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=-20.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,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 5217DC4707F for ; Thu, 27 May 2021 15:53:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 303EA6124C for ; Thu, 27 May 2021 15:53:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233887AbhE0PzJ (ORCPT ); Thu, 27 May 2021 11:55:09 -0400 Received: from perceval.ideasonboard.com ([213.167.242.64]:40272 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233886AbhE0PzI (ORCPT ); Thu, 27 May 2021 11:55:08 -0400 Received: from pendragon.ideasonboard.com (62-78-145-57.bb.dnainternet.fi [62.78.145.57]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 89058163F; Thu, 27 May 2021 17:53:32 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1622130812; bh=2exOXygmzDfmGJrjMDBCl0yc7PGP3854X0J7CpX7VC4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=aB2Duh+2uQG5LmpnlXcqdTJWBUAYofKiDRUoObA+tSy/0YlIhPrBcvZ3DuA9aQ95k chPnXG4o01bwWGJKSkl8Jgw4VDgStM9zRxxQqGz8hNJh9Dna0QkMwG/t88lK17l95L J5mldeZZmPnCEDE/laYnUS/f/mnR6a+k20uXEBPU= Date: Thu, 27 May 2021 18:53:26 +0300 From: Laurent Pinchart To: Maxime Ripard Cc: dri-devel@lists.freedesktop.org, Daniel Vetter , David Airlie , Maarten Lankhorst , Thomas Zimmermann , linux-doc@vger.kernel.org, Jonathan Corbet , Alexandre Belloni , Alexandre Torgue , Alex Deucher , Alison Wang , Alyssa Rosenzweig , Andrew Jeffery , Andrzej Hajda , Anitha Chrisanthus , Benjamin Gaignard , Ben Skeggs , Boris Brezillon , Brian Starkey , Chen Feng , Chen-Yu Tsai , Christian Gmeiner , Christian =?utf-8?B?S8O2bmln?= , Chun-Kuang Hu , Edmund Dea , Eric Anholt , Fabio Estevam , Gerd Hoffmann , Haneen Mohammed , Hans de Goede , Heiko =?utf-8?Q?St=C3=BCbner?= , Huang Rui , Hyun Kwon , Inki Dae , Jani Nikula , Jernej Skrabec , Jerome Brunet , Joel Stanley , John Stultz , Jonas Karlman , Jonathan Hunter , Joonas Lahtinen , Joonyoung Shim , Jyri Sarha , Kevin Hilman , Kieran Bingham , Krzysztof Kozlowski , Kyungmin Park , Linus Walleij , Liviu Dudau , Lucas Stach , Ludovic Desroches , Marek Vasut , Martin Blumenstingl , Matthias Brugger , Maxime Coquelin , Melissa Wen , Neil Armstrong , Nicolas Ferre , Noralf =?utf-8?Q?Tr=C3=B8nnes?= , NXP Linux Team , Oleksandr Andrushchenko , Patrik Jakobsson , Paul Cercueil , Pengutronix Kernel Team , Philippe Cornu , Philipp Zabel , Qiang Yu , Rob Clark , Robert Foss , Rob Herring , Rodrigo Siqueira , Rodrigo Vivi , Roland Scheidegger , Russell King , Sam Ravnborg , Sandy Huang , Sascha Hauer , Sean Paul , Seung-Woo Kim , Shawn Guo , Stefan Agner , Steven Price , Sumit Semwal , Thierry Reding , Tian Tao , Tomeu Vizoso , Tomi Valkeinen , VMware Graphics , Xinliang Liu , Xinwei Kong , Yannick Fertre , Zack Rusin , Daniel Vetter Subject: Re: [PATCH v2] Documentation: gpu: Mention the requirements for new properties Message-ID: References: <20210520142435.267873-1-maxime@cerno.tech> <20210525103940.chay5r3ns4alowvc@gilmour> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20210525103940.chay5r3ns4alowvc@gilmour> Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org Hi Maxime, On Tue, May 25, 2021 at 12:39:40PM +0200, Maxime Ripard wrote: > On Mon, May 24, 2021 at 07:04:43AM +0300, Laurent Pinchart wrote: > > On Thu, May 20, 2021 at 04:24:35PM +0200, Maxime Ripard wrote: > > > New KMS properties come with a bunch of requirements to avoid each > > > driver from running their own, inconsistent, set of properties, > > > eventually leading to issues like property conflicts, inconsistencies > > > between drivers and semantics, etc. > > > > > > Let's document what we expect. > > > > > > Cc: Alexandre Belloni > > > Cc: Alexandre Torgue > > > Cc: Alex Deucher > > > Cc: Alison Wang > > > Cc: Alyssa Rosenzweig > > > Cc: Andrew Jeffery > > > Cc: Andrzej Hajda > > > Cc: Anitha Chrisanthus > > > Cc: Benjamin Gaignard > > > Cc: Ben Skeggs > > > Cc: Boris Brezillon > > > Cc: Brian Starkey > > > Cc: Chen Feng > > > Cc: Chen-Yu Tsai > > > Cc: Christian Gmeiner > > > Cc: "Christian König" > > > Cc: Chun-Kuang Hu > > > Cc: Edmund Dea > > > Cc: Eric Anholt > > > Cc: Fabio Estevam > > > Cc: Gerd Hoffmann > > > Cc: Haneen Mohammed > > > Cc: Hans de Goede > > > Cc: "Heiko Stübner" > > > Cc: Huang Rui > > > Cc: Hyun Kwon > > > Cc: Inki Dae > > > Cc: Jani Nikula > > > Cc: Jernej Skrabec > > > Cc: Jerome Brunet > > > Cc: Joel Stanley > > > Cc: John Stultz > > > Cc: Jonas Karlman > > > Cc: Jonathan Hunter > > > Cc: Joonas Lahtinen > > > Cc: Joonyoung Shim > > > Cc: Jyri Sarha > > > Cc: Kevin Hilman > > > Cc: Kieran Bingham > > > Cc: Krzysztof Kozlowski > > > Cc: Kyungmin Park > > > Cc: Laurent Pinchart > > > Cc: Linus Walleij > > > Cc: Liviu Dudau > > > Cc: Lucas Stach > > > Cc: Ludovic Desroches > > > Cc: Marek Vasut > > > Cc: Martin Blumenstingl > > > Cc: Matthias Brugger > > > Cc: Maxime Coquelin > > > Cc: Maxime Ripard > > > Cc: Melissa Wen > > > Cc: Neil Armstrong > > > Cc: Nicolas Ferre > > > Cc: "Noralf Trønnes" > > > Cc: NXP Linux Team > > > Cc: Oleksandr Andrushchenko > > > Cc: Patrik Jakobsson > > > Cc: Paul Cercueil > > > Cc: Pengutronix Kernel Team > > > Cc: Philippe Cornu > > > Cc: Philipp Zabel > > > Cc: Qiang Yu > > > Cc: Rob Clark > > > Cc: Robert Foss > > > Cc: Rob Herring > > > Cc: Rodrigo Siqueira > > > Cc: Rodrigo Vivi > > > Cc: Roland Scheidegger > > > Cc: Russell King > > > Cc: Sam Ravnborg > > > Cc: Sandy Huang > > > Cc: Sascha Hauer > > > Cc: Sean Paul > > > Cc: Seung-Woo Kim > > > Cc: Shawn Guo > > > Cc: Stefan Agner > > > Cc: Steven Price > > > Cc: Sumit Semwal > > > Cc: Thierry Reding > > > Cc: Tian Tao > > > Cc: Tomeu Vizoso > > > Cc: Tomi Valkeinen > > > Cc: VMware Graphics > > > Cc: Xinliang Liu > > > Cc: Xinwei Kong > > > Cc: Yannick Fertre > > > Cc: Zack Rusin > > > Reviewed-by: Daniel Vetter > > > Signed-off-by: Maxime Ripard > > > > > > --- > > > > > > Changes from v2: > > > - Typos and wording reported by Daniel and Alex > > > --- > > > Documentation/gpu/drm-kms.rst | 19 +++++++++++++++++++ > > > 1 file changed, 19 insertions(+) > > > > > > diff --git a/Documentation/gpu/drm-kms.rst b/Documentation/gpu/drm-kms.rst > > > index 87e5023e3f55..c28b464dd397 100644 > > > --- a/Documentation/gpu/drm-kms.rst > > > +++ b/Documentation/gpu/drm-kms.rst > > > @@ -463,6 +463,25 @@ KMS Properties > > > This section of the documentation is primarily aimed at user-space developers. > > > For the driver APIs, see the other sections. > > > > > > +Requirements > > > +------------ > > > + > > > +KMS drivers might need to add extra properties to support new features. > > > +Each new property introduced in a driver need to meet a few > > > > s/need/needs/ > > > > > +requirements, in addition to the one mentioned above.: > > > > s/above./above/ > > > > > + > > > +- It must be standardized, with some documentation to describe how the > > > + property can be used. > > > + > > > +- It must provide a generic helper in the core code to register that > > > + property on the object it attaches to. > > > + > > > +- Its content must be decoded by the core and provided in the object's > > > + associated state structure. That includes anything drivers might want to > > > + precompute, like :c:type:`struct drm_clip_rect ` for planes. > > > > Does this effectively mean that we completely forbid driver-specific > > properties ? While I agree that we should strive for standardization, > > there are two issues that worry me. The first one is simple, we may need > > to control features that would be very device-specific, and > > standardizing properties doesn't seem to make much sense in that case. > > I'd say that we should make it clear in that case that it's > driver-specific. > > > The second issue relates to properties that could be applicable to > > multiple devices, but for which we have a single driver. Designing a > > standard with a single data point usually leads to a bad design. I'm not > > sure how to handle this correctly though, as we certainly don't want > > this to be taken as an excuse to create driver-specific properties when > > generic properties would make sense. > > The discussion that made us create that patch was about this property: > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/gpu/drm/sti/sti_hdmi.c#n170 > > It's all kind of bad: > - It kind of conflicts with the generic Colorspace property > - It's not really a colorspace (Not that "Colorspace" is either) > - It could have been made generic from the start > - We don't have any knowledge on who uses it and why, so it's > difficult to rework > > This was introduced before we had any kind of rule or documentation on > the UAPI though, so there's no-one to blame really but we don't really > want to have something like that happen again. > > I agree that doing something generic from the beginning can be > difficult, but this is some userspace API that we will have to carry > around forever, so it's worth it I guess? It is, no disagreement about that. Pushing driver authors to explore standardization of properties is a good idea. As long as we have a pragmatic approach and allow vendor-specific properties when it makes sense, I'll have no concern. > You have a point on the vendor properties though. Maybe we can require a > vendor prefix for those? It would reduce the risk of a conflict. I like the idea of a vendor prefix. -- Regards, Laurent Pinchart 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=-18.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 D57E1C47089 for ; Thu, 27 May 2021 15:53:37 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 45741613C9 for ; Thu, 27 May 2021 15:53:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 45741613C9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 769356F41E; Thu, 27 May 2021 15:53:36 +0000 (UTC) Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4CEF46F41E for ; Thu, 27 May 2021 15:53:35 +0000 (UTC) Received: from pendragon.ideasonboard.com (62-78-145-57.bb.dnainternet.fi [62.78.145.57]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 89058163F; Thu, 27 May 2021 17:53:32 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1622130812; bh=2exOXygmzDfmGJrjMDBCl0yc7PGP3854X0J7CpX7VC4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=aB2Duh+2uQG5LmpnlXcqdTJWBUAYofKiDRUoObA+tSy/0YlIhPrBcvZ3DuA9aQ95k chPnXG4o01bwWGJKSkl8Jgw4VDgStM9zRxxQqGz8hNJh9Dna0QkMwG/t88lK17l95L J5mldeZZmPnCEDE/laYnUS/f/mnR6a+k20uXEBPU= Date: Thu, 27 May 2021 18:53:26 +0300 From: Laurent Pinchart To: Maxime Ripard Subject: Re: [PATCH v2] Documentation: gpu: Mention the requirements for new properties Message-ID: References: <20210520142435.267873-1-maxime@cerno.tech> <20210525103940.chay5r3ns4alowvc@gilmour> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20210525103940.chay5r3ns4alowvc@gilmour> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Xinliang Liu , dri-devel@lists.freedesktop.org, Anitha Chrisanthus , Jonathan Hunter , Jerome Brunet , Kevin Hilman , Ludovic Desroches , NXP Linux Team , Sascha Hauer , Roland Scheidegger , Sean Paul , Hyun Kwon , Andrew Jeffery , Seung-Woo Kim , Noralf =?utf-8?Q?Tr=C3=B8nnes?= , Pengutronix Kernel Team , Alex Deucher , Alexandre Belloni , linux-doc@vger.kernel.org, David Airlie , Edmund Dea , Thierry Reding , Daniel Vetter , Krzysztof Kozlowski , Steven Price , VMware Graphics , Ben Skeggs , Martin Blumenstingl , Rodrigo Siqueira , Boris Brezillon , Sandy Huang , Kyungmin Park , Maxime Coquelin , Haneen Mohammed , Neil Armstrong , Melissa Wen , Gerd Hoffmann , Benjamin Gaignard , Sam Ravnborg , Jonathan Corbet , Xinwei Kong , Chen-Yu Tsai , Alyssa Rosenzweig , Joel Stanley , Chun-Kuang Hu , Jonas Karlman , Chen Feng , Alison Wang , Rodrigo Vivi , Tomeu Vizoso , Tomi Valkeinen , Kieran Bingham , Tian Tao , Shawn Guo , Christian =?utf-8?B?S8O2bmln?= , Daniel Vetter , Liviu Dudau , Alexandre Torgue , Paul Cercueil , Andrzej Hajda , Huang Rui , Marek Vasut , Joonyoung Shim , Oleksandr Andrushchenko , Russell King , Philippe Cornu , Thomas Zimmermann , Hans de Goede , Matthias Brugger , Jernej Skrabec , Yannick Fertre , Nicolas Ferre , Robert Foss , Qiang Yu , Jyri Sarha Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi Maxime, On Tue, May 25, 2021 at 12:39:40PM +0200, Maxime Ripard wrote: > On Mon, May 24, 2021 at 07:04:43AM +0300, Laurent Pinchart wrote: > > On Thu, May 20, 2021 at 04:24:35PM +0200, Maxime Ripard wrote: > > > New KMS properties come with a bunch of requirements to avoid each > > > driver from running their own, inconsistent, set of properties, > > > eventually leading to issues like property conflicts, inconsistencies > > > between drivers and semantics, etc. > > > > > > Let's document what we expect. > > > > > > Cc: Alexandre Belloni > > > Cc: Alexandre Torgue > > > Cc: Alex Deucher > > > Cc: Alison Wang > > > Cc: Alyssa Rosenzweig > > > Cc: Andrew Jeffery > > > Cc: Andrzej Hajda > > > Cc: Anitha Chrisanthus > > > Cc: Benjamin Gaignard > > > Cc: Ben Skeggs > > > Cc: Boris Brezillon > > > Cc: Brian Starkey > > > Cc: Chen Feng > > > Cc: Chen-Yu Tsai > > > Cc: Christian Gmeiner > > > Cc: "Christian König" > > > Cc: Chun-Kuang Hu > > > Cc: Edmund Dea > > > Cc: Eric Anholt > > > Cc: Fabio Estevam > > > Cc: Gerd Hoffmann > > > Cc: Haneen Mohammed > > > Cc: Hans de Goede > > > Cc: "Heiko Stübner" > > > Cc: Huang Rui > > > Cc: Hyun Kwon > > > Cc: Inki Dae > > > Cc: Jani Nikula > > > Cc: Jernej Skrabec > > > Cc: Jerome Brunet > > > Cc: Joel Stanley > > > Cc: John Stultz > > > Cc: Jonas Karlman > > > Cc: Jonathan Hunter > > > Cc: Joonas Lahtinen > > > Cc: Joonyoung Shim > > > Cc: Jyri Sarha > > > Cc: Kevin Hilman > > > Cc: Kieran Bingham > > > Cc: Krzysztof Kozlowski > > > Cc: Kyungmin Park > > > Cc: Laurent Pinchart > > > Cc: Linus Walleij > > > Cc: Liviu Dudau > > > Cc: Lucas Stach > > > Cc: Ludovic Desroches > > > Cc: Marek Vasut > > > Cc: Martin Blumenstingl > > > Cc: Matthias Brugger > > > Cc: Maxime Coquelin > > > Cc: Maxime Ripard > > > Cc: Melissa Wen > > > Cc: Neil Armstrong > > > Cc: Nicolas Ferre > > > Cc: "Noralf Trønnes" > > > Cc: NXP Linux Team > > > Cc: Oleksandr Andrushchenko > > > Cc: Patrik Jakobsson > > > Cc: Paul Cercueil > > > Cc: Pengutronix Kernel Team > > > Cc: Philippe Cornu > > > Cc: Philipp Zabel > > > Cc: Qiang Yu > > > Cc: Rob Clark > > > Cc: Robert Foss > > > Cc: Rob Herring > > > Cc: Rodrigo Siqueira > > > Cc: Rodrigo Vivi > > > Cc: Roland Scheidegger > > > Cc: Russell King > > > Cc: Sam Ravnborg > > > Cc: Sandy Huang > > > Cc: Sascha Hauer > > > Cc: Sean Paul > > > Cc: Seung-Woo Kim > > > Cc: Shawn Guo > > > Cc: Stefan Agner > > > Cc: Steven Price > > > Cc: Sumit Semwal > > > Cc: Thierry Reding > > > Cc: Tian Tao > > > Cc: Tomeu Vizoso > > > Cc: Tomi Valkeinen > > > Cc: VMware Graphics > > > Cc: Xinliang Liu > > > Cc: Xinwei Kong > > > Cc: Yannick Fertre > > > Cc: Zack Rusin > > > Reviewed-by: Daniel Vetter > > > Signed-off-by: Maxime Ripard > > > > > > --- > > > > > > Changes from v2: > > > - Typos and wording reported by Daniel and Alex > > > --- > > > Documentation/gpu/drm-kms.rst | 19 +++++++++++++++++++ > > > 1 file changed, 19 insertions(+) > > > > > > diff --git a/Documentation/gpu/drm-kms.rst b/Documentation/gpu/drm-kms.rst > > > index 87e5023e3f55..c28b464dd397 100644 > > > --- a/Documentation/gpu/drm-kms.rst > > > +++ b/Documentation/gpu/drm-kms.rst > > > @@ -463,6 +463,25 @@ KMS Properties > > > This section of the documentation is primarily aimed at user-space developers. > > > For the driver APIs, see the other sections. > > > > > > +Requirements > > > +------------ > > > + > > > +KMS drivers might need to add extra properties to support new features. > > > +Each new property introduced in a driver need to meet a few > > > > s/need/needs/ > > > > > +requirements, in addition to the one mentioned above.: > > > > s/above./above/ > > > > > + > > > +- It must be standardized, with some documentation to describe how the > > > + property can be used. > > > + > > > +- It must provide a generic helper in the core code to register that > > > + property on the object it attaches to. > > > + > > > +- Its content must be decoded by the core and provided in the object's > > > + associated state structure. That includes anything drivers might want to > > > + precompute, like :c:type:`struct drm_clip_rect ` for planes. > > > > Does this effectively mean that we completely forbid driver-specific > > properties ? While I agree that we should strive for standardization, > > there are two issues that worry me. The first one is simple, we may need > > to control features that would be very device-specific, and > > standardizing properties doesn't seem to make much sense in that case. > > I'd say that we should make it clear in that case that it's > driver-specific. > > > The second issue relates to properties that could be applicable to > > multiple devices, but for which we have a single driver. Designing a > > standard with a single data point usually leads to a bad design. I'm not > > sure how to handle this correctly though, as we certainly don't want > > this to be taken as an excuse to create driver-specific properties when > > generic properties would make sense. > > The discussion that made us create that patch was about this property: > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/gpu/drm/sti/sti_hdmi.c#n170 > > It's all kind of bad: > - It kind of conflicts with the generic Colorspace property > - It's not really a colorspace (Not that "Colorspace" is either) > - It could have been made generic from the start > - We don't have any knowledge on who uses it and why, so it's > difficult to rework > > This was introduced before we had any kind of rule or documentation on > the UAPI though, so there's no-one to blame really but we don't really > want to have something like that happen again. > > I agree that doing something generic from the beginning can be > difficult, but this is some userspace API that we will have to carry > around forever, so it's worth it I guess? It is, no disagreement about that. Pushing driver authors to explore standardization of properties is a good idea. As long as we have a pragmatic approach and allow vendor-specific properties when it makes sense, I'll have no concern. > You have a point on the vendor properties though. Maybe we can require a > vendor prefix for those? It would reduce the risk of a conflict. I like the idea of a vendor prefix. -- Regards, Laurent Pinchart