[PATCH 1/2] net: dsa: fix phydev->speed being uninitialized for the CPU port fixed PHY

[Ramon Fried]

On Sat, Jan 15, 2022 at 6:46 PM Ramon Fried <rfried.dev at gmail.com> wrote:
>
> On Sun, Dec 5, 2021 at 1:01 AM Vladimir Oltean <vladimir.oltean at nxp.com> wrote:
> >
> > If the DSA API is going to allow drivers to do things such as:
> >
> > - phy_config in dsa_ops :: port_probe
> > - phy_startup in dsa_ops :: port_enable
> >
> > then it would actually be good if the ->port_probe() method would
> > actually be called in all cases before the ->port_enable() is.
> >
> > Currently this is true for user ports, but not true for the CPU port,
> > because the CPU port does not have a udevice registered for it (this is
> > all part of DSA's design). So the current issue is that after
> > phy_startup has finished for the CPU port, its phydev->speed is an
> > uninitialized value, because phy_config() was never called for the
> > priv->cpu_port_fixed_phy, and it is precisely phy_config() who copies
> > the speed into the phydev in the case of the fixed PHY driver.
> >
> > So we need to simulate a probing event for the CPU port by manually
> > calling the driver's ->port_probe() method for the CPU port.
> >
> > Fixes: 8a2982574854 ("net: dsa: introduce a .port_probe() method in struct dsa_ops")
> > Signed-off-by: Vladimir Oltean <vladimir.oltean at nxp.com>
> > ---
> >  net/dsa-uclass.c | 11 +++++++++++
> >  1 file changed, 11 insertions(+)
> >
> > diff --git a/net/dsa-uclass.c b/net/dsa-uclass.c
> > index 606b1539a776..9ff55a02fb23 100644
> > --- a/net/dsa-uclass.c
> > +++ b/net/dsa-uclass.c
> > @@ -466,6 +466,8 @@ static int dsa_pre_probe(struct udevice *dev)
> >  {
> >         struct dsa_pdata *pdata = dev_get_uclass_plat(dev);
> >         struct dsa_priv *priv = dev_get_uclass_priv(dev);
> > +       struct dsa_ops *ops = dsa_get_ops(dev);
> > +       int err;
> >
> >         priv->num_ports = pdata->num_ports;
> >         priv->cpu_port = pdata->cpu_port;
> > @@ -477,6 +479,15 @@ static int dsa_pre_probe(struct udevice *dev)
> >
> >         uclass_find_device_by_ofnode(UCLASS_ETH, pdata->master_node,
> >                                      &priv->master_dev);
> > +
> > +       /* Simulate a probing event for the CPU port */
> > +       if (ops->port_probe) {
> > +               err = ops->port_probe(dev, priv->cpu_port,
> > +                                     priv->cpu_port_fixed_phy);
> > +               if (err)
> > +                       return err;
> > +       }
> > +
> >         return 0;
> >  }
> >
> > --
> > 2.25.1
> >
> Reviewed-by: Ramon Fried <rfried.dev at gmail.com>
Applied to u-boot-net/next,
Thanks !