Re: [PATCH net v1] net: dsa: ksz8795: use correct number of physical ports

[Andrew Lunn]

On Fri, Dec 04, 2020 at 03:24:56PM -0800, Jakub Kicinski wrote:
> On Thu,  3 Dec 2020 16:46:45 -0500 Sven Van Asbroeck wrote:
> > From: Sven Van Asbroeck <thesven73@xxxxxxxxx>
> > 
> > The ksz8795 has five physical ports, but the driver assumes
> > it has only four. This prevents the driver from working correctly.
> > 
> > Fix by indicating the correct number of physical ports.
> > 
> > Fixes: e66f840c08a23 ("net: dsa: ksz: Add Microchip KSZ8795 DSA driver")
> > Tested-by: Sven Van Asbroeck <thesven73@xxxxxxxxx> # ksz8795
> > Signed-off-by: Sven Van Asbroeck <thesven73@xxxxxxxxx>
> 
> All the port counts here are -1 compared to datasheets, so I'm assuming
> the are not supposed to include the host facing port or something?
> 
> Can you describe the exact problem you're trying to solve?
> 
> DSA devices are not supposed to have a netdev for the host facing port
> on the switch (sorry for stating the obvious).

Hi Jakub

It is the DSA core layer which takes care of that creating/not
creating netdevs. The switch should declare all the ports it has.

There has been issues with the ksz collection of drivers having
different meanings for port_cnt. There recently was some changes in
this area, maybe it broke something?

     Andrew