Re: [PATCH v3 2/9] dt-bindings: dma: nvidia,tegra186-gpc-dma: Make reset optional

[Jon Hunter <jonathanh@nvidia.com>]

On 16/03/2026 17:18, Akhil R wrote:
> On Tegra264, GPCDMA reset control is not exposed to Linux and is handled
> by the boot firmware.
> 
> Although the reset was not exposed in Tegra234 as well, the firmware
> supported a dummy reset which just returns success on reset without doing
> an actual reset. This is also not supported in Tegra264. Therefore mark
> 'reset' and 'reset-names' properties as required only for devices prior
> to Tegra264.
> 
> This also necessitates that the Tegra264 compatible be standalone and
> cannot have the fallback compatible of Tegra186. Since there is no
> functional impact, we keep reset as required for Tegra234 to avoid
> breaking the ABI.
> 

This is a fix for Tegra264 and so having a fixes tag here seems appropriate.

> Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
> ---
>   .../bindings/dma/nvidia,tegra186-gpc-dma.yaml | 25 +++++++++++++------
>   1 file changed, 18 insertions(+), 7 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml b/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml
> index b5d8fd0b281d..b849d4cc2901 100644
> --- a/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml
> +++ b/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml
> @@ -16,16 +16,14 @@ maintainers:
>     - Rajesh Gumasta <rgumasta@nvidia.com>
>     - Akhil R <akhilrajeev@nvidia.com>
>   
> -allOf:
> -  - $ref: dma-controller.yaml#
> -
>   properties:
>     compatible:
>       oneOf:
> -      - const: nvidia,tegra186-gpcdma
> +      - enum:
> +          - nvidia,tegra264-gpcdma
> +          - nvidia,tegra186-gpcdma
>         - items:
>             - enum:
> -              - nvidia,tegra264-gpcdma
>                 - nvidia,tegra234-gpcdma
>                 - nvidia,tegra194-gpcdma
>             - const: nvidia,tegra186-gpcdma
> @@ -69,12 +67,25 @@ required:
>     - compatible
>     - reg
>     - interrupts
> -  - resets
> -  - reset-names
>     - "#dma-cells"
>     - iommus
>     - dma-channel-mask
>   
> +allOf:
> +  - $ref: dma-controller.yaml#
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            enum:
> +              - nvidia,tegra186-gpcdma
> +              - nvidia,tegra194-gpcdma
> +              - nvidia,tegra234-gpcdma
> +    then:
> +      required:
> +        - resets
> +        - reset-names
> +
>   additionalProperties: false
>   
>   examples:

-- 
nvpublic