[PATCH v2 3/4] dt-bindings: net: mdio: add phy-id-read-needs-reset property

From: Buday Csaba

Date: Wed Oct 15 2025 - 09:45:10 EST


Some Ethernet PHYs require a hard reset before accessing their MDIO
registers. When the ID is not provided by a compatible string,
reading the PHY ID may fail on such devices.

This patch introduces a new device tree property called
`phy-id-read-needs-reset`, which can be used to hard reset the
PHY before attempting to read its ID via MDIO.

Signed-off-by: Buday Csaba <buday.csaba@xxxxxxxxx>
---
Documentation/devicetree/bindings/net/ethernet-phy.yaml | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
index 2ec2d9fda..b570f8038 100644
--- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml
+++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
@@ -215,6 +215,14 @@ properties:
Delay after the reset was deasserted in microseconds. If
this property is missing the delay will be skipped.

+ phy-id-read-needs-reset:
+ $ref: /schemas/types.yaml#/definitions/flag
+ description:
+ Some PHYs require a hard reset before accessing MDIO registers.
+ This workaround allows auto-detection of the PHY ID in such cases.
+ When the PHY ID is provided with the 'compatible' string, setting
+ this property has no effect.
+
sfp:
$ref: /schemas/types.yaml#/definitions/phandle
description:
--
2.39.5