DPI sample the data both rising and falling edge.
It can reduce half data io pins.

Signed-off-by: Jitao Shi <[email protected]>
---
 drivers/gpu/drm/mediatek/mtk_dpi.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c 
b/drivers/gpu/drm/mediatek/mtk_dpi.c
index 22e68a100e7b..ccef3ac1c560 100644
--- a/drivers/gpu/drm/mediatek/mtk_dpi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dpi.c
@@ -117,6 +117,7 @@ struct mtk_dpi_conf {
        unsigned int (*cal_factor)(int clock);
        u32 reg_h_fre_con;
        bool edge_sel_en;
+       bool dual_edge;
 };
 
 static void mtk_dpi_mask(struct mtk_dpi *dpi, u32 offset, u32 val, u32 mask)
@@ -353,6 +354,13 @@ static void mtk_dpi_config_disable_edge(struct mtk_dpi 
*dpi)
                mtk_dpi_mask(dpi, dpi->conf->reg_h_fre_con, 0, EDGE_SEL_EN);
 }
 
+static void mtk_dpi_enable_dual_edge(struct mtk_dpi *dpi)
+{
+       mtk_dpi_mask(dpi, DPI_DDR_SETTING, DDR_EN | DDR_4PHASE,
+                    DDR_EN | DDR_4PHASE);
+       mtk_dpi_mask(dpi, DPI_OUTPUT_SETTING, EDGE_SEL, EDGE_SEL);
+}
+
 static void mtk_dpi_config_color_format(struct mtk_dpi *dpi,
                                        enum mtk_dpi_out_color_format format)
 {
@@ -444,7 +452,8 @@ static int mtk_dpi_set_display_mode(struct mtk_dpi *dpi,
        pll_rate = clk_get_rate(dpi->tvd_clk);
 
        vm.pixelclock = pll_rate / factor;
-       clk_set_rate(dpi->pixel_clk, vm.pixelclock);
+       clk_set_rate(dpi->pixel_clk,
+                    vm.pixelclock * (dpi->conf->dual_edge ? 2 : 1));
        vm.pixelclock = clk_get_rate(dpi->pixel_clk);
 
        dev_dbg(dpi->dev, "Got  PLL %lu Hz, pixel clock %lu Hz\n",
@@ -509,6 +518,8 @@ static int mtk_dpi_set_display_mode(struct mtk_dpi *dpi,
        mtk_dpi_config_color_format(dpi, dpi->color_format);
        mtk_dpi_config_2n_h_fre(dpi);
        mtk_dpi_config_disable_edge(dpi);
+       if (dpi->conf->dual_edge)
+               mtk_dpi_enable_dual_edge(dpi);
        mtk_dpi_sw_reset(dpi, false);
 
        return 0;
-- 
2.21.0

_______________________________________________
dri-devel mailing list
[email protected]
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Reply via email to