Commit dafa79a1 authored by Paul Cercueil's avatar Paul Cercueil Committed by Vinod Koul
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dt-bindings: dma: ingenic: Support #dma-cells = <3> 



Extend the binding to support specifying a different request type for
each direction.

Signed-off-by: default avatarPaul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/20211206174259.68133-3-paul@crapouillou.net


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent e0699a75

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

+11 −5
Original line number Original line Diff line number Diff line
@@ -44,13 +44,19 @@ properties: 
    maxItems: 1

    maxItems: 1





  "#dma-cells":

  "#dma-cells":

    const: 2

    enum: [2, 3]

    description: >

    description: >

      DMA clients must use the format described in dma.txt, giving a phandle

      DMA clients must use the format described in dma.txt, giving a phandle

      to the DMA controller plus the following 2 integer cells:

      to the DMA controller plus the following integer cells:





      - Request type: The DMA request type for transfers to/from the

      - Request type: The DMA request type specifies the device endpoint that

        device on the allocated channel, as defined in the SoC documentation.

        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

      - Channel: If set to 0xffffffff, any available channel will be allocated

        for the client. Otherwise, the exact channel specified will be used.

        for the client. Otherwise, the exact channel specified will be used.