[PATCH v7 1/9] dt-bindings: mmc: spacemit,sdhci: add pinctrl support for voltage switching

Iker Pedrosa
2026-04-13T07:25:22Z

Document pinctrl properties to support voltage-dependent pin
configuration switching for UHS-I SD card modes.

Add optional pinctrl-names property with two states:
- "default": For 3.3V operation with standard drive strength
- "state_uhs": For 1.8V operation with optimized drive strength

These pinctrl states allow the SDHCI driver to coordinate voltage
switching with pin configuration changes, ensuring proper signal
integrity during UHS-I mode transitions.

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 9a055d963a7f..34d202af909f 100644
--- a/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml
+++ b/Documentation/devicetree/bindings/mmc/spacemit,sdhci.yaml
@@ -44,6 +44,18 @@ properties:
- const: axi
- const: sdh

+ pinctrl-names:
+ minItems: 1
+ items:
+ - const: default
+ - const: uhs
+
+ pinctrl-0:
+ description: Default pinctrl state for 3.3V operation
+
+ pinctrl-1:
+ description: Optional pinctrl state for 1.8V UHS operation with "uhs" name
+
required:
- compatible
- reg
@@ -62,4 +74,7 @@ examples:
interrupt-parent = <&plic>;
clocks = <&clk_apmu 10>, <&clk_apmu 13>;
clock-names = "core", "io";
+ pinctrl-names = "default", "uhs";
+ pinctrl-0 = <&sdhci_default_cfg>;
+ pinctrl-1 = <&sdhci_uhs_cfg>;
};

--
2.53.0