Re: [PATCH 1/2] dt-bindings: power: Add regulator-pd yaml file

From: Krzysztof Kozlowski
Date: Mon Aug 28 2023 - 14:43:08 EST


On 28/08/2023 20:39, Shenwei Wang wrote:
>
>
>> -----Original Message-----
>> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
>> Sent: Monday, August 28, 2023 12:11 PM
>> To: Shenwei Wang <shenwei.wang@xxxxxxx>; Ulf Hansson
>> <ulf.hansson@xxxxxxxxxx>
>> Cc: Rob Herring <robh+dt@xxxxxxxxxx>; Krzysztof Kozlowski
>> <krzysztof.kozlowski+dt@xxxxxxxxxx>; Conor Dooley <conor+dt@xxxxxxxxxx>;
>> Liam Girdwood <lgirdwood@xxxxxxxxx>; Mark Brown <broonie@xxxxxxxxxx>;
>> imx@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
>> dl-linux-imx <linux-imx@xxxxxxx>
>> Subject: [EXT] Re: [PATCH 1/2] dt-bindings: power: Add regulator-pd yaml file
>> On 28/08/2023 16:04, Shenwei Wang wrote:
>>
>>>>> Are you suggesting to move the regulator-pd to the imx directory and
>>>>> add a company prefix to the compatible string?
>>>>
>>>> There is no such part of iMX processor as such
>>>> regulator-power-domain, so I don't recommend that approach. DTS nodes
>>>> represent hardware, not your SW layers.
>>>>
>>>
>>> That's not always the case, as we do sometimes need a virtual device.
>>> As an example, the "regulator-fixed" acts as a software abstraction
>>> layer to create virtual regulator devices by interfacing with the underlying
>> GPIO drivers.
>>
>> Not true. This is a real regulator device. Real hardware on the board.
>> You can even see and touch it.
>>
>
> The physical hardware component is the GPIO pin, which is what you can only touch.

No. The regulator is the chip.

> The regulator functions virtually through software layer above of the GPIO driver. While
> we may call it a "regulator" or whatever else, this cannot obscure the fact that the underlying
> hardware is just a GPIO pin being used in a specialized way.

The regulator is some tiny little box, you can touch and called
ti,tps51632 or similar.



Best regards,
Krzysztof