Re: [PATCH net-next v4 00/11] net: dsa: realtek: MDIO interface and RTL8367S

Luiz Angelo Daros de Luca
2022-01-20T17:47:10Z

> On Wed, Jan 05, 2022 at 12:15:04AM -0300, Luiz Angelo Daros de Luca wrote:
> > The old realtek-smi driver was linking subdrivers into a single
> > realtek-smi.ko After this series, each subdriver will be an independent
> > module required by either realtek-smi (platform driver) or the new
> > realtek-mdio (mdio driver). Both interface drivers (SMI or MDIO) are
> > independent, and they might even work side-by-side, although it will be
> > difficult to find such device. The subdriver can be individually
> > selected but only at buildtime, saving some storage space for custom
> > embedded systems.
> >
> > Existing realtek-smi devices continue to work untouched during the
> > tests. The realtek-smi was moved into a realtek subdirectory, but it
> > normally does not break things.
> >
> > I couldn't identify a fixed relation between port numbers (0..9) and
> > external interfaces (0..2), and I'm not sure if it is fixed for each
> > chip version or a device configuration. Until there is more info about
> > it, there is a new port property "realtek,ext-int" that can inform the
> > external interface.
>
> Generally it isn't a good idea to put in the device tree things that you
> don't understand. The reason being that you'd have to support those
> device tree bindings even when you do understand those things. A device
> tree blob has a separate lifetime compared to the kernel image, so a new
> kernel image would have to support the device trees in circulation which
> have this realtek,ext-int property.
>
> Can you use a fixed relationship between the port number and the
> external interface in the driver, until it is proven that this info
> cannot be known statically or by reading some device configuration?

Thanks, Vladimir. OK. I'll make it automatically defined. I dug again
into the realtek driver and I might be able to remove that property.
There are just a couple of situations that I might select based on
chip_id/version.

BTW, Should I split the series in two, submitting the already consensus patch?

Luiz