Combine multiple calls to one Javascript function

Question

Here is the situation: I have one JS file (getInfo.js) that contains a function with ajax.

define(["underscore", "jquery", "domReady!"],
function (_, $) {
return function (opUrl, opList, onCallback) {

        // IRRELEVANT CODE 

      self.getFetch = function (optionName) { ...

and multiple other JS files calls this function

var test = new getInfo(opUrl, opList, onCallback);
var getJuice = test.getfetch("DataStorage);

Is there a way to make these functions call from different JS file Asynchronous? Or how can I make the getInfo.js script to wait for all the call to be done before fetching from ajax

Thanks!