HID: wacom: generic: add 3 tablet touch keys

This patch add support to the 3 touch keys on Wacom Cintiq Pro. These touch
keys are in the middle of the other two keys on the top edge of the tablet.

Signed-off-by: Ping Cheng <[e-mail]>
Reviewed-by: Benjamin Tissoires <[e-mail]>
Tested-by: Aaron Armstrong Skomra <[e-mail]>
Acked-by: Dmitry Torokhov <[e-mail]>
Signed-off-by: Jiri Kosina <[e-mail]>

drivers/hid/wacom_wac.c

···
 		wacom_map_usage(input, usage, field, EV_ABS, ABS_WHEEL, 0);
 		features->device_type |= WACOM_DEVICETYPE_PAD;
 		break;
+	case WACOM_HID_WD_BUTTONCONFIG:
+		wacom_map_usage(input, usage, field, EV_KEY, KEY_BUTTONCONFIG, 0);
+		features->device_type |= WACOM_DEVICETYPE_PAD;
+		break;
+	case WACOM_HID_WD_ONSCREEN_KEYBOARD:
+		wacom_map_usage(input, usage, field, EV_KEY, KEY_ONSCREEN_KEYBOARD, 0);
+		features->device_type |= WACOM_DEVICETYPE_PAD;
+		break;
+	case WACOM_HID_WD_CONTROLPANEL:
+		wacom_map_usage(input, usage, field, EV_KEY, KEY_CONTROLPANEL, 0);
+		features->device_type |= WACOM_DEVICETYPE_PAD;
+		break;
 	}
 
 	switch (equivalent_usage & 0xfffffff0) {

drivers/hid/wacom_wac.h

···
 #define WACOM_HID_WD_BATTERY_LEVEL      (WACOM_HID_UP_WACOMDIGITIZER | 0x043b)
 #define WACOM_HID_WD_EXPRESSKEY00       (WACOM_HID_UP_WACOMDIGITIZER | 0x0910)
 #define WACOM_HID_WD_EXPRESSKEYCAP00    (WACOM_HID_UP_WACOMDIGITIZER | 0x0950)
+#define WACOM_HID_WD_CONTROLPANEL       (WACOM_HID_UP_WACOMDIGITIZER | 0x0982)
+#define WACOM_HID_WD_ONSCREEN_KEYBOARD  (WACOM_HID_UP_WACOMDIGITIZER | 0x0983)
+#define WACOM_HID_WD_BUTTONCONFIG       (WACOM_HID_UP_WACOMDIGITIZER | 0x0986)
 #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)

include/uapi/linux/input-event-codes.h

···
  * e.g. teletext or data broadcast application (MHEG, MHP, HbbTV, etc.)
  */
 #define KEY_DATA			0x277
+#define KEY_ONSCREEN_KEYBOARD		0x278
 
 #define BTN_TRIGGER_HAPPY		0x2c0
 #define BTN_TRIGGER_HAPPY1		0x2c0