[PATCH 01/10] dt-bindings: mmc: spacemit,sdhci: add AIB voltage switching registers

Iker Pedrosa
2026-03-02T15:13:51Z

Add SpacemiT K1 AIB register properties for UHS voltage switching
support:

- spacemit,aib-mmc1-io-reg: AIB MMC1 IO register address for voltage
switching
- spacemit,apbc-asfar-reg: APBC ASFAR register address for AIB access
- spacemit,apbc-assar-reg: APBC ASSAR register address for AIB access

These properties enable the driver to perform voltage switching between
3.3V and 1.8V required for UHS SD card modes.

Signed-off-by: Iker Pedrosa <ikerpedrosam@gmail.com>
---
Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml | 15 +++++++++++++++
1 file changed, 15 insertions(+)

diff --git a/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml b/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml
index 13d9382058fbc1c12be1024d1c550f04a825673c..4d6590aa8262009b6e5697a04b45cf3736c0fa42 100644
--- a/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml
+++ b/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml
@@ -32,6 +32,18 @@ properties:
- const: core
- const: io

+ spacemit,aib-mmc1-io-reg:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: AIB MMC1 IO register address for voltage switching
+
+ spacemit,apbc-asfar-reg:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: APBC ASFAR register address for AIB access
+
+ spacemit,apbc-assar-reg:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: APBC ASSAR register address for AIB access
+
required:
- compatible
- reg
@@ -50,4 +62,7 @@ examples:
interrupt-parent = <&plic>;
clocks = <&clk_apmu 10>, <&clk_apmu 13>;
clock-names = "core", "io";
+ spacemit,aib-mmc1-io-reg = <0xd401e81c>;
+ spacemit,apbc-asfar-reg = <0xd4015050>;
+ spacemit,apbc-assar-reg = <0xd4015054>;
};

--
2.53.0