#include <linux/usb/otg.h>
 #include <linux/of_platform.h>
 
+static const char *const ep_type_names[] = {
+       [USB_ENDPOINT_XFER_CONTROL] = "ctrl",
+       [USB_ENDPOINT_XFER_ISOC] = "isoc",
+       [USB_ENDPOINT_XFER_BULK] = "bulk",
+       [USB_ENDPOINT_XFER_INT] = "intr",
+};
+
+const char *usb_ep_type_string(int ep_type)
+{
+       if (ep_type < 0 || ep_type >= ARRAY_SIZE(ep_type_names))
+               return "unknown";
+
+       return ep_type_names[ep_type];
+}
+EXPORT_SYMBOL_GPL(usb_ep_type_string);
+
 const char *usb_otg_state_string(enum usb_otg_state state)
 {
        static const char *const names[] = {
 
                /* kick hcd */
                unlink1(hcd, urb, -ESHUTDOWN);
                dev_dbg (hcd->self.controller,
-                       "shutdown urb %pK ep%d%s%s\n",
+                       "shutdown urb %pK ep%d%s-%s\n",
                        urb, usb_endpoint_num(&ep->desc),
                        is_in ? "in" : "out",
-                       ({      char *s;
-
-                                switch (usb_endpoint_type(&ep->desc)) {
-                                case USB_ENDPOINT_XFER_CONTROL:
-                                       s = ""; break;
-                                case USB_ENDPOINT_XFER_BULK:
-                                       s = "-bulk"; break;
-                                case USB_ENDPOINT_XFER_INT:
-                                       s = "-intr"; break;
-                                default:
-                                       s = "-iso"; break;
-                               };
-                               s;
-                       }));
+                       usb_ep_type_string(usb_endpoint_type(&ep->desc)));
                usb_put_urb (urb);
 
                /* list contents may have changed */
 
 static int ast_vhub_epn_enable(struct usb_ep* u_ep,
                               const struct usb_endpoint_descriptor *desc)
 {
-       static const char *ep_type_string[] __maybe_unused = { "ctrl",
-                                                              "isoc",
-                                                              "bulk",
-                                                              "intr" };
        struct ast_vhub_ep *ep = to_ast_ep(u_ep);
        struct ast_vhub_dev *dev;
        struct ast_vhub *vhub;
        ep->epn.wedged = false;
 
        EPDBG(ep, "Enabling [%s] %s num %d maxpacket=%d\n",
-             ep->epn.is_in ? "in" : "out", ep_type_string[type],
+             ep->epn.is_in ? "in" : "out", usb_ep_type_string(type),
              usb_endpoint_num(desc), maxpacket);
 
        /* Can we use DMA descriptor mode ? */
 
                _ep->name,
                desc->bEndpointAddress & 0x0f,
                (desc->bEndpointAddress & USB_DIR_IN) ? "in" : "out",
-               ({ char *val;
-                switch (usb_endpoint_type(desc)) {
-                case USB_ENDPOINT_XFER_BULK:
-                        val = "bulk";
-                        break;
-                case USB_ENDPOINT_XFER_ISOC:
-                        val = "iso";
-                        break;
-                case USB_ENDPOINT_XFER_INT:
-                        val = "intr";
-                        break;
-                default:
-                        val = "ctrl";
-                        break;
-                } val; }),
+               usb_ep_type_string(usb_endpoint_type(desc)),
                max, ep->stream_en ? "enabled" : "disabled");
 
        /* at this point real hardware should be NAKing transfers
 
 #include <linux/device.h>
 #include <uapi/linux/usb/ch9.h>
 
+/**
+ * usb_ep_type_string() - Returns human readable-name of the endpoint type.
+ * @ep_type: The endpoint type to return human-readable name for.  If it's not
+ *   any of the types: USB_ENDPOINT_XFER_{CONTROL, ISOC, BULK, INT},
+ *   usually got by usb_endpoint_type(), the string 'unknown' will be returned.
+ */
+extern const char *usb_ep_type_string(int ep_type);
+
 /**
  * usb_speed_string() - Returns human readable-name of the speed.
  * @speed: The speed to return human-readable name for.  If it's not