Re: [PATCH net-next v2 6/7] net: dsa: mt7530: do not set priv->p5_interface on mt7530_setup_port5()

[Arınç ÜNAL]

On 4.01.2024 18:42, Vladimir Oltean wrote:
> On Wed, Dec 27, 2023 at 07:43:46AM +0300, Arınç ÜNAL wrote:
> > priv->p5_interface and priv->p6_interface are for use on the MT7531 switch.
> > They prevent the CPU ports of MT7531 to be configured again. They are
> > useless for MT7530. Therefore, remove setting priv->p5_interface for
> > MT7530.
> >
> > Signed-off-by: Arınç ÜNAL <arinc.unal@xxxxxxxxxx>
> > ---
>
> What makes priv->p5_interface and priv->p6_interface useless for MT7530
> as you say? This code in mt753x_phylink_mac_config() seems executed
> regardless of switch family:
>
> 	case 5:
> 		if (priv->p5_interface == state->interface)
> 			break;
>
> 		if (mt753x_mac_config(ds, port, mode, state) < 0)
> 			goto unsupported;
>
> 		if (priv->p5_intf_sel != P5_DISABLED)
> 			priv->p5_interface = state->interface;
> 		break;
> 	case 6:
> 		if (priv->p6_interface == state->interface)
> 			break;
>
> 		mt753x_pad_setup(ds, state);
>
> 		if (mt753x_mac_config(ds, port, mode, state) < 0)
> 			goto unsupported;
>
> 		priv->p6_interface = state->interface;
> 		break;

This is also useless for non-MT7531 switches in the sense that it
unnecessarily prevents port 5 and 6 from being reconfigured. There's
nothing wrong with configuring them multiple times. These are the remains
of before phylink was implemented on this driver so the thought of changing
phy_interface_t on the fly was non existent. At that time, it was probably
made to apply to all switch models for convenience, as port 5 and 6 are CPU
ports so they're highly likely to be fixed links.

The reason I don't deal with this code block now is because I will get rid
of priv->p5_interface and priv->p6_interface when I also get rid of
priv->info->cpu_port_config() with a later patch.

Arınç