Re: [PATCH 1/2] Documentation: dt-bindings: media: i2c: Add ROHM BU64754 bindings

From: Krzysztof Kozlowski
Date: Sun Sep 17 2023 - 13:32:39 EST


On 17/09/2023 12:33, Kieran Bingham wrote:
> Quoting Krzysztof Kozlowski (2023-09-17 10:37:07)
>> On 15/09/2023 18:59, Kieran Bingham wrote:
>>> Add YAML device tree bindings for the ROHM BU64754 VCM Motor Driver for
>>> Camera Autofocus.
>>>
>>> Signed-off-by: Kieran Bingham <kieran.bingham@xxxxxxxxxxxxxxxx>
>>> ---
>>
>> ...
>>
>>> +properties:
>>> + compatible:
>>> + items:
>>> + - enum:
>>> + - rohm,bu64754
>>> +
>>> + reg:
>>> + maxItems: 1
>>> +
>>> + vdd-supply:
>>
>> If the supply is not required, how the driver gets any power?
>
> It may not be controllable. It could be wired to be always on.

That's different. You talk now about board, I am talking about device.
Is the supply required for the device? If yes, then it should be
required by the bindings.

>
> The device has a low power mode which is controllable by software, so it
> could be always powered on and controlled via software only if desired.
> The driver handles that already as if the regulator isn't specified the
> power down register bits will be set to put it in low power mode.

Best regards,
Krzysztof