Exiting a station yesterday, I noticed that the manual gate had disappeared: just a long row of machines, though with a staff member standing next to one. I went there and she showed me how to put my passport in a scanner slot in the gate, and what do you know, it opened. Don't know whether all the gates were so equipped; there were no signs in Chinese (or English) directing passport holders where to go, though there was a foggy loudspeaker announcement I couldn't quite grasp.

Entering there was a manual gate, so I didn't check whether passports could be used in the automatic gates there, as well.