I experienced the following WARN with a Renesas uPD720201 controller : xhci_hcd 0000:02:00.0: WARN Successful completion on short TX: needs XHCI_TRUST Adding the XHCI_NEC_HOST quirk solved the issue. It's possible that this doesn't apply to all Renesas hosts, however it appears they only officially make 2 hosts, a 2 port (uPD720202) and 4 port (uPD720201) this patch assumes they both benefit from the NEC quirk. --- diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c index 3c898c1..6121411 100644 --- a/drivers/usb/host/xhci-pci.c +++ b/drivers/usb/host/xhci-pci.c @@ -38,6 +38,8 @@ #define PCI_DEVICE_ID_INTEL_LYNXPOINT_XHCI 0x8c31 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_XHCI 0x9c31 +#define PCI_VENDOR_ID_RENESAS 0x1912 + static const char hcd_name[] = "xhci_hcd"; /* called after powerup, by probe or system-pm "wakeup" */ @@ -95,6 +97,9 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci) if (pdev->vendor == PCI_VENDOR_ID_NEC) xhci->quirks |= XHCI_NEC_HOST; + if (pdev->vendor == PCI_VENDOR_ID_RENESAS) + xhci->quirks |= XHCI_NEC_HOST; + if (pdev->vendor == PCI_VENDOR_ID_AMD && xhci->hci_version == 0x96) xhci->quirks |= XHCI_AMD_0x96_HOST; -- 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