HID: wacom: generic: Introduce pad support

As with usages for the pen, the Custom HID specificiation includes
usages for the pad. Here we add functions to map and handle most
of the pad usages present on the MobileStudio Pro.

Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/wacom_wac.h b/drivers/hid/wacom_wac.h
index b4c3c64..1f7c4a8 100644
--- a/drivers/hid/wacom_wac.h
+++ b/drivers/hid/wacom_wac.h
@@ -86,19 +86,34 @@
 #define WACOM_DEVICETYPE_DIRECT         0x0010
 
 #define WACOM_HID_UP_WACOMDIGITIZER     0xff0d0000
+#define WACOM_HID_SP_PAD                0x00040000
+#define WACOM_HID_SP_BUTTON             0x00090000
 #define WACOM_HID_SP_DIGITIZER          0x000d0000
 #define WACOM_HID_SP_DIGITIZERINFO      0x00100000
 #define WACOM_HID_WD_DIGITIZER          (WACOM_HID_UP_WACOMDIGITIZER | 0x01)
 #define WACOM_HID_WD_SENSE              (WACOM_HID_UP_WACOMDIGITIZER | 0x36)
+#define WACOM_HID_WD_DIGITIZERFNKEYS    (WACOM_HID_UP_WACOMDIGITIZER | 0x39)
 #define WACOM_HID_WD_SERIALHI           (WACOM_HID_UP_WACOMDIGITIZER | 0x5c)
 #define WACOM_HID_WD_TOOLTYPE           (WACOM_HID_UP_WACOMDIGITIZER | 0x77)
 #define WACOM_HID_WD_DISTANCE           (WACOM_HID_UP_WACOMDIGITIZER | 0x0132)
+#define WACOM_HID_WD_TOUCHRING          (WACOM_HID_UP_WACOMDIGITIZER | 0x0138)
+#define WACOM_HID_WD_TOUCHRINGSTATUS    (WACOM_HID_UP_WACOMDIGITIZER | 0x0139)
+#define WACOM_HID_WD_ACCELEROMETER_X    (WACOM_HID_UP_WACOMDIGITIZER | 0x0401)
+#define WACOM_HID_WD_ACCELEROMETER_Y    (WACOM_HID_UP_WACOMDIGITIZER | 0x0402)
+#define WACOM_HID_WD_ACCELEROMETER_Z    (WACOM_HID_UP_WACOMDIGITIZER | 0x0403)
+#define WACOM_HID_WD_EXPRESSKEY00       (WACOM_HID_UP_WACOMDIGITIZER | 0x0910)
+#define WACOM_HID_WD_BUTTONHOME         (WACOM_HID_UP_WACOMDIGITIZER | 0x0990)
+#define WACOM_HID_WD_BUTTONUP           (WACOM_HID_UP_WACOMDIGITIZER | 0x0991)
+#define WACOM_HID_WD_BUTTONDOWN         (WACOM_HID_UP_WACOMDIGITIZER | 0x0992)
+#define WACOM_HID_WD_BUTTONLEFT         (WACOM_HID_UP_WACOMDIGITIZER | 0x0993)
+#define WACOM_HID_WD_BUTTONRIGHT        (WACOM_HID_UP_WACOMDIGITIZER | 0x0994)
 #define WACOM_HID_WD_FINGERWHEEL        (WACOM_HID_UP_WACOMDIGITIZER | 0x0d03)
 #define WACOM_HID_WD_OFFSETLEFT         (WACOM_HID_UP_WACOMDIGITIZER | 0x0d30)
 #define WACOM_HID_WD_OFFSETTOP          (WACOM_HID_UP_WACOMDIGITIZER | 0x0d31)
 #define WACOM_HID_WD_OFFSETRIGHT        (WACOM_HID_UP_WACOMDIGITIZER | 0x0d32)
 #define WACOM_HID_WD_OFFSETBOTTOM       (WACOM_HID_UP_WACOMDIGITIZER | 0x0d33)
 #define WACOM_HID_WD_DATAMODE           (WACOM_HID_UP_WACOMDIGITIZER | 0x1002)
+#define WACOM_HID_WD_DIGITIZERINFO      (WACOM_HID_UP_WACOMDIGITIZER | 0x1013)
 #define WACOM_HID_UP_G9                 0xff090000
 #define WACOM_HID_G9_PEN                (WACOM_HID_UP_G9 | 0x02)
 #define WACOM_HID_G9_TOUCHSCREEN        (WACOM_HID_UP_G9 | 0x11)
@@ -106,6 +121,10 @@
 #define WACOM_HID_G11_PEN               (WACOM_HID_UP_G11 | 0x02)
 #define WACOM_HID_G11_TOUCHSCREEN       (WACOM_HID_UP_G11 | 0x11)
 
+#define WACOM_PAD_FIELD(f)	(((f)->physical == HID_DG_TABLETFUNCTIONKEY) || \
+				 ((f)->physical == WACOM_HID_WD_DIGITIZERFNKEYS) || \
+				 ((f)->physical == WACOM_HID_WD_DIGITIZERINFO))
+
 #define WACOM_PEN_FIELD(f)	(((f)->logical == HID_DG_STYLUS) || \
 				 ((f)->physical == HID_DG_STYLUS) || \
 				 ((f)->physical == HID_DG_PEN) || \