[v2,PATCH 1/3] drm/mediatek: dpi dual edge sample mode support

From: Rex-BC Chen
Date: Wed Apr 14 2021 - 09:35:45 EST


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

Signed-off-by: Jitao Shi <jitao.shi@xxxxxxxxxxxx>
Signed-off-by: Rex-BC Chen <rex-bc.chen@xxxxxxxxxxxx>
---
drivers/gpu/drm/mediatek/mtk_dpi.c | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c b/drivers/gpu/drm/mediatek/mtk_dpi.c
index b05f900d9322..21a3a7b78835 100644
--- a/drivers/gpu/drm/mediatek/mtk_dpi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dpi.c
@@ -83,6 +83,7 @@ struct mtk_dpi {
struct pinctrl *pinctrl;
struct pinctrl_state *pins_gpio;
struct pinctrl_state *pins_dpi;
+ bool ddr_edge_sel;
int refcount;
};

@@ -121,6 +122,7 @@ 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)
@@ -380,6 +382,15 @@ static void mtk_dpi_config_color_format(struct mtk_dpi *dpi,
}
}

+static void mtk_dpi_dual_edge(struct mtk_dpi *dpi)
+{
+ if (dpi->conf->dual_edge) {
+ mtk_dpi_mask(dpi, DPI_DDR_SETTING, DDR_EN | DDR_4PHASE,
+ DDR_EN | DDR_4PHASE);
+ mtk_dpi_mask(dpi, DPI_OUTPUT_SETTING, dpi->ddr_edge_sel ? EDGE_SEL : 0, EDGE_SEL);
+ }
+}
+
static void mtk_dpi_power_off(struct mtk_dpi *dpi)
{
if (WARN_ON(dpi->refcount == 0))
@@ -518,6 +529,7 @@ static int mtk_dpi_set_display_mode(struct mtk_dpi *dpi,
mtk_dpi_config_yc_map(dpi, dpi->yc_map);
mtk_dpi_config_color_format(dpi, dpi->color_format);
mtk_dpi_config_2n_h_fre(dpi);
+ mtk_dpi_dual_edge(dpi);
mtk_dpi_config_disable_edge(dpi);
mtk_dpi_sw_reset(dpi, false);

--
2.18.0