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

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Date:   Tue, 10 Oct 2017 07:34:52 +0530
From:   Keerthy <j-keerthy@...com>
To:     Mark Brown <broonie@...nel.org>, Tero Kristo <t-kristo@...com>
CC:     <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 Monday 09 October 2017 09:20 PM, Mark Brown wrote:
> 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.

Okay. So Implement a poweroff function where EN pin magic is done based
on system-power-controller property?

>