USB: fix ehci unlink regressions
The recent EHCI driver update to split the IAA watchdog timer out from
the other timers made several things work better, but not everything;
and it created a couple new issues in bugzilla. Ergo this patch:
- Handle a should-be-rare SMP race between the watchdog firing
and (very late) IAA interrupts;
- Remove a shouldn't-have-been-added WARN_ON() test;
- Guard against one observed OOPS;
- If this watchdog fires during clean HC shutdown, it should act
as a NOP instead of interfering with the shutdown sequence;
- Guard against silicon errata hypothesized by some vendors:
* IAA status latch broken, but IAAD cleared OK;
* IAAD wasn't cleared when IAA status got reported;
The WARN_ON is in bugzilla as 10168; the OOPS as 10078; these are
both regressions.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Tested-by: Gordon Farquharson <gordonfarquharson@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
1 file changed