--- linux-4.9.37/drivers/usb/gadget/composite.c	2017-07-12 16:42:41.000000000 +0300
+++ linux-4.9.y/drivers/usb/gadget/composite.c	2021-06-07 13:01:34.000000000 +0300
@@ -205,7 +205,7 @@
 
 	if (g->speed == USB_SPEED_HIGH && (usb_endpoint_xfer_isoc(_ep->desc) ||
 				usb_endpoint_xfer_int(_ep->desc)))
-		_ep->mult = ((usb_endpoint_maxp(_ep->desc) & 0x1800) >> 11) + 1;
+		_ep->mult = usb_endpoint_maxp_mult(_ep->desc);
 
 	if (!want_comp_desc)
 		return 0;
@@ -315,6 +315,9 @@
 	list_del(&f->list);
 	if (f->unbind)
 		f->unbind(c, f);
+
+	if (f->bind_deactivated)
+		usb_function_activate(f);
 }
 EXPORT_SYMBOL_GPL(usb_remove_function);
 
@@ -956,12 +959,8 @@
 
 		f = list_first_entry(&config->functions,
 				struct usb_function, list);
-		list_del(&f->list);
-		if (f->unbind) {
-			DBG(cdev, "unbind function '%s'/%p\n", f->name, f);
-			f->unbind(config, f);
-			/* may free memory for "f" */
-		}
+
+		usb_remove_function(config, f);
 	}
 	list_del(&config->list);
 	if (config->unbind) {