diff --git a/drivers/gpu/drm/rockchip/rk618/rk618_dither.c b/drivers/gpu/drm/rockchip/rk618/rk618_dither.c
index 10e141a59bd6..40e6afd6ef99 100644
--- a/drivers/gpu/drm/rockchip/rk618/rk618_dither.c
+++ b/drivers/gpu/drm/rockchip/rk618/rk618_dither.c
@@ -25,8 +25,19 @@ void rk618_frc_dither_disable(struct rk618 *rk618)
 }
 EXPORT_SYMBOL_GPL(rk618_frc_dither_disable);
 
-void rk618_frc_dither_enable(struct rk618 *rk618)
+void rk618_frc_dither_enable(struct rk618 *rk618, u32 bus_format)
 {
+	switch (bus_format) {
+	case MEDIA_BUS_FMT_RGB666_1X18:
+		regmap_write(rk618->regmap, RK618_FRC_REG, FRC_OUT_MODE_RGB666);
+		break;
+	case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
+		regmap_write(rk618->regmap, RK618_FRC_REG, FRC_OUT_MODE_RGB888);
+		break;
+	default:
+		return;
+	}
+
 	regmap_write(rk618->regmap, RK618_FRC_REG, FRC_DITHER_ENABLE);
 }
 EXPORT_SYMBOL_GPL(rk618_frc_dither_enable);
diff --git a/drivers/gpu/drm/rockchip/rk618/rk618_dither.h b/drivers/gpu/drm/rockchip/rk618/rk618_dither.h
index af12fbdb9ab6..2e1e4d793da0 100644
--- a/drivers/gpu/drm/rockchip/rk618/rk618_dither.h
+++ b/drivers/gpu/drm/rockchip/rk618/rk618_dither.h
@@ -8,10 +8,11 @@
 #ifndef _RK618_DITHER_H_
 #define _RK618_DITHER_H_
 
+#include <uapi/linux/media-bus-format.h>
 #include <linux/mfd/rk618.h>
 
 void rk618_frc_dither_disable(struct rk618 *rk618);
-void rk618_frc_dither_enable(struct rk618 *rk618);
+void rk618_frc_dither_enable(struct rk618 *rk618, u32 bus_format);
 void rk618_frc_dclk_invert(struct rk618 *rk618);
 
 #endif
diff --git a/drivers/gpu/drm/rockchip/rk618/rk618_rgb.c b/drivers/gpu/drm/rockchip/rk618/rk618_rgb.c
index 1d0fed11525f..6de7df9daf3e 100644
--- a/drivers/gpu/drm/rockchip/rk618/rk618_rgb.c
+++ b/drivers/gpu/drm/rockchip/rk618/rk618_rgb.c
@@ -94,12 +94,29 @@ static const struct drm_connector_funcs rk618_rgb_connector_funcs = {
 static void rk618_rgb_bridge_enable(struct drm_bridge *bridge)
 {
 	struct rk618_rgb *rgb = bridge_to_rgb(bridge);
+	struct drm_connector *connector = &rgb->connector;
+	struct drm_display_info *info = &connector->display_info;
+	u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
 	u32 value;
 
 	clk_prepare_enable(rgb->clock);
 
 	rk618_frc_dclk_invert(rgb->parent);
 
+	if (info->num_bus_formats)
+		bus_format = info->bus_formats[0];
+
+	switch (bus_format) {
+	case MEDIA_BUS_FMT_RGB666_1X18:
+	case MEDIA_BUS_FMT_RGB666_1X24_CPADHI:
+		rk618_frc_dither_enable(rgb->parent, bus_format);
+		break;
+	case MEDIA_BUS_FMT_RGB888_1X24:
+	default:
+		rk618_frc_dither_disable(rgb->parent);
+		break;
+	}
+
 	dev_dbg(rgb->dev, "id=%d\n", rgb->id);
 
 	if (rgb->id) {