From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.forwardemail.net (smtp.forwardemail.net [121.127.44.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4F98A287268 for ; Sun, 10 May 2026 12:42:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=121.127.44.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778416931; cv=none; b=h5YCrXGQ2UXu62SpQacbEhEPE5zOjvciTRrAlsE34rte7VRYTOkm6TpABjYqvASDGgIyvgxyfJXv0AJLxM+Y7SZs9LOd6hTY2HwcFjWxKLTePJBJFiOrs6ebImAkli5oeATBlG6W7V8rygORNoY3tZP0KpOfSQ64D2ZMWlljO5s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778416931; c=relaxed/simple; bh=icexU5CMtRCStl6NNkvlkrzztdsTVgYec9+/gXOnQxs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SK45lcxeF0Sp2AJiUi2/Jrsix/j8JNeUxmxYtds79+5ZMOX/xeIocOkBjmulAletIOrHJn129ODgXmc8TtnCTRvL3iiZKmNYq0ANixmLyP+haDML/i5dN+vlVYLAWOHMKWkh7tQQegXSzPBeHe1OQ/aks1yZu4s6hDqSm3XbYPE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=kwiboo.se; spf=pass smtp.mailfrom=fe-bounces.kwiboo.se; dkim=pass (2048-bit key) header.d=kwiboo.se header.i=@kwiboo.se header.b=YhlkrLZR; arc=none smtp.client-ip=121.127.44.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=kwiboo.se Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=fe-bounces.kwiboo.se Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kwiboo.se header.i=@kwiboo.se header.b="YhlkrLZR" 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=1778416916; bh=YPElDtV9eg2ObFwq32yfRisczcjIwpWrEjsNQBlqzi0=; b=YhlkrLZRWwq2XbbsDUaX02ZVag0jmccag3rZh+RSlfDnBQDkTZyXmZH8pRNV6l9JWPXF+7ah+ Vgzr+nHsz3guIBk5A6qUSqpnA6/WtI+oUvEGY8Usj1tnH169506G6AXTLyvJbIGu2wEXuxBJtuJ yebUcXI8neZBhETIL9wa8rK180nvQ4PanpJTh/wCP1l3ZP+M80IA+16GQIL1iLmFH7gvgJOXCGB a2tEN/AIiK6B3KtnpafCdvi3bW18bcbsJ7oaNDTcUBI+16ifKk8n/iPif344k89aVaMkZKsMn3Z l6MPaR2IWeM73XdFv9phtcSpCdyxtDVqtsRsD1bVKMzQ== X-Forward-Email-ID: 6a007cf30d91f03a31a0bb02 X-Forward-Email-Sender: rfc822; jonas@kwiboo.se, smtp.forwardemail.net, 121.127.44.73 X-Forward-Email-Version: 2.8.0 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 , Luca Ceresoli , 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 v5 01/21] drm: bridge: dw_hdmi: Disable scrambler feature when not supported Date: Sun, 10 May 2026 12:40:45 +0000 Message-ID: <20260510124111.1226584-2-jonas@kwiboo.se> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260510124111.1226584-1-jonas@kwiboo.se> References: <20260510124111.1226584-1-jonas@kwiboo.se> Precedence: bulk X-Mailing-List: imx@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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 --- v5: No change 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 41b3a9cfa2f5..d3e6a6562870 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