From: Junzhi Zhao <junzhi.z...@mediatek.com>
Currently, the code sets the "pll" to the desired multiple
of the pixel clock manully(4*3m 8*3,etc). The valid range
of the pll is 1G-2G, however, when the pixel clock is bigger
than 167MHz, the "pll" will be set to a invalid value( > 2G),
then the "pll" will be 2GHz, thus the pixel clock will be in
correct. Change the factor to make the "pll" be set in the
(1G, 2G) range.
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
