My main router is pfSense and I have 4 VLANs configured there all is working just fine.
Question:
Can DD-WRT recognise my 2 VLANs, one would be for private NET and another for Public net.
I have VLAN 10 for private and VLAN 192 for public.
Also, I have created 2 WLANs on DD-WRT.
DHCP, gateway and everything else is on my pfSense router, DD-WRT would only be for wireless access and nothing more.
It´s possible do this with ddwrt, I used it on Tplink TL-WR740 and 741 (almost sure that possible on any TP-link supported).
You have to pass the vlan on br0 and then create another bridge between ath0.1 and vlan100 (in my case).
Works like a charm.
Ask for more info if needed.