From nobody Tue Apr 7 13:46:41 2026 Received: from smtp.forwardemail.net (smtp.forwardemail.net [121.127.44.66]) (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 4DC3B3CAE65 for ; Fri, 3 Apr 2026 18:53:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=121.127.44.66 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775242423; cv=none; b=RrwvMUlWPlCdSWk7Zm/kQ7r1s0eaZ+e1LcYRhB1UaSrrkZReuWMAmGyaceYQ2e4biQBe+wiWgaHp2y9xAJ4XzdbqWxdSTUoxvAZBXHWbbthjRsyYWSiDpHNJekoeN6JtJPizou4ayYu3k7fMZYS1AGIhX95xVX3LWSNtD0fBJHA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775242423; c=relaxed/simple; bh=ZH6f5fLbD2KjyjSMgLUm/g1DvyXJjnzgDgqIvEktCAE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SczH5hstKh8vAFllgMyVN32Y5qfvajn0nGnF7AIGtO611J0YCADPDZnB0SUBPE8VZpvIKQwHqP2ZZkf4j5yd5/SdCEeVO/Fm4dqiAhxgb0Zd7iuekvEsk9rWHZd9DqtZ2ZHry4pIOTqlLyr/oH//o/zo59BZvkFJ13bjWME4Nyg= 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=xZApzcAF; arc=none smtp.client-ip=121.127.44.66 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="xZApzcAF" 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=1775242414; bh=IrkmYXz+eQlVd/BohsNjaWpAwzykhtdCHiqXQ19+Tno=; b=xZApzcAF53F1tRje1dlRwqDoFq4mCyYYLD6a/STRl1hnqRokuBUjDC4ij1MjAbnOGvfZcx3qz r+1YAghFwzQBhDk+ZnlRhoC8v8kWZxhGe0QMBlyadgBNmcp29PE5ihubY12kEuX5qqELr6drZQJ WB05wpySIzuiW/v6B8XCKXkNvjoNHm8QOaRGqhxc2e/zoMiSe9dPLLTyTblF0mQr+YCYRy+WaHu VDmmwTRlRznWa0HwWm7bzwM4Vb7s+LQIeV8wjMPz40I24bS7lU2+tOOxolpl7I1BP071I2EbYqY xwvzSkMI1dwrbSJgy1lSrjRNW6zYTiVLfqJBRiZCLngg== X-Forward-Email-ID: 69d00cabdc98192b40b89309 X-Forward-Email-Sender: rfc822; jonas@kwiboo.se, smtp.forwardemail.net, 121.127.44.66 X-Forward-Email-Version: 2.6.68 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 , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter Cc: Christian Hewitt , Diederik de Haas , dri-devel@lists.freedesktop.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org, Christopher Obbard Subject: [PATCH v3 01/13] drm: bridge: dw_hdmi: Disable scrambler feature when not supported Date: Fri, 3 Apr 2026 18:52:47 +0000 Message-ID: <20260403185303.80748-2-jonas@kwiboo.se> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260403185303.80748-1-jonas@kwiboo.se> References: <20260403185303.80748-1-jonas@kwiboo.se> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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 sup= port") Reported-by: Christopher Obbard Reviewed-by: Neil Armstrong Signed-off-by: Jonas Karlman --- 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/br= idge/synopsys/dw-hdmi.c index 0296e110ce65..9febcb58a1df 100644 --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c @@ -2133,6 +2133,8 @@ static void hdmi_av_composer(struct dw_hdmi *hdmi, HDMI_MC_SWRSTZ); drm_scdc_set_scrambling(hdmi->curr_conn, 0); } + } else if (hdmi->version >=3D 0x200a) { + hdmi_writeb(hdmi, 0, HDMI_FC_SCRAMBLER_CTRL); } =20 /* Set up horizontal active pixel width */ --=20 2.53.0