Re: [PATCH] dt-bindings: soc: imx8mp-media-blk-ctrl: Add LDB into DT example

[Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>]

On 08/07/2022 17:32, Marek Vasut wrote:
> On 7/4/22 10:00, Krzysztof Kozlowski wrote:
>> On 01/07/2022 10:06, Marek Vasut wrote:
>>> In the local patch I have to imx8mp.dtsi , the simple-mfd had to be
>>> added for the ldb bridge child node to bind.
>>>
>>>> 'simple-mfd' is saying the child has 0 dependence on the parent. IMO,
>>>> 'syscon' contradicts that, but that's an all to common pattern. You are
>>>> saying all the clocks (or any other resources) in the parent can be off
>>>> and the LDB bridge is still functional.
>>>
>>> The bridge itself should work even if the block control is clocked off.
>>> The block controller apb (register) clock have to be enabled only when
>>> accessing these two LDB registers, which should be handled by runtime
>>> PM. Or what am I missing here ?
>>
>> If I understand correctly, you need the device's APB clocks to be
>> enabled to use the child device? You have a dependency between child and
>> parent, so it is not a simple-mfd.
> 
> OK, then ... what is it ? Some sort of hint would be helpful.

I don't have the hardware manual to know what is it exactly. Some device
which has its own bindings and fsl,imx8mp-media-blk-ctrl compatible.

You already received hint what should you do with that device....
"What I meant, is that probably you should populate children from the
driver instead of adding simple-mfd compatible."


Best regards,
Krzysztof

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