mb/google/myst: Declare CrOS GPIOs

Declare CrOS GPIOs for Myst, add relevant defines needed by chromeOS for
additional control GPIOs.

BUG=b:270616013
TEST=builds

Signed-off-by: Jon Murphy <jpmurphy@google.com>
Change-Id: Ie876883d6ee2e3bc6324c038cefee12d99702dc9
Reviewed-on: https://review.coreboot.org/c/coreboot/+/74096
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
Reviewed-by: Karthik Ramasubramanian <kramasub@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/mainboard/google/myst/chromeos.c b/src/mainboard/google/myst/chromeos.c
new file mode 100644
index 0000000..9f4a3cb
--- /dev/null
+++ b/src/mainboard/google/myst/chromeos.c
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include <baseboard/gpio.h>
+#include <vendorcode/google/chromeos/chromeos.h>
+
+static const struct cros_gpio cros_gpios[] = {
+	CROS_GPIO_REC_AL(CROS_GPIO_VIRTUAL, GPIO_DEVICE_NAME),
+	CROS_GPIO_WP_AL(CROS_WP_GPIO, GPIO_DEVICE_NAME),
+};
+DECLARE_CROS_GPIOS(cros_gpios);
diff --git a/src/mainboard/google/myst/variants/baseboard/include/baseboard/gpio.h b/src/mainboard/google/myst/variants/baseboard/include/baseboard/gpio.h
index b94afac..a6683fd 100644
--- a/src/mainboard/google/myst/variants/baseboard/include/baseboard/gpio.h
+++ b/src/mainboard/google/myst/variants/baseboard/include/baseboard/gpio.h
@@ -3,4 +3,9 @@
 #ifndef __BASEBOARD_GPIO_H__
 #define __BASEBOARD_GPIO_H__
 
+#include <gpio.h>
+
+/* SPI Write protect */
+#define CROS_WP_GPIO GPIO_139
+
 #endif /* __BASEBOARD_GPIO_H__ */