From patchwork Fri Jan 3 07:33:22 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liankun Yang X-Patchwork-Id: 13925281 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 DDD2EE7718F for ; Fri, 3 Jan 2025 07:34:37 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 5456D10E190; Fri, 3 Jan 2025 07:34:37 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=mediatek.com header.i=@mediatek.com header.b="KP1iPlWq"; dkim-atps=neutral Received: from mailgw02.mediatek.com (unknown [210.61.82.184]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0195110E190 for ; Fri, 3 Jan 2025 07:34:34 +0000 (UTC) X-UUID: 2ab5a3e4c9a511efbd192953cf12861f-20250103 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Type:Content-Transfer-Encoding:MIME-Version:Message-ID:Date:Subject:CC:To:From; bh=cMDSCtGjZWJsWp0VLSuytv75YuoxhvMH+zr0NBthYg4=; b=KP1iPlWqnO5mgSAAyfLGAG8Xi3QjSIpMirvZuj4k4POPhoy3gstCpR/oYVeHq7XXKgDUEo2pSeHmRCuDRz6m4q2xE14dw/DIomQUPJOt0Puq/SQdhw2NcgnfmZRppQLvp8lpsi0zLBJtrwu0qo2VDUuXIvUAH+D/hlL4ZUPz1+E=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.46, REQID:6fce66d8-47c6-41e3-8e29-bdc1ee9dff96, IP:0, U RL:0,TC:0,Content:0,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION: release,TS:0 X-CID-META: VersionHash:60aa074, CLOUDID:236c4d37-e11c-4c1a-89f7-e7a032832c40, B ulkID:nil,BulkQuantity:0,Recheck:0,SF:102,TC:nil,Content:0|50,EDM:-3,IP:ni l,URL:1,File:nil,RT:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0,OSA:0,AV:0,LES :1,SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 0,NGT X-CID-BAS: 0,NGT,0,_ X-CID-FACTOR: TF_CID_SPAM_ULS,TF_CID_SPAM_SNR X-UUID: 2ab5a3e4c9a511efbd192953cf12861f-20250103 Received: from mtkmbs14n1.mediatek.inc [(172.21.101.75)] by mailgw02.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 2142198021; Fri, 03 Jan 2025 15:34:29 +0800 Received: from mtkmbs13n1.mediatek.inc (172.21.101.193) by MTKMBS14N1.mediatek.inc (172.21.101.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.26; Fri, 3 Jan 2025 15:34:28 +0800 Received: from mszsdhlt06.gcn.mediatek.inc (10.16.6.206) by mtkmbs13n1.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.1118.26 via Frontend Transport; Fri, 3 Jan 2025 15:34:27 +0800 From: Liankun Yang To: , , , , , , , , , , , , , , , CC: , , , Subject: [PATCH v4 1/1] drm/mediatek: Add return value check when reading DPCD Date: Fri, 3 Jan 2025 15:33:22 +0800 Message-ID: <20250103073425.28615-1-liankun.yang@mediatek.com> X-Mailer: git-send-email 2.45.2 MIME-Version: 1.0 X-MTK: N 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" Returns the number of bytes transferred (1) on success. Check the return value to confirm that AUX communication is successful. Fixes: f70ac097a2cf ("drm/mediatek: Add MT8195 Embedded DisplayPort driver") Signed-off-by: Liankun Yang --- Changes in V4: - Fix IF judgement condition. Per suggestion from the previous thread: https://patchwork.kernel.org/project/linux-mediatek/patch/20241218113448.2992-1-liankun.yang@mediatek.com/ Changes in V3: - Using drm_dp_read_sink_count() to improve patch. Per suggestion from the previous thread: https://patchwork.kernel.org/project/linux-mediatek/patch/20241128030940.25657-1-liankun.yang@mediatek.com/ Changes in V2: - Modify Fixes in Commit Message. Per suggestion from the previous thread: https://patchwork.kernel.org/project/linux-mediatek/patch/20240930092000.5385-1-liankun.yang@mediatek.com/ --- drivers/gpu/drm/mediatek/mtk_dp.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c index 36713c176cfc..b8e4e9a6eb78 100644 --- a/drivers/gpu/drm/mediatek/mtk_dp.c +++ b/drivers/gpu/drm/mediatek/mtk_dp.c @@ -2100,7 +2100,6 @@ static enum drm_connector_status mtk_dp_bdg_detect(struct drm_bridge *bridge) struct mtk_dp *mtk_dp = mtk_dp_from_bridge(bridge); enum drm_connector_status ret = connector_status_disconnected; bool enabled = mtk_dp->enabled; - u8 sink_count = 0; if (!mtk_dp->train_info.cable_plugged_in) return ret; @@ -2115,8 +2114,8 @@ static enum drm_connector_status mtk_dp_bdg_detect(struct drm_bridge *bridge) * function, we just need to check the HPD connection to check * whether we connect to a sink device. */ - drm_dp_dpcd_readb(&mtk_dp->aux, DP_SINK_COUNT, &sink_count); - if (DP_GET_SINK_COUNT(sink_count)) + + if (drm_dp_read_sink_count(&mtk_dp->aux) > 0) ret = connector_status_connected; if (!enabled)