[wifi] Skip the post-connect roam scan on LN882x by default

esphome/components/wifi/__init__.py

@@ -542,7 +542,18 @@ CONFIG_SCHEMA = cv.All(
             ),
             cv.Optional(CONF_PASSIVE_SCAN, default=False): cv.boolean,
             cv.Optional(CONF_ENABLE_ON_BOOT, default=True): cv.boolean,
-            cv.Optional(CONF_POST_CONNECT_ROAMING, default=True): cv.boolean,
+            # An LN882H scan takes the radio off the AP long enough to drop
+            # the association, so the post-connect roam check costs a
+            # disconnect there.
+            cv.SplitDefault(
+                CONF_POST_CONNECT_ROAMING,
+                esp8266=True,
+                esp32=True,
+                rp2=True,
+                bk72xx=True,
+                rtl87xx=True,
+                ln882x=False,
+            ): cv.boolean,
             cv.Optional(CONF_ON_CONNECT): automation.validate_automation(single=True),
             cv.Optional(CONF_ON_DISCONNECT): automation.validate_automation(
                 single=True

tests/component_tests/wifi/config/bare_ln882x.yaml

@@ -0,0 +1,12 @@
+---
+esphome:
+  name: test
+
+ln882x:
+  board: generic-ln882h
+
+wifi:
+  ssid: test
+  password: testtest
+  ap:
+    ssid: fallback

tests/component_tests/wifi/test_default_setters.py

@@ -37,3 +37,13 @@ def test_custom_values_are_emitted(
     assert "set_reboot_timeout(0);" in main_cpp
     assert "set_power_save_mode(wifi::WIFI_POWER_SAVE_LIGHT);" in main_cpp
     assert "set_min_auth_mode(wifi::WIFI_MIN_AUTH_MODE_WPA);" in main_cpp
+
+
+def test_ln882x_skips_post_connect_roaming(
+    generate_main: Callable[[str | Path], str],
+    component_config_path: Callable[[str], Path],
+) -> None:
+    """An LN882H scan drops the association, so LN882x does not roam by default."""
+    main_cpp = generate_main(component_config_path("bare_ln882x.yaml"))
+
+    assert "set_post_connect_roaming(false);" in main_cpp