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

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
9b37596a2e860404503a3f2a6513db60c296bfdc (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>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c
index 8c8dc6559ac..9aa10bdf391 100644
--- a/drivers/usb/host/ohci-hcd.c
+++ b/drivers/usb/host/ohci-hcd.c
@@ -764,6 +764,7 @@ static irqreturn_t ohci_irq (struct usb_hcd *hcd)
 	if (ints == ~(u32)0) {
 		disable (ohci);
 		ohci_dbg (ohci, "device removed!\n");
+		usb_hc_died(hcd);
 		return IRQ_HANDLED;
 	}
 
@@ -771,7 +772,7 @@ static irqreturn_t ohci_irq (struct usb_hcd *hcd)
 	ints &= ohci_readl(ohci, &regs->intrenable);
 
 	/* interrupt for some other device? */
-	if (ints == 0)
+	if (ints == 0 || unlikely(hcd->state == HC_STATE_HALT))
 		return IRQ_NOTMINE;
 
 	if (ints & OHCI_INTR_UE) {
@@ -788,6 +789,7 @@ static irqreturn_t ohci_irq (struct usb_hcd *hcd)
 		} else {
 			disable (ohci);
 			ohci_err (ohci, "OHCI Unrecoverable Error, disabled\n");
+			usb_hc_died(hcd);
 		}
 
 		ohci_dump (ohci, 1);