+/* check if a usb2 port supports a given extened capability protocol
+ * only USB2 ports extended protocol capability values are cached.
+ * Return 1 if capability is supported
+ */
+static int xhci_check_usb2_port_capability(struct xhci_hcd *xhci, int port,
+ unsigned capability)
+{
+ u32 port_offset, port_count;
+ int i;
+
+ for (i = 0; i < xhci->num_ext_caps; i++) {
+ if (xhci->ext_caps[i] & capability) {
+ /* port offsets starts at 1 */
+ port_offset = XHCI_EXT_PORT_OFF(xhci->ext_caps[i]) - 1;
+ port_count = XHCI_EXT_PORT_COUNT(xhci->ext_caps[i]);
+ if (port >= port_offset &&
+ port < port_offset + port_count)
+ return 1;
+ }
+ }
+ return 0;
+}
+