Hi Wells Lu,

thanks for your patch!

On Wed, Oct 27, 2021 at 10:55 AM Wells Lu [off-list ref] wrote:

+      properties:
+        pins:
+          description: |
+            Define pins which are used by pinctrl node's client device.
+
+            It consists of one or more integers which represents the config
+            setting for corresponding pin. Please use macro SPPCTL_IOPAD to
+            define the integers for pins.
+
+            The first argument of the macro is pin number, the second is pin
+            type, the third is type of GPIO, the last is default output state
+            of GPIO.
+          $ref: /schemas/types.yaml#/definitions/uint32-array
+
+        function:
+          description: |
+            Define pin-function which is used by pinctrl node's client device.
+            The name should be one of string in the following enumeration.
+          $ref: "/schemas/types.yaml#/definitions/string"
+          enum: [ SPI_FLASH, SPI_FLASH_4BIT, SPI_NAND, CARD0_EMMC, SD_CARD,
+                  UA0, FPGA_IFX, HDMI_TX, LCDIF, USB0_OTG, USB1_OTG ]
+
+        groups:
+          description: |
+            Define pin-group in a specified pin-function.
+            The name should be one of string in the following enumeration.
+          $ref: "/schemas/types.yaml#/definitions/string"
+          enum: [ SPI_FLASH1, SPI_FLASH2, SPI_FLASH_4BIT1, SPI_FLASH_4BIT2,
+                  SPI_NAND, CARD0_EMMC, SD_CARD, UA0, FPGA_IFX, HDMI_TX1,
+                  HDMI_TX2, HDMI_TX3, LCDIF, USB0_OTG, USB1_OTG ]

Is it possible to use
Documentation/devicetree/bindings/pinctrl/pinmux-node.yaml
for this like other drivers do?

+        zero_func:
+          description: |
+            Disabled pins which are not used by pinctrl node's client device.
+          $ref: /schemas/types.yaml#/definitions/uint32-array

I have never seen this before. Can't you just use pin control hogs
for this so the pin controller just take care of these pins?

+      allOf:
+        - if:
+            properties:
+              function:
+                enum:
+                  - SPI_FLASH
+          then:
+            properties:
+              groups:
+                enum:
+                  - SPI_FLASH1
+                  - SPI_FLASH2
+        - if:
+            properties:
+              function:
+                enum:
+                  - SPI_FLASH_4BIT
+          then:
+            properties:
+              groups:
+                enum:
+                  - SPI_FLASH_4BIT1
+                  - SPI_FLASH_4BIT2
+        - if:
+            properties:
+              function:
+                enum:
+                  - SPI_NAND
+          then:
+            properties:
+              groups:
+                enum:
+                  - SPI_NAND
+        - if:
+            properties:
+              function:
+                enum:
+                  - CARD0_EMMC
+          then:
+            properties:
+              groups:
+                enum:
+                  - CARD0_EMMC
+        - if:
+            properties:
+              function:
+                enum:
+                  - SD_CARD
+          then:
+            properties:
+              groups:
+                enum:
+                  - SD_CARD
+        - if:
+            properties:
+              function:
+                enum:
+                  - UA0
+          then:
+            properties:
+              groups:
+                enum:
+                  - UA0
+        - if:
+            properties:
+              function:
+                enum:
+                  - FPGA_IFX
+          then:
+            properties:
+              groups:
+                enum:
+                  - FPGA_IFX
+        - if:
+            properties:
+              function:
+                enum:
+                  - HDMI_TX
+          then:
+            properties:
+              groups:
+                enum:
+                  - HDMI_TX1
+                  - HDMI_TX2
+                  - HDMI_TX3
+        - if:
+            properties:
+              function:
+                enum:
+                  - LCDIF
+          then:
+            properties:
+              groups:
+                enum:
+                  - LCDIF
+        - if:
+            properties:
+              function:
+                enum:
+                  - USB0_OTG
+          then:
+            properties:
+              groups:
+                enum:
+                  - USB0_OTG
+        - if:
+            properties:
+              function:
+                enum:
+                  - USB1_OTG
+          then:
+            properties:
+              groups:
+                enum:
+                  - USB1_OTG

This looks complex to me, I need feedback from bindings people
on this.

+        pins_uart0: pins_uart0 {
+            function = "UA0";
+            groups = "UA0";
+        };
+
+        pins_uart1: pins_uart1 {
+            pins = <
+                SPPCTL_IOPAD(11,SPPCTL_PCTL_G_PMUX,MUXF_UA1_TX,0)
+                SPPCTL_IOPAD(10,SPPCTL_PCTL_G_PMUX,MUXF_UA1_RX,0)
+                SPPCTL_IOPAD(7,SPPCTL_PCTL_G_GPIO,0,SPPCTL_PCTL_L_OUT)
+            >;
+        };

This first looks like two ways to do the same thing?
UART0 uses strings for group + function and uart1 control
individual pins.

Is it possible to just do it one way?

I think the pins = <...> scheme includes also multiplexing settings
and then it should be named pinmux = <...>:

Please read
Documentation/devicetree/bindings/pinctrl/pinmux-node.yaml
closely.

Yours,
Linus Walleij