diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index 60a45f1e3a67e13b41fd41770d51cbe83b39f730..f2f055eb6831d73dc006b7e3f54e1e954437c6f4 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -1022,6 +1022,14 @@ static int usb_resume_device(struct usb_device *udev, pm_message_t msg)
goto done;
}
+ /* Non-root devices on a full/low-speed bus must wait for their
+ * companion high-speed root hub, in case a handoff is needed.
+ */
+ if (!(msg.event & PM_EVENT_AUTO) && udev->parent &&
+ udev->bus->hs_companion)
+ device_pm_wait_for_dev(&udev->dev,
+ &udev->bus->hs_companion->root_hub->dev);
+
if (udev->quirks & USB_QUIRK_RESET_RESUME)
udev->reset_resume = 1;
diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c
index 2dcf906df569440d18a0cecb9b4801dec581e77f..15286533c15ac5c315712d30ed3a23c2e7bf3a73 100644
--- a/drivers/usb/core/hcd-pci.c
+++ b/drivers/usb/core/hcd-pci.c
@@ -19,6 +19,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
+#include <linux/pm_runtime.h>
#include <linux/usb.h>
#include <asm/io.h>
@@ -37,6 +38,122 @@
/* PCI-based HCs are common, but plenty of non-PCI HCs are used too */
+#ifdef CONFIG_PM_SLEEP
+
+/* Coordinate handoffs between EHCI and companion controllers
+ * during system resume
+ */
+
+static DEFINE_MUTEX(companions_mutex);
+
+#define CL_UHCI PCI_CLASS_SERIAL_USB_UHCI
+#define CL_OHCI PCI_CLASS_SERIAL_USB_OHCI
+#define CL_EHCI PCI_CLASS_SERIAL_USB_EHCI
+
+enum companion_action {
+ SET_HS_COMPANION, CLEAR_HS_COMPANION, WAIT_FOR_COMPANIONS
+};
+
+static void companion_common(struct pci_dev *pdev, struct usb_hcd *hcd,
+ enum companion_action action)
+{
+ struct pci_dev *companion;
+ struct usb_hcd *companion_hcd;
+ unsigned int slot = PCI_SLOT(pdev->devfn);
+
+ /* Iterate through other PCI functions in the same slot.
+ * If pdev is OHCI or UHCI then we are looking for EHCI, and
+ * vice versa.
+ */
+ companion = NULL;
+ for (;;) {
+ companion = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, companion);
+ if (!companion)
+ break;
+ if (companion->bus != pdev->bus ||
+ PCI_SLOT(companion->devfn) != slot)
+ continue;
+
+ companion_hcd = pci_get_drvdata(companion);
+ if (!companion_hcd)
+ continue;
+
+ /* For SET_HS_COMPANION, store a pointer to the EHCI bus in
+ * the OHCI/UHCI companion bus structure.
+ * For CLEAR_HS_COMPANION, clear the pointer to the EHCI bus
+ * in the OHCI/UHCI companion bus structure.
+ * For WAIT_FOR_COMPANIONS, wait until the OHCI/UHCI
+ * companion controllers have fully resumed.
+ */
+
+ if ((pdev->class == CL_OHCI || pdev->class == CL_UHCI) &&
+ companion->class == CL_EHCI) {
+ /* action must be SET_HS_COMPANION */
+ dev_dbg(&companion->dev, "HS companion for %s\n",
+ dev_name(&pdev->dev));
+ hcd->self.hs_companion = &companion_hcd->self;
+
+ } else if (pdev->class == CL_EHCI &&
+ (companion->class == CL_OHCI ||
+ companion->class == CL_UHCI)) {
+ switch (action) {
+ case SET_HS_COMPANION:
+ dev_dbg(&pdev->dev, "HS companion for %s\n",
+ dev_name(&companion->dev));
+ companion_hcd->self.hs_companion = &hcd->self;
+ break;
+ case CLEAR_HS_COMPANION:
+ companion_hcd->self.hs_companion = NULL;
+ break;
+ case WAIT_FOR_COMPANIONS:
+ device_pm_wait_for_dev(&pdev->dev,
+ &companion->dev);
+ break;
+ }
+ }
+ }
+}
+
+static void set_hs_companion(struct pci_dev *pdev, struct usb_hcd *hcd)
+{
+ mutex_lock(&companions_mutex);
+ dev_set_drvdata(&pdev->dev, hcd);
+ companion_common(pdev, hcd, SET_HS_COMPANION);
+ mutex_unlock(&companions_mutex);
+}
+
+static void clear_hs_companion(struct pci_dev *pdev, struct usb_hcd *hcd)
+{
+ mutex_lock(&companions_mutex);
+ dev_set_drvdata(&pdev->dev, NULL);
+
+ /* If pdev is OHCI or UHCI, just clear its hs_companion pointer */
+ if (pdev->class == CL_OHCI || pdev->class == CL_UHCI)
+ hcd->self.hs_companion = NULL;
+
+ /* Otherwise search for companion buses and clear their pointers */
+ else
+ companion_common(pdev, hcd, CLEAR_HS_COMPANION);
+ mutex_unlock(&companions_mutex);
+}
+
+static void wait_for_companions(struct pci_dev *pdev, struct usb_hcd *hcd)
+{
+ /* Only EHCI controllers need to wait.
+ * No locking is needed because a controller cannot be resumed
+ * while one of its companions is getting unbound.
+ */
+ if (pdev->class == CL_EHCI)
+ companion_common(pdev, hcd, WAIT_FOR_COMPANIONS);
+}
+
+#else /* !CONFIG_PM_SLEEP */
+
+static inline void set_hs_companion(struct pci_dev *d, struct usb_hcd *h) {}
+static inline void clear_hs_companion(struct pci_dev *d, struct usb_hcd *h) {}
+static inline void wait_for_companions(struct pci_dev *d, struct usb_hcd *h) {}
+
+#endif /* !CONFIG_PM_SLEEP */
/*-------------------------------------------------------------------------*/
@@ -123,7 +240,7 @@ int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
if (region == PCI_ROM_RESOURCE) {
dev_dbg(&dev->dev, "no i/o regions available\n");
retval = -EBUSY;
- goto err1;
+ goto err2;
}
}
@@ -132,6 +249,7 @@ int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
retval = usb_add_hcd(hcd, dev->irq, IRQF_DISABLED | IRQF_SHARED);
if (retval != 0)
goto err4;
+ set_hs_companion(dev, hcd);
return retval;
err4:
@@ -142,6 +260,7 @@ int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
} else
release_region(hcd->rsrc_start, hcd->rsrc_len);
err2:
+ clear_hs_companion(dev, hcd);
usb_put_hcd(hcd);
err1:
pci_disable_device(dev);
@@ -180,6 +299,7 @@ void usb_hcd_pci_remove(struct pci_dev *dev)
} else {
release_region(hcd->rsrc_start, hcd->rsrc_len);
}
+ clear_hs_companion(dev, hcd);
usb_put_hcd(hcd);
pci_disable_device(dev);
}
@@ -344,6 +464,11 @@ static int resume_common(struct device *dev, bool hibernated)
clear_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
if (hcd->driver->pci_resume) {
+ /* This call should be made only during system resume,
+ * not during runtime resume.
+ */
+ wait_for_companions(pci_dev, hcd);
+
retval = hcd->driver->pci_resume(hcd, hibernated);
if (retval) {
dev_err(dev, "PCI post-resume error %d!\n", retval);
diff --git a/include/linux/usb.h b/include/linux/usb.h
index d7ace1b80f09d0936c1f2f23e8a62b82f1c5baa7..332eaea610217aab63378e27daf8afe3720b6a6c 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -339,6 +339,7 @@ struct usb_bus {
struct usb_devmap devmap; /* device address allocation map */
struct usb_device *root_hub; /* Root hub */
+ struct usb_bus *hs_companion; /* Companion EHCI bus, if any */
struct list_head bus_list; /* list of busses */
int bandwidth_allocated; /* on this bus: how much of the time