Re: [PATCH net-next 05/15] net: dsa: mt7530: improve code path for setting up port 5

[Arınç ÜNAL]

On 18.11.2023 17:41, Russell King (Oracle) wrote:
> On Sat, Nov 18, 2023 at 03:31:55PM +0300, Arınç ÜNAL wrote:
> > There're two code paths for setting up port 5:
> >
> > mt7530_setup()
> > -> mt7530_setup_port5()
> >
> > mt753x_phylink_mac_config()
> > -> mt753x_mac_config()
> >     -> mt7530_mac_config()
> >        -> mt7530_setup_port5()
> >
> > Currently mt7530_setup_port5() from mt7530_setup() always runs. If port 5
> > is used as a CPU, DSA, or user port, mt7530_setup_port5() from
> > mt753x_phylink_mac_config() won't run. That is because priv->p5_interface
> > set on mt7530_setup_port5() will match state->interface on
> > mt753x_phylink_mac_config() which will stop running mt7530_setup_port5()
> > again.
> >
> > Therefore, mt7530_setup_port5() will never run from
> > mt753x_phylink_mac_config().
> >
> > Address this by not running mt7530_setup_port5() from mt7530_setup() if
> > port 5 is used as a CPU, DSA, or user port. This driver isn't in the
> > dsa_switches_apply_workarounds[] array so phylink will always be present.
> >
> > For the cases of PHY muxing or the port being disabled, call
> > mt7530_setup_port5() from mt7530_setup(). mt7530_setup_port5() from
> > mt753x_phylink_mac_config() won't run when port 5 is disabled or used for
> > PHY muxing as port 5 won't be defined on the devicetree.
>
> ... and this should state why this needs to happen - in other words,
> the commit message should state why is it critical that port 5 is
> always setup.

Actually, port 5 must not always be setup. With patch 7, I explain this
while preventing mt7530_setup_port5() from running if port 5 is disabled.

Arınç