From: Paul Cercueil Date: Mon, 6 Dec 2021 17:42:55 +0000 (+0000) Subject: dt-bindings: dma: ingenic: Support #dma-cells = <3> X-Git-Tag: v5.17-rc1~45^2~39 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=dafa79a10ed70683811295cb68deca2d30c22ef4;p=linux-block.git dt-bindings: dma: ingenic: Support #dma-cells = <3> Extend the binding to support specifying a different request type for each direction. Signed-off-by: Paul Cercueil Link: https://lore.kernel.org/r/20211206174259.68133-3-paul@crapouillou.net Signed-off-by: Vinod Koul --- diff --git a/Documentation/devicetree/bindings/dma/ingenic,dma.yaml b/Documentation/devicetree/bindings/dma/ingenic,dma.yaml index 2607b403277e..3b0b3b919af8 100644 --- a/Documentation/devicetree/bindings/dma/ingenic,dma.yaml +++ b/Documentation/devicetree/bindings/dma/ingenic,dma.yaml @@ -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.