linux/Documentation/devicetree/bindings/dma/ingenic,dma.yaml

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

title: Ingenic SoCs DMA Controller

maintainers:
  - Paul Cercueil <paul@crapouillou.net>

allOf:
  - $ref: dma-controller.yaml#

properties:
  compatible:
    oneOf:
      - enum:
          - ingenic,jz4740-dma
          - ingenic,jz4725b-dma
          - ingenic,jz4755-dma
          - ingenic,jz4760-dma
          - ingenic,jz4760-bdma
          - ingenic,jz4760-mdma
          - ingenic,jz4760b-dma
          - ingenic,jz4760b-bdma
          - ingenic,jz4760b-mdma
          - ingenic,jz4770-dma
          - ingenic,jz4780-dma
          - ingenic,x1000-dma
          - ingenic,x1830-dma
      - items:
          - const: ingenic,jz4770-bdma
          - const: ingenic,jz4760b-bdma

  reg:
    items:
      - description: Channel-specific registers
      - description: System control registers

  interrupts:
    maxItems: 1

  clocks:
    maxItems: 1

  "#dma-cells":
    enum: [2, 3]
    description: >
      DMA clients must use the format described in dma.txt, giving a phandle
      to the DMA controller plus the following integer cells:

      - Request type: The DMA request type specifies the device endpoint that
        will be the source or destination of the DMA transfer.
        If "#dma-cells" is 2, the request type is a single cell, and the
        direction will be unidirectional (either RX or TX but not both).
        If "#dma-cells" is 3, the request type has two cells; the first
        one corresponds to the host to device direction (TX), the second one
        corresponds to the device to host direction (RX). The DMA channel is
        then bidirectional.

      - Channel: If set to 0xffffffff, any available channel will be allocated
        for the client. Otherwise, the exact channel specified will be used.
        The channel should be reserved on the DMA controller using the
        ingenic,reserved-channels property.

  ingenic,reserved-channels:
    $ref: /schemas/types.yaml#/definitions/uint32
    description: >
      Bitmask of channels to reserve for devices that need a specific
      channel. These channels will only be assigned when explicitly
      requested by a client. The primary use for this is channels 0 and
      1, which can be configured to have special behaviour for NAND/BCH
      when using programmable firmware.

required:
  - compatible
  - reg
  - interrupts
  - clocks

unevaluatedProperties: false

examples:
  - |
    #include <dt-bindings/clock/ingenic,jz4780-cgu.h>
    dma: dma-controller@13420000 {
      compatible = "ingenic,jz4780-dma";
      reg = <0x13420000 0x400>, <0x13421000 0x40>;

      interrupt-parent = <&intc>;
      interrupts = <10>;

      clocks = <&cgu JZ4780_CLK_PDMA>;

      #dma-cells = <2>;

      ingenic,reserved-channels = <0x3>;
    };