[PATCH v2 1/1] dt-bindings: net: ethernet-phy: clarify when compatible must specify PHY ID

Buday Csaba
2025-11-03T08:13:59Z

Change PHY ID description in ethernet-phy.yaml to clarify that a
PHY ID is required (may -> must) when the PHY requires special
initialization sequence.

Link: https://lore.kernel.org/netdev/20251026212026.GA2959311-robh@kernel.org/
Link: https://lore.kernel.org/netdev/aQIZvDt5gooZSTcp@debianbuilder/

Signed-off-by: Buday Csaba <buday.csaba@prolan.hu>
---
V1 -> V2: Changed wording on maintainer request.
---
.../devicetree/bindings/net/ethernet-phy.yaml | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
index 2ec2d9fda..bb4c49fc5 100644
--- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml
+++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
@@ -35,9 +35,13 @@ properties:
description: PHYs that implement IEEE802.3 clause 45
- pattern: "^ethernet-phy-id[a-f0-9]{4}\\.[a-f0-9]{4}$"
description:
- If the PHY reports an incorrect ID (or none at all) then the
- compatible list may contain an entry with the correct PHY ID
- in the above form.
+ PHYs contain identification registers. These will be read to
+ identify the PHY. If the PHY reports an incorrect ID, or the
+ PHY requires a specific initialization sequence (like a
+ particular order of clocks, resets, power supplies), in
+ order to be able to read the ID registers, then the
+ compatible list must contain an entry with the correct PHY
+ ID in the above form.
The first group of digits is the 16 bit Phy Identifier 1
register, this is the chip vendor OUI bits 3:18. The
second group of digits is the Phy Identifier 2 register,

base-commit: 0d0eb186421d0886ac466008235f6d9eedaf918e
--
2.39.5