drm: bridge: add it66121 driver

This commit is a simple driver for bridge HMDI it66121.
The input format is RBG and there is no color conversion.
Audio, HDCP and CEC are not supported yet.
Signed-off-by: Phong LE <ple@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210419071223.2673533-3-narmstrong@baylibre.com

drivers/gpu/drm/bridge/Kconfig

@@ -101,6 +101,14 @@ config DRM_LONTIUM_LT9611UXC
 	  HDMI signals
 	  Please say Y if you have such hardware.
 
+config DRM_ITE_IT66121
+	tristate "ITE IT66121 HDMI bridge"
+	depends on OF
+	select DRM_KMS_HELPER
+	select REGMAP_I2C
+	help
+	  Support for ITE IT66121 HDMI bridge.
+
 config DRM_LVDS_CODEC
 	tristate "Transparent LVDS encoders and decoders support"
 	depends on OF

drivers/gpu/drm/bridge/Makefile

@@ -26,6 +26,7 @@ obj-$(CONFIG_DRM_TI_SN65DSI86) += ti-sn65dsi86.o
 obj-$(CONFIG_DRM_TI_TFP410) += ti-tfp410.o
 obj-$(CONFIG_DRM_TI_TPD12S015) += ti-tpd12s015.o
 obj-$(CONFIG_DRM_NWL_MIPI_DSI) += nwl-dsi.o
+obj-$(CONFIG_DRM_ITE_IT66121) += ite-it66121.o
 
 obj-y += analogix/
 obj-y += cadence/