usb: xhci: Fix config fail of FS hub behind a HS hub with MTT

[platform/kernel/u-boot.git] / drivers / usb / host / xhci.c

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 8c1126e..f9c6bbb 100644 (file)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1435,8 +1435,15 @@ static int xhci_update_hub_device(struct udevice *dev, struct usb_device *udev)
 
        /* Update hub related fields */
        slot_ctx->dev_info |= cpu_to_le32(DEV_HUB);
-       if (hub->tt.multi && udev->speed == USB_SPEED_HIGH)
+       /*
+        * refer to section 6.2.2: MTT should be 0 for full speed hub,
+        * but it may be already set to 1 when setup an xHCI virtual
+        * device, so clear it anyway.
+        */
+       if (hub->tt.multi)
                slot_ctx->dev_info |= cpu_to_le32(DEV_MTT);
+       else if (udev->speed == USB_SPEED_FULL)
+               slot_ctx->dev_info &= cpu_to_le32(~DEV_MTT);
        slot_ctx->dev_info2 |= cpu_to_le32(XHCI_MAX_PORTS(udev->maxchild));
        /*
         * Set TT think time - convert from ns to FS bit times.