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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 F26ECC10F00 for ; Fri, 6 Mar 2020 09:42:14 +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 CC96A20866 for ; Fri, 6 Mar 2020 09:42:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CC96A20866 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 575936ECB0; Fri, 6 Mar 2020 09:42:14 +0000 (UTC) Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by gabe.freedesktop.org (Postfix) with ESMTPS id 413856ECAA; Fri, 6 Mar 2020 09:42:13 +0000 (UTC) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 06 Mar 2020 01:42:12 -0800 X-IronPort-AV: E=Sophos;i="5.70,521,1574150400"; d="scan'208";a="234747642" Received: from jnikula-mobl3.fi.intel.com (HELO localhost) ([10.237.66.161]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 06 Mar 2020 01:42:03 -0800 From: Jani Nikula To: Rajat Jain In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20200305012338.219746-1-rajatja@google.com> <20200305012338.219746-3-rajatja@google.com> <87o8tbnnqa.fsf@intel.com> Date: Fri, 06 Mar 2020 11:42:00 +0200 Message-ID: <87tv31om53.fsf@intel.com> MIME-Version: 1.0 Subject: Re: [Intel-gfx] [PATCH v6 2/3] drm/i915: Lookup and attach ACPI device node for connectors X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Sean Paul , David Airlie , Sugumaran Lacshiminarayanan , dri-devel , Daniel Thompson , Jonathan Corbet , Mark Pearson , Tomoki Maruichi , Rajat Jain , intel-gfx@lists.freedesktop.org, Maxime Ripard , Mat King , Duncan Laurie , Greg Kroah-Hartman , Linux Kernel Mailing List , Pavel Machek , Nitin Joshi1 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Thu, 05 Mar 2020, Rajat Jain wrote: > On Thu, Mar 5, 2020 at 1:41 AM Jani Nikula wrote: >> >> On Wed, 04 Mar 2020, Rajat Jain wrote: >> 1) See if we can postpone creating and attaching properties to connector >> ->late_register hook. (I didn't have the time to look into it yet, at >> all.) > > Apparently not. The drm core doesn't like to add properties in > late_register() callback. I just tried it and get this warning: I kind of had a feeling this would be the case, thanks for checking. >> 2) Provide a way to populate connector->acpi_device_id and >> connector->acpi_handle on a per-connector basis. At least the device id >> remains constant for the lifetime of the drm_device > > Are you confirming that the connector->acpi_device_id remains constant > for the lifetime of the drm_device, as calculated in > intel_acpi_device_id_update()? Even in the face of external displays > (monitors) being connected and disconnected during the lifetime of the > system? If so, then I think we can have a solution. First I thought so. Alas it does not hold for DP MST, where you can have connectors added and removed dynamically. I think we could ensure they stay the same for all other connectors though. I'm pretty sure this is already the case; they get added/removed after all others. Another thought, from the ACPI perspective, I'm not sure the dynamically added/removed DP MST connectors should even have acpi handles. But again, tying all this together with ACPI stuff is not something I am an expert on. >> (why do we keep >> updating it at every resume?!) but can we be sure ->acpi_handle does >> too? (I don't really know my way around ACPI.) > > I don't understand why this was being updated on every resume in that > case (this existed even before my patchset). I believe we do not need > it. Yes, the ->acpi_handle will not change if the ->acpi_device_id > does not change. I believe the way forward should then be to populate > connector->acpi_device_id and connector->acpi_handle ONE TIME at the > time of connector init (and not update it on every resume). Does this > sound ok? If a DP MST connector gets removed, should the other ACPI display indexes after that shift, or remain the same? I really don't know. BR, Jani. -- Jani Nikula, Intel Open Source Graphics Center _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx