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 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 85F6EC021B8 for ; Tue, 4 Mar 2025 15:23:24 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 08F9B10E618; Tue, 4 Mar 2025 15:23:24 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="J4Q2BzRv"; dkim-atps=neutral Received: from nyc.source.kernel.org (nyc.source.kernel.org [147.75.193.91]) by gabe.freedesktop.org (Postfix) with ESMTPS id D798410E618 for ; Tue, 4 Mar 2025 15:23:22 +0000 (UTC) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id 43414A457BC; Tue, 4 Mar 2025 15:17:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8B5D0C4CEE5; Tue, 4 Mar 2025 15:23:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1741101801; bh=wOZdyUaRyNj68ihWIOygiOcGTvvKLhUnXJHLbU9loN0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=J4Q2BzRvoV3D63ntQX7PJjECA5gNDcY3O5MJdc82JtYjlkGjJPffZEmxWvJXkINQr DICUn/02zKB0e2v7InznL8QpLBcNsAEvZapenQfRa1qCnOHw63v0lmbHAruGfblgwt DMFZWZDmWAOsdC+beiNN2Nwvz05DyuZGhzXTSGybPMwKYeVmlD+XlAx06Fia64QOQB CH5/+2lSpMOQim1fFY9YhZeSAHU9oQKu7N7zZpwHLHtm0s8+G/2BX3swytK6SyrH6K pgBsG1zG1xiz2Rv91U41AeVXb00uaSZPNY8rv6FACOh6hJXrQBL23oJLMWo8DF3voe pjQNcqG92VQiw== Date: Tue, 4 Mar 2025 09:23:20 -0600 From: Rob Herring To: Liu Ying Cc: dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, andrzej.hajda@intel.com, neil.armstrong@linaro.org, rfoss@kernel.org, Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@gmail.com, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, airlied@gmail.com, simona@ffwll.ch Subject: Re: [PATCH 3/5] dt-bindings: display: simple-bridge: Document DPI color encoder Message-ID: <20250304152320.GA2630063-robh@kernel.org> References: <20250304101530.969920-1-victor.liu@nxp.com> <20250304101530.969920-4-victor.liu@nxp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250304101530.969920-4-victor.liu@nxp.com> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Tue, Mar 04, 2025 at 06:15:28PM +0800, Liu Ying wrote: > A DPI color encoder, as a simple display bridge, converts input DPI color > coding to output DPI color coding, like Adafruit Kippah DPI hat[1] which > converts input 18-bit pixel data to 24-bit pixel data(with 2 low padding > bits in every color component though). Document the DPI color encoder. Why do we need a node for this? Isn't this just wired how it is wired and there's nothing for s/w to see or do? I suppose if you are trying to resolve the mode with 24-bit on one end and 18-bit on the other end, you need to allow that and not require an exact match. You still might need to figure out which pins the 18-bit data comes out on, but you have that problem with an 18-bit panel too. IOW, how is this any different if you have an 18-bit panel versus 24-bit panel? Rob