The Intel desktop boards DH77EB and DH77DF have a hardware issue that can be worked around by BIOS. If the USB ports are switched to xHCI on shutdown, the xHCI host will send a spurious interrupt, which will wake the system. Some BIOS will work around this, but not all. The bug can be avoided if the USB ports are switched back to EHCI on shutdown. The Intel Windows driver switches the ports back to EHCI, so change the Linux xHCI driver to do the same. Unfortunately, we can't tell the two effected boards apart from other working motherboards, because the vendors will change the DMI strings for the DH77EB and DH77DF boards to their own custom names. One example is Compulab's mini-desktop, the Intense-PC. Instead, key off the Panther Point xHCI host PCI vendor and device ID, and switch the ports over for all PPT xHCI hosts. The only impact this will have on non-effected boards is to add a couple hundred milliseconds delay on boot when the BIOS has to switch the ports over from EHCI to xHCI. This patch should be backported to kernels as old as 3.0, that contain the commit 69e848c2090aebba5698a1620604c7dccb448684 "Intel xhci: Support EHCI/xHCI port switching." Signed-off-by: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx> Reported-by: Denis Turischev <denis@xxxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx --- drivers/usb/host/pci-quirks.c | 7 +++++++ drivers/usb/host/pci-quirks.h | 1 + drivers/usb/host/xhci-pci.c | 9 +++++++++ drivers/usb/host/xhci.c | 3 +++ drivers/usb/host/xhci.h | 1 + 5 files changed, 21 insertions(+), 0 deletions(-) diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c index df0828c..c5e9e4a 100644 --- a/drivers/usb/host/pci-quirks.c +++ b/drivers/usb/host/pci-quirks.c @@ -800,6 +800,13 @@ void usb_enable_xhci_ports(struct pci_dev *xhci_pdev) } EXPORT_SYMBOL_GPL(usb_enable_xhci_ports); +void usb_disable_xhci_ports(struct pci_dev *xhci_pdev) +{ + pci_write_config_dword(xhci_pdev, USB_INTEL_USB3_PSSEN, 0x0); + pci_write_config_dword(xhci_pdev, USB_INTEL_XUSB2PR, 0x0); +} +EXPORT_SYMBOL_GPL(usb_disable_xhci_ports); + /** * PCI Quirks for xHCI. * diff --git a/drivers/usb/host/pci-quirks.h b/drivers/usb/host/pci-quirks.h index b1002a8..ef004a5 100644 --- a/drivers/usb/host/pci-quirks.h +++ b/drivers/usb/host/pci-quirks.h @@ -10,6 +10,7 @@ void usb_amd_quirk_pll_disable(void); void usb_amd_quirk_pll_enable(void); bool usb_is_intel_switchable_xhci(struct pci_dev *pdev); void usb_enable_xhci_ports(struct pci_dev *xhci_pdev); +void usb_disable_xhci_ports(struct pci_dev *xhci_pdev); #else static inline void usb_amd_quirk_pll_disable(void) {} static inline void usb_amd_quirk_pll_enable(void) {} diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c index 92eaff6..9bfd4ca11 100644 --- a/drivers/usb/host/xhci-pci.c +++ b/drivers/usb/host/xhci-pci.c @@ -94,6 +94,15 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci) xhci->quirks |= XHCI_EP_LIMIT_QUIRK; xhci->limit_active_eps = 64; xhci->quirks |= XHCI_SW_BW_CHECKING; + /* + * PPT desktop boards DH77EB and DH77DF will power back on after + * a few seconds of being shutdown. The fix for this is to + * switch the ports from xHCI to EHCI on shutdown. We can't use + * DMI information to find those particular boards (since each + * vendor will change the board name), so we have to key off all + * PPT chipsets. + */ + xhci->quirks |= XHCI_SPURIOUS_REBOOT; } if (pdev->vendor == PCI_VENDOR_ID_ETRON && pdev->device == PCI_DEVICE_ID_ASROCK_P67) { diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 95394e5..81aa10c 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -659,6 +659,9 @@ void xhci_shutdown(struct usb_hcd *hcd) { struct xhci_hcd *xhci = hcd_to_xhci(hcd); + if (xhci->quirks && XHCI_SPURIOUS_REBOOT) + usb_disable_xhci_ports(to_pci_dev(hcd->self.controller)); + spin_lock_irq(&xhci->lock); xhci_halt(xhci); spin_unlock_irq(&xhci->lock); diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index 96f49db..c713256 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1494,6 +1494,7 @@ struct xhci_hcd { #define XHCI_TRUST_TX_LENGTH (1 << 10) #define XHCI_LPM_SUPPORT (1 << 11) #define XHCI_INTEL_HOST (1 << 12) +#define XHCI_SPURIOUS_REBOOT (1 << 13) unsigned int num_active_eps; unsigned int limit_active_eps; /* There are two roothubs to keep track of bus suspend info for */ -- 1.7.9 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html