Though isn't described in existing devicetrees, most Rockchip combphys
belong to a specific power-domain of the SoC. Taking RK3588 as example,
combphy 0 and combphy 2 belong to the PD_BUS domain. Document the
power-domains property to allow describing the information correctly
in devicetree.

Signed-off-by: Yao Zi <ziyao@disroot.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
---
 .../devicetree/bindings/phy/phy-rockchip-naneng-combphy.yaml   | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Documentation/devicetree/bindings/phy/phy-rockchip-naneng-combphy.yaml b/Documentation/devicetree/bindings/phy/phy-rockchip-naneng-combphy.yaml
index 3e101c3c5ea9..db293d2fbf1a 100644
--- a/Documentation/devicetree/bindings/phy/phy-rockchip-naneng-combphy.yaml
+++ b/Documentation/devicetree/bindings/phy/phy-rockchip-naneng-combphy.yaml
@@ -45,6 +45,9 @@ properties:
   phy-supply:
     description: Single PHY regulator
 
+  power-domains:
+    maxItems: 1
+
   rockchip,enable-ssc:
     type: boolean
     description:
-- 
2.50.1