drm/panel: Add Kingdisplay KD097D04 panel driver

Support Kingdisplay KD097D04 9.7" 1536x2048 TFT LCD panel, it is a MIPI
dual-DSI panel.

v4-resend:
- Thierry noted missing dt-bindings for v4 but forgot that he
  already had applied them one kernel release back in
  https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ebc950fdff6d5f9250cd5a5a348af97f7d8508df
v4:
- address Philipp's comments
  - real range for usleep_range and
  - poweroff ordering in kingdisplay_panel_prepare
  - return value beautification in panel_probe
- update author naming for full name
v3:
- address Thierry's comments
  - error handling for init dsi writes in init
  - unconditionally remove the panel
  - don't use drm_panel_detach
  - a bit of variable signednes wiggling
- I did talk to ChromeOS people and the delays really should be as short
  as possible, so dropped the 100ms from the delay comments
v2:
- update timing + cmds from chromeos kernel
- new backlight API including switch to devm_of_find_backlight
- fix most of Sean Paul's comments
  enable/prepare tracking seems something all panels do
- document origins of the init sequence
- lanes per dsi interface to 4 (two interfaces). Matches how tegra
  and pending rockchip dual-dsi handle (dual-)dsi lanes
- spdx header instead of license boilerplate
Signed-off-by: Nickey Yang <nickey.yang@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Sean Paul <sean@poorly.run>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181030091528.28211-1-heiko@sntech.de

drivers/gpu/drm/panel/Kconfig

@@ -77,6 +77,17 @@ config DRM_PANEL_JDI_LT070ME05000
 	  The panel has a 1200(RGB)×1920 (WUXGA) resolution and uses
 	  24 bit per pixel.
 
+config DRM_PANEL_KINGDISPLAY_KD097D04
+	tristate "Kingdisplay kd097d04 panel"
+	depends on OF
+	depends on DRM_MIPI_DSI
+	depends on BACKLIGHT_CLASS_DEVICE
+	help
+	  Say Y here if you want to enable support for Kingdisplay kd097d04
+	  TFT-LCD modules. The panel has a 1536x2048 resolution and uses
+	  24 bit RGB per pixel. It provides a MIPI DSI interface to
+	  the host and has a built-in LED backlight.
+
 config DRM_PANEL_SAMSUNG_LD9040
 	tristate "Samsung LD9040 RGB/SPI panel"
 	depends on OF && SPI

drivers/gpu/drm/panel/Makefile

@@ -6,6 +6,7 @@ obj-$(CONFIG_DRM_PANEL_ILITEK_IL9322) += panel-ilitek-ili9322.o
 obj-$(CONFIG_DRM_PANEL_ILITEK_ILI9881C) += panel-ilitek-ili9881c.o
 obj-$(CONFIG_DRM_PANEL_INNOLUX_P079ZCA) += panel-innolux-p079zca.o
 obj-$(CONFIG_DRM_PANEL_JDI_LT070ME05000) += panel-jdi-lt070me05000.o
+obj-$(CONFIG_DRM_PANEL_KINGDISPLAY_KD097D04) += panel-kingdisplay-kd097d04.o
 obj-$(CONFIG_DRM_PANEL_LG_LG4573) += panel-lg-lg4573.o
 obj-$(CONFIG_DRM_PANEL_OLIMEX_LCD_OLINUXINO) += panel-olimex-lcd-olinuxino.o
 obj-$(CONFIG_DRM_PANEL_ORISETECH_OTM8009A) += panel-orisetech-otm8009a.o