From patchwork Wed Dec 18 11:34:07 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liankun Yang X-Patchwork-Id: 13913523 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 91544E77188 for ; Wed, 18 Dec 2024 11:36:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Message-ID:Date:Subject:CC:To:From: Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender :Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=RWw0YjfIq3RA4Wmm35YTKkdNVZn5xNSpCYbBF0u+pzc=; b=KRo5V6E5Elc4FKyNiSdfhqQ3m1 YMQaQhfmUQtVI8JZYnLRmG6NXgu/Sb2NPnmVS3JKwdL4jxCgM8XRJWNWjkK41B+IVKNrazx7vNlZW iRhne7vKBdAltL432/lXiyDkLxc86J0rWaxkITxLR8OkdVhMik4FtUoA+H4Dktv42LaPT2LpSQ0KY H6EzyUPq9jRPAiD1htDjXZXzFDo+lxNP5kQNFT0AF1NGZg8xP7Msn0Owhioiq3lfubvs5wExwRkoK ezEvx26NfAN/cnu8XQ4dWZKm4iPnumi+3NWHSTwCdIl3/Gj0b15woQEDOUWyXnKVEXoGH51vgW8az KZnvdRKg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tNsLb-0000000GT5F-2hIX; Wed, 18 Dec 2024 11:36:11 +0000 Received: from mailgw01.mediatek.com ([216.200.240.184]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tNsKU-0000000GSqI-3kaH; Wed, 18 Dec 2024 11:35:04 +0000 X-UUID: 1a265c44bd3411ef82ff63e91e7eb18c-20241218 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=RWw0YjfIq3RA4Wmm35YTKkdNVZn5xNSpCYbBF0u+pzc=; b=ZaO1ix1zrIuHHCVWE1+zLy7E70trKYEUiug88KBu+2g6z7ke4LQMXkcvCdwDZORPrFtaguROzugt6zWHISLhhRpd0AFAXbhUwNui2DAf4lwZ0IpYQS+CWaKGD3PEd/D7ofOb8iR2IyhyKClZ6QhLPXs5cZ8acV1nD48S5NJRecw=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.45,REQID:922ec55e-32bd-4ecb-9f86-e5124138de9d,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:6493067,CLOUDID:448e5513-8f5d-4ac6-9276-7b9691c7b8d6,B ulkID:nil,BulkQuantity:0,Recheck:0,SF:102,TC:nil,Content:0,EDM:-3,IP:nil,U RL: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_SNR,TF_CID_SPAM_ULS X-UUID: 1a265c44bd3411ef82ff63e91e7eb18c-20241218 Received: from mtkmbs09n2.mediatek.inc [(172.21.101.94)] by mailgw01.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 1980500206; Wed, 18 Dec 2024 04:34:54 -0700 Received: from mtkmbs11n2.mediatek.inc (172.21.101.187) by mtkmbs11n2.mediatek.inc (172.21.101.187) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.26; Wed, 18 Dec 2024 19:34:51 +0800 Received: from mszsdclx1211.gcn.mediatek.inc (10.16.7.31) by mtkmbs11n2.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.1118.26 via Frontend Transport; Wed, 18 Dec 2024 19:34:51 +0800 From: Liankun Yang To: , , , , , , , , , , , , , , CC: , , , Subject: [PATCH v3 1/1] drm/mediatek: Add return value check when reading DPCD Date: Wed, 18 Dec 2024 19:34:07 +0800 Message-ID: <20241218113448.2992-1-liankun.yang@mediatek.com> X-Mailer: git-send-email 2.45.2 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241218_033502_930744_C4AB6E6D X-CRM114-Status: GOOD ( 13.32 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org 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 Reviewed-by: Guillaume Ranquet --- 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..b26dad8783be 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)) ret = connector_status_connected; if (!enabled)