10 files changed, 132 insertions, 25 deletions

diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c
index 5131d88e8c5b..29b5b2a6e183 100644
--- a/drivers/usb/core/hcd-pci.c
+++ b/drivers/usb/core/hcd-pci.c
@@ -219,6 +219,7 @@ int usb_hcd_pci_suspend (struct pci_dev *dev, pm_message_t message)
                         goto done;
                 }
         }
+        synchronize_irq(dev->irq);
 
         /* FIXME until the generic PM interfaces change a lot more, this
          * can't use PCI D1 and D2 states.  For example, the confusion
@@ -392,7 +393,7 @@ int usb_hcd_pci_resume (struct pci_dev *dev)
 
         dev->dev.power.power_state = PMSG_ON;
 
-        hcd->saw_irq = 0;
+        clear_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
 
         if (hcd->driver->resume) {
                 retval = hcd->driver->resume(hcd);
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 5e5f65a475ab..da24c31ee00d 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -1315,11 +1315,12 @@ static int hcd_unlink_urb (struct urb *urb, int status)
          * finish unlinking the initial failed usb_set_address()
          * or device descriptor fetch.
          */
-        if (!hcd->saw_irq && hcd->self.root_hub != urb->dev) {
+        if (!test_bit(HCD_FLAG_SAW_IRQ, &hcd->flags)
+            && hcd->self.root_hub != urb->dev) {
                 dev_warn (hcd->self.controller, "Unlink after no-IRQ?  "
                         "Controller is probably using the wrong IRQ."
                         "\n");
-                hcd->saw_irq = 1;
+                set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
         }
 
         urb->status = status;
@@ -1649,13 +1650,15 @@ irqreturn_t usb_hcd_irq (int irq, void *__hcd, struct pt_regs * r)
         struct usb_hcd          *hcd = __hcd;
         int                     start = hcd->state;
 
-        if (start == HC_STATE_HALT)
+        if (unlikely(start == HC_STATE_HALT ||
+            !test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)))
                 return IRQ_NONE;
         if (hcd->driver->irq (hcd, r) == IRQ_NONE)
                 return IRQ_NONE;
 
-        hcd->saw_irq = 1;
-        if (hcd->state == HC_STATE_HALT)
+        set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
+
+        if (unlikely(hcd->state == HC_STATE_HALT))
                 usb_hc_died (hcd);
         return IRQ_HANDLED;
 }
@@ -1768,6 +1771,8 @@ int usb_add_hcd(struct usb_hcd *hcd,
 
         dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
 
+        set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
+
         /* till now HC has been in an indeterminate state ... */
         if (hcd->driver->reset && (retval = hcd->driver->reset(hcd)) < 0) {
                 dev_err(hcd->self.controller, "can't reset\n");
diff --git a/drivers/usb/core/hcd.h b/drivers/usb/core/hcd.h
index 24a62a2ff86d..c8a1b350e2cf 100644
--- a/drivers/usb/core/hcd.h
+++ b/drivers/usb/core/hcd.h
@@ -72,7 +72,12 @@ struct usb_hcd {	/* usb_bus.hcpriv points to this */
          * hardware info/state
          */
         const struct hc_driver  *driver;        /* hw-specific hooks */
-        unsigned                saw_irq : 1;
+
+        /* Flags that need to be manipulated atomically */
+        unsigned long           flags;
+#define HCD_FLAG_HW_ACCESSIBLE  0x00000001
+#define HCD_FLAG_SAW_IRQ        0x00000002
+
         unsigned                can_wakeup:1;   /* hw supports wakeup? */
         unsigned                remote_wakeup:1;/* sw should use wakeup? */
         unsigned                rh_registered:1;/* is root hub registered? */
diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
index 441c26064b44..14fff5714c1e 100644
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -228,14 +228,36 @@ static int ehci_pci_reset(struct usb_hcd *hcd)
 static int ehci_pci_suspend(struct usb_hcd *hcd, pm_message_t message)
 {
         struct ehci_hcd         *ehci = hcd_to_ehci(hcd);
+        unsigned long           flags;
+        int                     rc = 0;
 
         if (time_before(jiffies, ehci->next_statechange))
                 msleep(10);
 
+        /* Root hub was already suspended. Disable irq emission and
+         * mark HW unaccessible, bail out if RH has been resumed. Use
+         * the spinlock to properly synchronize with possible pending
+         * RH suspend or resume activity.
+         *
+         * This is still racy as hcd->state is manipulated outside of
+         * any locks =P But that will be a different fix.
+         */
+        spin_lock_irqsave (&ehci->lock, flags);
+        if (hcd->state != HC_STATE_SUSPENDED) {
+                rc = -EINVAL;
+                goto bail;
+        }
+        writel (0, &ehci->regs->intr_enable);
+        (void)readl(&ehci->regs->intr_enable);
+
+        clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
+ bail:
+        spin_unlock_irqrestore (&ehci->lock, flags);
+
         // could save FLADJ in case of Vaux power loss
         // ... we'd only use it to handle clock skew
 
-        return 0;
+        return rc;
 }
 
 static int ehci_pci_resume(struct usb_hcd *hcd)
@@ -251,6 +273,9 @@ static int ehci_pci_resume(struct usb_hcd *hcd)
         if (time_before(jiffies, ehci->next_statechange))
                 msleep(100);
 
+        /* Mark hardware accessible again as we are out of D3 state by now */
+        set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
+
         /* If CF is clear, we lost PCI Vaux power and need to restart.  */
         if (readl(&ehci->regs->configured_flag) != FLAG_CF)
                 goto restart;
diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c
index 5bb872c3496d..bf03ec0d8ee2 100644
--- a/drivers/usb/host/ehci-q.c
+++ b/drivers/usb/host/ehci-q.c
@@ -912,6 +912,7 @@ submit_async (
         int                     epnum;
         unsigned long           flags;
         struct ehci_qh          *qh = NULL;
+        int                     rc = 0;
 
         qtd = list_entry (qtd_list->next, struct ehci_qtd, qtd_list);
         epnum = ep->desc.bEndpointAddress;
@@ -926,21 +927,28 @@ submit_async (
 #endif
 
         spin_lock_irqsave (&ehci->lock, flags);
+        if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE,
+                               &ehci_to_hcd(ehci)->flags))) {
+                rc = -ESHUTDOWN;
+                goto done;
+        }
+
         qh = qh_append_tds (ehci, urb, qtd_list, epnum, &ep->hcpriv);
+        if (unlikely(qh == NULL)) {
+                rc = -ENOMEM;
+                goto done;
+        }
 
         /* Control/bulk operations through TTs don't need scheduling,
          * the HC and TT handle it when the TT has a buffer ready.
          */
-        if (likely (qh != NULL)) {
-                if (likely (qh->qh_state == QH_STATE_IDLE))
-                        qh_link_async (ehci, qh_get (qh));
-        }
+        if (likely (qh->qh_state == QH_STATE_IDLE))
+                qh_link_async (ehci, qh_get (qh));
+ done:
         spin_unlock_irqrestore (&ehci->lock, flags);
-        if (unlikely (qh == NULL)) {
+        if (unlikely (qh == NULL))
                 qtd_list_free (ehci, urb, qtd_list);
-                return -ENOMEM;
-        }
-        return 0;
+        return rc;
 }
 
 /*-------------------------------------------------------------------------*/
diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c
index f0c8aa1ccd5d..57e77374d228 100644
--- a/drivers/usb/host/ehci-sched.c
+++ b/drivers/usb/host/ehci-sched.c
@@ -602,6 +602,12 @@ static int intr_submit (
 
         spin_lock_irqsave (&ehci->lock, flags);
 
+        if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE,
+                               &ehci_to_hcd(ehci)->flags))) {
+                status = -ESHUTDOWN;
+                goto done;
+        }
+
         /* get qh and force any scheduling errors */
         INIT_LIST_HEAD (&empty);
         qh = qh_append_tds (ehci, urb, &empty, epnum, &ep->hcpriv);
@@ -1456,7 +1462,11 @@ static int itd_submit (struct ehci_hcd *ehci, struct urb *urb,
 
         /* schedule ... need to lock */
         spin_lock_irqsave (&ehci->lock, flags);
-        status = iso_stream_schedule (ehci, urb, stream);
+        if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE,
+                               &ehci_to_hcd(ehci)->flags)))
+                status = -ESHUTDOWN;
+        else
+                status = iso_stream_schedule (ehci, urb, stream);
         if (likely (status == 0))
                 itd_link_urb (ehci, urb, ehci->periodic_size << 3, stream);
         spin_unlock_irqrestore (&ehci->lock, flags);
@@ -1815,7 +1825,11 @@ static int sitd_submit (struct ehci_hcd *ehci, struct urb *urb,
 
         /* schedule ... need to lock */
         spin_lock_irqsave (&ehci->lock, flags);
-        status = iso_stream_schedule (ehci, urb, stream);
+        if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE,
+                               &ehci_to_hcd(ehci)->flags)))
+                status = -ESHUTDOWN;
+        else
+                status = iso_stream_schedule (ehci, urb, stream);
         if (status == 0)
                 sitd_link_urb (ehci, urb, ehci->periodic_size << 3, stream);
         spin_unlock_irqrestore (&ehci->lock, flags);
diff --git a/drivers/usb/host/ohci-hcd.c b/drivers/usb/host/ohci-hcd.c
index 5c0c6c8a7a82..bf1d9abc07ac 100644
--- a/drivers/usb/host/ohci-hcd.c
+++ b/drivers/usb/host/ohci-hcd.c
@@ -115,7 +115,7 @@
 
 /*-------------------------------------------------------------------------*/
 
-// #define OHCI_VERBOSE_DEBUG   /* not always helpful */
+#undef OHCI_VERBOSE_DEBUG       /* not always helpful */
 
 /* For initializing controller (mask in an HCFS mode too) */
 #define OHCI_CONTROL_INIT       OHCI_CTRL_CBSR
@@ -253,6 +253,10 @@ static int ohci_urb_enqueue (
         spin_lock_irqsave (&ohci->lock, flags);
 
         /* don't submit to a dead HC */
+        if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)) {
+                retval = -ENODEV;
+                goto fail;
+        }
         if (!HC_IS_RUNNING(hcd->state)) {
                 retval = -ENODEV;
                 goto fail;
diff --git a/drivers/usb/host/ohci-hub.c b/drivers/usb/host/ohci-hub.c
index e01e77bc324b..72e3b12a1926 100644
--- a/drivers/usb/host/ohci-hub.c
+++ b/drivers/usb/host/ohci-hub.c
@@ -53,6 +53,11 @@ static int ohci_bus_suspend (struct usb_hcd *hcd)
 
         spin_lock_irqsave (&ohci->lock, flags);
 
+        if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags))) {
+                spin_unlock_irqrestore (&ohci->lock, flags);
+                return -ESHUTDOWN;
+        }
+
         ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
         switch (ohci->hc_control & OHCI_CTRL_HCFS) {
         case OHCI_USB_RESUME:
@@ -140,11 +145,19 @@ static int ohci_bus_resume (struct usb_hcd *hcd)
         struct ohci_hcd         *ohci = hcd_to_ohci (hcd);
         u32                     temp, enables;
         int                     status = -EINPROGRESS;
+        unsigned long           flags;
 
         if (time_before (jiffies, ohci->next_statechange))
                 msleep(5);
 
-        spin_lock_irq (&ohci->lock);
+        spin_lock_irqsave (&ohci->lock, flags);
+
+        if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags))) {
+                spin_unlock_irqrestore (&ohci->lock, flags);
+                return -ESHUTDOWN;
+        }
+
+
         ohci->hc_control = ohci_readl (ohci, &ohci->regs->control);
 
         if (ohci->hc_control & (OHCI_CTRL_IR | OHCI_SCHED_ENABLES)) {
@@ -179,7 +192,7 @@ static int ohci_bus_resume (struct usb_hcd *hcd)
                 ohci_dbg (ohci, "lost power\n");
                 status = -EBUSY;
         }
-        spin_unlock_irq (&ohci->lock);
+        spin_unlock_irqrestore (&ohci->lock, flags);
         if (status == -EBUSY) {
                 (void) ohci_init (ohci);
                 return ohci_restart (ohci);
@@ -297,8 +310,8 @@ ohci_hub_status_data (struct usb_hcd *hcd, char *buf)
         /* handle autosuspended root:  finish resuming before
          * letting khubd or root hub timer see state changes.
          */
-        if ((ohci->hc_control & OHCI_CTRL_HCFS) != OHCI_USB_OPER
-                        || !HC_IS_RUNNING(hcd->state)) {
+        if (unlikely((ohci->hc_control & OHCI_CTRL_HCFS) != OHCI_USB_OPER
+                     || !HC_IS_RUNNING(hcd->state))) {
                 can_suspend = 0;
                 goto done;
         }
@@ -508,6 +521,9 @@ static int ohci_hub_control (
         u32             temp;
         int             retval = 0;
 
+        if (unlikely(!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags)))
+                return -ESHUTDOWN;
+
         switch (typeReq) {
         case ClearHubFeature:
                 switch (wValue) {
diff --git a/drivers/usb/host/ohci-pci.c b/drivers/usb/host/ohci-pci.c
index 5f22e6590cd1..1b09dde068e1 100644
--- a/drivers/usb/host/ohci-pci.c
+++ b/drivers/usb/host/ohci-pci.c
@@ -105,13 +105,36 @@ ohci_pci_start (struct usb_hcd *hcd)
 
 static int ohci_pci_suspend (struct usb_hcd *hcd, pm_message_t message)
 {
-        /* root hub was already suspended */
-        return 0;
+        struct ohci_hcd *ohci = hcd_to_ohci (hcd);
+        unsigned long   flags;
+        int             rc = 0;
+
+        /* Root hub was already suspended. Disable irq emission and
+         * mark HW unaccessible, bail out if RH has been resumed. Use
+         * the spinlock to properly synchronize with possible pending
+         * RH suspend or resume activity.
+         *
+         * This is still racy as hcd->state is manipulated outside of
+         * any locks =P But that will be a different fix.
+         */
+        spin_lock_irqsave (&ohci->lock, flags);
+        if (hcd->state != HC_STATE_SUSPENDED) {
+                rc = -EINVAL;
+                goto bail;
+        }
+        ohci_writel(ohci, OHCI_INTR_MIE, &ohci->regs->intrdisable);
+        (void)ohci_readl(ohci, &ohci->regs->intrdisable);
+        clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
+ bail:
+        spin_unlock_irqrestore (&ohci->lock, flags);
+
+        return rc;
 }
 
 
 static int ohci_pci_resume (struct usb_hcd *hcd)
 {
+        set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
         usb_hcd_resume_root_hub(hcd);
         return 0;
 }
diff --git a/drivers/usb/host/uhci-hcd.c b/drivers/usb/host/uhci-hcd.c
index d33ce3982a5f..ed550132db0b 100644
--- a/drivers/usb/host/uhci-hcd.c
+++ b/drivers/usb/host/uhci-hcd.c
@@ -717,6 +717,7 @@ static int uhci_suspend(struct usb_hcd *hcd, pm_message_t message)
          * at the source, so we must turn off PIRQ.
          */
         pci_write_config_word(to_pci_dev(uhci_dev(uhci)), USBLEGSUP, 0);
+        clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
         uhci->hc_inaccessible = 1;
         hcd->poll_rh = 0;
 
@@ -733,6 +734,11 @@ static int uhci_resume(struct usb_hcd *hcd)
 
         dev_dbg(uhci_dev(uhci), "%s\n", __FUNCTION__);
 
+        /* We aren't in D3 state anymore, we do that even if dead as I
+         * really don't want to keep a stale HCD_FLAG_HW_ACCESSIBLE=0
+         */
+        set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
+
         if (uhci->rh_state == UHCI_RH_RESET)    /* Dead */
                 return 0;
         spin_lock_irq(&uhci->lock);