[PATCH v3] dt-bindings: mfd: Add Renesas R2A11302FT PMIC

[Wolfram Sang <wsa+renesas@sang-engineering.com>]

This PMIC is referenced in upstream DTs for the Renesas Lager and
Koelsch boards. Sadly, there is no documentation available. This minimal
binding description states the facts that we do know.

Fixes:
arch/arm/boot/dts/renesas/r8a7790-lager.dtb: /soc/spi@e6e10000/pmic@0: failed to match any schema with compatible: ['renesas,r2a11302ft']
arch/arm/boot/dts/renesas/r8a7791-koelsch.dtb: /soc/spi@e6e20000/pmic@0: failed to match any schema with compatible: ['renesas,r2a11302ft']

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---

Changes since last version:
* switched to b4-style patch version counting
* added unevaluatedProperties
* fixed whitespaces in example
* added description stating that the binding is incomplete
* reworded commit message to state the reason for incompleteness

Thanks Krzysztof for all the input!

 .../bindings/mfd/renesas,r2a11302ft.yaml      | 58 +++++++++++++++++++
 1 file changed, 58 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mfd/renesas,r2a11302ft.yaml

diff --git a/Documentation/devicetree/bindings/mfd/renesas,r2a11302ft.yaml b/Documentation/devicetree/bindings/mfd/renesas,r2a11302ft.yaml
new file mode 100644
index 000000000000..7b96619ebd8c
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/renesas,r2a11302ft.yaml
@@ -0,0 +1,58 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mfd/renesas,r2a11302ft.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Renesas R2A11302FT Power Supply ICs for R-Car
+
+maintainers:
+  - Wolfram Sang <wsa+renesas@sang-engineering.com>
+
+description: |
+  The Renesas R2A11302FT PMIC is used with Renesas R-Car Gen1/Gen2
+  based SoCs.
+
+  FIXME: The binding is incomplete and resembles the information gathered
+  so far.
+
+properties:
+  compatible:
+    const: renesas,r2a11302ft
+
+  reg:
+    maxItems: 1
+
+  spi-max-frequency:
+    maximum: 6000000
+
+  spi-cpol: true
+
+  spi-cpha: true
+
+required:
+  - compatible
+  - reg
+  - spi-cpol
+  - spi-cpha
+
+allOf:
+  - $ref: /schemas/spi/spi-peripheral-props.yaml#
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        pmic@0 {
+            compatible = "renesas,r2a11302ft";
+            reg = <0>;
+            spi-max-frequency = <6000000>;
+            spi-cpol;
+            spi-cpha;
+        };
+    };
+...
-- 
2.47.2