Re: [PATCH] dt-bindings: dma: ti,dma-crossbar: Convert to DT schema

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider:
- [Low] The YAML conversion drops critical documentation detailing the DMA specifier layout for clients (formatting and meaning of the `#dma-cells` parameters).
- [Low] The `ti,reserved-dma-request-ranges` property is defined as a `uint32-matrix` but lacks constraints on its inner tuple dimensions.
--

--- Patch [1]: [PATCH] dt-bindings: dma: ti,dma-crossbar: Convert to DT schema ---
commit adc2900e39482ff7d8433cdf6ef2cabd79619bea
Author: Bhargav Joshi <j.bhargav.u@gmail.com>

dt-bindings: dma: ti,dma-crossbar: Convert to DT schema

Convert Texas Instruments DMA Crossbar from text to DT schema

> diff --git a/Documentation/devicetree/bindings/dma/ti,dra7-dma-crossbar.yaml b/Documentation/devicetree/bindings/dma/ti,dra7-dma-crossbar.yaml
> new file mode 100644
> index 0000000000000..287260396098f
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/dma/ti,dra7-dma-crossbar.yaml
> @@ -0,0 +1,105 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/dma/ti,dra7-dma-crossbar.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Texas Instruments DMA Crossbar (DMA request router)
> +
> +maintainers:
> +  - Bhargav Joshi <j.bhargav.u@gmail.com>
> +  - Peter Ujfalusi <peter.ujfalusi@gmail.com>
> +
> +properties:
> +  compatible:
> +    enum:
> +      - ti,dra7-dma-crossbar
> +      - ti,am335x-edma-crossbar
> +
> +  reg:
> +    maxItems: 1
> +
> +  "#dma-cells":
> +    minimum: 1
> +    maximum: 3
> +

[Severity: Low]
Does this conversion unintentionally drop the documentation explaining the DMA
specifier layout for clients?

The deleted text binding included details about the formatting and meaning of
the parameters, which device tree authors need to correctly formulate the dmas
property:

For ti,am335x-edma-crossbar: the meaning of parameters of dmas for clients:
dmas = <&edma_xbar 12 0 1>; where <12> is the DMA request number, <0> is the
TC the event should be assigned and <1> is the mux selection for in the
crossbar.

Could this description be preserved in the YAML schema, either in the 
top-level description or under this #dma-cells property?

> +  dma-requests:
> +    minimum: 1
> +    maximum: 256
> +
> +  dma-masters:
> +    maxItems: 1
> +
> +  ti,dma-safe-map:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description: Safe routing value for unused request lines
> +
> +  ti,reserved-dma-request-ranges:
> +    $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +    description:
> +      DMA request ranges which should not be used when mapping xbar input to
> +      DMA request, they are either allocated to be used by for example the DSP
> +      or they are used as memcpy channels in eDMA.

[Severity: Low]
Should this uint32-matrix property include constraints on its inner tuple 
dimensions?

Without items definitions to enforce a tuple length of 2 (start and length), 
schema validation might fail to reject device trees that have incorrect 
tuple sizes like <10 5 99>.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260708-ti-dma-crossbar-v1-1-f62796428f13@gmail.com?part=1