From mboxrd@z Thu Jan 1 00:00:00 1970 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 8D91ACD342F for ; Mon, 4 May 2026 19:11:37 +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-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=NVWUpLoYoqwHrhK1PEs6caGhSJc5nSsIxxdrR4kmbpQ=; b=qxjwq1sPcD0u4l0S8tn25RANkI 4K6Cz3E52vDuabrPdzG8LT6rNPdrUOC/3CkLLTlcWIpn3uY7NugE+zCbGa2VTiYjlq649RtLVBTLw ty6YMzKYEgPX45WX8MSi920XvKE6wZbUOwWkcoMo4fbBSUj012dhcSm20HXVFUr7Z/InmuXglTsal 2KeAdf+Bi5KOu29YNZJCkfIE26yyD9p/+McrMinkSUiADLbPo3S3mw3TajNPibS5DQwyEeFPy7vNY EVZ1DsI+OsWzD7ag+F8b1AcymoNzsXc+Gb0OjRxLqu9cIMaa1zRQzHV3UluOZsHhvbYNe57Qiv8Hh CDONxmCA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wJyhY-0000000E4xT-160f; Mon, 04 May 2026 19:11:32 +0000 Received: from smtp.forwardemail.net ([149.28.215.223]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1wJyhT-0000000E4tH-0GIU for linux-arm-kernel@lists.infradead.org; Mon, 04 May 2026 19:11:30 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kwiboo.se; h=Content-Transfer-Encoding: MIME-Version: References: In-Reply-To: Message-ID: Date: Subject: Cc: To: From; q=dns/txt; s=fe-e1b5cab7be; t=1777921886; bh=NVWUpLoYoqwHrhK1PEs6caGhSJc5nSsIxxdrR4kmbpQ=; b=rKqvoAFzUm6XcmLFTLRbfxVkDbE/bzg6fm0XslDNsU2Du0KXOBh/PtpHFyfGVqrhb49MmIeKQ TKlX06U5JIbzB1z73UUIo8BREI35mPZgdVSldGmjodcMDNUU0Jd+QBrSrbstC7W/Isu+w3QlZwp CLpAwBrjDLoAqTCfTK7JSy8kyndKJ4Ux66herb+pyLKIFPN0NGQrQMdhemq58RQ76W13gTttocY OZwlvN+F8LgjA53YeJP9zYd946vQbz9e6LFEPR7gUNaAJluqCmOORHsebldA4wzfjBiDujDkV0z q+rdn0gd+487TyNMuEafK1ILgPg4olC73Xz+3QRY4y+g== X-Forward-Email-ID: 69f8ef4e04bb1dff846bb7fb X-Forward-Email-Sender: rfc822; jonas@kwiboo.se, smtp.forwardemail.net, 149.28.215.223 X-Forward-Email-Version: 2.7.7 X-Forward-Email-Website: https://forwardemail.net X-Complaints-To: abuse@forwardemail.net X-Report-Abuse: abuse@forwardemail.net X-Report-Abuse-To: abuse@forwardemail.net From: Jonas Karlman To: Andrzej Hajda , Neil Armstrong , Robert Foss , Heiko Stuebner , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter Cc: Liu Ying , Sandy Huang , Andy Yan , Chen-Yu Tsai , Christian Hewitt , Diederik de Haas , Nicolas Frattaroli , Dmitry Baryshkov , dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-amlogic@lists.infradead.org, linux-sunxi@lists.linux.dev, imx@lists.linux.dev, linux-kernel@vger.kernel.org, Christopher Obbard Subject: [PATCH v4 01/17] drm: bridge: dw_hdmi: Disable scrambler feature when not supported Date: Mon, 4 May 2026 19:10:38 +0000 Message-ID: <20260504191059.275928-2-jonas@kwiboo.se> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260504191059.275928-1-jonas@kwiboo.se> References: <20260504191059.275928-1-jonas@kwiboo.se> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260504_121127_411764_15E8612D X-CRM114-Status: GOOD ( 11.82 ) X-BeenThere: linux-arm-kernel@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-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The scrambler feature can be left enabled when hotplugging from a sink and mode that require scrambling to a sink that does not support SCDC or scrambling. Typically a blank screen or 'no signal' message can be observed after using a HDMI 2.0 4K@60Hz mode and then hotplugging to a sink that only support HDMI 1.4. Fix this by disabling the scrambler feature when SCDC is not supported. Fixes: 264fce6cc2c1 ("drm/bridge: dw-hdmi: Add SCDC and TMDS Scrambling support") Reported-by: Christopher Obbard Reviewed-by: Neil Armstrong Signed-off-by: Jonas Karlman --- v4: No change v3: Collect r-b tag v2: New patch --- drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c index f4a1ebb79716..248454c45d6b 100644 --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c @@ -2135,6 +2135,8 @@ static void hdmi_av_composer(struct dw_hdmi *hdmi, HDMI_MC_SWRSTZ); drm_scdc_set_scrambling(hdmi->curr_conn, 0); } + } else if (hdmi->version >= 0x200a) { + hdmi_writeb(hdmi, 0, HDMI_FC_SCRAMBLER_CTRL); } /* Set up horizontal active pixel width */ -- 2.54.0