Fix GCU update speed case to use supported speed get from the dut

tests/generic_config_updater/test_eth_interface.py

@@ -2,6 +2,7 @@
 import logging
 import pytest
 import re
+import random
 
 from tests.common.helpers.assertions import pytest_assert
 from tests.generic_config_updater.gu_utils import apply_patch, expect_op_success, expect_op_failure
@@ -10,7 +11,6 @@
 
 logger = logging.getLogger(__name__)
 
-
 @pytest.fixture(autouse=True)
 def ensure_dut_readiness(duthost):
     """
@@ -75,6 +75,24 @@ def get_ethernet_port_not_in_portchannel(duthost):
             break
     return port_name
 
+def get_port_speeds_for_test(duthost):
+    """
+    Get the speeds parameters for case test_update_speed, including 2 valid speeds and 1 invalid speed
+
+    Args:
+        duthost: DUT host object
+    """
+    speeds_to_test = []
+    invalid_speed = ("20a", False)
+    if duthost.get_facts()['asic_type'] == 'vs':
+        valid_speeds = ['20000', '40000']
+    else:
+        valid_speeds = duthost.get_supported_speeds('Ethernet0')
+    pytest_assert(valid_speeds, "Failed to get any valid port speed to test.")
+    valid_speeds_to_test = random.sample(valid_speeds, 2 if len(valid_speeds) >= 2 else len(valid_speeds))
+    speeds_to_test = [(speed, True) for speed in valid_speeds_to_test]
+    speeds_to_test.append(invalid_speed)
+    return speeds_to_test
 
 def test_remove_lanes(duthost, ensure_dut_readiness):
     json_patch = [
@@ -214,33 +232,30 @@ def test_update_valid_invalid_index(duthost, ensure_dut_readiness, index, is_val
         delete_tmpfile(duthost, tmpfile)
 
 
-@pytest.mark.parametrize("speed, is_valid", [
-    ("20000", True),
-    ("40000", True),
-    ("20a", False)
-])
-def test_update_speed(duthost, ensure_dut_readiness, speed, is_valid):
-    json_patch = [
-        {
-            "op": "replace",
-            "path": "/PORT/Ethernet0/speed",
-            "value": "{}".format(speed)
-        }
-    ]
-
-    tmpfile = generate_tmpfile(duthost)
-    logger.info("tmpfile {}".format(tmpfile))
-
-    try:
-        output = apply_patch(duthost, json_data=json_patch, dest_file=tmpfile)
-        if is_valid:
-            expect_op_success(duthost, output)
-            current_status_speed = check_interface_status(duthost, "Speed").replace("G", "000")
-            pytest_assert(current_status_speed == speed, "Failed to properly configure interface speed to requested value {}".format(speed))
-        else:
-            expect_op_failure(output)
-    finally:
-        delete_tmpfile(duthost, tmpfile)
+def test_update_speed(duthost, ensure_dut_readiness):
+    speed_params = get_port_speeds_for_test(duthost)
+    for speed, is_valid in speed_params:
+        json_patch = [
+            {
+                "op": "replace",
+                "path": "/PORT/Ethernet0/speed",
+                "value": "{}".format(speed)
+            }
+        ]
+
+        tmpfile = generate_tmpfile(duthost)
+        logger.info("tmpfile {}".format(tmpfile))
+
+        try:
+            output = apply_patch(duthost, json_data=json_patch, dest_file=tmpfile)
+            if is_valid:
+                expect_op_success(duthost, output)
+                current_status_speed = check_interface_status(duthost, "Speed").replace("G", "000")
+                pytest_assert(current_status_speed == speed, "Failed to properly configure interface speed to requested value {}".format(speed))
+            else:
+                expect_op_failure(output)
+        finally:
+            delete_tmpfile(duthost, tmpfile)
 
 
 def test_update_description(duthost, ensure_dut_readiness):