I have the following:
I used a .xib file for the cell, which
I don't think you should do that and probably you're doing something wrong but if you really-really need it then just have a property in your CustomCell
class.
weak var viewController : UIViewController
then when you create the cell in cellForRowAtIndexPath
set the property
cell.viewController = self
after that you can easily access the view controller from within the cell code:
self.viewController.doSomething()
But again, in my opinion, you should redesign your code. The cell should not care about the controller. It should care only about displaying itself and nothing else