Re: Aw: Re: [PATCH 4/5] arm: dts: mt7623: mux phy0 on Bananapi BPI-R2

[Arınç ÜNAL]

On 31.01.2023 19:39, Frank Wunderlich wrote:
> Hi
> > Gesendet: Dienstag, 31. Januar 2023 um 12:55 Uhr
> > Von: "Matthias Brugger" <matthias.bgg@xxxxxxxxx>
> > An: "Arınç ÜNAL" <arinc.unal@xxxxxxxxxx>, frank-w@xxxxxxxxxxxxxxx, "Rob Herring" <robh+dt@xxxxxxxxxx>, "Krzysztof Kozlowski" <krzysztof.kozlowski+dt@xxxxxxxxxx>
> > Cc: devicetree@xxxxxxxxxxxxxxx, linux-arm-kernel@xxxxxxxxxxxxxxxxxxx, linux-mediatek@xxxxxxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx, erkin.bozoglu@xxxxxxxxxx, "Sean Wang" <sean.wang@xxxxxxxxxxxx>, "DENG Qingfang" <dqfext@xxxxxxxxx>
> > Betreff: Re: [PATCH 4/5] arm: dts: mt7623: mux phy0 on Bananapi BPI-R2
> >
> >
> >
> > On 25/01/2023 17:54, Arınç ÜNAL wrote:
> > > On 25.01.2023 19:41, Frank Wunderlich wrote:
> > > > Am 20. Januar 2023 21:53:17 MEZ schrieb "Arınç ÜNAL" <arinc.unal@xxxxxxxxxx>:
> > > >
> > > > >          switch@1f {
> > > > >              compatible = "mediatek,mt7530";
> > > > >              reg = <0x1f>;
> > > > > @@ -199,11 +208,6 @@ ports {
> > > > >                  #address-cells = <1>;
> > > > >                  #size-cells = <0>;
> > > > >
> > > > > -                port@0 {
> > > > > -                    reg = <0>;
> > > > > -                    label = "wan";
> > > > > -                };
> > > > > -
> > > >
> > > > This will break existing userspace setups using wan as interface name.
> > >
> > > Yup. The OS being used will have to either rename the interface or adapt to the
> > > new name, eth1.
> >
> > In that case please explain in the commit message why this is needed. We are
> > trying really hard to not break userspace by a device-tree update.
>
> I understand the reason why Arınç wants to change it:
>
> currently all ports including wan-port are routed via dsa over gmac0 (trgmii), Arınç enables the second gmac and port5 of switch to route wan-traffic over the other gmac. But unfortunately there is no mainline-way to rename the gmac1 interface (eth1) to wan...this would be a way to not break the userspace.
>
> i had an older patch for mtk_eth_soc [1] which do it at driver level for mediatek ethernet driver, but afair a generic way to (re)name interfaces in dts (vendor independ) was requested as the right way.
>
> regards Frank
>
> [1] https://github.com/frank-w/BPI-Router-Linux/commit/5088c9c81e90014622a950fca38cfb29e0421155

I tried this [0] before. It's not going to happen on mainline, and 
that's fine. I'll just clearly mention on the patch log that the 
interface name will change with this patch.

[0] 
https://lore.kernel.org/netdev/20220404114000.3549-1-arinc.unal@xxxxxxxxxx/t/#u

Arınç