One button to return to the landing configuration is a good idea.
But my mantra in UX is... "Simple stuff should be easy, hard stuff should be possible"
In this case it means you also need a one button "turn it into a bed" and a one button "go the reclined position average" with it being obvious how to adjust the individual movable elements after that but perhaps at one level removed from the first set of buttons.
And for the first three you also need a 'stop' button so that you can use them as shortcuts to quickly get to the nearest place to what you want without having to 'go all the way'.