From 54e09c8e2d3b0b7d603a64368fa49fe2a8031dd1 Mon Sep 17 00:00:00 2001 From: Ken Sloat Date: Fri, 6 Dec 2024 06:50:18 -0500 Subject: [PATCH] dt-bindings: dma: st-stm32-dmamux: Add description for dma-cell values The dma-cell values for the stm32-dmamux are used to craft the DMA spec for the actual controller. These values are currently undocumented leaving the user to reverse engineer the driver in order to determine their meaning. Add a basic description, while avoiding duplicating information by pointing the user to the associated DMA docs that describe the fields in depth. Signed-off-by: Ken Sloat Acked-by: Conor Dooley Reviewed-by: Amelie Delaunay Link: https://lore.kernel.org/r/20241206115018.1155149-1-ksloat@cornersoftsolutions.com Signed-off-by: Vinod Koul --- .../devicetree/bindings/dma/stm32/st,stm32-dmamux.yaml | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/Documentation/devicetree/bindings/dma/stm32/st,stm32-dmamux.yaml b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dmamux.yaml index f26c914a3a9a5..b7bca1a837692 100644 --- a/Documentation/devicetree/bindings/dma/stm32/st,stm32-dmamux.yaml +++ b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dmamux.yaml @@ -15,6 +15,16 @@ allOf: properties: "#dma-cells": const: 3 + description: | + Each cell represents the following: + 1. The mux input number/line for the request + 2. Bitfield representing DMA channel configuration that is passed + to the real DMA controller + 3. Bitfield representing device dependent DMA features passed to + the real DMA controller + + For bitfield definitions of cells 2 and 3, see the associated + bindings doc for the actual DMA controller in st,stm32-dma.yaml. compatible: const: st,stm32h7-dmamux -- 2.47.2