[PATCH v2 1/5] dt-bindings: pinctrl: add the NXP LX2160A RCW pad mux

[Vincent Jardin via B4 Relay]

From: Vincent Jardin <vjardin at free.fr>

The LX2160A muxes its IIC, XSPI, SDHC, UART, IRQ and EVT pads from
fields of the RCW: read-only in RCWSR12..14 of DCFG, changed at runtime
through the override registers of its DCSR view.

Describe the pad mux as a node without registers, a child of DCFG: one
group per RCW field, one function per encoding.

Each function lists the groups that take it, so a pair the driver
would refuse, such as can on iic1, is refused by the schema.

Signed-off-by: Vincent Jardin <vjardin at free.fr>
---
 .../bindings/pinctrl/fsl,lx2160a-rcw-pinmux.yaml   | 262 +++++++++++++++++++++
 1 file changed, 262 insertions(+)

diff --git a/Documentation/devicetree/bindings/pinctrl/fsl,lx2160a-rcw-pinmux.yaml b/Documentation/devicetree/bindings/pinctrl/fsl,lx2160a-rcw-pinmux.yaml
new file mode 100644
index 000000000000..b1ccd153a43b
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/fsl,lx2160a-rcw-pinmux.yaml
@@ -0,0 +1,262 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pinctrl/fsl,lx2160a-rcw-pinmux.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NXP LX2160A RCW pad muxes
+
+maintainers:
+  - Vincent Jardin <vjardin at free.fr>
+
+description:
+  The LX2160A muxes its IIC, XSPI, SDHC, UART, IRQ and EVT pads based on its
+  RCW. The related fields are from the read-only RCWSR12 to RCWSR14 registers
+  of DCFG, and changed at runtime by writing the RCW override registers in
+  the DCSR view of DCFG. The node is a child of the DCFG node, which owns both
+  views, and needs no registers of its own. A pad group is one field, named
+  from its pads, and takes the functions its field encodes, gpio on every
+  group and the others per function below, as the RCW chapter of the
+  reference manual lists them (the *_PMUX fields). A board selects a state
+  of its own with the usual pinctrl-0 on this node, a hog.
+
+properties:
+  compatible:
+    const: fsl,lx2160a-rcw-pinmux
+
+patternProperties:
+  '-pins$':
+    type: object
+    $ref: pinmux-node.yaml#
+    additionalProperties: false
+
+    properties:
+      function:
+        enum: [ asleep, can, evt, flexspi, flextimer, gpio, i2c, irq,
+                reset-req, sdhc, sdhc-clk, sdhc-data, sdhc-data4, sdhc-spi,
+                spi, uart, uart3, uart4 ]
+
+      groups:
+        items:
+          enum: [ iic1, iic2, iic3, iic4, iic5, iic6, xspi1-data74,
+                  xspi1-data30, xspi1-base, sdhc1-base, sdhc1-dir,
+                  sdhc2-data74, sdhc2-base, uart1-soutsin, uart1-rtscts,
+                  uart2-soutsin, uart2-rtscts, irq11-8, irq7-4, irq3-0,
+                  evt4-3, evt2-0, clk-out, asleep, reset-req ]
+
+    required:
+      - function
+      - groups
+
+    allOf:
+      - if:
+          properties:
+            function:
+              const: asleep
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ asleep ]
+
+      - if:
+          properties:
+            function:
+              const: can
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ iic3, iic4 ]
+
+      - if:
+          properties:
+            function:
+              const: evt
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ iic3, iic4, evt4-3, evt2-0, asleep ]
+
+      - if:
+          properties:
+            function:
+              const: flexspi
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ xspi1-data74, xspi1-data30, xspi1-base,
+                        sdhc2-data74, sdhc2-base ]
+
+      - if:
+          properties:
+            function:
+              const: flextimer
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ iic2, irq7-4, irq3-0, evt4-3, evt2-0, clk-out ]
+
+      - if:
+          properties:
+            function:
+              const: gpio
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ iic2, iic3, iic4, iic5, iic6, xspi1-data74,
+                        xspi1-data30, xspi1-base, sdhc1-base, sdhc1-dir,
+                        sdhc2-data74, sdhc2-base, uart1-soutsin,
+                        uart1-rtscts, uart2-soutsin, uart2-rtscts,
+                        irq11-8, irq7-4, irq3-0, evt4-3, evt2-0, clk-out,
+                        asleep, reset-req, iic1 ]
+
+      - if:
+          properties:
+            function:
+              const: i2c
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ iic2, iic3, iic4, iic5, iic6, sdhc2-data74, iic1 ]
+
+      - if:
+          properties:
+            function:
+              const: irq
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ irq11-8, irq7-4, irq3-0 ]
+
+      - if:
+          properties:
+            function:
+              const: reset-req
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ reset-req ]
+
+      - if:
+          properties:
+            function:
+              const: sdhc
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ iic2, sdhc1-base, sdhc1-dir, sdhc2-data74,
+                        sdhc2-base ]
+
+      - if:
+          properties:
+            function:
+              const: sdhc-clk
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ iic5, iic6 ]
+
+      - if:
+          properties:
+            function:
+              const: sdhc-data
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ sdhc1-dir ]
+
+      - if:
+          properties:
+            function:
+              const: sdhc-data4
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ sdhc1-base ]
+
+      - if:
+          properties:
+            function:
+              const: sdhc-spi
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ sdhc1-base ]
+
+      - if:
+          properties:
+            function:
+              const: spi
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ iic5, sdhc1-base, sdhc1-dir, sdhc2-base ]
+
+      - if:
+          properties:
+            function:
+              const: uart
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ uart1-soutsin, uart1-rtscts, uart2-soutsin,
+                        uart2-rtscts ]
+
+      - if:
+          properties:
+            function:
+              const: uart3
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ uart1-rtscts ]
+
+      - if:
+          properties:
+            function:
+              const: uart4
+        then:
+          properties:
+            groups:
+              items:
+                enum: [ uart2-rtscts ]
+
+required:
+  - compatible
+
+allOf:
+  - $ref: pinctrl.yaml#
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    pinctrl {
+        compatible = "fsl,lx2160a-rcw-pinmux";
+
+        iic3-i2c-pins {
+            function = "i2c";
+            groups = "iic3";
+        };
+
+        iic3-gpio-pins {
+            function = "gpio";
+            groups = "iic3";
+        };
+    };

-- 
2.43.0