From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 F2D1619753E; Thu, 6 Jun 2024 14:09:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717682982; cv=none; b=Xp0SrnVM552jhn5ILA0jONd7GbxvBwJ4WdYCeYdmu2y0hFMAIzx150NpTjSlL1uKhASbQD7uudb6bSohDXB01UqJZfeJWpFXHwa+PRxkQfVmQFOpUop94FP3aRRhk5cvQS2E9VrO6e3xxmwKNKbzEDVarBKb5dwRse/IcB+yGvw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717682982; c=relaxed/simple; bh=CffEr3wslm1qOz3Pbl5gop9UTVXexnvknkF3MqDhDfk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=hTbCePZ2MVzBK2+CB3OJVqKBNq6wAXNgMZZTav52QuOw4fMXGBAuI9+DKk2rZVYHngWZprL3wDDXb9RvuC5V+r1uBGboxdXn+7AMWbrqXEhlvF3veWVFfzb3Gl175MWslL7o0D1WS16GurCFu5E40zySno7EOHTzDFer6NpqOGs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=S3g/fmH4; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="S3g/fmH4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D31E3C32781; Thu, 6 Jun 2024 14:09:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1717682981; bh=CffEr3wslm1qOz3Pbl5gop9UTVXexnvknkF3MqDhDfk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=S3g/fmH4/gVIp7kHRnMeGlN3wKQhBLVP/CVOA/X5EFr2YND82RNHOSzWKv2Hs/67r F0idZ4aiWyOSIu1m/HwJg87do3h/cYqETvrRtcCNrT6DrWVIdmNQfkIy8QccsuMb0I QWrTOlsqPNUtgBzMswk8KrOnWgfsmJQzWDOG1B7E= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Wojciech Macek , AngeloGioacchino Del Regno , CK Hu , Chun-Kuang Hu , Sasha Levin Subject: [PATCH 6.9 165/374] drm/mediatek: dp: Fix mtk_dp_aux_transfer return value Date: Thu, 6 Jun 2024 16:02:24 +0200 Message-ID: <20240606131657.434161761@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240606131651.683718371@linuxfoundation.org> References: <20240606131651.683718371@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Wojciech Macek [ Upstream commit 8431fff9e0f3fc1c5844cf99a73b49b63ceed481 ] 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 Reviewed-by: CK Hu Link: https://patchwork.kernel.org/project/dri-devel/patch/20240417103819.990512-1-wmacek@chromium.org/ Signed-off-by: Chun-Kuang Hu Signed-off-by: Sasha Levin --- drivers/gpu/drm/mediatek/mtk_dp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c index 0ba72102636aa..536366956447a 100644 --- a/drivers/gpu/drm/mediatek/mtk_dp.c +++ b/drivers/gpu/drm/mediatek/mtk_dp.c @@ -2104,7 +2104,7 @@ static ssize_t mtk_dp_aux_transfer(struct drm_dp_aux *mtk_aux, if (mtk_dp->bridge.type != DRM_MODE_CONNECTOR_eDP && !mtk_dp->train_info.cable_plugged_in) { - ret = -EAGAIN; + ret = -EIO; goto err; } -- 2.43.0