Re: [PATCH net-next v6 00/11] net: dsa: realtek: variants to drivers, interfaces to a common module

From: Linus Walleij
Date: Fri Feb 09 2024 - 08:18:10 EST


On Fri, Feb 9, 2024 at 6:04 AM Luiz Angelo Daros de Luca
<luizluca@xxxxxxxxx> wrote:

> The current driver consists of two interface modules (SMI and MDIO) and
> two family/variant modules (RTL8365MB and RTL8366RB). The SMI and MDIO
> modules serve as the platform and MDIO drivers, respectively, calling
> functions from the variant modules. In this setup, one interface module
> can be loaded independently of the other, but both variants must be
> loaded (if not disabled at build time) for any type of interface. This
> approach doesn't scale well, especially with the addition of more switch
> variants (e.g., RTL8366B), leading to loaded but unused modules.
> Additionally, this also seems upside down, as the specific driver code
> normally depends on the more generic functions and not the other way
> around.
>
> Each variant module was converted into real drivers, serving as both a
> platform driver (for switches connected using the SMI interface) and an
> MDIO driver (for MDIO-connected switches). The relationship between the
> variant and interface modules is reversed, with the variant module now
> calling both interface functions (if not disabled at build time). While
> in most devices only one interface is likely used, the interface code is
> significantly smaller than a variant module, consuming fewer resources
> than the previous code. With variant modules now functioning as real
> drivers, compatible strings are published only in a single variant
> module, preventing conflicts.
>
> The patch series introduces a new common module for functions shared by
> both variants. This module also absorbs the two previous interface
> modules, as they would always be loaded anyway.
>
> The series relocates the user MII driver from realtek-smi to rtl83xx. It
> is now used by MDIO-connected switches instead of the generic DSA
> driver. There's a change in how this driver locates the MDIO node. It
> now only searches for a child node named "mdio".
>
> The dsa_switch in realtek_priv->ds is now embedded in the struct. It is
> always in use and avoids dynamic memory allocation.
>
> Testing has been performed with an RTL8367S (rtl8365mb) using MDIO
> interface and an RTL8366RB (rtl8366) with SMI interface.

Tested on my RTL8366RB on a D-Link DIR-685 as well, works like a
charm:
Tested-by: Linus Walleij <linus.walleij@xxxxxxxxxx>

Yours,
Linus Walleij