Merge tag 'for-usb-linus-2012-08-09' of git://git.kernel.org/pub/scm/linux/kernel/git/sarah/xhci into usb-linus

Intel xhci: Work around immediate reboot on shutdown.

Hi Greg,

I'm cleaning out my queue before I leave on vacation tomorrow, so here's
one more patch for 3.6.  It works around an issue on a couple Intel
Panther Point desktop systems that cause them to reboot about 10 seconds
after the user shutdowns the system.

Sarah Sharp

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.
  *

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) {}

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) {

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);

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 */