Erro uninitialized constant Devise::OmniAuthCallbacksController

Question

While implementing OmniAuth in devise under rails 4 i get the following error:

uninitialized constant Devise::OmniAuthCallbacksController
app/controllers/usuarios/omniauth_callbacks_controller.rb:1:in `<top (required)>'

Its like i am unable to extend Devise::OmniAuthCallbacksController

my file is:

class Usuarios::OmniauthCallbacksController < Devise::OmniAuthCallbacksController
   def all
  end
  alias_method :office365, :all 
end

My gems

gem 'devise' gem 'omniauth' gem 'omniauth-office365'

User model

class Usuario < ActiveRecord::Base
  devise :database_authenticatable, :registerable,:recoverable, :rememberable, :trackable, :validatable, :omniauthable, 
  :omniauth_providers => [:outlook365]

end

Thanks.