Merge remote-tracking branch 'origin/dev' into api-reverse-connection

Co-authored-by: puddly <32534428+puddly@users.noreply.github.com>

.github/workflows/stale.yml

@@ -33,7 +33,7 @@ jobs:
         and will be closed if no further activity occurs within 7 days.
 
         If you are the author of this PR, please leave a comment if you want
-        to keep it open. Also, please rebase your PR onto the latest dev
+        to keep it open. Also, please merge the latest dev branch into your
         branch to ensure that it's up to date with the latest changes.
 
         Thank you for your contribution!

esphome/components/api/__init__.py

@@ -5,7 +5,7 @@ from typing import Any
 from esphome import automation
 from esphome.automation import Condition
 import esphome.codegen as cg
-from esphome.components.const import CONF_DESCRIPTION
+from esphome.components.const import CONF_DESCRIPTION, CONF_HOST
 from esphome.components.logger import request_log_listener
 
 # ENCRYPTION_SCHEMA and validate_encryption_key are re-exported for external
@@ -25,6 +25,8 @@ from esphome.const import (
     CONF_CAPTURE_RESPONSE,
     CONF_DATA,
     CONF_DATA_TEMPLATE,
+    CONF_DELAY,
+    CONF_ENABLE_IPV6,
     CONF_ENCRYPTION,
     CONF_EVENT,
     CONF_ID,
@@ -48,6 +50,7 @@ from esphome.const import (
 )
 from esphome.core import CORE, ID, CoroPriority, EsphomeError, coroutine_with_priority
 from esphome.cpp_generator import MockObj, TemplateArgsType
+import esphome.final_validate as fv
 from esphome.helpers import fnv1_hash
 from esphome.types import ConfigFragmentType, ConfigType
 
@@ -134,6 +137,7 @@ CONF_HOMEASSISTANT_SERVICES = "homeassistant_services"
 CONF_HOMEASSISTANT_STATES = "homeassistant_states"
 CONF_LISTEN_BACKLOG = "listen_backlog"
 CONF_MAX_SEND_QUEUE = "max_send_queue"
+CONF_OUTGOING_CONNECTION = "outgoing_connection"
 CONF_STATE_SUBSCRIPTION_ONLY = "state_subscription_only"
 
 
@@ -285,9 +289,44 @@ def _consume_api_sockets(config: ConfigType) -> ConfigType:
     # (not max_connections, which is the upper limit rarely reached)
     socket.consume_sockets(3, "api")(config)
     socket.consume_sockets(1, "api", socket.SocketType.TCP_LISTEN)(config)
+    if CONF_OUTGOING_CONNECTION in config:
+        socket.consume_sockets(1, "api_outgoing_connection")(config)
     return config
 
 
+def _validate_outgoing_connection(config: ConfigType) -> ConfigType:
+    if CONF_OUTGOING_CONNECTION not in config:
+        return config
+    if CONF_ENCRYPTION not in config:
+        raise cv.Invalid(
+            "outgoing_connection requires 'encryption' so the peer is verified by key",
+            path=[CONF_OUTGOING_CONNECTION],
+        )
+    return config
+
+
+_OUTGOING_CONNECTION_SCHEMA = cv.Schema(
+    {
+        cv.Optional(CONF_HOST): cv.ipaddress,
+        cv.Optional(CONF_PORT, default=6054): cv.port,
+        # Bounded to half the device's uint32 millisecond range so the wait
+        # always elapses under a wrapping clock
+        cv.Optional(CONF_DELAY, default="60s"): cv.All(
+            cv.positive_time_period_milliseconds,
+            cv.Range(max=cv.TimePeriod(milliseconds=2147483647)),
+        ),
+    }
+)
+
+
+def _outgoing_connection_schema(config: ConfigType | None) -> ConfigType:
+    # A bare `outgoing_connection:` block is valid; without a host the device
+    # dials the remembered last dial-back client
+    if config is None:
+        config = {}
+    return _OUTGOING_CONNECTION_SCHEMA(config)
+
+
 CONFIG_SCHEMA = cv.All(
     cv.Schema(
         {
@@ -312,6 +351,7 @@ CONFIG_SCHEMA = cv.All(
             ): ACTIONS_SCHEMA,
             cv.Exclusive(CONF_ACTIONS, group_of_exclusion=CONF_ACTIONS): ACTIONS_SCHEMA,
             cv.Optional(CONF_ENCRYPTION): encryption_schema,
+            cv.Optional(CONF_OUTGOING_CONNECTION): _outgoing_connection_schema,
             cv.Optional(CONF_BATCH_DELAY, default="100ms"): cv.All(
                 cv.positive_time_period_milliseconds,
                 cv.Range(max=cv.TimePeriod(milliseconds=65535)),
@@ -368,6 +408,7 @@ CONFIG_SCHEMA = cv.All(
         }
     ).extend(cv.COMPONENT_SCHEMA),
     cv.rename_key(CONF_SERVICES, CONF_ACTIONS),
+    _validate_outgoing_connection,
     _consume_api_sockets,
     _register_provisioning_source,
 )
@@ -424,7 +465,52 @@ def _validate_esp8266_action_strings(config: ConfigType) -> ConfigType:
     return config
 
 
-FINAL_VALIDATE_SCHEMA = _validate_esp8266_action_strings
+def _validate_outgoing_socket_implementation(config: ConfigType) -> ConfigType:
+    """Reject the raw lwip_tcp socket, the only option on ESP8266 and RP2040.
+
+    Checked against the resolved implementation so an explicit selection on
+    another platform is caught the same way as the platform default.
+    """
+    if CONF_OUTGOING_CONNECTION not in config:
+        return config
+    from esphome.components import socket
+
+    socket_conf = fv.full_config.get().get("socket") or {}
+    if (
+        impl := socket_conf.get(socket.CONF_IMPLEMENTATION)
+    ) in socket.IMPLEMENTATIONS_WITHOUT_CONNECT:
+        raise cv.Invalid(
+            f"outgoing_connection is not supported with the {impl} socket "
+            "implementation (the only one on ESP8266 and RP2040) because it "
+            "cannot make outgoing connections",
+            path=[CONF_OUTGOING_CONNECTION],
+        )
+    return config
+
+
+def _validate_outgoing_host_ipv6(config: ConfigType) -> ConfigType:
+    """An IPv6 host can never be parsed, so never dialed, without IPv6."""
+    if (
+        (outgoing := config.get(CONF_OUTGOING_CONNECTION)) is None
+        or (host := outgoing.get(CONF_HOST)) is None
+        or host.version != 6
+    ):
+        return config
+    network_conf = fv.full_config.get().get("network") or {}
+    if not network_conf.get(CONF_ENABLE_IPV6):
+        raise cv.Invalid(
+            "outgoing_connection host is an IPv6 address but IPv6 is not "
+            "enabled; set 'network: enable_ipv6: true'",
+            path=[CONF_OUTGOING_CONNECTION, CONF_HOST],
+        )
+    return config
+
+
+FINAL_VALIDATE_SCHEMA = cv.All(
+    _validate_esp8266_action_strings,
+    _validate_outgoing_socket_implementation,
+    _validate_outgoing_host_ipv6,
+)
 
 
 def _add_action_strings(
@@ -606,6 +692,13 @@ async def to_code(config: ConfigType) -> None:
     else:
         cg.add_define("USE_API_PLAINTEXT")
 
+    if (outgoing := config.get(CONF_OUTGOING_CONNECTION)) is not None:
+        cg.add_define("USE_API_OUTGOING_CONNECTION")
+        if (host := outgoing.get(CONF_HOST)) is not None:
+            cg.add_define("API_OUTGOING_CONNECTION_HOST", str(host))
+        cg.add_define("API_OUTGOING_CONNECTION_PORT", outgoing[CONF_PORT])
+        cg.add_define("API_OUTGOING_CONNECTION_DELAY", outgoing[CONF_DELAY])
+
     cg.add_define("USE_API")
     cg.add_global(api_ns.using)
 
@@ -992,6 +1085,7 @@ _define_filter = filter_source_files_from_defines(
         "user_services.cpp": "USE_API_USER_DEFINED_ACTIONS",
         "api_frame_helper_noise.cpp": "USE_API_NOISE",
         "api_frame_helper_plaintext.cpp": "USE_API_PLAINTEXT",
+        "api_outgoing_connection.cpp": "USE_API_OUTGOING_CONNECTION",
     }
 )
 

esphome/components/api/api.proto

@@ -77,6 +77,7 @@ service APIConnection {
   rpc serial_proxy_set_modem_pins(SerialProxySetModemPinsRequest) returns (void) {}
   rpc serial_proxy_get_modem_pins(SerialProxyGetModemPinsRequest) returns (void) {}
   rpc serial_proxy_request(SerialProxyRequest) returns (void) {}
+  rpc serial_proxy_set_mode(SerialProxySetModeRequest) returns (void) {}
 }
 
 
@@ -112,6 +113,11 @@ message HelloRequest {
   string client_info = 1;
   uint32 api_version_major = 2;
   uint32 api_version_minor = 3;
+
+  // Set by clients that can accept connections the device opens to them
+  // (see api: outgoing_connection:). The device remembers this client's
+  // address as the target to dial when no such client is connected.
+  bool outgoing_connection_target = 4 [(field_ifdef) = "USE_API_OUTGOING_CONNECTION"];
 }
 
 // Confirmation of successful connection request.
@@ -331,6 +337,10 @@ message DeviceInfoResponse {
   // all-zeros PSK, so the api encryption key can be provisioned without being
   // sent in plaintext (protects against passive sniffing, not active MITM)
   bool api_encryption_provisionable = 26 [(field_ifdef) = "USE_API_NOISE"];
+
+  // Device is built with the api outgoing_connection option and can open
+  // the TCP connection to a dial-back target itself
+  bool api_outgoing_connection_supported = 27 [(field_ifdef) = "USE_API_OUTGOING_CONNECTION"];
 }
 
 // ==================== DEVICE CAPABILITIES ====================
@@ -2726,7 +2736,8 @@ enum SerialProxyParity {
   SERIAL_PROXY_PARITY_ODD = 2;
 }
 
-// Configure UART parameters for a serial proxy instance
+// Configure UART parameters for a serial proxy instance. Only the subscribed client may
+// configure the port; others are refused with PORT_IN_USE (since API 1.17).
 message SerialProxyConfigureRequest {
   option (id) = 138;
   option (source) = SOURCE_CLIENT;
@@ -2752,7 +2763,8 @@ message SerialProxyDataReceived {
   bytes data = 2;               // Raw data received from the serial device
 }
 
-// Write data to a serial device
+// Write data to a serial device. Only the subscribed client may write; writes from
+// others are ignored (since API 1.17).
 message SerialProxyWriteRequest {
   option (id) = 140;
   option (source) = SOURCE_CLIENT;
@@ -2763,7 +2775,8 @@ message SerialProxyWriteRequest {
   bytes data = 2;               // Raw data to write to the serial device
 }
 
-// Set modem control pin states (RTS and DTR)
+// Set modem control pin states (RTS and DTR). Only the subscribed client may set them;
+// others are refused with PORT_IN_USE (since API 1.17).
 message SerialProxySetModemPinsRequest {
   option (id) = 141;
   option (source) = SOURCE_CLIENT;
@@ -2802,6 +2815,7 @@ enum SerialProxyRequestType {
   // error the device answers with INVALID_ARGUMENT.
   SERIAL_PROXY_REQUEST_TYPE_CONFIGURE = 3;      // Acknowledges a SerialProxyConfigureRequest
   SERIAL_PROXY_REQUEST_TYPE_SET_MODEM_PINS = 4; // Acknowledges a SerialProxySetModemPinsRequest
+  SERIAL_PROXY_REQUEST_TYPE_SET_MODE = 5;       // Acknowledges a SerialProxySetModeRequest (since API 1.17)
 }
 
 enum SerialProxyStatus {
@@ -2814,7 +2828,8 @@ enum SerialProxyStatus {
   SERIAL_PROXY_STATUS_INVALID_ARGUMENT = 6; // Invalid instance index or parameter value
 }
 
-// Generic request message for simple serial proxy operations
+// Generic request message for simple serial proxy operations. FLUSH requires an active
+// subscription; it is refused with PORT_IN_USE otherwise (since API 1.17).
 message SerialProxyRequest {
   option (id) = 144;
   option (source) = SOURCE_CLIENT;
@@ -2838,6 +2853,29 @@ message SerialProxyRequestResponse {
   string error_message = 4;            // Additional detail on failure (optional)
 }
 
+// How a port treats the bytes passing through it. RAW is a plain byte pipe; PROTOCOL
+// activates the port's protocol-aware tap (if one is configured), letting it observe
+// traffic and inject protocol bytes such as acknowledgements. Which protocol the tap
+// speaks is a property of the device configuration, discoverable from the tap
+// component's own API surface. A client that is about to flash firmware selects RAW
+// first, which definitively disables that injection.
+enum SerialProxyMode {
+  SERIAL_PROXY_MODE_RAW = 0;
+  SERIAL_PROXY_MODE_PROTOCOL = 1;
+}
+
+// Only the subscribed client may change the mode; any other caller -- including one that
+// never subscribed -- is refused with PORT_IN_USE. PROTOCOL is refused with NOT_SUPPORTED
+// when the port has no protocol-aware tap configured.
+message SerialProxySetModeRequest {
+  option (id) = 152;
+  option (source) = SOURCE_CLIENT;
+  option (ifdef) = "USE_SERIAL_PROXY";
+
+  uint32 instance = 1;
+  SerialProxyMode mode = 2;
+}
+
 // ==================== BLUETOOTH CONNECTION PARAMS ====================
 message BluetoothSetConnectionParamsRequest {
   option (id) = 145;

esphome/components/api/api_connection.cpp

@@ -1661,6 +1661,7 @@ void APIConnection::on_serial_proxy_request(const SerialProxyRequest &msg) {
       break;
     case enums::SERIAL_PROXY_REQUEST_TYPE_CONFIGURE:
     case enums::SERIAL_PROXY_REQUEST_TYPE_SET_MODEM_PINS:
+    case enums::SERIAL_PROXY_REQUEST_TYPE_SET_MODE:
       // Response-only discriminators; never valid in a request
       ESP_LOGW(TAG, "Response-only serial proxy request type: %" PRIu32, static_cast<uint32_t>(msg.type));
       status = enums::SERIAL_PROXY_STATUS_INVALID_ARGUMENT;
@@ -1673,6 +1674,19 @@ void APIConnection::on_serial_proxy_request(const SerialProxyRequest &msg) {
   send_serial_proxy_ack(this, msg.instance, msg.type, status);
 }
 
+void APIConnection::on_serial_proxy_set_mode_request(const SerialProxySetModeRequest &msg) {
+  auto &proxies = App.get_serial_proxies();
+  if (msg.instance >= proxies.size()) {
+    ESP_LOGW(TAG, "Serial proxy instance %" PRIu32 " out of range", msg.instance);
+    send_serial_proxy_ack(this, msg.instance, enums::SERIAL_PROXY_REQUEST_TYPE_SET_MODE,
+                          enums::SERIAL_PROXY_STATUS_INVALID_ARGUMENT);
+    return;
+  }
+  serial_proxy::SerialProxyResult result = proxies[msg.instance]->set_mode_from_client(this, msg.mode);
+  send_serial_proxy_ack(this, msg.instance, enums::SERIAL_PROXY_REQUEST_TYPE_SET_MODE,
+                        serial_proxy_result_to_status(result));
+}
+
 void APIConnection::send_serial_proxy_data(const SerialProxyDataReceived &msg) {
   if (!this->send_message(msg)) {
     ESP_LOGV(TAG, "Serial proxy data dropped, TCP buffer full");
@@ -1799,7 +1813,7 @@ bool APIConnection::send_hello_response_(const HelloRequest &msg) {
 
   HelloResponse resp;
   resp.api_version_major = 1;
-  resp.api_version_minor = 16;
+  resp.api_version_minor = 17;
   // Send only the version string - the client only logs this for debugging and doesn't use it otherwise
   resp.server_info = ESPHOME_VERSION_REF;
   resp.name = StringRef(App.get_name());
@@ -1822,6 +1836,19 @@ bool APIConnection::send_hello_response_(const HelloRequest &msg) {
   // Auto-authenticate - password auth was removed in ESPHome 2026.1.0
   this->complete_authentication_();
 
+#ifdef USE_API_OUTGOING_CONNECTION
+  // With a PSK set only key-verified transports reach hello: plaintext and
+  // zero-PSK are rejected, and pre-activation sessions are force-closed
+  if (msg.outgoing_connection_target && !this->flags_.outgoing_connection_target) {
+    if (this->parent_->get_noise_ctx().has_psk()) {
+      this->flags_.outgoing_connection_target = true;
+      this->parent_->on_outgoing_target_client(this);
+    } else {
+      this->log_client_(ESPHOME_LOG_LEVEL_WARN, LOG_STR("Dial-back target refused; no key active"));
+    }
+  }
+#endif
+
   return this->send_message(resp);
 }
 
@@ -1944,6 +1971,9 @@ bool APIConnection::send_device_info_response_() {
   // one) so this advertisement survives the plaintext removal in 2027.2.0.
   resp.api_encryption_provisionable = !this->parent_->get_noise_ctx().has_psk();
 #endif
+#ifdef USE_API_OUTGOING_CONNECTION
+  resp.api_outgoing_connection_supported = true;
+#endif
 #endif
 #ifdef USE_DEVICES
   size_t device_index = 0;

esphome/components/api/api_connection.h

@@ -244,6 +244,7 @@ class APIConnection final : public APIServerConnectionBase {
   void on_serial_proxy_set_modem_pins_request(const SerialProxySetModemPinsRequest &msg);
   void on_serial_proxy_get_modem_pins_request(const SerialProxyGetModemPinsRequest &msg);
   void on_serial_proxy_request(const SerialProxyRequest &msg);
+  void on_serial_proxy_set_mode_request(const SerialProxySetModeRequest &msg);
   void send_serial_proxy_data(const SerialProxyDataReceived &msg);
 #endif
 
@@ -375,6 +376,21 @@ class APIConnection final : public APIServerConnectionBase {
     return this->helper_->get_peername_to(buf);
   }
 
+#ifdef USE_API_OUTGOING_CONNECTION
+  /// Outgoing connection: send our server hello immediately so the peer can
+  /// pick the matching key. Outgoing connections are only dialed when a PSK
+  /// is set, so the helper is always the noise helper. Call after start().
+  void mark_outgoing() {
+    if (this->flags_.remove) {
+      return;  // start() failed; the connection is already being torn down
+    }
+    APIError err = static_cast<APINoiseFrameHelper *>(this->helper_.get())->send_server_hello_first();
+    if (err != APIError::OK) {
+      this->fatal_error_with_log_(LOG_STR("Server hello failed"), err);
+    }
+  }
+#endif
+
  protected:
   bool try_to_clear_buffer_slow_(bool log_out_of_space);
 
@@ -745,6 +761,9 @@ class APIConnection final : public APIServerConnectionBase {
     uint8_t batch_first_message : 1;          // For batch buffer allocation
     uint8_t should_try_send_immediately : 1;  // True after initial states are sent
     uint8_t may_have_remaining_data : 1;      // Read loop hit limit, retry without ready check
+#ifdef USE_API_OUTGOING_CONNECTION
+    uint8_t outgoing_connection_target : 1;  // Client declared itself a dial-back target in its hello
+#endif
 #ifdef HAS_PROTO_MESSAGE_DUMP
     uint8_t log_only_mode : 1;
 #endif

esphome/components/api/api_frame_helper.h

@@ -282,7 +282,8 @@ class APIFrameHelper {
     DATA = 5,
     CLOSED = 6,
     FAILED = 7,
-    EXPLICIT_REJECT = 8,  // Noise only
+    EXPLICIT_REJECT = 8,        // Noise only
+    CLIENT_HELLO_OUTGOING = 9,  // Noise only: like CLIENT_HELLO but the server hello already went out (outgoing conn)
   };
 
   // Fast inline state check for read_packet/write_protobuf_messages hot path.

esphome/components/api/api_frame_helper_noise.cpp

@@ -81,6 +81,13 @@ APIError APINoiseFrameHelper::init() {
   state_ = State::CLIENT_HELLO;
   return APIError::OK;
 }
+#ifdef USE_API_OUTGOING_CONNECTION
+APIError APINoiseFrameHelper::send_server_hello_first() {
+  // The peer needs our name and MAC to pick the key before its first message
+  this->state_ = State::CLIENT_HELLO_OUTGOING;
+  return this->send_server_hello_frame_();
+}
+#endif
 #ifdef USE_API_PLAINTEXT
 APIError APINoiseFrameHelper::init_from_handoff(const uint8_t *header, uint8_t header_len) {
   APIError err = this->init();
@@ -253,6 +260,9 @@ APIError APINoiseFrameHelper::state_action_() {
       HELPER_LOG("Bad state for method: %d", (int) this->state_);
       return APIError::BAD_STATE;
     case State::CLIENT_HELLO:
+#ifdef USE_API_OUTGOING_CONNECTION
+    case State::CLIENT_HELLO_OUTGOING:
+#endif
       return this->state_action_client_hello_();
     case State::SERVER_HELLO:
       return this->state_action_server_hello_();
@@ -285,11 +295,16 @@ APIError APINoiseFrameHelper::state_action_client_hello_() {
     std::memcpy(this->prologue_.data() + old_size + 2, this->rx_buf_.data(), rx_size);
   }
 
+#ifdef USE_API_OUTGOING_CONNECTION
+  if (this->state_ == State::CLIENT_HELLO_OUTGOING) {
+    // Server hello already went out at handoff
+    return this->start_handshake_();
+  }
+#endif
   state_ = State::SERVER_HELLO;
   return APIError::OK;
 }
-APIError APINoiseFrameHelper::state_action_server_hello_() {
-  // send server hello
+APIError APINoiseFrameHelper::send_server_hello_frame_() {
   const auto &name = App.get_name();
   char mac[MAC_ADDRESS_BUFFER_SIZE];
   get_mac_address_into_buffer(mac);
@@ -313,15 +328,18 @@ APIError APINoiseFrameHelper::state_action_server_hello_() {
   // node mac, terminated by null byte
   std::memcpy(msg + mac_offset, mac, MAC_ADDRESS_BUFFER_SIZE);
 
-  APIError aerr = write_frame_(msg, total_size);
+  return write_frame_(msg, total_size);
+}
+APIError APINoiseFrameHelper::state_action_server_hello_() {
+  APIError aerr = this->send_server_hello_frame_();
   if (aerr != APIError::OK)
     return aerr;
-
-  // start handshake
-  aerr = init_handshake_();
+  return this->start_handshake_();
+}
+APIError APINoiseFrameHelper::start_handshake_() {
+  APIError aerr = init_handshake_();
   if (aerr != APIError::OK)
     return aerr;
-
   state_ = State::HANDSHAKE;
   return APIError::OK;
 }

esphome/components/api/api_frame_helper_noise.h

@@ -28,6 +28,12 @@ class APINoiseFrameHelper final : public APIFrameHelper {
   // Seeds the already-read header bytes and pumps the handshake state machine
   // until it would block.
   APIError init_from_handoff(const uint8_t *header, uint8_t header_len);
+#endif
+#ifdef USE_API_OUTGOING_CONNECTION
+  // Send the server hello immediately so the peer can pick the key before
+  // its PSK-mixed message. Call after init(); the mode is tracked in state_
+  // so the helper does not grow.
+  APIError send_server_hello_first();
 #endif
   APIError loop() override;
   APIError read_packet(ReadPacketBuffer *buffer) override;
@@ -39,6 +45,8 @@ class APINoiseFrameHelper final : public APIFrameHelper {
   APIError state_action_();
   APIError state_action_client_hello_();
   APIError state_action_server_hello_();
+  APIError send_server_hello_frame_();
+  APIError start_handshake_();
   APIError state_action_handshake_();
   APIError state_action_handshake_read_();
   APIError state_action_handshake_write_();

esphome/components/api/api_outgoing_connection.cpp

@@ -0,0 +1,236 @@
+#include "api_outgoing_connection.h"
+#if defined(USE_API) && defined(USE_API_OUTGOING_CONNECTION)
+
+#include "api_connection.h"
+#include "api_server.h"
+#include "esphome/components/network/util.h"
+#include "esphome/core/application.h"
+#include "esphome/core/helpers.h"
+#include "esphome/core/log.h"
+
+#include <cerrno>
+#include <cinttypes>
+#include <cstring>
+
+namespace esphome::api {
+
+static const char *const TAG = "api.outgoing";
+
+void OutgoingConnectionManager::setup() {
+#ifndef API_OUTGOING_CONNECTION_HOST
+  this->target_pref_ = global_preferences->make_preference<SavedOutgoingTarget>(629847102UL, true);
+  if (this->target_pref_.load(&this->saved_)) {
+    // Defend against a corrupt or truncated blob before the first read
+    this->saved_.host[sizeof(this->saved_.host) - 1] = '\0';
+    this->host_persisted_ = true;
+    ESP_LOGD(TAG, "Loaded target %s", this->saved_.host);
+  } else {
+    // Never saved, or the blob failed its size/CRC check
+    ESP_LOGD(TAG, "No saved target");
+    this->saved_ = {};
+  }
+#endif
+}
+
+void OutgoingConnectionManager::loop(APIServer *server) {
+  if (server->has_outgoing_target_client_()) {
+    return;  // on_target_client() already reset the dial state
+  }
+  if (this->dialed_conn_ != nullptr) {
+    // A live dialed session (flagged or not, e.g. a host: peer) is the
+    // target; a silent one dies on the handshake timeout
+    return;
+  }
+  const uint32_t now = App.get_loop_component_start_time();
+  switch (this->state_) {
+    case DialState::DIAL_STATE_IDLE:
+#ifdef USE_DEEP_SLEEP
+      // A deep sleep wake window is too short to spend on the delay
+      this->schedule_wait_(now, BACKOFF_MIN_MS);
+#else
+      // Target went away; give it the configured delay to reconnect first
+      this->schedule_wait_(now, API_OUTGOING_CONNECTION_DELAY);
+#endif
+      break;
+    case DialState::DIAL_STATE_WAITING:
+      if (now - this->state_ts_ >= this->wait_) {
+        this->try_dial_(server, now);
+      }
+      break;
+    case DialState::DIAL_STATE_CONNECTING:
+      this->poll_connect_(server, now);
+      break;
+  }
+}
+
+void OutgoingConnectionManager::try_dial_(APIServer *server, uint32_t now) {
+  if (!network::is_connected()) {
+    // Flips within seconds of boot; recheck fast so a deep sleep wake
+    // window is not spent waiting
+    this->schedule_wait_(now, NETWORK_RETRY_MS);
+    return;
+  }
+  const char *host = this->target_host_();
+  if (host == nullptr) {
+    // The steady state until a dial-back client has ever connected
+    ESP_LOGV(TAG, "Not dialing: no target");
+    this->schedule_wait_(now, PRECONDITION_RETRY_MS);
+    return;
+  }
+  const bool at_limit = server->at_client_limit_();
+  if (at_limit || !server->noise_ctx_.has_psk()) {
+    ESP_LOGD(TAG, "Not dialing: %s", at_limit ? "max connections" : "no key");
+    // Not a dial failure; retry without escalating the backoff
+    this->schedule_wait_(now, PRECONDITION_RETRY_MS);
+    return;
+  }
+  struct sockaddr_storage addr;
+  socklen_t addr_len =
+      socket::set_sockaddr((struct sockaddr *) &addr, sizeof(addr), host, API_OUTGOING_CONNECTION_PORT);
+  if (addr_len == 0) {
+    ESP_LOGW(TAG, "Invalid target %s", host);
+#ifndef API_OUTGOING_CONNECTION_HOST
+    // A corrupt remembered value can never become dialable; forget it
+    // (covers an IPv6 literal left by an earlier enable_ipv6 build too)
+    this->saved_ = {};
+    if (!this->persist_target_()) {
+      ESP_LOGW(TAG, "Failed to clear target");
+    }
+#endif
+    this->schedule_retry_(now);
+    return;
+  }
+  this->dial_socket_ = socket::socket_loop_monitored(((struct sockaddr *) &addr)->sa_family, SOCK_STREAM, IPPROTO_TCP);
+  if (!this->dial_socket_ || this->dial_socket_->setblocking(false) != 0) {
+    ESP_LOGW(TAG, "Socket %s failed: errno %d", this->dial_socket_ ? "setblocking" : "create", errno);
+    this->schedule_retry_(now);
+    return;
+  }
+  ESP_LOGD(TAG, "Dialing %s:%u", host, API_OUTGOING_CONNECTION_PORT);
+  int err = this->dial_socket_->connect((struct sockaddr *) &addr, addr_len);
+  if (err == 0) {
+    // Immediate success (possible for localhost)
+    this->handoff_(server, now);
+    return;
+  }
+  if (errno != EINPROGRESS) {
+    ESP_LOGW(TAG, "Connect failed: errno %d", errno);
+    this->schedule_retry_(now);
+    return;
+  }
+  this->state_ = DialState::DIAL_STATE_CONNECTING;
+  this->state_ts_ = now;
+  this->last_poll_ = now;
+}
+
+void OutgoingConnectionManager::poll_connect_(APIServer *server, uint32_t now) {
+  if (now - this->state_ts_ >= CONNECT_TIMEOUT_MS) {
+    ESP_LOGW(TAG, "Connect timeout");
+    this->schedule_retry_(now);
+    return;
+  }
+  if (now - this->last_poll_ < CONNECT_POLL_INTERVAL_MS) {
+    return;
+  }
+  this->last_poll_ = now;
+  int err = 0;
+  switch (socket::poll_connect(*this->dial_socket_, err)) {
+    case socket::ConnectPollResult::CONNECT_POLL_PENDING:
+      break;
+    case socket::ConnectPollResult::CONNECT_POLL_CONNECTED:
+      this->handoff_(server, now);
+      break;
+    case socket::ConnectPollResult::CONNECT_POLL_ERROR:
+      ESP_LOGW(TAG, "Connect failed: %d", err);
+      this->schedule_retry_(now);
+      break;
+  }
+}
+
+void OutgoingConnectionManager::handoff_(APIServer *server, uint32_t now) {
+  this->dialed_conn_ = server->add_outgoing_client_(std::move(this->dial_socket_));
+  if (this->dialed_conn_ == nullptr) {
+    // Only preconditions (slot limit, key cleared) refuse the handoff; the
+    // peer is reachable, so do not escalate the backoff
+    this->schedule_wait_(now, PRECONDITION_RETRY_MS);
+    return;
+  }
+  // Connected; dialed_conn_ gates further dialing until the session settles
+  this->state_ = DialState::DIAL_STATE_IDLE;
+}
+
+void OutgoingConnectionManager::schedule_wait_(uint32_t now, uint32_t wait) {
+  this->dial_socket_.reset();  // no-op when the socket was handed off
+  this->state_ = DialState::DIAL_STATE_WAITING;
+  this->state_ts_ = now;
+  this->wait_ = wait;
+}
+
+void OutgoingConnectionManager::schedule_retry_(uint32_t now) {
+  // +/-20% jitter so a fleet of devices does not retry one server in lockstep
+  const uint32_t jitter_span = this->backoff_ / 5;
+  this->schedule_wait_(now, this->backoff_ - jitter_span + (random_uint32() % (2 * jitter_span + 1)));
+  this->backoff_ = std::min(this->backoff_ * 2, BACKOFF_MAX_MS);
+}
+
+void OutgoingConnectionManager::on_client_removed(APIConnection *conn, bool was_authenticated) {
+  if (conn != this->dialed_conn_) {
+    return;
+  }
+  this->dialed_conn_ = nullptr;
+  if (was_authenticated) {
+    // A working peer (e.g. a host: target that never sends the flag)
+    // disconnected normally; state is IDLE, so loop() applies the delay
+    this->backoff_ = BACKOFF_MIN_MS;
+  } else {
+    this->schedule_retry_(App.get_loop_component_start_time());
+  }
+}
+
+void OutgoingConnectionManager::on_target_client(APIConnection *conn) {
+  // The target is connected; stop any dial in flight and reset the backoff.
+  // A dialed connection stays tracked unless it is this one: an inbound
+  // target must not orphan a still-open dial.
+  this->dial_socket_.reset();
+  if (conn == this->dialed_conn_) {
+    this->dialed_conn_ = nullptr;
+  }
+  this->state_ = DialState::DIAL_STATE_IDLE;
+  this->backoff_ = BACKOFF_MIN_MS;
+#ifndef API_OUTGOING_CONNECTION_HOST
+  SavedOutgoingTarget target{};
+  conn->get_peername_to(target.host);
+  if (target.host[0] == '\0') {
+    ESP_LOGW(TAG, "Could not read peer address; not remembering target");
+    return;
+  }
+  if (this->host_persisted_ && strcmp(target.host, this->saved_.host) == 0) {
+    return;  // unchanged and already on flash; avoid flash wear
+  }
+  // Use the fresh address this boot even if the flash write fails; a failed
+  // write is retried on the next flagged hello via host_persisted_
+  this->saved_ = target;
+  if (!this->persist_target_()) {
+    ESP_LOGW(TAG, "Failed to save target");
+    return;
+  }
+  ESP_LOGD(TAG, "Saved %s as outgoing connection target", this->saved_.host);
+#endif
+}
+
+void OutgoingConnectionManager::dump_config() const {
+  const char *host = this->target_host_();
+  if (host == nullptr) {
+    host = "none remembered yet";
+  }
+  // The boot delay differs from delay: on deep sleep builds, so print the
+  // value that actually applies
+  ESP_LOGCONFIG(TAG,
+                "  Outgoing connection port: %u\n"
+                "  Outgoing connection host: %s\n"
+                "  Outgoing connection boot delay: %" PRIu32 "ms",
+                API_OUTGOING_CONNECTION_PORT, host, BOOT_WAIT_MS);
+}
+
+}  // namespace esphome::api
+#endif  // USE_API && USE_API_OUTGOING_CONNECTION

esphome/components/api/api_outgoing_connection.h

@@ -0,0 +1,117 @@
+#pragma once
+
+#include "esphome/core/defines.h"
+#if defined(USE_API) && defined(USE_API_OUTGOING_CONNECTION)
+
+#ifdef USE_SOCKET_IMPL_LWIP_TCP
+#error "api outgoing_connection needs a socket implementation that can make outgoing connections"
+#endif
+#ifndef USE_API_NOISE
+#error "api outgoing_connection needs noise encryption so the peer is verified by key"
+#endif
+
+#include "esphome/components/socket/socket.h"
+#include "esphome/core/preferences.h"
+
+#include <memory>
+
+namespace esphome::api {
+
+class APIServer;
+class APIConnection;
+
+// Follows the build's address family (ifdef'd in socket/headers.h): toggling
+// enable_ipv6 changes the blob size, load() rejects the old blob, and the
+// target is simply relearned
+static constexpr size_t SAVED_TARGET_HOST_LEN = socket::SOCKADDR_STR_LEN;
+
+struct SavedOutgoingTarget {
+  // IP as text so the socket component's v4-mapped-IPv6 normalization is
+  // reused on both ends; empty = none remembered
+  char host[SAVED_TARGET_HOST_LEN];
+} PACKED;  // NOLINT
+
+/// Dials out when no dial-back target client is connected. Only the TCP
+/// direction flips: the device stays the Noise responder, so both sides
+/// still verify by key. Targets the YAML host or the last remembered client.
+class OutgoingConnectionManager {
+ public:
+  void setup();
+  void loop(APIServer *server);
+  /// A key-verified client declared itself a dial-back target; last one wins
+  void on_target_client(APIConnection *conn);
+  /// Clears the dialed-connection gate; dying unauthenticated escalates the backoff
+  void on_client_removed(APIConnection *conn, bool was_authenticated);
+  void on_shutdown() { this->dial_socket_.reset(); }
+  void dump_config() const;
+
+ protected:
+  enum class DialState : uint8_t {
+    DIAL_STATE_IDLE,
+    DIAL_STATE_WAITING,
+    DIAL_STATE_CONNECTING,
+  };
+
+  static constexpr uint32_t BACKOFF_MIN_MS = 5000;
+  static constexpr uint32_t BACKOFF_MAX_MS = 300000;
+  static constexpr uint32_t CONNECT_TIMEOUT_MS = 10000;
+  static constexpr uint32_t CONNECT_POLL_INTERVAL_MS = 250;
+  static constexpr uint32_t NETWORK_RETRY_MS = 500;
+  static constexpr uint32_t PRECONDITION_RETRY_MS = 5000;
+  // Boot waits for the client to connect in first; a deep sleep wake window
+  // is short, so connecting out immediately is the wake state
+#ifdef USE_DEEP_SLEEP
+  static constexpr uint32_t BOOT_WAIT_MS = 0;
+#else
+  static constexpr uint32_t BOOT_WAIT_MS = API_OUTGOING_CONNECTION_DELAY;
+#endif
+
+  void try_dial_(APIServer *server, uint32_t now);
+  void poll_connect_(APIServer *server, uint32_t now);
+  // Hand the connected socket to the server and gate on the new connection
+  void handoff_(APIServer *server, uint32_t now);
+  // Close any half-open dial and wait a jittered backoff before retrying
+  void schedule_retry_(uint32_t now);
+  // Wait without escalating the backoff (used for unmet preconditions)
+  void schedule_wait_(uint32_t now, uint32_t wait);
+#ifndef API_OUTGOING_CONNECTION_HOST
+  // Write saved_ to flash, tracking success in host_persisted_
+  bool persist_target_() {
+    this->host_persisted_ = this->target_pref_.save(&this->saved_) && global_preferences->sync();
+    return this->host_persisted_;
+  }
+#endif
+  const char *target_host_() const {
+#ifdef API_OUTGOING_CONNECTION_HOST
+    return API_OUTGOING_CONNECTION_HOST;
+#else
+    return this->saved_.host[0] != '\0' ? this->saved_.host : nullptr;
+#endif
+  }
+
+  // Pointers first (4 bytes each on 32-bit)
+  std::unique_ptr<socket::Socket> dial_socket_;
+  // Compared only, never dereferenced
+  APIConnection *dialed_conn_{nullptr};
+#ifndef API_OUTGOING_CONNECTION_HOST
+  ESPPreferenceObject target_pref_;
+#endif
+
+  // 4-byte types
+  uint32_t backoff_{BACKOFF_MIN_MS};
+  uint32_t wait_{BOOT_WAIT_MS};
+  uint32_t state_ts_{0};
+  uint32_t last_poll_{0};
+
+  // Byte-aligned types last
+#ifndef API_OUTGOING_CONNECTION_HOST
+  SavedOutgoingTarget saved_{};
+  // False while saved_ holds a value the flash write failed for; retried on
+  // the next flagged hello
+  bool host_persisted_{false};
+#endif
+  DialState state_{DialState::DIAL_STATE_WAITING};
+};
+
+}  // namespace esphome::api
+#endif  // USE_API && USE_API_OUTGOING_CONNECTION

esphome/components/api/api_pb2.cpp

@@ -15,6 +15,11 @@ bool HelloRequest::decode_varint(uint32_t field_id, proto_varint_value_t value)
     case 3:
       this->api_version_minor = value;
       break;
+#ifdef USE_API_OUTGOING_CONNECTION
+    case 4:
+      this->outgoing_connection_target = value != 0;
+      break;
+#endif
     default:
       return false;
   }
@@ -175,6 +180,9 @@ uint8_t *DeviceInfoResponse::encode(ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_
 #endif
 #ifdef USE_API_NOISE
   ProtoEncode::encode_bool(pos PROTO_ENCODE_DEBUG_ARG, 26, this->api_encryption_provisionable);
+#endif
+#ifdef USE_API_OUTGOING_CONNECTION
+  ProtoEncode::encode_bool(pos PROTO_ENCODE_DEBUG_ARG, 27, this->api_outgoing_connection_supported);
 #endif
   return pos;
 }
@@ -240,6 +248,9 @@ uint32_t DeviceInfoResponse::calculate_size() const {
 #endif
 #ifdef USE_API_NOISE
   size += ProtoSize::calc_bool(2, this->api_encryption_provisionable);
+#endif
+#ifdef USE_API_OUTGOING_CONNECTION
+  size += ProtoSize::calc_bool(2, this->api_outgoing_connection_supported);
 #endif
   return size;
 }
@@ -4253,6 +4264,19 @@ uint32_t SerialProxyRequestResponse::calculate_size() const {
   size += ProtoSize::calc_length(1, this->error_message.size());
   return size;
 }
+bool SerialProxySetModeRequest::decode_varint(uint32_t field_id, proto_varint_value_t value) {
+  switch (field_id) {
+    case 1:
+      this->instance = value;
+      break;
+    case 2:
+      this->mode = static_cast<enums::SerialProxyMode>(value);
+      break;
+    default:
+      return false;
+  }
+  return true;
+}
 #endif
 #ifdef USE_BLUETOOTH_PROXY_CONNECTIONS
 bool BluetoothSetConnectionParamsRequest::decode_varint(uint32_t field_id, proto_varint_value_t value) {

esphome/components/api/api_pb2.h

@@ -356,6 +356,7 @@ enum SerialProxyRequestType : uint32_t {
   SERIAL_PROXY_REQUEST_TYPE_FLUSH = 2,
   SERIAL_PROXY_REQUEST_TYPE_CONFIGURE = 3,
   SERIAL_PROXY_REQUEST_TYPE_SET_MODEM_PINS = 4,
+  SERIAL_PROXY_REQUEST_TYPE_SET_MODE = 5,
 };
 enum SerialProxyStatus : uint32_t {
   SERIAL_PROXY_STATUS_OK = 0,
@@ -366,6 +367,10 @@ enum SerialProxyStatus : uint32_t {
   SERIAL_PROXY_STATUS_PORT_IN_USE = 5,
   SERIAL_PROXY_STATUS_INVALID_ARGUMENT = 6,
 };
+enum SerialProxyMode : uint32_t {
+  SERIAL_PROXY_MODE_RAW = 0,
+  SERIAL_PROXY_MODE_PROTOCOL = 1,
+};
 #endif
 
 }  // namespace enums
@@ -412,13 +417,16 @@ class CommandProtoMessage : public ProtoDecodableMessage {
 class HelloRequest final : public ProtoDecodableMessage {
  public:
   static constexpr uint16_t MESSAGE_TYPE = 1;
-  static constexpr uint8_t ESTIMATED_SIZE = 17;
+  static constexpr uint8_t ESTIMATED_SIZE = 19;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const LogString *message_name() const override { return LOG_STR("hello_request"); }
 #endif
   StringRef client_info{};
   uint32_t api_version_major{0};
   uint32_t api_version_minor{0};
+#ifdef USE_API_OUTGOING_CONNECTION
+  bool outgoing_connection_target{false};
+#endif
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *dump_to(DumpBuffer &out) const override;
 #endif
@@ -549,7 +557,7 @@ class SerialProxyInfo final : public ProtoMessage {
 class DeviceInfoResponse final : public ProtoMessage {
  public:
   static constexpr uint16_t MESSAGE_TYPE = 10;
-  static constexpr uint16_t ESTIMATED_SIZE = 312;
+  static constexpr uint16_t ESTIMATED_SIZE = 315;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const LogString *message_name() const override { return LOG_STR("device_info_response"); }
 #endif
@@ -607,6 +615,9 @@ class DeviceInfoResponse final : public ProtoMessage {
 #endif
 #ifdef USE_API_NOISE
   bool api_encryption_provisionable{false};
+#endif
+#ifdef USE_API_OUTGOING_CONNECTION
+  bool api_outgoing_connection_supported{false};
 #endif
   uint8_t *encode(ProtoWriteBuffer &buffer PROTO_ENCODE_DEBUG_PARAM) const;
   uint32_t calculate_size() const;
@@ -3403,6 +3414,22 @@ class SerialProxyRequestResponse final : public ProtoMessage {
 
  protected:
 };
+class SerialProxySetModeRequest final : public ProtoDecodableMessage {
+ public:
+  static constexpr uint16_t MESSAGE_TYPE = 152;
+  static constexpr uint8_t ESTIMATED_SIZE = 6;
+#ifdef HAS_PROTO_MESSAGE_DUMP
+  const LogString *message_name() const override { return LOG_STR("serial_proxy_set_mode_request"); }
+#endif
+  uint32_t instance{0};
+  enums::SerialProxyMode mode{};
+#ifdef HAS_PROTO_MESSAGE_DUMP
+  const char *dump_to(DumpBuffer &out) const override;
+#endif
+
+ protected:
+  bool decode_varint(uint32_t field_id, proto_varint_value_t value) override;
+};
 #endif
 #ifdef USE_BLUETOOTH_PROXY_CONNECTIONS
 class BluetoothSetConnectionParamsRequest final : public ProtoDecodableMessage {

esphome/components/api/api_pb2_dump.cpp

@@ -854,6 +854,8 @@ template<> const char *proto_enum_to_string<enums::SerialProxyRequestType>(enums
       return ESPHOME_PSTR("SERIAL_PROXY_REQUEST_TYPE_CONFIGURE");
     case enums::SERIAL_PROXY_REQUEST_TYPE_SET_MODEM_PINS:
       return ESPHOME_PSTR("SERIAL_PROXY_REQUEST_TYPE_SET_MODEM_PINS");
+    case enums::SERIAL_PROXY_REQUEST_TYPE_SET_MODE:
+      return ESPHOME_PSTR("SERIAL_PROXY_REQUEST_TYPE_SET_MODE");
     default:
       return ESPHOME_PSTR("UNKNOWN");
   }
@@ -878,6 +880,16 @@ template<> const char *proto_enum_to_string<enums::SerialProxyStatus>(enums::Ser
       return ESPHOME_PSTR("UNKNOWN");
   }
 }
+template<> const char *proto_enum_to_string<enums::SerialProxyMode>(enums::SerialProxyMode value) {
+  switch (value) {
+    case enums::SERIAL_PROXY_MODE_RAW:
+      return ESPHOME_PSTR("SERIAL_PROXY_MODE_RAW");
+    case enums::SERIAL_PROXY_MODE_PROTOCOL:
+      return ESPHOME_PSTR("SERIAL_PROXY_MODE_PROTOCOL");
+    default:
+      return ESPHOME_PSTR("UNKNOWN");
+  }
+}
 #endif
 
 const char *HelloRequest::dump_to(DumpBuffer &out) const {
@@ -885,6 +897,9 @@ const char *HelloRequest::dump_to(DumpBuffer &out) const {
   dump_field(out, ESPHOME_PSTR("client_info"), this->client_info);
   dump_field(out, ESPHOME_PSTR("api_version_major"), this->api_version_major);
   dump_field(out, ESPHOME_PSTR("api_version_minor"), this->api_version_minor);
+#ifdef USE_API_OUTGOING_CONNECTION
+  dump_field(out, ESPHOME_PSTR("outgoing_connection_target"), this->outgoing_connection_target);
+#endif
   return out.c_str();
 }
 const char *HelloResponse::dump_to(DumpBuffer &out) const {
@@ -1008,6 +1023,9 @@ const char *DeviceInfoResponse::dump_to(DumpBuffer &out) const {
 #endif
 #ifdef USE_API_NOISE
   dump_field(out, ESPHOME_PSTR("api_encryption_provisionable"), this->api_encryption_provisionable);
+#endif
+#ifdef USE_API_OUTGOING_CONNECTION
+  dump_field(out, ESPHOME_PSTR("api_outgoing_connection_supported"), this->api_outgoing_connection_supported);
 #endif
   return out.c_str();
 }
@@ -2805,6 +2823,12 @@ const char *SerialProxyRequestResponse::dump_to(DumpBuffer &out) const {
   dump_field(out, ESPHOME_PSTR("error_message"), this->error_message);
   return out.c_str();
 }
+const char *SerialProxySetModeRequest::dump_to(DumpBuffer &out) const {
+  MessageDumpHelper helper(out, ESPHOME_PSTR("SerialProxySetModeRequest"));
+  dump_field(out, ESPHOME_PSTR("instance"), this->instance);
+  dump_field(out, ESPHOME_PSTR("mode"), static_cast<enums::SerialProxyMode>(this->mode));
+  return out.c_str();
+}
 #endif
 #ifdef USE_BLUETOOTH_PROXY_CONNECTIONS
 const char *BluetoothSetConnectionParamsRequest::dump_to(DumpBuffer &out) const {

esphome/components/api/api_pb2_service.cpp

@@ -712,6 +712,17 @@ void APIConnection::read_message_(uint32_t msg_size, uint32_t msg_type, const ui
       this->on_device_capabilities_request();
       break;
     }
+#ifdef USE_SERIAL_PROXY
+    case SerialProxySetModeRequest::MESSAGE_TYPE: {
+      SerialProxySetModeRequest msg;
+      msg.decode(msg_data, msg_size);
+#ifdef HAS_PROTO_MESSAGE_DUMP
+      this->log_receive_message_(LOG_STR("on_serial_proxy_set_mode_request"), msg);
+#endif
+      this->on_serial_proxy_set_mode_request(msg);
+      break;
+    }
+#endif
     default:
       break;
   }

esphome/components/api/api_pb2_service.h

@@ -235,6 +235,9 @@ class APIServerConnectionBase {
   void on_serial_proxy_request(const SerialProxyRequest &value){};
 #endif
 
+#ifdef USE_SERIAL_PROXY
+  void on_serial_proxy_set_mode_request(const SerialProxySetModeRequest &value){};
+#endif
 #ifdef USE_BLUETOOTH_PROXY_CONNECTIONS
   void on_bluetooth_set_connection_params_request(const BluetoothSetConnectionParamsRequest &value){};
 #endif

esphome/components/api/api_server.cpp

@@ -34,7 +34,46 @@ APIServer::APIServer() { global_api_server = this; }
 void APIServer::socket_failed_(const LogString *msg) {
   ESP_LOGW(TAG, "Socket %s: errno %d", LOG_STR_ARG(msg), errno);
   this->destroy_socket_();
-  this->mark_failed();
+}
+
+bool APIServer::create_listen_socket_() {
+  this->socket_ = socket::socket_ip_loop_monitored(SOCK_STREAM, 0).release();  // monitored for incoming connections
+  if (this->socket_ == nullptr) {
+    this->socket_failed_(LOG_STR("creation"));
+    return false;
+  }
+  int enable = 1;
+  int err = this->socket_->setsockopt(SOL_SOCKET, SO_REUSEADDR, &enable, sizeof(int));
+  if (err != 0) {
+    ESP_LOGW(TAG, "Socket reuseaddr: errno %d", errno);
+    // we can still continue
+  }
+  err = this->socket_->setblocking(false);
+  if (err != 0) {
+    this->socket_failed_(LOG_STR("nonblocking"));
+    return false;
+  }
+
+  struct sockaddr_storage server;
+
+  socklen_t sl = socket::set_sockaddr_any((struct sockaddr *) &server, sizeof(server), this->port_);
+  if (sl == 0) {
+    this->socket_failed_(LOG_STR("set sockaddr"));
+    return false;
+  }
+
+  err = this->socket_->bind((struct sockaddr *) &server, sl);
+  if (err != 0) {
+    this->socket_failed_(LOG_STR("bind"));
+    return false;
+  }
+
+  err = this->socket_->listen(this->listen_backlog_);
+  if (err != 0) {
+    this->socket_failed_(LOG_STR("listen"));
+    return false;
+  }
+  return true;
 }
 
 void APIServer::setup() {
@@ -53,41 +92,14 @@ void APIServer::setup() {
 #endif
 #endif
 
-  this->socket_ = socket::socket_ip_loop_monitored(SOCK_STREAM, 0).release();  // monitored for incoming connections
-  if (this->socket_ == nullptr) {
-    this->socket_failed_(LOG_STR("creation"));
-    return;
-  }
-  int enable = 1;
-  int err = this->socket_->setsockopt(SOL_SOCKET, SO_REUSEADDR, &enable, sizeof(int));
-  if (err != 0) {
-    ESP_LOGW(TAG, "Socket reuseaddr: errno %d", errno);
-    // we can still continue
-  }
-  err = this->socket_->setblocking(false);
-  if (err != 0) {
-    this->socket_failed_(LOG_STR("nonblocking"));
-    return;
-  }
-
-  struct sockaddr_storage server;
-
-  socklen_t sl = socket::set_sockaddr_any((struct sockaddr *) &server, sizeof(server), this->port_);
-  if (sl == 0) {
-    this->socket_failed_(LOG_STR("set sockaddr"));
-    return;
-  }
-
-  err = this->socket_->bind((struct sockaddr *) &server, sl);
-  if (err != 0) {
-    this->socket_failed_(LOG_STR("bind"));
-    return;
-  }
-
-  err = this->socket_->listen(this->listen_backlog_);
-  if (err != 0) {
-    this->socket_failed_(LOG_STR("listen"));
+  if (!this->create_listen_socket_()) {
+#ifdef USE_API_OUTGOING_CONNECTION
+    // Dial-out needs no listener; degrade instead of stopping the component
+    this->status_set_error(LOG_STR("listen socket failed"));
+#else
+    this->mark_failed();
     return;
+#endif
   }
 
 #ifdef USE_LOGGER
@@ -135,6 +147,9 @@ void APIServer::setup() {
   if (this->reboot_timeout_ != 0 && !this->provisioning_pending_()) {
     this->status_set_warning(LOG_STR("waiting for client connection"));
   }
+#ifdef USE_API_OUTGOING_CONNECTION
+  this->outgoing_conn_.setup();
+#endif
 }
 
 void APIServer::loop() {
@@ -143,6 +158,12 @@ void APIServer::loop() {
     this->accept_new_connections_();
   }
 
+#ifdef USE_API_OUTGOING_CONNECTION
+  if (!this->shutting_down_) {
+    this->outgoing_conn_.loop(this);
+  }
+#endif
+
   if (this->api_connection_count_ == 0) {
     // Check reboot timeout - done in loop to avoid scheduler heap churn
     // (cancelled scheduler items sit in heap memory until their scheduled time).
@@ -151,7 +172,12 @@ void APIServer::loop() {
     if (this->reboot_timeout_ != 0 && !this->provisioning_pending_()) {
       const uint32_t now = App.get_loop_component_start_time();
       if (now - this->last_connected_ > this->reboot_timeout_) {
-        ESP_LOGE(TAG, "No clients; rebooting");
+        // Distinguish a wrong-key peer from nothing connecting at all
+        if (this->saw_unauthenticated_client_) {
+          ESP_LOGE(TAG, "Clients connected but none authenticated; rebooting");
+        } else {
+          ESP_LOGE(TAG, "No clients; rebooting");
+        }
         App.reboot();
       }
     }
@@ -203,6 +229,15 @@ void APIServer::remove_client_(uint8_t client_index) {
   std::string client_peername(client->get_peername_to(peername_buf));
 #endif
 
+  // Read before the swap-and-reset below destroys the connection
+  const bool was_authenticated = client->is_authenticated();
+#ifdef USE_API_OUTGOING_CONNECTION
+  if (client->flags_.outgoing_connection_target) {
+    this->outgoing_target_count_--;
+  }
+  this->outgoing_conn_.on_client_removed(client.get(), was_authenticated);
+#endif
+
   // Close socket now (was deferred from on_fatal_error to allow getpeername)
   client->helper_->close();
 
@@ -221,9 +256,18 @@ void APIServer::remove_client_(uint8_t client_index) {
 
   // Last client disconnected - set warning and start tracking for reboot timeout
   // (suppressed while provisioning is pending - see loop()).
+  // Refresh on every authenticated removal, not just the last one, so an
+  // unauthenticated straggler removed later (e.g. a port scan, or a dial to
+  // a host that accepts TCP but never speaks the API) cannot discard a
+  // healthy session's timestamp and trigger a spurious reboot
+  if (was_authenticated) {
+    this->last_connected_ = App.get_loop_component_start_time();
+    this->saw_unauthenticated_client_ = false;
+  } else {
+    this->saw_unauthenticated_client_ = true;
+  }
   if (this->api_connection_count_ == 0 && this->reboot_timeout_ != 0 && !this->provisioning_pending_()) {
     this->status_set_warning(LOG_STR("waiting for client connection"));
-    this->last_connected_ = App.get_loop_component_start_time();
   }
 
 #ifdef USE_API_CLIENT_DISCONNECTED_TRIGGER
@@ -245,7 +289,7 @@ void __attribute__((flatten)) APIServer::accept_new_connections_() {
     sock->getpeername_to(peername);
 
     // Check if we're at the connection limit
-    if (this->api_connection_count_ >= MAX_API_CONNECTIONS) {
+    if (this->at_client_limit_()) {
       ESP_LOGW(TAG, "Max connections (%d), rejecting %s", MAX_API_CONNECTIONS, peername);
       // Immediately close - socket destructor will handle cleanup
       sock.reset();
@@ -254,18 +298,54 @@ void __attribute__((flatten)) APIServer::accept_new_connections_() {
 
     ESP_LOGD(TAG, "Accept %s", peername);
 
-    auto *conn = new APIConnection(std::move(sock), this);
-    this->clients_[this->api_connection_count_++].reset(conn);
-    conn->start();
-
-    // First client connected - clear warning and update timestamp
-    if (this->api_connection_count_ == 1 && this->reboot_timeout_ != 0 && !this->provisioning_pending_()) {
-      this->status_clear_warning();
-      this->last_connected_ = App.get_loop_component_start_time();
-    }
+    this->add_client_(new APIConnection(std::move(sock), this));
   }
 }
 
+bool APIServer::add_client_(APIConnection *conn) {
+  if (this->at_client_limit_()) {
+    // The accept path checks first to skip the allocation; the outgoing
+    // handoff relies on this check
+    ESP_LOGW(TAG, "Max connections (%d), dropping client", MAX_API_CONNECTIONS);
+    delete conn;
+    return false;
+  }
+  this->clients_[this->api_connection_count_++].reset(conn);
+  conn->start();
+
+  // First client connected - clear warning. The reboot watchdog timestamp is
+  // refreshed when an authenticated client is removed (see remove_client_),
+  // never on bare TCP connects.
+  if (this->api_connection_count_ == 1 && this->reboot_timeout_ != 0 && !this->provisioning_pending_()) {
+    this->status_clear_warning();
+  }
+  return true;
+}
+
+#ifdef USE_API_OUTGOING_CONNECTION
+APIConnection *APIServer::add_outgoing_client_(std::unique_ptr<socket::Socket> sock) {
+  // Re-check at the handoff: the PSK may have been cleared since the dial
+  // started (mark_outgoing() needs the noise helper); add_client_ re-checks
+  // the slot limit
+  if (!this->noise_ctx_.has_psk()) {
+    ESP_LOGW(TAG, "Dropping outgoing connection (no key)");
+    return nullptr;
+  }
+  auto *conn = new APIConnection(std::move(sock), this);
+  if (!this->add_client_(conn)) {
+    return nullptr;
+  }
+  // After start(): sends our server hello first so the peer can pick the key
+  conn->mark_outgoing();
+  return conn;
+}
+
+void APIServer::on_outgoing_target_client(APIConnection *conn) {
+  this->outgoing_target_count_++;
+  this->outgoing_conn_.on_target_client(conn);
+}
+#endif
+
 void APIServer::dump_config() {
   char addr_buf[network::USE_ADDRESS_BUFFER_SIZE];
   ESP_LOGCONFIG(TAG,
@@ -282,6 +362,9 @@ void APIServer::dump_config() {
 #else
   ESP_LOGCONFIG(TAG, "  Noise encryption: NO");
 #endif
+#ifdef USE_API_OUTGOING_CONNECTION
+  this->outgoing_conn_.dump_config();
+#endif
 }
 
 void APIServer::handle_disconnect(APIConnection *conn) {}
@@ -577,6 +660,8 @@ bool APIServer::update_noise_psk_(const SavedNoisePsk &new_psk, const LogString
         if (!c->send_message(req)) {
           API_LOG_MSG_DROPPED(TAG, "Disconnect request");
         }
+        // Force it: a session from before the key was active must not survive
+        c->flags_.next_close = true;
       }
     });
   }
@@ -678,6 +763,9 @@ void APIServer::on_shutdown() {
 
   // Close the listening socket to prevent new connections
   this->destroy_socket_();
+#ifdef USE_API_OUTGOING_CONNECTION
+  this->outgoing_conn_.on_shutdown();
+#endif
 
   // Change batch delay to 5ms for quick flushing during shutdown
   this->batch_delay_ = 5;

esphome/components/api/api_server.h

@@ -11,6 +11,7 @@
 #endif
 #include "api_pb2.h"
 #include "api_pb2_service.h"
+#include "api_outgoing_connection.h"
 #include "esphome/components/socket/socket.h"
 #include "esphome/core/automation.h"
 #include "esphome/core/component.h"
@@ -86,6 +87,10 @@ class APIServer final : public Component,
   void set_noise_psk(const uint8_t *psk) { this->noise_ctx_.set_psk(psk); }
   noise::NoiseContext &get_noise_ctx() { return this->noise_ctx_; }
 #endif  // USE_API_NOISE
+#ifdef USE_API_OUTGOING_CONNECTION
+  // Called by APIConnection when a client declares itself a dial-back target in its hello
+  void on_outgoing_target_client(APIConnection *conn);
+#endif
 
   void handle_disconnect(APIConnection *conn);
 #ifdef USE_BINARY_SENSOR
@@ -263,6 +268,16 @@ class APIServer final : public Component,
  protected:
   // Accept incoming socket connections. Only called when socket has pending connections.
   void __attribute__((noinline)) accept_new_connections_();
+  // Insert a constructed connection into the client slots and start it.
+  // Takes ownership; deletes the connection and returns false at the limit
+  bool add_client_(APIConnection *conn);
+  bool at_client_limit_() const { return this->api_connection_count_ >= MAX_API_CONNECTIONS; }
+#ifdef USE_API_OUTGOING_CONNECTION
+  // Returns the new connection, or nullptr (socket dropped) when at the limit
+  APIConnection *add_outgoing_client_(std::unique_ptr<socket::Socket> sock);
+  bool has_outgoing_target_client_() const { return this->outgoing_target_count_ != 0; }
+  friend class OutgoingConnectionManager;
+#endif
   // Remove a disconnected client by index. Swaps with the last populated slot and resets it.
   void __attribute__((noinline)) remove_client_(uint8_t client_index);
 
@@ -304,6 +319,7 @@ class APIServer final : public Component,
     this->socket_ = nullptr;
   }
   void socket_failed_(const LogString *msg);
+  bool create_listen_socket_();
   // Pointers and pointer-like types first (4 bytes each)
   socket::ListenSocket *socket_{nullptr};
 #ifdef USE_API_CLIENT_CONNECTED_TRIGGER
@@ -356,8 +372,16 @@ class APIServer final : public Component,
   // Connection limits - these defaults will be overridden by config values
   // from cv.SplitDefault in __init__.py which sets platform-specific defaults.
   uint8_t listen_backlog_{4};
-  bool shutting_down_ = false;
+  // Bit-packed so the two flags share one byte
+  bool shutting_down_ : 1 = false;
+  // For the reboot log: whether any removal since the last watchdog refresh
+  // was an unauthenticated session (e.g. a wrong-key peer)
+  bool saw_unauthenticated_client_ : 1 = false;
   uint8_t api_connection_count_{0};
+#ifdef USE_API_OUTGOING_CONNECTION
+  // Connected clients whose hello declared them a dial-back target
+  uint8_t outgoing_target_count_{0};
+#endif
 #if defined(USE_PROVISIONING) && defined(USE_API_NOISE)
   // Index assigned by the provisioning manager for reporting this transport's state.
   uint8_t provisioning_source_{0};
@@ -370,6 +394,9 @@ class APIServer final : public Component,
 #endif
   ESPPreferenceObject noise_pref_;
 #endif  // USE_API_NOISE
+#ifdef USE_API_OUTGOING_CONNECTION
+  OutgoingConnectionManager outgoing_conn_;
+#endif
 };
 
 extern APIServer *global_api_server;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)

esphome/components/async_tcp/async_tcp_socket.cpp

@@ -42,7 +42,16 @@ bool AsyncClient::connect(const char *host, uint16_t port) {
     return false;
   }
 
-  socket_->setblocking(false);
+  if (socket_->setblocking(false) != 0) {
+    // Capture before the log and reset() below can clobber errno; a blocking
+    // connect()/read() would otherwise stall the whole loop
+    const int saved_errno = errno;
+    ESP_LOGE(TAG, "Failed to set nonblocking: errno %d", saved_errno);
+    socket_.reset();
+    if (error_cb_)
+      error_cb_(error_arg_, this, saved_errno);
+    return false;
+  }
 
   int err = socket_->connect((struct sockaddr *) &addr, addrlen);
   if (err == 0) {
@@ -97,45 +106,22 @@ void AsyncClient::loop() {
     return;
 
   if (connecting_) {
-    // For connecting, we need to check writability, not readability
-    // The Application's select() only monitors read FDs, so we do our own check here
-    // For ESP platforms lwip_select() might be faster, but this code isn't used
-    // on those platforms anyway. If it was, we'd fix the Application select()
-    // to report writability instead of doing it this way.
-    int fd = socket_->get_fd();
-    if (fd < 0) {
-      ESP_LOGW(TAG, "Invalid socket fd");
-      close();
-      return;
-    }
-
-    fd_set writefds;
-    FD_ZERO(&writefds);
-    FD_SET(fd, &writefds);
-
-    struct timeval tv = {0, 0};
-    int ret = select(fd + 1, nullptr, &writefds, nullptr, &tv);
-
-    if (ret > 0 && FD_ISSET(fd, &writefds)) {
-      int error = 0;
-      socklen_t len = sizeof(error);
-      if (socket_->getsockopt(SOL_SOCKET, SO_ERROR, &error, &len) == 0 && error == 0) {
+    int err = 0;
+    switch (socket::poll_connect(*socket_, err)) {
+      case socket::ConnectPollResult::CONNECT_POLL_PENDING:
+        break;
+      case socket::ConnectPollResult::CONNECT_POLL_CONNECTED:
         connecting_ = false;
         connected_ = true;
         if (connect_cb_)
           connect_cb_(connect_arg_, this);
-      } else {
-        ESP_LOGW(TAG, "Connection failed: %d", error);
+        break;
+      case socket::ConnectPollResult::CONNECT_POLL_ERROR:
+        ESP_LOGW(TAG, "Connection failed: %d", err);
         close();
         if (error_cb_)
-          error_cb_(error_arg_, this, error);
-      }
-    } else if (ret < 0) {
-      const int err = errno;
-      ESP_LOGE(TAG, "Select error: %d", err);
-      close();
-      if (error_cb_)
-        error_cb_(error_arg_, this, err);
+          error_cb_(error_arg_, this, err);
+        break;
     }
   } else if (connected_) {
     // For connected sockets, use the Application's select() results

esphome/components/const/__init__.py

@@ -23,6 +23,7 @@ CONF_ENABLE_OTA_DOWNGRADE_PROTECTION = "enable_ota_downgrade_protection"
 CONF_ENABLED = "enabled"
 CONF_GYROSCOPE_ODR = "gyroscope_odr"
 CONF_GYROSCOPE_RANGE = "gyroscope_range"
+CONF_HOST = "host"
 CONF_IAQ = "iaq"
 CONF_IGNORE_NOT_FOUND = "ignore_not_found"
 CONF_IS_WRGB = "is_wrgb"

esphome/components/deep_sleep/deep_sleep_bk72xx.cpp

@@ -44,7 +44,7 @@ bool DeepSleepComponent::prepare_to_sleep_() {
           this->status_set_warning();
           ESP_LOGV(TAG, "Waiting for pin to switch state to enter deep sleep...");
         }
-        this->next_enter_deep_sleep_ = true;
+        this->defer_sleep_();
         return false;
       }
     }

esphome/components/deep_sleep/deep_sleep_component.cpp

@@ -17,6 +17,7 @@ void DeepSleepComponent::setup() {
 
 void DeepSleepComponent::schedule_sleep_() {
   this->next_enter_deep_sleep_ = false;
+  this->disable_loop();
   const optional<uint32_t> run_duration = get_run_duration_();
   if (run_duration.has_value()) {
     ESP_LOGI(TAG, "Scheduling in %" PRIu32 " ms", *run_duration);
@@ -45,7 +46,7 @@ void DeepSleepComponent::loop() {
 
 void DeepSleepComponent::begin_sleep(bool manual) {
   if (this->prevent_ && !manual) {
-    this->next_enter_deep_sleep_ = true;
+    this->defer_sleep_();
     return;
   }
 

esphome/components/deep_sleep/deep_sleep_component.h

@@ -190,6 +190,11 @@ class DeepSleepComponent final : public Component {
   void schedule_sleep_();
   bool should_teardown_();
 
+  void defer_sleep_() {
+    this->next_enter_deep_sleep_ = true;
+    this->enable_loop();
+  }
+
 #ifdef USE_BK72XX
   bool pin_prevents_sleep_(WakeUpPinItem &pin_item) const;
   bool get_real_pin_state_(InternalGPIOPin &pin) const { return (pin.digital_read() ^ pin.is_inverted()); }

esphome/components/deep_sleep/deep_sleep_esp32.cpp

@@ -100,7 +100,7 @@ bool DeepSleepComponent::prepare_to_sleep_() {
       this->status_set_warning();
       ESP_LOGW(TAG, "Waiting for wakeup pin state change");
     }
-    this->next_enter_deep_sleep_ = true;
+    this->defer_sleep_();
     return false;
   }
   return true;

esphome/components/esphome/ota/ota_esphome.cpp

@@ -447,7 +447,10 @@ void ESPHomeOTAComponent::handle_data_() {
   tv.tv_usec = 0;
   this->client_->setsockopt(SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv));
   this->client_->setsockopt(SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv));
-  this->client_->setblocking(true);
+  if (this->client_->setblocking(true) != 0) {
+    this->log_socket_error_(LOG_STR("blocking"));
+    goto error;  // NOLINT(cppcoreguidelines-avoid-goto)
+  }
 
   // Acknowledge auth OK - 1 byte
   this->data_write_byte_(ota::OTA_RESPONSE_AUTH_OK);

esphome/components/logger/logger_esp32.cpp

@@ -3,6 +3,7 @@
 
 #include "esphome/components/esp32/crash_handler.h"
 #include <esp_log.h>
+#include <esp_idf_version.h>
 
 #include <driver/uart.h>
 #include <soc/soc_caps.h>
@@ -16,8 +17,10 @@
 #include <driver/usb_serial_jtag_vfs.h>
 #endif
 #endif
-
-#include "esp_idf_version.h"
+#if defined(CONFIG_PM_ENABLE) && defined(CONFIG_FREERTOS_USE_TICKLESS_IDLE) && \
+    (ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(6, 0, 0))
+#include "esp_sleep.h"
+#endif
 #include "freertos/FreeRTOS.h"
 
 #include <fcntl.h>
@@ -87,6 +90,12 @@ void init_uart(uart_port_t uart_num, uint32_t baud_rate, int tx_buffer_size) {
   // ESP-IDF requires rx_buffer_size > UART_HW_FIFO_LEN (128 bytes).
   const int min_rx_buffer_size = UART_HW_FIFO_LEN(uart_num) + 1;
   uart_driver_install(uart_num, min_rx_buffer_size, tx_buffer_size, 0, nullptr, 0);
+#if defined(CONFIG_PM_ENABLE) && defined(CONFIG_FREERTOS_USE_TICKLESS_IDLE) && \
+    (ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(6, 0, 0))
+  // Always flush before going to light sleep. Could be disabled for devices
+  // without TOP_PD or if source_clk = UART_SCLK_RTC
+  esp_sleep_set_console_uart_handling_mode(ESP_SLEEP_ALWAYS_FLUSH_UART);
+#endif
 }
 
 void Logger::pre_setup() {

esphome/components/mlx90614/mlx90614.cpp

@@ -26,44 +26,129 @@ static const uint8_t MLX90614_ID4 = 0x3F;
 
 static const char *const TAG = "mlx90614";
 
+// The EEPROM cell has a limited number of write cycles, so stop retrying after a few failures
+static constexpr uint8_t EMISSIVITY_WRITE_ATTEMPTS = 3;
+
+// SMBus packet error code: CRC-8 with polynomial 0x07, MSB first
+static uint8_t crc8_pec(const uint8_t *data, uint8_t len) { return crc8(data, len, 0x00, 0x07, true); }
+
 void MLX90614Component::setup() {
-  if (!this->write_emissivity_()) {
-    ESP_LOGE(TAG, ESP_LOG_MSG_COMM_FAIL);
-    this->mark_failed();
+  if (std::isnan(this->emissivity_)) {
     return;
   }
+  this->emissivity_write_attempts_ = EMISSIVITY_WRITE_ATTEMPTS;
+  this->try_write_emissivity_();
+  if (this->emissivity_write_attempts_ != 0) {
+    this->status_set_warning(LOG_STR("Failed to write emissivity, will retry"));
+  }
+}
+
+void MLX90614Component::try_write_emissivity_() {
+  if (this->emissivity_write_attempts_ == 0) {
+    return;
+  }
+  if (this->write_emissivity_()) {
+    this->emissivity_write_attempts_ = 0;
+    return;
+  }
+  if (--this->emissivity_write_attempts_ == 0) {
+    ESP_LOGE(TAG, "Giving up on writing emissivity after %u attempts", EMISSIVITY_WRITE_ATTEMPTS);
+    this->emissivity_write_failed_ = true;
+  }
 }
 
 bool MLX90614Component::write_emissivity_() {
-  if (std::isnan(this->emissivity_))
+  // Skip the write when the EEPROM already holds the desired value to save write cycles
+  uint16_t current_emissivity;
+  if (this->read_register_(MLX90614_EMISSIVITY, current_emissivity) != i2c::ERROR_OK) {
+    return false;
+  }
+
+  const auto desired_emissivity = static_cast<uint16_t>(this->emissivity_ * 0xFFFF);
+  if (current_emissivity == desired_emissivity) {
     return true;
-  uint16_t value = (uint16_t) (this->emissivity_ * 65535);
-  if (!this->write_bytes_(MLX90614_EMISSIVITY, 0)) {
-    return false;
   }
-  delay(10);
-  if (!this->write_bytes_(MLX90614_EMISSIVITY, value)) {
-    return false;
-  }
-  delay(10);
-  return true;
+
+  return this->write_register_(MLX90614_EMISSIVITY, desired_emissivity);
 }
 
-bool MLX90614Component::write_bytes_(uint8_t reg, uint16_t data) {
+bool MLX90614Component::write_register_(uint8_t reg, uint16_t data) {
+  // The PEC covers the whole write transaction: SLA+W, command, data low, data high
   uint8_t buf[5];
   buf[0] = this->address_ << 1;
   buf[1] = reg;
-  buf[2] = data & 0xFF;
-  buf[3] = data >> 8;
-  buf[4] = crc8(buf, 4, 0x00, 0x07, true);
-  return this->write_bytes(reg, buf + 2, 3);
+
+  // See datasheet 8.3.3.1 EEPROM write sequence
+  // 1. Write 0x0000 into the cell of interest (erases the cell)
+  buf[2] = buf[3] = 0;
+  buf[4] = crc8_pec(buf, 4);
+  auto ec = this->write_register(reg, buf + 2, 3);
+  if (ec != i2c::ERROR_OK) {
+    ESP_LOGW(TAG, "Can't erase register 0x%02X, error %d", reg, ec);
+    return false;
+  }
+
+  // 2. Wait at least 5ms
+  delay(10);
+
+  // 3. Write the new value
+  if (data != 0) {
+    buf[2] = data & 0xFF;
+    buf[3] = data >> 8;
+    buf[4] = crc8_pec(buf, 4);
+    ec = this->write_register(reg, buf + 2, 3);
+    if (ec != i2c::ERROR_OK) {
+      ESP_LOGW(TAG, "Can't write register 0x%02X, error %d", reg, ec);
+      return false;
+    }
+    // 4. Wait at least 5ms
+    delay(10);
+  }
+
+  // 5. Read back to confirm the value was stored
+  uint16_t read_back;
+  ec = this->read_register_(reg, read_back);
+  if (ec != i2c::ERROR_OK) {
+    ESP_LOGW(TAG, "Can't check register 0x%02X value, error %d", reg, ec);
+    return false;
+  }
+
+  if (read_back != data) {
+    ESP_LOGW(TAG, "Read back mismatch on register 0x%02X. Expected 0x%04X, got 0x%04X", reg, data, read_back);
+    return false;
+  }
+
+  return true;
+}
+
+i2c::ErrorCode MLX90614Component::read_register_(uint8_t reg, uint16_t &data) {
+  // The PEC covers the whole read transaction: SLA+W, command, SLA+R, data low, data high
+  uint8_t buf[6];
+  buf[0] = this->address_ << 1;
+  buf[1] = reg;
+  buf[2] = (this->address_ << 1) | 0x01;
+
+  const auto ec = this->read_register(reg, buf + 3, 3);
+  if (ec != i2c::ERROR_OK) {
+    ESP_LOGW(TAG, "i2c read error %d", ec);
+    return ec;
+  }
+
+  const auto expected_pec = crc8_pec(buf, 5);
+  if (buf[5] != expected_pec) {
+    ESP_LOGW(TAG, "i2c CRC error. Expected 0x%02X, got 0x%02X", expected_pec, buf[5]);
+    return i2c::ERROR_CRC;
+  }
+
+  data = encode_uint16(buf[4], buf[3]);
+  return i2c::ERROR_OK;
 }
 
 void MLX90614Component::dump_config() {
   ESP_LOGCONFIG(TAG, "MLX90614:");
   LOG_I2C_DEVICE(this);
-  if (this->is_failed()) {
-    ESP_LOGE(TAG, ESP_LOG_MSG_COMM_FAIL);
+  if (this->emissivity_write_attempts_ != 0) {
+    ESP_LOGW(TAG, "  Emissivity not written yet, will retry");
   }
   LOG_UPDATE_INTERVAL(this);
   LOG_SENSOR("  ", "Ambient", this->ambient_sensor_);
@@ -71,33 +156,41 @@ void MLX90614Component::dump_config() {
 }
 
 void MLX90614Component::update() {
-  uint8_t emissivity[3];
-  if (this->read_register(MLX90614_EMISSIVITY, emissivity, 3) != i2c::ERROR_OK) {
-    this->status_set_warning();
-    return;
+  // Temperature reads run regardless of the emissivity state so a failure still shows up as NAN
+  this->try_write_emissivity_();
+
+  // Publishes NAN on a bus or CRC failure so a stuck reading is visible instead of silently stale
+  auto publish_sensor = [this](sensor::Sensor *sensor, uint8_t reg) {
+    if (sensor == nullptr) {
+      return i2c::ERROR_OK;
+    }
+
+    uint16_t raw;
+    const auto ec = this->read_register_(reg, raw);
+    if (ec != i2c::ERROR_OK) {
+      sensor->publish_state(NAN);
+      return ec;
+    }
+
+    // Bit 15 set means the device flagged the reading as invalid
+    const float temperature = (raw & 0x8000) ? NAN : raw * 0.02f - 273.15f;
+    ESP_LOGD(TAG, "'%s': Got temperature=%.1f°C", sensor->get_name().c_str(), temperature);
+    sensor->publish_state(temperature);
+    return ec;
+  };
+
+  const auto object_ec = publish_sensor(this->object_sensor_, MLX90614_TEMPERATURE_OBJECT_1);
+  const auto ambient_ec = publish_sensor(this->ambient_sensor_, MLX90614_TEMPERATURE_AMBIENT);
+
+  if (object_ec != i2c::ERROR_OK || ambient_ec != i2c::ERROR_OK) {
+    this->status_set_warning(LOG_STR("Failed to read some sensors"));
+  } else if (this->emissivity_write_failed_) {
+    this->status_set_warning(LOG_STR("Failed to write emissivity"));
+  } else if (this->emissivity_write_attempts_ != 0) {
+    this->status_set_warning(LOG_STR("Failed to write emissivity, will retry"));
+  } else {
+    this->status_clear_warning();
   }
-  uint8_t raw_object[3];
-  if (this->read_register(MLX90614_TEMPERATURE_OBJECT_1, raw_object, 3) != i2c::ERROR_OK) {
-    this->status_set_warning();
-    return;
-  }
-
-  uint8_t raw_ambient[3];
-  if (this->read_register(MLX90614_TEMPERATURE_AMBIENT, raw_ambient, 3) != i2c::ERROR_OK) {
-    this->status_set_warning();
-    return;
-  }
-
-  float ambient = raw_ambient[1] & 0x80 ? NAN : encode_uint16(raw_ambient[1], raw_ambient[0]) * 0.02f - 273.15f;
-  float object = raw_object[1] & 0x80 ? NAN : encode_uint16(raw_object[1], raw_object[0]) * 0.02f - 273.15f;
-
-  ESP_LOGD(TAG, "Got Temperature=%.1f°C Ambient=%.1f°C", object, ambient);
-
-  if (this->ambient_sensor_ != nullptr && !std::isnan(ambient))
-    this->ambient_sensor_->publish_state(ambient);
-  if (this->object_sensor_ != nullptr && !std::isnan(object))
-    this->object_sensor_->publish_state(object);
-  this->status_clear_warning();
 }
 
 }  // namespace esphome::mlx90614

esphome/components/mlx90614/mlx90614.h

@@ -18,13 +18,18 @@ class MLX90614Component final : public PollingComponent, public i2c::I2CDevice {
   void set_emissivity(float emissivity) { emissivity_ = emissivity; }
 
  protected:
+  void try_write_emissivity_();
   bool write_emissivity_();
 
-  bool write_bytes_(uint8_t reg, uint16_t data);
+  bool write_register_(uint8_t reg, uint16_t data);
+  i2c::ErrorCode read_register_(uint8_t reg, uint16_t &data);
 
   sensor::Sensor *ambient_sensor_{nullptr};
   sensor::Sensor *object_sensor_{nullptr};
 
   float emissivity_{NAN};
+  // Remaining attempts to program the emissivity EEPROM cell, bounded to limit cell wear
+  uint8_t emissivity_write_attempts_{0};
+  bool emissivity_write_failed_{false};
 };
 }  // namespace esphome::mlx90614

esphome/components/network/util.h

@@ -26,30 +26,34 @@ namespace esphome::network {
 
 /// Return whether the node is connected to the network (through wifi, eth, ...)
 ESPHOME_ALWAYS_INLINE inline bool is_connected() {
+  // With a single interface enabled the checks below collapse to `if (x) return true; return false;`, which
+  // clang-tidy wants folded into one return. Keep the per-interface form so every enabled interface is checked.
+  // NOLINTBEGIN(readability-simplify-boolean-expr)
 #ifdef USE_ETHERNET
   if (ethernet::global_eth_component != nullptr && ethernet::global_eth_component->is_connected())
     return true;
 #endif
 
 #ifdef USE_MODEM
-  if (modem::global_modem_component != nullptr)
-    return modem::global_modem_component->is_connected();
+  if (modem::global_modem_component != nullptr && modem::global_modem_component->is_connected())
+    return true;
 #endif
 
 #ifdef USE_WIFI
-  if (wifi::global_wifi_component != nullptr)
-    return wifi::global_wifi_component->is_connected();
+  if (wifi::global_wifi_component != nullptr && wifi::global_wifi_component->is_connected())
+    return true;
 #endif
 
 #ifdef USE_OPENTHREAD
-  if (openthread::global_openthread_component != nullptr)
-    return openthread::global_openthread_component->is_connected();
+  if (openthread::global_openthread_component != nullptr && openthread::global_openthread_component->is_connected())
+    return true;
 #endif
 
 #ifdef USE_HOST
   return true;  // Assume it's connected
 #endif
   return false;
+  // NOLINTEND(readability-simplify-boolean-expr)
 }
 
 /// Return whether the network is disabled: every configured interface with a

esphome/components/serial_proxy/__init__.py

@@ -30,6 +30,7 @@ MULTI_CONF = True
 
 serial_proxy_ns = cg.esphome_ns.namespace("serial_proxy")
 SerialProxy = serial_proxy_ns.class_("SerialProxy", cg.Component, uart.UARTDevice)
+SerialProxyTap = serial_proxy_ns.class_("SerialProxyTap")
 
 api_enums_ns = cg.esphome_ns.namespace("api").namespace("enums")
 SerialProxyPortType = api_enums_ns.enum("SerialProxyPortType")

esphome/components/serial_proxy/serial_proxy.cpp

@@ -29,26 +29,57 @@ void SerialProxy::setup() {
 #ifdef USE_API
   // instance_index_ is fixed at registration time; pre-set it so loop() only needs to update data
   this->outgoing_msg_.instance = this->instance_index_;
+#endif
+#ifdef USE_SERIAL_PROXY_TAP
+  // A tap sets itself up before this runs (its setup priority is higher), so it may
+  // already be waiting on the port -- a boot-time handshake with the device, say. Leaving
+  // the loop enabled is what lets that finish; without it the tap would stall until a
+  // client happened to subscribe.
+  if (this->tap_ != nullptr && this->tap_->tap_needs_port()) {
+    return;
+  }
 #endif
   // No subscriber at startup; disable loop until a client subscribes
   this->disable_loop();
 }
 
-void SerialProxy::loop() {
-#ifdef USE_API
-  // Safety check — loop should only run when subscribed, but guard against races
-  if (this->api_connection_ == nullptr) [[unlikely]] {
-    this->disable_loop();
+#ifdef USE_SERIAL_PROXY_TAP
+void SerialProxy::reset_mode_() {
+  // The mode belongs to a session, not to the port. Carrying a departed client's choice
+  // over to the next one would inject protocol bytes into a stream that never asked for
+  // them -- a firmware upload, or any client built before this request existed and so
+  // unable to turn it off. Guessing RAW is the safe direction: a client that wanted
+  // protocol handling and did not ask for it merely sends its own acknowledgements.
+  if (this->mode_ == api::enums::SERIAL_PROXY_MODE_RAW) {
     return;
   }
+  ESP_LOGD(TAG, "Session ended, returning serial proxy [%" PRIu32 "] to RAW mode", this->instance_index_);
+  this->mode_ = api::enums::SERIAL_PROXY_MODE_RAW;
+}
+#endif
 
+void SerialProxy::loop() {
+#ifdef USE_API
   // Detect subscriber disconnect
-  if (this->api_connection_->is_marked_for_removal() || !this->api_connection_->is_connection_setup() ||
-      !api_is_connected()) {
+  if (this->api_connection_ != nullptr && (this->api_connection_->is_marked_for_removal() ||
+                                           !this->api_connection_->is_connection_setup() || !api_is_connected())) {
     ESP_LOGW(TAG, "Subscriber disconnected");
     this->api_connection_ = nullptr;
+    this->reset_mode_();
+  }
+
+  // With no subscriber there is normally nothing to do, but a tap may still need the port
+  // read -- it does its protocol work precisely while nobody else is listening.
+  if (this->api_connection_ == nullptr) [[unlikely]] {
+#ifdef USE_SERIAL_PROXY_TAP
+    if (this->tap_ == nullptr || !this->tap_->tap_needs_port()) {
+      this->disable_loop();
+      return;
+    }
+#else
     this->disable_loop();
     return;
+#endif
   }
 
   // Read available data from UART and forward to subscribed client
@@ -69,11 +100,54 @@ void __attribute__((noinline)) SerialProxy::read_and_send_(size_t available) {
   if (!this->read_array(buffer, to_read))
     return;
 
+#ifdef USE_SERIAL_PROXY_TAP
+  // Before forwarding, so a tap that answers the device (an acknowledgement, say) is not
+  // waiting on the network round trip to a subscriber that may not even exist.
+  if (this->tap_observing_()) {
+    this->tap_->on_device_rx(buffer, to_read);
+  }
+#endif
+
+  if (this->api_connection_ == nullptr) {
+    return;
+  }
   this->outgoing_msg_.set_data(buffer, to_read);
   this->api_connection_->send_serial_proxy_data(this->outgoing_msg_);
 }
 #endif
 
+#ifdef USE_SERIAL_PROXY_TAP
+
+bool SerialProxy::tap_observing_() const {
+  if (this->tap_ == nullptr) {
+    return false;
+  }
+  // With no subscriber, a tap doing its own protocol work (the boot-time handshake with
+  // the device, say) is served regardless of mode -- nobody has chosen one yet. Once a
+  // subscriber holds the port, the mode alone decides, so RAW stays inert.
+  if (this->api_connection_ == nullptr && this->tap_->tap_needs_port()) {
+    return true;
+  }
+  // Otherwise the mode decides. RAW must be inert: a client that flips to RAW before
+  // flashing firmware is entitled to a byte pipe with nothing injecting protocol bytes
+  // into it, and "the tap turned out not to recognise the stream" is not good enough.
+  return this->mode_ == api::enums::SERIAL_PROXY_MODE_PROTOCOL;
+}
+
+void SerialProxy::tap_pump() {
+#ifdef USE_API
+  // Nothing would consume the bytes; leave them in the FIFO
+  if (!this->tap_observing_() && this->api_connection_ == nullptr) {
+    return;
+  }
+  const size_t available = this->available();
+  if (available > 0) {
+    this->read_and_send_(available);
+  }
+#endif
+}
+#endif
+
 void SerialProxy::dump_config() {
   ESP_LOGCONFIG(TAG,
                 "Serial Proxy [%" PRIu32 "]:\n"
@@ -92,8 +166,9 @@ void SerialProxy::dump_config() {
 SerialProxyResult SerialProxy::configure(api::APIConnection *api_connection, uint32_t baudrate, bool flow_control,
                                          uint8_t parity, uint8_t stop_bits, uint8_t data_size) {
 #ifdef USE_API
-  if (this->port_claimed_by_other_(api_connection)) {
-    ESP_LOGW(TAG, "Ignoring configure request from client without port access [%" PRIu32 "]", this->instance_index_);
+  if (!this->is_subscriber_(api_connection)) {
+    ESP_LOGW(TAG, "Ignoring configure request from client without port subscription [%" PRIu32 "]",
+             this->instance_index_);
     return SerialProxyResult::SERIAL_PROXY_RESULT_PORT_IN_USE;
   }
 #endif
@@ -159,24 +234,80 @@ SerialProxyResult SerialProxy::configure(api::APIConnection *api_connection, uin
   return SerialProxyResult::SERIAL_PROXY_RESULT_OK;
 }
 
+SerialProxyResult SerialProxy::set_mode_from_client(api::APIConnection *api_connection,
+                                                    api::enums::SerialProxyMode mode) {
+#ifdef USE_API
+  // Only the live subscriber may change the mode, so the mode cannot outlive a session
+  if (!this->is_subscriber_(api_connection)) {
+    ESP_LOGW(TAG, "Ignoring mode request from client without port subscription [%" PRIu32 "]", this->instance_index_);
+    return SerialProxyResult::SERIAL_PROXY_RESULT_PORT_IN_USE;
+  }
+#endif
+  // Values come from a remote client
+  if (mode != api::enums::SERIAL_PROXY_MODE_RAW && mode != api::enums::SERIAL_PROXY_MODE_PROTOCOL) {
+    ESP_LOGW(TAG, "Invalid mode: %" PRIu32, static_cast<uint32_t>(mode));
+    return SerialProxyResult::SERIAL_PROXY_RESULT_INVALID_ARGUMENT;
+  }
+  // PROTOCOL on a port with no tap would be a silent no-op; refuse so the client knows
+#ifdef USE_SERIAL_PROXY_TAP
+  const bool has_tap = this->tap_ != nullptr;
+#else
+  const bool has_tap = false;
+#endif
+  if (mode == api::enums::SERIAL_PROXY_MODE_PROTOCOL && !has_tap) {
+    ESP_LOGW(TAG, "No tap on serial proxy [%" PRIu32 "]; PROTOCOL mode unavailable", this->instance_index_);
+    return SerialProxyResult::SERIAL_PROXY_RESULT_NOT_SUPPORTED;
+  }
+  ESP_LOGD(TAG, "Serial proxy [%" PRIu32 "] mode set to %s", this->instance_index_,
+           mode == api::enums::SERIAL_PROXY_MODE_PROTOCOL ? LOG_STR_LITERAL("PROTOCOL") : LOG_STR_LITERAL("RAW"));
+#ifdef USE_SERIAL_PROXY_TAP
+  const bool leaving_protocol_mode =
+      this->mode_ != api::enums::SERIAL_PROXY_MODE_RAW && mode == api::enums::SERIAL_PROXY_MODE_RAW;
+  this->mode_ = mode;
+
+  // Only for an explicit client request, not for reset_mode_() at the end of a session:
+  // an ordinary disconnect says nothing about the device, whereas a client deliberately
+  // asking for raw bytes usually precedes changing what the device is.
+  if (leaving_protocol_mode && this->tap_ != nullptr) {
+    this->tap_->on_protocol_disabled();
+  }
+#endif
+  return SerialProxyResult::SERIAL_PROXY_RESULT_OK;
+}
+
 void SerialProxy::write_from_client(api::APIConnection *api_connection, const uint8_t *data, size_t len) {
 #ifdef USE_API
-  // Bytes from a client other than the live subscriber would interleave with the
-  // subscriber's traffic on the wire
-  if (this->port_claimed_by_other_(api_connection)) {
-    ESP_LOGW(TAG, "Ignoring write from client without port access [%" PRIu32 "]", this->instance_index_);
+  // Bytes from anyone but the live subscriber would interleave with the subscriber's
+  // traffic -- or with an active tap's -- on the wire
+  if (!this->is_subscriber_(api_connection)) {
+    if (this->api_connection_ != nullptr) {
+      ESP_LOGW(TAG, "Ignoring write from client that does not hold serial proxy [%" PRIu32 "]", this->instance_index_);
+    } else {
+      // A legacy client streaming writes without subscribing would flood WARN, one per
+      // request; writes are the only high-rate, unacknowledged operation, so keep this
+      // visible without drowning the log
+      ESP_LOGV(TAG, "Ignoring write from client without port subscription [%" PRIu32 "]", this->instance_index_);
+    }
     return;
   }
 #endif
   if (data == nullptr || len == 0)
     return;
   this->write_array(data, len);
+
+#ifdef USE_SERIAL_PROXY_TAP
+  // After the write, so the tap observes the same ordering the device does
+  if (this->tap_observing_()) {
+    this->tap_->on_client_tx(data, len);
+  }
+#endif
 }
 
 SerialProxyResult SerialProxy::set_modem_pins(api::APIConnection *api_connection, uint32_t line_states) {
 #ifdef USE_API
-  if (this->port_claimed_by_other_(api_connection)) {
-    ESP_LOGW(TAG, "Ignoring modem pin request from client without port access [%" PRIu32 "]", this->instance_index_);
+  if (!this->is_subscriber_(api_connection)) {
+    ESP_LOGW(TAG, "Ignoring modem pin request from client without port subscription [%" PRIu32 "]",
+             this->instance_index_);
     return SerialProxyResult::SERIAL_PROXY_RESULT_PORT_IN_USE;
   }
 #endif
@@ -210,8 +341,8 @@ uint32_t SerialProxy::get_modem_pins() const {
 SerialProxyResult SerialProxy::flush_port(api::APIConnection *api_connection) {
 #ifdef USE_API
   // Flushing stalls the port, so it gets the same ownership check as writes
-  if (this->port_claimed_by_other_(api_connection)) {
-    ESP_LOGW(TAG, "Ignoring flush from client without port access [%" PRIu32 "]", this->instance_index_);
+  if (!this->is_subscriber_(api_connection)) {
+    ESP_LOGW(TAG, "Ignoring flush from client without port subscription [%" PRIu32 "]", this->instance_index_);
     return SerialProxyResult::SERIAL_PROXY_RESULT_PORT_IN_USE;
   }
 #endif
@@ -230,11 +361,6 @@ SerialProxyResult SerialProxy::flush_port(api::APIConnection *api_connection) {
 }
 
 #ifdef USE_API
-bool SerialProxy::port_claimed_by_other_(api::APIConnection *api_connection) const {
-  return this->api_connection_ != nullptr && this->api_connection_ != api_connection &&
-         this->api_connection_->is_connection_setup();
-}
-
 SerialProxyResult SerialProxy::serial_proxy_request(api::APIConnection *api_connection,
                                                     api::enums::SerialProxyRequestType type) {
   switch (type) {
@@ -252,6 +378,10 @@ SerialProxyResult SerialProxy::serial_proxy_request(api::APIConnection *api_conn
           return SerialProxyResult::SERIAL_PROXY_RESULT_PORT_IN_USE;
         }
         ESP_LOGW(TAG, "Previous subscriber disconnected; taking over subscription");
+        // End the dead client's session before starting the new one, so its mode
+        // cannot leak into a session that never asked for it
+        this->api_connection_ = nullptr;
+        this->reset_mode_();
       }
       this->api_connection_ = api_connection;
       this->enable_loop();
@@ -264,7 +394,15 @@ SerialProxyResult SerialProxy::serial_proxy_request(api::APIConnection *api_conn
         return SerialProxyResult::SERIAL_PROXY_RESULT_OK;
       }
       this->api_connection_ = nullptr;
+      this->reset_mode_();
+#ifdef USE_SERIAL_PROXY_TAP
+      // Keep the loop alive for a tap that still needs the port (mirrors loop())
+      if (this->tap_ == nullptr || !this->tap_->tap_needs_port()) {
+        this->disable_loop();
+      }
+#else
       this->disable_loop();
+#endif
       ESP_LOGV(TAG, "API connection unsubscribed from serial proxy [%" PRIu32 "]", this->instance_index_);
       return SerialProxyResult::SERIAL_PROXY_RESULT_OK;
     default:

esphome/components/serial_proxy/serial_proxy.h

@@ -26,6 +26,7 @@ class APIConnection;
 namespace enums {
 enum SerialProxyPortType : uint32_t;
 enum SerialProxyRequestType : uint32_t;
+enum SerialProxyMode : uint32_t;
 }  // namespace enums
 }  // namespace esphome::api
 
@@ -52,6 +53,36 @@ enum class SerialProxyResult : uint8_t {
 /// Maximum bytes to read from UART in a single loop iteration
 inline constexpr size_t SERIAL_PROXY_MAX_READ_SIZE = 256;
 
+#ifdef USE_SERIAL_PROXY_TAP
+/// Observes a port's traffic without owning it, and may inject bytes of its own.
+///
+/// This exists so protocol-aware behaviour can be layered onto a plain byte pipe without
+/// the pipe knowing anything about the protocol: the tap is compiled in only when some
+/// component asks for one, so a proxy carrying an RS485 meter pays nothing for it.
+///
+/// A tap is an observer, never a gatekeeper -- it cannot suppress or alter the bytes
+/// flowing in either direction, so a misbehaving tap cannot corrupt the stream.
+class SerialProxyTap {
+ public:
+  /// Bytes read from the device, before they are forwarded to any subscriber.
+  virtual void on_device_rx(const uint8_t *data, size_t len) = 0;
+
+  /// Bytes a subscriber sent towards the device, after they have been written.
+  virtual void on_client_tx(const uint8_t *data, size_t len) = 0;
+
+  /// True when the port must keep reading even with no subscriber attached, so a tap can
+  /// do its own protocol work while nobody is listening. Honoured only while no
+  /// subscriber holds the port; with one attached, the port mode alone decides.
+  virtual bool tap_needs_port() const = 0;
+
+  /// A client explicitly turned protocol handling off for this port. Distinct from the
+  /// automatic reset when a session ends: this one means a client intends to do something
+  /// else with the device -- reflash it, most likely -- so anything the tap believes about
+  /// it should be treated as suspect.
+  virtual void on_protocol_disabled() = 0;
+};
+#endif
+
 class SerialProxy final : public uart::UARTDevice, public Component {
  public:
   void setup() override;
@@ -77,6 +108,9 @@ class SerialProxy final : public uart::UARTDevice, public Component {
   /// Get the port type
   api::enums::SerialProxyPortType get_port_type() const { return this->port_type_; }
 
+  /// Handle a mode change requested by an API client
+  SerialProxyResult set_mode_from_client(api::APIConnection *api_connection, api::enums::SerialProxyMode mode);
+
   /// Configure UART parameters and apply them
   /// @param api_connection The API connection requesting the change
   /// @param baudrate Baud rate in bits per second
@@ -121,13 +155,67 @@ class SerialProxy final : public uart::UARTDevice, public Component {
   /// Set the DTR GPIO pin (from YAML configuration)
   void set_dtr_pin(GPIOPin *pin) { this->dtr_pin_ = pin; }
 
+#ifdef USE_SERIAL_PROXY_TAP
+  /// Attach a traffic observer. At most one, set once at setup time.
+  void set_tap(SerialProxyTap *tap) { this->tap_ = tap; }
+
+  /// Write bytes originating from the tap rather than from a client. Bypasses the
+  /// subscriber ownership check, but only while the tap is being served bytes -- so a
+  /// port in RAW mode with a subscriber attached stays inert. Returns false when the
+  /// bytes were dropped for that reason.
+  bool write_from_tap(const uint8_t *data, size_t len) {
+    if (!this->tap_observing_()) {
+      return false;
+    }
+    this->write_array(data, len);
+    return true;
+  }
+
+  /// Whether the tap is currently being served bytes. Can flip false with no callback
+  /// (a subscriber attaching in RAW mode, say), so a tap should check before starting
+  /// protocol work and when a reply seems overdue.
+  bool tap_is_observed() const { return this->tap_observing_(); }
+
+  /// Resume reading after a tap's needs change. loop() disables itself when there is
+  /// neither a subscriber nor a tap that wants the port, so a tap starting fresh work
+  /// must ask for it back. Must be called from the main loop.
+  void tap_request_port() { this->enable_loop(); }
+
+  /// Whether the underlying device is present. On a USB UART this tracks enumeration, so
+  /// a tap can notice the device being unplugged and plugged back in.
+  bool is_device_connected() const { return this->parent_->is_connected(); }
+
+  /// Run one read-and-dispatch cycle immediately. Lets a tap make progress before the
+  /// main loop is running -- during setup, for instance, while a component is still
+  /// blocking on can_proceed(). Must not be called from on_device_rx() or
+  /// on_client_tx(): each nested cycle costs a 256-byte stack frame.
+  void tap_pump();
+#endif
+
  protected:
 #ifdef USE_API
-  /// Read from UART and send to API client (slow path with 256-byte stack buffer)
+  /// Read from UART, hand the bytes to any tap, and forward them to a subscriber
+  /// (slow path with a 256-byte stack buffer)
   void read_and_send_(size_t available);
 
-  /// True when a live subscriber other than the given connection holds the port
-  bool port_claimed_by_other_(api::APIConnection *api_connection) const;
+  /// True when the given connection is the live subscriber. Every port operation
+  /// (write, configure, modem pins, flush, mode) requires this, so an unsubscribed
+  /// client can never share the wire with the subscriber or an active tap.
+  bool is_subscriber_(api::APIConnection *api_connection) const { return this->api_connection_ == api_connection; }
+#endif
+
+#ifdef USE_SERIAL_PROXY_TAP
+  /// Return the port to RAW when a subscriber goes away, so the mode never outlives it
+  void reset_mode_();
+#else
+  /// Without a tap, PROTOCOL is refused, so the mode is fixed at RAW and there is
+  /// nothing to reset
+  void reset_mode_() {}
+#endif
+
+#ifdef USE_SERIAL_PROXY_TAP
+  /// True when the tap should be shown the traffic passing through this port
+  bool tap_observing_() const;
 #endif
 
   /// Instance index for identifying this proxy in API messages
@@ -147,6 +235,11 @@ class SerialProxy final : public uart::UARTDevice, public Component {
   /// Port type
   api::enums::SerialProxyPortType port_type_{};
 
+#ifdef USE_SERIAL_PROXY_TAP
+  /// How the bytes passing through are treated; zero is SERIAL_PROXY_MODE_RAW
+  api::enums::SerialProxyMode mode_{};
+#endif
+
   /// Optional GPIO pins for modem control
   GPIOPin *rts_pin_{nullptr};
   GPIOPin *dtr_pin_{nullptr};
@@ -154,6 +247,10 @@ class SerialProxy final : public uart::UARTDevice, public Component {
   /// Current modem pin states
   bool rts_state_{false};
   bool dtr_state_{false};
+
+#ifdef USE_SERIAL_PROXY_TAP
+  SerialProxyTap *tap_{nullptr};
+#endif
 };
 
 }  // namespace esphome::serial_proxy

esphome/components/socket/__init__.py

@@ -17,6 +17,8 @@ CONF_IMPLEMENTATION = "implementation"
 IMPLEMENTATION_LWIP_TCP = "lwip_tcp"
 IMPLEMENTATION_LWIP_SOCKETS = "lwip_sockets"
 IMPLEMENTATION_BSD_SOCKETS = "bsd_sockets"
+# Implementations whose sockets cannot make outgoing connections
+IMPLEMENTATIONS_WITHOUT_CONNECT = frozenset({IMPLEMENTATION_LWIP_TCP})
 
 # Socket tracking infrastructure
 # Components register their socket needs and platforms read this to configure appropriately

esphome/components/socket/bsd_sockets_impl.cpp

@@ -59,13 +59,15 @@ int BSDSocketImpl::close() {
 
 int BSDSocketImpl::setblocking(bool blocking) {
   int fl = ::fcntl(this->fd_, F_GETFL, 0);
+  if (fl < 0) {
+    return fl;
+  }
   if (blocking) {
     fl &= ~O_NONBLOCK;
   } else {
     fl |= O_NONBLOCK;
   }
-  ::fcntl(this->fd_, F_SETFL, fl);
-  return 0;
+  return ::fcntl(this->fd_, F_SETFL, fl);
 }
 
 size_t BSDSocketImpl::getpeername_to(std::span<char, SOCKADDR_STR_LEN> buf) {

esphome/components/socket/lwip_sockets_impl.cpp

@@ -49,13 +49,15 @@ int LwIPSocketImpl::close() {
 
 int LwIPSocketImpl::setblocking(bool blocking) {
   int fl = lwip_fcntl(this->fd_, F_GETFL, 0);
+  if (fl < 0) {
+    return fl;
+  }
   if (blocking) {
     fl &= ~O_NONBLOCK;
   } else {
     fl |= O_NONBLOCK;
   }
-  lwip_fcntl(this->fd_, F_SETFL, fl);
-  return 0;
+  return lwip_fcntl(this->fd_, F_SETFL, fl);
 }
 
 size_t LwIPSocketImpl::getpeername_to(std::span<char, SOCKADDR_STR_LEN> buf) {

esphome/components/socket/socket.cpp

@@ -2,6 +2,9 @@
 #if defined(USE_SOCKET_IMPL_LWIP_TCP) || defined(USE_SOCKET_IMPL_LWIP_SOCKETS) || defined(USE_SOCKET_IMPL_BSD_SOCKETS)
 #include <cerrno>
 #include <cstring>
+#ifdef USE_SOCKET_IMPL_BSD_SOCKETS
+#include <sys/select.h>
+#endif
 #include <string>
 #include "esphome/core/log.h"
 #include "esphome/core/application.h"
@@ -165,7 +168,10 @@ socklen_t set_sockaddr(struct sockaddr *addr, socklen_t addrlen, const char *ip_
 #else
     // Use LWIP-specific functions
     ip6_addr_t ip6;
-    inet6_aton(ip_address, &ip6);
+    if (inet6_aton(ip_address, &ip6) == 0) {
+      errno = EINVAL;
+      return 0;
+    }
     memcpy(server->sin6_addr.un.u32_addr, ip6.addr, sizeof(ip6.addr));
 #endif
     return sizeof(sockaddr_in6);
@@ -185,12 +191,58 @@ socklen_t set_sockaddr(struct sockaddr *addr, socklen_t addrlen, const char *ip_
     return 0;
   }
 #else
-  server->sin_addr.s_addr = inet_addr(ip_address);
+  // Unlike inet_addr(), inet_aton() can signal failure while still
+  // accepting the broadcast address 255.255.255.255
+  if (inet_aton(ip_address, &server->sin_addr) == 0) {
+    errno = EINVAL;
+    return 0;
+  }
 #endif
   server->sin_port = htons(port);
   return sizeof(sockaddr_in);
 }
 
+#if defined(USE_SOCKET_IMPL_BSD_SOCKETS) || defined(USE_SOCKET_IMPL_LWIP_SOCKETS)
+ConnectPollResult poll_connect(Socket &sock, int &err_out) {
+  int fd = sock.get_fd();
+  if (fd < 0 || fd >= FD_SETSIZE) {
+    // FD_SET on either is undefined behavior
+    err_out = EBADF;
+    return ConnectPollResult::CONNECT_POLL_ERROR;
+  }
+  // Connect completion is a write event; the main loop only selects on reads
+  fd_set writefds;
+  FD_ZERO(&writefds);
+  FD_SET(fd, &writefds);
+  struct timeval tv = {0, 0};
+#ifdef USE_SOCKET_IMPL_LWIP_SOCKETS
+  // LWIP_COMPAT_SOCKETS may be off (LibreTiny), so use the lwip symbol directly
+  int ret = lwip_select(fd + 1, nullptr, &writefds, nullptr, &tv);
+#else
+  // Global-scope select: the entity namespace esphome::select shadows it here
+  int ret = ::select(fd + 1, nullptr, &writefds, nullptr, &tv);
+#endif
+  if (ret < 0) {
+    err_out = errno;
+    return ConnectPollResult::CONNECT_POLL_ERROR;
+  }
+  if (ret == 0 || !FD_ISSET(fd, &writefds)) {
+    return ConnectPollResult::CONNECT_POLL_PENDING;
+  }
+  int error = 0;
+  socklen_t len = sizeof(error);
+  if (sock.getsockopt(SOL_SOCKET, SO_ERROR, &error, &len) != 0) {
+    err_out = errno;
+    return ConnectPollResult::CONNECT_POLL_ERROR;
+  }
+  if (error != 0) {
+    err_out = error;
+    return ConnectPollResult::CONNECT_POLL_ERROR;
+  }
+  return ConnectPollResult::CONNECT_POLL_CONNECTED;
+}
+#endif
+
 socklen_t set_sockaddr_any(struct sockaddr *addr, socklen_t addrlen, uint16_t port) {
 #if USE_NETWORK_IPV6
   if (addrlen < sizeof(sockaddr_in6)) {

esphome/components/socket/socket.h

@@ -145,6 +145,19 @@ inline socklen_t set_sockaddr(struct sockaddr *addr, socklen_t addrlen, const st
 /// Set a sockaddr to the any address and specified port for the IP version used by socket_ip().
 socklen_t set_sockaddr_any(struct sockaddr *addr, socklen_t addrlen, uint16_t port);
 
+#if defined(USE_SOCKET_IMPL_BSD_SOCKETS) || defined(USE_SOCKET_IMPL_LWIP_SOCKETS)
+enum class ConnectPollResult : uint8_t {
+  CONNECT_POLL_PENDING,
+  CONNECT_POLL_CONNECTED,
+  CONNECT_POLL_ERROR,
+};
+
+/// Check a non-blocking connect() for completion without blocking. On
+/// CONNECT_POLL_ERROR, err_out holds the socket's SO_ERROR, or errno when the
+/// poll itself failed.
+ConnectPollResult poll_connect(Socket &sock, int &err_out);
+#endif
+
 /// Format sockaddr into caller-provided buffer, returns length written (excluding null)
 size_t format_sockaddr_to(const struct sockaddr *addr_ptr, socklen_t len, std::span<char, SOCKADDR_STR_LEN> buf);
 

esphome/components/statsd/__init__.py

@@ -1,5 +1,6 @@
 import esphome.codegen as cg
 from esphome.components import binary_sensor, sensor
+from esphome.components.const import CONF_HOST
 import esphome.config_validation as cv
 from esphome.const import (
     CONF_BINARY_SENSORS,
@@ -14,7 +15,6 @@ AUTO_LOAD = ["socket"]
 CODEOWNERS = ["@Links2004"]
 DEPENDENCIES = ["network"]
 
-CONF_HOST = "host"
 CONF_PREFIX = "prefix"
 
 statsd_component_ns = cg.esphome_ns.namespace("statsd")

esphome/components/template/binary_sensor/__init__.py

@@ -2,7 +2,13 @@ from esphome import automation
 import esphome.codegen as cg
 from esphome.components import binary_sensor
 import esphome.config_validation as cv
-from esphome.const import CONF_CONDITION, CONF_ID, CONF_LAMBDA, CONF_STATE
+from esphome.const import (
+    CONF_CONDITION,
+    CONF_DEVICE_CLASS,
+    CONF_ID,
+    CONF_LAMBDA,
+    CONF_STATE,
+)
 from esphome.cpp_generator import LambdaExpression
 
 from .. import template_ns
@@ -12,7 +18,11 @@ TemplateBinarySensor = template_ns.class_(
 )
 
 CONFIG_SCHEMA = (
-    binary_sensor.binary_sensor_schema(TemplateBinarySensor)
+    cv.with_visibility(
+        binary_sensor.binary_sensor_schema(TemplateBinarySensor),
+        cv.Visibility.UI,
+        CONF_DEVICE_CLASS,
+    )
     .extend(
         {
             cv.Exclusive(CONF_LAMBDA, CONF_CONDITION): cv.returning_lambda,

esphome/components/template/button/__init__.py

@@ -1,10 +1,14 @@
 from esphome.components import button
+import esphome.config_validation as cv
+from esphome.const import CONF_DEVICE_CLASS
 
 from .. import template_ns
 
 TemplateButton = template_ns.class_("TemplateButton", button.Button)
 
-CONFIG_SCHEMA = button.button_schema(TemplateButton)
+CONFIG_SCHEMA = cv.with_visibility(
+    button.button_schema(TemplateButton), cv.Visibility.UI, CONF_DEVICE_CLASS
+)
 
 
 async def to_code(config):

esphome/components/template/cover/__init__.py

@@ -6,6 +6,7 @@ from esphome.const import (
     CONF_ASSUMED_STATE,
     CONF_CLOSE_ACTION,
     CONF_CURRENT_OPERATION,
+    CONF_DEVICE_CLASS,
     CONF_ID,
     CONF_LAMBDA,
     CONF_OPEN_ACTION,
@@ -38,7 +39,11 @@ CONF_HAS_POSITION = "has_position"
 CONF_TOGGLE_ACTION = "toggle_action"
 
 CONFIG_SCHEMA = (
-    cover.cover_schema(TemplateCover)
+    cv.with_visibility(
+        cover.cover_schema(TemplateCover),
+        cv.Visibility.UI,
+        CONF_DEVICE_CLASS,
+    )
     .extend(
         {
             cv.Optional(CONF_LAMBDA): cv.returning_lambda,

esphome/components/template/event/__init__.py

@@ -1,7 +1,7 @@
 import esphome.codegen as cg
 from esphome.components import event
 import esphome.config_validation as cv
-from esphome.const import CONF_EVENT_TYPES
+from esphome.const import CONF_DEVICE_CLASS, CONF_EVENT_TYPES
 
 from .. import template_ns
 
@@ -9,7 +9,9 @@ CODEOWNERS = ["@nohat"]
 
 TemplateEvent = template_ns.class_("TemplateEvent", event.Event, cg.Component)
 
-CONFIG_SCHEMA = event.event_schema(TemplateEvent).extend(
+CONFIG_SCHEMA = cv.with_visibility(
+    event.event_schema(TemplateEvent), cv.Visibility.UI, CONF_DEVICE_CLASS
+).extend(
     {
         cv.Required(CONF_EVENT_TYPES): cv.ensure_list(cv.string_strict),
     }

esphome/components/template/number/__init__.py

@@ -3,6 +3,7 @@ import esphome.codegen as cg
 from esphome.components import number
 import esphome.config_validation as cv
 from esphome.const import (
+    CONF_DEVICE_CLASS,
     CONF_ID,
     CONF_INITIAL_VALUE,
     CONF_LAMBDA,
@@ -12,6 +13,7 @@ from esphome.const import (
     CONF_RESTORE_VALUE,
     CONF_SET_ACTION,
     CONF_STEP,
+    CONF_UNIT_OF_MEASUREMENT,
 )
 
 from .. import template_ns
@@ -46,7 +48,12 @@ def validate(config):
 
 
 CONFIG_SCHEMA = cv.All(
-    number.number_schema(TemplateNumber)
+    cv.with_visibility(
+        number.number_schema(TemplateNumber),
+        cv.Visibility.UI,
+        CONF_DEVICE_CLASS,
+        CONF_UNIT_OF_MEASUREMENT,
+    )
     .extend(
         {
             cv.Required(CONF_MAX_VALUE): cv.float_,

esphome/components/template/sensor/__init__.py

@@ -2,7 +2,16 @@ from esphome import automation
 import esphome.codegen as cg
 from esphome.components import sensor
 import esphome.config_validation as cv
-from esphome.const import CONF_ID, CONF_LAMBDA, CONF_STATE
+from esphome.const import (
+    CONF_ACCURACY_DECIMALS,
+    CONF_DEVICE_CLASS,
+    CONF_FORCE_UPDATE,
+    CONF_ID,
+    CONF_LAMBDA,
+    CONF_STATE,
+    CONF_STATE_CLASS,
+    CONF_UNIT_OF_MEASUREMENT,
+)
 
 from .. import template_ns
 
@@ -11,9 +20,14 @@ TemplateSensor = template_ns.class_(
 )
 
 CONFIG_SCHEMA = (
-    sensor.sensor_schema(
-        TemplateSensor,
-        accuracy_decimals=1,
+    cv.with_visibility(
+        sensor.sensor_schema(TemplateSensor, accuracy_decimals=1),
+        cv.Visibility.UI,
+        CONF_UNIT_OF_MEASUREMENT,
+        CONF_ACCURACY_DECIMALS,
+        CONF_DEVICE_CLASS,
+        CONF_STATE_CLASS,
+        CONF_FORCE_UPDATE,
     )
     .extend(
         {

esphome/components/template/switch/__init__.py

@@ -4,6 +4,7 @@ from esphome.components import switch
 import esphome.config_validation as cv
 from esphome.const import (
     CONF_ASSUMED_STATE,
+    CONF_DEVICE_CLASS,
     CONF_ID,
     CONF_LAMBDA,
     CONF_OPTIMISTIC,
@@ -31,7 +32,11 @@ def validate(config):
 
 
 CONFIG_SCHEMA = cv.All(
-    switch.switch_schema(TemplateSwitch)
+    cv.with_visibility(
+        switch.switch_schema(TemplateSwitch),
+        cv.Visibility.UI,
+        CONF_DEVICE_CLASS,
+    )
     .extend(
         {
             cv.Optional(CONF_LAMBDA): cv.returning_lambda,

esphome/components/template/text_sensor/__init__.py

@@ -3,7 +3,7 @@ import esphome.codegen as cg
 from esphome.components import text_sensor
 from esphome.components.text_sensor import TextSensorPublishAction
 import esphome.config_validation as cv
-from esphome.const import CONF_ID, CONF_LAMBDA, CONF_STATE
+from esphome.const import CONF_DEVICE_CLASS, CONF_ID, CONF_LAMBDA, CONF_STATE
 
 from .. import template_ns
 
@@ -12,7 +12,11 @@ TemplateTextSensor = template_ns.class_(
 )
 
 CONFIG_SCHEMA = (
-    text_sensor.text_sensor_schema()
+    cv.with_visibility(
+        text_sensor.text_sensor_schema(),
+        cv.Visibility.UI,
+        CONF_DEVICE_CLASS,
+    )
     .extend(
         {
             cv.GenerateID(): cv.declare_id(TemplateTextSensor),

esphome/components/template/valve/__init__.py

@@ -6,6 +6,7 @@ from esphome.const import (
     CONF_ASSUMED_STATE,
     CONF_CLOSE_ACTION,
     CONF_CURRENT_OPERATION,
+    CONF_DEVICE_CLASS,
     CONF_ID,
     CONF_LAMBDA,
     CONF_OPEN_ACTION,
@@ -36,7 +37,11 @@ CONF_HAS_POSITION = "has_position"
 CONF_TOGGLE_ACTION = "toggle_action"
 
 CONFIG_SCHEMA = (
-    valve.valve_schema(TemplateValve)
+    cv.with_visibility(
+        valve.valve_schema(TemplateValve),
+        cv.Visibility.UI,
+        CONF_DEVICE_CLASS,
+    )
     .extend(
         {
             cv.Optional(CONF_LAMBDA): cv.returning_lambda,

esphome/components/udp/udp_component.cpp

@@ -13,9 +13,16 @@ void UDPComponent::setup() {
 #if defined(USE_SOCKET_IMPL_BSD_SOCKETS) || defined(USE_SOCKET_IMPL_LWIP_SOCKETS)
   for (const auto &address : this->addresses_) {
     struct sockaddr saddr {};
-    socket::set_sockaddr(&saddr, sizeof(saddr), address, this->broadcast_port_);
+    if (socket::set_sockaddr(&saddr, sizeof(saddr), address, this->broadcast_port_) == 0) {
+      ESP_LOGW(TAG, "Invalid address %s", address);
+      continue;
+    }
     this->sockaddrs_.push_back(saddr);
   }
+  if (this->sockaddrs_.size() != this->addresses_.size()) {
+    // A dropped address silently receives nothing; surface the misconfiguration
+    this->status_set_warning(LOG_STR("invalid address"));
+  }
   // set up broadcast socket
   if (this->should_broadcast_) {
     this->broadcast_socket_ = socket::socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
@@ -94,9 +101,15 @@ void UDPComponent::setup() {
   // 8266 and RP2040 `Duino
   for (const auto &address : this->addresses_) {
     auto ipaddr = IPAddress();
-    ipaddr.fromString(address);
+    if (!ipaddr.fromString(address)) {
+      ESP_LOGW(TAG, "Invalid address %s", address);
+      continue;
+    }
     this->ipaddrs_.push_back(ipaddr);
   }
+  if (this->ipaddrs_.size() != this->addresses_.size()) {
+    this->status_set_warning(LOG_STR("invalid address"));
+  }
   if (this->should_listen_)
     this->udp_client_.begin(this->listen_port_);
 #endif

esphome/components/wake_on_lan/wake_on_lan.cpp

@@ -34,6 +34,10 @@ void WakeOnLanButton::press_action() {
   struct sockaddr_storage saddr {};
   auto addr_len =
       socket::set_sockaddr(reinterpret_cast<sockaddr *>(&saddr), sizeof(saddr), "255.255.255.255", this->port_);
+  if (addr_len == 0) {
+    ESP_LOGW(TAG, "Invalid broadcast address");
+    return;
+  }
   uint8_t buffer[6 + sizeof this->macaddr_ * 16];
   memcpy(buffer, PREFIX, sizeof(PREFIX));
   for (size_t i = 0; i != 16; i++) {

esphome/components/zigbee/time/zigbee_time_zephyr.cpp

@@ -1,6 +1,7 @@
 #include "zigbee_time_zephyr.h"
 #if defined(USE_ZIGBEE) && defined(USE_NRF52) && defined(USE_TIME)
 #include "esphome/core/log.h"
+#include "esphome/core/application.h"
 
 namespace esphome::zigbee {
 
@@ -47,6 +48,7 @@ void ZigbeeTime::set_epoch_time(uint32_t epoch) {
     this->synchronize_epoch_(epoch);
     this->has_time_ = true;
   });
+  App.wake_loop_threadsafe();
 }
 
 void ZigbeeTime::zcl_device_cb_(zb_bufid_t bufid) {

esphome/components/zigbee/zigbee_esp32.cpp

@@ -49,7 +49,8 @@ void ZigbeeComponent::factory_reset() {
 
 void ZigbeeComponent::esp_zigbee_alarm_bdb_commissioning(ezb_bdb_comm_mode_mask_t mode) {
   if (!esp_zigbee_lock_acquire(10 / portTICK_PERIOD_MS)) {
-    global_zigbee->set_timeout("zb_init", 10, [mode]() { ZigbeeComponent::esp_zigbee_alarm_bdb_commissioning(mode); });
+    global_zigbee->set_timeout("zb_init", 100, [mode]() { ZigbeeComponent::esp_zigbee_alarm_bdb_commissioning(mode); });
+    App.wake_loop_threadsafe();
     return;
   }
   if (ezb_bdb_start_top_level_commissioning(mode) != EZB_ERR_NONE) {
@@ -88,6 +89,7 @@ bool ZigbeeComponent::app_signal_handler(const ezb_app_signal_t *app_signal) {
         global_zigbee->set_timeout("zb_init", 1000, []() {
           ZigbeeComponent::esp_zigbee_alarm_bdb_commissioning(EZB_BDB_MODE_INITIALIZATION);
         });
+        App.wake_loop_threadsafe();
       }
     } break;
     case EZB_BDB_SIGNAL_STEERING: {
@@ -113,6 +115,7 @@ bool ZigbeeComponent::app_signal_handler(const ezb_app_signal_t *app_signal) {
             ZigbeeComponent::esp_zigbee_alarm_bdb_commissioning(EZB_BDB_MODE_NETWORK_STEERING);
           });
         }
+        App.wake_loop_threadsafe();
       }
     } break;
     case EZB_ZDO_SIGNAL_LEAVE: {

esphome/components/zigbee/zigbee_zephyr.cpp

@@ -1,10 +1,10 @@
 #include "zigbee_zephyr.h"
 #if defined(USE_ZIGBEE) && defined(USE_NRF52)
 #include "esphome/core/log.h"
+#include "esphome/core/application.h"
 #include <zephyr/settings/settings.h>
 #include <zephyr/storage/flash_map.h>
 #include "esphome/core/hal.h"
-#include "esphome/core/wake.h"
 
 extern "C" {
 #include <zboss_api.h>
@@ -120,7 +120,7 @@ void ZigbeeComponent::zcl_device_cb(zb_bufid_t bufid) {
   /* Set default response value. */
   p_device_cb_param->status = RET_OK;
 
-  esphome::wake_loop_threadsafe();
+  App.wake_loop_threadsafe();
 
   // endpoints are enumerated from 1
   if (global_zigbee->callbacks_.size() >= endpoint) {
@@ -138,6 +138,7 @@ void ZigbeeComponent::on_join_(bool factory_new) {
     ESP_LOGD(TAG, "Joined the network");
     this->join_cb_.call(factory_new);
   });
+  App.wake_loop_threadsafe();
 }
 
 void ZigbeeComponent::on_start_() {
@@ -145,6 +146,7 @@ void ZigbeeComponent::on_start_() {
     ESP_LOGD(TAG, "Started zigbee stack");
     this->start_cb_.call();
   });
+  App.wake_loop_threadsafe();
 }
 
 #ifdef USE_ZIGBEE_WIPE_ON_BOOT

esphome/config_validation.py

@@ -4,6 +4,7 @@ from __future__ import annotations
 
 from collections.abc import Callable
 from contextlib import contextmanager, suppress
+import copy
 from datetime import datetime
 from ipaddress import (
     AddressValueError,
@@ -419,6 +420,37 @@ class Required(vol.Required):
         self.visibility: Visibility | None = visibility
 
 
+def with_visibility(schema: Schema, visibility: Visibility, *keys: str) -> Schema:
+    """Return a copy of ``schema`` with the given ``keys`` re-marked at ``visibility``.
+
+    Lets a platform override the editor :class:`Visibility` of fields it
+    inherits from a shared schema builder — without that builder needing a
+    visibility parameter of its own. The canonical use is a ``template``
+    platform promoting the value metadata its user is expected to define
+    (``device_class``, ``unit_of_measurement``, …) onto the main form:
+
+        CONFIG_SCHEMA = cv.with_visibility(
+            sensor.sensor_schema(TemplateSensor),
+            cv.Visibility.UI,
+            CONF_DEVICE_CLASS, CONF_UNIT_OF_MEASUREMENT,
+        )
+
+    The original marker's key, default and validator are preserved; only the
+    visibility changes, and the input ``schema`` is left untouched. Raises if
+    a requested key is not present so typos fail at schema-build time.
+    """
+    wanted = {str(k) for k in keys}
+    overrides = {}
+    for marker, validator in schema.schema.items():
+        if str(marker) in wanted:
+            marker = copy.copy(marker)
+            marker.visibility = visibility
+            overrides[marker] = validator
+    if missing := wanted - {str(m) for m in overrides}:
+        raise ValueError(f"with_visibility: keys not in schema: {sorted(missing)}")
+    return schema.extend(overrides)
+
+
 class FinalExternalInvalid(Invalid):
     """Represents an invalid value in the final validation phase where the path should not be prepended."""
 

esphome/core/defines.h

@@ -181,6 +181,7 @@
 #define USE_SENSOR
 #define USE_SENSOR_FILTER
 #define USE_SERIAL_PROXY
+#define USE_SERIAL_PROXY_TAP
 #define USE_SETUP_PRIORITY_OVERRIDE
 #define USE_STATUS_LED
 #define USE_STATUS_SENSOR
@@ -216,6 +217,11 @@
 #define USE_API_HOMEASSISTANT_SERVICES
 #define USE_API_HOMEASSISTANT_STATES
 #define USE_API_NOISE
+#if !defined(USE_ESP8266) && !defined(USE_RP2)  // raw-lwip sockets cannot make outgoing connections
+#define USE_API_OUTGOING_CONNECTION
+#define API_OUTGOING_CONNECTION_PORT 6054
+#define API_OUTGOING_CONNECTION_DELAY 60000
+#endif
 #define USE_API_VARINT64
 #define USE_API_PLAINTEXT
 #define USE_API_USER_DEFINED_ACTIONS

requirements.txt

@@ -12,7 +12,7 @@ pyserial==3.5
 platformio==6.1.19
 esptool==5.4.0
 click==8.3.3
-aioesphomeapi==46.3.0
+aioesphomeapi==46.4.0
 aiohappyeyeballs==2.7.1  # Happy Eyeballs for requests downloads; already pulled in by aioesphomeapi
 zeroconf==0.151.3
 puremagic==2.2.0

script/git-hooks/post-checkout

@@ -1,27 +1,49 @@
 #!/bin/sh
 # Prepare the dev environment for a new checkout or worktree.
 #
-# Installed into the git hooks directory by script/setup. Deliberately tiny and
-# self-contained: it stays valid on branches where script/setup does not exist,
-# and simply does nothing there.
+# Installed into the git hooks directory by script/setup.py. Deliberately tiny
+# and self-contained: it stays valid on branches where the setup script does not
+# exist, and simply does nothing there.
 
 # $3 is 1 for a branch checkout, 0 for a file checkout.
 [ "$3" = "1" ] || exit 0
 
 top=$(git rev-parse --show-toplevel 2>/dev/null) || exit 0
 
-# This also runs on ordinary branch switches, where there is nothing to do.
+# This also runs on ordinary branch switches, where there is nothing to do. Both
+# layouts are checked because git for Windows runs hooks under its own bundled
+# shell, where the environment lives in venv/Scripts rather than venv/bin.
 [ -x "$top/venv/bin/python" ] && exit 0
-[ -x "$top/script/setup" ] || exit 0
+[ -f "$top/venv/Scripts/python.exe" ] && exit 0
+
+# Branches from before the setup script moved to Python carry only the shell
+# entry point, so whichever one the checked out branch has is used.
+py=
+if [ -f "$top/script/setup.py" ]; then
+  # The interpreter goes by different names across platforms, and on Windows
+  # "python3" is often a stub that opens the app store instead of running
+  # anything, so each candidate is tried before it is used. Doing nothing is the
+  # right outcome when none of them work.
+  for candidate in "python3" "python" "py -3"; do
+    # Unquoted on purpose: the launcher candidate is a command plus a flag.
+    if $candidate -c "" >/dev/null 2>&1; then
+      py=$candidate
+      break
+    fi
+  done
+  [ -n "$py" ] || exit 0
+elif ! [ -x "$top/script/setup" ]; then
+  exit 0
+fi
 
 # Every worktree shares the hooks directory of the checkout it was created
-# from, and the script/setup run below is the one from whichever branch was just
+# from, and the setup script run below is the one from whichever branch was just
 # checked out. Older branches install their own pre-commit hook without checking
 # for a worktree: that moves the shared hook aside as pre-commit.legacy and
 # replaces it with one tied to this worktree's virtual environment, so commits
 # break in every checkout. To rule that out, the hooks directory is copied
-# before script/setup runs and put back exactly as it was afterwards, including
-# removing any file script/setup added.
+# before the setup script runs and put back exactly as it was afterwards,
+# including removing any file the setup script added.
 hooks=$(git rev-parse --path-format=absolute --git-path hooks 2>/dev/null) || exit 0
 snap=$(mktemp -d "$hooks/.post-checkout.XXXXXX") || exit 0
 cp -p "$hooks"/* "$snap"/ 2>/dev/null
@@ -29,7 +51,13 @@ cp -p "$hooks"/* "$snap"/ 2>/dev/null
 # Clear VIRTUAL_ENV so a checkout made from a shell with an environment already
 # activated still gets its own, rather than having the active one repointed at
 # this working tree.
-env -u VIRTUAL_ENV "$top/script/setup"
+unset VIRTUAL_ENV
+if [ -n "$py" ]; then
+  # Unquoted on purpose, as above.
+  $py "$top/script/setup.py"
+else
+  "$top/script/setup"
+fi
 status=$?
 
 for f in "$hooks"/*; do

script/setup

@@ -1,71 +1,7 @@
 #!/usr/bin/env bash
-# Set up ESPHome dev environment
+# Set up ESPHome dev environment.
+#
+# The work is done by setup.py, which script/setup.bat also runs, so the Unix
+# and Windows entry points share one implementation.
 
-set -e
-
-cd "$(dirname "$0")/.."
-if [ -n "$VIRTUAL_ENV" ]; then
-  # A virtual environment is already active (e.g. the devcontainer's pre-provisioned
-  # esphome-venv). Install into it rather than creating a ./venv in the workspace.
-  venv_state=active
-elif [ -x venv/bin/python ]; then
-  # Reuse the environment from an earlier run, so this script can be run again
-  # at any time to pick up dependency changes.
-  venv_state=reused
-  source venv/bin/activate
-else
-  venv_state=created
-  # --clear replaces a partial environment left behind by an interrupted run.
-  if [ -x "$(command -v uv)" ]; then
-    uv venv --clear --seed venv
-  else
-    python3 -m venv --clear venv
-  fi
-  source venv/bin/activate
-fi
-
-if ! [ -x "$(command -v uv)" ]; then
-  python3 -m pip install uv
-fi
-
-uv pip install setuptools wheel
-uv pip install -e ".[dev,test]" --config-settings editable_mode=compat
-
-# A worktree shares one git hooks directory with the main checkout it was
-# created from, so hooks are installed from the main checkout only. Installing
-# from a worktree would point the shared hook at that worktree's virtual
-# environment, breaking it for everyone once the worktree is removed.
-git_dir="$(git rev-parse --absolute-git-dir 2>/dev/null || true)"
-common_dir="$(git rev-parse --path-format=absolute --git-common-dir 2>/dev/null || true)"
-if [ -n "$common_dir" ] && [ "$git_dir" = "$common_dir" ]; then
-  # --overwrite replaces any hook already in place. Without it, prek finds a
-  # previously installed pre-commit hook, moves it aside to
-  # .git/hooks/pre-commit.legacy and keeps calling it, so every commit would
-  # run both tools.
-  prek install --overwrite
-
-  # Prepares the virtual environment for new checkouts and worktrees. Installed
-  # once here, it covers every worktree created from this checkout.
-  if [ -d "$common_dir/hooks" ]; then
-    cp script/git-hooks/post-checkout "$common_dir/hooks/post-checkout"
-    chmod +x "$common_dir/hooks/post-checkout"
-  fi
-fi
-
-mkdir -p .temp
-
-echo
-echo
-case "$venv_state" in
-  created)
-    echo "Virtual environment created at ./venv. Run 'source venv/bin/activate' to use it."
-    ;;
-  reused)
-    echo "Dependencies updated in the existing ./venv. Run 'source venv/bin/activate' to use it."
-    ;;
-  active)
-    echo "Dependencies installed into the active virtual environment:"
-    echo "  $VIRTUAL_ENV"
-    echo "It is already active in this shell, so no 'source venv/bin/activate' is needed."
-    ;;
-esac
+exec python3 "$(dirname "$0")/setup.py" "$@"

script/setup.bat

@@ -1,28 +1 @@
-@echo off
-
-if defined VIRTUAL_ENV goto :install
-
-echo Starting the Virtual Environment
-python -m venv venv
-call venv/Scripts/activate
-echo Running the Virtual Environment
-
-:install
-
-echo Installing required packages...
-
-python.exe -m pip install --upgrade pip
-
-pip3 install -r requirements.txt -r requirements_test.txt -r requirements_dev.txt
-pip3 install setuptools wheel
-pip3 install -e ".[dev,test]" --config-settings editable_mode=compat
-
-rem --overwrite replaces any hook already in place. Without it, prek finds a
-rem previously installed pre-commit hook, moves it aside to
-rem .git/hooks/pre-commit.legacy and keeps calling it, so every commit would
-rem run both tools.
-prek install --overwrite
-
-echo .
-echo .
-echo Virtual environment created. Run 'venv/Scripts/activate' to use it.
+@python "%~dp0setup.py" %*

script/setup.py

@@ -0,0 +1,222 @@
+#!/usr/bin/env python3
+"""Set up the ESPHome development environment.
+
+Shared implementation behind script/setup and script/setup.bat, so the Unix and
+Windows entry points cannot drift apart. Uses only the standard library: it runs
+before any dependency has been installed.
+"""
+
+import os
+from pathlib import Path
+import shutil
+import subprocess
+import sys
+import sysconfig
+
+MIN_PYTHON = (3, 12)
+
+ROOT = Path(__file__).resolve().parent.parent
+DEFAULT_VENV = ROOT / "venv"
+POST_CHECKOUT_HOOK = ROOT / "script" / "git-hooks" / "post-checkout"
+
+# State of the environment the dependencies end up in, used for the closing
+# message.
+VENV_ACTIVE = "active"
+VENV_REUSED = "reused"
+VENV_CREATED = "created"
+
+
+def bin_dir(venv: Path) -> Path:
+    """Return the directory holding a virtual environment's executables.
+
+    The "venv" scheme resolves to bin on Unix and Scripts on Windows, so the
+    layout does not have to be hardcoded here.
+    """
+    base = str(venv)
+    return Path(
+        sysconfig.get_path("scripts", "venv", vars={"base": base, "platbase": base})
+    )
+
+
+def venv_python(venv: Path) -> Path:
+    """Return the path to a virtual environment's interpreter."""
+    name = "python.exe" if os.name == "nt" else "python"
+    return bin_dir(venv) / name
+
+
+def run(command: list[str], env: dict[str, str] | None = None) -> None:
+    """Run a command, aborting the whole script if it fails."""
+    print(f"+ {' '.join(command)}", flush=True)
+    result = subprocess.run(command, cwd=ROOT, env=env, check=False)
+    if result.returncode != 0:
+        # Some tools fail without printing anything, so name the step that broke.
+        print(
+            f"Failed with exit code {result.returncode}: {command[0]}", file=sys.stderr
+        )
+        raise SystemExit(result.returncode)
+
+
+def git_output(*args: str) -> str:
+    """Return the trimmed output of a git command, or "" if it cannot be run."""
+    try:
+        result = subprocess.run(
+            ["git", *args], cwd=ROOT, capture_output=True, text=True, check=False
+        )
+    except OSError:
+        # Git is not required to install the dependencies, only to install hooks.
+        return ""
+    if result.returncode != 0:
+        return ""
+    return result.stdout.strip()
+
+
+def create_venv(venv: Path) -> None:
+    """Create a virtual environment, replacing anything already at the path."""
+    # --clear replaces a partial environment left behind by an interrupted run.
+    if (uv := shutil.which("uv")) is not None:
+        run([uv, "venv", "--clear", "--seed", str(venv)])
+    else:
+        run([sys.executable, "-m", "venv", "--clear", str(venv)])
+
+
+def venv_environment(venv: Path) -> dict[str, str]:
+    """Return the environment child processes need to target a virtual env.
+
+    Equivalent to sourcing the environment's activate script: tools such as uv
+    and prek pick the environment up from VIRTUAL_ENV and PATH.
+    """
+    env = dict(os.environ)
+    env["VIRTUAL_ENV"] = str(venv)
+    env.pop("PYTHONHOME", None)
+    path = str(bin_dir(venv))
+    # An empty entry would be appended if PATH is unset, and on Unix that means
+    # the working directory is searched for executables.
+    if existing := env.get("PATH"):
+        path = os.pathsep.join([path, existing])
+    env["PATH"] = path
+    return env
+
+
+def find_uv(venv: Path, env: dict[str, str]) -> str:
+    """Return the path to uv, installing it into the environment if needed."""
+    if (uv := shutil.which("uv", path=env["PATH"])) is not None:
+        return uv
+    run([str(venv_python(venv)), "-m", "pip", "install", "uv"], env=env)
+    if (uv := shutil.which("uv", path=env["PATH"])) is not None:
+        return uv
+    raise SystemExit("uv could not be installed, aborting.")
+
+
+def install_dependencies(venv: Path, env: dict[str, str]) -> None:
+    """Install ESPHome and its development dependencies into the environment."""
+    uv = find_uv(venv, env)
+    run([uv, "pip", "install", "setuptools", "wheel"], env=env)
+    # The dev and test extras pull in requirements_dev.txt and
+    # requirements_test.txt, and the package itself pulls in requirements.txt,
+    # so this single install covers every requirements file.
+    run(
+        [
+            uv,
+            "pip",
+            "install",
+            "-e",
+            ".[dev,test]",
+            "--config-settings",
+            "editable_mode=compat",
+        ],
+        env=env,
+    )
+
+
+def install_git_hooks(env: dict[str, str]) -> None:
+    """Install the git hooks, but only when run from the main checkout.
+
+    A worktree shares one git hooks directory with the main checkout it was
+    created from. Installing from a worktree would point the shared hook at that
+    worktree's virtual environment, breaking it for everyone once the worktree is
+    removed.
+    """
+    git_dir = git_output("rev-parse", "--absolute-git-dir")
+    common_dir = git_output("rev-parse", "--path-format=absolute", "--git-common-dir")
+    if not git_dir or not common_dir or Path(git_dir) != Path(common_dir):
+        return
+
+    prek = shutil.which("prek", path=env["PATH"])
+    if prek is None:
+        raise SystemExit("prek was not installed, aborting.")
+    # --overwrite replaces any hook already in place. Without it, prek finds a
+    # previously installed pre-commit hook, moves it aside to
+    # .git/hooks/pre-commit.legacy and keeps calling it, so every commit would
+    # run both tools.
+    run([prek, "install", "--overwrite"], env=env)
+
+    # Prepares the virtual environment for new checkouts and worktrees. Installed
+    # once here, it covers every worktree created from this checkout.
+    hooks_dir = Path(common_dir) / "hooks"
+    if hooks_dir.is_dir():
+        installed = hooks_dir / "post-checkout"
+        shutil.copyfile(POST_CHECKOUT_HOOK, installed)
+        installed.chmod(0o755)
+
+
+def activate_hint() -> str:
+    """Return the command that activates the environment this script creates."""
+    activate = bin_dir(DEFAULT_VENV).relative_to(ROOT) / "activate"
+    if os.name == "nt":
+        return str(activate)
+    return f"source {activate.as_posix()}"
+
+
+def report(state: str, venv: Path) -> None:
+    """Print the closing message for the environment that was set up."""
+    location = f"./{DEFAULT_VENV.name}"
+    print()
+    print()
+    if state == VENV_ACTIVE:
+        print("Dependencies installed into the active virtual environment:")
+        print(f"  {venv}")
+        print(
+            f"It is already active in this shell, so no '{activate_hint()}' is needed."
+        )
+    elif state == VENV_REUSED:
+        print(
+            f"Dependencies updated in the existing {location}. "
+            f"Run '{activate_hint()}' to use it."
+        )
+    else:
+        print(
+            f"Virtual environment created at {location}. "
+            f"Run '{activate_hint()}' to use it."
+        )
+
+
+def main() -> None:
+    """Set up the development environment."""
+    if sys.version_info < MIN_PYTHON:
+        raise SystemExit(
+            f"ESPHome needs Python {MIN_PYTHON[0]}.{MIN_PYTHON[1]} or newer, "
+            f"but this is Python {sys.version.split()[0]}."
+        )
+
+    # A virtual environment that is already active (for example the
+    # devcontainer's pre-provisioned esphome-venv) is installed into rather than
+    # creating a ./venv in the workspace.
+    if active := os.environ.get("VIRTUAL_ENV"):
+        state, venv = VENV_ACTIVE, Path(active)
+    elif venv_python(DEFAULT_VENV).is_file():
+        # Reuse the environment from an earlier run, so this script can be run
+        # again at any time to pick up dependency changes.
+        state, venv = VENV_REUSED, DEFAULT_VENV
+    else:
+        state, venv = VENV_CREATED, DEFAULT_VENV
+        create_venv(venv)
+
+    env = venv_environment(venv)
+    install_dependencies(venv, env)
+    install_git_hooks(env)
+    (ROOT / ".temp").mkdir(exist_ok=True)
+    report(state, venv)
+
+
+if __name__ == "__main__":
+    main()

sdkconfig.defaults

@@ -17,6 +17,8 @@ CONFIG_ESP_TASK_WDT_INIT=y
 CONFIG_ESP_TASK_WDT_PANIC=y
 CONFIG_ESP_TASK_WDT_CHECK_IDLE_TASK_CPU0=n
 CONFIG_ESP_TASK_WDT_CHECK_IDLE_TASK_CPU1=n
+CONFIG_FREERTOS_USE_TICKLESS_IDLE=y
+CONFIG_PM_ENABLE=y
 
 # esp32_ble
 CONFIG_BT_ENABLED=y

tests/benchmarks/stubs/esphome/components/serial_proxy/serial_proxy.h

@@ -40,6 +40,9 @@ class SerialProxy {
     return SerialProxyResult::SERIAL_PROXY_RESULT_OK;
   }
   void write_from_client(api::APIConnection *api_connection, const uint8_t *data, size_t len) {}
+  SerialProxyResult set_mode_from_client(api::APIConnection *api_connection, api::enums::SerialProxyMode mode) {
+    return SerialProxyResult::SERIAL_PROXY_RESULT_OK;
+  }
   SerialProxyResult set_modem_pins(api::APIConnection *api_connection, uint32_t line_states) {
     return SerialProxyResult::SERIAL_PROXY_RESULT_OK;
   }

tests/component_tests/api/test_outgoing_connection.py

@@ -0,0 +1,148 @@
+"""Tests for the api outgoing_connection option."""
+
+from collections.abc import Callable
+from pathlib import Path
+
+import pytest
+
+from esphome.components import socket
+from esphome.components.api import (
+    CONFIG_SCHEMA,
+    _validate_outgoing_host_ipv6,
+    _validate_outgoing_socket_implementation,
+)
+from esphome.components.esp32 import KEY_BOARD, KEY_VARIANT, VARIANT_ESP32
+import esphome.config_validation as cv
+from esphome.const import PlatformFramework
+from esphome.core import CORE
+import esphome.final_validate as fv
+from esphome.types import ConfigType
+from tests.component_tests.types import SetCoreConfigCallable
+
+KEY = "bOFFzzvfpg5DB94DuBGLXD/hMnhpDKgP9UQyBulwWVU="
+ESP32_PLATFORM_DATA = {KEY_BOARD: "esp32dev", KEY_VARIANT: VARIANT_ESP32}
+
+
+def _api_config(outgoing: ConfigType, *, encryption: bool = True) -> ConfigType:
+    config: ConfigType = {"outgoing_connection": outgoing}
+    if encryption:
+        config["encryption"] = {"key": KEY}
+    return config
+
+
+def test_outgoing_connection_generates_defines(
+    generate_main: Callable[[str | Path], str],
+) -> None:
+    """A valid config emits the compile-time defines with defaults applied."""
+    generate_main("tests/component_tests/api/test_outgoing_connection.yaml")
+
+    defines = {define.name: define.value for define in CORE.defines}
+    assert "USE_API_OUTGOING_CONNECTION" in defines
+    assert str(defines["API_OUTGOING_CONNECTION_HOST"]) == '"192.168.1.2"'
+    assert str(defines["API_OUTGOING_CONNECTION_PORT"]) == "6054"
+    assert str(defines["API_OUTGOING_CONNECTION_DELAY"]) == "60000"
+
+
+def test_outgoing_connection_defaults(
+    set_core_config: SetCoreConfigCallable,
+) -> None:
+    set_core_config(PlatformFramework.ESP32_IDF, platform_data=ESP32_PLATFORM_DATA)
+    config = CONFIG_SCHEMA(_api_config({"host": "192.168.1.2"}))
+    outgoing = config["outgoing_connection"]
+    assert outgoing["port"] == 6054
+    assert outgoing["delay"].total_milliseconds == 60000
+
+
+def test_outgoing_connection_bare_block(
+    set_core_config: SetCoreConfigCallable,
+) -> None:
+    """A bare outgoing_connection: block is valid; the device dials the
+    remembered last dial-back client."""
+    set_core_config(PlatformFramework.ESP32_IDF, platform_data=ESP32_PLATFORM_DATA)
+    config = CONFIG_SCHEMA(_api_config(None))
+    outgoing = config["outgoing_connection"]
+    assert "host" not in outgoing
+    assert outgoing["port"] == 6054
+
+
+def test_outgoing_connection_delay_bounded(
+    set_core_config: SetCoreConfigCallable,
+) -> None:
+    """A delay past half the uint32 millisecond range is rejected, not wrapped."""
+    set_core_config(PlatformFramework.ESP32_IDF, platform_data=ESP32_PLATFORM_DATA)
+    with pytest.raises(cv.Invalid, match="value must be at most"):
+        CONFIG_SCHEMA(_api_config({"delay": "60d"}))
+
+
+def test_outgoing_connection_requires_encryption(
+    set_core_config: SetCoreConfigCallable,
+) -> None:
+    set_core_config(PlatformFramework.ESP32_IDF, platform_data=ESP32_PLATFORM_DATA)
+    with pytest.raises(cv.Invalid, match="requires 'encryption'"):
+        CONFIG_SCHEMA(_api_config({"host": "192.168.1.2"}, encryption=False))
+
+
+@pytest.mark.parametrize(
+    ("platform_framework", "platform_data", "socket_conf"),
+    [
+        # The platform default on these two, resolved like AUTO_LOAD does
+        (PlatformFramework.ESP8266_ARDUINO, None, None),
+        (PlatformFramework.RP2040_ARDUINO, None, None),
+        # An explicit selection elsewhere
+        (
+            PlatformFramework.ESP32_IDF,
+            ESP32_PLATFORM_DATA,
+            {"implementation": "lwip_tcp"},
+        ),
+    ],
+)
+def test_outgoing_connection_rejects_lwip_tcp(
+    set_core_config: SetCoreConfigCallable,
+    platform_framework: PlatformFramework,
+    platform_data: ConfigType | None,
+    socket_conf: ConfigType | None,
+) -> None:
+    """The resolved lwip_tcp socket is rejected at final validate."""
+    set_core_config(platform_framework, platform_data=platform_data)
+    fv.full_config.set({"socket": socket_conf or socket.CONFIG_SCHEMA({})})
+    config = CONFIG_SCHEMA(_api_config({"host": "192.168.1.2"}))
+    with pytest.raises(cv.Invalid, match="lwip_tcp"):
+        _validate_outgoing_socket_implementation(config)
+
+
+def test_outgoing_connection_rejects_hostnames(
+    set_core_config: SetCoreConfigCallable,
+) -> None:
+    set_core_config(PlatformFramework.ESP32_IDF, platform_data=ESP32_PLATFORM_DATA)
+    with pytest.raises(cv.Invalid, match="not a valid IP address"):
+        CONFIG_SCHEMA(_api_config({"host": "homeassistant.local"}))
+
+
+def test_outgoing_connection_ipv6_host_requires_ipv6(
+    set_core_config: SetCoreConfigCallable,
+) -> None:
+    set_core_config(PlatformFramework.ESP32_IDF, platform_data=ESP32_PLATFORM_DATA)
+    config = CONFIG_SCHEMA(_api_config({"host": "fd00::1"}))
+    with pytest.raises(cv.Invalid, match="IPv6 is not"):
+        _validate_outgoing_host_ipv6(config)
+
+
+def test_outgoing_connection_ipv6_host_passes_with_ipv6_enabled(
+    set_core_config: SetCoreConfigCallable,
+) -> None:
+    set_core_config(
+        PlatformFramework.ESP32_IDF,
+        platform_data=ESP32_PLATFORM_DATA,
+        full_config={"network": {"enable_ipv6": True}},
+    )
+    config = CONFIG_SCHEMA(_api_config({"host": "fd00::1"}))
+    assert _validate_outgoing_host_ipv6(config) is config
+
+
+def test_outgoing_connection_ipv6_host_with_ipv6(
+    generate_main: Callable[[str | Path], str],
+) -> None:
+    generate_main("tests/component_tests/api/test_outgoing_connection_ipv6.yaml")
+
+    defines = {define.name: define.value for define in CORE.defines}
+    assert str(defines["API_OUTGOING_CONNECTION_HOST"]) == '"fd00::1"'

tests/component_tests/api/test_outgoing_connection.yaml

@@ -0,0 +1,17 @@
+esphome:
+  name: test
+
+esp32:
+  board: esp32dev
+
+wifi:
+  ssid: SomeNetwork
+  password: SomePassword
+
+logger:
+
+api:
+  encryption:
+    key: bOFFzzvfpg5DB94DuBGLXD/hMnhpDKgP9UQyBulwWVU=
+  outgoing_connection:
+    host: 192.168.1.2

tests/component_tests/api/test_outgoing_connection_ipv6.yaml

@@ -0,0 +1,20 @@
+esphome:
+  name: test
+
+esp32:
+  board: esp32dev
+
+wifi:
+  ssid: SomeNetwork
+  password: SomePassword
+
+network:
+  enable_ipv6: true
+
+logger:
+
+api:
+  encryption:
+    key: bOFFzzvfpg5DB94DuBGLXD/hMnhpDKgP9UQyBulwWVU=
+  outgoing_connection:
+    host: fd00::1

tests/component_tests/template/test_template_visibility.py

@@ -0,0 +1,76 @@
+"""The template platforms surface value-describing metadata on the main form.
+
+Hardware platforms get sensible defaults for unit/device_class/etc., so those
+fields fall through to the editor's advanced disclosure. A ``template`` entity
+has no such defaults -- the user is expected to define them -- so the template
+platforms pass ``visibility=cv.Visibility.UI`` to promote them onto the form.
+"""
+
+from __future__ import annotations
+
+import importlib
+
+import pytest
+
+import esphome.config_validation as cv
+
+
+def _markers(schema: cv.Schema) -> dict[str, object]:
+    s = schema
+    if hasattr(s, "validators"):
+        # cv.All -> the schema is the first validator.
+        s = s.validators[0]
+    return {str(k): k for k in s.schema}
+
+
+@pytest.mark.parametrize(
+    ("platform", "fields"),
+    [
+        (
+            "sensor",
+            [
+                "unit_of_measurement",
+                "accuracy_decimals",
+                "device_class",
+                "state_class",
+                "force_update",
+            ],
+        ),
+        ("binary_sensor", ["device_class"]),
+        ("switch", ["device_class"]),
+        ("cover", ["device_class"]),
+        ("button", ["device_class"]),
+        ("valve", ["device_class"]),
+        ("event", ["device_class"]),
+        ("text_sensor", ["device_class"]),
+        ("number", ["device_class", "unit_of_measurement"]),
+    ],
+)
+def test_template_metadata_is_ui(platform: str, fields: list[str]) -> None:
+    mod = importlib.import_module(f"esphome.components.template.{platform}")
+    markers = _markers(mod.CONFIG_SCHEMA)
+    for field in fields:
+        assert markers[field].visibility is cv.Visibility.UI, f"{platform}.{field}"
+
+
+def test_template_sensor_promotion_preserves_defaults() -> None:
+    """Promoting to UI must not drop the fields' defaults."""
+    from esphome.components.template.sensor import CONFIG_SCHEMA
+
+    markers = _markers(CONFIG_SCHEMA)
+    assert markers["accuracy_decimals"].default() == 1
+    assert markers["force_update"].default() is False
+
+
+def test_hardware_platform_metadata_not_promoted() -> None:
+    """Without ``visibility=`` the builders leave metadata unset.
+
+    Unset markers fall through to the consumer's ``Optional`` default of
+    advanced, so hardware platforms are unaffected by the template promotion.
+    """
+    from esphome.components import binary_sensor, sensor
+
+    hw_sensor = _markers(sensor.sensor_schema(device_class="temperature"))
+    assert hw_sensor["device_class"].visibility is None
+    hw_bs = _markers(binary_sensor.binary_sensor_schema(device_class="motion"))
+    assert hw_bs["device_class"].visibility is None

tests/components/api/test-outgoing-connection.bk72xx-ard.yaml

@@ -0,0 +1,13 @@
+packages:
+  common: !include common-base.yaml
+
+wifi:
+  ssid: MySSID
+  password: password1
+
+# Outgoing connection on the lwip_sockets implementation used by LibreTiny
+api:
+  encryption:
+    key: bOFFzzvfpg5DB94DuBGLXD/hMnhpDKgP9UQyBulwWVU=
+  outgoing_connection:
+    host: 192.168.1.2

tests/components/api/test-outgoing-connection.esp32-idf.yaml

@@ -0,0 +1,16 @@
+packages:
+  common: !include common-base.yaml
+
+wifi:
+  ssid: MySSID
+  password: password1
+
+# Outgoing connection: the device dials out when no dial-back client is
+# connected. Requires encryption so the peer is verified by key.
+api:
+  encryption:
+    key: bOFFzzvfpg5DB94DuBGLXD/hMnhpDKgP9UQyBulwWVU=
+  outgoing_connection:
+    host: 192.168.1.2
+    port: 6054
+    delay: 60s

tests/components/api/test-outgoing-connection.host.yaml

@@ -0,0 +1,11 @@
+packages:
+  common: !include common-base.yaml
+
+network:
+
+# No host set: the device dials the last remembered Home Assistant address
+api:
+  encryption:
+    key: bOFFzzvfpg5DB94DuBGLXD/hMnhpDKgP9UQyBulwWVU=
+  outgoing_connection:
+    delay: 30s

tests/components/serial_proxy/test-tap.esp32-idf.yaml

@@ -0,0 +1,14 @@
+substitutions:
+  tx_pin: GPIO4
+  rx_pin: GPIO5
+
+# Compile the tap code paths; no tap is attached, so this exercises the
+# null-tap branches that a normal build never defines.
+esphome:
+  platformio_options:
+    build_flags:
+      - "-DUSE_SERIAL_PROXY_TAP"
+
+packages:
+  uart: !include ../../test_build_components/common/uart/esp32-idf.yaml
+  serial_proxy: !include common.yaml

tests/integration/fixtures/api_outgoing_connection.yaml

@@ -0,0 +1,14 @@
+esphome:
+  name: outgoing-conn-test
+
+host:
+
+logger:
+
+api:
+  encryption:
+    key: bOFFzzvfpg5DB94DuBGLXD/hMnhpDKgP9UQyBulwWVU=
+  outgoing_connection:
+    host: 127.0.0.1
+    port: OUTGOING_PORT
+    delay: 1s

tests/integration/fixtures/api_outgoing_connection_remembered.yaml

@@ -0,0 +1,13 @@
+esphome:
+  name: outgoing-conn-test
+
+host:
+
+logger:
+
+api:
+  encryption:
+    key: bOFFzzvfpg5DB94DuBGLXD/hMnhpDKgP9UQyBulwWVU=
+  outgoing_connection:
+    port: OUTGOING_PORT
+    delay: 1s

tests/integration/fixtures/api_reboot_timeout_after_authenticated_disconnect.yaml

@@ -0,0 +1,7 @@
+esphome:
+  name: api-reboot-test
+host:
+api:
+  reboot_timeout: 2s  # Headroom to connect and authenticate a client first
+logger:
+  level: DEBUG

tests/integration/test_api_outgoing_connection.py

@@ -0,0 +1,175 @@
+"""Integration tests for the api outgoing_connection option.
+
+The device dials out to the test's listener when no dial-back target client is
+connected. The listener plays the Home Assistant side over the accepted socket
+using aioesphomeapi's sans-IO Noise handshake: the device sends its server
+hello first so the listener could pick the right key, and the NNpsk0 handshake
+then verifies both sides. Protocol roles stay unchanged, so the client speaks
+exactly the same frames as over a normal connection. A client becomes the
+remembered dial-back target by setting the outgoing_connection_target flag in
+its hello.
+"""
+
+from __future__ import annotations
+
+import asyncio
+import socket
+from typing import Any
+
+from aioesphomeapi import api_pb2
+import pytest
+
+from .raw_api_client import MESSAGE_TYPE_OF
+from .types import RunCompiledFunction
+
+KEY = "bOFFzzvfpg5DB94DuBGLXD/hMnhpDKgP9UQyBulwWVU="
+DEVICE_NAME = "outgoing-conn-test"
+HA_CLIENT_INFO = "Home Assistant 2026.8.0"
+# HelloRequest field 4 (outgoing_connection_target) as raw protobuf bytes; the
+# installed aioesphomeapi's api_pb2 predates the field, so append it manually.
+HELLO_TARGET_FLAG = b"\x20\x01"
+
+
+def _frame(payload: bytes) -> bytes:
+    return bytes((0x01, len(payload) >> 8, len(payload) & 0xFF)) + payload
+
+
+async def _read_frame(reader: asyncio.StreamReader, timeout: float = 10.0) -> bytes:
+    header = await asyncio.wait_for(reader.readexactly(3), timeout)
+    assert header[0] == 0x01, f"Bad frame indicator: {header[0]}"
+    return await asyncio.wait_for(
+        reader.readexactly((header[1] << 8) | header[2]), timeout
+    )
+
+
+def _check_server_hello(server_hello: bytes) -> None:
+    assert server_hello[0] == 0x01, "Bad chosen proto in server hello"
+    name, mac, _rest = server_hello[1:].split(b"\x00", 2)
+    assert name.decode() == DEVICE_NAME
+    assert len(mac) == 12, f"Expected bare MAC, got {mac!r}"
+
+
+async def _run_ha_session(
+    reader: asyncio.StreamReader,
+    writer: asyncio.StreamWriter,
+    *,
+    device_dialed_out: bool,
+) -> None:
+    """Handshake and exchange the usual first messages as Home Assistant would."""
+    # Lazy import per the module's own contract (pulls in the noise stack)
+    from aioesphomeapi.noise import NoiseHandshake
+
+    if device_dialed_out:
+        # On an outgoing connection the device announces itself first so the
+        # peer can pick the matching key before its PSK-mixed first message.
+        _check_server_hello(await _read_frame(reader))
+
+    handshake = NoiseHandshake(KEY, b"NoiseAPIInit\x00\x00")
+    writer.write(b"\x01\x00\x00" + _frame(b"\x00" + handshake.write_message()))
+    await writer.drain()
+
+    if not device_dialed_out:
+        _check_server_hello(await _read_frame(reader))
+
+    reply = await _read_frame(reader)
+    assert reply[0] == 0, f"Handshake rejected: {reply[1:].decode(errors='replace')}"
+    handshake.read_message(reply[1:])
+    encrypt_cipher, decrypt_cipher = handshake.get_ciphers()
+
+    async def transact(msg: Any, response_cls: Any, extra_payload: bytes = b"") -> Any:
+        msg_type = MESSAGE_TYPE_OF[type(msg)]
+        payload = msg.SerializeToString() + extra_payload
+        plaintext = (
+            bytes(
+                (msg_type >> 8, msg_type & 0xFF, len(payload) >> 8, len(payload) & 0xFF)
+            )
+            + payload
+        )
+        writer.write(_frame(encrypt_cipher.encrypt(plaintext)))
+        await writer.drain()
+        want = MESSAGE_TYPE_OF[response_cls]
+        while True:
+            plain = decrypt_cipher.decrypt(await _read_frame(reader))
+            if ((plain[0] << 8) | plain[1]) == want:
+                response = response_cls()
+                response.ParseFromString(bytes(plain[4:]))
+                return response
+
+    # Declare this client a dial-back target in the hello
+    await transact(
+        api_pb2.HelloRequest(client_info=HA_CLIENT_INFO),
+        api_pb2.HelloResponse,
+        extra_payload=HELLO_TARGET_FLAG,
+    )
+    device_info = await transact(
+        api_pb2.DeviceInfoRequest(), api_pb2.DeviceInfoResponse
+    )
+    assert device_info.name == DEVICE_NAME
+
+
+async def _serve_home_assistant(listener: socket.socket) -> None:
+    """Accept one dial-in from the device and run the client side over it."""
+    loop = asyncio.get_running_loop()
+    conn, _ = await asyncio.wait_for(loop.sock_accept(listener), timeout=30)
+    reader, writer = await asyncio.open_connection(sock=conn)
+    try:
+        await _run_ha_session(reader, writer, device_dialed_out=True)
+    finally:
+        writer.close()
+
+
+@pytest.mark.asyncio
+async def test_api_outgoing_connection(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+) -> None:
+    """With a configured host the device dials out and speaks the normal API."""
+    listener = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    listener.bind(("127.0.0.1", 0))
+    listener.listen(2)
+    listener.setblocking(False)
+    port = listener.getsockname()[1]
+
+    try:
+        yaml = yaml_config.replace("OUTGOING_PORT", str(port))
+        async with run_compiled(yaml):
+            await _serve_home_assistant(listener)
+    finally:
+        listener.close()
+
+
+@pytest.mark.asyncio
+async def test_api_outgoing_connection_remembered(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    unused_tcp_port: int,
+) -> None:
+    """No host configured: the device remembers the client whose hello carried
+    the dial-back flag and dials that address after a restart."""
+    listener = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    # Bound but not yet listening so first-phase dials cannot queue stale
+    # connections; whether the device attempts any dial before the restart
+    # is timing dependent and not asserted here.
+    listener.bind(("127.0.0.1", 0))
+    port = listener.getsockname()[1]
+
+    try:
+        yaml = yaml_config.replace("OUTGOING_PORT", str(port))
+
+        async with run_compiled(yaml):
+            # Connect inbound with the dial-back flag; the device persists the
+            # peer address during the hello.
+            reader, writer = await asyncio.open_connection("127.0.0.1", unused_tcp_port)
+            try:
+                await _run_ha_session(reader, writer, device_dialed_out=False)
+            finally:
+                writer.close()
+
+        # Restart with the same preferences: the device now dials the
+        # remembered address on its own.
+        listener.listen(2)
+        listener.setblocking(False)
+        async with run_compiled(yaml):
+            await _serve_home_assistant(listener)
+    finally:
+        listener.close()

tests/integration/test_api_reboot_timeout.py

@@ -5,7 +5,7 @@ import re
 
 import pytest
 
-from .types import RunCompiledFunction
+from .types import APIClientConnectedFactory, RunCompiledFunction
 
 
 @pytest.mark.asyncio
@@ -16,7 +16,9 @@ async def test_api_reboot_timeout(
     """Test that the device reboots when no API clients connect within the timeout."""
     loop = asyncio.get_running_loop()
     reboot_future = loop.create_future()
-    reboot_pattern = re.compile(r"No clients; rebooting")
+    # The harness port probe always connects without authenticating, so the
+    # reboot deterministically reports the unauthenticated form
+    reboot_pattern = re.compile(r"none authenticated; rebooting")
 
     def check_output(line: str) -> None:
         """Check output for reboot message."""
@@ -33,3 +35,30 @@ async def test_api_reboot_timeout(
             pytest.fail("Device did not reboot within expected timeout")
 
     # Test passes if we get here - reboot was detected
+
+
+@pytest.mark.asyncio
+async def test_api_reboot_timeout_after_authenticated_disconnect(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """An authenticated disconnect resets the flag; the clean branch reboots."""
+    loop = asyncio.get_running_loop()
+    reboot_future = loop.create_future()
+    reboot_pattern = re.compile(r"No clients; rebooting")
+
+    def check_output(line: str) -> None:
+        """Check output for reboot message."""
+        if not reboot_future.done() and reboot_pattern.search(line):
+            reboot_future.set_result(True)
+
+    async with run_compiled(yaml_config, line_callback=check_output):
+        # An authenticated session refreshes the watchdog and clears the
+        # unauthenticated flag the harness probe set
+        async with api_client_connected() as client:
+            await client.device_info()
+        try:
+            await asyncio.wait_for(reboot_future, timeout=5.0)
+        except TimeoutError:
+            pytest.fail("Device did not reboot within expected timeout")

tests/script/test_setup.py

@@ -0,0 +1,562 @@
+"""Tests for script/setup.py."""
+
+import importlib.util
+import os
+from pathlib import Path, PurePosixPath, PureWindowsPath
+import runpy
+import sys
+from types import ModuleType
+from unittest.mock import Mock, call, patch
+
+import pytest
+
+_SCRIPT = Path(__file__).parents[2] / "script" / "setup.py"
+
+
+def _load_module() -> ModuleType:
+    spec = importlib.util.spec_from_file_location("script_setup", _SCRIPT)
+    module = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(module)
+    return module
+
+
+@pytest.fixture
+def script_setup() -> ModuleType:
+    """Fresh import of script/setup.py, isolated from other tests."""
+    return _load_module()
+
+
+# --- bin_dir / venv_python / activate_hint -----------------------------------
+
+
+def test_bin_dir_matches_host_layout(script_setup: ModuleType, tmp_path: Path) -> None:
+    """The venv scheme resolves to Scripts on Windows and bin everywhere else."""
+    expected = "Scripts" if os.name == "nt" else "bin"
+    assert script_setup.bin_dir(tmp_path) == tmp_path / expected
+
+
+# Both flavours are exercised on every host. Pure paths are used because a real
+# Path refuses to change flavour: PosixPath cannot be built on Windows, and
+# WindowsPath cannot be built on Unix.
+
+
+def test_venv_python_posix(script_setup: ModuleType, tmp_path: Path) -> None:
+    with (
+        patch.object(
+            script_setup, "bin_dir", return_value=PurePosixPath("/x/venv/bin")
+        ),
+        patch.object(script_setup.os, "name", "posix"),
+    ):
+        result = script_setup.venv_python(tmp_path)
+    assert result == PurePosixPath("/x/venv/bin/python")
+
+
+def test_venv_python_nt(script_setup: ModuleType, tmp_path: Path) -> None:
+    with (
+        patch.object(
+            script_setup, "bin_dir", return_value=PureWindowsPath(r"C:\x\venv\Scripts")
+        ),
+        patch.object(script_setup.os, "name", "nt"),
+    ):
+        result = script_setup.venv_python(tmp_path)
+    assert result == PureWindowsPath(r"C:\x\venv\Scripts\python.exe")
+
+
+def test_activate_hint_posix(script_setup: ModuleType) -> None:
+    with (
+        patch.object(script_setup, "ROOT", PurePosixPath("/x")),
+        patch.object(
+            script_setup, "bin_dir", return_value=PurePosixPath("/x/venv/bin")
+        ),
+        patch.object(script_setup.os, "name", "posix"),
+    ):
+        hint = script_setup.activate_hint()
+    assert hint == "source venv/bin/activate"
+
+
+def test_activate_hint_nt(script_setup: ModuleType) -> None:
+    with (
+        patch.object(script_setup, "ROOT", PureWindowsPath(r"C:\x")),
+        patch.object(
+            script_setup, "bin_dir", return_value=PureWindowsPath(r"C:\x\venv\Scripts")
+        ),
+        patch.object(script_setup.os, "name", "nt"),
+    ):
+        hint = script_setup.activate_hint()
+    # The nt branch returns str(activate) as-is, skipping the "source " prefix.
+    assert hint == r"venv\Scripts\activate"
+
+
+# --- run -----------------------------------------------------------------
+
+
+def test_run_success(script_setup: ModuleType) -> None:
+    with patch.object(
+        script_setup.subprocess, "run", return_value=Mock(returncode=0)
+    ) as mock_run:
+        script_setup.run(["echo", "hi"])
+    mock_run.assert_called_once_with(
+        ["echo", "hi"], cwd=script_setup.ROOT, env=None, check=False
+    )
+
+
+def test_run_failure_raises_system_exit_with_code(
+    script_setup: ModuleType, capsys: pytest.CaptureFixture[str]
+) -> None:
+    with (
+        patch.object(script_setup.subprocess, "run", return_value=Mock(returncode=7)),
+        pytest.raises(SystemExit) as excinfo,
+    ):
+        script_setup.run(["false"])
+    assert excinfo.value.code == 7
+    assert "Failed with exit code 7: false" in capsys.readouterr().err
+
+
+# --- git_output ------------------------------------------------------------
+
+
+def test_git_output_success_strips_stdout(script_setup: ModuleType) -> None:
+    with patch.object(
+        script_setup.subprocess,
+        "run",
+        return_value=Mock(returncode=0, stdout="  /repo/.git \n"),
+    ) as mock_run:
+        result = script_setup.git_output("rev-parse", "--absolute-git-dir")
+    assert result == "/repo/.git"
+    mock_run.assert_called_once_with(
+        ["git", "rev-parse", "--absolute-git-dir"],
+        cwd=script_setup.ROOT,
+        capture_output=True,
+        text=True,
+        check=False,
+    )
+
+
+def test_git_output_nonzero_returncode_is_empty(script_setup: ModuleType) -> None:
+    with patch.object(
+        script_setup.subprocess,
+        "run",
+        return_value=Mock(returncode=1, stdout="whatever"),
+    ):
+        assert script_setup.git_output("status") == ""
+
+
+def test_git_output_oserror_is_empty(script_setup: ModuleType) -> None:
+    with patch.object(script_setup.subprocess, "run", side_effect=OSError("no git")):
+        assert script_setup.git_output("status") == ""
+
+
+# --- create_venv -----------------------------------------------------------
+
+
+def test_create_venv_uses_uv_when_present(
+    script_setup: ModuleType, tmp_path: Path
+) -> None:
+    venv = tmp_path / "venv"
+    with (
+        patch.object(script_setup.shutil, "which", return_value="/usr/bin/uv"),
+        patch.object(
+            script_setup.subprocess, "run", return_value=Mock(returncode=0)
+        ) as mock_run,
+    ):
+        script_setup.create_venv(venv)
+    mock_run.assert_called_once_with(
+        ["/usr/bin/uv", "venv", "--clear", "--seed", str(venv)],
+        cwd=script_setup.ROOT,
+        env=None,
+        check=False,
+    )
+
+
+def test_create_venv_falls_back_to_venv_module(
+    script_setup: ModuleType, tmp_path: Path
+) -> None:
+    venv = tmp_path / "venv"
+    with (
+        patch.object(script_setup.shutil, "which", return_value=None),
+        patch.object(
+            script_setup.subprocess, "run", return_value=Mock(returncode=0)
+        ) as mock_run,
+    ):
+        script_setup.create_venv(venv)
+    mock_run.assert_called_once_with(
+        [sys.executable, "-m", "venv", "--clear", str(venv)],
+        cwd=script_setup.ROOT,
+        env=None,
+        check=False,
+    )
+
+
+# --- venv_environment --------------------------------------------------------
+
+
+def test_venv_environment_sets_virtual_env_and_prepends_path(
+    script_setup: ModuleType, tmp_path: Path, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    venv = tmp_path / "venv"
+    monkeypatch.setenv("PYTHONHOME", "/somewhere")
+    monkeypatch.setenv("PATH", "/usr/bin:/bin")
+    env = script_setup.venv_environment(venv)
+    assert env["VIRTUAL_ENV"] == str(venv)
+    assert "PYTHONHOME" not in env
+    expected_prefix = str(script_setup.bin_dir(venv)) + os.pathsep
+    assert env["PATH"] == expected_prefix + "/usr/bin:/bin"
+
+
+def test_venv_environment_path_fallback_when_unset(
+    script_setup: ModuleType, tmp_path: Path, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    venv = tmp_path / "venv"
+    monkeypatch.delenv("PATH", raising=False)
+    env = script_setup.venv_environment(venv)
+    # No trailing separator: an empty PATH entry means "search the cwd".
+    assert env["PATH"] == str(script_setup.bin_dir(venv))
+
+
+# --- find_uv -----------------------------------------------------------------
+
+
+def test_find_uv_found_immediately(script_setup: ModuleType, tmp_path: Path) -> None:
+    venv = tmp_path / "venv"
+    env = {"PATH": "/usr/bin"}
+    with (
+        patch.object(script_setup.shutil, "which", return_value="/usr/bin/uv"),
+        patch.object(script_setup.subprocess, "run") as mock_run,
+    ):
+        result = script_setup.find_uv(venv, env)
+    assert result == "/usr/bin/uv"
+    mock_run.assert_not_called()
+
+
+def test_find_uv_installed_then_found(script_setup: ModuleType, tmp_path: Path) -> None:
+    venv = tmp_path / "venv"
+    env = {"PATH": "/usr/bin"}
+    with (
+        patch.object(script_setup.shutil, "which", side_effect=[None, "/usr/bin/uv"]),
+        patch.object(
+            script_setup.subprocess, "run", return_value=Mock(returncode=0)
+        ) as mock_run,
+    ):
+        result = script_setup.find_uv(venv, env)
+    assert result == "/usr/bin/uv"
+    mock_run.assert_called_once_with(
+        [str(script_setup.venv_python(venv)), "-m", "pip", "install", "uv"],
+        cwd=script_setup.ROOT,
+        env=env,
+        check=False,
+    )
+
+
+def test_find_uv_still_missing_raises_system_exit(
+    script_setup: ModuleType, tmp_path: Path
+) -> None:
+    venv = tmp_path / "venv"
+    env = {"PATH": "/usr/bin"}
+    with (
+        patch.object(script_setup.shutil, "which", side_effect=[None, None]),
+        patch.object(script_setup.subprocess, "run", return_value=Mock(returncode=0)),
+        pytest.raises(SystemExit, match="uv could not be installed"),
+    ):
+        script_setup.find_uv(venv, env)
+
+
+# --- install_dependencies -----------------------------------------------------
+
+
+def test_install_dependencies_installs_setuptools_then_project(
+    script_setup: ModuleType, tmp_path: Path
+) -> None:
+    venv = tmp_path / "venv"
+    env = {"PATH": "/usr/bin"}
+    with (
+        patch.object(script_setup.shutil, "which", return_value="/usr/bin/uv"),
+        patch.object(
+            script_setup.subprocess, "run", return_value=Mock(returncode=0)
+        ) as mock_run,
+    ):
+        script_setup.install_dependencies(venv, env)
+    assert mock_run.call_args_list == [
+        call(
+            ["/usr/bin/uv", "pip", "install", "setuptools", "wheel"],
+            cwd=script_setup.ROOT,
+            env=env,
+            check=False,
+        ),
+        call(
+            [
+                "/usr/bin/uv",
+                "pip",
+                "install",
+                "-e",
+                ".[dev,test]",
+                "--config-settings",
+                "editable_mode=compat",
+            ],
+            cwd=script_setup.ROOT,
+            env=env,
+            check=False,
+        ),
+    ]
+
+
+# --- install_git_hooks ---------------------------------------------------------
+
+
+def _fake_git_output(git_dir: str, common_dir: str):
+    def _run(*args: str) -> str:
+        if "--absolute-git-dir" in args:
+            return git_dir
+        return common_dir
+
+    return _run
+
+
+def test_install_git_hooks_returns_early_when_git_dir_empty(
+    script_setup: ModuleType,
+) -> None:
+    env = {"PATH": "/usr/bin"}
+    with (
+        patch.object(
+            script_setup, "git_output", side_effect=_fake_git_output("", "/repo/.git")
+        ),
+        patch.object(script_setup.subprocess, "run") as mock_run,
+    ):
+        script_setup.install_git_hooks(env)
+    mock_run.assert_not_called()
+
+
+def test_install_git_hooks_returns_early_when_common_dir_empty(
+    script_setup: ModuleType,
+) -> None:
+    env = {"PATH": "/usr/bin"}
+    with (
+        patch.object(
+            script_setup, "git_output", side_effect=_fake_git_output("/repo/.git", "")
+        ),
+        patch.object(script_setup.subprocess, "run") as mock_run,
+    ):
+        script_setup.install_git_hooks(env)
+    mock_run.assert_not_called()
+
+
+def test_install_git_hooks_returns_early_for_worktree(
+    script_setup: ModuleType,
+) -> None:
+    """A worktree's git-dir differs from the shared common-dir."""
+    env = {"PATH": "/usr/bin"}
+    with (
+        patch.object(
+            script_setup,
+            "git_output",
+            side_effect=_fake_git_output("/repo/.git/worktrees/wt", "/repo/.git"),
+        ),
+        patch.object(script_setup.subprocess, "run") as mock_run,
+    ):
+        script_setup.install_git_hooks(env)
+    mock_run.assert_not_called()
+
+
+def test_install_git_hooks_missing_prek_raises_system_exit(
+    script_setup: ModuleType,
+) -> None:
+    env = {"PATH": "/usr/bin"}
+    with (
+        patch.object(
+            script_setup,
+            "git_output",
+            side_effect=_fake_git_output("/repo/.git", "/repo/.git"),
+        ),
+        patch.object(script_setup.shutil, "which", return_value=None),
+        patch.object(script_setup.subprocess, "run") as mock_run,
+        pytest.raises(SystemExit, match="prek was not installed"),
+    ):
+        script_setup.install_git_hooks(env)
+    mock_run.assert_not_called()
+
+
+def test_install_git_hooks_happy_path_installs_hook(
+    script_setup: ModuleType, tmp_path: Path
+) -> None:
+    env = {"PATH": "/usr/bin"}
+    common_dir = tmp_path / "repo" / ".git"
+    hooks_dir = common_dir / "hooks"
+    hooks_dir.mkdir(parents=True)
+    source_hook = tmp_path / "post-checkout"
+    source_hook.write_text("#!/bin/sh\necho post-checkout\n")
+
+    with (
+        patch.object(script_setup, "POST_CHECKOUT_HOOK", source_hook),
+        patch.object(
+            script_setup,
+            "git_output",
+            side_effect=_fake_git_output(str(common_dir), str(common_dir)),
+        ),
+        patch.object(script_setup.shutil, "which", return_value="/usr/bin/prek"),
+        patch.object(
+            script_setup.subprocess, "run", return_value=Mock(returncode=0)
+        ) as mock_run,
+    ):
+        script_setup.install_git_hooks(env)
+
+    mock_run.assert_called_once_with(
+        ["/usr/bin/prek", "install", "--overwrite"],
+        cwd=script_setup.ROOT,
+        env=env,
+        check=False,
+    )
+    installed = hooks_dir / "post-checkout"
+    assert installed.read_text() == source_hook.read_text()
+    if os.name != "nt":
+        # Windows has no POSIX permission bits for chmod to set.
+        assert (installed.stat().st_mode & 0o777) == 0o755
+
+
+def test_install_git_hooks_skips_copy_when_hooks_dir_missing(
+    script_setup: ModuleType, tmp_path: Path
+) -> None:
+    """The prek install still runs when the hooks directory does not exist."""
+    env = {"PATH": "/usr/bin"}
+    common_dir = tmp_path / "repo" / ".git"
+    common_dir.mkdir(parents=True)  # no "hooks" subdirectory created
+
+    with (
+        patch.object(
+            script_setup,
+            "git_output",
+            side_effect=_fake_git_output(str(common_dir), str(common_dir)),
+        ),
+        patch.object(script_setup.shutil, "which", return_value="/usr/bin/prek"),
+        patch.object(
+            script_setup.subprocess, "run", return_value=Mock(returncode=0)
+        ) as mock_run,
+    ):
+        script_setup.install_git_hooks(env)
+
+    mock_run.assert_called_once()
+    assert not (common_dir / "hooks").exists()
+
+
+# --- report ------------------------------------------------------------------
+
+
+def test_report_active_state(
+    script_setup: ModuleType, capsys: pytest.CaptureFixture
+) -> None:
+    venv = Path("/opt/esphome-venv")
+    script_setup.report(script_setup.VENV_ACTIVE, venv)
+    out = capsys.readouterr().out
+    assert "Dependencies installed into the active virtual environment:" in out
+    assert str(venv) in out
+    assert "is already active in this shell" in out
+
+
+def test_report_reused_state(
+    script_setup: ModuleType, capsys: pytest.CaptureFixture
+) -> None:
+    script_setup.report(script_setup.VENV_REUSED, script_setup.DEFAULT_VENV)
+    out = capsys.readouterr().out
+    assert "Dependencies updated in the existing ./venv" in out
+
+
+def test_report_created_state(
+    script_setup: ModuleType, capsys: pytest.CaptureFixture
+) -> None:
+    script_setup.report(script_setup.VENV_CREATED, script_setup.DEFAULT_VENV)
+    out = capsys.readouterr().out
+    assert "Virtual environment created at ./venv" in out
+
+
+# --- main --------------------------------------------------------------------
+
+
+def test_main_raises_system_exit_when_python_too_old(
+    script_setup: ModuleType,
+) -> None:
+    with (
+        patch.object(script_setup.sys, "version_info", (3, 11, 5)),
+        pytest.raises(SystemExit, match="ESPHome needs Python 3.12"),
+    ):
+        script_setup.main()
+
+
+def test_main_uses_active_virtual_env(
+    script_setup: ModuleType, tmp_path: Path, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    active_venv = tmp_path / "active-venv"
+    monkeypatch.setenv("VIRTUAL_ENV", str(active_venv))
+    with (
+        patch.object(script_setup, "ROOT", tmp_path),
+        patch.object(script_setup, "create_venv") as mock_create_venv,
+        patch.object(script_setup, "install_dependencies") as mock_install_deps,
+        patch.object(script_setup, "install_git_hooks") as mock_install_hooks,
+        patch.object(script_setup, "report") as mock_report,
+    ):
+        script_setup.main()
+    mock_create_venv.assert_not_called()
+    mock_install_deps.assert_called_once()
+    mock_install_hooks.assert_called_once()
+    mock_report.assert_called_once_with(script_setup.VENV_ACTIVE, active_venv)
+    assert (tmp_path / ".temp").is_dir()
+
+
+def test_main_reuses_existing_venv(
+    script_setup: ModuleType, tmp_path: Path, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    monkeypatch.delenv("VIRTUAL_ENV", raising=False)
+    default_venv = tmp_path / "venv"
+    python_path = script_setup.venv_python(default_venv)
+    python_path.parent.mkdir(parents=True)
+    python_path.touch()
+
+    with (
+        patch.object(script_setup, "ROOT", tmp_path),
+        patch.object(script_setup, "DEFAULT_VENV", default_venv),
+        patch.object(script_setup, "create_venv") as mock_create_venv,
+        patch.object(script_setup, "install_dependencies") as mock_install_deps,
+        patch.object(script_setup, "install_git_hooks") as mock_install_hooks,
+        patch.object(script_setup, "report") as mock_report,
+    ):
+        script_setup.main()
+    mock_create_venv.assert_not_called()
+    mock_install_deps.assert_called_once()
+    mock_install_hooks.assert_called_once()
+    mock_report.assert_called_once_with(script_setup.VENV_REUSED, default_venv)
+    assert (tmp_path / ".temp").is_dir()
+
+
+def test_main_creates_new_venv(
+    script_setup: ModuleType, tmp_path: Path, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    monkeypatch.delenv("VIRTUAL_ENV", raising=False)
+    default_venv = tmp_path / "venv"  # does not exist yet
+
+    with (
+        patch.object(script_setup, "ROOT", tmp_path),
+        patch.object(script_setup, "DEFAULT_VENV", default_venv),
+        patch.object(script_setup, "create_venv") as mock_create_venv,
+        patch.object(script_setup, "install_dependencies") as mock_install_deps,
+        patch.object(script_setup, "install_git_hooks") as mock_install_hooks,
+        patch.object(script_setup, "report") as mock_report,
+    ):
+        script_setup.main()
+    mock_create_venv.assert_called_once_with(default_venv)
+    mock_install_deps.assert_called_once()
+    mock_install_hooks.assert_called_once()
+    mock_report.assert_called_once_with(script_setup.VENV_CREATED, default_venv)
+    assert (tmp_path / ".temp").is_dir()
+
+
+def test_run_as_script_calls_main(tmp_path: Path) -> None:
+    """The __main__ guard runs the whole flow, with every side effect stubbed."""
+    completed = Mock(returncode=0, stdout="")
+    with (
+        patch("subprocess.run", return_value=completed) as mock_run,
+        patch("shutil.which", return_value="/usr/bin/uv"),
+        patch("pathlib.Path.mkdir") as mock_mkdir,
+        patch.dict(os.environ, {"VIRTUAL_ENV": str(tmp_path / "env")}),
+    ):
+        runpy.run_path(str(_SCRIPT), run_name="__main__")
+
+    # The dependency install ran, and git reported no hooks directory to touch.
+    assert mock_run.called
+    mock_mkdir.assert_called_once_with(exist_ok=True)

tests/unit_tests/test_config_validation.py

@@ -1394,6 +1394,35 @@ def test_entity_metadata_visibility_hints() -> None:
     assert web["web_server"].visibility is advanced
 
 
+def test_with_visibility_remarks_keys() -> None:
+    """``with_visibility`` re-marks the named keys, preserving each field's
+    default and validator, without touching the other keys or the input schema.
+    """
+    base = cv.Schema(
+        {
+            cv.Optional("a", default=7): cv.int_,
+            cv.Optional("b", visibility=cv.Visibility.ADVANCED): cv.string,
+        }
+    )
+    promoted = cv.with_visibility(base, cv.Visibility.UI, "a")
+
+    pm = {str(k): k for k in promoted.schema}
+    assert pm["a"].visibility is cv.Visibility.UI  # re-marked
+    assert pm["a"].default() == 7  # default preserved
+    assert pm["b"].visibility is cv.Visibility.ADVANCED  # sibling untouched
+    assert promoted({}) == {"a": 7}  # validator/default still applied
+
+    # The input schema is left untouched (no shared-marker mutation).
+    assert {str(k): k for k in base.schema}["a"].visibility is None
+
+
+def test_with_visibility_unknown_key_raises() -> None:
+    """A key not present in the schema is a typo — fail at build time."""
+    base = cv.Schema({cv.Optional("a"): cv.int_})
+    with pytest.raises(ValueError, match="not in schema"):
+        cv.with_visibility(base, cv.Visibility.UI, "nope")
+
+
 def _wrap_str(value: str) -> ESPHomeDataBase:
     """Wrap a raw string as an ESPHomeDataBase, mimicking a YAML-loaded value."""
     return make_data_base(value)