From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from madrid.collaboradmins.com (madrid.collaboradmins.com [46.235.227.194]) (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 04C8B13AD22 for ; Wed, 17 Apr 2024 13:52:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=46.235.227.194 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713361945; cv=none; b=sjmPavy2Bpg6bw2sJ9XYecmD13NFPX/0uSdIw06DcOd643MJUVodtVerzPrnCRbigdeoyNV9veVF8KBhSQN2H0e4F1ehlZGvGQyMZnw80Hk5Em70vDzwHZz+cRJ2rM1iNU/58fbmqfkUGu5omrQs3Llz1lCo7W6jYYELX/nlX00= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713361945; c=relaxed/simple; bh=VxunfktQMOjppOCQpES9K8zlG6woQD+gav0HVLUYdWw=; h=Message-ID:Date:MIME-Version:Subject:To:References:From: In-Reply-To:Content-Type; b=QzRr1mOSwGAseqNlI1327cDrVhPiNHph6UUyk5CkquYFuuKZiJxXYytVfFwbICmRqawEBJhH8qUHdt8ztY9Z5i43XNh1ZG8J9yOvPt+Zns8qnrMEzmRF4Uo0aHCe868/kJZBxv8QiNuZ3VD6B0GHnGLyLEPFWVTWyyNilY31EZ8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b=Mykj5nAq; arc=none smtp.client-ip=46.235.227.194 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="Mykj5nAq" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1713361942; bh=VxunfktQMOjppOCQpES9K8zlG6woQD+gav0HVLUYdWw=; h=Date:Subject:To:References:From:In-Reply-To:From; b=Mykj5nAq4uZmDGUy8aeGxuqe1I9F/q86kU0nNQ1xVNXcg8XVae31Bm2y0lTzMLRxz sCbBts3Q1SnTtyf+WFufvN7v6WNYpJwBUoN1k7kZTBFXzQr3V5p5NWX3Od/aVo/z13 dcyJZqtU2prWJkdPjLYZkRNp7EoJzGjc7SHTX5MKlH0rQh2+K9hh1JGB/+PJkfi8iK 58QYY/y1ZXU2KXl29NUD5sHJrhTDD3on7edMTS7rVk+37dU6erHEzcqvjviarUFc6h M0BkSzY5TVdDI0g1canrfGMTmTSWsLkVVnnRDYmVwIiYpaCBC2x2gaSqy9+8cL/6e8 jsIu2PVVQMrHQ== Received: from [100.113.186.2] (cola.collaboradmins.com [195.201.22.229]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: kholk11) by madrid.collaboradmins.com (Postfix) with ESMTPSA id 7EB49378001E; Wed, 17 Apr 2024 13:52:21 +0000 (UTC) Message-ID: <275e760d-e4e2-4a6b-88f7-9a8590b0773b@collabora.com> Date: Wed, 17 Apr 2024 15:52:20 +0200 Precedence: bulk X-Mailing-List: chrome-platform@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] drm/mediatek/dp: fix mtk_dp_aux_transfer return value To: Wojciech Macek , Chun-Kuang Hu , Philipp Zabel , David Airlie , Daniel Vetter , Matthias Brugger , dri-devel@lists.freedesktop.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, chrome-platform@lists.linux.dev References: <20240417103819.990512-1-wmacek@chromium.org> From: AngeloGioacchino Del Regno Content-Language: en-US In-Reply-To: <20240417103819.990512-1-wmacek@chromium.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Il 17/04/24 12:38, Wojciech Macek ha scritto: > In case there is no DP device attached to the port the > transfer function should return IO error, similar to what > other drivers do. > In case EAGAIN is returned then any read from /dev/drm_dp_aux > device ends up in an infinite loop as the upper layers > constantly repeats the transfer request. > > Fixes: f70ac097a2cf ("drm/mediatek: Add MT8195 Embedded DisplayPort driver") > Signed-off-by: Wojciech Macek Reviewed-by: AngeloGioacchino Del Regno