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 Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id F3CBDC28B28 for ; Wed, 12 Mar 2025 20:31:27 +0000 (UTC) Received: from fllvem-ot03.ext.ti.com (fllvem-ot03.ext.ti.com [198.47.19.245]) by mx.groups.io with SMTP id smtpd.web11.5619.1741811482497619769 for ; Wed, 12 Mar 2025 13:31:22 -0700 Authentication-Results: mx.groups.io; dkim=pass header.i=@ti.com header.s=ti-com-17Q1 header.b=EnHd2EAc; spf=pass (domain: ti.com, ip: 198.47.19.245, mailfrom: rs@ti.com) Received: from lelv0266.itg.ti.com ([10.180.67.225]) by fllvem-ot03.ext.ti.com (8.15.2/8.15.2) with ESMTPS id 52CKVB3i1133064 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Wed, 12 Mar 2025 15:31:11 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1741811471; bh=O2iA63UIuPFNMAKqDNiN+kKaHmc6mFHfxj+aP1CT3mE=; h=Date:CC:Subject:From:To:References:In-Reply-To; b=EnHd2EAc3dDzRYA9KnPnehWRgr9A952oWqHSlqm5EFlVpE7S7cPFRgo+BIihu8w0j fB4AdOTbjmb7MrzhEYcsaHlNoLjmA+sIPX15rEEBaJYbRTWe0lujLJ7uVUozrDVhG7 x7whk//O1wTyqoBSltU+CTNp69VlEumnmGsX8rJg= Received: from DLEE110.ent.ti.com (dlee110.ent.ti.com [157.170.170.21]) by lelv0266.itg.ti.com (8.15.2/8.15.2) with ESMTP id 52CKVBGK094319; Wed, 12 Mar 2025 15:31:11 -0500 Received: from DLEE102.ent.ti.com (157.170.170.32) by DLEE110.ent.ti.com (157.170.170.21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23; Wed, 12 Mar 2025 15:31:11 -0500 Received: from lelvsmtp5.itg.ti.com (10.180.75.250) by DLEE102.ent.ti.com (157.170.170.32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23 via Frontend Transport; Wed, 12 Mar 2025 15:31:11 -0500 Received: from localhost (rs-desk.dhcp.ti.com [128.247.81.144]) by lelvsmtp5.itg.ti.com (8.15.2/8.15.2) with ESMTP id 52CKVBhn096128; Wed, 12 Mar 2025 15:31:11 -0500 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="UTF-8" Date: Wed, 12 Mar 2025 15:31:11 -0500 Message-ID: CC: Richard Purdie , , , , , Andrew Davis , Darren Etheridge , Denys Dmytriyenko , Ryan Eatmon , "openembedded-core@lists.openembedded.org" , "Pothukuchi, Vijay" Subject: Re: [oe-core][RFC] Display manager proposal for x11 and wayland From: Randolph Sapp To: Randolph Sapp , Otavio Salvador , X-Mailer: aerc 0.20.1-0-g2ecb8770224a References: <40fd57cb-deaa-480c-8ec6-87ca1a55e21d@ti.com> In-Reply-To: X-C2ProcessedOrg: 333ef613-75bf-4e12-a4b1-8e3623f5dcea List-Id: X-Webhook-Received: from li982-79.members.linode.com [45.33.32.79] by aws-us-west-2-korg-lkml-1.web.codeaurora.org with HTTPS for ; Wed, 12 Mar 2025 20:31:27 -0000 X-Groupsio-URL: https://lists.openembedded.org/g/openembedded-core/message/212729 On Wed Mar 12, 2025 at 12:58 PM CDT, Randolph Sapp wrote: > On Wed Mar 12, 2025 at 5:52 AM CDT, Otavio Salvador wrote: >> Hi Alexander, >> >> I totally get your concerns about long-term maintainability and how addi= ng >> new components to oe-core can complicate things. Still, Randolph's idea >> does make a lot of sense, especially since our current setup has code >> scattered in different places, making it tricky to maintain and potentia= lly >> causing issues down the road. >> >> Checking out Randolph=E2=80=99s proposal, or maybe something similar, co= uld really >> help tidy things up and improve maintainability for oe-core long-term. >> >> Looking forward to hearing more thoughts on this! >> > > Thank you Otavio > >> Em qua., 12 de mar. de 2025 =C3=A0s 06:39, Alexander Kanavin via >> lists.openembedded.org >> escreveu: >> >>> I have a couple of concerns: >>> >>> - can this event handling be achieved simply by using udevadm which is >>> available in any init system? > > Yes and no. Just detecting when a device is registered with the drm subsy= stem > can be achieved with udev though. Udev events for display hotplug events = do not > seem to be easy to identify and cannot be handled without some custom dae= mon > anyway. > > One of our workarounds was to add a rule to make systemd track our main d= ri > device and register a .device unit that we could add as a dependency to t= he > desktop init service. Great for systemd init with a singe device, ignorin= g > hotplug. > > That being said, emptty doesn't support hotplug events right now either, = but I'm > thinking about contributing to that project if people are interested. > >>> - who is the author? What if they abandon the component? We've been >>> reluctant to insert core graphical dependencies (e.g. more interesting >>> compositors than weston) on not widely used things with unclear origin >>> and support promise. > > As far as the author goes, that's fair. This is one of their more popular > repositories and I'm not personally familiar with them. That's always a r= isk > though, and when it comes to lightweight display managers with auto-login > capabilities the only other option is lightdm, which comes with potential > license issues being GPL-3.0. > >>> - can you produce a patchset that showcases the benefits? > > Certainly. Considering our current release window and the bug that brough= t all > this up, I'll have a little demo for Weston I can post in the next few da= ys. I've posted a RFC series for scarthgap showing my proposed solution for weston-init. https://lists.openembedded.org/g/openembedded-core/message/212726 >>> On Wed, 12 Mar 2025 at 01:46, Randolph Sapp via lists.openembedded.org >>> wrote: >>> > >>> > We've recently run into some issues with weston-init attempting to st= art >>> > Weston prior to all drm devices being registered. There's not really = a >>> > good, scriptable mechanism to listen in to device registration events >>> > that works with the existing weston-init package. Well, at least one >>> > that doesn't involve polling files or introducing more dependency on = the >>> > init system being used. >>> > >>> > I also see there is also a lot of scripting around starting X11, >>> > xserver-nodm-init, that (from my limited review) should experience th= e >>> > same issue. >>> > >>> > I'd like to introduce the following display manager for oe-core, empt= ty >>> > [1]. This display manager is, as described upstream, a "Dead simple C= LI >>> > Display Manager on TTY". It supports both x11 and wayland sessions, w= ith >>> > togglable build parameters to completely remove x11 and pam >>> > dependencies. It's licensed MIT, which shouldn't be an issue for any >>> > users. (It is written in Go, if you have opinions about that.) >>> > >>> > With this, both weston-init and the xserver-nodm-init packages can be >>> > re-tuned to leverage this display manager and simply add a user and >>> > emptty config for an autologin session. This can resolve the current >>> > behavior across init systems without additional scripting, and move s= ome >>> > development out of this layer. >>> > >>> > I already have a recipe for emptty, but I figured I would reach out f= or >>> > comment to recent contributors before I submit any patches playing wi= th >>> > the existing init packages. >>> > >>> > [1] https://github.com/tvrzna/emptty >>> > >>> > - Randolph >>> >