Lightroom can't read layers and it can't read smart objects from Photoshop. All it reads is a flattened composite, inserted into the file in Photoshop. What you get is a flat image with Lightroom adjustments, all the previous history is gone.
For this reason, roundtripping is usually just a ticket to confusion and chaos. Start in Lightroom, finish in Photoshop, done. One way. Don't go against the natural flow.
It can be done if you know what you're doing and are acutely aware of the above. If not, don't do it.