feat: absolute positions

usb_gadget/init_usb_gadget

@@ -119,6 +119,17 @@ echo -ne \\x25\\x7F      #   LOGICAL_MAXIMUM (127)
 echo -ne \\x75\\x08      #   REPORT_SIZE (8)
 echo -ne \\x95\\x01      #   REPORT_COUNT (1)
 echo -ne \\x81\\x06      #   INPUT (Data,Var,Rel)
+
+                         #   x,y absolute coordinates
+echo -ne \\x05\\x01      #   USAGE_PAGE (Generic Desktop)
+echo -ne \\x09\\x30      #   USAGE (X)
+echo -ne \\x09\\x31      #   USAGE (Y)
+echo -ne \\x16\\x01\\xFF #   LOGICAL_MINIMUM (-255)
+echo -ne \\x26\\xFF\\x00 #   LOGICAL_MAXIMUM (255)
+echo -ne \\x75\\x10      #   REPORT_SIZE (16)
+echo -ne \\x95\\x02      #   REPORT_COUNT (2)
+echo -ne \\x81\\x02      #   INPUT (Data,Var,Abs)
+
 echo -ne \\xC0           # END_COLLECTION
 } >> "$D"
 cp "$D" "${MOUSE_FUNCTIONS_DIR}/report_desc"

zero_hid/hid/mouse.py

@@ -1,13 +1,22 @@
 from . import write as hid_write
 
 def send_mouse_event(dev, buttons, relative_x, relative_y,
-                     vertical_wheel_delta, horizontal_wheel_delta):
+                     vertical_wheel_delta, horizontal_wheel_delta,
+                     absolute_x=None, absolute_y=None):
     buf = [
         buttons,
         relative_x & 0xff,
         relative_y & 0xff,
         vertical_wheel_delta & 0xff,
         horizontal_wheel_delta & 0xff
     ]
-    hid_write.write_to_hid_interface(dev, buf)
-
+
+    if absolute_x is not None and absolute_y is not None:
+        buf.extend([
+            absolute_x & 0xff,
+            (absolute_x >> 8) & 0xff,
+            absolute_y & 0xff,
+            (absolute_y >> 8) & 0xff
+        ])
+
+    hid_write.write_to_hid_interface(dev, buf)