[PATCH v1] dt-bindings: dma: st-stm32-dmamux: Add description for dma-cell values

[Krzysztof Kozlowski]

On 05/12/2024 16:32, Ken Sloat wrote:
> 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 <ksloat at cornersoftsolutions.com>
> ---
> .../bindings/dma/stm32/st,stm32-dmamux.yaml | 11 +++++++++++
> 1 file changed, 11 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/dma/stm32/st,stm32-dmamux.yaml
> b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dmamux.yaml
> index f26c914a3a9a..aa2e52027ee6 100644
> --- a/Documentation/devicetree/bindings/dma/stm32/st,stm32-dmamux.yaml
> +++ b/Documentation/devicetree/bindings/dma/stm32/st,stm32-dmamux.yaml
> @@ -15,6 +15,17 @@ allOf:
> properties:
> "#dma-cells":
> const: 3

Your patch is corrupted. Please use git send-email or b4 or b4+relay.

> + description: |
> + Should be set to <3> with each cell representing the following:

Drop this part, const says this.

> + 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 the mux is connected

This does not sound right. This is the binding for DMA controller, so
you are saying "please look at itself". I suggest to drop this as well.


Best regards,
Krzysztof