mb/google/geralt: Move backlight-related functions to common panel.c

These backlight related functions can be reused in other variants, move
them out to the panel.c. Also the panel_geralt.c should be used for
Geralt, enable it on Geralt board only.

BUG=b:308968270
TEST=emerge-geralt coreboot
BRANCH=None

Change-Id: I5d4035d5f480551c428c450826e23bf77f2fe08a
Signed-off-by: Ruihai Zhou <zhouruihai@huaqin.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/78955
Reviewed-by: Yidi Lin <yidilin@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: cong yang <yangcong5@huaqin.corp-partner.google.com>
diff --git a/src/mainboard/google/geralt/panel.c b/src/mainboard/google/geralt/panel.c
index 3174870..e25b5cb 100644
--- a/src/mainboard/google/geralt/panel.c
+++ b/src/mainboard/google/geralt/panel.c
@@ -5,6 +5,7 @@
 #include <console/console.h>
 #include <edid.h>
 #include <gpio.h>
+#include <identity.h>
 #include <soc/gpio_common.h>
 #include <string.h>
 
@@ -35,6 +36,13 @@
 		printk(BIOS_ERR, "Missing %s in CBFS.\n", cbfs_name);
 }
 
+struct panel_description __weak *get_panel_description(uint32_t panel_id)
+{
+	printk(BIOS_WARNING, "%s: %s: the panel configuration is not ready\n",
+	       __func__, mainboard_part_number);
+	return NULL;
+}
+
 struct panel_description *get_active_panel(void)
 {
 	uint32_t active_panel_id = panel_id();
@@ -66,3 +74,38 @@
 	}
 	return panel;
 }
+
+void configure_mipi_pwm_backlight(void)
+{
+	gpio_output(GPIO_AP_DISP_BKLTEN, 0);
+	gpio_output(GPIO_MIPI_BL_PWM_1V8, 0);
+}
+
+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_BL_PWM_1V8.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));
+}