Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752947AbZK3ReX (ORCPT ); Mon, 30 Nov 2009 12:34:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752863AbZK3ReW (ORCPT ); Mon, 30 Nov 2009 12:34:22 -0500 Received: from mx1.redhat.com ([209.132.183.28]:60632 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752318AbZK3ReV (ORCPT ); Mon, 30 Nov 2009 12:34:21 -0500 Message-ID: <4B140200.9020503@redhat.com> Date: Mon, 30 Nov 2009 15:33:52 -0200 From: Mauro Carvalho Chehab User-Agent: Thunderbird 2.0.0.22 (X11/20090609) MIME-Version: 1.0 To: kevin granade CC: Andy Walls , Ray Lee , Maxim Levitsky , Alan Cox , Jon Smirl , Krzysztof Halasa , Christoph Bartelmus , dmitry.torokhov@gmail.com, j@jannau.net, jarod@redhat.com, jarod@wilsonet.com, linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, stefanr@s5r6.in-berlin.de, superm1@ubuntu.com Subject: Re: [RFC] What are the goals for the architecture of an in-kernel IR system? References: <9e4733910911280937k37551b38g90f4a60b73665853@mail.gmail.com> <1259469121.3125.28.camel@palomino.walls.org> <20091129124011.4d8a6080@lxorguk.ukuu.org.uk> <1259515703.3284.11.camel@maxim-laptop> <2c0942db0911290949p89ae64bjc3c7501c2de6930c@mail.gmail.com> <1259537732.5231.11.camel@palomino.walls.org> <4B13B2FA.4050600@redhat.com> <1259585852.3093.31.camel@palomino.walls.org> <4B13C799.4060906@redhat.com> <7004b08e0911300814tb474f96s42ec56ca2e43cf7a@mail.gmail.com> In-Reply-To: <7004b08e0911300814tb474f96s42ec56ca2e43cf7a@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1972 Lines: 45 kevin granade wrote: > On Mon, Nov 30, 2009 at 7:24 AM, Mauro Carvalho Chehab > wrote: > >> After the boot, a device can open the raw API, disabling any in-kernel >> decoding/handling and handle IR directly. Alternatively, an udev rule >> can load a different keymap based on some config written on a file. > > This idea of the in-kernel decoding being disabled when the raw API is > opened worries me. What guarantees that the following scenario will > not happen? > > User uses apps which retrieve the decoded IR messages from the kernel. > User installs an app which decodes messages via the raw API (not lirc). > User's other applications no longer receive IR messages. > > I know the assumption has been that "only lirc will use the raw API", > but this seems like a poor assumption for an API design to me. All those questions are theoretical, as we haven't a raw API code already merged in kernel. So, this is just my understanding on how this should work. If the user wants to use the raw interface, it is because the in-kernel decoding is not appropriate for his usage (at least while such application is opened). So, not disabling the evdev output seems senseless. Btw, this is the same behavior that happens when some application directly opens an evdev interface, instead of letting it to be redirected to stdin. > A related question, what is an application developer who wishes to > decode the raw IR signal (for whatever reason) to do? Are they > *required* to implement full decoding and feed all the messages back > to the kernel so they don't break other applications? If such application won't do it, the IR will stop working, while the application is in use. Cheers, Mauro. -- 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/