drm/panel: ws2401: Add driver for WideChips WS2401

This adds a driver for panels based on the WideChips WS2401 display
controller. This display controller is used in the Samsung LMS380KF01
display found in the Samsung GT-I8160 (Codina) mobile phone and
possibly others.

As is common with Samsung displays manufacturer commands are necessary
to configure the display to a working state.

The display optionally supports internal backlight control, but can
also use an external backlight.

This driver re-uses the DBI infrastructure to communicate with the
display.

Cc: phone-devel@vger.kernel.org
Cc: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210714225002.1065107-2-linus.walleij@linaro.org

MAINTAINERS

@@ -5969,6 +5969,13 @@ T:	git git://anongit.freedesktop.org/drm/drm-misc
 F:	drivers/gpu/drm/vmwgfx/
 F:	include/uapi/drm/vmwgfx_drm.h
 
+DRM DRIVER FOR WIDECHIPS WS2401 PANELS
+M:	Linus Walleij <linus.walleij@linaro.org>
+S:	Maintained
+T:	git git://anongit.freedesktop.org/drm/drm-misc
+F:	Documentation/devicetree/bindings/display/panel/samsung,lms380kf01.yaml
+F:	drivers/gpu/drm/panel/panel-widechips-ws2401.c
+
 DRM DRIVERS
 M:	David Airlie <airlied@linux.ie>
 M:	Daniel Vetter <daniel@ffwll.ch>

drivers/gpu/drm/panel/Kconfig

@@ -574,6 +574,16 @@ config DRM_PANEL_VISIONOX_RM69299
 	  Say Y here if you want to enable support for Visionox
 	  RM69299  DSI Video Mode panel.
 
+config DRM_PANEL_WIDECHIPS_WS2401
+	tristate "Widechips WS2401 DPI panel driver"
+	depends on SPI && GPIOLIB
+	depends on BACKLIGHT_CLASS_DEVICE
+	select DRM_MIPI_DBI
+	help
+	  Say Y here if you want to enable support for the Widechips WS2401 DPI
+	  480x800 display controller used in panels such as Samsung LMS380KF01.
+	  This display is used in the Samsung Galaxy Ace 2 GT-I8160 (Codina).
+
 config DRM_PANEL_XINPENG_XPP055C272
 	tristate "Xinpeng XPP055C272 panel driver"
 	depends on OF

drivers/gpu/drm/panel/Makefile

@@ -60,4 +60,5 @@ obj-$(CONFIG_DRM_PANEL_TPO_TD043MTEA1) += panel-tpo-td043mtea1.o
 obj-$(CONFIG_DRM_PANEL_TPO_TPG110) += panel-tpo-tpg110.o
 obj-$(CONFIG_DRM_PANEL_TRULY_NT35597_WQXGA) += panel-truly-nt35597.o
 obj-$(CONFIG_DRM_PANEL_VISIONOX_RM69299) += panel-visionox-rm69299.o
+obj-$(CONFIG_DRM_PANEL_WIDECHIPS_WS2401) += panel-widechips-ws2401.o
 obj-$(CONFIG_DRM_PANEL_XINPENG_XPP055C272) += panel-xinpeng-xpp055c272.o