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Date:   Fri, 27 Jan 2023 22:33:14 +0100
From:   Francesco Dolcini <francesco@dolcini.it>
To:     linux-kernel@vger.kernel.org, Liam Girdwood <lgirdwood@gmail.com>,
        Mark Brown <broonie@kernel.org>
Subject: fixed-regulator with enable from another regulator
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Hello all,
I am trying to figure out if it is possible with the current
regulator-fixed or with any other solution already implemented in Linux
to have a regulator enabled from another one.

I am not talking about the regulator vin-supply, I am really talking
about the enable input signal of a LDO connected to the output of another
regulator, a sort of "chained" regulator.

As an example something like this

<reg_1v8>[out] ---> [vin-supply]<reg_1v0>[out] --->
<reg_3v3>[out] ---> [enable]

<reg_1v8>[out] ---> [vin-supply]<reg_1v2>[out] --->
<reg_3v3>[out] ---> [enable]

<gpio1> ---> [enable]<reg_3v3>[out]--->

in which toggling <gpio1> control 3 different outputs.

I am still not 100% sure if describing this specific hardware connection
would be required on my system, maybe I can just ignore all of that.

Any thought?

Francesco