From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout-p-102.mailbox.org (mout-p-102.mailbox.org [80.241.56.152]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 600B1374196; Tue, 13 Jan 2026 08:04:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=80.241.56.152 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768291478; cv=none; b=YCY5U5Y+GvIJSQhR3Vpd4K4RKYlwssZzSZ4OGRi/VCtvA59JYSl/6T22mOAcvz7BsrTkDdicjlLYMRRtbarfh1EW3AtY06DBKN9Bp4bke4XKhwsgHgJbotXhDoU+b1AfZ2+LwJEOIZR5qLA9xKz2QyWjNhOVxE0dasDgGnbJHpQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768291478; c=relaxed/simple; bh=GjwYrgYrfMZ4SvDh0mCFrmc9NLm4jQkn+5aDxC0HviA=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=db5+wVTeVcMWtHJKVVyPm4TdSNujjOjm6yeULRBf1kb8d3hq8r+6rOUzno+w7FOIBjsNQtKx9Ef4o5KudulKz5WgjHhj4mM15Wy9AMjgf+bA1FwR3BlRuhou4SsPzkTfcnI8pChRviuU9tBQAgvBmsidwMr14bgS//YvInUSVgU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=mailbox.org; spf=pass smtp.mailfrom=mailbox.org; dkim=pass (2048-bit key) header.d=mailbox.org header.i=@mailbox.org header.b=DBF3yMEq; arc=none smtp.client-ip=80.241.56.152 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=mailbox.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mailbox.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=mailbox.org header.i=@mailbox.org header.b="DBF3yMEq" Received: from smtp102.mailbox.org (smtp102.mailbox.org [10.196.197.102]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-102.mailbox.org (Postfix) with ESMTPS id 4dr1x547kYz9tgD; Tue, 13 Jan 2026 09:04:25 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mailbox.org; s=mail20150812; t=1768291465; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=GkIauvv0RSplXY/m2pwszJK6bmYJH/Xs+FM5mAF4Bo0=; b=DBF3yMEq4YspPN6urHOQmHeSj0DvBnNq3ZFqsK7kz6uawWnUr8kLqU5WP1Ibr9D7xHLIrz N2yXhqBrc+LjzSfzfNZnoAi6YhF18GJNpAvW434/3HOatO0f5iIY2u0FZ27DQsj8w7g7nF igvXSl0pOdFWJ0sN43QBUTSWHPAa/mlRugoxp8/YNelN7fsNkIAnlFRXSAxi7tzAjh7sSR w2CZmTWUApIMLoTQehHtwQUl6GHiFhjKtRkfgc7Z0CM3ta3bTUI/4BG877Pi8U+iG1hN0z 0tJ4PPrfs+mKP8/nSclPeKxqSS535NYabfqb2CKdcTohN/eGOoNKjoSJLZQQnQ== Message-ID: <65ccfeb6-4962-4964-be1d-cfb0ed41773e@mailbox.org> Date: Tue, 13 Jan 2026 09:04:17 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [EXT] [PATCH 2/2] drm/bridge: waveshare-dsi: Add support for 1..4 DSI data lanes To: Joseph Guo , dri-devel@lists.freedesktop.org Cc: Andrzej Hajda , Conor Dooley , David Airlie , Jernej Skrabec , Jonas Karlman , Krzysztof Kozlowski , Laurent Pinchart , Maarten Lankhorst , Maxime Ripard , Neil Armstrong , Rob Herring , Robert Foss , Simona Vetter , Thomas Zimmermann , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-renesas-soc@vger.kernel.org References: <20260112234834.226128-1-marek.vasut+renesas@mailbox.org> <20260112234834.226128-2-marek.vasut+renesas@mailbox.org> <773b6e43-4f86-4b11-8e6b-a9f2561a75de@nxp.com> Content-Language: en-US From: Marek Vasut In-Reply-To: <773b6e43-4f86-4b11-8e6b-a9f2561a75de@nxp.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-MBO-RS-ID: fa438034bf0a4b1c6ad X-MBO-RS-META: gkcgcibyibgwe769u53joe6mewjg9ju6 On 1/13/26 7:41 AM, Joseph Guo wrote: > On 1/13/2026 7:47 AM, Marek Vasut wrote: >> [You don't often get email from marek.vasut+renesas@mailbox.org. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ] >> >> Caution: This is an external email. Please take care when clicking links or opening attachments. When in doubt, report the message using the 'Report this email' button >> >> >> Parse the data lane count out of DT. Limit the supported data lanes >> to 1..4 which is the maximum available DSI pairs on the connector of >> any known panels which may use this bridge. Internally, this bridge >> is an ChipOne ICN6211 which loads its register configuration from a >> dedicated storage and its I2C does not seem to be accessible. The >> ICN6211 also supports up to 4 DSI lanes, so this is a hard limit. >> >> To avoid any breakage on old DTs where the parsing of data lanes from >> DT may fail, fall back to the original hard-coded value of 2 lanes and >> warn user. >> >> The lane configuration is preconfigured in the bridge for each of the >> WaveShare panels. The 13.3" DSI panel works with 4-lane configuration, >> others seem to use 2-lane configuration. This is a hardware property, >> so the actual count should come from DT. >> >> > Hi Marek, > > I don't have 4 lanes waveshare panel on my hands. Have you tested with the 4-lane panel already? Yes, the 13.3" DSI panel is 4-lane https://www.waveshare.com/13.3inch-dsi-lcd.htm , I have it connected to Retronix Sparrow Hawk board which has 4-lane port. See also this patch I submitted, that is the DT binding for it: [PATCH 2/2] arm64: dts: renesas: sparrow-hawk: Add overlay for WaveShare Display 13.3"