Implement get/set_lpmode API for SFF8472 (#512)

* Add get/set_lpmode API for SFF8472

The lpmode is not supported by SFF8472

* Add unittest for get/set_lpmode for SFF8472

---------

Co-authored-by: Andy Wong <andywong@arista.com>

sonic_platform_base/sonic_xcvr/api/public/sff8472.py

@@ -37,7 +37,7 @@ def get_transceiver_info(self):
             if len > 0:
                 cable_len = len
                 cable_type = type
- 
+
         xcvr_info = {
             "type": serial_id[consts.ID_FIELD],
             "type_abbrv_name": serial_id[consts.ID_ABBRV_FIELD],
@@ -296,5 +296,26 @@ def get_lpmode_support(self):
     def get_power_override_support(self):
         return False
 
+    def get_lpmode(self):
+        '''
+        Retrieves low power mode status
+
+        Returns:
+            bool: True if module in low power else returns False.
+        '''
+        return False
+
+    def set_lpmode(self, lpmode):
+        '''
+        This function sets LPMode for the module.
+
+        Args:
+            lpmode (bool): False means LPMode Off, True means LPMode On
+
+        Returns:
+            bool: True if the provision succeeds, False if it fails
+        '''
+        return False
+
     def is_copper(self):
         return self.xcvr_eeprom.read(consts.SFP_CABLE_TECH_FIELD) == 'Passive Cable'

tests/sonic_xcvr/test_sff8472.py

@@ -290,3 +290,9 @@ def test_get_transceiver_bulk_status(self, mock_response, expected):
         result = self.api.get_transceiver_bulk_status()
         assert result == expected
 
+    def test_get_lpmode(self):
+        assert not self.api.get_lpmode()
+
+    def test_set_lpmode(self):
+        assert not self.api.set_lpmode(True)
+        assert not self.api.set_lpmode(False)