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=-3.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 EFCFBC433E7 for ; Sat, 10 Oct 2020 00:04:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ADB8A2222F for ; Sat, 10 Oct 2020 00:04:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="AsJihnaG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728431AbgJJACO (ORCPT ); Fri, 9 Oct 2020 20:02:14 -0400 Received: from perceval.ideasonboard.com ([213.167.242.64]:38118 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728557AbgJIX7h (ORCPT ); Fri, 9 Oct 2020 19:59:37 -0400 Received: from pendragon.ideasonboard.com (62-78-145-57.bb.dnainternet.fi [62.78.145.57]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 7BB2E528; Sat, 10 Oct 2020 01:59:27 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1602287967; bh=hQoSfHq4w68Q8YI1olTrIlcr8qpEmfR2zY8Trc10LPQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=AsJihnaGYD4EMaCzVQqF4DINZ64tw+G+q3wq70IU/ZmJ1uUpGVFszJS7uphcJQMqa wV1hAmWrF4dNnbBgkNgeKkARaIoBsI4oUlvDWlrbDnL0YMZs8XldaGim+Ekm/reGxs /Ai5vx69tPuw2kfzG25e6Ufgw6rY6V5OVAf+a5vk= Date: Sat, 10 Oct 2020 02:58:43 +0300 From: Laurent Pinchart To: Marek Vasut Cc: dri-devel@lists.freedesktop.org, Stefan Agner , devicetree@vger.kernel.org, Guido =?utf-8?Q?G=C3=BCnther?= , Rob Herring , Pengutronix Kernel Team , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2 3/7] dt-bindings: display: mxsfb: Add a bus-width endpoint property Message-ID: <20201009235843.GR25040@pendragon.ideasonboard.com> References: <20201007012438.27970-1-laurent.pinchart@ideasonboard.com> <20201007012438.27970-4-laurent.pinchart@ideasonboard.com> <7b8df7af-5ca8-708b-4975-2fdf4280116f@denx.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <7b8df7af-5ca8-708b-4975-2fdf4280116f@denx.de> Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi Marek, On Wed, Oct 07, 2020 at 10:40:26AM +0200, Marek Vasut wrote: > On 10/7/20 3:24 AM, Laurent Pinchart wrote: > > [...] > > > + bus-width: > > + enum: [16, 18, 24] > > + description: | > > + The output bus width. This value overrides the configuration > > + derived from the connected device (encoder or panel). It should > > + only be specified when PCB routing of the data signals require a > > + different bus width on the LCDIF and the connected device. For > > + instance, when a 18-bit RGB panel has its R[5:0], G[5:0] and > > + B[5:0] signals connected to LCD_DATA[7:2], LCD_DATA[15:10] and > > + LCD_DATA[23:18] instead of LCD_DATA[5:0], LCD_DATA[11:6] and > > + LCD_DATA[17:12], bus-width should be set to 24. > > The iMX6 IPUv3 uses interface-pix-fmt which is a bit more flexible, but > I'm not sure whether it's the right way to go about this, see: > Documentation/devicetree/bindings/display/imx/fsl-imx-drm.txt I think specifying the bus with is better. It's a standard property, but more than that, a given bus width can carry different formats. For instance, a 24-bus could carry RGB666 data (with dithering for the LSBs). -- Regards, Laurent Pinchart