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=-14.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,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 C4C47C47083 for ; Wed, 2 Jun 2021 18:08:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AB70061090 for ; Wed, 2 Jun 2021 18:08:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229583AbhFBSKQ (ORCPT ); Wed, 2 Jun 2021 14:10:16 -0400 Received: from mail-ot1-f48.google.com ([209.85.210.48]:46780 "EHLO mail-ot1-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229467AbhFBSKP (ORCPT ); Wed, 2 Jun 2021 14:10:15 -0400 Received: by mail-ot1-f48.google.com with SMTP id 66-20020a9d02c80000b02903615edf7c1aso3211330otl.13; Wed, 02 Jun 2021 11:08:17 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=VYMb7NvZcxWiw7PptXFVUegcgKe65wVgGhLojpylJWs=; b=Z+f4utDPcuM6fprNoNiT+ER3nOUS5ct5KeuwKNHX2AAghkzevE24clBRCFaXiZsmbg p7gH3NglwLEPBxAuFAU7VQwMzHn7DdwJEPEZT137lxzwdHy5s2ZV/3VTykEXICNipum9 ZNj3mPDRNwqG49xUwvzkdpp0E3yW1zStvGRp2eDZF8cof/sksfxR1MihR5f942BIJuIJ 199b999Obnkee6xALzutTIcFa19Up9RrbXk4qkmkjMFI7wv47QNWmIk1kJ/GaQMaO+Id HCnaINycolzE/vkqq5yDWndkK/+2nuNXruxZBjt4PiomL91jIt0+mJvYB2YXqHFcBoqp 3sPA== X-Gm-Message-State: AOAM531gKrp7BSUkGiYsvd2N4FvwLHm7zOD11fiPlCQ+c0QlDP6EmpJq j/JeeGoT0koKTqk4DOCRNQ== X-Google-Smtp-Source: ABdhPJzTkgLV2ppLE4o5GqJG1XKd/A0PrjZETTVCaL15qyF/JiWlCifrnxt/418lRvc/jrVNLNVqWw== X-Received: by 2002:a9d:3644:: with SMTP id w62mr18937060otb.205.1622657296860; Wed, 02 Jun 2021 11:08:16 -0700 (PDT) Received: from robh.at.kernel.org (24-155-109-49.dyn.grandenetworks.net. [24.155.109.49]) by smtp.gmail.com with ESMTPSA id x63sm127364oix.47.2021.06.02.11.08.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 02 Jun 2021 11:08:16 -0700 (PDT) Received: (nullmailer pid 3688828 invoked by uid 1000); Wed, 02 Jun 2021 18:08:14 -0000 Date: Wed, 2 Jun 2021 13:08:13 -0500 From: Rob Herring To: Douglas Anderson Cc: Thierry Reding , dri-devel@lists.freedesktop.org, Stanislav Lisovskiy , Stephen Boyd , robdclark@chromium.org, Bjorn Andersson , Daniel Vetter , David Airlie , Steev Klimaszewski , Neil Armstrong , Maarten Lankhorst , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Jonas Karlman , Lyude Paul , Sam Ravnborg , Linus W , linux-arm-msm@vger.kernel.org, Laurent Pinchart , Rob Herring , Andrzej Hajda Subject: Re: [PATCH v8 02/11] dt-bindings: drm: Introduce the DP AUX bus Message-ID: <20210602180813.GA3688734@robh.at.kernel.org> References: <20210525000159.3384921-1-dianders@chromium.org> <20210524165920.v8.2.Id3c048d22e72a9f90084a543b5b4e3f43bc9ab62@changeid> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210524165920.v8.2.Id3c048d22e72a9f90084a543b5b4e3f43bc9ab62@changeid> Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Mon, 24 May 2021 17:01:50 -0700, Douglas Anderson wrote: > We want to be able to list an eDP panel as a child of an eDP > controller node to represent the fact that the panel is connected to > the controller's DP AUX bus. Though the panel and the controller are > connected in several ways, the DP AUX bus is the primary control > interface between the two and thus makes the most sense to model in > device tree hierarchy. > > Listing a panel in this way makes it possible for the panel driver to > easily get access to the DP AUX bus that it resides on, which can be > useful to help in auto-detecting the panel and for turning on various > bits. > > NOTE: historically eDP panels were _not_ listed under their controller > but were listed at the top level of the device tree. This will still > be supported for backward compatibility (and while DP controller > drivers are adapted to support the new DT syntax) but should be > considered deprecated since there is no downside to listing the panel > under the controller. > > For now, the DP AUX bus bindings will only support an eDP panel > underneath. It's possible it could be extended to allow having a DP > connector under it in the future. > > The idea for this bus's design was hashed out over IRC [1]. > > [1] https://people.freedesktop.org/~cbrill/dri-log/?channel=dri-devel&date=2021-05-11 > > Signed-off-by: Douglas Anderson > --- > My DT yaml-fu is still weak. If I did something stupid, please help me > learn how to do this better! > > NOTE: there is no "Example" in this bindings file. Yikes! This is > because I wanted to keep this patch separate from the one that enables > the first eDP controller. See the patch ("dt-bindings: drm/aux-bus: > Add an example") for the example. > > ALSO: if anyone else would like to be listed as a "Maintainer" in this > file then please shout! > > Changes in v8: > - Separate DP AUX bus binding is new for v8. > > .../bindings/display/dp-aux-bus.yaml | 37 +++++++++++++++++++ > 1 file changed, 37 insertions(+) > create mode 100644 Documentation/devicetree/bindings/display/dp-aux-bus.yaml > Reviewed-by: Rob Herring