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Date:   Wed, 24 Feb 2021 08:54:32 -0800
From:   Matthias Kaehlcke <mka@chromium.org>
To:     Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Cc:     Andy Gross <agross@kernel.org>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Rob Herring <robh+dt@kernel.org>,
        "open list:DRM DRIVER FOR MSM ADRENO GPU" 
        <linux-arm-msm@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>,
        Douglas Anderson <dianders@chromium.org>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>
Subject: Re: [PATCH 3/3] arm64: dts: qcom: sc7180: Delete charger thermal
 zone and ADC channel for lazor <= rev3
Message-ID: <YDaEyASeJdgs3hS9@google.com>
References: <20210219181032.1.I23e12818c4a841ba9c37c60b3ba8cfeeb048285f@changeid>
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 <CAA8EJpoCBe_5khmWPGvr35zBWdcoSJ4OeY=6Nw1diTsNtv7EpA@mail.gmail.com>
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On Tue, Feb 23, 2021 at 02:12:30PM +0300, Dmitry Baryshkov wrote:
> Hi,
> 
> On Sat, 20 Feb 2021 at 05:13, Matthias Kaehlcke <mka@chromium.org> wrote:
> >
> > Lazor rev3 and older are stuffed with a 47k NTC as thermistor for
> > the charger temperature which currently isn't supported by the
> > PM6150 ADC driver. Delete the charger thermal zone and ADC channel
> > to avoid the use of bogus temperature values.
> 
> Should we just expand the adc/adc-tm drivers with additional calibration tables?

Generally that seems desirable, I'm not sure about the process, I guess
someone with access to a climate chamber would have to create these tables?

I think it would also require an extension of the DT bindings, currently
the ADC driver assumes that a 100k NTC is connected, something in the DT
would have to indicate the thermistor type.

We want to remove the bogus temperatures from the system now, if support for
47k NTCs is added at some point we can consider changing the DT again.