Re: [PATCH v2 5/8] dt-bindings: display: allwinner: Add DE33 planes

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] The binding specifies an independent memory-mapped region (`reg`) but completely omits required hardware dependencies like `clocks` and `resets`.
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commit c4cb2c3df2e7559ecf6e92deffc259a4516494c5
Author: Jernej Skrabec <jernej.skrabec@gmail.com>

dt-bindings: display: allwinner: Add DE33 planes

This commit adds a new device tree binding for the Allwinner Display Engine
3.3 planes. These planes act as shared resources between mixers and are
assigned using registers within the display clocks MMIO space.

> diff --git a/Documentation/devicetree/bindings/display/allwinner,sun50i-h616-de33-planes.yaml b/Documentation/devicetree/bindings/display/allwinner,sun50i-h616-de33-planes.yaml
> new file mode 100644
> index 0000000000000..0a07cb8a5f798
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/allwinner,sun50i-h616-de33-planes.yaml
[ ... ]
> +properties:
> +  compatible:
> +    enum:
> +      - allwinner,sun50i-h616-de33-planes
> +
> +  reg:
> +    maxItems: 1
> +
> +  allwinner,plane-mapping:
> +    $ref: /schemas/types.yaml#/definitions/phandle
> +    description:
> +      Phandle of the device responsible for assigning (mapping) planes
> +      between mixers.
> +
> +required:
> +  - compatible
> +  - reg
> +  - allwinner,plane-mapping

Does this binding also need to specify clocks and resets as required
properties?

Since this node represents an independent MMIO hardware block, omitting its
hardware dependencies relies on the sibling mixer driver to implicitly power
the bus.

If the sun8i-mixer driver is unbound or fails to probe, the shared display
bus clock is left disabled. Would a subsequent read of the planes regmap
exposed to userspace via debugfs perform an MMIO read on an unclocked bus
and result in a fatal external abort (SError)?

Should clocks and resets be added to the binding so the planes driver can
manage its own bus access safely (for example, by using
regmap_mmio_attach_clk())?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260509190015.79086-1-jernej.skrabec@siol.net?part=5