HID: Wacom: switch Dell canvas into highres mode

The Dell Canvas exports 2 collections for the Pen part. The only
difference between the 2 is that the default one has half the resolution
of the second one.

The Windows driver switches the tablet into the second mode, so we should
behave the same.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Jason Gerecke <jason.gerecke@wacom.com
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/wacom_sys.c

@@ -196,6 +196,13 @@ static void wacom_feature_mapping(struct hid_device *hdev,
 		kfree(data);
 		break;
 	}
+
+	if (hdev->vendor == USB_VENDOR_ID_WACOM &&
+	    hdev->product == 0x4200 /* Dell Canvas 27 */ &&
+	    field->application == HID_UP_MSVENDOR) {
+		wacom->wacom_wac.mode_report = field->report->id;
+		wacom->wacom_wac.mode_value = 2;
+	}
 }
 
 /*