Re: [PATCH v2 2/3] dt-bindings: pinctrl: mt8192: add binding document

[Rob Herring <robh@xxxxxxxxxx>]

On Sat, Aug 01, 2020 at 12:33:02PM +0800, Zhiyong Tao wrote:
> The commit adds mt8192 compatible node in binding document.
> 
> Signed-off-by: Zhiyong Tao <zhiyong.tao@xxxxxxxxxxxx>
> ---
>  .../bindings/pinctrl/pinctrl-mt8192.yaml      | 175 ++++++++++++++++++
>  1 file changed, 175 insertions(+)
>  create mode 100755 Documentation/devicetree/bindings/pinctrl/pinctrl-mt8192.yaml
> 
> diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8192.yaml b/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8192.yaml
> new file mode 100755
> index 000000000000..88e18e2e23a0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8192.yaml
> @@ -0,0 +1,175 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/pinctrl/pinctrl-mt8192.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Mediatek MT8192 Pin Controller
> +
> +maintainers:
> +  - Sean Wang <sean.wang@xxxxxxxxxxxx>
> +
> +description: |
> +  The Mediatek's Pin controller is used to control SoC pins.
> +
> +properties:
> +  compatible:
> +    const: mediatek,mt8192-pinctrl
> +
> +  gpio-controller: true
> +
> +  '#gpio-cells':
> +    description: |
> +      Number of cells in GPIO specifier. Since the generic GPIO binding is used,
> +      the amount of cells must be specified as 2. See the below
> +      mentioned gpio binding representation for description of particular cells.
> +    const: 2
> +
> +  gpio-ranges:
> +    description: gpio valid number range.
> +    maxItems: 1
> +
> +  reg:
> +    description: |
> +      Physical address base for gpio base registers. There are 11 GPIO
> +      physical address base in mt8192.
> +    maxItems: 11
> +
> +  reg-names:
> +    description: |
> +      Gpio base register names.
> +    maxItems: 11
> +
> +  interrupt-controller: true
> +
> +  '#interrupt-cells':
> +    const: 2
> +
> +  interrupts:
> +    description: The interrupt outputs to sysirq.
> +    maxItems: 1
> +
> +#PIN CONFIGURATION NODES
> +patternProperties:
> +  '^pins':
> +    type: object
> +    description: |
> +      A pinctrl node should contain at least one subnodes representing the
> +      pinctrl groups available on the machine. Each subnode will list the
> +      pins it needs, and how they should be configured, with regard to muxer
> +      configuration, pullups, drive strength, input enable/disable and
> +      input schmitt.
> +      An example of using macro:
> +      node {

'node' doesn't match '^pins' regex.

Better to put an example in the actual example so it is checked.

> +        pinmux = <PIN_NUMBER_PINMUX>;
> +        GENERIC_PINCONFIG;
> +      };
> +    properties:
> +      pinmux:
> +        $ref: "/schemas/types.yaml#/definitions/uint32-array"

Already a common definition in pinmux-node.yaml. Reference that file in 
'^pins'.

> +        description: |
> +          Integer array, represents gpio pin number and mux setting.
> +          Supported pin number and mux varies for different SoCs, and are defined
> +          as macros in dt-bindings/pinctrl/<soc>-pinfunc.h directly.
> +
> +      GENERIC_PINCONFIG:

That's not a property name.

> +        description: |
> +          It is the generic pinconfig options to use, bias-disable,
> +          bias-pull-down, bias-pull-up, input-enable, input-disable, output-low,
> +          output-high, input-schmitt-enable, input-schmitt-disable
> +          and drive-strength are valid.
> +
> +          Some special pins have extra pull up strength, there are R0 and R1 pull-up
> +          resistors available, but for user, it's only need to set R1R0 as 00, 01,
> +          10 or 11. So It needs config "mediatek,pull-up-adv" or
> +          "mediatek,pull-down-adv" to support arguments for those special pins.
> +          Valid arguments are from 0 to 3.
> +
> +          We can use "mediatek,tdsel" which is an integer describing the steps for
> +          output level shifter duty cycle when asserted (high pulse width adjustment).
> +          Valid arguments  are from 0 to 15.
> +          We can use "mediatek,rdsel" which is an integer describing the steps for
> +          input level shifter duty cycle when asserted (high pulse width adjustment).
> +          Valid arguments are from 0 to 63.
> +
> +          When config drive-strength, it can support some arguments, such as
> +          MTK_DRIVE_4mA, MTK_DRIVE_6mA, etc. See dt-bindings/pinctrl/mt65xx.h.
> +          It can only support 2/4/6/8/10/12/14/16mA in mt8192.
> +          For I2C pins, there are existing generic driving setup and the specific
> +          driving setup. I2C pins can only support 2/4/6/8/10/12/14/16mA driving
> +          adjustment in generic driving setup. But in specific driving setup,
> +          they can support 0.125/0.25/0.5/1mA adjustment. If we enable specific
> +          driving setup for I2C pins, the existing generic driving setup will be
> +          disabled. For some special features, we need the I2C pins specific
> +          driving setup. The specific driving setup is controlled by E1E0EN.
> +          So we need add extra vendor driving preperty instead of
> +          the generic driving property.
> +          We can add "mediatek,drive-strength-adv = <XXX>;" to describe the specific
> +          driving setup property. "XXX" means the value of E1E0EN. EN is 0 or 1.
> +          It is used to enable or disable the specific driving setup.
> +          E1E0 is used to describe the detail strength specification of the I2C pin.
> +          When E1=0/E0=0, the strength is 0.125mA.
> +          When E1=0/E0=1, the strength is 0.25mA.
> +          When E1=1/E0=0, the strength is 0.5mA.
> +          When E1=1/E0=1, the strength is 1mA.
> +          So the valid arguments of "mediatek,drive-strength-adv" are from 0 to 7.
> +
> +      bias-pull-down: true
> +
> +      bias-pull-up: true
> +
> +      bias-disable: true
> +
> +      output-high: true
> +
> +      output-low: true
> +
> +      input-enable: true
> +
> +      input-disable: true
> +
> +      input-schmitt-enable: true
> +
> +      input-schmitt-disable: true
> +
> +    required:
> +      - pinmux
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - interrupt-controller
> +  - '#interrupt-cells'
> +  - gpio-controller
> +  - '#gpio-cells'
> +  - gpio-ranges

additionalProperties: false

> +
> +examples:
> +  - |
> +            #include <dt-bindings/pinctrl/mt8192-pinfunc.h>
> +            #include <dt-bindings/interrupt-controller/arm-gic.h>
> +            pio: pinctrl@10005000 {
> +                    compatible = "mediatek,mt8192-pinctrl";
> +                    reg = <0 0x10005000 0 0x1000>,
> +                          <0 0x11c20000 0 0x1000>,
> +                          <0 0x11d10000 0 0x1000>,
> +                          <0 0x11d30000 0 0x1000>,
> +                          <0 0x11d40000 0 0x1000>,
> +                          <0 0x11e20000 0 0x1000>,
> +                          <0 0x11e70000 0 0x1000>,
> +                          <0 0x11ea0000 0 0x1000>,
> +                          <0 0x11f20000 0 0x1000>,
> +                          <0 0x11f30000 0 0x1000>,
> +                          <0 0x1000b000 0 0x1000>;
> +                    reg-names = "iocfg0", "iocfg_rm", "iocfg_bm",
> +                          "iocfg_bl", "iocfg_br", "iocfg_lm",
> +                          "iocfg_lb", "iocfg_rt", "iocfg_lt",
> +                          "iocfg_tl", "eint";
> +                    gpio-controller;
> +                    #gpio-cells = <2>;
> +                    gpio-ranges = <&pio 0 0 220>;
> +                    interrupt-controller;
> +                    interrupts = <GIC_SPI 212 IRQ_TYPE_LEVEL_HIGH 0>;
> +                    #interrupt-cells = <2>;
> +            };
> -- 
> 2.18.0