From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 28DC632FA1B for ; Tue, 14 Apr 2026 06:49:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776149372; cv=none; b=kikgfubp8KwEAxFW0ZM9l65lVLcdo4fiEBmeshjVmPX4DPTyamlqquovM7v6tes8bhkPACVWyxQJXm5QxZyavHxg7wf+Zen7Xwd6ZZc+3VQqs6dJufK3/069OseYFhjUaJJBD0lIsV7loDrRpfGhNkAUG7XklgaiyPg6H2iMCnM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776149372; c=relaxed/simple; bh=4QcqPIPKZyanVqQSJdDIz7tkwsobDHIZF/mNzGHc4v8=; h=Message-ID:Date:MIME-Version:From:Subject:To:Cc:References: In-Reply-To:Content-Type; b=qWHjKutR+B6/DkbDwaj2SR9gIk0oEXlrnpJ4pyxKciMaHaySyylWFTQfS092fpVGNQ6vOoeYGjVnIu+ArMQcYj5i0r1F75gn3JlXgSpV4xW2APlTnOzltWnlMt+BA1jEIYUSXOEbIWwaUCuKsyRGxW7KpeeyEMaNz1GAVl2qVo8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=emhjCLsg; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="emhjCLsg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A6F3AC19425; Tue, 14 Apr 2026 06:49:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776149371; bh=4QcqPIPKZyanVqQSJdDIz7tkwsobDHIZF/mNzGHc4v8=; h=Date:From:Subject:To:Cc:References:In-Reply-To:From; b=emhjCLsge5kic/E20ByK/p6VzCogwnz+SNNEGSD0qLAmOMeFp9io1Hr5558C1p5wn y603fs84IN2wT//rUTaGZNN/cMK3fmCH6NodA3bdOtAo5k5JmP6s6G9cPC0N8y2PU7 khixSIfB9G3W+TXSB/c/uVLKsAe7DpnXiJDj4BJWw8ZFqjKBzpxe1i2Oa2qkEiLvMo 8t5PypVu0H/7qK1A1D0znqEir/0RgcYOAcarSlPBGfnr5odNyRmT23iT4MLk9C1EyS LGRcl3uZ1lNZX/NAROjqmiwj3GrKgJy3ihiP2HjK8ePI7FdGueBgL6GZ+v9+o/61zI JdhM8pZVnyBLA== Message-ID: <2df51d19-5408-4dea-98ac-24bf3473d45b@kernel.org> Date: Tue, 14 Apr 2026 08:49:23 +0200 Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: Hans Verkuil Subject: Re: [ANNv4] Media Summit on May 26th in Nice, France To: Michael Riesch , Linux Media Mailing List Cc: Mauro Carvalho Chehab , Laurent Pinchart , Sean Young , Sakari Ailus , Ricardo Ribalda , Nicolas Dufresne , Jacopo Mondi , =?UTF-8?Q?Niklas_S=C3=B6derlund?= , Tomi Valkeinen , Alain Volmat , Bryan O'Donoghue , Dave Stevenson , Daniel Almeida , Michael Tretter , Tomasz Figa , Steve Cho , Kieran Bingham , Kevin Hilman , Paul Kocialkowski , Benjamin Mugnier , Hans de Goede , Maxime Ripard , Brandon Brnich , Marco Felsch , Loic Poulain , =?UTF-8?Q?Sven_P=C3=BCschel?= , Devarsh Thakkar , Yemike Abhilash Chandra , Jackson Lee , Jai Luthra , Mehdi Djait , "Padhi, Beleswar" , "Donadkar, Rishikesh" , Rouven Czerwinski References: <0f95419b-93c1-4c4f-873b-43bd2a9853f7@kernel.org> <756a634a-9699-4118-90e1-4ce06844c369@collabora.com> Content-Language: en-US, nl In-Reply-To: <756a634a-9699-4118-90e1-4ce06844c369@collabora.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 13/04/2026 11:57, Michael Riesch wrote: > Hi Hans, > > On 4/12/26 12:25, Hans Verkuil wrote: >> [...] >> Agenda (tentative): >> >> 8:45-9:20: Arrive, settle in >> >> 9:20-9:30: Short intro (Hans Verkuil) >> >> 9:30-9:45: Status of ISP support in V4L2 >> Presenter: Laurent Pinchart >> Description: Summary of ISP-related development in V4L2 since the last >> Linux Media Summit. This includes a brief overview of technical >> developments, and a summary of the efforts to engage with vendors. >> >> 9:45-10:45: V4L2 Stateless Video Encoding uAPI Progress Update >> Presenter: Paul Kocialkowski >> Description: An update on the ongonig work to support stateless codecs in V4L2. >> Some of the remaining open topics will be presented and discussed. >> >> 10:45-11:00: break >> >> 11:00-11:30: Vulkan Video Codecs >> Presenter: Nicolas Dufresne >> Description: Vulkan video codecs: what are the viable options for Linux Media >> and what is in preparation outside of our subsystem. The second aspect is >> informative as these discussions don't seem to lean toward our subsystem as the >> foundation. But I think it's rather useful for everyone to understand why and >> what is included. >> >> 11:30-12:00: Protected Video playback on i.MX8MQ >> Presenter: Rouven Czerwinski >> Description: Introduction to protected video playback >> on i.MX8MQ and missing bits for linux-media & protected heap interoperability. >> >> 12:00-13:30: Lunch >> >> 13:30-14:00: HDCP support for HDMI receivers >> Presenter: Hans Verkuil >> Description: I have been working on adding HDCP support for HDMI receivers. >> Specifically the HDCP negotiation between sources and sinks. >> >> 14:00-14:30: AI patches >> Presenter: Sakari Ailus >> Description: What is our policy w.r.t. AI generated patches? >> >> 14:30-15:00 Overview of Media CI: where do pipelines run? >> Presenter: Ricardo Ribalda >> Description: How are jobs in pipelines assigned? How does the infrastructure >> for Media CI work? Are there things that can be tweaked to make it more >> reliable? >> >> 15:00-15:15: Break >> >> 15:15-16:15: Discussion of the media subsystem development process >> Presenter: Hans Verkuil >> Description: Review of the multi-committer model: current status and next steps. >> Are there any bottlenecks, any ideas for improvements, w.r.t. the development process? >> >> As you can see, there is still some available time for other topics. > > If there is still a bit of time left, maybe we can reserve some 15-30 > minutes for the following: I added this to the agenda. Thanks! Regards, Hans > > -------%<---snip-------------------------------------------------------- > > The Butterfly Effect or How Support for Complex Hardware may affect the uAPI > > Video capture and camera hardware in recent SoCs is exceedingly complex > and the assumption that there is one central V4L2 driver that registers > the media device does not necessarily hold anymore. IMHO we need a > central media device to rule them all and adaptations to the > v4l2_{async,device}_register_subdev code. The discussion [0, 1] quickly > escalated: > - Dynamic (de)registration of media entities is desired > - This requires considerations about the uAPI > - There is significant overlap with the notion of fault-tolerant V4L2 > - There is also a ton of cleanup work, but the resulting patches must > not break anything existing > - So we need to talk about possible migration strategies in order to > achieve reasonable progress without interfering too much with > existing and working parts > > TL;DR: This short talk outlines the effects of upstreaming Rockchip > RK3588 video capture and camera support on the V4L2/MC uAPI and on the > (linux-media) universe as we know it today. > > [0] > https://linuxtv.org/irc/oftc/irclogger_log/linux-media?date=2026-02-17,Tue&sel=72#l68 > [1] > https://linuxtv.org/irc/oftc/irclogger_log/linux-media?date=2026-02-18,Wed&sel=14#l10 > > -------%<---snip-------------------------------------------------------- > > If desired, I'll try to find the time to describe the issue in more > detail on the list *before* everyone travels to Nice. Then, we can use > the time on site more effectively to discuss it. > > Best regards, > Michael