HID: wacom: Add support for I2C connected devices

Lenovo Thinkpad 10 has wacom digitizer connected as a I2C-HID device. Add
generic support for this.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/wacom_wac.c

@@ -2969,6 +2969,10 @@ static const struct wacom_features wacom_features_HID_ANY_ID =
 	HID_DEVICE(BUS_BLUETOOTH, HID_GROUP_WACOM, USB_VENDOR_ID_WACOM, prod),\
 	.driver_data = (kernel_ulong_t)&wacom_features_##prod
 
+#define I2C_DEVICE_WACOM(prod)						\
+	HID_DEVICE(BUS_I2C, HID_GROUP_WACOM, USB_VENDOR_ID_WACOM, prod),\
+	.driver_data = (kernel_ulong_t)&wacom_features_##prod
+
 #define USB_DEVICE_LENOVO(prod)					\
 	HID_USB_DEVICE(USB_VENDOR_ID_LENOVO, prod),			\
 	.driver_data = (kernel_ulong_t)&wacom_features_##prod
@@ -3113,6 +3117,7 @@ const struct hid_device_id wacom_ids[] = {
 	{ USB_DEVICE_LENOVO(0x6004) },
 
 	{ USB_DEVICE_WACOM(HID_ANY_ID) },
+	{ I2C_DEVICE_WACOM(HID_ANY_ID) },
 	{ }
 };
 MODULE_DEVICE_TABLE(hid, wacom_ids);