xhci: Add helper to get xhci roothub from hcd

quick way to get the xhci roothub and thus all the ports
belonging to a certain hcd
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/xhci-hub.c

@@ -554,6 +554,15 @@ static int xhci_get_ports(struct usb_hcd *hcd, __le32 __iomem ***port_array)
 	return max_ports;
 }
 
+struct xhci_hub *xhci_get_rhub(struct usb_hcd *hcd)
+{
+	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
+
+	if (hcd->speed >= HCD_USB3)
+		return &xhci->usb3_rhub;
+	return &xhci->usb2_rhub;
+}
+
 static __le32 __iomem *xhci_get_port_io_addr(struct usb_hcd *hcd, int index)
 {
 	__le32 __iomem **port_array;

drivers/usb/host/xhci.h

@@ -2110,6 +2110,8 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue, u16 wIndex,
 		char *buf, u16 wLength);
 int xhci_hub_status_data(struct usb_hcd *hcd, char *buf);
 int xhci_find_raw_port_number(struct usb_hcd *hcd, int port1);
+struct xhci_hub *xhci_get_rhub(struct usb_hcd *hcd);
+
 void xhci_hc_died(struct xhci_hcd *xhci);
 
 #ifdef CONFIG_PM