Re: [PATCH 2/3] ASoC: dt-bindings: sama7g5-pdmc: add microchip,startup-delay-us binding

From: Krzysztof Kozlowski
Date: Thu Feb 16 2023 - 05:04:46 EST


On 14/02/2023 17:14, Claudiu Beznea wrote:
> Add microchip,startup-delay-us binding to let PDMC users to specify
> startup delay.
>
> Signed-off-by: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
> ---
> .../devicetree/bindings/sound/microchip,sama7g5-pdmc.yaml | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/sound/microchip,sama7g5-pdmc.yaml b/Documentation/devicetree/bindings/sound/microchip,sama7g5-pdmc.yaml
> index c4cf1e5ab84b..9b40268537cb 100644
> --- a/Documentation/devicetree/bindings/sound/microchip,sama7g5-pdmc.yaml
> +++ b/Documentation/devicetree/bindings/sound/microchip,sama7g5-pdmc.yaml
> @@ -67,6 +67,12 @@ properties:
> maxItems: 4
> uniqueItems: true
>
> + microchip,startup-delay-us:
> + description: |
> + Specifies the delay in microseconds that needs to be applied after
> + enabling the PDMC microphones to avoid unwanted noise due to microphones
> + not being ready.

Is this some hardware delay? Or OS? If OS, why Linux specific delay is
put into DT?

Best regards,
Krzysztof