dts/upstream/Bindings/i2c/nvidia,tegra20-i2c.yaml

# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/i2c/nvidia,tegra20-i2c.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

maintainers:
  - Thierry Reding <thierry.reding@gmail.com>
  - Jon Hunter <jonathanh@nvidia.com>

title: NVIDIA Tegra I2C controller driver

properties:
  compatible:
    oneOf:
      - description: Tegra20 has 4 generic I2C controller. This can support
          master and slave mode of I2C communication. The i2c-tegra driver
          only support master mode of I2C communication. Driver of I2C
          controller is only compatible with "nvidia,tegra20-i2c".
        const: nvidia,tegra20-i2c
      - description: Tegra20 has specific I2C controller called as DVC I2C
          controller. This only support master mode of I2C communication.
          Register interface/offset and interrupts handling are different than
          generic I2C controller. Driver of DVC I2C controller is only
          compatible with "nvidia,tegra20-i2c-dvc".
        const: nvidia,tegra20-i2c-dvc
      - description: |
          Tegra30 has 5 generic I2C controller. This controller is very much
          similar to Tegra20 I2C controller with additional feature: Continue
          Transfer Support. This feature helps to implement M_NO_START as per
          I2C core API transfer flags. Driver of I2C controller is compatible
          with "nvidia,tegra30-i2c" to enable the continue transfer support.
          This is also compatible with "nvidia,tegra20-i2c" without continue
          transfer support.
        items:
          - const: nvidia,tegra30-i2c
          - const: nvidia,tegra20-i2c
      - description: |
          Tegra114 has 5 generic I2C controllers. This controller is very much
          similar to Tegra30 I2C controller with some hardware modification:
            - Tegra30/Tegra20 I2C controller has 2 clock source called div-clk
              and fast-clk. Tegra114 has only one clock source called as
              div-clk and hence clock mechanism is changed in I2C controller.
            - Tegra30/Tegra20 I2C controller has enabled per packet transfer
              by default and there is no way to disable it. Tegra114 has this
              interrupt disable by default and SW need to enable explicitly.
          Due to above changes, Tegra114 I2C driver makes incompatible with
          previous hardware driver. Hence, Tegra114 I2C controller is
          compatible with "nvidia,tegra114-i2c".
        const: nvidia,tegra114-i2c
      - description: |
          Tegra124 has 6 generic I2C controllers. These controllers are very
          similar to those found on Tegra114 but also contain several hardware
          improvements and new registers.
        const: nvidia,tegra124-i2c
      - description: |
          Tegra210 has 6 generic I2C controllers. These controllers are very
          similar to those found on Tegra124.
        items:
          - const: nvidia,tegra210-i2c
          - const: nvidia,tegra124-i2c
      - description: |
          Tegra210 has one I2C controller that is on host1x bus and is part of
          the VE power domain and typically used for camera use-cases. This VI
          I2C controller is mostly compatible with the programming model of
          the regular I2C controllers with a few exceptions. The I2C registers
          start at an offset of 0xc00 (instead of 0), registers are 16 bytes
          apart (rather than 4) and the controller does not support slave
          mode.
        const: nvidia,tegra210-i2c-vi
      - description: |
          Tegra186 has 9 generic I2C controllers, two of which are in the AON
          (always-on) partition of the SoC. All of these controllers are very
          similar to those found on Tegra210.
        const: nvidia,tegra186-i2c
      - description: |
          Tegra194 has 8 generic I2C controllers, two of which are in the AON
          (always-on) partition of the SoC. All of these controllers are very
          similar to those found on Tegra186. However, these controllers have
          support for 64 KiB transactions whereas earlier chips supported no
          more than 4 KiB per transactions.
        const: nvidia,tegra194-i2c

  reg:
    maxItems: 1

  interrupts:
    maxItems: 1

  clocks:
    minItems: 1
    maxItems: 2

  clock-names:
    minItems: 1
    maxItems: 2

  resets:
    items:
      - description: module reset

  reset-names:
    items:
      - const: i2c

  power-domains:
    maxItems: 1

  dmas:
    items:
      - description: DMA channel for the reception FIFO
      - description: DMA channel for the transmission FIFO

  dma-names:
    items:
      - const: rx
      - const: tx

allOf:
  - $ref: /schemas/i2c/i2c-controller.yaml
  - if:
      properties:
        compatible:
          contains:
            enum:
              - nvidia,tegra20-i2c
              - nvidia,tegra30-i2c
    then:
      properties:
        clocks:
          minItems: 2
        clock-names:
          items:
            - const: div-clk
            - const: fast-clk

  - if:
      properties:
        compatible:
          contains:
            enum:
              - nvidia,tegra114-i2c
              - nvidia,tegra210-i2c
    then:
      properties:
        clocks:
          maxItems: 1
        clock-names:
          items:
            - const: div-clk

  - if:
      properties:
        compatible:
          contains:
            const: nvidia,tegra210-i2c-vi
    then:
      properties:
        clocks:
          minItems: 2
        clock-names:
          items:
            - const: div-clk
            - const: slow
        power-domains:
          items:
            - description: phandle to the VENC power domain
    else:
      properties:
        power-domains: false

unevaluatedProperties: false

examples:
  - |
    i2c@7000c000 {
        compatible = "nvidia,tegra20-i2c";
        reg = <0x7000c000 0x100>;
        interrupts = <0 38 0x04>;
        clocks = <&tegra_car 12>, <&tegra_car 124>;
        clock-names = "div-clk", "fast-clk";
        resets = <&tegra_car 12>;
        reset-names = "i2c";
        dmas = <&apbdma 16>, <&apbdma 16>;
        dma-names = "rx", "tx";

        #address-cells = <1>;
        #size-cells = <0>;
    };