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Date:   Wed, 17 Mar 2021 14:02:42 +0000
Message-ID: <87czvxj2t9.wl-maz@kernel.org>
From:   Marc Zyngier <maz@kernel.org>
To:     Maulik Shah <mkshah@codeaurora.org>
Cc:     swboyd@chromium.org, bjorn.andersson@linaro.org,
        linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org,
        robh+dt@kernel.org, dianders@chromium.org, rnayak@codeaurora.org,
        lsrao@codeaurora.org, devicetree@vger.kernel.org
Subject: Re: [PATCH 1/3] arm64: dts: qcom: sm8350: Remove second reg from pdc
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        <bce03166-e65b-198c-8b93-39e0c218aaed@codeaurora.org>
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On Wed, 17 Mar 2021 09:48:09 +0000,
Maulik Shah <mkshah@codeaurora.org> wrote:
> 
> Hi Marc,
> 
> On 3/17/2021 2:47 PM, Marc Zyngier wrote:
> > On Wed, 17 Mar 2021 05:29:54 +0000,
> > Maulik Shah <mkshah@codeaurora.org> wrote:
> >> PDC interrupt controller driver do not use second reg. Remove it.
> > This is a DT file, not a driver. What the driver does is irrelevant.
> > 
> > The real question is: what does this range do?
> > 
> > Thanks,
> > 
> > 	M.
> 
> This is to set interrupt type in SPI config for which there was a
> change [1] but has not gone in for upstream PDC driver.
> 
> The second reg is not used in upstream PDC driver, probably when
> posting downstream DT changes for sm8350/sm8250 it was carried in
> device node as is.
> 
> As its not mentioned in bindigs as well, dtbs_check reports it as
> additional reg when converted to yaml.

Then I'd rather you provide accurate documentation in the binding
rather than changing the DT files. Other operating systems may use it,
and it isn't unlikely that Linux could use the feature at some point.

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.