linux-kernel - Re: [PATCH 2/3] regulator: max77693: Also manipulate the fast charge current

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Message-ID: <20160927161502.ygfa26xk7sdj2uot@sirena.org.uk>
Date:   Tue, 27 Sep 2016 09:15:02 -0700
From:   Mark Brown <broonie@...nel.org>
To:     Wolfgang Wiedmeyer <wolfgit@...dmeyer.de>
Cc:     Krzysztof Kozlowski <krzk@...nel.org>, sre@...nel.org,
        dbaryshkov@...il.com, dwmw2@...radead.org, cw00.choi@...sung.com,
        b.zolnierkie@...sung.com, lgirdwood@...il.com,
        lee.jones@...aro.org, linux-pm@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/3] regulator: max77693: Also manipulate the fast charge
 current

On Tue, Sep 27, 2016 at 03:50:42PM +0200, Wolfgang Wiedmeyer wrote:

> When charging is disabled (e.g. by removing the USB cable) the charge
> current is not reset to zero. So if I expose the current by the
> CURRENT_NOW property, it incorrectly reports the current that was set
> when charging was enabled, although there is no charging going on
> anymore. So I felt the need to update the charge current every time the
> charger gets enabled or disabled.
> Initially, the charge current is set to zero, so I think it needs to be
> set at least at the beginning to enable charging.

Are you sure that the register value you're looking at is the actual
charge current right now and not just the maximum that the charger will
try to use depending on the conditions (supply available, battery
state...)?  It seems like you're acting as though it's the latter but
that's not what the chip is doing.

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