resume
This patch (as1652) fixes a long-standing bug in ehci-hcd. The driver relies on status polls to know when to stop port-resume signalling. It uses the root-hub status timer to schedule these status polls. But when the driver for the root hub is resumed, the timer is rescheduled to go off immediately -- before the port is ready. When this happens the timer does not get re-enabled, which prevents the port resume from finishing until some other event occurs. The symptom is that when a new device is plugged in, it doesn't get recognized or enumerated until lsusb is run or something else happens. The solution is to re-enable the root-hub status timer after every status poll while a port resume is in progress. This bug hasn't surfaced before now because we never used to try to suspend the root hub in the middle of a port resume (except by coincidence). Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-and-tested-by: Norbert Preining <preining@logic.at> Tested-by: Ming Lei <ming.lei@canonical.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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