[PATCH v6 1/4] drm/mediatek: disable tmds on mt2701

Frank Wunderlich linux at fw-web.de
Fri Sep 4 06:59:59 EDT 2020


From: chunhui dai <chunhui.dai at mediatek.com>

Without that patch if you use specific resolutions like 1280x1024,
I can see distortion in the output. It seems as if the
frequency for updating the pixel of the image is out of sync.

For initialization tmds needs to be active, but can be disabled after init
to fix blurry display

Signed-off-by: chunhui dai <chunhui.dai at mediatek.com>
Signed-off-by: Frank Wunderlich <frank-w at public-files.de>
Tested-by: Frank Wunderlich <frank-w at public-files.de>
---
 drivers/phy/mediatek/phy-mtk-hdmi-mt2701.c | 1 +
 drivers/phy/mediatek/phy-mtk-hdmi.c        | 3 +++
 drivers/phy/mediatek/phy-mtk-hdmi.h        | 1 +
 3 files changed, 5 insertions(+)

diff --git a/drivers/phy/mediatek/phy-mtk-hdmi-mt2701.c b/drivers/phy/mediatek/phy-mtk-hdmi-mt2701.c
index a6cb1dea3d0c..b74c65a1762c 100644
--- a/drivers/phy/mediatek/phy-mtk-hdmi-mt2701.c
+++ b/drivers/phy/mediatek/phy-mtk-hdmi-mt2701.c
@@ -238,6 +238,7 @@ static void mtk_hdmi_phy_disable_tmds(struct mtk_hdmi_phy *hdmi_phy)
 
 struct mtk_hdmi_phy_conf mtk_hdmi_phy_2701_conf = {
 	.flags = CLK_SET_RATE_GATE,
+	.pll_default_off = true,
 	.hdmi_phy_clk_ops = &mtk_hdmi_phy_pll_ops,
 	.hdmi_phy_enable_tmds = mtk_hdmi_phy_enable_tmds,
 	.hdmi_phy_disable_tmds = mtk_hdmi_phy_disable_tmds,
diff --git a/drivers/phy/mediatek/phy-mtk-hdmi.c b/drivers/phy/mediatek/phy-mtk-hdmi.c
index 8fc83f01a720..47c029d4b270 100644
--- a/drivers/phy/mediatek/phy-mtk-hdmi.c
+++ b/drivers/phy/mediatek/phy-mtk-hdmi.c
@@ -184,6 +184,9 @@ static int mtk_hdmi_phy_probe(struct platform_device *pdev)
 		return PTR_ERR(phy_provider);
 	}
 
+	if (hdmi_phy->conf->pll_default_off)
+		hdmi_phy->conf->hdmi_phy_disable_tmds(hdmi_phy);
+
 	return of_clk_add_provider(dev->of_node, of_clk_src_simple_get,
 				   hdmi_phy->pll);
 }
diff --git a/drivers/phy/mediatek/phy-mtk-hdmi.h b/drivers/phy/mediatek/phy-mtk-hdmi.h
index b13e1d5f8e78..dcf9bb13699b 100644
--- a/drivers/phy/mediatek/phy-mtk-hdmi.h
+++ b/drivers/phy/mediatek/phy-mtk-hdmi.h
@@ -21,6 +21,7 @@ struct mtk_hdmi_phy;
 
 struct mtk_hdmi_phy_conf {
 	unsigned long flags;
+	bool pll_default_off;
 	const struct clk_ops *hdmi_phy_clk_ops;
 	void (*hdmi_phy_enable_tmds)(struct mtk_hdmi_phy *hdmi_phy);
 	void (*hdmi_phy_disable_tmds)(struct mtk_hdmi_phy *hdmi_phy);
-- 
2.25.1




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