Fix AttributeError in LcdCommRevC: sub_revision/rom_version undefined until InitializeComm()

library/lcd/lcd_comm_rev_c.py

@@ -130,6 +130,21 @@ def __init__(self, com_port: str = "AUTO", display_width: int = 480, display_hei
                  update_queue: Optional[queue.Queue] = None):
         logger.debug("HW revision: C")
         LcdComm.__init__(self, com_port, display_width, display_height, update_queue)
+
+        self.rom_version = 87  # Default ROM version, actual value detected by _hello() on InitializeComm()
+
+        # Note: ID returned by display are not reliable for some models e.g. 2.1" displays return "chs_5inch"
+        # Rely on width/height for sub-revision detection instead
+        if self.display_width == 480 and self.display_height == 480:
+            self.sub_revision = SubRevision.REV_2INCH
+        elif self.display_width == 480 and self.display_height == 800:
+            self.sub_revision = SubRevision.REV_5INCH
+        elif self.display_width == 480 and self.display_height == 1920:
+            self.sub_revision = SubRevision.REV_8INCH
+        else:
+            self.sub_revision = SubRevision.UNKNOWN
+            logger.error(f"Unsupported resolution {self.display_width}x{self.display_height} for revision C")
+
         self.openSerial()
 
     def __del__(self):
@@ -214,7 +229,6 @@ def _send_command(self, cmd: Command, payload: Optional[bytearray] = None, paddi
 
     def _hello(self):
         # This command reads LCD answer on serial link, so it bypasses the queue
-        self.sub_revision = SubRevision.UNKNOWN
         self.serial_flush_input()
         self._send_command(Command.HELLO, bypass_queue=True)
         response = ''.join(
@@ -230,17 +244,6 @@ def _hello(self):
             self.serial_flush_input()
             logger.debug("Display ID returned: %s" % response)
 
-        # Note: ID returned by display are not reliable for some models e.g. 2.1" displays return "chs_5inch"
-        # Rely on width/height for sub-revision detection
-        if self.display_width == 480 and self.display_height == 480:
-            self.sub_revision = SubRevision.REV_2INCH
-        elif self.display_width == 480 and self.display_height == 800:
-            self.sub_revision = SubRevision.REV_5INCH
-        elif self.display_width == 480 and self.display_height == 1920:
-            self.sub_revision = SubRevision.REV_8INCH
-        else:
-            logger.error(f"Unsupported resolution {self.display_width}x{self.display_height} for revision C")
-
         # Detect ROM version
         try:
             self.rom_version = int(response.split(".")[2])