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Date:   Mon, 24 Feb 2020 12:31:22 +0000
From:   Mark Brown <broonie@kernel.org>
To:     "H. Nikolaus Schaller" <hns@goldelico.com>
Cc:     Andreas Kemnade <andreas@kemnade.info>, j.neuschaefer@gmx.net,
        contact@paulk.fr, GNUtoo@cyberdimension.org, josua.mayer@jm0.eu,
        lgirdwood@gmail.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH RFC] regulator: core: fix handling negative voltages e.g.
 in EPD PMICs
Message-ID: <20200224123122.GH6215@sirena.org.uk>
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On Mon, Feb 24, 2020 at 01:22:21PM +0100, H. Nikolaus Schaller wrote:
> > Am 24.02.2020 um 13:05 schrieb Mark Brown <broonie@kernel.org>:

> > This is what'd be needed, your approach here is a bit of a hack and
> > leaves some values unrepresentable if they overlap with errnos which
> > obviously has issues if someone has a need for those values.

> Negative ERRNOs have BIT(31) set.

This code is working with the numberic representation, not with the
bitwise representation - it's using -MAX_ERRNO. =20

> But then it seems to be a little inconsistent that the voltage
> parameters of regulator_set_voltage_unlocked() are signed integers
> and not unsigned.

> So shouldn't that be protected against attempting to set negative voltage=
s?

Or just convert it to unsigned, I don't recall there being any
particular reason why it's signed.

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