[PATCH v4 1/4] dt-bindings: dmaengine: Add dmamux for CV18XX/SG200X series SoC

Krzysztof Kozlowski krzysztof.kozlowski at linaro.org
Mon Mar 18 01:31:51 PDT 2024


On 18/03/2024 09:30, Inochi Amaoto wrote:
>>> @@ -0,0 +1,47 @@
>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>>> +%YAML 1.2
>>> +---
>>> +$id: http://devicetree.org/schemas/dma/sophgo,cv1800-dmamux.yaml#
>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>> +
>>> +title: Sophgo CV1800/SG200 Series DMA mux
>>> +
>>> +maintainers:
>>> +  - Inochi Amaoto <inochiama at outlook.com>
>>> +
>>> +allOf:
>>> +  - $ref: dma-router.yaml#
>>> +
>>> +properties:
>>> +  compatible:
>>> +    const: sophgo,cv1800-dmamux
>>> +
>>> +  reg:
>>> +    maxItems: 2
>>
>> You need to describe the items.
>>
> 
> I wonder whether reg-name should be introduced, or item description is
> just enough?

items:
 - description:
 - description:

is enough

> 
>>> +
>>> +  '#dma-cells':
>>> +    const: 3
>>> +    description:
>>> +      The first cells is DMA channel. The second one is device id.
>>> +      The third one is the cpu id.
>>> +
>>> +  dma-masters:
>>> +    maxItems: 1
>>> +
>>> +  dma-requests:
>>> +    const: 8
>>> +
>>> +required:
>>> +  - '#dma-cells'
>>
>> reg is not required? How do you perform any IO?
> 
> This device is part of the syscon. The IO is performed by the offset.
> In the v2, Rob suggest me add the "reg" property to describe registers.
> He also mentioned that driver may not use this info, so I do not make
> this a must.

OK

Best regards,
Krzysztof




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