mb/google/geralt: Pass GPIOs to allow backlight control in payloads

There are two ways to control backlight in geralt:
1. MIPI/eDP panel => control backlight via the GPIOs.
   (`backlight chip enable` and `PWM dimming control`)
2. eDP OLED panel => enable backlight via `backlight chip enable` and
   control dimming over AUX.

For MIPI/eDP panels(#1), both "backlight enable" and "PWM control" GPIOs
will be passed from coreboot. For eDP OLED panel(#2), only the
"backlight enable" GPIO will be passed. If depthcharge successfully gets
the GPIOs, it will use them to control backlight.

BUG=b:244208960
TEST=test firmware display pass for eDP and MIPI panels on MT8188 EVB

Change-Id: I866fa219722241008e2b0d566b29edf2f6d9321f
Signed-off-by: Bo-Chen Chen <rex-bc.chen@mediatek.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/70744
Reviewed-by: Yidi Lin <yidilin@google.com>
Reviewed-by: Yu-Ping Wu <yupingso@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/geralt/chromeos.c

@@ -6,6 +6,7 @@
 #include <security/tpm/tis.h>
 
 #include "gpio.h"
+#include "panel.h"
 
 void setup_chromeos_gpios(void)
 {
@@ -28,6 +29,8 @@ void fill_lb_gpios(struct lb_gpios *gpios)
 		{GPIO_EN_SPKR.id, ACTIVE_HIGH, -1, "speaker enable"},
 	};
 	lb_add_gpios(gpios, chromeos_gpios, ARRAY_SIZE(chromeos_gpios));
+
+	fill_lp_backlight_gpios(gpios);
 }
 
 int tis_plat_irq_status(void)

src/mainboard/google/geralt/panel.h

@@ -3,6 +3,7 @@
 #ifndef __MAINBOARD_GOOGLE_GERALT_PANEL_H__
 #define __MAINBOARD_GOOGLE_GERALT_PANEL_H__
 
+#include <boot/coreboot_tables.h>
 #include <mipi/panel.h>
 #include <soc/ddp.h>
 
@@ -12,8 +13,10 @@ struct panel_description {
 	void (*power_on)(void);
 	void (*configure_panel_backlight)(void);
 	enum disp_path_sel disp_path;
+	bool pwm_ctrl_gpio;
 };
 
+void fill_lp_backlight_gpios(struct lb_gpios *gpios);
 uint32_t panel_id(void);
 struct panel_description *get_panel_description(uint32_t panel_id);
 struct panel_description *get_active_panel(void);

src/mainboard/google/geralt/panel_geralt.c

@@ -1,6 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 
 #include <boardid.h>
+#include <boot/coreboot_tables.h>
 #include <gpio.h>
 #include <soc/gpio_common.h>
 #include <string.h>
@@ -35,12 +36,14 @@ static struct panel_description panels[] = {
 		.power_on = power_on_mipi_boe_nv110c9m_l60,
 		.configure_panel_backlight = configure_mipi_pwm_backlight,
 		.disp_path = DISP_PATH_MIPI,
+		.pwm_ctrl_gpio = true,
 	},
 	[11] = {
 		.name = "MUTTO_B152731E1",
 		.power_on = power_on_edp_mutto_b152731e1,
 		.configure_panel_backlight = configure_edp_aux_backlight,
 		.disp_path = DISP_PATH_EDP,
+		.pwm_ctrl_gpio = false,
 	},
 };
 
@@ -51,3 +54,32 @@ struct panel_description *get_panel_description(uint32_t panel_id)
 
 	return &panels[panel_id];
 }
+
+void fill_lp_backlight_gpios(struct lb_gpios *gpios)
+{
+	struct panel_description *panel = get_active_panel();
+	if (!panel || panel->disp_path == DISP_PATH_NONE)
+		return;
+
+	struct lb_gpio mipi_pwm_gpios[] = {
+		{GPIO_MIPI_PANEL_BL_PWM.id, ACTIVE_HIGH, -1, "PWM control"},
+	};
+
+	struct lb_gpio edp_pwm_gpios[] = {
+		{GPIO_EDP_BL_PWM_1V8.id, ACTIVE_HIGH, -1, "PWM control"},
+	};
+
+	if (panel->pwm_ctrl_gpio) {
+		/* PWM control for typical eDP and MIPI panels */
+		if (panel->disp_path == DISP_PATH_MIPI)
+			lb_add_gpios(gpios, mipi_pwm_gpios, ARRAY_SIZE(mipi_pwm_gpios));
+		else
+			lb_add_gpios(gpios, edp_pwm_gpios, ARRAY_SIZE(edp_pwm_gpios));
+	}
+
+	struct lb_gpio backlight_gpios[] = {
+		{GPIO_AP_DISP_BKLTEN.id, ACTIVE_HIGH, -1, "backlight enable"},
+	};
+
+	lb_add_gpios(gpios, backlight_gpios, ARRAY_SIZE(backlight_gpios));
+}