sunxi: Display: Add support for eDP panels connected via an anx9804 bridge

Add support for 4 1.62G lane eDP panels connected via an anx9804 bridge,
such as found on the Colombus devkit.

While at it also fix the wrong indentation of the SSD2828 Kconfig help text
in board/sunxi/Kconfig.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>

board/sunxi/Kconfig

@@ -526,7 +526,16 @@ config VIDEO_LCD_PANEL_MIPI_4_LANE_513_MBPS_VIA_SSD2828
 	select VIDEO_LCD_SSD2828
 	select VIDEO_LCD_IF_PARALLEL
 	---help---
-	 7.85" 768x1024 LCD panels, such as LG LP079X01 or AUO B079XAN01.0
+	7.85" 768x1024 LCD panels, such as LG LP079X01 or AUO B079XAN01.0
+
+config VIDEO_LCD_PANEL_EDP_4_LANE_1620M_VIA_ANX9804
+	bool "eDP 4-lane, 1.62G LCD panel via ANX9804 bridge chip"
+	select VIDEO_LCD_ANX9804
+	select VIDEO_LCD_IF_PARALLEL
+	select VIDEO_LCD_PANEL_I2C
+	---help---
+	Select this for eDP LCD panels with 4 lanes running at 1.62G,
+	connected via an ANX9804 bridge chip.
 
 config VIDEO_LCD_PANEL_HITACHI_TX18D42VM
 	bool "Hitachi tx18d42vm LCD panel"

configs/Colombus_defconfig

@@ -4,6 +4,16 @@ CONFIG_MACH_SUN6I=y
 CONFIG_DRAM_CLK=240
 CONFIG_DRAM_ZQ=251
 CONFIG_USB1_VBUS_PIN=""
+CONFIG_I2C0_ENABLE=y
+CONFIG_AXP_GPIO=y
+CONFIG_VIDEO_LCD_MODE="x:2048,y:1536,depth:24,pclk_khz:208000,le:5,ri:150,up:9,lo:24,hs:5,vs:1,sync:3,vmode:0"
+CONFIG_VIDEO_LCD_DCLK_PHASE=0
+CONFIG_VIDEO_LCD_POWER="PH27"
+CONFIG_VIDEO_LCD_BL_EN="PM1"
+CONFIG_VIDEO_LCD_BL_PWM="PH13"
+CONFIG_VIDEO_LCD_PANEL_I2C_SDA="PA23"
+CONFIG_VIDEO_LCD_PANEL_I2C_SCL="PA24"
+CONFIG_VIDEO_LCD_PANEL_EDP_4_LANE_1620M_VIA_ANX9804=y
 CONFIG_DEFAULT_DEVICE_TREE="sun6i-a31-colombus"
 # CONFIG_SYS_MALLOC_CLEAR_ON_INIT is not set
 CONFIG_SPL=y
@@ -13,4 +23,5 @@ CONFIG_SYS_EXTRA_OPTIONS="SUNXI_GMAC,RGMII"
 # CONFIG_CMD_FPGA is not set
 CONFIG_ETH_DESIGNWARE=y
 CONFIG_AXP221_ALDO1_VOLT=3300
+CONFIG_AXP221_ELDO3_VOLT=1800
 CONFIG_USB_EHCI_HCD=y

drivers/video/sunxi_display.c

@@ -15,6 +15,7 @@
 #include <asm/global_data.h>
 #include <asm/gpio.h>
 #include <asm/io.h>
+#include <axp221.h>
 #include <errno.h>
 #include <fdtdec.h>
 #include <fdt_support.h>
@@ -22,6 +23,7 @@
 #include <malloc.h>
 #include <video_fb.h>
 #include "videomodes.h"
+#include "anx9804.h"
 #include "hitachi_tx18d42vm_lcd.h"
 #include "ssd2828.h"
 
@@ -765,13 +767,17 @@ static void sunxi_lcdc_tcon0_mode_set(const struct ctfb_res_modes *mode,
 		(struct sunxi_lcdc_reg *)SUNXI_LCD0_BASE;
 	int bp, clk_delay, clk_div, clk_double, pin, total, val;
 
-	for (pin = SUNXI_GPD(0); pin <= SUNXI_GPD(27); pin++)
+	for (pin = SUNXI_GPD(0); pin <= SUNXI_GPD(27); pin++) {
 #ifdef CONFIG_VIDEO_LCD_IF_PARALLEL
 		sunxi_gpio_set_cfgpin(pin, SUNXI_GPD_LCD0);
 #endif
 #ifdef CONFIG_VIDEO_LCD_IF_LVDS
 		sunxi_gpio_set_cfgpin(pin, SUNXI_GPD_LVDS0);
 #endif
+#ifdef CONFIG_VIDEO_LCD_PANEL_EDP_4_LANE_1620M_VIA_ANX9804
+		sunxi_gpio_set_drv(pin, 3);
+#endif
+	}
 
 	sunxi_lcdc_pll_set(0, mode->pixclock_khz, &clk_div, &clk_double);
 
@@ -1208,6 +1214,17 @@ static void sunxi_mode_set(const struct ctfb_res_modes *mode,
 		break;
 	case sunxi_monitor_lcd:
 		sunxi_lcdc_panel_enable();
+		if (IS_ENABLED(CONFIG_VIDEO_LCD_PANEL_EDP_4_LANE_1620M_VIA_ANX9804)) {
+			/*
+			 * The anx9804 needs 1.8V from eldo3, we do this here
+			 * and not via CONFIG_AXP221_ELDO3 from board_init()
+			 * to avoid turning this on when using hdmi output.
+			 */
+			axp221_set_eldo(3, 1800);
+			anx9804_init(CONFIG_VIDEO_LCD_I2C_BUS, 4,
+				     ANX9804_DATA_RATE_1620M,
+				     sunxi_display.depth);
+		}
 		if (IS_ENABLED(CONFIG_VIDEO_LCD_HITACHI_TX18D42VM)) {
 			mdelay(50); /* Wait for lcd controller power on */
 			hitachi_tx18d42vm_init();

include/configs/sunxi-common.h

@@ -288,7 +288,11 @@ extern int soft_i2c_gpio_scl;
  * The amount of RAM to keep free at the top of RAM when relocating u-boot,
  * to use as framebuffer. This must be a multiple of 4096.
  */
+#ifdef CONFIG_VIDEO_LCD_PANEL_EDP_4_LANE_1620M_VIA_ANX9804
+#define CONFIG_SUNXI_MAX_FB_SIZE (12 << 20)
+#else
 #define CONFIG_SUNXI_MAX_FB_SIZE (9 << 20)
+#endif
 
 /* Do we want to initialize a simple FB? */
 #define CONFIG_VIDEO_DT_SIMPLEFB