How to set ember controller inside a directory?

I have a route defined as follows

export default Router.map(function () {

        this.route('home', {path: 'homepage'});
});

Normally ember will then load controller named home inside controllers folder

But I want to map a controller inside a another directory inside controllers folder. my controller directory is as follows

--app
  --controllers
    --homePage
       home.js

How can I map route to home.js controller? Appreciate any help