Realtek RTS5401 USB 3.0 hub

[Warren Block]

On Tue, 22 Mar 2016, Warren Block wrote:

> This Realtek RTS5401 USB 3.0 hub is combined in a case with three USB 3.0 
> ports and a Realtek RTL8153 Gigabit Ethernet adapter.
>
> Connected to a USB 2.0 port, it shows this:
>
>  ugen1.3: <Realtek> at usbus1
>  uhub4: <Realtek USB3.0 Hub, class 9/0, rev 2.10/1.11, addr 3> on usbus1
>  uhub4: MTT could not be enabled
>  device_attach: uhub4 attach returned 6
>
> I have not tried it on a USB 3.0 port yet.
>
> It would not really bother me if only the Ethernet worked, but surely it is 
> connected to the hub, so will be all or nothing.  Any suggestions?

On a USB 3.0 port on a -CURRENT system (r297315), the hub is recognized 
and works:

   ugen 0.2: <Realtek> at usbus0
   uhub1: <Realtek USB3.0 Hub, class 9/0, rev 2.10/1.11, addr 10> on usbus0
   uhub1: MTT could not be enabled
   device_attach: uhub1 attach returned 6
   ugen0.3: <Realtek> at usbus0
   uhub1: <Interrupt In Interface> on usbus0
   uhub1: 4 ports with 4 removable, self powered

Are USB 3 hubs not backwards compatible?  Maybe just this one 
specifically?  USB 2.0 devices like mice are not recognized when 
attached.  A USB 3.0 memory stick is recognized.

The attached Ethernet port is still not seen.  Should rue(4) support the 
RTL8153?