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Date:   Thu, 13 Apr 2023 12:45:44 +0300
From:   Tony Lindgren <tony@atomide.com>
To:     Pavel Machek <pavel@ucw.cz>
Cc:     Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>,
        kernel list <linux-kernel@vger.kernel.org>,
        linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
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        mpartap@gmx.net, merlijn@wizzup.org, martin_rysavy@centrum.cz,
        phone-devel@vger.kernel.org, maemo-leste@lists.dyne.org
Subject: Re: Motorola Droid 4 -- Stopping charger when battery is full
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* Pavel Machek <pavel@ucw.cz> [230413 09:37]:
> 
> > * Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com> [230307 14:10]:
> > > Also, some guys have concerns about charging (and keeping it charged) @4.35,
> > > because of the possibly reduced battery life.
> > 
> > Yes for devices connected to a charger for long periods the battery will
> > bloat up within some weeks or months. This happens easily when using a
> > lapdock for example.
> > 
> > A simple and safe solution here might be that we allow charging up to
> > 4.35V only once when the charger is connected. Then we let the voltage
> > decrease to 4.2V (or whatever known good maintenance voltage) if the
> > charger stays connected.
> 
> Optimum solution would be user specifying "I want battery full
> tommorow at 8am" and doing the right thing.

I think you can already do that via sysfs with cron or at :)

> > For folks wanting to force the charge voltage higher we have the sysfs
> > interface.
> 
> Yep, we just need to make sure it is usable for this.

It should be but I have not tried for years. You need to first configure
the allowed voltage for battery via sysfs, then set the charge voltage
for the charger.

Regards,

Tony