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=-16.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 6F116C433B4 for ; Thu, 20 May 2021 13:25:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 467E561019 for ; Thu, 20 May 2021 13:25:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231737AbhETN0m (ORCPT ); Thu, 20 May 2021 09:26:42 -0400 Received: from mail.kernel.org ([198.145.29.99]:48036 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231733AbhETN0m (ORCPT ); Thu, 20 May 2021 09:26:42 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id D44566135A; Thu, 20 May 2021 13:25:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1621517120; bh=ZGR0d1utfxvQm3s0niYerfupf8fQvgD1F1Vf6QEpFTQ=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=IXW65ZzioDVPpl+gzUyMI7M0QoFYoDQ0n55Jigm9jcR1TrXz764f5RO555kqg1dgS +59mcs5flYcU+0f1rFAoFe9rsMmFbdg6NdLm97gxNtobggpXUyFZrdolLMEiypJY5E cKA3ALOxntTIfnBmr94MP95KzRU7w2Qj4WyArEzPGceHu6fcpBcJSUAzuhQEjeBIC0 HCw/kXVbZsToel77d5YBHK4zxdRsL9rbmbT6u1XtU4j4JiCqI9OMV5lsQbSElz+NJ/ sU4yw79M9FHu5fq9GK62cYcRgvw6/MUSq8M0chxk840k/b5ooVe+7hT0pbretYqesF MjgN9G723EnIw== Received: by mail-ej1-f45.google.com with SMTP id i7so7449408ejc.5; Thu, 20 May 2021 06:25:20 -0700 (PDT) X-Gm-Message-State: AOAM53030A9e5BQg0z0iBIVmjylPcFjc9VRSAWkjfT7X7/XH8knMDu3/ RFXWKnG0wf6rD3wgU4NpBylvngu/JHaHhi0T6g== X-Google-Smtp-Source: ABdhPJyYRw8Cvw8jFOxekcPR1d+Gtnv+Q16LLY5HiWSVWHW/5gWy/2iRMsHIUVSQpFkOEVzkI/Xk0CeumJ0LRI12PjY= X-Received: by 2002:a17:907:724b:: with SMTP id ds11mr4688567ejc.108.1621517119203; Thu, 20 May 2021 06:25:19 -0700 (PDT) MIME-Version: 1.0 References: <20210517200907.1459182-1-dianders@chromium.org> <20210517130450.v7.3.I98bf729846c37c4c143f6ab88b1e299280e2fe26@changeid> <20210519200156.GA3535665@robh.at.kernel.org> In-Reply-To: From: Rob Herring Date: Thu, 20 May 2021 08:25:06 -0500 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v7 03/10] dt-bindings: drm/bridge: ti-sn65dsi86: Add aux-bus child To: Doug Anderson Cc: Andrzej Hajda , Neil Armstrong , Laurent Pinchart , Jonas Karlman , Sam Ravnborg , Stanislav Lisovskiy , Lyude Paul , Thierry Reding , Stephen Boyd , Bjorn Andersson , linux-arm-msm , Maarten Lankhorst , Linus W , dri-devel , Rob Clark , Steev Klimaszewski , Daniel Vetter , David Airlie , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , LKML Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Wed, May 19, 2021 at 4:06 PM Doug Anderson wrote: > > Hi, > > On Wed, May 19, 2021 at 1:02 PM Rob Herring wrote: > > > > On Mon, May 17, 2021 at 01:09:00PM -0700, Douglas Anderson wrote: > > > We want to be able to list an eDP panel as a child of a ti-sn65dsi86 > > > node to represent the fact that the panel is connected to the bridge's > > > DP AUX bus. Though the panel and the bridge chip 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: it's still possible to continue using the bridge chip and point > > > to a panel that _isn't_ listed as a child of the bridge chip (since > > > it's worked that way previously), but that should be deprecated since > > > there is no downside to listing the panel under the bridge chip. > > > > > > 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 > > > --- > > > Possibly we might want something fancier that could be included by > > > other eDP controller bindings. If we want to do this, I'd love to be > > > pointed at a good example to follow. > > > > > > Changes in v7: > > > - ti-sn65dsi86: Add aux-bus child patch new for v7. > > > > > > .../bindings/display/bridge/ti,sn65dsi86.yaml | 22 ++++++++++++++++++- > > > 1 file changed, 21 insertions(+), 1 deletion(-) > > > > > > diff --git a/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi86.yaml b/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi86.yaml > > > index 26932d2e86ab..51f5a29e216c 100644 > > > --- a/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi86.yaml > > > +++ b/Documentation/devicetree/bindings/display/bridge/ti,sn65dsi86.yaml > > > @@ -70,6 +70,11 @@ properties: > > > const: 1 > > > description: See ../../pwm/pwm.yaml for description of the cell formats. > > > > > > + aux-bus: > > > > As this is a node: > > > > type: object > > > > > + description: > > > + It is recommended that you place your panel under the aux-bus node > > > + here to represent the control hierarchy. > > > + > > > ports: > > > $ref: /schemas/graph.yaml#/properties/ports > > > > > > @@ -201,11 +206,26 @@ examples: > > > > > > port@1 { > > > reg = <1>; > > > - endpoint { > > > + sn65dsi86_out: endpoint { > > > remote-endpoint = <&panel_in_edp>; > > > }; > > > }; > > > }; > > > + > > > + aux-bus { > > > + panel { > > > > We should perhaps have a separate aux-bus schema. > > Yeah. Before spending lots of time digging into how to do this I > wanted to see if anyone was going to give me a big-old NAK on the > whole approach. ;-) > > I guess I'd make a file called "dp-aux-bus.yaml" (maybe right under > bindings/display?) and then I'd include it like this: > > aux-bus: > $ref: "../dp-aux-bus.yaml#" Right. > > Something should > > define the child node is 'panel' and nothing else. > > At the moment the code also requires that the node name is 'aux-bus'. > Any objections to that? No. There's 2 ways to do that. The above does and adding $nodename in dp-aux-bus.yaml will. The latter also means the schema will be applied automatically to any node named 'aux-bus'. That means the schema will be applied twice unless you have 'select: false'. The main advantage of the latter case is it gets applied even without all the users converted to schema. > > Though perhaps > > connectors are valid too? > > They might be. We could always add it later? Sure. Rob