From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from galahad.ideasonboard.com ([185.26.127.97]:50765 "EHLO galahad.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750939AbaI3VAx (ORCPT ); Tue, 30 Sep 2014 17:00:53 -0400 From: Laurent Pinchart To: Boris Brezillon Cc: Thierry Reding , dri-devel@lists.freedesktop.org, David Airlie , Mauro Carvalho Chehab , linux-media@vger.kernel.org, Guennadi Liakhovetski , linux-kernel@vger.kernel.org, Hans Verkuil Subject: Re: [PATCH v2 1/5] video: move mediabus format definition to a more standard place Date: Wed, 01 Oct 2014 00:00:50 +0300 Message-ID: <15186053.Jni2YnBHkN@avalon> In-Reply-To: <20140930114423.3a171aa9@bbrezillon> References: <1411999363-28770-1-git-send-email-boris.brezillon@free-electrons.com> <20140930083952.GA4059@ulmo> <20140930114423.3a171aa9@bbrezillon> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-media-owner@vger.kernel.org List-ID: Hi Boris, On Tuesday 30 September 2014 11:44:23 Boris Brezillon wrote: > On Tue, 30 Sep 2014 10:39:53 +0200 Thierry Reding wrote: > > On Tue, Sep 30, 2014 at 09:37:57AM +0200, Boris Brezillon wrote: > >> On Mon, 29 Sep 2014 23:41:09 +0300 Laurent Pinchart wrote: > > > > [...] > > > >>> Incidentally, patch 2/5 in this series is missing a documentation > >>> update ;-) > >> > >> Yep, regarding this patch, I wonder if it's really necessary to add > >> new formats to the v4l2_mbus_pixelcode enum. > >> If we want to move to this new common definition (across the video > >> related subsytems), we should deprecate the old enum > >> v4l2_mbus_pixelcode, and this start by not adding new formats, don't > >> you think ? > > > > I agree in general, but I think it could prove problematic in practice. > > If somebody wants to use one of the new codes but is using the V4L2 enum > > they have a problem. > > > > That said, given that there is now a unified enum people will hopefully > > start converting drivers to it instead. > > I'm more worried about user-space lib/programs as this header is part > of the uapi... > > But let's be optimistic here and keep porting new formats to > v4l2_mbus_pixelcode enum ;-). I think we should try to keep the two in sync, until we can remove the v4l2_mbus_pixelcode enum (I know, I'm being utopian here). However, I really want all pixel codes to be properly documented, regardless of whether we add them to v4l2_mbus_pixelcode or not. > Anyway, I still don't know where to put the documentation. Dropping a > new video format doc without any context (I mean subdev-formats.xml is > included in media documentation, but there's no generic video doc yet) > is a bit weird... Now that's a good question. We could start a generic video docbook documentation. As I expect more infrastructure to be shared between V4L2 and DRM (and, who knows, FBDEV...) over time, I think that would be a good move. However docbook doesn't seem to be in the DRM developers' good books, so this might be frown upon. We could also use a plain text, kerneldoc-like format for the common documentation, but the formats would then disappear from the V4L2 documentation, which isn't a very good idea. For that reason I would favour docbook. I've CC'ed Hans Verkuil who might want to share his opinion on the matter. -- Regards, Laurent Pinchart