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References: <20230517144144.365631-1-romain.perier@gmail.com>
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From:   Daniel Palmer <daniel@0x0f.com>
Date:   Tue, 30 May 2023 08:06:13 +0900
Message-ID: <CAFr9PX=NmgX5Ww55bz+oM15fhqofFQH=PGs_T6Gkfs4g8ZrFXw@mail.gmail.com>
Subject: Re: [PATCH 1/3] rtc: Add support for the SSD20xD RTC
To:     Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc:     Romain Perier <romain.perier@gmail.com>,
        Alessandro Zummo <a.zummo@towertech.it>,
        Rob Herring <robh+dt@kernel.org>, linux-rtc@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org
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Hi Alexandre,

On Tue, 30 May 2023 at 07:40, Alexandre Belloni
<alexandre.belloni@bootlin.com> wrote:
>
> Hello,
>
> On 17/05/2023 16:41:42+0200, Romain Perier wrote:
> > Newer SigmaStar SSD20xD SoCs contain a really low power RTC (300uA claimed),
>
> The low power RTCs are more on the side of a few tenth of nA. RV3028
> consumes 40nA, including the crystal. AB1805 consumes 14nA with an RC
> oscillator. It is funny how SoC vendors think they are low power ;)

To be fair to them I think the 300uA claim is for the whole SoC in
RTC-only deep sleep.
Whatever logic is powered on alongside the RTC to trigger wake up will
be part of that number I guess.

Cheers,

Daniel