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
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>

drivers/usb/core/hcd.c

@@ -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;
 	}
 

drivers/usb/host/ehci-hcd.c

@@ -777,8 +777,9 @@ static irqreturn_t ehci_irq (struct usb_hcd *hcd)
 		goto dead;
 	}
 
+	/* Shared IRQ? */
 	masked_status = status & INTR_MASK;
-	if (!masked_status) {		/* irq sharing? */
+	if (!masked_status || unlikely(hcd->state == HC_STATE_HALT)) {
 		spin_unlock(&ehci->lock);
 		return IRQ_NONE;
 	}
@@ -873,6 +874,7 @@ static irqreturn_t ehci_irq (struct usb_hcd *hcd)
 dead:
 		ehci_reset(ehci);
 		ehci_writel(ehci, 0, &ehci->regs->configured_flag);
+		usb_hc_died(hcd);
 		/* generic layer kills/unlinks all urbs, then
 		 * uses ehci_stop to clean up the rest
 		 */

drivers/usb/host/ehci-sched.c

@@ -471,8 +471,10 @@ static int enable_periodic (struct ehci_hcd *ehci)
 	 */
 	status = handshake_on_error_set_halt(ehci, &ehci->regs->status,
 					     STS_PSS, 0, 9 * 125);
-	if (status)
+	if (status) {
+		usb_hc_died(ehci_to_hcd(ehci));
 		return status;
+	}
 
 	cmd = ehci_readl(ehci, &ehci->regs->command) | CMD_PSE;
 	ehci_writel(ehci, cmd, &ehci->regs->command);
@@ -510,8 +512,10 @@ static int disable_periodic (struct ehci_hcd *ehci)
 	 */
 	status = handshake_on_error_set_halt(ehci, &ehci->regs->status,
 					     STS_PSS, STS_PSS, 9 * 125);
-	if (status)
+	if (status) {
+		usb_hc_died(ehci_to_hcd(ehci));
 		return status;
+	}
 
 	cmd = ehci_readl(ehci, &ehci->regs->command) & ~CMD_PSE;
 	ehci_writel(ehci, cmd, &ehci->regs->command);

drivers/usb/host/isp116x-hcd.c

@@ -612,6 +612,7 @@ static irqreturn_t isp116x_irq(struct usb_hcd *hcd)
 			/* IRQ's are off, we do no DMA,
 			   perfectly ready to die ... */
 			hcd->state = HC_STATE_HALT;
+			usb_hc_died(hcd);
 			ret = IRQ_HANDLED;
 			goto done;
 		}

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);

drivers/usb/host/oxu210hp-hcd.c

@@ -1884,6 +1884,7 @@ static int enable_periodic(struct oxu_hcd *oxu)
 	status = handshake(oxu, &oxu->regs->status, STS_PSS, 0, 9 * 125);
 	if (status != 0) {
 		oxu_to_hcd(oxu)->state = HC_STATE_HALT;
+		usb_hc_died(oxu_to_hcd(oxu));
 		return status;
 	}
 
@@ -1909,6 +1910,7 @@ static int disable_periodic(struct oxu_hcd *oxu)
 	status = handshake(oxu, &oxu->regs->status, STS_PSS, STS_PSS, 9 * 125);
 	if (status != 0) {
 		oxu_to_hcd(oxu)->state = HC_STATE_HALT;
+		usb_hc_died(oxu_to_hcd(oxu));
 		return status;
 	}
 
@@ -2449,8 +2451,9 @@ static irqreturn_t oxu210_hcd_irq(struct usb_hcd *hcd)
 		goto dead;
 	}
 
+	/* Shared IRQ? */
 	status &= INTR_MASK;
-	if (!status) {			/* irq sharing? */
+	if (!status || unlikely(hcd->state == HC_STATE_HALT)) {
 		spin_unlock(&oxu->lock);
 		return IRQ_NONE;
 	}
@@ -2516,6 +2519,7 @@ static irqreturn_t oxu210_hcd_irq(struct usb_hcd *hcd)
 dead:
 			ehci_reset(oxu);
 			writel(0, &oxu->regs->configured_flag);
+			usb_hc_died(hcd);
 			/* generic layer kills/unlinks all urbs, then
 			 * uses oxu_stop to clean up the rest
 			 */