Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934401Ab3FSLNy (ORCPT ); Wed, 19 Jun 2013 07:13:54 -0400 Received: from mail-out.m-online.net ([212.18.0.10]:35412 "EHLO mail-out.m-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933666Ab3FSLNw (ORCPT ); Wed, 19 Jun 2013 07:13:52 -0400 X-Auth-Info: w9paaWJizYVWchzDb36eu6K/sJ80/D2QkjPwen2h118= Date: Wed, 19 Jun 2013 13:13:41 +0200 From: Gerhard Sittig To: Chao Xie Cc: Marek Vasut , stefan@openezx.org, Eric Miao , Arnd Bergmann , slapin@ossfans.org, Dmitry Torokhov , "linux-kernel@vger.kernel.org" , Haojian Zhuang , Chao Xie , laforge@openezx.org, linux-input@vger.kernel.org, sleep_walker@suse.cz, Robert Jarzmik , drwyrm@gmail.com, "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH V3 5/5] input: pxa27x-keypad: add device tree support Message-ID: <20130619111341.GH2426@book.gsilab.sittig.org> Mail-Followup-To: Chao Xie , Marek Vasut , stefan@openezx.org, Eric Miao , Arnd Bergmann , slapin@ossfans.org, Dmitry Torokhov , "linux-kernel@vger.kernel.org" , Haojian Zhuang , Chao Xie , laforge@openezx.org, linux-input@vger.kernel.org, sleep_walker@suse.cz, Robert Jarzmik , drwyrm@gmail.com, "linux-arm-kernel@lists.infradead.org" References: <1371527778-5236-1-git-send-email-chao.xie@marvell.com> <1371527778-5236-6-git-send-email-chao.xie@marvell.com> <201306191022.51630.marex@denx.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: DENX Software Engineering GmbH User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2946 Lines: 66 On Wed, Jun 19, 2013 at 16:38 +0800, Chao Xie wrote: > > On Wed, Jun 19, 2013 at 4:22 PM, Marek Vasut wrote: > > > >> Signed-off-by: Chao Xie > >> [ ... ] > >> +++ b/Documentation/devicetree/bindings/input/pxa27x-keypad.txt > >> @@ -0,0 +1,60 @@ > >> +* Marvell PXA Keypad controller > >> + > >> +Required Properties > >> +- compatible : should be "marvell,pxa27x-keypad" > >> +- reg : Address and length of the register set for the device > >> +- interrupts : The interrupt for the keypad controller > >> +- marvell,debounce-interval : How long time the key will be > > > > Is there no generic prop name for this debounce interval? > > > I searched at drivers/input and Documents. > Two drivers use "debounce-interval", gpio-keys.c and stmpe-keypad.c. > They describe the meanings of "debounce-interval" at its own document file. > Some other drivers uses "xxx,debounce-delay-ms" or "debounce-delay-ms" > So it seems that there is no generic prop name for this debounce interval. Actually there is, but under a different (more user friendly) name: See the 'debounce-delay-ms' property in Documentation/devicetree/bindings/input/gpio-matrix-keypad.txt which gets referenced in the matrix_keypad_parse_dt() routine in the drivers/input/keyboard/matrix_keypad.c source file. Ah, your last sentence mentions that fact. But when you introduce DT support into an existing driver which previously used platform data, then there is no problem with backwards compatibility in .dts files. So I suggest to go with the "debounce-delay-ms" name since it better reflects to the .dts author (hardware engineer) which unit the number is supposed to be specified in. Note that I've recently worked on extending the matrix keypad input driver (doc improvements, software polling, binary encoded column selection), but haven't submitted the patch series yet since it's perfectly operational on the target which motivated the extension but wasn't tested yet on any other platform or matrix setup -- I currently lack access to an ARM based board with either lots of accessible GPIOs to connect a matrix to, or some matrix already built into the board, but more importantly lack free resources for this very driver extension. Alternatively I might send an RFC series since the current state isn't good enough for v1. Just ask if you'd like to test or review what I have come up with so far (it builds but wasn't run-tested). virtually yours Gerhard Sittig -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr. 5, D-82194 Groebenzell, Germany Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: office@denx.de -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/