HID: hid-multitouch: add support for Elo TouchSystems 2515 IntelliTouch Plus

This patch adds support for Elo TouchSystems 2515 IntelliTouch Plus
that can be found in Lenovo A700 all-in-one.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@enac.fr>
Tested-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index ef33e2d..3bc8de6 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -92,6 +92,7 @@
 #define MT_CLS_3M				7
 #define MT_CLS_CONFIDENCE			8
 #define MT_CLS_CONFIDENCE_MINUS_ONE		9
+#define MT_CLS_DUAL_NSMU_CONTACTID		10
 
 #define MT_DEFAULT_MAXCONTACT	10
 
@@ -163,6 +164,10 @@
 		.sn_height = 128 },
 	{ .name = MT_CLS_CONFIDENCE,
 		.quirks = MT_QUIRK_VALID_IS_CONFIDENCE },
+	{ .name = MT_CLS_DUAL_NSMU_CONTACTID,
+		.quirks = MT_QUIRK_NOT_SEEN_MEANS_UP |
+			MT_QUIRK_SLOT_IS_CONTACTID,
+		.maxcontacts = 2 },
 
 	{ }
 };
@@ -584,6 +589,11 @@
 		HID_USB_DEVICE(USB_VENDOR_ID_CYPRESS,
 			USB_DEVICE_ID_CYPRESS_TRUETOUCH) },
 
+	/* Elo TouchSystems IntelliTouch Plus panel */
+	{ .driver_data = MT_CLS_DUAL_NSMU_CONTACTID,
+		HID_USB_DEVICE(USB_VENDOR_ID_ELO,
+			USB_DEVICE_ID_ELO_TS2515) },
+
 	/* GeneralTouch panel */
 	{ .driver_data = MT_CLS_DUAL_INRANGE_CONTACTNUMBER,
 		HID_USB_DEVICE(USB_VENDOR_ID_GENERAL_TOUCH,