extcon: Add EXTCON_DISP_DP and the property for USB Type-C

Add EXTCON_DISP_DP for the Display external connector. For Type-C
connector the DisplayPort can work as an Alternate Mode(VESA DisplayPort
Alt Mode on USB Type-C Standard). The Type-C support both normal
and flipped orientation, so add a property to extcon.

Signed-off-by: Chris Zhong <zyw@rock-chips.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Chris Zhong <zyw@rock-chips.com>
Tested-by: Guenter Roeck <groeck@chromium.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
diff --git a/drivers/extcon/extcon.c b/drivers/extcon/extcon.c
index 8fde4be..a0a1eea 100644
--- a/drivers/extcon/extcon.c
+++ b/drivers/extcon/extcon.c
@@ -157,6 +157,11 @@
 		.id = EXTCON_DISP_VGA,
 		.name = "VGA",
 	},
+	[EXTCON_DISP_DP] = {
+		.type = EXTCON_TYPE_DISP | EXTCON_TYPE_USB,
+		.id = EXTCON_DISP_DP,
+		.name = "DP",
+	},
 
 	/* Miscellaneous external connector */
 	[EXTCON_DOCK] = {
diff --git a/include/linux/extcon.h b/include/linux/extcon.h
index 162c46a..ad7a160 100644
--- a/include/linux/extcon.h
+++ b/include/linux/extcon.h
@@ -69,6 +69,7 @@
 #define EXTCON_DISP_MHL		41	/* Mobile High-Definition Link */
 #define EXTCON_DISP_DVI		42	/* Digital Visual Interface */
 #define EXTCON_DISP_VGA		43	/* Video Graphics Array */
+#define EXTCON_DISP_DP		44	/* Display Port */
 
 /* Miscellaneous external connector */
 #define EXTCON_DOCK		60
@@ -102,11 +103,16 @@
  * @type:	integer (intval)
  * @value:	0 (low) or 1 (high)
  * @default:	0 (low)
+ * - EXTCON_PROP_USB_TYPEC_POLARITY
+ * @type:	integer (intval)
+ * @value:	0 (normal) or 1 (flip)
+ * @default:	0 (normal)
  */
 #define EXTCON_PROP_USB_VBUS		0
+#define EXTCON_PROP_USB_TYPEC_POLARITY	1
 
 #define EXTCON_PROP_USB_MIN		0
-#define EXTCON_PROP_USB_MAX		0
+#define EXTCON_PROP_USB_MAX		1
 #define EXTCON_PROP_USB_CNT	(EXTCON_PROP_USB_MAX - EXTCON_PROP_USB_MIN + 1)
 
 /* Properties of EXTCON_TYPE_CHG. */