From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benoit Parrot Subject: Re: [Patch v3 2/2] gpio: Document GPIO hogging mechanism Date: Wed, 10 Dec 2014 16:50:06 -0600 Message-ID: <20141210225006.GA13407@ti.com> References: <1417726922-10376-1-git-send-email-bparrot@ti.com> <1417726922-10376-3-git-send-email-bparrot@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-gpio-owner@vger.kernel.org To: Alexandre Courbot Cc: Linus Walleij , "linux-gpio@vger.kernel.org" , Linux Kernel Mailing List , "devicetree@vger.kernel.org" , Maxime Ripard , Jiri Prchal , Pantelis Antoniou List-Id: devicetree@vger.kernel.org Alexandre Courbot wrote on Wed [2014-Dec-10 19:56:17 +0900]: > On Fri, Dec 5, 2014 at 6:02 AM, Benoit Parrot wrote: > > Add GPIO hogging documentation to gpio.txt > > > > Signed-off-by: Benoit Parrot > > --- > > Changes since v2: > > * Updated to the latest hog syntax. > > > > Changes since v1: > > * Split the devicetree bindings documentation in its own patch. > > > > Documentation/devicetree/bindings/gpio/gpio.txt | 23 +++++++++++++++++++++++ > > 1 file changed, 23 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt b/Documentation/devicetree/bindings/gpio/gpio.txt > > index 3fb8f53..6d88133 100644 > > --- a/Documentation/devicetree/bindings/gpio/gpio.txt > > +++ b/Documentation/devicetree/bindings/gpio/gpio.txt > > @@ -103,6 +103,22 @@ Every GPIO controller node must contain both an empty "gpio-controller" > > property, and a #gpio-cells integer property, which indicates the number of > > cells in a gpio-specifier. > > > > +The GPIO chip may contain GPIO hog definitions. GPIO hogging is a mechanism > > +providing automatic GPIO request and configuration as part of the > > +gpio-controller's driver probe function. > > + > > +Each GPIO hog definition is represented as a child node of the GPIO controller. > > +Required properties: > > +- gpio-hog: A property specifying that this child node represent a gpio-hog. > > +- gpios: Store the gpio information (id, flags, ...). Shall contain the > > + number of cells specified in its parent node (GPIO controller > > + node). > > Since this property will only describe one GPIO, why use the plural > form? Would it not be confusing? I would tend to agree in this case but based on this original comment from Linus on this thread: http://marc.info/?l=linux-gpio&m=138917388625221&w=2 where on 08/01/2014 10:37, Linus Walleij wrote: > +Each GPIO hog definition is represented as a child node of the GPIO controller. > +Required properties: > +- gpio: store the gpio informations (id, flags, ...). Shall contain the > + number of cells specified in its parent node (GPIO controller node). This property is alway plural "gpios". As long as everyone agree, I am fine with it. > > > +- direction: A property specifying the direction/value needed. This property > > + can take the folowing values: input, output-high, output-low. > > nit: since this property not only describes the direction but also the > (potential) value, I suggest to rename it to "state". Since you are the one who suggested "direction" in the first place, as long as you agree with yourself :)