Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Tue, 23 May 2023 18:29:15 +0100
From:   Conor Dooley <conor@kernel.org>
To:     Sean =?iso-8859-1?Q?Nyekj=E6r?= <sean@geanix.com>
Cc:     robh+dt@kernel.org, Lee Jones <lee@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        pascal Paillet <p.paillet@foss.st.com>,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 3/3] dt-bindings: mfd: stpmic1: add fsl,pmic-poweroff
 property
Message-ID: <20230523-flaccid-fossil-c9d09838dc64@spud>
References: <20230516132225.3012541-1-sean@geanix.com>
 <20230516132225.3012541-3-sean@geanix.com>
 <20230516-footprint-handoff-bcd553ff6146@spud>
 <9B1EE405-77D3-4980-9A13-9D4F87C1A64F@geanix.com>
MIME-Version: 1.0
Content-Type: multipart/signed; micalg=pgp-sha256;
        protocol="application/pgp-signature"; boundary="23BiRCaMKPuGXfik"
Content-Disposition: inline
In-Reply-To: <9B1EE405-77D3-4980-9A13-9D4F87C1A64F@geanix.com>
Precedence: bulk


--23BiRCaMKPuGXfik
Content-Type: text/plain; charset=iso-8859-1
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On Tue, May 23, 2023 at 11:55:50AM +0200, Sean Nyekj=E6r wrote:
> > On 16 May 2023, at 20.06, Conor Dooley <conor@kernel.org> wrote:
> > On Tue, May 16, 2023 at 03:22:24PM +0200, Sean Nyekjaer wrote:
> >> Document the new optional "fsl,pmic-poweroff" property.
> >>=20
> >> Signed-off-by: Sean Nyekjaer <sean@geanix.com>
> >> ---
> >> Documentation/devicetree/bindings/mfd/st,stpmic1.yaml | 8 ++++++++
> >> 1 file changed, 8 insertions(+)
> >>=20
> >> diff --git a/Documentation/devicetree/bindings/mfd/st,stpmic1.yaml b/D=
ocumentation/devicetree/bindings/mfd/st,stpmic1.yaml
> >> index 9573e4af949e..5183a7c660d2 100644
> >> --- a/Documentation/devicetree/bindings/mfd/st,stpmic1.yaml
> >> +++ b/Documentation/devicetree/bindings/mfd/st,stpmic1.yaml
> >> @@ -26,6 +26,14 @@ properties:
> >>=20
> >>   interrupt-controller: true
> >>=20
> >> +  st,pmic-poweroff:
> >> +    $ref: /schemas/types.yaml#/definitions/flag
> >> +    description: |
> >> +      if present, configure the PMIC to shutdown all power rails when
> >> +      power off sequence have finished.
> >> +      Use this option if the SoC should be powered off by external po=
wer management
> >> +      IC (PMIC).
> >=20
> > Just reading this description, this is sounding quite like a "software
> > behaviour" type of property, which are not permitted, rather than
> > describing some element of the hardware. Clearly you are trying to solve
> > an actual problem though, so try re-phrasing the description (and
> > property name) to focus on what exact hardware configuration it is that
> > you are trying to special-case.
> > Krzysztof suggested that the samsung,s2mps11-acokb-ground property in
> > samsung,s2mps11.yaml is addressing a similar problem, so that could be
> > good to look at.
>=20
> Better wording?
>       Indicates that the power management IC (PMIC) is used to power off =
the board.
>       So as the last step in the power off sequence set the SWOFF bit in =
the
>       main control register (MAIN_CR) register, to shutdown all power rai=
ls.

The description for the property that Krzysztof mentioned is
  samsung,s2mps11-acokb-ground:
    description: |
      Indicates that ACOKB pin of S2MPS11 PMIC is connected to the ground so
      the PMIC must manually set PWRHOLD bit in CTRL1 register to turn off =
the
      power. Usually the ACOKB is pulled up to VBATT so when PWRHOLD pin go=
es
      low, the rising ACOKB will trigger power off.

In other words, I am asking what (abnormal?) scenario there is that means
you need the property, rather than what setting the property does.
Or am I totally off, and this is the only way this PMIC works?

Cheers,
Conor.

--23BiRCaMKPuGXfik
Content-Type: application/pgp-signature; name="signature.asc"

-----BEGIN PGP SIGNATURE-----

iHUEABYIAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCZGz36wAKCRB4tDGHoIJi
0oHHAP9hYw2Fyk+QQUizn6YRH4cacENB1d9ChPXpsSyLDtFVvwD/aKAC10F+wFva
WT7XqtDEaJikR4HUtbr8QjftlyFbtwE=
=Fjiv
-----END PGP SIGNATURE-----

--23BiRCaMKPuGXfik--