Rails jsonp request with angular

home_controller.rb

class HomeController < ApplicationController
	def testtest
		puts '########################################'
		response = params[:test]
		render :json => response.to_json, :callback => params['callback']
	end
end

request.js

  $http.jsonp('/testtest?callback=JSON_CALLBACK&test=hello').
    success(function(data, status, headers, config) {
        //what do I do here?
        alert(data);
    }).
    error(function(data, status, headers, config) {
        alert(status);
        // $scope.error = true;
    });
  

routes.rb

Myapp::Application.routes.draw do
 get 'testtest' => 'home#testtest'
end