From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpout-02.galae.net (smtpout-02.galae.net [185.246.84.56]) (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 25D7832143B for ; Thu, 11 Sep 2025 12:50:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.246.84.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757595039; cv=none; b=S7K5/Ir6rvEZ4Crudk3h5jV8nkVD8WEhWwjrTz9Wp3Ebt57ukOZxHic/JKFtsE15j+Ao1uYLxuIZHo20kayuilRsX8fl8j62S6r9xxT7QZKL5RNjnAybO/N5v8SBZSYYvVWvQfOO8ZaQ4pb8MVwwLSOSGGKbCsY4E/jYFfXVuB8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757595039; c=relaxed/simple; bh=lic2gVyra2Fci9kjsobQWbVL/mughWwS6st0tFnXd3M=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=b4XvaGQomLQXNdMGjsrt0zBWCxFsRDrXnt4heyKSXWtq7b8qf4hHS0/QM2Yk8YjPcTyEiAi78d4pizsT6CnArIytA75opf3+CNFXFCYnSaTPZfODYo30MCmG6UgIjag7SZbDgpdh9d22pqacYZanSCPblAIqBaPcn8+GhN6hOcA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=0cSGvd0V; arc=none smtp.client-ip=185.246.84.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="0cSGvd0V" Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-02.galae.net (Postfix) with ESMTPS id 86DE81A0DEA; Thu, 11 Sep 2025 12:50:29 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 5A76D60630; Thu, 11 Sep 2025 12:50:29 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id B85C9102F286D; Thu, 11 Sep 2025 14:50:02 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1757595027; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:content-language:in-reply-to:references; bh=SLEM14Bc3F7M85qjcLqahAIN620oKBeJlXHCNZSNKo0=; b=0cSGvd0V3ky4ridmXNRbRRun5K9w3uXdqT/pIvja9hkdUrZqFZ0xBo97NoHhjP8hPlNk5g 5uDRFx0/WdkAFxDaIn7rLFDoWp4yBiHTPzVx4F2wiXFGu3RMWH/kZrFzHugLw9vNTYU0oY JTsdbiZ8mHtVZis7nGrWam29AgowuPiJfkn/OOWvmrDbD2BxCHf51m2n/NvPHR91vWor69 9FP9Yjc5p49ye7jRTaVzJNwcHBFE6ObsU754jL6vfKLKsuqiLQ/bwNqtf6hJr/J8RjGnhz 3+D/ov48BGWxZeUez/ywx9EFeOOZHcfiEeRd+3Ph1fXpsMhFE5xCmZf/sHU0Mw== Message-ID: <012046ab-d866-4b3a-8c8a-e130bc2b9628@bootlin.com> Date: Thu, 11 Sep 2025 14:49:59 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] drm/bridge: ite-it66121: Add drm_connector support To: Maxime Ripard Cc: Dmitry Baryshkov , Phong LE , Neil Armstrong , Andrzej Hajda , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Thomas Zimmermann , David Airlie , Simona Vetter , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, thomas.petazzoni@bootlin.com, miquel.raynal@bootlin.com, kory.maincent@bootlin.com, romain.gantois@bootlin.com, praneeth@ti.com, Aradhya Bhatia References: <20250909-it66121-fix-v1-1-bc79ca83df17@bootlin.com> <6164422a-6265-4726-8da5-68bb8eafb9e6@bootlin.com> <20250911-innocent-daffodil-macaque-797f13@houat> Content-Language: en-US From: Miguel Gazquez In-Reply-To: <20250911-innocent-daffodil-macaque-797f13@houat> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Last-TLS-Session-Version: TLSv1.3 Le 11/09/2025 à 11:50, Maxime Ripard a écrit : > On Thu, Sep 11, 2025 at 10:51:06AM +0200, Miguel Gazquez wrote: >> >> >> Le 10/09/2025 à 04:28, Dmitry Baryshkov a écrit : >>> On Tue, Sep 09, 2025 at 06:16:43PM +0200, Miguel Gazquez wrote: >>>> From: Aradhya Bhatia >>>> >>>> Add support for DRM connector and make the driver support the older >>>> format of attaching connectors onto the encoder->bridge->connector >>>> chain. >>>> This makes the driver compatible with display controller that only >>>> supports the old format. >>>> >>>> [Miguel Gazquez: Rebased + made driver work with or without >>>> DRM_BRIDGE_ATTACH_NO_CONNECTOR] >>> >>> What is the use case for not using DRM_BRIDGE_ATTACH_NO_CONNECTOR? >> >> Some display controller drivers (like the tilcdc) call drm_bridge_attach >> without DRM_BRIDGE_ATTACH_NO_CONNECTOR, so the bridge must support both with >> and without DRM_BRIDGE_ATTACH_NO_CONNECTOR to be compatible with all display >> controllers. > > I'd rather convert tilcdc to use DRM_BRIDGE_ATTACH_NO_CONNECTOR then. The problem is that doing that break devicetrees using the tilcdc and a bridge who doesn't support DRM_BRIDGE_ATTACH_NO_CONNECTOR (there are multiple bridges that don't support DRM_BRIDGE_ATTACH_NO_CONNECTOR), and if my understanding is correct breaking devicetrees is not allowed. > > Maxime -- Miguel Gazquez, Bootlin Embedded Linux and Kernel engineering https://bootlin.com