lsusb -t result from 201307-14037, which has the same chipset but everything works as expected. You can see here this device is on level 1, with a hub driven by xhci_hcd driver
/: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/4p, 5000M
/: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/9p, 480M
|__ Port 3: Dev 6, If 0, Class=stor., Driver=usb-storage, 480M
|__ Port 4: Dev 2, If 0, Class=vend., Driver=, 12M
|__ Port 5: Dev 3, If 0, Class='bInterfaceClass 0x0e not yet handled', Driver=uvcvideo, 480M
|__ Port 5: Dev 3, If 1, Class='bInterfaceClass 0x0e not yet handled', Driver=uvcvideo, 480M
|__ Port 7: Dev 4, If 0, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M
|__ Port 7: Dev 4, If 1, Class='bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M
/: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M
|__ Port 1: Dev 2, If 0, Class=hub, Driver=hub/8p, 480M
lsusb -t result from 201307-14037, which has the same chipset but everything works as expected. You can see here this device is on level 1, with a hub driven by xhci_hcd driver bInterfaceClass 0x0e not yet handled', Driver=uvcvideo, 480M bInterfaceClass 0x0e not yet handled', Driver=uvcvideo, 480M bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M bInterfaceClass 0xe0 not yet handled', Driver=btusb, 12M
/: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/4p, 5000M
/: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/9p, 480M
|__ Port 3: Dev 6, If 0, Class=stor., Driver=usb-storage, 480M
|__ Port 4: Dev 2, If 0, Class=vend., Driver=, 12M
|__ Port 5: Dev 3, If 0, Class='
|__ Port 5: Dev 3, If 1, Class='
|__ Port 7: Dev 4, If 0, Class='
|__ Port 7: Dev 4, If 1, Class='
/: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M
|__ Port 1: Dev 2, If 0, Class=hub, Driver=hub/8p, 480M