[Smartswitch][chassisd] Addition of pre shutdown and post startup function calls (#619)

The pre shutdown and post startup functions are called on DPU admin state change operations

Author: gpunathilell

sonic-chassisd/scripts/chassisd

@@ -247,7 +247,15 @@ class SmartSwitchModuleConfigUpdater(logger.Logger):
             self.log_warning("Invalid admin_state value: {}".format(admin_state))
 
     def submit_callback(self, module_index, admin_state):
+        if admin_state == MODULE_ADMIN_DOWN:
+            # This is only valid on platforms which have pci_detach and sensord changes required. If it is not implemented,
+            # there are no actions taken during this function execution.
+            try_get(self.chassis.get_module(module_index).module_pre_shutdown, default=False)
         try_get(self.chassis.get_module(module_index).set_admin_state, admin_state, default=False)
+        if admin_state == MODULE_ADMIN_UP:
+            # This is only valid on platforms which have pci_rescan sensord changes required. If it is not implemented,
+            # there are no actions taken during this function execution.
+            try_get(self.chassis.get_module(module_index).module_post_startup, default=False)
         pass
 
 #

sonic-chassisd/tests/mock_platform.py

@@ -72,6 +72,12 @@ def set_midplane_ip(self):
         else:
             self.midplane_ip = '192.168.1.{}'.format(self.get_slot())
 
+    def module_pre_shutdown(self):
+        pass
+
+    def module_post_startup(self):
+        pass
+
     def is_midplane_reachable(self):
         return self.midplane_access
 

sonic-chassisd/tests/test_chassisd.py

@@ -523,13 +523,22 @@ def test_smartswitch_configupdater_check_admin_state():
     chassis.module_list.append(module)
 
     config_updater = SmartSwitchModuleConfigUpdater(SYSLOG_IDENTIFIER, chassis)
+
+    # Test setting admin state to down
     admin_state = 0
-    config_updater.module_config_update(name, admin_state)
-    assert module.get_admin_state() == admin_state
+    with patch.object(module, 'module_pre_shutdown') as mock_module_pre_shutdown, \
+         patch.object(module, 'set_admin_state') as mock_set_admin_state:
+        config_updater.module_config_update(name, admin_state)
+        mock_module_pre_shutdown.assert_called_once()
+        mock_set_admin_state.assert_called_once_with(admin_state)
 
+    # Test setting admin state to up
     admin_state = 1
-    config_updater.module_config_update(name, admin_state)
-    assert module.get_admin_state() == admin_state
+    with patch.object(module, 'set_admin_state') as mock_set_admin_state, \
+         patch.object(module, 'module_post_startup') as mock_module_post_startup:
+        config_updater.module_config_update(name, admin_state)
+        mock_set_admin_state.assert_called_once_with(admin_state)
+        mock_module_post_startup.assert_called_once()
 
 
     @patch("your_module.glob.glob")