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From:   Bo-Chen Chen <rex-bc.chen@mediatek.com>
To:     <chunkuang.hu@kernel.org>, <p.zabel@pengutronix.de>,
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CC:     <msp@baylibre.com>, <granquet@baylibre.com>,
        <jitao.shi@mediatek.com>, <wenst@chromium.org>,
        <angelogioacchino.delregno@collabora.com>, <ck.hu@mediatek.com>,
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        <linux-mediatek@lists.infradead.org>, <devicetree@vger.kernel.org>,
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        <linux-fbdev@vger.kernel.org>,
        <Project_Global_Chrome_Upstream_Group@mediatek.com>,
        Bo-Chen Chen <rex-bc.chen@mediatek.com>
Subject: [PATCH v16 6/8] drm/mediatek: set monitor to DP_SET_POWER_D3 to avoid garbage
Date:   Fri, 5 Aug 2022 18:14:57 +0800
Message-ID: <20220805101459.3386-7-rex-bc.chen@mediatek.com>
In-Reply-To: <20220805101459.3386-1-rex-bc.chen@mediatek.com>
References: <20220805101459.3386-1-rex-bc.chen@mediatek.com>
MIME-Version: 1.0
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Set the monitor power state to DP_SET_POWER_D3 to avoid garbage.

Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
Signed-off-by: Bo-Chen Chen <rex-bc.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
---
 drivers/gpu/drm/mediatek/mtk_dp.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_dp.c b/drivers/gpu/drm/mediatek/mtk_dp.c
index 487f3ed0c19f..75a2a0645d3d 100644
--- a/drivers/gpu/drm/mediatek/mtk_dp.c
+++ b/drivers/gpu/drm/mediatek/mtk_dp.c
@@ -1782,6 +1782,11 @@ static void mtk_dp_bridge_atomic_disable(struct drm_bridge *bridge,
 {
 	struct mtk_dp *mtk_dp = mtk_dp_from_bridge(bridge);
 
+	if (mtk_dp_plug_state(mtk_dp)) {
+		drm_dp_dpcd_writeb(&mtk_dp->aux, DP_SET_POWER, DP_SET_POWER_D3);
+		usleep_range(2000, 3000);
+	}
+
 	mtk_dp_video_mute(mtk_dp, true);
 
 	mtk_dp->enabled = false;
-- 
2.18.0