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 Diff line number Diff line
@@ -44,13 +44,19 @@ properties: 
    maxItems: 1



  "#dma-cells":

    const: 2

    enum: [2, 3]

    description: >

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

      to the DMA controller plus the following 2 integer cells:



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

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

      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.