dt-bindings: pinctrl: rt305x: add proper function muxing binding

Not every function can be muxed to a group. Add proper binding which
documents which function can be muxed to a group or set of groups.
Signed-off-by: Arınç ÜNAL <arinc.unal@arinc9.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Link: https://lore.kernel.org/r/20221231160849.40544-6-arinc.unal@arinc9.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

Documentation/devicetree/bindings/pinctrl/ralink,rt305x-pinctrl.yaml

@@ -30,38 +30,225 @@ patternProperties:
         $ref: pinmux-node.yaml#
 
         properties:
-          groups:
-            description: The pin group to select.
-            enum: [
-              # common
-              i2c, jtag, led, mdio, rgmii, spi, spi_cs1, uartf, uartlite,
-
-              # For RT3050, RT3052 and RT3350 SoCs
-              sdram,
-
-              # For RT3352 SoC
-              lna, pa
-            ]
-
           function:
-            description: The mux function to select.
-            enum: [
-              # common
-              gpio, gpio i2s, gpio uartf, i2c, i2s uartf, jtag, led, mdio,
-              pcm gpio, pcm i2s, pcm uartf, rgmii, spi, spi_cs1, uartf,
-              uartlite, wdg_cs1,
+            description:
+              A string containing the name of the function to mux to the group.
+            anyOf:
+              - description: For RT3050, RT3052 and RT3350 SoCs
+                enum: [gpio, gpio i2s, gpio uartf, i2c, i2s uartf, jtag, mdio,
+                       pcm gpio, pcm i2s, pcm uartf, rgmii, sdram, spi, uartf,
+                       uartlite]
 
-              # For RT3050, RT3052 and RT3350 SoCs
-              sdram,
+              - description: For RT3352 SoC
+                enum: [gpio, gpio i2s, gpio uartf, i2c, i2s uartf, jtag, led,
+                       lna, mdio, pa, pcm gpio, pcm i2s, pcm uartf, rgmii, spi,
+                       spi_cs1, uartf, uartlite, wdg_cs1]
 
-              # For RT3352 SoC
-              lna, pa
-            ]
+              - description: For RT5350 SoC
+                enum: [gpio, gpio i2s, gpio uartf, i2c, i2s uartf, jtag, led,
+                       pcm gpio, pcm i2s, pcm uartf, spi, spi_cs1, uartf,
+                       uartlite, wdg_cs1]
+
+          groups:
+            description:
+              An array of strings. Each string contains the name of a group.
+            maxItems: 1
 
         required:
           - groups
           - function
 
+        allOf:
+          - if:
+              properties:
+                function:
+                  const: gpio
+            then:
+              properties:
+                groups:
+                  anyOf:
+                    - description: For RT3050, RT3052 and RT3350 SoCs
+                      enum: [i2c, jtag, mdio, rgmii, sdram, spi, uartf,
+                             uartlite]
+
+                    - description: For RT3352 SoC
+                      enum: [i2c, jtag, led, lna, mdio, pa, rgmii, spi, spi_cs1,
+                             uartf, uartlite]
+
+                    - description: For RT5350 SoC
+                      enum: [i2c, jtag, led, spi, spi_cs1, uartf, uartlite]
+
+          - if:
+              properties:
+                function:
+                  const: gpio i2s
+            then:
+              properties:
+                groups:
+                  enum: [uartf]
+
+          - if:
+              properties:
+                function:
+                  const: gpio uartf
+            then:
+              properties:
+                groups:
+                  enum: [uartf]
+
+          - if:
+              properties:
+                function:
+                  const: i2c
+            then:
+              properties:
+                groups:
+                  enum: [i2c]
+
+          - if:
+              properties:
+                function:
+                  const: i2s uartf
+            then:
+              properties:
+                groups:
+                  enum: [uartf]
+
+          - if:
+              properties:
+                function:
+                  const: jtag
+            then:
+              properties:
+                groups:
+                  enum: [jtag]
+
+          - if:
+              properties:
+                function:
+                  const: led
+            then:
+              properties:
+                groups:
+                  enum: [led]
+
+          - if:
+              properties:
+                function:
+                  const: lna
+            then:
+              properties:
+                groups:
+                  enum: [lna]
+
+          - if:
+              properties:
+                function:
+                  const: mdio
+            then:
+              properties:
+                groups:
+                  enum: [mdio]
+
+          - if:
+              properties:
+                function:
+                  const: pa
+            then:
+              properties:
+                groups:
+                  enum: [pa]
+
+          - if:
+              properties:
+                function:
+                  const: pcm gpio
+            then:
+              properties:
+                groups:
+                  enum: [uartf]
+
+          - if:
+              properties:
+                function:
+                  const: pcm i2s
+            then:
+              properties:
+                groups:
+                  enum: [uartf]
+
+          - if:
+              properties:
+                function:
+                  const: pcm uartf
+            then:
+              properties:
+                groups:
+                  enum: [uartf]
+
+          - if:
+              properties:
+                function:
+                  const: rgmii
+            then:
+              properties:
+                groups:
+                  enum: [rgmii]
+
+          - if:
+              properties:
+                function:
+                  const: sdram
+            then:
+              properties:
+                groups:
+                  enum: [sdram]
+
+          - if:
+              properties:
+                function:
+                  const: spi
+            then:
+              properties:
+                groups:
+                  enum: [spi]
+
+          - if:
+              properties:
+                function:
+                  const: spi_cs1
+            then:
+              properties:
+                groups:
+                  enum: [spi_cs1]
+
+          - if:
+              properties:
+                function:
+                  const: uartf
+            then:
+              properties:
+                groups:
+                  enum: [uartf]
+
+          - if:
+              properties:
+                function:
+                  const: uartlite
+            then:
+              properties:
+                groups:
+                  enum: [uartlite]
+
+          - if:
+              properties:
+                function:
+                  const: wdg_cs1
+            then:
+              properties:
+                groups:
+                  enum: [spi_cs1]
+
         additionalProperties: false
 
     additionalProperties: false
@@ -75,7 +262,6 @@ required:
 additionalProperties: false
 
 examples:
-  # Pinmux controller node
   - |
     pinctrl {
       compatible = "ralink,rt305x-pinctrl";