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USB: remove remaining usages of hcd->state from usbcore and fix regression

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This patch (as1467) removes the last usages of hcd->state from
usbcore.  We no longer check to see if an interrupt handler finds that
a controller has died; instead we rely on host controller drivers to
make an explicit call to usb_hc_died().

This fixes a regression introduced by commit
9b37596a2e (USB: move usbcore away from
hcd->state).  It used to be that when a controller shared an IRQ with
another device and an interrupt arrived while hcd->state was set to
HC_STATE_HALT, the interrupt handler would be skipped.  The commit
removed that test; as a result the current code doesn't skip calling
the handler and ends up believing the controller has died, even though
it's only temporarily stopped.  The solution is to ignore HC_STATE_HALT
following the handler's return.

As a consequence of this change, several of the host controller
drivers need to be modified.  They can no longer implicitly rely on
usbcore realizing that a controller has died because of hcd->state.
The patch adds calls to usb_hc_died() in the appropriate places.

The patch also changes a few of the interrupt handlers.  They don't
expect to be called when hcd->state is equal to HC_STATE_HALT, even if
the controller is still alive.  Early returns were added to avoid any
confusion.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Manuel Lauss <manuel.lauss@googlemail.com>
CC: Rodolfo Giometti <giometti@linux.it>
CC: Olav Kongas <ok@artecdesign.ee>
CC: <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Alan Stern
2011-05-17 17:27:12 -04:00
committed by Greg Kroah-Hartman
parent d23894402b
commit 69fff59de4
6 changed files with 19 additions and 9 deletions
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5
drivers/usb/core/hcd.c
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@ -986,7 +986,7 @@ static int register_root_hub(struct usb_hcd *hcd)
spin_unlock_irq (&hcd_root_hub_lock);
/* Did the HC die before the root hub was registered? */
if (HCD_DEAD(hcd) || hcd->state == HC_STATE_HALT)
if (HCD_DEAD(hcd))
usb_hc_died (hcd); /* This time clean up */
}
@ -2128,9 +2128,6 @@ irqreturn_t usb_hcd_irq (int irq, void *__hcd)
set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
if (hcd->shared_hcd)
set_bit(HCD_FLAG_SAW_IRQ, &hcd->shared_hcd->flags);
if (unlikely(hcd->state == HC_STATE_HALT))
usb_hc_died(hcd);
rc = IRQ_HANDLED;
}