Re: [PATCH RFC net-next 5/7] net: dsa: avoid DT validation for drivers which provide default config

["Russell King (Oracle)" <linux@armlinux.org.uk>]

On Wed, Mar 22, 2023 at 09:14:31PM +0100, Andrew Lunn wrote:
> On Wed, Mar 22, 2023 at 08:09:12PM +0000, Russell King (Oracle) wrote:
> > On Wed, Mar 22, 2023 at 07:51:22PM +0100, Andrew Lunn wrote:
> > > On Wed, Mar 22, 2023 at 12:00:16PM +0000, Russell King (Oracle) wrote:
> > > > When a DSA driver (e.g. mv88e6xxx) provides a default configuration,
> > > > avoid validating the DT description as missing elements will be
> > > > provided by the DSA driver.
> > > > 
> > > > Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
> > > > ---
> > > >  net/dsa/port.c | 3 +++
> > > >  1 file changed, 3 insertions(+)
> > > > 
> > > > diff --git a/net/dsa/port.c b/net/dsa/port.c
> > > > index c30e3a7d2145..23d9970c02d3 100644
> > > > --- a/net/dsa/port.c
> > > > +++ b/net/dsa/port.c
> > > > @@ -1951,6 +1951,9 @@ static void dsa_shared_port_validate_of(struct dsa_port *dp,
> > > >  	*missing_phy_mode = false;
> > > >  	*missing_link_description = false;
> > > >  
> > > > +	if (dp->ds->ops->port_get_fwnode)
> > > > +		return;
> > > 
> > > I wounder if you should actually call it for the given port, and
> > > ensure it does not return -EOPNOTSUPP, or -EINVAL, etc, because it is
> > > not going to override that port? Then the DT values should be
> > > validated?
> > 
> > Won't that mean that we need to implement the method for all DSA
> > drivers?
> 
> I mean call it if it exists. We should be only providing overrides for
> CPU and DSA ports, i think. So i expect it returns an error for user
> ports? And then we want to continue with the validation with what
> actually is in DT for user ports.

I suppose we could do - but before adding that complexity, I think we
should have a real use case for it.

-- 
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