google/kukui: Set up EC_IN_RW GPIO for ChromeOS

Set up EC_IN_RW GPIO to boot depthcharge. Without this patch,
depthcharge will fail to tell if the EC firmware is RW.

BUG=b:80501386
BRANCH=none
TEST=Boots correctly on Kukui and see in logs, that depthcharge detects
     EC_IN_RW GPIO.

Change-Id: Icb39d663f65b72e0ad54059c9590d9693106ee25
Signed-off-by: Tristan Shieh <tristan.shieh@mediatek.com>
Reviewed-on: https://review.coreboot.org/28670
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Julius Werner <jwerner@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/kukui/chromeos.c

@@ -21,12 +21,14 @@
 
 void setup_chromeos_gpios(void)
 {
+	gpio_input_pullup(EC_IN_RW);
 	gpio_input_pullup(EC_IRQ);
 }
 
 void fill_lb_gpios(struct lb_gpios *gpios)
 {
 	struct lb_gpio chromeos_gpios[] = {
+		{EC_IN_RW.id, ACTIVE_HIGH, -1, "EC in RW"},
 		{EC_IRQ.id, ACTIVE_LOW, -1, "EC interrupt"},
 	};
 	lb_add_gpios(gpios, chromeos_gpios, ARRAY_SIZE(chromeos_gpios));

src/mainboard/google/kukui/gpio.h

@@ -18,7 +18,8 @@
 
 #include <soc/gpio.h>
 
-#define EC_IRQ	GPIO(PERIPHERAL_EN1)
+#define EC_IRQ		GPIO(PERIPHERAL_EN1)
+#define EC_IN_RW	GPIO(PERIPHERAL_EN14)
 
 void setup_chromeos_gpios(void);