Documentation/devicetree/bindings/dma/dma-common.yaml

   1 # SPDX-License-Identifier: GPL-2.0
   2 %YAML 1.2
   3 ---
   4 $id: http://devicetree.org/schemas/dma/dma-common.yaml#
   5 $schema: http://devicetree.org/meta-schemas/core.yaml#
   6
   7 title: DMA Engine Generic Binding
   8
   9 maintainers:
  10   - Vinod Koul <vkoul@kernel.org>
  11
  12 description:
  13   Generic binding to provide a way for a driver using DMA Engine to
  14   retrieve the DMA request or channel information that goes from a
  15   hardware device to a DMA controller.
  16
  17 select: false
  18
  19 properties:
  20   "#dma-cells":
  21     minimum: 1
  22     # Should be enough
  23     maximum: 255
  24     description:
  25       Used to provide DMA controller specific information.
  26
  27   dma-channel-mask:
  28     description:
  29       Bitmask of available DMA channels in ascending order that are
  30       not reserved by firmware and are available to the
  31       kernel. i.e. first channel corresponds to LSB.
  32       The first item in the array is for channels 0-31, the second is for
  33       channels 32-63, etc.
  34     allOf:
  35       - $ref: /schemas/types.yaml#/definitions/uint32-array
  36     items:
  37       minItems: 1
  38       # Should be enough
  39       maxItems: 255
  40
  41   dma-channels:
  42     $ref: /schemas/types.yaml#definitions/uint32
  43     description:
  44       Number of DMA channels supported by the controller.
  45
  46   dma-requests:
  47     $ref: /schemas/types.yaml#definitions/uint32
  48     description:
  49       Number of DMA request signals supported by the controller.
  50
  51 required:
  52   - "#dma-cells"