From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752752AbcFVVWO (ORCPT ); Wed, 22 Jun 2016 17:22:14 -0400 Received: from zencphosting06.zen.co.uk ([82.71.204.9]:50814 "EHLO zencphosting06.zen.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751905AbcFVVWN (ORCPT ); Wed, 22 Jun 2016 17:22:13 -0400 Subject: Re: [PATCH v4 2/9] [media] v4l2-core: Add VFL_TYPE_TOUCH_SENSOR To: Florian Echtler References: <1466172988-3698-1-git-send-email-nick.dyer@itdev.co.uk> <1466172988-3698-3-git-send-email-nick.dyer@itdev.co.uk> <5767DAE4.3000202@xs4all.nl> <576A7B03.30206@butterbrot.org> <02dea636-03a0-6c45-3c7e-7b01868a0f32@itdev.co.uk> Cc: Hans Verkuil , Dmitry Torokhov , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, Benjamin Tissoires , Benson Leung , Alan Bowens , Javier Martinez Canillas , Chris Healy , Henrik Rydberg , Andrew Duggan , James Chen , Dudley Du , Andrew de los Reyes , sheckylin@chromium.org, Peter Hutterer , mchehab@osg.samsung.com From: Nick Dyer Message-ID: <4acb15eb-7e05-5cfa-5524-afd8ee546a53@itdev.co.uk> Date: Wed, 22 Jun 2016 22:22:03 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.1.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-OutGoing-Spam-Status: No, score=-0.1 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - zencphosting06.zen.co.uk X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - itdev.co.uk X-Get-Message-Sender-Via: zencphosting06.zen.co.uk: authenticated_id: nick.dyer@itdev.co.uk X-Authenticated-Sender: zencphosting06.zen.co.uk: nick.dyer@itdev.co.uk Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 22/06/2016 21:38, Florian Echtler wrote: > On Wed, 22 Jun 2016, Nick Dyer wrote: > >> On 22/06/2016 12:48, Florian Echtler wrote: >>> On 20.06.2016 14:00, Hans Verkuil wrote: >>>> On 06/17/2016 04:16 PM, Nick Dyer wrote: >>>>> >>>>> Use a new device prefix v4l-touch for these devices, to stop generic >>>>> capture software from treating them as webcams. >> >>> Come to think of it, wouldn't it make sense to expose the other touch >>> devices as generic frame grabbers, too, so you can easily view the debug >>> output with any generic tool like cheese? >> >> While I like the idea of being able to use the generic tools, I think we >> needed to do something to stop these devices turning up in e.g. video >> conferencing software - it would cause a lot of confusion. There's nothing >> stopping particular tools adding the necessary code to handle touch devices >> if they feel their users want it. > > Just to clarify: from the userspace point-of-view, would this change simply > modify the prefix of the device node (i.e. /dev/video1 -> /dev/v4l-touch1), > or would it somehow affect the API? If it's just the device node name, then > that shouldn't be a problem after all, because e.g. reacTIVision requires > you to specify the exact camera to be used anyway. With the changes that Hans Verkuil has asked me to do: * The device node is /dev/v4l-touch0-255 * There are several new formats eg. V4L2_TCH_FMT_DELTA_TD16 (16 bit deltas) * I've defined new types VFL_TYPE_TOUCH, V4L2_BUF_TYPE_TOUCH_CAPTURE, V4L2_INPUT_TYPE_TOUCH We're just testing the changes, I hope to post an updated version soon.