[Unsupported] Kasda KW5815u ADSL (ISP provided) Router

I have a ISP provided router, which says Kasda KW5815u on the back of the router and the board says KW5815X Rev:1.2. There is no rev. on the back of the router. It has BCM 6318 cpu and I have a couple of good quality pics (not high-res).

I first downloaded Openwrt firmware for F@2740N router and it worked as that it can only run 1 wifi network at a time. If you create more than one wifi network (1 sta and 1 AP) wifi gets disabled.
I also used AR5315 firmware from LEDE project and same thing is happening with wifi but i cant find any ADSL interface installed in the system. I wonder how can i detect it.
LEDs kinda work a bit and you can use it as a wifi extender as long as you connect through the lan ports. Maybe that can be fixed but I dont know yet.

Pics: KW5815u

Can someone look at the pics and advise what can i do to make ADSL work on the device if it is possible?

As with all BCM63xx, internal DSL is not supported on the AR5315u.