I've found a lot of good documentation on the wiki about networking and vlans but they all seem to say it only works for broadcom.

I am trying to figure out how i can set up my home network using a switch and a Fon with Openwrt.

The Fon only has one ethernet port but I was wondering if it's possible to:
    - assign the external internet and my internal network to two different vlans on a switch
    - bridge them through the Fon with the fon acting as the DHCP server for the internal network
    - obtaining an exernal ip address from the external network through the ISP's DHCP server
(similar to the Firewall example given on section 1.2 of this page: http://wiki.openwrt.org/OpenWrtDocs/NetworkInterfaces ).