linux-kernel - Re: [PATCH] regulator: lp873x: Update the enable mask for LDOs and BUCKs

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Message-ID: <20171009155026.63aghfli7bkemiux@sirena.co.uk>
Date:   Mon, 9 Oct 2017 16:50:26 +0100
From:   Mark Brown <broonie@...nel.org>
To:     Tero Kristo <t-kristo@...com>
Cc:     Keerthy <j-keerthy@...com>, linux-kernel@...r.kernel.org,
        lee.jones@...aro.org, linux-omap@...r.kernel.org
Subject: Re: [PATCH] regulator: lp873x: Update the enable mask for LDOs and
 BUCKs

On Mon, Oct 09, 2017 at 06:35:14PM +0300, Tero Kristo wrote:

> The EN signal coming in to the PMIC is actually used to poweroff the system
> completely. There is no other mechanism for doing this in lp873x based
> systems, they removed the bit for controlling dev-power-off from the
> register space. If the EN bit is down for a specific regulator, it won't go
> down when attempting to poweroff the system, otherwise the state of a
> regulator is the result of (EN_PIN | EN_BIT).

This should be clear from the changelog (and probably the code as well).

> I wonder if we should tie this somehow to the system-power-controller
> property though.... If the PMIC is not system-power-controller, we should
> disable the EN_PIN_CTRL from all regulators so that they don't go down if
> the EN_PIN itself is floating for example.

Seems plausible, if someone does decided to use control at runtime the
behaviour can always be changed if the GPIO is present.

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