How to communicate nested component to mixin without using service

I have a nested component. The child-component has an input field bind with mixin variable and action, In parent-component had button action. ( without mixin because parent-component considered as a addon ) while button action triggers the child-component value update to the mixin variable. How trigger a child action from parent-component.

Note: Please refer the attached demo link

http://ift.tt/1SxhKAX