[PATCH v4 3/3] drm/mediatek: fix the wrong pixel clock when resolution is 4K

Bibby Hsieh bibby.hsieh at mediatek.com
Tue Aug 16 23:58:08 PDT 2016


From: Junzhi Zhao <junzhi.zhao at mediatek.com>

Pixel clock should be 297MHz when resolution is 4K.

Signed-off-by: Junzhi Zhao <junzhi.zhao at mediatek.com>
Signed-off-by: Bibby Hsieh <bibby.hsieh at mediatek.com>
---
 drivers/gpu/drm/mediatek/mtk_dpi.c |    9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c b/drivers/gpu/drm/mediatek/mtk_dpi.c
index 0186e50..90fb831 100644
--- a/drivers/gpu/drm/mediatek/mtk_dpi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dpi.c
@@ -432,11 +432,16 @@ static int mtk_dpi_set_display_mode(struct mtk_dpi *dpi,
 	unsigned long pll_rate;
 	unsigned int factor;
 
+	/* let pll_rate can fix the valid range of tvdpll (1G~2GHz) */
 	pix_rate = 1000UL * mode->clock;
-	if (mode->clock <= 74000)
+	if (mode->clock <= 27000)
+		factor = 16 * 3;
+	else if (mode->clock <= 84000)
 		factor = 8 * 3;
-	else
+	else if (mode->clock <= 167000)
 		factor = 4 * 3;
+	else
+		factor = 2 * 3;
 	pll_rate = pix_rate * factor;
 
 	dev_dbg(dpi->dev, "Want PLL %lu Hz, pixel clock %lu Hz\n",
-- 
1.7.9.5




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