Re: [PATCH net-next 08/11] net: dsa: rzn1-a5psw: Make DSA tag protocol configurable via OF data

Vladimir Oltean
2025-11-21T20:55:51Z

On Fri, Nov 21, 2025 at 11:35:34AM +0000, Prabhakar wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> Update the RZN1 A5PSW driver to obtain the DSA tag protocol from
> device-specific data instead of using a hard-coded value. Add a new
> `tag_proto` field to `struct a5psw_of_data` and use it in
> `a5psw_get_tag_protocol()` to return the appropriate protocol for
> each SoC.
>
> This allows future SoCs such as RZ/T2H and RZ/N2H, which use the
> DSA_TAG_PROTO_RZT2H_ETHSW tag format, to share the same driver
> infrastructure without code duplication.

Again the twitching when reading the commit title. I thought this has
something to do with the "dsa-tag-protocol" property from
Documentation/devicetree/bindings/net/dsa/dsa-port.yaml. The tagger *is*
runtime-configurable if you implement the ds->ops->change_tag_protocol()
API, and it's also possible to trigger that API function from OF
properties. But this is not what the patch does, so it is confusing.

I think it would be more natural to say "choose tagging protocol based
on compatible string".

> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> ---

Anyway I'm not reviewing this commit until the reason why you added a
new name for this tagger becomes completely clear.