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=-6.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 81186C433E3 for ; Wed, 19 Aug 2020 10:12:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 65994207FF for ; Wed, 19 Aug 2020 10:12:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727913AbgHSKMf (ORCPT ); Wed, 19 Aug 2020 06:12:35 -0400 Received: from mail.v3.sk ([167.172.186.51]:51730 "EHLO shell.v3.sk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727808AbgHSKMW (ORCPT ); Wed, 19 Aug 2020 06:12:22 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by zimbra.v3.sk (Postfix) with ESMTP id 3FFD6DFA71; Wed, 19 Aug 2020 10:11:24 +0000 (UTC) Received: from shell.v3.sk ([127.0.0.1]) by localhost (zimbra.v3.sk [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id 3Ym15nfYp3ad; Wed, 19 Aug 2020 10:11:23 +0000 (UTC) Received: from localhost (localhost.localdomain [127.0.0.1]) by zimbra.v3.sk (Postfix) with ESMTP id E05D0DFA44; Wed, 19 Aug 2020 10:11:22 +0000 (UTC) X-Virus-Scanned: amavisd-new at zimbra.v3.sk Received: from shell.v3.sk ([127.0.0.1]) by localhost (zimbra.v3.sk [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id AD0s2r5Zerf0; Wed, 19 Aug 2020 10:11:22 +0000 (UTC) Received: from localhost (unknown [109.183.109.54]) by zimbra.v3.sk (Postfix) with ESMTPSA id 81696DEE69; Wed, 19 Aug 2020 10:11:22 +0000 (UTC) From: Lubomir Rintel To: Thierry Reding Cc: Sam Ravnborg , David Airlie , Daniel Vetter , Rob Herring , dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 0/2] drm/panel: Add support for Innolux LS075AT011 Date: Wed, 19 Aug 2020 12:12:04 +0200 Message-Id: <20200819101206.633253-1-lkundrak@v3.sk> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Please take a look at the patches chanied to this message and consider applying them. They add description of the display panel found on OLPC laptops to the simple panel driver. There is no datasheet for the hardware and thus the timings were determined on a best effort basis. The clock range is gotten from the data sheet of the display controller [1] and the other timings are what OLPC laptops actually use. The panel seems to cope with different sync timings, but I'm not sure wherher there's any value in attempting to figure out what range is actually permissible. I could not figure out the right definitions for the connector and the bus format. I'm not sure how necessary they are, but at least the drm-panel driver insists on connector type being defined so I picked LVDS because that seems to be used for internal laptop screens. The signalling is not actually differential. It uses TTL levels with data sampled on rising and falling clock edges; sort of like this (taken from [1], P.20): __ FSTH / \_______________________________________ ____ ____ ____ ____ __ FCLK / \____/ \____/ \____/ \____/ ____ ____ ____ ____ ____ ____ ____ FD00 ........X____X____X____X____X____X____X____ ____ ____ ____ ____ ____ ____ ____ FD01 ........X____X____X____X____X____X____X____ ____ ____ ____ ____ ____ ____ ____ FD10 ........X____X____X____X____X____X____X____ ____ ____ ____ ____ ____ ____ ____ FD11 ........X____X____X____X____X____X____X____ ____ ____ ____ ____ ____ ____ ____ FD20 ........X____X____X____X____X____X____X____ ____ ____ ____ ____ ____ ____ ____ FD21 ........X____X____X____X____X____X____X____ | | | | data 1 data 2 ... (2x6bit) (2x6bit) I believe the data just carries brightness because each pixel on the panel has a fixed color; with the red, green and blue pixels organized in a pattern [2]. (The HX8837 that drives the color does the conversion from RGB). Tested on an OLPC XO-1.75 laptop. XO-1 and XO-1.5 use the same hardware, but their display controllers are not supported by DRM at the moment. [1] http://wiki.laptop.org/images/0/09/DCON_datasheet_HX8837-A.pdf [2] http://wiki.laptop.org/go/Display Thank you! Lubo