Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20211025144718.157794-1-marcan@marcan.st> <20211025144718.157794-3-marcan@marcan.st>
 <YXhINE00HG6hbQI4@robh.at.kernel.org> <c0f2587c-ab69-8194-e618-ce7919c1aeb1@marcan.st>
 <CAL_JsqJbVcqy8n0EroV=nFZoJ_WAr+JbrDf-c1jso856NghC2A@mail.gmail.com>
In-Reply-To: <CAL_JsqJbVcqy8n0EroV=nFZoJ_WAr+JbrDf-c1jso856NghC2A@mail.gmail.com>
From:   Krzysztof Kozlowski <krzk@kernel.org>
Date:   Wed, 27 Oct 2021 16:51:56 +0200
Message-ID: <CAJKOXPfDAnECHzGDTisuujT-rGvUqVp4a5WTOQ196yTqwLKHuA@mail.gmail.com>
Subject: Re: [PATCH v2 2/8] dt-bindings: arm: apple: Add apple,pmgr binding
To:     Hector Martin <marcan@marcan.st>
Cc:     Rob Herring <robh@kernel.org>,
        linux-arm-kernel <linux-arm-kernel@lists.infradead.org>,
        Marc Zyngier <maz@kernel.org>, Arnd Bergmann <arnd@kernel.org>,
        Linus Walleij <linus.walleij@linaro.org>,
        Alyssa Rosenzweig <alyssa@rosenzweig.io>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Mark Kettenis <mark.kettenis@xs4all.nl>,
        Philipp Zabel <p.zabel@pengutronix.de>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Johan Hovold <johan@kernel.org>, devicetree@vger.kernel.org,
        "open list:THERMAL" <linux-pm@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        linux-samsung-soc <linux-samsung-soc@vger.kernel.org>,
        "open list:SERIAL DRIVERS" <linux-serial@vger.kernel.org>,
        Mark Kettenis <kettenis@openbsd.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Wed, 27 Oct 2021 at 16:44, Rob Herring <robh@kernel.org> wrote:
>
> On Tue, Oct 26, 2021 at 10:38 PM Hector Martin <marcan@marcan.st> wrote:
> >
> > On 27/10/2021 03.25, Rob Herring wrote:
> > > On Mon, Oct 25, 2021 at 11:47:12PM +0900, Hector Martin wrote:
> > >> +  compatible:
> > >> +    items:
> > >> +      - enum:
> > >> +          - apple,t8103-pmgr
> > >> +          - apple,t8103-minipmgr
> > >> +      - const: apple,pmgr
> > >> +      - const: syscon
> > >> +      - const: simple-mfd
> > >
> > >
> > > 'simple-mfd' means 'there's nothing in this node that any of the child
> > > nodes depend on'. You should be somewhat certain as dropping it later
> > > creates compatibility issues.
> >
> > Hmm, I see simple-mfd turns this into a bus which I guess allows child
> > nodes to be probed without the parent node doing anything special (then
> > we use syscon_node_to_regmap to get the syscon instantiated). Do you
> > have a example use case for doing this without simple-mfd?
>
> Drivers calling of_platform_populate or devm_of_platform_populate.
>
> That of course does mean you need a driver. We could probably make the
> syscon driver call these if needed.
>

Hi Hector,

I thought I mentioned this with your v1, maybe the comment got lost.
We have it for Exynos PMU:
drivers/soc/samsung/exynos-pmu.c
arch/arm/boot/dts/exynos-syscon-restart.dtsi (extending node from
arch/arm/boot/dts/exynos5420.dtsi)
Maybe you can base on that.

Best regards,
Krzysztof