extcon: palmas: Add the support for VBUS detection by using GPIO

This patch support for VBUS detection by using GPIO pin.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
diff --git a/include/linux/mfd/palmas.h b/include/linux/mfd/palmas.h
index c800dbc..5c9a1d4 100644
--- a/include/linux/mfd/palmas.h
+++ b/include/linux/mfd/palmas.h
@@ -580,7 +580,9 @@
 	int vbus_irq;
 
 	int gpio_id_irq;
+	int gpio_vbus_irq;
 	struct gpio_desc *id_gpiod;
+	struct gpio_desc *vbus_gpiod;
 	unsigned long sw_debounce_jiffies;
 	struct delayed_work wq_detectid;
 
@@ -589,6 +591,7 @@
 	bool enable_vbus_detection;
 	bool enable_id_detection;
 	bool enable_gpio_id_detection;
+	bool enable_gpio_vbus_detection;
 };
 
 #define comparator_to_palmas(x) container_of((x), struct palmas_usb, comparator)