Re: [PATCH v2 01/15] dt-bindings: gpio: convert bindings for NXP PCA953x family to dtschema

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Krzysztof Kozlowski <krzk@kernel.org>
Cc: "Nishanth Menon" <nm@ti.com>,
	"Linus Walleij" <linus.walleij@linaro.org>,
	"Bartosz Golaszewski" <bgolaszewski@baylibre.com>,
	"Rob Herring" <robh+dt@kernel.org>,
	"Benoît Cousson" <bcousson@baylibre.com>,
	"Tony Lindgren" <tony@atomide.com>,
	"Russell King" <linux@armlinux.org.uk>,
	"Jason Cooper" <jason@lakedaemon.net>,
	"Andrew Lunn" <andrew@lunn.ch>,
	"Gregory Clement" <gregory.clement@bootlin.com>,
	"Sebastian Hesselbarth" <sebastian.hesselbarth@gmail.com>,
	"Joel Stanley" <joel@jms.id.au>,
	"Andrew Jeffery" <andrew@aj.id.au>,
	"Shawn Guo" <shawnguo@kernel.org>,
	"Sascha Hauer" <s.hauer@pengutronix.de>,
	"Pengutronix Kernel Team" <kernel@pengutronix.de>,
	"NXP Linux Team" <linux-imx@nxp.com>,
	"Matthias Brugger" <matthias.bgg@gmail.com>,
	"Geert Uytterhoeven" <geert+renesas@glider.be>,
	"Magnus Damm" <magnus.damm@gmail.com>,
	"Tero Kristo" <t-kristo@ti.com>,
	"Michal Simek" <michal.simek@xilinx.com>,
	"Guenter Roeck" <linux@roeck-us.net>,
	"open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS"
	<devicetree@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"open list:TI ETHERNET SWITCH DRIVER (CPSW)"
	<linux-omap@vger.kernel.org>,
	"Linux ARM" <linux-arm-kernel@lists.infradead.org>,
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	linux-mediatek@lists.infradead.org,
	Linux-Renesas <linux-renesas-soc@vger.kernel.org>
Subject: Re: [PATCH v2 01/15] dt-bindings: gpio: convert bindings for NXP PCA953x family to dtschema
Date: Fri, 11 Sep 2020 08:41:52 +0200	[thread overview]
Message-ID: <CAMuHMdVG6+BsTUxb4wcAwj1WK982S0k2RCxmb3x9gsOS2TphNw@mail.gmail.com> (raw)
In-Reply-To: <CAJKOXPdQJz7aLu4sjds46SiZwxvB-VMBR=stjpUme+8iEo+d-w@mail.gmail.com>

Hi Krzysztof,

On Thu, Sep 10, 2020 at 8:54 PM Krzysztof Kozlowski <krzk@kernel.org> wrote:
> On Thu, 10 Sep 2020 at 20:28, Nishanth Menon <nm@ti.com> wrote:
> > On 19:57-20200910, Krzysztof Kozlowski wrote:
> > [...]
> > > +  wakeup-source:
> > > +    $ref: /schemas/types.yaml#/definitions/flag
> > > +
> > > +patternProperties:
> > > +  "^(hog-[0-9]+|.+-hog(-[0-9]+)?)$":
> >
> > I wonder if "hog" is too generic and might clash with "something-hog" in
> > the future?
>
> This pattern is already used in
> Documentation/devicetree/bindings/gpio/fsl-imx-gpio.yaml. It will
> match only children and so far it did not find any other nodes in ARM
> and ARM64 dts. I don't expect clashes. Also the question is then - if
> one adds a child of GPIO expander named "foobar-hog" and it is not a
> GPIO hog, then what is it?

Perhaps you didn't find any other nodes as children of pca953x
controllers?
There are other hog nodes in other types of GPIO controllers. Typically
they're named after the purpose, e.g. "wifi-disable", "i2c3_mux_oe_n",
"pcie_sata_switch", "lcd0_mux".

IMHO it's a hog if it contains a "gpio-hog" property, regardless of node
naming.

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