[PATCH] USB: EHCI updates

This fixes some bugs in EHCI suspend/resume that joined us over the past
few releases (as usbcore, PCI, pmcore, and other components evolved):

  - Removes suspend and resume recursion from the EHCI driver, getting
    rid of the USB_SUSPEND special casing.

  - Updates the wakeup mechanism to work again; there's a newish usbcore
    call it needs to use.

  - Provide simpler tests for "do we need to restart from scratch", to
    address another case where PCI Vaux was lost.  (In this case it was
    restoring a swsusp snapshot, but there could be others.)

Un-exports a symbol that was temporarily exported.

A notable change from previous version is that this doesn't move
the spinlock init, so there's still a resume/reinit path bug.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 8407279..f78bd12 100644 (file)
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1669,7 +1669,6 @@ int usb_suspend_device(struct usb_device *udev)
        return 0;
 #endif
 }
-EXPORT_SYMBOL_GPL(usb_suspend_device);
 
 /*
  * If the USB "suspend" state is in use (rather than "global suspend"),

diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index af3c05e..f15144e 100644 (file)
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -636,9 +636,8 @@ static irqreturn_t ehci_irq (struct usb_hcd *hcd, struct pt_regs *regs)
                         * stop that signaling.
                         */
                        ehci->reset_done [i] = jiffies + msecs_to_jiffies (20);
-                       mod_timer (&hcd->rh_timer,
-                                       ehci->reset_done [i] + 1);
                        ehci_dbg (ehci, "port %d remote wakeup\n", i + 1);
+                       usb_hcd_resume_root_hub(hcd);
                }
        }
 

diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index 88cb4ad..82caf33 100644 (file)
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -94,6 +94,13 @@ static int ehci_bus_resume (struct usb_hcd *hcd)
                msleep(5);
        spin_lock_irq (&ehci->lock);
 
+       /* Ideally and we've got a real resume here, and no port's power
+        * was lost.  (For PCI, that means Vaux was maintained.)  But we
+        * could instead be restoring a swsusp snapshot -- so that BIOS was
+        * the last user of the controller, not reset/pm hardware keeping
+        * state we gave to it.
+        */
+
        /* re-init operational registers in case we lost power */
        if (readl (&ehci->regs->intr_enable) == 0) {
                /* at least some APM implementations will try to deliver

diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
index dfd9bd0..0f2be91 100644 (file)
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -235,10 +235,11 @@ static void ehci_pci_stop (struct usb_hcd *hcd)
 
 /* suspend/resume, section 4.3 */
 
-/* These routines rely on the bus (pci, platform, etc)
+/* These routines rely on the PCI bus glue
  * to handle powerdown and wakeup, and currently also on
  * transceivers that don't need any software attention to set up
  * the right sort of wakeup.
+ * Also they depend on separate root hub suspend/resume.
  */
 
 static int ehci_pci_suspend (struct usb_hcd *hcd, pm_message_t message)
@@ -246,17 +247,9 @@ static int ehci_pci_suspend (struct usb_hcd *hcd, pm_message_t message)
        struct ehci_hcd         *ehci = hcd_to_ehci (hcd);
 
        if (time_before (jiffies, ehci->next_statechange))
-               msleep (100);
-
-#ifdef CONFIG_USB_SUSPEND
-       (void) usb_suspend_device (hcd->self.root_hub);
-#else
-       usb_lock_device (hcd->self.root_hub);
-       (void) ehci_bus_suspend (hcd);
-       usb_unlock_device (hcd->self.root_hub);
-#endif
+               msleep (10);
 
-       // save (PCI) FLADJ in case of Vaux power loss
+       // could save FLADJ in case of Vaux power loss
        // ... we'd only use it to handle clock skew
 
        return 0;
@@ -269,13 +262,18 @@ static int ehci_pci_resume (struct usb_hcd *hcd)
        struct usb_device       *root = hcd->self.root_hub;
        int                     retval = -EINVAL;
 
-       // maybe restore (PCI) FLADJ
+       // maybe restore FLADJ
 
        if (time_before (jiffies, ehci->next_statechange))
                msleep (100);
 
+       /* If CF is clear, we lost PCI Vaux power and need to restart.  */
+       if (readl (&ehci->regs->configured_flag) != cpu_to_le32(FLAG_CF))
+               goto restart;
+
        /* If any port is suspended (or owned by the companion),
         * we know we can/must resume the HC (and mustn't reset it).
+        * We just defer that to the root hub code.
         */
        for (port = HCS_N_PORTS (ehci->hcs_params); port > 0; ) {
                u32     status;
@@ -283,42 +281,43 @@ static int ehci_pci_resume (struct usb_hcd *hcd)
                status = readl (&ehci->regs->port_status [port]);
                if (!(status & PORT_POWER))
                        continue;
-               if (status & (PORT_SUSPEND | PORT_OWNER)) {
-                       down (&hcd->self.root_hub->serialize);
-                       retval = ehci_bus_resume (hcd);
-                       up (&hcd->self.root_hub->serialize);
-                       break;
+               if (status & (PORT_SUSPEND | PORT_RESUME | PORT_OWNER)) {
+                       usb_hcd_resume_root_hub(hcd);
+                       return 0;
                }
+       }
+
+restart:
+       ehci_dbg(ehci, "lost power, restarting\n");
+       for (port = HCS_N_PORTS (ehci->hcs_params); port > 0; ) {
+               port--;
                if (!root->children [port])
                        continue;
-               dbg_port (ehci, __FUNCTION__, port + 1, status);
                usb_set_device_state (root->children[port],
                                        USB_STATE_NOTATTACHED);
        }
 
        /* Else reset, to cope with power loss or flush-to-storage
-        * style "resume" having activated BIOS during reboot.
+        * style "resume" having let BIOS kick in during reboot.
         */
-       if (port == 0) {
-               (void) ehci_halt (ehci);
-               (void) ehci_reset (ehci);
-               (void) ehci_pci_reset (hcd);
-
-               /* emptying the schedule aborts any urbs */
-               spin_lock_irq (&ehci->lock);
-               if (ehci->reclaim)
-                       ehci->reclaim_ready = 1;
-               ehci_work (ehci, NULL);
-               spin_unlock_irq (&ehci->lock);
-
-               /* restart; khubd will disconnect devices */
-               retval = ehci_run (hcd);
-
-               /* here we "know" root ports should always stay powered;
-                * but some controllers may lose all power.
-                */
-               ehci_port_power (ehci, 1);
-       }
+       (void) ehci_halt (ehci);
+       (void) ehci_reset (ehci);
+       (void) ehci_pci_reset (hcd);
+
+       /* emptying the schedule aborts any urbs */
+       spin_lock_irq (&ehci->lock);
+       if (ehci->reclaim)
+               ehci->reclaim_ready = 1;
+       ehci_work (ehci, NULL);
+       spin_unlock_irq (&ehci->lock);
+
+       /* restart; khubd will disconnect devices */
+       retval = ehci_run (hcd);
+
+       /* here we "know" root ports should always stay powered;
+        * but some controllers may lose all power.
+        */
+       ehci_port_power (ehci, 1);
 
        return retval;
 }