[socket] Remove legacy aliases, fix NETCONN count, add comments

- Remove SOCKET_TCP/SOCKET_UDP aliases, use SocketType.UDP everywhere
- Fix MEMP_NUM_NETCONN to include listening_tcp (listeners need netconns)
- Add comment on listening_tcp minimum (not all components register yet)
- Add comment on MAX_LISTENING_SOCKETS_TCP (BK-specific, RTL/LN use
  MEMP_NUM_TCP_PCB_LISTEN directly)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

esphome/components/libretiny/__init__.py

@@ -326,7 +326,8 @@ def _configure_lwip(config: dict) -> None:
     tcp_sockets = max(MIN_TCP_SOCKETS, raw_tcp)
     udp_sockets = max(MIN_UDP_SOCKETS, raw_udp)
     # Listening sockets — registered by components (api, ota, web_server_base, etc.)
-    listening_tcp = max(raw_tcp_listen, 2)  # at least 2 (api + ota)
+    # Not all components register yet, so ensure a minimum of 2 (api + ota baseline).
+    listening_tcp = max(raw_tcp_listen, 2)
 
     # TCP_SND_BUF: ESPAsyncWebServer allocates malloc(tcp_sndbuf()) per
     # response chunk. At 10×MSS=14.6KB (BK default) this causes OOM (#14095).
@@ -356,7 +357,8 @@ def _configure_lwip(config: dict) -> None:
         # Socket counts — auto-calculated from component registrations
         f"MAX_SOCKETS_TCP={tcp_sockets}",
         f"MAX_SOCKETS_UDP={udp_sockets}",
-        # Listening sockets — auto-calculated from component registrations
+        # Listening sockets — BK SDK uses this to derive MEMP_NUM_TCP_PCB_LISTEN;
+        # RTL/LN don't use it, but we set MEMP_NUM_TCP_PCB_LISTEN explicitly below.
         f"MAX_LISTENING_SOCKETS_TCP={listening_tcp}",
         # Queued segment limits — derived from 4×MSS buffer size
         f"TCP_SND_QUEUELEN={tcp_snd_queuelen}",
@@ -366,8 +368,8 @@ def _configure_lwip(config: dict) -> None:
         f"MEMP_NUM_TCP_PCB_LISTEN={listening_tcp}",  # BK: =MAX_LISTENING, RTL: 5, LN: 3
         # UDP PCB pool — includes wifi.lwip_internal (DHCP + DNS)
         f"MEMP_NUM_UDP_PCB={udp_sockets}",  # BK: 25, RTL/LN: 7 via LT
-        # Netconn pool — listening sockets are already counted in tcp_sockets
-        f"MEMP_NUM_NETCONN={tcp_sockets + udp_sockets}",
+        # Netconn pool — each socket (active + listening) needs a netconn
+        f"MEMP_NUM_NETCONN={tcp_sockets + udp_sockets + listening_tcp}",
         # Netbuf pool
         "MEMP_NUM_NETBUF=4",  # BK: 16, RTL: 2 (opt.h), LN: 8
         # Inbound message pool

esphome/components/mdns/__init__.py

@@ -56,7 +56,7 @@ def _consume_mdns_sockets(config: ConfigType) -> ConfigType:
     from esphome.components import socket
 
     # mDNS needs 2 sockets (IPv4 + IPv6 multicast)
-    socket.consume_sockets(2, "mdns", socket.SOCKET_UDP)(config)
+    socket.consume_sockets(2, "mdns", socket.SocketType.UDP)(config)
     return config
 
 

esphome/components/socket/__init__.py

@@ -38,10 +38,6 @@ class SocketType(StrEnum):
     TCP_LISTEN = "tcp_listen"
 
 
-# Legacy aliases
-SOCKET_TCP = SocketType.TCP
-SOCKET_UDP = SocketType.UDP
-
 _SOCKET_TYPE_KEYS = {
     SocketType.TCP: KEY_SOCKET_CONSUMERS_TCP,
     SocketType.UDP: KEY_SOCKET_CONSUMERS_UDP,
@@ -134,7 +130,7 @@ def require_wake_loop_threadsafe() -> None:
         CORE.data[KEY_WAKE_LOOP_THREADSAFE_REQUIRED] = True
         cg.add_define("USE_WAKE_LOOP_THREADSAFE")
         # Consume 1 socket for the shared wake notification socket
-        consume_sockets(1, "socket.wake_loop_threadsafe", SOCKET_UDP)({})
+        consume_sockets(1, "socket.wake_loop_threadsafe", SocketType.UDP)({})
 
 
 CONFIG_SCHEMA = cv.Schema(

esphome/components/udp/__init__.py

@@ -73,7 +73,7 @@ def _consume_udp_sockets(config: ConfigType) -> ConfigType:
 
     # UDP uses up to 2 sockets: 1 broadcast + 1 listen
     # Whether each is used depends on code generation, so register worst case
-    socket.consume_sockets(2, "udp", socket.SOCKET_UDP)(config)
+    socket.consume_sockets(2, "udp", socket.SocketType.UDP)(config)
     return config
 
 

esphome/components/wifi/__init__.py

@@ -284,7 +284,7 @@ def _consume_wifi_sockets(config: ConfigType) -> ConfigType:
 
     # lwIP allocates UDP PCBs for DHCP client and DNS resolver internally.
     # These are not application sockets but consume MEMP_NUM_UDP_PCB pool entries.
-    socket.consume_sockets(2, "wifi.lwip_internal", socket.SOCKET_UDP)(config)
+    socket.consume_sockets(2, "wifi.lwip_internal", socket.SocketType.UDP)(config)
     return config