DPI sample the data both rising and falling edge. It can reduce half data io pins.
Signed-off-by: Jitao Shi jitao.shi@mediatek.com --- drivers/gpu/drm/mediatek/mtk_dpi.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c b/drivers/gpu/drm/mediatek/mtk_dpi.c index bacd989cc9aa..743230864ba0 100644 --- a/drivers/gpu/drm/mediatek/mtk_dpi.c +++ b/drivers/gpu/drm/mediatek/mtk_dpi.c @@ -72,6 +72,7 @@ struct mtk_dpi { enum mtk_dpi_out_bit_num bit_num; enum mtk_dpi_out_channel_swap channel_swap; int refcount; + bool dual_edge; };
static inline struct mtk_dpi *mtk_dpi_from_encoder(struct drm_encoder *e) @@ -345,6 +346,13 @@ 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) { @@ -436,7 +444,8 @@ 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->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", @@ -501,6 +510,8 @@ 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->dual_edge) + mtk_dpi_enable_dual_edge(dpi); mtk_dpi_sw_reset(dpi, false);
return 0; @@ -686,6 +697,7 @@ static int mtk_dpi_probe(struct platform_device *pdev)
dpi->dev = dev; dpi->conf = (struct mtk_dpi_conf *)of_device_get_match_data(dev); + dpi->dual_edge = of_property_read_bool(dev->of_node, "dpi_dual_edge");
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); dpi->regs = devm_ioremap_resource(dev, mem);