Re: [PATCH v4 net-next 01/14] dt-bindings: net: dsa: update the description of 'dsa,member' property

Rob Herring (Arm)
2026-04-08T13:40:49Z

On Tue, 31 Mar 2026 19:30:12 +0800, Wei Fang wrote:
> The current description indicates that the 'dsa,member' property cannot
> be set for a switch that is not part of any cluster. Vladimir thinks
> that this is a case where the actual technical limitation was poorly
> transposed into words when this restriction was first documented, in
> commit 8c5ad1d6179d ("net: dsa: Document new binding").
>
> The true technical limitation is that many DSA tagging protocols are
> topology-unaware, and always call dsa_conduit_find_user() with a
> switch_id of 0. Specifying a custom "dsa,member" property with a
> non-zero switch_id would break them.
>
> Therefore, for topology-aware switches, it is fine to specify this
> property for them, even if they are not part of any cluster. Our NETC
> switch is a good example which is topology-aware, the switch_id is
> carried in the switch tag, but the switch_id 0 is reserved for VEPA
> switch and cannot be used, so we need to use this property to assign
> a non-zero switch_id for it.
>
> Suggested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
> Signed-off-by: Wei Fang <wei.fang@nxp.com>
> ---
> Documentation/devicetree/bindings/net/dsa/dsa.yaml | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>

Acked-by: Rob Herring (Arm) <robh@kernel.org>