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From:   Alexandru M Stan <amstan@chromium.org>
Date:   Thu, 15 Oct 2020 14:29:05 -0700
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Subject: Re: [PATCH v2 2/3] ARM: dts: rockchip: veyron: Remove 0 point from brightness-levels
To:     Daniel Thompson <daniel.thompson@linaro.org>
Cc:     Thierry Reding <thierry.reding@gmail.com>,
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        <u.kleine-koenig@pengutronix.de>, Lee Jones <lee.jones@linaro.org>,
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        Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
        Heiko Stuebner <heiko@sntech.de>,
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        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Douglas Anderson <dianders@chromium.org>,
        Enric Balletbo i Serra <enric.balletbo@collabora.com>,
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On Wed, Oct 14, 2020 at 7:19 AM Daniel Thompson
<daniel.thompson@linaro.org> wrote:
>
> On Tue, Oct 13, 2020 at 01:01:02AM -0700, Alexandru Stan wrote:
> > After the "PWM backlight interpolation adjustments" patches, the
> > backlight interpolation works a little differently. The way these
> > dts files were working before was relying on a bug (IMHO).
> >
> > Remove the 0-3 range since otherwise we would have a 252 long
> > interpolation that would slowly go between 0 and 3, looking really bad
> > in userspace.
> >
> > We don't need the 0% point, userspace seems to handle this just fine
> > because it uses the bl_power property to turn off the display.
> >
> > Signed-off-by: Alexandru Stan <amstan@chromium.org>
>
> Acked-by: Daniel Thompson <daniel.thompson@linaro.org>

Thank you!

>
> Note also shouldn't this be patch 1 of the set. AFAICT it makes sense
> whether or not the interpolation algorithm is changed.

Yeah, I guess it could be. Sorry I didn't think of it that way before,
I'm used to landing things in a group.

In particular on veyron I assume it will almost be a noop without
having my driver patch (especially with the findings of 0% not being
that important).

Feel free to land this independently.

>
>
> Daniel.

Alexandru Stan (amstan)