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Message-ID: <4ebbbd58-e9d2-6d7d-63d3-d128840238cb@rocketmail.com>
Date:   Mon, 27 Mar 2023 22:22:04 +0200
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Subject: Re: [PATCH 00/10] Add RT5033 charger device driver
To:     Pavel Machek <pavel@ucw.cz>
Cc:     Sebastian Reichel <sre@kernel.org>, Lee Jones <lee@kernel.org>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Mark Brown <broonie@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Beomho Seo <beomho.seo@samsung.com>,
        Chanwoo Choi <cw00.choi@samsung.com>,
        Stephan Gerhold <stephan@gerhold.net>,
        Raymond Hackley <raymondhackley@protonmail.com>,
        linux-pm@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, ~postmarketos/upstreaming@lists.sr.ht
References: <cover.1677620677.git.jahau.ref@rocketmail.com>
 <cover.1677620677.git.jahau@rocketmail.com> <20230325160819.GA1820@bug>
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From:   Jakob Hauser <jahau@rocketmail.com>
In-Reply-To: <20230325160819.GA1820@bug>
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Hi Pavel,

On 25.03.23 17:08, Pavel Machek wrote:
> Hi!

...

>> - The third option of the rt5033 chip is enabling charging termination. This
>>    also enables a re-charge cycle. When the charging current sinks below the
>>    end-of-charge current, the chip stops charging. The sysfs state changes to
>>    "not charging". When the voltage gets 0.1 V below the end-of-charge constant
>>    voltage, re-charging starts. Then again, when charging current sinks below
>>    the end-of-charge current, the chip stops charging. And so on, going up and
>>    down in re-charge cycles. In case the power consumption is high (e.g. tuning
>>    on the display of the mobile device), the current goes into an equilibrium.
>>    The downside of this charging termination option: When reaching the end-of-
>>    charge current, the capacity might not have reached 100 % yet. The capacity
>>    to reach probably depends on power consumption and battery wear. On my mobile
>>    device, capacity reaches 98 %, drops to 96 % until re-charging kicks in,
>>    climbs to 98 %, drops to 96 %, and so on. Not reaching 100 % is a bit
>>    confusing to the user, too.
> 
> Is the system powered from the battery in the not-charging case?

Yes, at RT5033 in the "not charging" state the system draws the power 
from the battery.

...

Kind regards,
Jakob