Re: [PATCH 3/3] dt-bindings: gpio: pcf857x: Convert to json-schema

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Rob Herring <robh@kernel.org>
Cc: "Linus Walleij" <linus.walleij@linaro.org>,
	"Laurent Pinchart" <laurent.pinchart+renesas@ideasonboard.com>,
	"Bartosz Golaszewski" <bgolaszewski@baylibre.com>,
	"Benoît Cousson" <bcousson@baylibre.com>,
	"Tony Lindgren" <tony@atomide.com>,
	"Jan Tuerk" <jan.tuerk@emtrion.com>,
	"Shawn Guo" <shawnguo@kernel.org>,
	"open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS"
	<devicetree@vger.kernel.org>,
	"open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
	Linux-OMAP <linux-omap@vger.kernel.org>,
	"Linux ARM" <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH 3/3] dt-bindings: gpio: pcf857x: Convert to json-schema
Date: Thu, 27 May 2021 17:04:19 +0200	[thread overview]
Message-ID: <CAMuHMdWvK6+GybGKc0MBn3qxJk_JQ8dOe1-3vfiezeZmNmzkxQ@mail.gmail.com> (raw)
In-Reply-To: <20210521182403.GA50332@robh.at.kernel.org>

Hi Rob,

On Fri, May 21, 2021 at 8:24 PM Rob Herring <robh@kernel.org> wrote:
> On Fri, May 21, 2021 at 12:23:47PM +0200, Geert Uytterhoeven wrote:
> > On Fri, May 21, 2021 at 12:04 PM Linus Walleij <linus.walleij@linaro.org> wrote:
> > > On Fri, May 21, 2021 at 9:54 AM Geert Uytterhoeven
> > > <geert+renesas@glider.be> wrote:
> > > > Convert the PCF857x-compatible I/O expanders Device Tree binding
> > > > documentation to json-schema.
> > > >
> > > > Document missing compatible values, properties, and gpio hogs.
> > > >
> > > > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> > >
> > > (...)
> > > > Perhaps the "ti,pcf8575" construct should be removed, and the few users
> > > > fixed instead?
> > >
> > > You would rather list it as deprecated I think?
> > > It is ABI...
> >
> > All DTS files use the "nxp,pcf8575" fallback, except for
> > arch/x86/platform/ce4100/falconfalls.dts.
> > The latter ain't working with Linux, as the Linux driver doesn't
> > match against "ti,pcf8575"...

Correction: i2c_device_id-based matching ignores the vendor part
of the compatible value.  One day this is gonna bite us...

> Perhaps can it just be removed?

I think so.  All other users of similar I2C GPIO expanders just
use the compatible values of the original NXP parts.

> > > > +patternProperties:
> > > > +  "^(hog-[0-9]+|.+-hog(-[0-9]+)?)$":
> > > > +    type: object
> > >
> > > But this is already in
> > > /dtschema/schemas/gpio/gpio-hog.yaml
> > > for nodename, isn't that where it properly belongs?
> > >
> > > I'm however confused here Rob will know what to do.
>
> This one is a bit odd.
>
> > If we leave this out, something still has to refer to it?
> > I see no other binding doing that...
>
> It's selected by 'gpio-hog' being present, but here you need to make
> sure that's the case.

OK. Fixed.

> And I would hope you could define the node name to be just 1 of the 2
> cases.

Yep, the latter is fine.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds