drm/bridge: Add Analogix anx6345 support

The ANX6345 is an ultra-low power DisplayPower/eDP transmitter designed
for portable devices. This driver adds initial support for RGB to eDP
mode, without HPD and interrupts.

This is a configuration usually seen in eDP applications.
Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20191107135220.590D968BFE@verein.lst.de

drivers/gpu/drm/bridge/analogix/Kconfig

 # SPDX-License-Identifier: GPL-2.0-only
+config DRM_ANALOGIX_ANX6345
+	tristate "Analogix ANX6345 bridge"
+	select DRM_ANALOGIX_DP
+	select DRM_KMS_HELPER
+	select REGMAP_I2C
+	help
+	  ANX6345 is an ultra-low Full-HD DisplayPort/eDP
+	  transmitter designed for portable devices. The
+	  ANX6345 transforms the LVTTL RGB output of an
+	  application processor to eDP or DisplayPort.
+
 config DRM_ANALOGIX_ANX78XX
 	tristate "Analogix ANX78XX bridge"
+	select DRM_ANALOGIX_DP
 	select DRM_KMS_HELPER
 	select REGMAP_I2C
 	help

drivers/gpu/drm/bridge/analogix/Makefile

 # SPDX-License-Identifier: GPL-2.0-only
 analogix_dp-objs := analogix_dp_core.o analogix_dp_reg.o analogix-i2c-dptx.o
+obj-$(CONFIG_DRM_ANALOGIX_ANX6345) += analogix-anx6345.o
 obj-$(CONFIG_DRM_ANALOGIX_ANX78XX) += analogix-anx78xx.o
 obj-$(CONFIG_DRM_ANALOGIX_DP) += analogix_dp.o