From patchwork Wed Jun 14 06:30:16 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen-Yu Tsai X-Patchwork-Id: 775617 Return-Path: X-Original-To: incoming-dt@patchwork.ozlabs.org Delivered-To: patchwork-incoming-dt@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3wncFW13qbz9s7m for ; Wed, 14 Jun 2017 16:30:23 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750764AbdFNGaV (ORCPT ); Wed, 14 Jun 2017 02:30:21 -0400 Received: from mirror2.csie.ntu.edu.tw ([140.112.30.76]:54706 "EHLO wens.csie.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750757AbdFNGaU (ORCPT ); Wed, 14 Jun 2017 02:30:20 -0400 Received: by wens.csie.org (Postfix, from userid 1000) id F1FBC60062; Wed, 14 Jun 2017 14:30:16 +0800 (CST) From: Chen-Yu Tsai To: Maxime Ripard , David Airlie , Rob Herring , Mark Rutland Cc: Chen-Yu Tsai , dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] dt-bindings: display: sunxi: Improve endpoint ID scheme readability Date: Wed, 14 Jun 2017 14:30:16 +0800 Message-Id: <20170614063016.22069-1-wens@csie.org> X-Mailer: git-send-email 2.11.0 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org The explanation for the endpoint ID numbering scheme is convoluted and hard to understand. This patch aims to improve the readability of it by combining the existing two paragraphs, while also providing a diagram example, and how endpoints should be numbered based on that example. Signed-off-by: Chen-Yu Tsai Acked-by: Rob Herring --- Hope this helps. I'm not sure I can improve this even more without spelling out all cases. --- .../bindings/display/sunxi/sun4i-drm.txt | 36 ++++++++++++++++------ 1 file changed, 27 insertions(+), 9 deletions(-) diff --git a/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt b/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt index b83e6018041d..70885041553a 100644 --- a/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt +++ b/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt @@ -4,15 +4,33 @@ Allwinner A10 Display Pipeline The Allwinner A10 Display pipeline is composed of several components that are going to be documented below: -For the input port of all components up to the TCON in the display -pipeline, if there are multiple components, the local endpoint IDs -must correspond to the index of the upstream block. For example, if -the remote endpoint is Frontend 1, then the local endpoint ID must -be 1. - -Conversely, for the output ports of the same group, the remote endpoint -ID must be the index of the local hardware block. If the local backend -is backend 1, then the remote endpoint ID must be 1. +For all connections between components up to the TCONs in the display +pipeline, when there are multiple components of the same type at the +same depth, the local endpoint ID must be the same as the remote +component's index. For example, if the remote endpoint is Frontend 1, +then the local endpoint ID must be 1. + + Frontend 0 [0] ----------- [0] Backend 0 [0] ----- [0] TCON 0 + [1] ---- ---- [1] + \ / + X + / \ + [0] ---- ---- [0] + Frontend 1 [1] ----------- [1] Backend 1 [0] ----- [0] TCON 1 + +For a two pipeline system such as the one depicted above, the lines +represent the connections between the components, while the numbers +within the square brackets corresponds to the ID of the local endpoint. + +The same rule also applies to DE 2.0 mixer-TCON connections: + + Mixer 0 [0] ----------- [0] TCON 0 + [1] ---- ---- [1] + \ / + X + / \ + [0] ---- ---- [0] + Mixer 1 [1] ----------- [1] TCON 1 HDMI Encoder ------------