From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6FC11C2BB54 for ; Tue, 7 Apr 2020 11:03:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 515702078A for ; Tue, 7 Apr 2020 11:03:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728054AbgDGLDo (ORCPT ); Tue, 7 Apr 2020 07:03:44 -0400 Received: from relay9-d.mail.gandi.net ([217.70.183.199]:48821 "EHLO relay9-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726591AbgDGLDo (ORCPT ); Tue, 7 Apr 2020 07:03:44 -0400 X-Originating-IP: 78.193.40.249 Received: from kb-xps (unknown [78.193.40.249]) (Authenticated sender: kamel.bouhara@bootlin.com) by relay9-d.mail.gandi.net (Postfix) with ESMTPSA id D5839FF819; Tue, 7 Apr 2020 11:03:40 +0000 (UTC) Date: Tue, 7 Apr 2020 13:03:39 +0200 From: Kamel Bouhara To: Maxime Ripard Cc: Dmitry Torokhov , William Breathitt Gray , Rob Herring , Mark Rutland , Nicolas Ferre , Alexandre Belloni , Ludovic Desroches , linux-arm-kernel@lists.infradead.org, Thomas Petazzoni , linux-input@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org Subject: Re: [PATCH 2/3] Input: rotary-encoder-counter: add DT bindings Message-ID: <20200407110339.GA1489441@kb-xps> References: <20200406155806.1295169-1-kamel.bouhara@bootlin.com> <20200406155806.1295169-3-kamel.bouhara@bootlin.com> <20200407094159.xtbhtsxorvs2g22c@gilmour.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200407094159.xtbhtsxorvs2g22c@gilmour.lan> Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Tue, Apr 07, 2020 at 11:41:59AM +0200, Maxime Ripard wrote: > Hi Kamel, > Hi Maxime, > The prefix for device tree bindings is usually dt-bindings: > $framework: $title > > So a title like "dt-bindings: input: Add a counter-based rotary > encoder binding" would be better. > OK, to be fixed then. > On Mon, Apr 06, 2020 at 05:58:05PM +0200, Kamel Bouhara wrote: > > Add dt binding for the counter variant of the rotary encoder driver. > > > > Signed-off-by: Kamel Bouhara > > --- > > .../input/rotary-encoder-counter.yaml | 67 +++++++++++++++++++ > > 1 file changed, 67 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/input/rotary-encoder-counter.yaml > > > > diff --git a/Documentation/devicetree/bindings/input/rotary-encoder-counter.yaml b/Documentation/devicetree/bindings/input/rotary-encoder-counter.yaml > > new file mode 100644 > > index 000000000000..a59f7c1faf0c > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/input/rotary-encoder-counter.yaml > > @@ -0,0 +1,67 @@ > > +# SPDX-License-Identifier: GPL-2.0 > > Bindings are usually used by other OS's, so you should consider > putting it under a more permissive license, usually that would be GPL2 > and the BSD-2-Clause > Well to be honest I just looked into an existing binding and I guess the wrong one :). > > +%YAML 1.2 > > +--- > > +$id: http://devicetree.org/schemas/input/rotary-encoder-counter.yaml# > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > + > > +title: Rotary Encoder Counter > > + > > +maintainers: > > + - Kamel Bouhara > > + > > +description: > > + Registers a Rotary encoder connected through a counter device. > > You shouldn't really describe the action here, but more what the > binding is about. The registration will not depend on the presence of > the node following that binding, but rather on whether or not the OS > that uses it has support for it. > Then shall it be better with just : "A rotary encoder device using a generic counter interface." ? > > +properties: > > + compatible: > > + const: rotary-encoder-counter > > + > > + counter: > > + description: Phandle for the counter device providing rotary position. > > This should have a type > > > + linux-axis: > > + description: The input subsystem axis to map to this rotary encoder. > > + type: boolean > > + > > + qdec-mode: > > + description: | > > + Quadrature decoder function to set in the counter device. > > + 3: x1-PHA > > + 4: x1-PHB > > + 5: x2-PHA > > + 6: x2-PHB > > + 7: x4-PHA and PHB > > That range (even though it's a bit odd) should be expressed through an > enum so that you can check that the values are actually within that > range. > Indeed, that make sens to check it from the binding. Will fix it in v2. > > + steps: > > + description: Number of steps in a full turnaround of the encoder. > > Muli-line strings should have either quotes around them, or a | or > > like you did for the description. | will keep the \n, > will make that > a single string. > > This should also have a type > > > + Only relevant for absolute axis. > > This should be expressed through a if / then clause, or a dependencies one > > > Defaults to 24 which is a typical > > + value for such devices. > > This should be expressed through a default property. > The devil is in the details and yet quite lot of them to fix. Thanks. > > + relative-axis: > > + description: Register a relative axis rather than an absolute one. > > + type: boolean > > + > > + rollover: > > + description: Automatic rollover when the rotary value becomes greater > > + than the specified steps or smaller than 0. For absolute axis only. > > + type: boolean > > Same story than steps for the dependency. Also, what is is the > behaviour when this property isn't set? > OK, if rollover isn't set then the count is unbounded, of course this shall be described here. > > + poll-interval: > > + description: Poll interval at which the position is read from the counter > > + device (default 500ms). > > It should have a type too, and a default property > > > + > > +required: > > + - compatible > > + - counter > > + - qdec-mode > > + > > +examples: > > + - | > > + rotary@0 { > > + compatible = "rotary-encoder-counter"; > > A unit-address (the part after @) only makes sense for a node if > there's a matching reg property in the node. This will trigger a DTC > warning, so you should remove the @0 > Ok I'll fix it then. Thanks again. > Maxime -- Kamel Bouhara, Bootlin Embedded Linux and kernel engineering https://bootlin.com