From e0c78fcad2bb04651af2ad40ed20714501931d7a Mon Sep 17 00:00:00 2001 From: Buday Csaba Date: Mon, 3 Nov 2025 09:13:42 +0100 Subject: [PATCH] dt-bindings: net: ethernet-phy: clarify when compatible must specify PHY ID 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 Acked-by: Conor Dooley Reviewed-by: Andrew Lunn Reviewed-by: Florian Fainelli Link: https://patch.msgid.link/64c52d1a726944a68a308355433e8ef0f82c4240.1762157515.git.buday.csaba@prolan.hu Signed-off-by: Jakub Kicinski --- .../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 2ec2d9fda7e30..bb4c49fc5fd88 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, -- 2.47.3