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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Fri, 16 Oct 2020 13:50:34 +0200
Message-ID: <CAMuHMdUof5Yb=5notGDYycJtZyLzGp2RPjJ=m6GVodBRDxw9ow@mail.gmail.com>
Subject: Re: [PATCH v3 2/7] dt-bindings: media: max9286: Document 'maxim,high-threshold'
To:     Jacopo Mondi <jacopo+renesas@jmondi.org>
Cc:     Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>,
        Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>,
        =?UTF-8?Q?Niklas_S=C3=B6derlund?= 
        <niklas.soderlund+renesas@ragnatech.se>,
        Linux Media Mailing List <linux-media@vger.kernel.org>,
        Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Hyun Kwon <hyunk@xilinx.com>,
        Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
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Hi Jacopo,

On Fri, Oct 16, 2020 at 12:09 PM Jacopo Mondi <jacopo+renesas@jmondi.org> wrote:
> Document the 'maxim,high-threshold' vendor property in the bindings
> document of the max9286 driver.
>
> The newly introduced boolean property allows controlling the initial
> configuration of the GMSL reverse control channel to accommodate
> remote serializers pre-programmed with the high threshold power
> supply noise immunity enabled.
>
> Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>

Thanks for your patch!

> --- a/Documentation/devicetree/bindings/media/i2c/maxim,max9286.yaml
> +++ b/Documentation/devicetree/bindings/media/i2c/maxim,max9286.yaml
> @@ -51,6 +51,19 @@ properties:
>    '#gpio-cells':
>      const: 2
>
> +  maxim,high-threshold:
> +    description: |
> +      A boolean property to increase the initial amplitude of the reverse
> +      control channel to compensate for remote serializers pre-programmed with
> +      high threshold noise-immunity.
> +
> +      Some camera modules (in example the RDACM20 one) include an on-board MCU
> +      that pre-programs the embedded serializer with reverse channel power
> +      supply noise immunity enabled. The deserializer shall increase its
> +      reverse channel amplitude to compensate that and be able to communicate
> +      with the remote end.
> +    type: boolean

Does this "high" threshold correspond to some numerical value?
I.e. could we run into a future need to support more values than just
true/false?
If yes, we may want to use a numerical value from the start.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds