linux-kernel - RE: [PATCH] regulator: da9063: disable unused voltage monitors

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Date:   Thu, 14 Jul 2022 09:36:01 +0000
From:   DLG Adam Thomson <DLG-Adam.Thomson.Opensource@...renesas.com>
To:     Benjamin Bara <bbara93@...il.com>,
        "support.opensource@...semi.com" <support.opensource@...semi.com>,
        "lgirdwood@...il.com" <lgirdwood@...il.com>,
        "broonie@...nel.org" <broonie@...nel.org>,
        "lee.jones@...aro.org" <lee.jones@...aro.org>
CC:     "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        Benjamin Bara <benjamin.bara@...data.com>,
        Richard Leitner <richard.leitner@...data.com>
Subject: RE: [PATCH] regulator: da9063: disable unused voltage monitors

On 13 July 2022 13:50, Benjamin Bara wrote:

> From: Benjamin Bara <benjamin.bara@...data.com>
> 
> This enables the kernel to disable the voltage monitor of unused regs.
> 
> Some boards might use the PWR_OK functionality, which asserts GP_FB2
> if each measured voltage is in-range.
> However, if a regulator (which is enabled and monitored) is disabled,
> also its voltage monitor must be disabled to keep a valid PWR_OK state.

This proposal seemingly doesn't work. If you disable monitoring of a regulator,
and no other regulators are being monitored at that point, then GP_FB2 will no
longer be asserted and you have the same issue. What's more this patch impacts
all users and there's no means to re-enable monitoring. Certainly in the current
state this isn't a valid change.

What exactly is the problem you're attempting to resolve through this patch?