[PATCH 1/2] dt-bindings: rtc: nct3018y: add nuvoton,ctrl-reg-val property

From: David Wang

Date: Thu Apr 09 2026 - 03:22:35 EST


Add "nuvoton,ctrl-reg-val" vendor property to allow optional
initialization of the RTC control register (0x0A).

This allows platform-specific configurations like 24h mode and
write ownership to be defined via Device Tree.

Signed-off-by: David Wang <tomato1220@xxxxxxxxx>
---
Documentation/devicetree/bindings/rtc/nuvoton,nct3018y.yaml | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/Documentation/devicetree/bindings/rtc/nuvoton,nct3018y.yaml b/Documentation/devicetree/bindings/rtc/nuvoton,nct3018y.yaml
index 4f9b5604acd9..0984dfb77170 100644
--- a/Documentation/devicetree/bindings/rtc/nuvoton,nct3018y.yaml
+++ b/Documentation/devicetree/bindings/rtc/nuvoton,nct3018y.yaml
@@ -24,6 +24,10 @@ properties:

reset-source: true

+ nuvoton,ctrl-reg-val:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: Initial value for the control register (0x0A).
+
required:
- compatible
- reg
@@ -39,6 +43,7 @@ examples:
rtc@6f {
compatible = "nuvoton,nct3018y";
reg = <0x6f>;
+ nuvoton,ctrl-reg-val = <0x21>;
};
};

--
2.34.1