Restore parts of an image with the History Brush tool

Choose Window > History to open the History panel.  

In the History panel, click the far-left column of the state that you want to use as the source for the History Brush tool. A brush icon will appear next to the selected history state.

Select the History Brush tool (Y) . 

Use the Options bar to customize tool settings, like Size and Hardness, to get the effect you want.

Drag over the parts of the image you want to restore.