From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Chris Brandt Subject: RE: [PATCH 2/2] dt-bindings: pinctrl: Add RZ/A2 pinctrl and GPIO Date: Wed, 17 Oct 2018 00:53:40 +0000 Message-ID: References: <20181005150951.22129-1-chris.brandt@renesas.com> <20181005150951.22129-3-chris.brandt@renesas.com> <20181016224700.GA26385@bogus> In-Reply-To: <20181016224700.GA26385@bogus> Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 To: Rob Herring Cc: Linus Walleij , Mark Rutland , Geert Uytterhoeven , jacopo mondi , "linux-gpio@vger.kernel.org" , "devicetree@vger.kernel.org" , "linux-renesas-soc@vger.kernel.org" List-ID: On Tuesday, October 16, 2018, Rob Herring wrote: > > +Optional properties: > > + - gpio-controller > > + Include this in order to enable GPIO functionality. When included, > both > > + gpio_cells and gpio_ranges are then required. > > + - #gpio-cells > > + Must be 2 > > + - gpio-ranges > > + Expresses the total number GPIO ports/pins in this SoC >=20 > Are these really optional? I guess in theory a board could use no GPIOs, > but that seems unlikely. They are 'optional' in the sense that if you don't include them in the=20 DT, the driver still loads (just without any GPIO, but pinctrl still=20 works). So, I was just documenting that fact. If you think I should just move these to required, let me know an I'm=20 fine with that. (as in, DT documents HW, not software) > > +Sub-nodes > > +--------- > > + > > +The child nodes of the pin controller node describe a pin multiplexing > > +function or a GPIO controller alternatively. >=20 > But the parent is already a GPIO controller. This needs to be fully > defined. Now that I read this, I think my wording was off (I was borrowing text=20 for other files). How about this: The child nodes of the pin controller designate pins to be used for specific peripheral functions or as GPIO. Chris