[PATCH v1 3/8] dt-bindings: pinctrl: add NXP MC33978/MC34978 pinctrl

[Oleksij Rempel]

Add device tree binding documentation for the pin control and GPIO block
of the NXP MC33978/MC34978 Multiple Switch Detection Interface (MSDI).

This block manages 22 switch detection inputs (14 Switch-to-Ground,
8 Programmable) and acts as a GPIO controller.

Additionally, it supports pin configuration for hardware-specific features
required for long-term contact maintenance in harsh environments, such as
adjusting the continuous/pulsed wetting current to penetrate oxide layers
on mechanical switches.

Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
---
 .../devicetree/bindings/mfd/nxp,mc33978.yaml  | 12 ++++
 .../bindings/pinctrl/nxp,mc33978-pinctrl.yaml | 66 +++++++++++++++++++
 2 files changed, 78 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pinctrl/nxp,mc33978-pinctrl.yaml

diff --git a/Documentation/devicetree/bindings/mfd/nxp,mc33978.yaml b/Documentation/devicetree/bindings/mfd/nxp,mc33978.yaml
index 85720f389509..5e8ab2cff685 100644
--- a/Documentation/devicetree/bindings/mfd/nxp,mc33978.yaml
+++ b/Documentation/devicetree/bindings/mfd/nxp,mc33978.yaml
@@ -52,6 +52,12 @@ properties:
   vbatp-supply:
     description: Battery/power supply
 
+  pinctrl:
+    type: object
+    $ref: /schemas/pinctrl/nxp,mc33978-pinctrl.yaml#
+    description: |
+      Pinctrl and GPIO controller child node for the 22 switch inputs.
+
 required:
   - compatible
   - reg
@@ -82,5 +88,11 @@ examples:
 
             vddq-supply = <&reg_3v3>;
             vbatp-supply = <&reg_12v>;
+
+            pinctrl {
+                compatible = "nxp,mc33978-pinctrl";
+                gpio-controller;
+                #gpio-cells = <2>;
+            };
         };
     };
diff --git a/Documentation/devicetree/bindings/pinctrl/nxp,mc33978-pinctrl.yaml b/Documentation/devicetree/bindings/pinctrl/nxp,mc33978-pinctrl.yaml
new file mode 100644
index 000000000000..4eeb70da6752
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/nxp,mc33978-pinctrl.yaml
@@ -0,0 +1,66 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pinctrl/nxp,mc33978-pinctrl.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NXP MC33978/MC34978 Pinctrl/GPIO Driver
+
+maintainers:
+  - David Jander <david@xxxxxxxxxxx>
+  - Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
+
+description: |
+  Pin control and GPIO driver for the MC33978/MC34978 MSDI device.
+
+  Pin numbering:
+  - Pins 0-13: SG0-SG13 (Switch-to-Ground inputs)
+  - Pins 14-21: SP0-SP7 (Programmable inputs, can be SG or SB)
+
+properties:
+  compatible:
+    enum:
+      - nxp,mc33978-pinctrl
+      - nxp,mc34978-pinctrl
+
+  gpio-controller: true
+
+  '#gpio-cells':
+    const: 2
+
+  ngpios:
+    const: 22
+
+patternProperties:
+  "-grp$":
+    type: object
+    $ref: pincfg-node.yaml#
+    additionalProperties: false
+    description: |
+      Pin configuration subnodes.
+    properties:
+      pins: true
+      bias-pull-up: true
+      bias-pull-down: true
+      bias-high-impedance: true
+
+required:
+  - compatible
+  - gpio-controller
+  - '#gpio-cells'
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    pinctrl {
+        compatible = "nxp,mc33978-pinctrl";
+        gpio-controller;
+        #gpio-cells = <2>;
+        ngpios = <22>;
+
+        door-grp {
+            pins = "sg0";
+            bias-high-impedance;
+        };
+    };
-- 
2.47.3