[PATCH 3/4] drm/panel: lvds: Support data and clock polarity flags

Maxime Ripard maxime at cerno.tech
Fri Feb 14 12:24:40 UTC 2020


Add device tree properties to the panel-lvds driver to set the bus
flags properly.

Signed-off-by: Maxime Ripard <maxime at cerno.tech>
---
 drivers/gpu/drm/panel/panel-lvds.c | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-lvds.c b/drivers/gpu/drm/panel/panel-lvds.c
index 5ce3f4a2b7a1..c0d6dcd9e9fc 100644
--- a/drivers/gpu/drm/panel/panel-lvds.c
+++ b/drivers/gpu/drm/panel/panel-lvds.c
@@ -31,6 +31,8 @@ struct panel_lvds {
 	unsigned int height;
 	struct videomode video_mode;
 	unsigned int bus_format;
+	bool clk_active_low;
+	bool data_active_low;
 	bool data_mirror;
 
 	struct regulator *supply;
@@ -83,6 +85,7 @@ static int panel_lvds_get_modes(struct drm_panel *panel,
 {
 	struct panel_lvds *lvds = to_panel_lvds(panel);
 	struct drm_display_mode *mode;
+	unsigned int flags = 0;
 
 	mode = drm_mode_create(connector->dev);
 	if (!mode)
@@ -96,9 +99,23 @@ static int panel_lvds_get_modes(struct drm_panel *panel,
 	connector->display_info.height_mm = lvds->height;
 	drm_display_info_set_bus_formats(&connector->display_info,
 					 &lvds->bus_format, 1);
-	connector->display_info.bus_flags = lvds->data_mirror
-					  ? DRM_BUS_FLAG_DATA_LSB_TO_MSB
-					  : DRM_BUS_FLAG_DATA_MSB_TO_LSB;
+
+	if (lvds->data_mirror)
+		flags |= DRM_BUS_FLAG_DATA_LSB_TO_MSB;
+	else
+		flags |= DRM_BUS_FLAG_DATA_MSB_TO_LSB;
+
+	if (lvds->clk_active_low)
+		flags |= DRM_BUS_FLAG_PIXDATA_NEGEDGE;
+	else
+		flags |= DRM_BUS_FLAG_PIXDATA_POSEDGE;
+
+	if (lvds->data_active_low)
+		flags |= DRM_BUS_FLAG_DATA_LOW;
+	else
+		flags |= DRM_BUS_FLAG_DATA_HIGH;
+
+	connector->display_info.bus_flags = flags;
 
 	return 1;
 }
@@ -159,6 +176,8 @@ static int panel_lvds_parse_dt(struct panel_lvds *lvds)
 		return -EINVAL;
 	}
 
+	lvds->clk_active_low = of_property_read_bool(np, "clock-active-low");
+	lvds->data_active_low = of_property_read_bool(np, "data-active-low");
 	lvds->data_mirror = of_property_read_bool(np, "data-mirror");
 
 	return 0;
-- 
git-series 0.9.1


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