From 25cebedcfcd0ff7b0fb1d9df81858f984bae9862 Mon Sep 17 00:00:00 2001
From: Rene Guca <45061891+rguca@users.noreply.github.com>
Date: Fri, 19 Dec 2025 21:42:39 +0100
Subject: [PATCH 1/7] [dht] Fix "Falling edge for bit 39 failed!" for Sonoff
 THS01 (#9225)

Co-authored-by: Jonathan Swoboda <154711427+swoboda1337@users.noreply.github.com>
---
 esphome/components/dht/dht.cpp | 38 ++++++++++++++++++----------------
 esphome/components/dht/dht.h   |  8 +++++--
 2 files changed, 26 insertions(+), 20 deletions(-)

diff --git a/esphome/components/dht/dht.cpp b/esphome/components/dht/dht.cpp
index cc0bf55a80..e0abb7c5f0 100644
--- a/esphome/components/dht/dht.cpp
+++ b/esphome/components/dht/dht.cpp
@@ -8,17 +8,20 @@ namespace dht {
 static const char *const TAG = "dht";
 
 void DHT::setup() {
-  this->pin_->digital_write(true);
-  this->pin_->setup();
-  this->pin_->digital_write(true);
+  this->t_pin_->digital_write(true);
+  this->t_pin_->setup();
+#ifdef USE_ESP32
+  this->t_pin_->pin_mode(this->t_pin_->get_flags() | gpio::FLAG_OUTPUT | gpio::FLAG_OPEN_DRAIN);
+#endif
+  this->t_pin_->digital_write(true);
 }
 
 void DHT::dump_config() {
   ESP_LOGCONFIG(TAG, "DHT:");
-  LOG_PIN("  Pin: ", this->pin_);
+  LOG_PIN("  Pin: ", this->t_pin_);
   ESP_LOGCONFIG(TAG, "  %sModel: %s", this->is_auto_detect_ ? "Auto-detected " : "",
                 this->model_ == DHT_MODEL_DHT11 ? "DHT11" : "DHT22 or equivalent");
-  ESP_LOGCONFIG(TAG, "  Internal pull-up: %s", ONOFF(this->pin_->get_flags() & gpio::FLAG_PULLUP));
+  ESP_LOGCONFIG(TAG, "  Internal pull-up: %s", ONOFF(this->t_pin_->get_flags() & gpio::FLAG_PULLUP));
   LOG_UPDATE_INTERVAL(this);
   LOG_SENSOR("  ", "Temperature", this->temperature_sensor_);
   LOG_SENSOR("  ", "Humidity", this->humidity_sensor_);
@@ -72,21 +75,15 @@ bool HOT IRAM_ATTR DHT::read_sensor_(float *temperature, float *humidity, bool r
   int8_t i = 0;
   uint8_t data[5] = {0, 0, 0, 0, 0};
 
-  this->pin_->digital_write(false);
-  this->pin_->pin_mode(gpio::FLAG_OUTPUT);
-  this->pin_->digital_write(false);
+#ifndef USE_ESP32
+  this->pin_.pin_mode(gpio::FLAG_OUTPUT);
+#endif
+  this->pin_.digital_write(false);
 
   if (this->model_ == DHT_MODEL_DHT11) {
     delayMicroseconds(18000);
   } else if (this->model_ == DHT_MODEL_SI7021) {
-#ifdef USE_ESP8266
     delayMicroseconds(500);
-    this->pin_->digital_write(true);
-    delayMicroseconds(40);
-#else
-    delayMicroseconds(400);
-    this->pin_->digital_write(true);
-#endif
   } else if (this->model_ == DHT_MODEL_DHT22_TYPE2) {
     delayMicroseconds(2000);
   } else if (this->model_ == DHT_MODEL_AM2120 || this->model_ == DHT_MODEL_AM2302) {
@@ -94,7 +91,12 @@ bool HOT IRAM_ATTR DHT::read_sensor_(float *temperature, float *humidity, bool r
   } else {
     delayMicroseconds(800);
   }
-  this->pin_->pin_mode(this->pin_->get_flags());
+
+#ifdef USE_ESP32
+  this->pin_.digital_write(true);
+#else
+  this->pin_.pin_mode(this->t_pin_->get_flags());
+#endif
 
   {
     InterruptLock lock;
@@ -110,7 +112,7 @@ bool HOT IRAM_ATTR DHT::read_sensor_(float *temperature, float *humidity, bool r
       uint32_t start_time = micros();
 
       // Wait for rising edge
-      while (!this->pin_->digital_read()) {
+      while (!this->pin_.digital_read()) {
         if (micros() - start_time > 90) {
           if (i < 0) {
             error_code = 1;  // line didn't clear
@@ -127,7 +129,7 @@ bool HOT IRAM_ATTR DHT::read_sensor_(float *temperature, float *humidity, bool r
       uint32_t end_time = start_time;
 
       // Wait for falling edge
-      while (this->pin_->digital_read()) {
+      while (this->pin_.digital_read()) {
         end_time = micros();
         if (end_time - start_time > 90) {
           if (i < 0) {
diff --git a/esphome/components/dht/dht.h b/esphome/components/dht/dht.h
index 327e8a4f5c..9047dd2c96 100644
--- a/esphome/components/dht/dht.h
+++ b/esphome/components/dht/dht.h
@@ -38,7 +38,10 @@ class DHT : public PollingComponent {
    */
   void set_dht_model(DHTModel model);
 
-  void set_pin(InternalGPIOPin *pin) { pin_ = pin; }
+  void set_pin(InternalGPIOPin *pin) {
+    this->t_pin_ = pin;
+    this->pin_ = pin->to_isr();
+  }
   void set_model(DHTModel model) { model_ = model; }
   void set_temperature_sensor(sensor::Sensor *temperature_sensor) { temperature_sensor_ = temperature_sensor; }
   void set_humidity_sensor(sensor::Sensor *humidity_sensor) { humidity_sensor_ = humidity_sensor; }
@@ -54,7 +57,8 @@ class DHT : public PollingComponent {
  protected:
   bool read_sensor_(float *temperature, float *humidity, bool report_errors);
 
-  InternalGPIOPin *pin_;
+  InternalGPIOPin *t_pin_;
+  ISRInternalGPIOPin pin_;
   DHTModel model_{DHT_MODEL_AUTO_DETECT};
   bool is_auto_detect_{false};
   sensor::Sensor *temperature_sensor_{nullptr};

From ebc3d28adeeb57db9291f9c73add09e8516d08e6 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Fri, 19 Dec 2025 11:18:15 -1000
Subject: [PATCH 2/7] [wifi] Replace optional with sentinel values to reduce
 RAM and clarify API (#12446)

---
 esphome/components/wifi/wifi_component.cpp    | 51 ++++++++++---------
 esphome/components/wifi/wifi_component.h      | 24 +++++----
 .../wifi/wifi_component_esp8266.cpp           | 10 ++--
 .../wifi/wifi_component_esp_idf.cpp           | 10 ++--
 .../wifi/wifi_component_libretiny.cpp         |  6 +--
 .../components/wifi/wifi_component_pico_w.cpp |  2 +-
 6 files changed, 55 insertions(+), 48 deletions(-)

diff --git a/esphome/components/wifi/wifi_component.cpp b/esphome/components/wifi/wifi_component.cpp
index 7c5b001be9..242265344d 100644
--- a/esphome/components/wifi/wifi_component.cpp
+++ b/esphome/components/wifi/wifi_component.cpp
@@ -2,6 +2,7 @@
 #ifdef USE_WIFI
 #include <cassert>
 #include <cinttypes>
+#include <cmath>
 
 #ifdef USE_ESP32
 #if (ESP_IDF_VERSION_MAJOR >= 5 && ESP_IDF_VERSION_MINOR >= 1)
@@ -394,7 +395,7 @@ void WiFiComponent::start() {
 
   if (this->has_sta()) {
     this->wifi_sta_pre_setup_();
-    if (this->output_power_.has_value() && !this->wifi_apply_output_power_(*this->output_power_)) {
+    if (!std::isnan(this->output_power_) && !this->wifi_apply_output_power_(this->output_power_)) {
       ESP_LOGV(TAG, "Setting Output Power Option failed");
     }
 
@@ -441,7 +442,7 @@ void WiFiComponent::start() {
 #ifdef USE_WIFI_AP
   } else if (this->has_ap()) {
     this->setup_ap_config_();
-    if (this->output_power_.has_value() && !this->wifi_apply_output_power_(*this->output_power_)) {
+    if (!std::isnan(this->output_power_) && !this->wifi_apply_output_power_(this->output_power_)) {
       ESP_LOGV(TAG, "Setting Output Power Option failed");
     }
 #ifdef USE_CAPTIVE_PORTAL
@@ -713,8 +714,8 @@ WiFiAP WiFiComponent::build_params_for_current_phase_() {
     case WiFiRetryPhase::RETRY_HIDDEN:
       // Hidden network mode: clear BSSID/channel to trigger probe request
       // (both explicit hidden and retry hidden use same behavior)
-      params.set_bssid(optional<bssid_t>{});
-      params.set_channel(optional<uint8_t>{});
+      params.clear_bssid();
+      params.clear_channel();
       break;
 
     case WiFiRetryPhase::SCAN_CONNECTING:
@@ -766,21 +767,20 @@ void WiFiComponent::start_connecting(const WiFiAP &ap) {
   char bssid_s[18];
   int8_t priority = 0;
 
-  if (ap.get_bssid().has_value()) {
-    format_mac_addr_upper(ap.get_bssid().value().data(), bssid_s);
-    priority = this->get_sta_priority(ap.get_bssid().value());
+  if (ap.has_bssid()) {
+    format_mac_addr_upper(ap.get_bssid().data(), bssid_s);
+    priority = this->get_sta_priority(ap.get_bssid());
   }
 
   ESP_LOGI(TAG,
            "Connecting to " LOG_SECRET("'%s'") " " LOG_SECRET("(%s)") " (priority %d, attempt %u/%u in phase %s)...",
-           ap.get_ssid().c_str(), ap.get_bssid().has_value() ? bssid_s : LOG_STR_LITERAL("any"), priority,
-           this->num_retried_ + 1, get_max_retries_for_phase(this->retry_phase_),
-           LOG_STR_ARG(retry_phase_to_log_string(this->retry_phase_)));
+           ap.get_ssid().c_str(), ap.has_bssid() ? bssid_s : LOG_STR_LITERAL("any"), priority, this->num_retried_ + 1,
+           get_max_retries_for_phase(this->retry_phase_), LOG_STR_ARG(retry_phase_to_log_string(this->retry_phase_)));
 
 #ifdef ESPHOME_LOG_HAS_VERBOSE
   ESP_LOGV(TAG, "Connection Params:");
   ESP_LOGV(TAG, "  SSID: '%s'", ap.get_ssid().c_str());
-  if (ap.get_bssid().has_value()) {
+  if (ap.has_bssid()) {
     ESP_LOGV(TAG, "  BSSID: %s", bssid_s);
   } else {
     ESP_LOGV(TAG, "  BSSID: Not Set");
@@ -808,8 +808,8 @@ void WiFiComponent::start_connecting(const WiFiAP &ap) {
 #ifdef USE_WIFI_WPA2_EAP
   }
 #endif
-  if (ap.get_channel().has_value()) {
-    ESP_LOGV(TAG, "  Channel: %u", *ap.get_channel());
+  if (ap.has_channel()) {
+    ESP_LOGV(TAG, "  Channel: %u", ap.get_channel());
   } else {
     ESP_LOGV(TAG, "  Channel not set");
   }
@@ -919,8 +919,8 @@ void WiFiComponent::print_connect_params_() {
                 get_wifi_channel(), wifi_subnet_mask_().str().c_str(), wifi_gateway_ip_().str().c_str(),
                 wifi_dns_ip_(0).str().c_str(), wifi_dns_ip_(1).str().c_str());
 #ifdef ESPHOME_LOG_HAS_VERBOSE
-  if (const WiFiAP *config = this->get_selected_sta_(); config && config->get_bssid().has_value()) {
-    ESP_LOGV(TAG, "  Priority: %d", this->get_sta_priority(*config->get_bssid()));
+  if (const WiFiAP *config = this->get_selected_sta_(); config && config->has_bssid()) {
+    ESP_LOGV(TAG, "  Priority: %d", this->get_sta_priority(config->get_bssid()));
   }
 #endif
 #ifdef USE_WIFI_11KV_SUPPORT
@@ -1514,9 +1514,9 @@ void WiFiComponent::log_and_adjust_priority_for_failed_connect_() {
   if (this->retry_phase_ == WiFiRetryPhase::SCAN_CONNECTING && !this->scan_result_.empty()) {
     // Scan-based phase: always use best result (index 0)
     failed_bssid = this->scan_result_[0].get_bssid();
-  } else if (const WiFiAP *config = this->get_selected_sta_(); config && config->get_bssid()) {
+  } else if (const WiFiAP *config = this->get_selected_sta_(); config && config->has_bssid()) {
     // Config has specific BSSID (fast_connect or user-specified)
-    failed_bssid = *config->get_bssid();
+    failed_bssid = config->get_bssid();
   }
 
   if (!failed_bssid.has_value()) {
@@ -1784,24 +1784,27 @@ void WiFiComponent::save_fast_connect_settings_() {
 #endif
 
 void WiFiAP::set_ssid(const std::string &ssid) { this->ssid_ = ssid; }
-void WiFiAP::set_bssid(bssid_t bssid) { this->bssid_ = bssid; }
-void WiFiAP::set_bssid(optional<bssid_t> bssid) { this->bssid_ = bssid; }
+void WiFiAP::set_bssid(const bssid_t &bssid) { this->bssid_ = bssid; }
+void WiFiAP::clear_bssid() { this->bssid_ = {}; }
 void WiFiAP::set_password(const std::string &password) { this->password_ = password; }
 #ifdef USE_WIFI_WPA2_EAP
 void WiFiAP::set_eap(optional<EAPAuth> eap_auth) { this->eap_ = std::move(eap_auth); }
 #endif
-void WiFiAP::set_channel(optional<uint8_t> channel) { this->channel_ = channel; }
+void WiFiAP::set_channel(uint8_t channel) { this->channel_ = channel; }
+void WiFiAP::clear_channel() { this->channel_ = 0; }
 #ifdef USE_WIFI_MANUAL_IP
 void WiFiAP::set_manual_ip(optional<ManualIP> manual_ip) { this->manual_ip_ = manual_ip; }
 #endif
 void WiFiAP::set_hidden(bool hidden) { this->hidden_ = hidden; }
 const std::string &WiFiAP::get_ssid() const { return this->ssid_; }
-const optional<bssid_t> &WiFiAP::get_bssid() const { return this->bssid_; }
+const bssid_t &WiFiAP::get_bssid() const { return this->bssid_; }
+bool WiFiAP::has_bssid() const { return this->bssid_ != bssid_t{}; }
 const std::string &WiFiAP::get_password() const { return this->password_; }
 #ifdef USE_WIFI_WPA2_EAP
 const optional<EAPAuth> &WiFiAP::get_eap() const { return this->eap_; }
 #endif
-const optional<uint8_t> &WiFiAP::get_channel() const { return this->channel_; }
+uint8_t WiFiAP::get_channel() const { return this->channel_; }
+bool WiFiAP::has_channel() const { return this->channel_ != 0; }
 #ifdef USE_WIFI_MANUAL_IP
 const optional<ManualIP> &WiFiAP::get_manual_ip() const { return this->manual_ip_; }
 #endif
@@ -1829,7 +1832,7 @@ bool WiFiScanResult::matches(const WiFiAP &config) const {
     // network is configured without SSID - match other settings
   }
   // If BSSID configured, only match for correct BSSIDs
-  if (config.get_bssid().has_value() && *config.get_bssid() != this->bssid_)
+  if (config.has_bssid() && config.get_bssid() != this->bssid_)
     return false;
 
 #ifdef USE_WIFI_WPA2_EAP
@@ -1847,7 +1850,7 @@ bool WiFiScanResult::matches(const WiFiAP &config) const {
 #endif
 
   // If channel configured, only match networks on that channel.
-  if (config.get_channel().has_value() && *config.get_channel() != this->channel_) {
+  if (config.has_channel() && config.get_channel() != this->channel_) {
     return false;
   }
   return true;
diff --git a/esphome/components/wifi/wifi_component.h b/esphome/components/wifi/wifi_component.h
index be94e9462b..604efa8a7e 100644
--- a/esphome/components/wifi/wifi_component.h
+++ b/esphome/components/wifi/wifi_component.h
@@ -151,25 +151,28 @@ template<typename T> using wifi_scan_vector_t = FixedVector<T>;
 class WiFiAP {
  public:
   void set_ssid(const std::string &ssid);
-  void set_bssid(bssid_t bssid);
-  void set_bssid(optional<bssid_t> bssid);
+  void set_bssid(const bssid_t &bssid);
+  void clear_bssid();
   void set_password(const std::string &password);
 #ifdef USE_WIFI_WPA2_EAP
   void set_eap(optional<EAPAuth> eap_auth);
 #endif  // USE_WIFI_WPA2_EAP
-  void set_channel(optional<uint8_t> channel);
+  void set_channel(uint8_t channel);
+  void clear_channel();
   void set_priority(int8_t priority) { priority_ = priority; }
 #ifdef USE_WIFI_MANUAL_IP
   void set_manual_ip(optional<ManualIP> manual_ip);
 #endif
   void set_hidden(bool hidden);
   const std::string &get_ssid() const;
-  const optional<bssid_t> &get_bssid() const;
+  const bssid_t &get_bssid() const;
+  bool has_bssid() const;
   const std::string &get_password() const;
 #ifdef USE_WIFI_WPA2_EAP
   const optional<EAPAuth> &get_eap() const;
 #endif  // USE_WIFI_WPA2_EAP
-  const optional<uint8_t> &get_channel() const;
+  uint8_t get_channel() const;
+  bool has_channel() const;
   int8_t get_priority() const { return priority_; }
 #ifdef USE_WIFI_MANUAL_IP
   const optional<ManualIP> &get_manual_ip() const;
@@ -179,16 +182,17 @@ class WiFiAP {
  protected:
   std::string ssid_;
   std::string password_;
-  optional<bssid_t> bssid_;
 #ifdef USE_WIFI_WPA2_EAP
   optional<EAPAuth> eap_;
 #endif  // USE_WIFI_WPA2_EAP
 #ifdef USE_WIFI_MANUAL_IP
   optional<ManualIP> manual_ip_;
 #endif
-  optional<uint8_t> channel_;
-  int8_t priority_{0};
-  bool hidden_{false};
+  // Group small types together to minimize padding
+  bssid_t bssid_{};     // 6 bytes, all zeros = any/not set
+  uint8_t channel_{0};  // 1 byte, 0 = auto/not set
+  int8_t priority_{0};  // 1 byte
+  bool hidden_{false};  // 1 byte (+ 3 bytes end padding to 4-byte align)
 };
 
 class WiFiScanResult {
@@ -590,7 +594,7 @@ class WiFiComponent : public Component {
 #ifdef USE_WIFI_AP
   WiFiAP ap_;
 #endif
-  optional<float> output_power_;
+  float output_power_{NAN};
 #ifdef USE_WIFI_LISTENERS
   std::vector<WiFiIPStateListener *> ip_state_listeners_;
   std::vector<WiFiScanResultsListener *> scan_results_listeners_;
diff --git a/esphome/components/wifi/wifi_component_esp8266.cpp b/esphome/components/wifi/wifi_component_esp8266.cpp
index 3b1a442bdb..1329103f98 100644
--- a/esphome/components/wifi/wifi_component_esp8266.cpp
+++ b/esphome/components/wifi/wifi_component_esp8266.cpp
@@ -257,9 +257,9 @@ bool WiFiComponent::wifi_sta_connect_(const WiFiAP &ap) {
   memcpy(reinterpret_cast<char *>(conf.ssid), ap.get_ssid().c_str(), ap.get_ssid().size());
   memcpy(reinterpret_cast<char *>(conf.password), ap.get_password().c_str(), ap.get_password().size());
 
-  if (ap.get_bssid().has_value()) {
+  if (ap.has_bssid()) {
     conf.bssid_set = 1;
-    memcpy(conf.bssid, ap.get_bssid()->data(), 6);
+    memcpy(conf.bssid, ap.get_bssid().data(), 6);
   } else {
     conf.bssid_set = 0;
   }
@@ -381,8 +381,8 @@ bool WiFiComponent::wifi_sta_connect_(const WiFiAP &ap) {
   }
 #endif /* USE_NETWORK_IPV6 */
 
-  if (ap.get_channel().has_value()) {
-    ret = wifi_set_channel(*ap.get_channel());
+  if (ap.has_channel()) {
+    ret = wifi_set_channel(ap.get_channel());
     if (!ret) {
       ESP_LOGV(TAG, "wifi_set_channel failed");
       return false;
@@ -845,7 +845,7 @@ bool WiFiComponent::wifi_start_ap_(const WiFiAP &ap) {
   }
   memcpy(reinterpret_cast<char *>(conf.ssid), ap.get_ssid().c_str(), ap.get_ssid().size());
   conf.ssid_len = static_cast<uint8>(ap.get_ssid().size());
-  conf.channel = ap.get_channel().value_or(1);
+  conf.channel = ap.has_channel() ? ap.get_channel() : 1;
   conf.ssid_hidden = ap.get_hidden();
   conf.max_connection = 5;
   conf.beacon_interval = 100;
diff --git a/esphome/components/wifi/wifi_component_esp_idf.cpp b/esphome/components/wifi/wifi_component_esp_idf.cpp
index 4a3c40a119..f9e117f468 100644
--- a/esphome/components/wifi/wifi_component_esp_idf.cpp
+++ b/esphome/components/wifi/wifi_component_esp_idf.cpp
@@ -339,14 +339,14 @@ bool WiFiComponent::wifi_sta_connect_(const WiFiAP &ap) {
   conf.sta.rm_enabled = this->rrm_;
 #endif
 
-  if (ap.get_bssid().has_value()) {
+  if (ap.has_bssid()) {
     conf.sta.bssid_set = true;
-    memcpy(conf.sta.bssid, ap.get_bssid()->data(), 6);
+    memcpy(conf.sta.bssid, ap.get_bssid().data(), 6);
   } else {
     conf.sta.bssid_set = false;
   }
-  if (ap.get_channel().has_value()) {
-    conf.sta.channel = *ap.get_channel();
+  if (ap.has_channel()) {
+    conf.sta.channel = ap.get_channel();
     conf.sta.scan_method = WIFI_FAST_SCAN;
   } else {
     conf.sta.scan_method = WIFI_ALL_CHANNEL_SCAN;
@@ -1003,7 +1003,7 @@ bool WiFiComponent::wifi_start_ap_(const WiFiAP &ap) {
     return false;
   }
   memcpy(reinterpret_cast<char *>(conf.ap.ssid), ap.get_ssid().c_str(), ap.get_ssid().size());
-  conf.ap.channel = ap.get_channel().value_or(1);
+  conf.ap.channel = ap.has_channel() ? ap.get_channel() : 1;
   conf.ap.ssid_hidden = ap.get_ssid().size();
   conf.ap.max_connection = 5;
   conf.ap.beacon_interval = 100;
diff --git a/esphome/components/wifi/wifi_component_libretiny.cpp b/esphome/components/wifi/wifi_component_libretiny.cpp
index 36003a6eb4..ffc6b21359 100644
--- a/esphome/components/wifi/wifi_component_libretiny.cpp
+++ b/esphome/components/wifi/wifi_component_libretiny.cpp
@@ -139,8 +139,8 @@ bool WiFiComponent::wifi_sta_connect_(const WiFiAP &ap) {
   s_sta_connecting = true;
 
   WiFiStatus status = WiFi.begin(ap.get_ssid().c_str(), ap.get_password().empty() ? NULL : ap.get_password().c_str(),
-                                 ap.get_channel().has_value() ? *ap.get_channel() : 0,
-                                 ap.get_bssid().has_value() ? ap.get_bssid()->data() : NULL);
+                                 ap.get_channel(),  // 0 = auto
+                                 ap.has_bssid() ? ap.get_bssid().data() : NULL);
   if (status != WL_CONNECTED) {
     ESP_LOGW(TAG, "esp_wifi_connect failed: %d", status);
     return false;
@@ -522,7 +522,7 @@ bool WiFiComponent::wifi_start_ap_(const WiFiAP &ap) {
   yield();
 
   return WiFi.softAP(ap.get_ssid().c_str(), ap.get_password().empty() ? NULL : ap.get_password().c_str(),
-                     ap.get_channel().value_or(1), ap.get_hidden());
+                     ap.has_channel() ? ap.get_channel() : 1, ap.get_hidden());
 }
 
 network::IPAddress WiFiComponent::wifi_soft_ap_ip() { return {WiFi.softAPIP()}; }
diff --git a/esphome/components/wifi/wifi_component_pico_w.cpp b/esphome/components/wifi/wifi_component_pico_w.cpp
index 0228755432..4e763a9e22 100644
--- a/esphome/components/wifi/wifi_component_pico_w.cpp
+++ b/esphome/components/wifi/wifi_component_pico_w.cpp
@@ -192,7 +192,7 @@ bool WiFiComponent::wifi_start_ap_(const WiFiAP &ap) {
   }
 #endif
 
-  WiFi.beginAP(ap.get_ssid().c_str(), ap.get_password().c_str(), ap.get_channel().value_or(1));
+  WiFi.beginAP(ap.get_ssid().c_str(), ap.get_password().c_str(), ap.has_channel() ? ap.get_channel() : 1);
 
   return true;
 }

From 81e91c2a8f05a0192d6c1cda0e1b13cb465312f5 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Fri, 19 Dec 2025 11:18:32 -1000
Subject: [PATCH 3/7] [esp32_ble] Add stack-based UUID formatting to avoid heap
 allocations (#12510)

---
 esphome/components/esp32_ble/ble_uuid.cpp     | 17 +++++++++-------
 esphome/components/esp32_ble/ble_uuid.h       |  5 +++++
 .../esp32_ble_client/ble_characteristic.cpp   |  6 +++++-
 .../esp32_ble_client/ble_client_base.cpp      |  7 +++++--
 .../esp32_ble_client/ble_service.cpp          |  7 +++++--
 .../esp32_ble_server/ble_characteristic.cpp   |  6 +++++-
 .../esp32_ble_server/ble_descriptor.cpp       |  6 +++++-
 .../esp32_ble_server/ble_server.cpp           | 20 +++++++++++++++----
 .../esp32_ble_tracker/esp32_ble_tracker.cpp   | 17 +++++++++++-----
 9 files changed, 68 insertions(+), 23 deletions(-)

diff --git a/esphome/components/esp32_ble/ble_uuid.cpp b/esphome/components/esp32_ble/ble_uuid.cpp
index dcbb285e07..c6b27f3bb9 100644
--- a/esphome/components/esp32_ble/ble_uuid.cpp
+++ b/esphome/components/esp32_ble/ble_uuid.cpp
@@ -143,9 +143,8 @@ bool ESPBTUUID::operator==(const ESPBTUUID &uuid) const {
   return this->as_128bit() == uuid.as_128bit();
 }
 esp_bt_uuid_t ESPBTUUID::get_uuid() const { return this->uuid_; }
-std::string ESPBTUUID::to_string() const {
-  char buf[40];  // Enough for 128-bit UUID with dashes
-  char *pos = buf;
+void ESPBTUUID::to_str(std::span<char, UUID_STR_LEN> output) const {
+  char *pos = output.data();
 
   switch (this->uuid_.len) {
     case ESP_UUID_LEN_16:
@@ -156,7 +155,7 @@ std::string ESPBTUUID::to_string() const {
       *pos++ = format_hex_pretty_char((this->uuid_.uuid.uuid16 >> 4) & 0x0F);
       *pos++ = format_hex_pretty_char(this->uuid_.uuid.uuid16 & 0x0F);
       *pos = '\0';
-      return std::string(buf);
+      return;
 
     case ESP_UUID_LEN_32:
       *pos++ = '0';
@@ -165,7 +164,7 @@ std::string ESPBTUUID::to_string() const {
         *pos++ = format_hex_pretty_char((this->uuid_.uuid.uuid32 >> shift) & 0x0F);
       }
       *pos = '\0';
-      return std::string(buf);
+      return;
 
     default:
     case ESP_UUID_LEN_128:
@@ -179,9 +178,13 @@ std::string ESPBTUUID::to_string() const {
         }
       }
       *pos = '\0';
-      return std::string(buf);
+      return;
   }
-  return "";
+}
+std::string ESPBTUUID::to_string() const {
+  char buf[UUID_STR_LEN];
+  this->to_str(buf);
+  return std::string(buf);
 }
 
 }  // namespace esphome::esp32_ble
diff --git a/esphome/components/esp32_ble/ble_uuid.h b/esphome/components/esp32_ble/ble_uuid.h
index 4cf2d10abd..ed561d70e4 100644
--- a/esphome/components/esp32_ble/ble_uuid.h
+++ b/esphome/components/esp32_ble/ble_uuid.h
@@ -7,11 +7,15 @@
 #ifdef USE_ESP32
 #ifdef USE_ESP32_BLE_UUID
 
+#include <span>
 #include <string>
 #include <esp_bt_defs.h>
 
 namespace esphome::esp32_ble {
 
+/// Buffer size for UUID string: "XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX\0"
+static constexpr size_t UUID_STR_LEN = 37;
+
 class ESPBTUUID {
  public:
   ESPBTUUID();
@@ -37,6 +41,7 @@ class ESPBTUUID {
   esp_bt_uuid_t get_uuid() const;
 
   std::string to_string() const;
+  void to_str(std::span<char, UUID_STR_LEN> output) const;
 
  protected:
   esp_bt_uuid_t uuid_;
diff --git a/esphome/components/esp32_ble_client/ble_characteristic.cpp b/esphome/components/esp32_ble_client/ble_characteristic.cpp
index e0d0174c57..e830702f11 100644
--- a/esphome/components/esp32_ble_client/ble_characteristic.cpp
+++ b/esphome/components/esp32_ble_client/ble_characteristic.cpp
@@ -50,8 +50,12 @@ void BLECharacteristic::parse_descriptors() {
     desc->handle = result.handle;
     desc->characteristic = this;
     this->descriptors.push_back(desc);
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+    char uuid_buf[espbt::UUID_STR_LEN];
+    desc->uuid.to_str(uuid_buf);
     ESP_LOGV(TAG, "[%d] [%s]    descriptor %s, handle 0x%x", this->service->client->get_connection_index(),
-             this->service->client->address_str(), desc->uuid.to_string().c_str(), desc->handle);
+             this->service->client->address_str(), uuid_buf, desc->handle);
+#endif
     offset++;
   }
 }
diff --git a/esphome/components/esp32_ble_client/ble_client_base.cpp b/esphome/components/esp32_ble_client/ble_client_base.cpp
index a09390c747..8017b577f4 100644
--- a/esphome/components/esp32_ble_client/ble_client_base.cpp
+++ b/esphome/components/esp32_ble_client/ble_client_base.cpp
@@ -411,12 +411,15 @@ bool BLEClientBase::gattc_event_handler(esp_gattc_cb_event_t event, esp_gatt_if_
         this->update_conn_params_(MEDIUM_MIN_CONN_INTERVAL, MEDIUM_MAX_CONN_INTERVAL, 0, MEDIUM_CONN_TIMEOUT, "medium");
       } else if (this->connection_type_ != espbt::ConnectionType::V3_WITH_CACHE) {
 #ifdef USE_ESP32_BLE_DEVICE
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
         for (auto &svc : this->services_) {
-          ESP_LOGV(TAG, "[%d] [%s] Service UUID: %s", this->connection_index_, this->address_str_,
-                   svc->uuid.to_string().c_str());
+          char uuid_buf[espbt::UUID_STR_LEN];
+          svc->uuid.to_str(uuid_buf);
+          ESP_LOGV(TAG, "[%d] [%s] Service UUID: %s", this->connection_index_, this->address_str_, uuid_buf);
           ESP_LOGV(TAG, "[%d] [%s]  start_handle: 0x%x  end_handle: 0x%x", this->connection_index_, this->address_str_,
                    svc->start_handle, svc->end_handle);
         }
+#endif
 #endif
       }
       ESP_LOGI(TAG, "[%d] [%s] Service discovery complete", this->connection_index_, this->address_str_);
diff --git a/esphome/components/esp32_ble_client/ble_service.cpp b/esphome/components/esp32_ble_client/ble_service.cpp
index deaaa3de02..695f468c5b 100644
--- a/esphome/components/esp32_ble_client/ble_service.cpp
+++ b/esphome/components/esp32_ble_client/ble_service.cpp
@@ -64,9 +64,12 @@ void BLEService::parse_characteristics() {
     characteristic->handle = result.char_handle;
     characteristic->service = this;
     this->characteristics.push_back(characteristic);
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+    char uuid_buf[espbt::UUID_STR_LEN];
+    characteristic->uuid.to_str(uuid_buf);
     ESP_LOGV(TAG, "[%d] [%s]  characteristic %s, handle 0x%x, properties 0x%x", this->client->get_connection_index(),
-             this->client->address_str(), characteristic->uuid.to_string().c_str(), characteristic->handle,
-             characteristic->properties);
+             this->client->address_str(), uuid_buf, characteristic->handle, characteristic->properties);
+#endif
     offset++;
   }
 }
diff --git a/esphome/components/esp32_ble_server/ble_characteristic.cpp b/esphome/components/esp32_ble_server/ble_characteristic.cpp
index 7627a58338..0482848ea0 100644
--- a/esphome/components/esp32_ble_server/ble_characteristic.cpp
+++ b/esphome/components/esp32_ble_server/ble_characteristic.cpp
@@ -109,7 +109,11 @@ void BLECharacteristic::do_create(BLEService *service) {
   esp_attr_control_t control;
   control.auto_rsp = ESP_GATT_RSP_BY_APP;
 
-  ESP_LOGV(TAG, "Creating characteristic - %s", this->uuid_.to_string().c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+  char uuid_buf[esp32_ble::UUID_STR_LEN];
+  this->uuid_.to_str(uuid_buf);
+  ESP_LOGV(TAG, "Creating characteristic - %s", uuid_buf);
+#endif
 
   esp_bt_uuid_t uuid = this->uuid_.get_uuid();
   esp_err_t err = esp_ble_gatts_add_char(service->get_handle(), &uuid, static_cast<esp_gatt_perm_t>(this->permissions_),
diff --git a/esphome/components/esp32_ble_server/ble_descriptor.cpp b/esphome/components/esp32_ble_server/ble_descriptor.cpp
index 2d053c09bd..4ffca7312b 100644
--- a/esphome/components/esp32_ble_server/ble_descriptor.cpp
+++ b/esphome/components/esp32_ble_server/ble_descriptor.cpp
@@ -34,7 +34,11 @@ void BLEDescriptor::do_create(BLECharacteristic *characteristic) {
   esp_attr_control_t control;
   control.auto_rsp = ESP_GATT_AUTO_RSP;
 
-  ESP_LOGV(TAG, "Creating descriptor - %s", this->uuid_.to_string().c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+  char uuid_buf[esp32_ble::UUID_STR_LEN];
+  this->uuid_.to_str(uuid_buf);
+  ESP_LOGV(TAG, "Creating descriptor - %s", uuid_buf);
+#endif
   esp_bt_uuid_t uuid = this->uuid_.get_uuid();
   esp_err_t err = esp_ble_gatts_add_char_descr(this->characteristic_->get_service()->get_handle(), &uuid,
                                                this->permissions_, &this->value_, &control);
diff --git a/esphome/components/esp32_ble_server/ble_server.cpp b/esphome/components/esp32_ble_server/ble_server.cpp
index 0e58224a5a..2c13a8ac36 100644
--- a/esphome/components/esp32_ble_server/ble_server.cpp
+++ b/esphome/components/esp32_ble_server/ble_server.cpp
@@ -106,7 +106,11 @@ void BLEServer::restart_advertising_() {
 }
 
 BLEService *BLEServer::create_service(ESPBTUUID uuid, bool advertise, uint16_t num_handles) {
-  ESP_LOGV(TAG, "Creating BLE service - %s", uuid.to_string().c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+  char uuid_buf[esp32_ble::UUID_STR_LEN];
+  uuid.to_str(uuid_buf);
+  ESP_LOGV(TAG, "Creating BLE service - %s", uuid_buf);
+#endif
   // Calculate the inst_id for the service
   uint8_t inst_id = 0;
   for (; inst_id < 0xFF; inst_id++) {
@@ -115,7 +119,9 @@ BLEService *BLEServer::create_service(ESPBTUUID uuid, bool advertise, uint16_t n
     }
   }
   if (inst_id == 0xFF) {
-    ESP_LOGW(TAG, "Could not create BLE service %s, too many instances", uuid.to_string().c_str());
+    char warn_uuid_buf[esp32_ble::UUID_STR_LEN];
+    uuid.to_str(warn_uuid_buf);
+    ESP_LOGW(TAG, "Could not create BLE service %s, too many instances", warn_uuid_buf);
     return nullptr;
   }
   BLEService *service =  // NOLINT(cppcoreguidelines-owning-memory)
@@ -128,7 +134,11 @@ BLEService *BLEServer::create_service(ESPBTUUID uuid, bool advertise, uint16_t n
 }
 
 void BLEServer::remove_service(ESPBTUUID uuid, uint8_t inst_id) {
-  ESP_LOGV(TAG, "Removing BLE service - %s %d", uuid.to_string().c_str(), inst_id);
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+  char uuid_buf[esp32_ble::UUID_STR_LEN];
+  uuid.to_str(uuid_buf);
+  ESP_LOGV(TAG, "Removing BLE service - %s %d", uuid_buf, inst_id);
+#endif
   for (auto it = this->services_.begin(); it != this->services_.end(); ++it) {
     if (it->uuid == uuid && it->inst_id == inst_id) {
       it->service->do_delete();
@@ -137,7 +147,9 @@ void BLEServer::remove_service(ESPBTUUID uuid, uint8_t inst_id) {
       return;
     }
   }
-  ESP_LOGW(TAG, "BLE service %s %d does not exist", uuid.to_string().c_str(), inst_id);
+  char warn_uuid_buf[esp32_ble::UUID_STR_LEN];
+  uuid.to_str(warn_uuid_buf);
+  ESP_LOGW(TAG, "BLE service %s %d does not exist", warn_uuid_buf, inst_id);
 }
 
 BLEService *BLEServer::get_service(ESPBTUUID uuid, uint8_t inst_id) {
diff --git a/esphome/components/esp32_ble_tracker/esp32_ble_tracker.cpp b/esphome/components/esp32_ble_tracker/esp32_ble_tracker.cpp
index 45e343c0d2..cb83eb5a0d 100644
--- a/esphome/components/esp32_ble_tracker/esp32_ble_tracker.cpp
+++ b/esphome/components/esp32_ble_tracker/esp32_ble_tracker.cpp
@@ -438,24 +438,31 @@ void ESPBTDevice::parse_scan_rst(const BLEScanResult &scan_result) {
     ESP_LOGVV(TAG, "  Ad Flag: %u", *this->ad_flag_);
   }
   for (auto &uuid : this->service_uuids_) {
-    ESP_LOGVV(TAG, "  Service UUID: %s", uuid.to_string().c_str());
+    char uuid_buf[esp32_ble::UUID_STR_LEN];
+    uuid.to_str(uuid_buf);
+    ESP_LOGVV(TAG, "  Service UUID: %s", uuid_buf);
   }
   for (auto &data : this->manufacturer_datas_) {
     auto ibeacon = ESPBLEiBeacon::from_manufacturer_data(data);
     if (ibeacon.has_value()) {
       ESP_LOGVV(TAG, "  Manufacturer iBeacon:");
-      ESP_LOGVV(TAG, "    UUID: %s", ibeacon.value().get_uuid().to_string().c_str());
+      char uuid_buf[esp32_ble::UUID_STR_LEN];
+      ibeacon.value().get_uuid().to_str(uuid_buf);
+      ESP_LOGVV(TAG, "    UUID: %s", uuid_buf);
       ESP_LOGVV(TAG, "    Major: %u", ibeacon.value().get_major());
       ESP_LOGVV(TAG, "    Minor: %u", ibeacon.value().get_minor());
       ESP_LOGVV(TAG, "    TXPower: %d", ibeacon.value().get_signal_power());
     } else {
-      ESP_LOGVV(TAG, "  Manufacturer ID: %s, data: %s", data.uuid.to_string().c_str(),
-                format_hex_pretty(data.data).c_str());
+      char uuid_buf[esp32_ble::UUID_STR_LEN];
+      data.uuid.to_str(uuid_buf);
+      ESP_LOGVV(TAG, "  Manufacturer ID: %s, data: %s", uuid_buf, format_hex_pretty(data.data).c_str());
     }
   }
   for (auto &data : this->service_datas_) {
     ESP_LOGVV(TAG, "  Service data:");
-    ESP_LOGVV(TAG, "    UUID: %s", data.uuid.to_string().c_str());
+    char uuid_buf[esp32_ble::UUID_STR_LEN];
+    data.uuid.to_str(uuid_buf);
+    ESP_LOGVV(TAG, "    UUID: %s", uuid_buf);
     ESP_LOGVV(TAG, "    Data: %s", format_hex_pretty(data.data).c_str());
   }
 

From 940afdbb12e212299edc1ad67481ef9a6d5f568e Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Fri, 19 Dec 2025 11:18:50 -1000
Subject: [PATCH 4/7] [climate] Add zero-copy support for API custom fan mode
 and preset commands (#12402)

---
 esphome/components/api/api.proto            |  4 +-
 esphome/components/api/api_connection.cpp   |  4 +-
 esphome/components/api/api_pb2.cpp          | 14 +++++--
 esphome/components/api/api_pb2.h            |  8 ++--
 esphome/components/api/api_pb2_dump.cpp     |  8 +++-
 esphome/components/climate/climate.cpp      | 45 +++++++++++++++------
 esphome/components/climate/climate.h        |  6 +++
 esphome/components/climate/climate_traits.h | 22 +++++++---
 8 files changed, 80 insertions(+), 31 deletions(-)

diff --git a/esphome/components/api/api.proto b/esphome/components/api/api.proto
index 50af5061c0..dd8320bebb 100644
--- a/esphome/components/api/api.proto
+++ b/esphome/components/api/api.proto
@@ -1091,11 +1091,11 @@ message ClimateCommandRequest {
   bool has_swing_mode = 14;
   ClimateSwingMode swing_mode = 15;
   bool has_custom_fan_mode = 16;
-  string custom_fan_mode = 17;
+  string custom_fan_mode = 17 [(pointer_to_buffer) = true];
   bool has_preset = 18;
   ClimatePreset preset = 19;
   bool has_custom_preset = 20;
-  string custom_preset = 21;
+  string custom_preset = 21 [(pointer_to_buffer) = true];
   bool has_target_humidity = 22;
   float target_humidity = 23;
   uint32 device_id = 24 [(field_ifdef) = "USE_DEVICES"];
diff --git a/esphome/components/api/api_connection.cpp b/esphome/components/api/api_connection.cpp
index 85f4566f3c..686fdcba41 100644
--- a/esphome/components/api/api_connection.cpp
+++ b/esphome/components/api/api_connection.cpp
@@ -712,11 +712,11 @@ void APIConnection::climate_command(const ClimateCommandRequest &msg) {
   if (msg.has_fan_mode)
     call.set_fan_mode(static_cast<climate::ClimateFanMode>(msg.fan_mode));
   if (msg.has_custom_fan_mode)
-    call.set_fan_mode(msg.custom_fan_mode);
+    call.set_fan_mode(reinterpret_cast<const char *>(msg.custom_fan_mode), msg.custom_fan_mode_len);
   if (msg.has_preset)
     call.set_preset(static_cast<climate::ClimatePreset>(msg.preset));
   if (msg.has_custom_preset)
-    call.set_preset(msg.custom_preset);
+    call.set_preset(reinterpret_cast<const char *>(msg.custom_preset), msg.custom_preset_len);
   if (msg.has_swing_mode)
     call.set_swing_mode(static_cast<climate::ClimateSwingMode>(msg.swing_mode));
   call.perform();
diff --git a/esphome/components/api/api_pb2.cpp b/esphome/components/api/api_pb2.cpp
index 52f4b495e9..211f856e3b 100644
--- a/esphome/components/api/api_pb2.cpp
+++ b/esphome/components/api/api_pb2.cpp
@@ -1392,12 +1392,18 @@ bool ClimateCommandRequest::decode_varint(uint32_t field_id, ProtoVarInt value)
 }
 bool ClimateCommandRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
-    case 17:
-      this->custom_fan_mode = value.as_string();
+    case 17: {
+      // Use raw data directly to avoid allocation
+      this->custom_fan_mode = value.data();
+      this->custom_fan_mode_len = value.size();
       break;
-    case 21:
-      this->custom_preset = value.as_string();
+    }
+    case 21: {
+      // Use raw data directly to avoid allocation
+      this->custom_preset = value.data();
+      this->custom_preset_len = value.size();
       break;
+    }
     default:
       return false;
   }
diff --git a/esphome/components/api/api_pb2.h b/esphome/components/api/api_pb2.h
index f23a62fc3c..4e10c63881 100644
--- a/esphome/components/api/api_pb2.h
+++ b/esphome/components/api/api_pb2.h
@@ -1475,7 +1475,7 @@ class ClimateStateResponse final : public StateResponseProtoMessage {
 class ClimateCommandRequest final : public CommandProtoMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 48;
-  static constexpr uint8_t ESTIMATED_SIZE = 84;
+  static constexpr uint8_t ESTIMATED_SIZE = 104;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "climate_command_request"; }
 #endif
@@ -1492,11 +1492,13 @@ class ClimateCommandRequest final : public CommandProtoMessage {
   bool has_swing_mode{false};
   enums::ClimateSwingMode swing_mode{};
   bool has_custom_fan_mode{false};
-  std::string custom_fan_mode{};
+  const uint8_t *custom_fan_mode{nullptr};
+  uint16_t custom_fan_mode_len{0};
   bool has_preset{false};
   enums::ClimatePreset preset{};
   bool has_custom_preset{false};
-  std::string custom_preset{};
+  const uint8_t *custom_preset{nullptr};
+  uint16_t custom_preset_len{0};
   bool has_target_humidity{false};
   float target_humidity{0.0f};
 #ifdef HAS_PROTO_MESSAGE_DUMP
diff --git a/esphome/components/api/api_pb2_dump.cpp b/esphome/components/api/api_pb2_dump.cpp
index 5e271f41cb..90e8e75c93 100644
--- a/esphome/components/api/api_pb2_dump.cpp
+++ b/esphome/components/api/api_pb2_dump.cpp
@@ -1374,11 +1374,15 @@ void ClimateCommandRequest::dump_to(std::string &out) const {
   dump_field(out, "has_swing_mode", this->has_swing_mode);
   dump_field(out, "swing_mode", static_cast<enums::ClimateSwingMode>(this->swing_mode));
   dump_field(out, "has_custom_fan_mode", this->has_custom_fan_mode);
-  dump_field(out, "custom_fan_mode", this->custom_fan_mode);
+  out.append("  custom_fan_mode: ");
+  out.append(format_hex_pretty(this->custom_fan_mode, this->custom_fan_mode_len));
+  out.append("\n");
   dump_field(out, "has_preset", this->has_preset);
   dump_field(out, "preset", static_cast<enums::ClimatePreset>(this->preset));
   dump_field(out, "has_custom_preset", this->has_custom_preset);
-  dump_field(out, "custom_preset", this->custom_preset);
+  out.append("  custom_preset: ");
+  out.append(format_hex_pretty(this->custom_preset, this->custom_preset_len));
+  out.append("\n");
   dump_field(out, "has_target_humidity", this->has_target_humidity);
   dump_field(out, "target_humidity", this->target_humidity);
 #ifdef USE_DEVICES
diff --git a/esphome/components/climate/climate.cpp b/esphome/components/climate/climate.cpp
index 3bc20a17c6..229862ce01 100644
--- a/esphome/components/climate/climate.cpp
+++ b/esphome/components/climate/climate.cpp
@@ -2,6 +2,7 @@
 #include "esphome/core/defines.h"
 #include "esphome/core/controller_registry.h"
 #include "esphome/core/macros.h"
+#include <strings.h>
 
 namespace esphome::climate {
 
@@ -190,24 +191,30 @@ ClimateCall &ClimateCall::set_fan_mode(ClimateFanMode fan_mode) {
 }
 
 ClimateCall &ClimateCall::set_fan_mode(const char *custom_fan_mode) {
+  return this->set_fan_mode(custom_fan_mode, strlen(custom_fan_mode));
+}
+
+ClimateCall &ClimateCall::set_fan_mode(const std::string &fan_mode) {
+  return this->set_fan_mode(fan_mode.data(), fan_mode.size());
+}
+
+ClimateCall &ClimateCall::set_fan_mode(const char *custom_fan_mode, size_t len) {
   // Check if it's a standard enum mode first
   for (const auto &mode_entry : CLIMATE_FAN_MODES_BY_STR) {
-    if (str_equals_case_insensitive(custom_fan_mode, mode_entry.str)) {
+    if (strncasecmp(custom_fan_mode, mode_entry.str, len) == 0 && mode_entry.str[len] == '\0') {
       return this->set_fan_mode(static_cast<ClimateFanMode>(mode_entry.value));
     }
   }
   // Find the matching pointer from parent climate device
-  if (const char *mode_ptr = this->parent_->find_custom_fan_mode_(custom_fan_mode)) {
+  if (const char *mode_ptr = this->parent_->find_custom_fan_mode_(custom_fan_mode, len)) {
     this->custom_fan_mode_ = mode_ptr;
     this->fan_mode_.reset();
     return *this;
   }
-  ESP_LOGW(TAG, "'%s' - Unrecognized fan mode %s", this->parent_->get_name().c_str(), custom_fan_mode);
+  ESP_LOGW(TAG, "'%s' - Unrecognized fan mode %.*s", this->parent_->get_name().c_str(), (int) len, custom_fan_mode);
   return *this;
 }
 
-ClimateCall &ClimateCall::set_fan_mode(const std::string &fan_mode) { return this->set_fan_mode(fan_mode.c_str()); }
-
 ClimateCall &ClimateCall::set_fan_mode(optional<std::string> fan_mode) {
   if (fan_mode.has_value()) {
     this->set_fan_mode(fan_mode.value());
@@ -222,24 +229,30 @@ ClimateCall &ClimateCall::set_preset(ClimatePreset preset) {
 }
 
 ClimateCall &ClimateCall::set_preset(const char *custom_preset) {
+  return this->set_preset(custom_preset, strlen(custom_preset));
+}
+
+ClimateCall &ClimateCall::set_preset(const std::string &preset) {
+  return this->set_preset(preset.data(), preset.size());
+}
+
+ClimateCall &ClimateCall::set_preset(const char *custom_preset, size_t len) {
   // Check if it's a standard enum preset first
   for (const auto &preset_entry : CLIMATE_PRESETS_BY_STR) {
-    if (str_equals_case_insensitive(custom_preset, preset_entry.str)) {
+    if (strncasecmp(custom_preset, preset_entry.str, len) == 0 && preset_entry.str[len] == '\0') {
       return this->set_preset(static_cast<ClimatePreset>(preset_entry.value));
     }
   }
   // Find the matching pointer from parent climate device
-  if (const char *preset_ptr = this->parent_->find_custom_preset_(custom_preset)) {
+  if (const char *preset_ptr = this->parent_->find_custom_preset_(custom_preset, len)) {
     this->custom_preset_ = preset_ptr;
     this->preset_.reset();
     return *this;
   }
-  ESP_LOGW(TAG, "'%s' - Unrecognized preset %s", this->parent_->get_name().c_str(), custom_preset);
+  ESP_LOGW(TAG, "'%s' - Unrecognized preset %.*s", this->parent_->get_name().c_str(), (int) len, custom_preset);
   return *this;
 }
 
-ClimateCall &ClimateCall::set_preset(const std::string &preset) { return this->set_preset(preset.c_str()); }
-
 ClimateCall &ClimateCall::set_preset(optional<std::string> preset) {
   if (preset.has_value()) {
     this->set_preset(preset.value());
@@ -688,11 +701,19 @@ bool Climate::set_custom_preset_(const char *preset) {
 void Climate::clear_custom_preset_() { this->custom_preset_ = nullptr; }
 
 const char *Climate::find_custom_fan_mode_(const char *custom_fan_mode) {
-  return this->get_traits().find_custom_fan_mode_(custom_fan_mode);
+  return this->find_custom_fan_mode_(custom_fan_mode, strlen(custom_fan_mode));
+}
+
+const char *Climate::find_custom_fan_mode_(const char *custom_fan_mode, size_t len) {
+  return this->get_traits().find_custom_fan_mode_(custom_fan_mode, len);
 }
 
 const char *Climate::find_custom_preset_(const char *custom_preset) {
-  return this->get_traits().find_custom_preset_(custom_preset);
+  return this->find_custom_preset_(custom_preset, strlen(custom_preset));
+}
+
+const char *Climate::find_custom_preset_(const char *custom_preset, size_t len) {
+  return this->get_traits().find_custom_preset_(custom_preset, len);
 }
 
 void Climate::dump_traits_(const char *tag) {
diff --git a/esphome/components/climate/climate.h b/esphome/components/climate/climate.h
index 82df4b815f..0bae28df5a 100644
--- a/esphome/components/climate/climate.h
+++ b/esphome/components/climate/climate.h
@@ -78,6 +78,8 @@ class ClimateCall {
   ClimateCall &set_fan_mode(optional<std::string> fan_mode);
   /// Set the custom fan mode of the climate device.
   ClimateCall &set_fan_mode(const char *custom_fan_mode);
+  /// Set the custom fan mode of the climate device (zero-copy API path).
+  ClimateCall &set_fan_mode(const char *custom_fan_mode, size_t len);
   /// Set the swing mode of the climate device.
   ClimateCall &set_swing_mode(ClimateSwingMode swing_mode);
   /// Set the swing mode of the climate device.
@@ -94,6 +96,8 @@ class ClimateCall {
   ClimateCall &set_preset(optional<std::string> preset);
   /// Set the custom preset of the climate device.
   ClimateCall &set_preset(const char *custom_preset);
+  /// Set the custom preset of the climate device (zero-copy API path).
+  ClimateCall &set_preset(const char *custom_preset, size_t len);
 
   void perform();
 
@@ -290,9 +294,11 @@ class Climate : public EntityBase {
 
   /// Find and return the matching custom fan mode pointer from traits, or nullptr if not found.
   const char *find_custom_fan_mode_(const char *custom_fan_mode);
+  const char *find_custom_fan_mode_(const char *custom_fan_mode, size_t len);
 
   /// Find and return the matching custom preset pointer from traits, or nullptr if not found.
   const char *find_custom_preset_(const char *custom_preset);
+  const char *find_custom_preset_(const char *custom_preset, size_t len);
 
   /** Get the default traits of this climate device.
    *
diff --git a/esphome/components/climate/climate_traits.h b/esphome/components/climate/climate_traits.h
index d358293475..80ef0854d5 100644
--- a/esphome/components/climate/climate_traits.h
+++ b/esphome/components/climate/climate_traits.h
@@ -20,18 +20,22 @@ using ClimatePresetMask = FiniteSetMask<ClimatePreset, DefaultBitPolicy<ClimateP
 
 // Lightweight linear search for small vectors (1-20 items) of const char* pointers
 // Avoids std::find template overhead
-inline bool vector_contains(const std::vector<const char *> &vec, const char *value) {
+inline bool vector_contains(const std::vector<const char *> &vec, const char *value, size_t len) {
   for (const char *item : vec) {
-    if (strcmp(item, value) == 0)
+    if (strncmp(item, value, len) == 0 && item[len] == '\0')
       return true;
   }
   return false;
 }
 
+inline bool vector_contains(const std::vector<const char *> &vec, const char *value) {
+  return vector_contains(vec, value, strlen(value));
+}
+
 // Find and return matching pointer from vector, or nullptr if not found
-inline const char *vector_find(const std::vector<const char *> &vec, const char *value) {
+inline const char *vector_find(const std::vector<const char *> &vec, const char *value, size_t len) {
   for (const char *item : vec) {
-    if (strcmp(item, value) == 0)
+    if (strncmp(item, value, len) == 0 && item[len] == '\0')
       return item;
   }
   return nullptr;
@@ -257,13 +261,19 @@ class ClimateTraits {
   /// Find and return the matching custom fan mode pointer from supported modes, or nullptr if not found
   /// This is protected as it's an implementation detail - use Climate::find_custom_fan_mode_() instead
   const char *find_custom_fan_mode_(const char *custom_fan_mode) const {
-    return vector_find(this->supported_custom_fan_modes_, custom_fan_mode);
+    return this->find_custom_fan_mode_(custom_fan_mode, strlen(custom_fan_mode));
+  }
+  const char *find_custom_fan_mode_(const char *custom_fan_mode, size_t len) const {
+    return vector_find(this->supported_custom_fan_modes_, custom_fan_mode, len);
   }
 
   /// Find and return the matching custom preset pointer from supported presets, or nullptr if not found
   /// This is protected as it's an implementation detail - use Climate::find_custom_preset_() instead
   const char *find_custom_preset_(const char *custom_preset) const {
-    return vector_find(this->supported_custom_presets_, custom_preset);
+    return this->find_custom_preset_(custom_preset, strlen(custom_preset));
+  }
+  const char *find_custom_preset_(const char *custom_preset, size_t len) const {
+    return vector_find(this->supported_custom_presets_, custom_preset, len);
   }
 
   uint32_t feature_flags_{0};

From 988b888c6308d3b819918a6ec50a31aca76b8e43 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Fri, 19 Dec 2025 11:19:07 -1000
Subject: [PATCH 5/7] [ota] Replace std::function callbacks with listener
 interface (#12167)

---
 .../components/esp32_ble_tracker/__init__.py  |  4 +-
 .../esp32_ble_tracker/esp32_ble_tracker.cpp   | 27 +++---
 .../esp32_ble_tracker/esp32_ble_tracker.h     | 11 +++
 .../components/esphome/ota/ota_esphome.cpp    | 20 ++--
 .../http_request/ota/ota_http_request.cpp     | 22 ++---
 .../http_request/ota/ota_http_request.h       |  1 -
 .../http_request/update/__init__.py           |  4 +-
 .../update/http_request_update.cpp            | 26 +++---
 .../http_request/update/http_request_update.h |  4 +-
 .../components/micro_wake_word/__init__.py    |  4 +-
 .../micro_wake_word/micro_wake_word.cpp       | 21 +++--
 .../micro_wake_word/micro_wake_word.h         | 16 +++-
 esphome/components/ota/__init__.py            | 22 ++++-
 esphome/components/ota/automation.h           | 92 +++++++++----------
 esphome/components/ota/ota_backend.cpp        |  9 +-
 esphome/components/ota/ota_backend.h          | 91 ++++++++++--------
 .../speaker/media_player/__init__.py          |  4 +-
 .../media_player/speaker_media_player.cpp     | 42 +++++----
 .../media_player/speaker_media_player.h       | 18 +++-
 .../web_server/ota/ota_web_server.cpp         | 40 ++++----
 esphome/core/defines.h                        |  2 +-
 21 files changed, 274 insertions(+), 206 deletions(-)

diff --git a/esphome/components/esp32_ble_tracker/__init__.py b/esphome/components/esp32_ble_tracker/__init__.py
index 4e25434aad..37e74672ed 100644
--- a/esphome/components/esp32_ble_tracker/__init__.py
+++ b/esphome/components/esp32_ble_tracker/__init__.py
@@ -5,7 +5,7 @@ import logging
 
 from esphome import automation
 import esphome.codegen as cg
-from esphome.components import esp32_ble
+from esphome.components import esp32_ble, ota
 from esphome.components.esp32 import add_idf_sdkconfig_option
 from esphome.components.esp32_ble import (
     IDF_MAX_CONNECTIONS,
@@ -328,7 +328,7 @@ async def to_code(config):
     # Note: CONFIG_BT_ACL_CONNECTIONS and CONFIG_BTDM_CTRL_BLE_MAX_CONN are now
     # configured in esp32_ble component based on max_connections setting
 
-    cg.add_define("USE_OTA_STATE_CALLBACK")  # To be notified when an OTA update starts
+    ota.request_ota_state_listeners()  # To be notified when an OTA update starts
     cg.add_define("USE_ESP32_BLE_CLIENT")
 
     CORE.add_job(_add_ble_features)
diff --git a/esphome/components/esp32_ble_tracker/esp32_ble_tracker.cpp b/esphome/components/esp32_ble_tracker/esp32_ble_tracker.cpp
index cb83eb5a0d..47da2e3570 100644
--- a/esphome/components/esp32_ble_tracker/esp32_ble_tracker.cpp
+++ b/esphome/components/esp32_ble_tracker/esp32_ble_tracker.cpp
@@ -71,21 +71,24 @@ void ESP32BLETracker::setup() {
 
   global_esp32_ble_tracker = this;
 
-#ifdef USE_OTA
-  ota::get_global_ota_callback()->add_on_state_callback(
-      [this](ota::OTAState state, float progress, uint8_t error, ota::OTAComponent *comp) {
-        if (state == ota::OTA_STARTED) {
-          this->stop_scan();
-#ifdef ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT
-          for (auto *client : this->clients_) {
-            client->disconnect();
-          }
-#endif
-        }
-      });
+#ifdef USE_OTA_STATE_LISTENER
+  ota::get_global_ota_callback()->add_global_state_listener(this);
 #endif
 }
 
+#ifdef USE_OTA_STATE_LISTENER
+void ESP32BLETracker::on_ota_global_state(ota::OTAState state, float progress, uint8_t error, ota::OTAComponent *comp) {
+  if (state == ota::OTA_STARTED) {
+    this->stop_scan();
+#ifdef ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT
+    for (auto *client : this->clients_) {
+      client->disconnect();
+    }
+#endif
+  }
+}
+#endif
+
 void ESP32BLETracker::loop() {
   if (!this->parent_->is_active()) {
     this->ble_was_disabled_ = true;
diff --git a/esphome/components/esp32_ble_tracker/esp32_ble_tracker.h b/esphome/components/esp32_ble_tracker/esp32_ble_tracker.h
index 92d13a62ad..b64e36279c 100644
--- a/esphome/components/esp32_ble_tracker/esp32_ble_tracker.h
+++ b/esphome/components/esp32_ble_tracker/esp32_ble_tracker.h
@@ -22,6 +22,10 @@
 #include "esphome/components/esp32_ble/ble_uuid.h"
 #include "esphome/components/esp32_ble/ble_scan_result.h"
 
+#ifdef USE_OTA_STATE_LISTENER
+#include "esphome/components/ota/ota_backend.h"
+#endif
+
 namespace esphome::esp32_ble_tracker {
 
 using namespace esp32_ble;
@@ -241,6 +245,9 @@ class ESP32BLETracker : public Component,
                         public GAPScanEventHandler,
                         public GATTcEventHandler,
                         public BLEStatusEventHandler,
+#ifdef USE_OTA_STATE_LISTENER
+                        public ota::OTAGlobalStateListener,
+#endif
                         public Parented<ESP32BLE> {
  public:
   void set_scan_duration(uint32_t scan_duration) { scan_duration_ = scan_duration; }
@@ -274,6 +281,10 @@ class ESP32BLETracker : public Component,
   void gap_scan_event_handler(const BLEScanResult &scan_result) override;
   void ble_before_disabled_event_handler() override;
 
+#ifdef USE_OTA_STATE_LISTENER
+  void on_ota_global_state(ota::OTAState state, float progress, uint8_t error, ota::OTAComponent *comp) override;
+#endif
+
   /// Add a listener for scanner state changes
   void add_scanner_state_listener(BLEScannerStateListener *listener) {
     this->scanner_state_listeners_.push_back(listener);
diff --git a/esphome/components/esphome/ota/ota_esphome.cpp b/esphome/components/esphome/ota/ota_esphome.cpp
index 6cfd543553..b589a6119f 100644
--- a/esphome/components/esphome/ota/ota_esphome.cpp
+++ b/esphome/components/esphome/ota/ota_esphome.cpp
@@ -41,10 +41,6 @@ static constexpr size_t SHA256_HEX_SIZE = 64;  // SHA256 hash as hex string (32
 #endif  // USE_OTA_PASSWORD
 
 void ESPHomeOTAComponent::setup() {
-#ifdef USE_OTA_STATE_CALLBACK
-  ota::register_ota_platform(this);
-#endif
-
   this->server_ = socket::socket_ip_loop_monitored(SOCK_STREAM, 0);  // monitored for incoming connections
   if (this->server_ == nullptr) {
     this->log_socket_error_(LOG_STR("creation"));
@@ -297,8 +293,8 @@ void ESPHomeOTAComponent::handle_data_() {
   // accidentally trigger the update process.
   this->log_start_(LOG_STR("update"));
   this->status_set_warning();
-#ifdef USE_OTA_STATE_CALLBACK
-  this->state_callback_.call(ota::OTA_STARTED, 0.0f, 0);
+#ifdef USE_OTA_STATE_LISTENER
+  this->notify_state_(ota::OTA_STARTED, 0.0f, 0);
 #endif
 
   // This will block for a few seconds as it locks flash
@@ -357,8 +353,8 @@ void ESPHomeOTAComponent::handle_data_() {
       last_progress = now;
       float percentage = (total * 100.0f) / ota_size;
       ESP_LOGD(TAG, "Progress: %0.1f%%", percentage);
-#ifdef USE_OTA_STATE_CALLBACK
-      this->state_callback_.call(ota::OTA_IN_PROGRESS, percentage, 0);
+#ifdef USE_OTA_STATE_LISTENER
+      this->notify_state_(ota::OTA_IN_PROGRESS, percentage, 0);
 #endif
       // feed watchdog and give other tasks a chance to run
       this->yield_and_feed_watchdog_();
@@ -387,8 +383,8 @@ void ESPHomeOTAComponent::handle_data_() {
   delay(10);
   ESP_LOGI(TAG, "Update complete");
   this->status_clear_warning();
-#ifdef USE_OTA_STATE_CALLBACK
-  this->state_callback_.call(ota::OTA_COMPLETED, 100.0f, 0);
+#ifdef USE_OTA_STATE_LISTENER
+  this->notify_state_(ota::OTA_COMPLETED, 100.0f, 0);
 #endif
   delay(100);  // NOLINT
   App.safe_reboot();
@@ -402,8 +398,8 @@ error:
   }
 
   this->status_momentary_error("err", 5000);
-#ifdef USE_OTA_STATE_CALLBACK
-  this->state_callback_.call(ota::OTA_ERROR, 0.0f, static_cast<uint8_t>(error_code));
+#ifdef USE_OTA_STATE_LISTENER
+  this->notify_state_(ota::OTA_ERROR, 0.0f, static_cast<uint8_t>(error_code));
 #endif
 }
 
diff --git a/esphome/components/http_request/ota/ota_http_request.cpp b/esphome/components/http_request/ota/ota_http_request.cpp
index b257518e06..058579752e 100644
--- a/esphome/components/http_request/ota/ota_http_request.cpp
+++ b/esphome/components/http_request/ota/ota_http_request.cpp
@@ -16,12 +16,6 @@ namespace http_request {
 
 static const char *const TAG = "http_request.ota";
 
-void OtaHttpRequestComponent::setup() {
-#ifdef USE_OTA_STATE_CALLBACK
-  ota::register_ota_platform(this);
-#endif
-}
-
 void OtaHttpRequestComponent::dump_config() { ESP_LOGCONFIG(TAG, "Over-The-Air updates via HTTP request"); };
 
 void OtaHttpRequestComponent::set_md5_url(const std::string &url) {
@@ -48,24 +42,24 @@ void OtaHttpRequestComponent::flash() {
   }
 
   ESP_LOGI(TAG, "Starting update");
-#ifdef USE_OTA_STATE_CALLBACK
-  this->state_callback_.call(ota::OTA_STARTED, 0.0f, 0);
+#ifdef USE_OTA_STATE_LISTENER
+  this->notify_state_(ota::OTA_STARTED, 0.0f, 0);
 #endif
 
   auto ota_status = this->do_ota_();
 
   switch (ota_status) {
     case ota::OTA_RESPONSE_OK:
-#ifdef USE_OTA_STATE_CALLBACK
-      this->state_callback_.call(ota::OTA_COMPLETED, 100.0f, ota_status);
+#ifdef USE_OTA_STATE_LISTENER
+      this->notify_state_(ota::OTA_COMPLETED, 100.0f, ota_status);
 #endif
       delay(10);
       App.safe_reboot();
       break;
 
     default:
-#ifdef USE_OTA_STATE_CALLBACK
-      this->state_callback_.call(ota::OTA_ERROR, 0.0f, ota_status);
+#ifdef USE_OTA_STATE_LISTENER
+      this->notify_state_(ota::OTA_ERROR, 0.0f, ota_status);
 #endif
       this->md5_computed_.clear();  // will be reset at next attempt
       this->md5_expected_.clear();  // will be reset at next attempt
@@ -165,8 +159,8 @@ uint8_t OtaHttpRequestComponent::do_ota_() {
       last_progress = now;
       float percentage = container->get_bytes_read() * 100.0f / container->content_length;
       ESP_LOGD(TAG, "Progress: %0.1f%%", percentage);
-#ifdef USE_OTA_STATE_CALLBACK
-      this->state_callback_.call(ota::OTA_IN_PROGRESS, percentage, 0);
+#ifdef USE_OTA_STATE_LISTENER
+      this->notify_state_(ota::OTA_IN_PROGRESS, percentage, 0);
 #endif
     }
   }  // while
diff --git a/esphome/components/http_request/ota/ota_http_request.h b/esphome/components/http_request/ota/ota_http_request.h
index 6a86b4ab43..8735189e99 100644
--- a/esphome/components/http_request/ota/ota_http_request.h
+++ b/esphome/components/http_request/ota/ota_http_request.h
@@ -24,7 +24,6 @@ enum OtaHttpRequestError : uint8_t {
 
 class OtaHttpRequestComponent : public ota::OTAComponent, public Parented<HttpRequestComponent> {
  public:
-  void setup() override;
   void dump_config() override;
   float get_setup_priority() const override { return setup_priority::AFTER_WIFI; }
 
diff --git a/esphome/components/http_request/update/__init__.py b/esphome/components/http_request/update/__init__.py
index abb4b2a430..d84d80109a 100644
--- a/esphome/components/http_request/update/__init__.py
+++ b/esphome/components/http_request/update/__init__.py
@@ -1,5 +1,5 @@
 import esphome.codegen as cg
-from esphome.components import update
+from esphome.components import ota, update
 import esphome.config_validation as cv
 from esphome.const import CONF_SOURCE
 
@@ -38,6 +38,6 @@ async def to_code(config):
 
     cg.add(var.set_source_url(config[CONF_SOURCE]))
 
-    cg.add_define("USE_OTA_STATE_CALLBACK")
+    ota.request_ota_state_listeners()
 
     await cg.register_component(var, config)
diff --git a/esphome/components/http_request/update/http_request_update.cpp b/esphome/components/http_request/update/http_request_update.cpp
index 22cad625d1..a9392ad736 100644
--- a/esphome/components/http_request/update/http_request_update.cpp
+++ b/esphome/components/http_request/update/http_request_update.cpp
@@ -20,19 +20,19 @@ static const char *const TAG = "http_request.update";
 
 static const size_t MAX_READ_SIZE = 256;
 
-void HttpRequestUpdate::setup() {
-  this->ota_parent_->add_on_state_callback([this](ota::OTAState state, float progress, uint8_t err) {
-    if (state == ota::OTAState::OTA_IN_PROGRESS) {
-      this->state_ = update::UPDATE_STATE_INSTALLING;
-      this->update_info_.has_progress = true;
-      this->update_info_.progress = progress;
-      this->publish_state();
-    } else if (state == ota::OTAState::OTA_ABORT || state == ota::OTAState::OTA_ERROR) {
-      this->state_ = update::UPDATE_STATE_AVAILABLE;
-      this->status_set_error(LOG_STR("Failed to install firmware"));
-      this->publish_state();
-    }
-  });
+void HttpRequestUpdate::setup() { this->ota_parent_->add_state_listener(this); }
+
+void HttpRequestUpdate::on_ota_state(ota::OTAState state, float progress, uint8_t error) {
+  if (state == ota::OTAState::OTA_IN_PROGRESS) {
+    this->state_ = update::UPDATE_STATE_INSTALLING;
+    this->update_info_.has_progress = true;
+    this->update_info_.progress = progress;
+    this->publish_state();
+  } else if (state == ota::OTAState::OTA_ABORT || state == ota::OTAState::OTA_ERROR) {
+    this->state_ = update::UPDATE_STATE_AVAILABLE;
+    this->status_set_error(LOG_STR("Failed to install firmware"));
+    this->publish_state();
+  }
 }
 
 void HttpRequestUpdate::update() {
diff --git a/esphome/components/http_request/update/http_request_update.h b/esphome/components/http_request/update/http_request_update.h
index e05fdb0cc2..cf34ace18e 100644
--- a/esphome/components/http_request/update/http_request_update.h
+++ b/esphome/components/http_request/update/http_request_update.h
@@ -14,7 +14,7 @@
 namespace esphome {
 namespace http_request {
 
-class HttpRequestUpdate : public update::UpdateEntity, public PollingComponent {
+class HttpRequestUpdate final : public update::UpdateEntity, public PollingComponent, public ota::OTAStateListener {
  public:
   void setup() override;
   void update() override;
@@ -29,6 +29,8 @@ class HttpRequestUpdate : public update::UpdateEntity, public PollingComponent {
 
   float get_setup_priority() const override { return setup_priority::AFTER_WIFI; }
 
+  void on_ota_state(ota::OTAState state, float progress, uint8_t error) override;
+
  protected:
   HttpRequestComponent *request_parent_;
   OtaHttpRequestComponent *ota_parent_;
diff --git a/esphome/components/micro_wake_word/__init__.py b/esphome/components/micro_wake_word/__init__.py
index 575fb97799..0d478f749b 100644
--- a/esphome/components/micro_wake_word/__init__.py
+++ b/esphome/components/micro_wake_word/__init__.py
@@ -7,7 +7,7 @@ from urllib.parse import urljoin
 from esphome import automation, external_files, git
 from esphome.automation import register_action, register_condition
 import esphome.codegen as cg
-from esphome.components import esp32, microphone, socket
+from esphome.components import esp32, microphone, ota, socket
 import esphome.config_validation as cv
 from esphome.const import (
     CONF_FILE,
@@ -452,7 +452,7 @@ async def to_code(config):
     cg.add(var.set_microphone_source(mic_source))
 
     cg.add_define("USE_MICRO_WAKE_WORD")
-    cg.add_define("USE_OTA_STATE_CALLBACK")
+    ota.request_ota_state_listeners()
 
     esp32.add_idf_component(name="espressif/esp-tflite-micro", ref="1.3.3~1")
 
diff --git a/esphome/components/micro_wake_word/micro_wake_word.cpp b/esphome/components/micro_wake_word/micro_wake_word.cpp
index ec8fa34da4..b8377ead38 100644
--- a/esphome/components/micro_wake_word/micro_wake_word.cpp
+++ b/esphome/components/micro_wake_word/micro_wake_word.cpp
@@ -119,18 +119,21 @@ void MicroWakeWord::setup() {
     }
   });
 
-#ifdef USE_OTA
-  ota::get_global_ota_callback()->add_on_state_callback(
-      [this](ota::OTAState state, float progress, uint8_t error, ota::OTAComponent *comp) {
-        if (state == ota::OTA_STARTED) {
-          this->suspend_task_();
-        } else if (state == ota::OTA_ERROR) {
-          this->resume_task_();
-        }
-      });
+#ifdef USE_OTA_STATE_LISTENER
+  ota::get_global_ota_callback()->add_global_state_listener(this);
 #endif
 }
 
+#ifdef USE_OTA_STATE_LISTENER
+void MicroWakeWord::on_ota_global_state(ota::OTAState state, float progress, uint8_t error, ota::OTAComponent *comp) {
+  if (state == ota::OTA_STARTED) {
+    this->suspend_task_();
+  } else if (state == ota::OTA_ERROR) {
+    this->resume_task_();
+  }
+}
+#endif
+
 void MicroWakeWord::inference_task(void *params) {
   MicroWakeWord *this_mww = (MicroWakeWord *) params;
 
diff --git a/esphome/components/micro_wake_word/micro_wake_word.h b/esphome/components/micro_wake_word/micro_wake_word.h
index d46c40e48b..84261eaa5b 100644
--- a/esphome/components/micro_wake_word/micro_wake_word.h
+++ b/esphome/components/micro_wake_word/micro_wake_word.h
@@ -9,8 +9,13 @@
 
 #include "esphome/core/automation.h"
 #include "esphome/core/component.h"
+#include "esphome/core/defines.h"
 #include "esphome/core/ring_buffer.h"
 
+#ifdef USE_OTA_STATE_LISTENER
+#include "esphome/components/ota/ota_backend.h"
+#endif
+
 #include <freertos/event_groups.h>
 
 #include <frontend.h>
@@ -26,13 +31,22 @@ enum State {
   STOPPED,
 };
 
-class MicroWakeWord : public Component {
+class MicroWakeWord : public Component
+#ifdef USE_OTA_STATE_LISTENER
+    ,
+                      public ota::OTAGlobalStateListener
+#endif
+{
  public:
   void setup() override;
   void loop() override;
   float get_setup_priority() const override;
   void dump_config() override;
 
+#ifdef USE_OTA_STATE_LISTENER
+  void on_ota_global_state(ota::OTAState state, float progress, uint8_t error, ota::OTAComponent *comp) override;
+#endif
+
   void start();
   void stop();
 
diff --git a/esphome/components/ota/__init__.py b/esphome/components/ota/__init__.py
index be1b6da241..8bed9cee42 100644
--- a/esphome/components/ota/__init__.py
+++ b/esphome/components/ota/__init__.py
@@ -13,6 +13,8 @@ from esphome.const import (
 from esphome.core import CORE, coroutine_with_priority
 from esphome.coroutine import CoroPriority
 
+OTA_STATE_LISTENER_KEY = "ota_state_listener"
+
 CODEOWNERS = ["@esphome/core"]
 AUTO_LOAD = ["md5", "safe_mode"]
 
@@ -86,6 +88,7 @@ BASE_OTA_SCHEMA = cv.Schema(
 @coroutine_with_priority(CoroPriority.OTA_UPDATES)
 async def to_code(config):
     cg.add_define("USE_OTA")
+    CORE.add_job(final_step)
 
     if CORE.is_rp2040 and CORE.using_arduino:
         cg.add_library("Updater", None)
@@ -119,7 +122,24 @@ async def ota_to_code(var, config):
         await automation.build_automation(trigger, [(cg.uint8, "x")], conf)
         use_state_callback = True
     if use_state_callback:
-        cg.add_define("USE_OTA_STATE_CALLBACK")
+        request_ota_state_listeners()
+
+
+def request_ota_state_listeners() -> None:
+    """Request that OTA state listeners be compiled in.
+
+    Components that need to be notified about OTA state changes (start, progress,
+    complete, error) should call this function during their code generation.
+    This enables the add_state_listener() API on OTAComponent.
+    """
+    CORE.data[OTA_STATE_LISTENER_KEY] = True
+
+
+@coroutine_with_priority(CoroPriority.FINAL)
+async def final_step():
+    """Final code generation step to configure optional OTA features."""
+    if CORE.data.get(OTA_STATE_LISTENER_KEY, False):
+        cg.add_define("USE_OTA_STATE_LISTENER")
 
 
 FILTER_SOURCE_FILES = filter_source_files_from_platform(
diff --git a/esphome/components/ota/automation.h b/esphome/components/ota/automation.h
index 7e1a60f3ce..92c0050ba0 100644
--- a/esphome/components/ota/automation.h
+++ b/esphome/components/ota/automation.h
@@ -1,5 +1,5 @@
 #pragma once
-#ifdef USE_OTA_STATE_CALLBACK
+#ifdef USE_OTA_STATE_LISTENER
 #include "ota_backend.h"
 
 #include "esphome/core/automation.h"
@@ -7,70 +7,64 @@
 namespace esphome {
 namespace ota {
 
-class OTAStateChangeTrigger : public Trigger<OTAState> {
+class OTAStateChangeTrigger final : public Trigger<OTAState>, public OTAStateListener {
  public:
-  explicit OTAStateChangeTrigger(OTAComponent *parent) {
-    parent->add_on_state_callback([this, parent](OTAState state, float progress, uint8_t error) {
-      if (!parent->is_failed()) {
-        trigger(state);
-      }
-    });
+  explicit OTAStateChangeTrigger(OTAComponent *parent) : parent_(parent) { parent->add_state_listener(this); }
+
+  void on_ota_state(OTAState state, float progress, uint8_t error) override {
+    if (!this->parent_->is_failed()) {
+      this->trigger(state);
+    }
   }
+
+ protected:
+  OTAComponent *parent_;
 };
 
-class OTAStartTrigger : public Trigger<> {
+template<OTAState State> class OTAStateTrigger final : public Trigger<>, public OTAStateListener {
  public:
-  explicit OTAStartTrigger(OTAComponent *parent) {
-    parent->add_on_state_callback([this, parent](OTAState state, float progress, uint8_t error) {
-      if (state == OTA_STARTED && !parent->is_failed()) {
-        trigger();
-      }
-    });
+  explicit OTAStateTrigger(OTAComponent *parent) : parent_(parent) { parent->add_state_listener(this); }
+
+  void on_ota_state(OTAState state, float progress, uint8_t error) override {
+    if (state == State && !this->parent_->is_failed()) {
+      this->trigger();
+    }
   }
+
+ protected:
+  OTAComponent *parent_;
 };
 
-class OTAProgressTrigger : public Trigger<float> {
+using OTAStartTrigger = OTAStateTrigger<OTA_STARTED>;
+using OTAEndTrigger = OTAStateTrigger<OTA_COMPLETED>;
+using OTAAbortTrigger = OTAStateTrigger<OTA_ABORT>;
+
+class OTAProgressTrigger final : public Trigger<float>, public OTAStateListener {
  public:
-  explicit OTAProgressTrigger(OTAComponent *parent) {
-    parent->add_on_state_callback([this, parent](OTAState state, float progress, uint8_t error) {
-      if (state == OTA_IN_PROGRESS && !parent->is_failed()) {
-        trigger(progress);
-      }
-    });
+  explicit OTAProgressTrigger(OTAComponent *parent) : parent_(parent) { parent->add_state_listener(this); }
+
+  void on_ota_state(OTAState state, float progress, uint8_t error) override {
+    if (state == OTA_IN_PROGRESS && !this->parent_->is_failed()) {
+      this->trigger(progress);
+    }
   }
+
+ protected:
+  OTAComponent *parent_;
 };
 
-class OTAEndTrigger : public Trigger<> {
+class OTAErrorTrigger final : public Trigger<uint8_t>, public OTAStateListener {
  public:
-  explicit OTAEndTrigger(OTAComponent *parent) {
-    parent->add_on_state_callback([this, parent](OTAState state, float progress, uint8_t error) {
-      if (state == OTA_COMPLETED && !parent->is_failed()) {
-        trigger();
-      }
-    });
-  }
-};
+  explicit OTAErrorTrigger(OTAComponent *parent) : parent_(parent) { parent->add_state_listener(this); }
 
-class OTAAbortTrigger : public Trigger<> {
- public:
-  explicit OTAAbortTrigger(OTAComponent *parent) {
-    parent->add_on_state_callback([this, parent](OTAState state, float progress, uint8_t error) {
-      if (state == OTA_ABORT && !parent->is_failed()) {
-        trigger();
-      }
-    });
+  void on_ota_state(OTAState state, float progress, uint8_t error) override {
+    if (state == OTA_ERROR && !this->parent_->is_failed()) {
+      this->trigger(error);
+    }
   }
-};
 
-class OTAErrorTrigger : public Trigger<uint8_t> {
- public:
-  explicit OTAErrorTrigger(OTAComponent *parent) {
-    parent->add_on_state_callback([this, parent](OTAState state, float progress, uint8_t error) {
-      if (state == OTA_ERROR && !parent->is_failed()) {
-        trigger(error);
-      }
-    });
-  }
+ protected:
+  OTAComponent *parent_;
 };
 
 }  // namespace ota
diff --git a/esphome/components/ota/ota_backend.cpp b/esphome/components/ota/ota_backend.cpp
index 30de4ec4b3..8fb9f67214 100644
--- a/esphome/components/ota/ota_backend.cpp
+++ b/esphome/components/ota/ota_backend.cpp
@@ -3,7 +3,7 @@
 namespace esphome {
 namespace ota {
 
-#ifdef USE_OTA_STATE_CALLBACK
+#ifdef USE_OTA_STATE_LISTENER
 OTAGlobalCallback *global_ota_callback{nullptr};  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
 
 OTAGlobalCallback *get_global_ota_callback() {
@@ -13,7 +13,12 @@ OTAGlobalCallback *get_global_ota_callback() {
   return global_ota_callback;
 }
 
-void register_ota_platform(OTAComponent *ota_caller) { get_global_ota_callback()->register_ota(ota_caller); }
+void OTAComponent::notify_state_(OTAState state, float progress, uint8_t error) {
+  for (auto *listener : this->state_listeners_) {
+    listener->on_ota_state(state, progress, error);
+  }
+  get_global_ota_callback()->notify_ota_state(state, progress, error, this);
+}
 #endif
 
 }  // namespace ota
diff --git a/esphome/components/ota/ota_backend.h b/esphome/components/ota/ota_backend.h
index 64ee0b9f7c..e03afd4fc6 100644
--- a/esphome/components/ota/ota_backend.h
+++ b/esphome/components/ota/ota_backend.h
@@ -4,8 +4,8 @@
 #include "esphome/core/defines.h"
 #include "esphome/core/helpers.h"
 
-#ifdef USE_OTA_STATE_CALLBACK
-#include "esphome/core/automation.h"
+#ifdef USE_OTA_STATE_LISTENER
+#include <vector>
 #endif
 
 namespace esphome {
@@ -60,62 +60,75 @@ class OTABackend {
   virtual bool supports_compression() = 0;
 };
 
-class OTAComponent : public Component {
-#ifdef USE_OTA_STATE_CALLBACK
+/** Listener interface for OTA state changes.
+ *
+ * Components can implement this interface to receive OTA state updates
+ * without the overhead of std::function callbacks.
+ */
+class OTAStateListener {
  public:
-  void add_on_state_callback(std::function<void(ota::OTAState, float, uint8_t)> &&callback) {
-    this->state_callback_.add(std::move(callback));
-  }
+  virtual ~OTAStateListener() = default;
+  virtual void on_ota_state(OTAState state, float progress, uint8_t error) = 0;
+};
+
+class OTAComponent : public Component {
+#ifdef USE_OTA_STATE_LISTENER
+ public:
+  void add_state_listener(OTAStateListener *listener) { this->state_listeners_.push_back(listener); }
 
  protected:
-  /** Extended callback manager with deferred call support.
+  void notify_state_(OTAState state, float progress, uint8_t error);
+
+  /** Notify state with deferral to main loop (for thread safety).
    *
-   * This adds a call_deferred() method for thread-safe execution from other tasks.
+   * This should be used by OTA implementations that run in separate tasks
+   * (like web_server OTA) to ensure listeners execute in the main loop.
    */
-  class StateCallbackManager : public CallbackManager<void(OTAState, float, uint8_t)> {
-   public:
-    StateCallbackManager(OTAComponent *component) : component_(component) {}
+  void notify_state_deferred_(OTAState state, float progress, uint8_t error) {
+    this->defer([this, state, progress, error]() { this->notify_state_(state, progress, error); });
+  }
 
-    /** Call callbacks with deferral to main loop (for thread safety).
-     *
-     * This should be used by OTA implementations that run in separate tasks
-     * (like web_server OTA) to ensure callbacks execute in the main loop.
-     */
-    void call_deferred(ota::OTAState state, float progress, uint8_t error) {
-      component_->defer([this, state, progress, error]() { this->call(state, progress, error); });
-    }
-
-   private:
-    OTAComponent *component_;
-  };
-
-  StateCallbackManager state_callback_{this};
+  std::vector<OTAStateListener *> state_listeners_;
 #endif
 };
 
-#ifdef USE_OTA_STATE_CALLBACK
+#ifdef USE_OTA_STATE_LISTENER
+
+/** Listener interface for global OTA state changes (includes OTA component pointer).
+ *
+ * Used by OTAGlobalCallback to aggregate state from multiple OTA components.
+ */
+class OTAGlobalStateListener {
+ public:
+  virtual ~OTAGlobalStateListener() = default;
+  virtual void on_ota_global_state(OTAState state, float progress, uint8_t error, OTAComponent *component) = 0;
+};
+
+/** Global callback that aggregates OTA state from all OTA components.
+ *
+ * OTA components call notify_ota_state() directly with their pointer,
+ * which forwards the event to all registered global listeners.
+ */
 class OTAGlobalCallback {
  public:
-  void register_ota(OTAComponent *ota_caller) {
-    ota_caller->add_on_state_callback([this, ota_caller](OTAState state, float progress, uint8_t error) {
-      this->state_callback_.call(state, progress, error, ota_caller);
-    });
-  }
-  void add_on_state_callback(std::function<void(OTAState, float, uint8_t, OTAComponent *)> &&callback) {
-    this->state_callback_.add(std::move(callback));
+  void add_global_state_listener(OTAGlobalStateListener *listener) { this->global_listeners_.push_back(listener); }
+
+  void notify_ota_state(OTAState state, float progress, uint8_t error, OTAComponent *component) {
+    for (auto *listener : this->global_listeners_) {
+      listener->on_ota_global_state(state, progress, error, component);
+    }
   }
 
  protected:
-  CallbackManager<void(OTAState, float, uint8_t, OTAComponent *)> state_callback_{};
+  std::vector<OTAGlobalStateListener *> global_listeners_;
 };
 
 OTAGlobalCallback *get_global_ota_callback();
-void register_ota_platform(OTAComponent *ota_caller);
 
 // OTA implementations should use:
-// - state_callback_.call() when already in main loop (e.g., esphome OTA)
-// - state_callback_.call_deferred() when in separate task (e.g., web_server OTA)
-// This ensures proper callback execution in all contexts.
+// - notify_state_() when already in main loop (e.g., esphome OTA)
+// - notify_state_deferred_() when in separate task (e.g., web_server OTA)
+// This ensures proper listener execution in all contexts.
 #endif
 std::unique_ptr<ota::OTABackend> make_ota_backend();
 
diff --git a/esphome/components/speaker/media_player/__init__.py b/esphome/components/speaker/media_player/__init__.py
index 062bff92f8..4ca57f2c4a 100644
--- a/esphome/components/speaker/media_player/__init__.py
+++ b/esphome/components/speaker/media_player/__init__.py
@@ -6,7 +6,7 @@ from pathlib import Path
 
 from esphome import automation, external_files
 import esphome.codegen as cg
-from esphome.components import audio, esp32, media_player, network, psram, speaker
+from esphome.components import audio, esp32, media_player, network, ota, psram, speaker
 import esphome.config_validation as cv
 from esphome.const import (
     CONF_BUFFER_SIZE,
@@ -342,7 +342,7 @@ async def to_code(config):
     var = await media_player.new_media_player(config)
     await cg.register_component(var, config)
 
-    cg.add_define("USE_OTA_STATE_CALLBACK")
+    ota.request_ota_state_listeners()
 
     cg.add(var.set_buffer_size(config[CONF_BUFFER_SIZE]))
 
diff --git a/esphome/components/speaker/media_player/speaker_media_player.cpp b/esphome/components/speaker/media_player/speaker_media_player.cpp
index b45a78010a..5722aab195 100644
--- a/esphome/components/speaker/media_player/speaker_media_player.cpp
+++ b/esphome/components/speaker/media_player/speaker_media_player.cpp
@@ -66,25 +66,8 @@ void SpeakerMediaPlayer::setup() {
     this->set_mute_state_(false);
   }
 
-#ifdef USE_OTA
-  ota::get_global_ota_callback()->add_on_state_callback(
-      [this](ota::OTAState state, float progress, uint8_t error, ota::OTAComponent *comp) {
-        if (state == ota::OTA_STARTED) {
-          if (this->media_pipeline_ != nullptr) {
-            this->media_pipeline_->suspend_tasks();
-          }
-          if (this->announcement_pipeline_ != nullptr) {
-            this->announcement_pipeline_->suspend_tasks();
-          }
-        } else if (state == ota::OTA_ERROR) {
-          if (this->media_pipeline_ != nullptr) {
-            this->media_pipeline_->resume_tasks();
-          }
-          if (this->announcement_pipeline_ != nullptr) {
-            this->announcement_pipeline_->resume_tasks();
-          }
-        }
-      });
+#ifdef USE_OTA_STATE_LISTENER
+  ota::get_global_ota_callback()->add_global_state_listener(this);
 #endif
 
   this->announcement_pipeline_ =
@@ -300,6 +283,27 @@ void SpeakerMediaPlayer::watch_media_commands_() {
   }
 }
 
+#ifdef USE_OTA_STATE_LISTENER
+void SpeakerMediaPlayer::on_ota_global_state(ota::OTAState state, float progress, uint8_t error,
+                                             ota::OTAComponent *comp) {
+  if (state == ota::OTA_STARTED) {
+    if (this->media_pipeline_ != nullptr) {
+      this->media_pipeline_->suspend_tasks();
+    }
+    if (this->announcement_pipeline_ != nullptr) {
+      this->announcement_pipeline_->suspend_tasks();
+    }
+  } else if (state == ota::OTA_ERROR) {
+    if (this->media_pipeline_ != nullptr) {
+      this->media_pipeline_->resume_tasks();
+    }
+    if (this->announcement_pipeline_ != nullptr) {
+      this->announcement_pipeline_->resume_tasks();
+    }
+  }
+}
+#endif
+
 void SpeakerMediaPlayer::loop() {
   this->watch_media_commands_();
 
diff --git a/esphome/components/speaker/media_player/speaker_media_player.h b/esphome/components/speaker/media_player/speaker_media_player.h
index 967772d1a5..f1c564b63d 100644
--- a/esphome/components/speaker/media_player/speaker_media_player.h
+++ b/esphome/components/speaker/media_player/speaker_media_player.h
@@ -5,14 +5,18 @@
 #include "audio_pipeline.h"
 
 #include "esphome/components/audio/audio.h"
-
 #include "esphome/components/media_player/media_player.h"
 #include "esphome/components/speaker/speaker.h"
 
 #include "esphome/core/automation.h"
 #include "esphome/core/component.h"
+#include "esphome/core/defines.h"
 #include "esphome/core/preferences.h"
 
+#ifdef USE_OTA_STATE_LISTENER
+#include "esphome/components/ota/ota_backend.h"
+#endif
+
 #include <deque>
 #include <freertos/FreeRTOS.h>
 #include <freertos/queue.h>
@@ -39,12 +43,22 @@ struct VolumeRestoreState {
   bool is_muted;
 };
 
-class SpeakerMediaPlayer : public Component, public media_player::MediaPlayer {
+class SpeakerMediaPlayer : public Component,
+                           public media_player::MediaPlayer
+#ifdef USE_OTA_STATE_LISTENER
+    ,
+                           public ota::OTAGlobalStateListener
+#endif
+{
  public:
   float get_setup_priority() const override { return esphome::setup_priority::PROCESSOR; }
   void setup() override;
   void loop() override;
 
+#ifdef USE_OTA_STATE_LISTENER
+  void on_ota_global_state(ota::OTAState state, float progress, uint8_t error, ota::OTAComponent *comp) override;
+#endif
+
   // MediaPlayer implementations
   media_player::MediaPlayerTraits get_traits() override;
   bool is_muted() const override { return this->is_muted_; }
diff --git a/esphome/components/web_server/ota/ota_web_server.cpp b/esphome/components/web_server/ota/ota_web_server.cpp
index 7929f3647f..f612aa056c 100644
--- a/esphome/components/web_server/ota/ota_web_server.cpp
+++ b/esphome/components/web_server/ota/ota_web_server.cpp
@@ -84,9 +84,9 @@ void OTARequestHandler::report_ota_progress_(AsyncWebServerRequest *request) {
     } else {
       ESP_LOGD(TAG, "OTA in progress: %" PRIu32 " bytes read", this->ota_read_length_);
     }
-#ifdef USE_OTA_STATE_CALLBACK
-    // Report progress - use call_deferred since we're in web server task
-    this->parent_->state_callback_.call_deferred(ota::OTA_IN_PROGRESS, percentage, 0);
+#ifdef USE_OTA_STATE_LISTENER
+    // Report progress - use notify_state_deferred_ since we're in web server task
+    this->parent_->notify_state_deferred_(ota::OTA_IN_PROGRESS, percentage, 0);
 #endif
     this->last_ota_progress_ = now;
   }
@@ -114,9 +114,9 @@ void OTARequestHandler::handleUpload(AsyncWebServerRequest *request, const Platf
     // Initialize OTA on first call
     this->ota_init_(filename.c_str());
 
-#ifdef USE_OTA_STATE_CALLBACK
-    // Notify OTA started - use call_deferred since we're in web server task
-    this->parent_->state_callback_.call_deferred(ota::OTA_STARTED, 0.0f, 0);
+#ifdef USE_OTA_STATE_LISTENER
+    // Notify OTA started - use notify_state_deferred_ since we're in web server task
+    this->parent_->notify_state_deferred_(ota::OTA_STARTED, 0.0f, 0);
 #endif
 
     // Platform-specific pre-initialization
@@ -134,9 +134,9 @@ void OTARequestHandler::handleUpload(AsyncWebServerRequest *request, const Platf
     this->ota_backend_ = ota::make_ota_backend();
     if (!this->ota_backend_) {
       ESP_LOGE(TAG, "Failed to create OTA backend");
-#ifdef USE_OTA_STATE_CALLBACK
-      this->parent_->state_callback_.call_deferred(ota::OTA_ERROR, 0.0f,
-                                                   static_cast<uint8_t>(ota::OTA_RESPONSE_ERROR_UNKNOWN));
+#ifdef USE_OTA_STATE_LISTENER
+      this->parent_->notify_state_deferred_(ota::OTA_ERROR, 0.0f,
+                                            static_cast<uint8_t>(ota::OTA_RESPONSE_ERROR_UNKNOWN));
 #endif
       return;
     }
@@ -148,8 +148,8 @@ void OTARequestHandler::handleUpload(AsyncWebServerRequest *request, const Platf
     if (error_code != ota::OTA_RESPONSE_OK) {
       ESP_LOGE(TAG, "OTA begin failed: %d", error_code);
       this->ota_backend_.reset();
-#ifdef USE_OTA_STATE_CALLBACK
-      this->parent_->state_callback_.call_deferred(ota::OTA_ERROR, 0.0f, static_cast<uint8_t>(error_code));
+#ifdef USE_OTA_STATE_LISTENER
+      this->parent_->notify_state_deferred_(ota::OTA_ERROR, 0.0f, static_cast<uint8_t>(error_code));
 #endif
       return;
     }
@@ -166,8 +166,8 @@ void OTARequestHandler::handleUpload(AsyncWebServerRequest *request, const Platf
       ESP_LOGE(TAG, "OTA write failed: %d", error_code);
       this->ota_backend_->abort();
       this->ota_backend_.reset();
-#ifdef USE_OTA_STATE_CALLBACK
-      this->parent_->state_callback_.call_deferred(ota::OTA_ERROR, 0.0f, static_cast<uint8_t>(error_code));
+#ifdef USE_OTA_STATE_LISTENER
+      this->parent_->notify_state_deferred_(ota::OTA_ERROR, 0.0f, static_cast<uint8_t>(error_code));
 #endif
       return;
     }
@@ -186,15 +186,15 @@ void OTARequestHandler::handleUpload(AsyncWebServerRequest *request, const Platf
     error_code = this->ota_backend_->end();
     if (error_code == ota::OTA_RESPONSE_OK) {
       this->ota_success_ = true;
-#ifdef USE_OTA_STATE_CALLBACK
-      // Report completion before reboot - use call_deferred since we're in web server task
-      this->parent_->state_callback_.call_deferred(ota::OTA_COMPLETED, 100.0f, 0);
+#ifdef USE_OTA_STATE_LISTENER
+      // Report completion before reboot - use notify_state_deferred_ since we're in web server task
+      this->parent_->notify_state_deferred_(ota::OTA_COMPLETED, 100.0f, 0);
 #endif
       this->schedule_ota_reboot_();
     } else {
       ESP_LOGE(TAG, "OTA end failed: %d", error_code);
-#ifdef USE_OTA_STATE_CALLBACK
-      this->parent_->state_callback_.call_deferred(ota::OTA_ERROR, 0.0f, static_cast<uint8_t>(error_code));
+#ifdef USE_OTA_STATE_LISTENER
+      this->parent_->notify_state_deferred_(ota::OTA_ERROR, 0.0f, static_cast<uint8_t>(error_code));
 #endif
     }
     this->ota_backend_.reset();
@@ -232,10 +232,6 @@ void WebServerOTAComponent::setup() {
 
   // AsyncWebServer takes ownership of the handler and will delete it when the server is destroyed
   base->add_handler(new OTARequestHandler(this));  // NOLINT
-#ifdef USE_OTA_STATE_CALLBACK
-  // Register with global OTA callback system
-  ota::register_ota_platform(this);
-#endif
 }
 
 void WebServerOTAComponent::dump_config() { ESP_LOGCONFIG(TAG, "Web Server OTA"); }
diff --git a/esphome/core/defines.h b/esphome/core/defines.h
index 4cbe683723..0c12b29eb7 100644
--- a/esphome/core/defines.h
+++ b/esphome/core/defines.h
@@ -146,7 +146,7 @@
 #define USE_OTA_PASSWORD
 #define USE_OTA_SHA256
 #define ALLOW_OTA_DOWNGRADE_MD5
-#define USE_OTA_STATE_CALLBACK
+#define USE_OTA_STATE_LISTENER
 #define USE_OTA_VERSION 2
 #define USE_TIME_TIMEZONE
 #define USE_WIFI

From ada6c42f3f021ec57f7864185c635feee28d7dd4 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Fri, 19 Dec 2025 11:48:14 -1000
Subject: [PATCH 6/7] [alarm_control_panel] Remove redundant per-state
 callbacks (#12171)

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
---
 .../alarm_control_panel.cpp                   |  46 +--
 .../alarm_control_panel/alarm_control_panel.h |  63 +---
 .../alarm_control_panel/automation.h          |  66 ++--
 ...alarm_control_panel_state_transitions.yaml | 106 ++++++
 ...t_alarm_control_panel_state_transitions.py | 319 ++++++++++++++++++
 5 files changed, 453 insertions(+), 147 deletions(-)
 create mode 100644 tests/integration/fixtures/alarm_control_panel_state_transitions.yaml
 create mode 100644 tests/integration/test_alarm_control_panel_state_transitions.py

diff --git a/esphome/components/alarm_control_panel/alarm_control_panel.cpp b/esphome/components/alarm_control_panel/alarm_control_panel.cpp
index c29e02c8ef..f938155dd3 100644
--- a/esphome/components/alarm_control_panel/alarm_control_panel.cpp
+++ b/esphome/components/alarm_control_panel/alarm_control_panel.cpp
@@ -35,26 +35,12 @@ void AlarmControlPanel::publish_state(AlarmControlPanelState state) {
     ESP_LOGD(TAG, "Set state to: %s, previous: %s", LOG_STR_ARG(alarm_control_panel_state_to_string(state)),
              LOG_STR_ARG(alarm_control_panel_state_to_string(prev_state)));
     this->current_state_ = state;
+    // Single state callback - triggers check get_state() for specific states
     this->state_callback_.call();
 #if defined(USE_ALARM_CONTROL_PANEL) && defined(USE_CONTROLLER_REGISTRY)
     ControllerRegistry::notify_alarm_control_panel_update(this);
 #endif
-    if (state == ACP_STATE_TRIGGERED) {
-      this->triggered_callback_.call();
-    } else if (state == ACP_STATE_ARMING) {
-      this->arming_callback_.call();
-    } else if (state == ACP_STATE_PENDING) {
-      this->pending_callback_.call();
-    } else if (state == ACP_STATE_ARMED_HOME) {
-      this->armed_home_callback_.call();
-    } else if (state == ACP_STATE_ARMED_NIGHT) {
-      this->armed_night_callback_.call();
-    } else if (state == ACP_STATE_ARMED_AWAY) {
-      this->armed_away_callback_.call();
-    } else if (state == ACP_STATE_DISARMED) {
-      this->disarmed_callback_.call();
-    }
-
+    // Cleared fires when leaving TRIGGERED state
     if (prev_state == ACP_STATE_TRIGGERED) {
       this->cleared_callback_.call();
     }
@@ -69,34 +55,6 @@ void AlarmControlPanel::add_on_state_callback(std::function<void()> &&callback)
   this->state_callback_.add(std::move(callback));
 }
 
-void AlarmControlPanel::add_on_triggered_callback(std::function<void()> &&callback) {
-  this->triggered_callback_.add(std::move(callback));
-}
-
-void AlarmControlPanel::add_on_arming_callback(std::function<void()> &&callback) {
-  this->arming_callback_.add(std::move(callback));
-}
-
-void AlarmControlPanel::add_on_armed_home_callback(std::function<void()> &&callback) {
-  this->armed_home_callback_.add(std::move(callback));
-}
-
-void AlarmControlPanel::add_on_armed_night_callback(std::function<void()> &&callback) {
-  this->armed_night_callback_.add(std::move(callback));
-}
-
-void AlarmControlPanel::add_on_armed_away_callback(std::function<void()> &&callback) {
-  this->armed_away_callback_.add(std::move(callback));
-}
-
-void AlarmControlPanel::add_on_pending_callback(std::function<void()> &&callback) {
-  this->pending_callback_.add(std::move(callback));
-}
-
-void AlarmControlPanel::add_on_disarmed_callback(std::function<void()> &&callback) {
-  this->disarmed_callback_.add(std::move(callback));
-}
-
 void AlarmControlPanel::add_on_cleared_callback(std::function<void()> &&callback) {
   this->cleared_callback_.add(std::move(callback));
 }
diff --git a/esphome/components/alarm_control_panel/alarm_control_panel.h b/esphome/components/alarm_control_panel/alarm_control_panel.h
index 85c2b2148e..c46edc11c2 100644
--- a/esphome/components/alarm_control_panel/alarm_control_panel.h
+++ b/esphome/components/alarm_control_panel/alarm_control_panel.h
@@ -35,54 +35,13 @@ class AlarmControlPanel : public EntityBase {
    */
   void publish_state(AlarmControlPanelState state);
 
-  /** Add a callback for when the state of the alarm_control_panel changes
+  /** Add a callback for when the state of the alarm_control_panel changes.
+   * Triggers can check get_state() to determine the new state.
    *
    * @param callback The callback function
    */
   void add_on_state_callback(std::function<void()> &&callback);
 
-  /** Add a callback for when the state of the alarm_control_panel chanes to triggered
-   *
-   * @param callback The callback function
-   */
-  void add_on_triggered_callback(std::function<void()> &&callback);
-
-  /** Add a callback for when the state of the alarm_control_panel chanes to arming
-   *
-   * @param callback The callback function
-   */
-  void add_on_arming_callback(std::function<void()> &&callback);
-
-  /** Add a callback for when the state of the alarm_control_panel changes to pending
-   *
-   * @param callback The callback function
-   */
-  void add_on_pending_callback(std::function<void()> &&callback);
-
-  /** Add a callback for when the state of the alarm_control_panel changes to armed_home
-   *
-   * @param callback The callback function
-   */
-  void add_on_armed_home_callback(std::function<void()> &&callback);
-
-  /** Add a callback for when the state of the alarm_control_panel changes to armed_night
-   *
-   * @param callback The callback function
-   */
-  void add_on_armed_night_callback(std::function<void()> &&callback);
-
-  /** Add a callback for when the state of the alarm_control_panel changes to armed_away
-   *
-   * @param callback The callback function
-   */
-  void add_on_armed_away_callback(std::function<void()> &&callback);
-
-  /** Add a callback for when the state of the alarm_control_panel changes to disarmed
-   *
-   * @param callback The callback function
-   */
-  void add_on_disarmed_callback(std::function<void()> &&callback);
-
   /** Add a callback for when the state of the alarm_control_panel clears from triggered
    *
    * @param callback The callback function
@@ -172,23 +131,9 @@ class AlarmControlPanel : public EntityBase {
   uint32_t last_update_;
   // the call control function
   virtual void control(const AlarmControlPanelCall &call) = 0;
-  // state callback
+  // state callback - triggers check get_state() for specific state
   CallbackManager<void()> state_callback_{};
-  // trigger callback
-  CallbackManager<void()> triggered_callback_{};
-  // arming callback
-  CallbackManager<void()> arming_callback_{};
-  // pending callback
-  CallbackManager<void()> pending_callback_{};
-  // armed_home callback
-  CallbackManager<void()> armed_home_callback_{};
-  // armed_night callback
-  CallbackManager<void()> armed_night_callback_{};
-  // armed_away callback
-  CallbackManager<void()> armed_away_callback_{};
-  // disarmed callback
-  CallbackManager<void()> disarmed_callback_{};
-  // clear callback
+  // clear callback - fires when leaving TRIGGERED state
   CallbackManager<void()> cleared_callback_{};
   // chime callback
   CallbackManager<void()> chime_callback_{};
diff --git a/esphome/components/alarm_control_panel/automation.h b/esphome/components/alarm_control_panel/automation.h
index db2ef78158..af4a14e27a 100644
--- a/esphome/components/alarm_control_panel/automation.h
+++ b/esphome/components/alarm_control_panel/automation.h
@@ -6,6 +6,7 @@
 namespace esphome {
 namespace alarm_control_panel {
 
+/// Trigger on any state change
 class StateTrigger : public Trigger<> {
  public:
   explicit StateTrigger(AlarmControlPanel *alarm_control_panel) {
@@ -13,55 +14,30 @@ class StateTrigger : public Trigger<> {
   }
 };
 
-class TriggeredTrigger : public Trigger<> {
+/// Template trigger that fires when entering a specific state
+template<AlarmControlPanelState State> class StateEnterTrigger : public Trigger<> {
  public:
-  explicit TriggeredTrigger(AlarmControlPanel *alarm_control_panel) {
-    alarm_control_panel->add_on_triggered_callback([this]() { this->trigger(); });
+  explicit StateEnterTrigger(AlarmControlPanel *alarm_control_panel) : alarm_control_panel_(alarm_control_panel) {
+    alarm_control_panel->add_on_state_callback([this]() {
+      if (this->alarm_control_panel_->get_state() == State)
+        this->trigger();
+    });
   }
+
+ protected:
+  AlarmControlPanel *alarm_control_panel_;
 };
 
-class ArmingTrigger : public Trigger<> {
- public:
-  explicit ArmingTrigger(AlarmControlPanel *alarm_control_panel) {
-    alarm_control_panel->add_on_arming_callback([this]() { this->trigger(); });
-  }
-};
-
-class PendingTrigger : public Trigger<> {
- public:
-  explicit PendingTrigger(AlarmControlPanel *alarm_control_panel) {
-    alarm_control_panel->add_on_pending_callback([this]() { this->trigger(); });
-  }
-};
-
-class ArmedHomeTrigger : public Trigger<> {
- public:
-  explicit ArmedHomeTrigger(AlarmControlPanel *alarm_control_panel) {
-    alarm_control_panel->add_on_armed_home_callback([this]() { this->trigger(); });
-  }
-};
-
-class ArmedNightTrigger : public Trigger<> {
- public:
-  explicit ArmedNightTrigger(AlarmControlPanel *alarm_control_panel) {
-    alarm_control_panel->add_on_armed_night_callback([this]() { this->trigger(); });
-  }
-};
-
-class ArmedAwayTrigger : public Trigger<> {
- public:
-  explicit ArmedAwayTrigger(AlarmControlPanel *alarm_control_panel) {
-    alarm_control_panel->add_on_armed_away_callback([this]() { this->trigger(); });
-  }
-};
-
-class DisarmedTrigger : public Trigger<> {
- public:
-  explicit DisarmedTrigger(AlarmControlPanel *alarm_control_panel) {
-    alarm_control_panel->add_on_disarmed_callback([this]() { this->trigger(); });
-  }
-};
+// Type aliases for state-specific triggers
+using TriggeredTrigger = StateEnterTrigger<ACP_STATE_TRIGGERED>;
+using ArmingTrigger = StateEnterTrigger<ACP_STATE_ARMING>;
+using PendingTrigger = StateEnterTrigger<ACP_STATE_PENDING>;
+using ArmedHomeTrigger = StateEnterTrigger<ACP_STATE_ARMED_HOME>;
+using ArmedNightTrigger = StateEnterTrigger<ACP_STATE_ARMED_NIGHT>;
+using ArmedAwayTrigger = StateEnterTrigger<ACP_STATE_ARMED_AWAY>;
+using DisarmedTrigger = StateEnterTrigger<ACP_STATE_DISARMED>;
 
+/// Trigger when leaving TRIGGERED state (alarm cleared)
 class ClearedTrigger : public Trigger<> {
  public:
   explicit ClearedTrigger(AlarmControlPanel *alarm_control_panel) {
@@ -69,6 +45,7 @@ class ClearedTrigger : public Trigger<> {
   }
 };
 
+/// Trigger on chime event (zone opened while disarmed)
 class ChimeTrigger : public Trigger<> {
  public:
   explicit ChimeTrigger(AlarmControlPanel *alarm_control_panel) {
@@ -76,6 +53,7 @@ class ChimeTrigger : public Trigger<> {
   }
 };
 
+/// Trigger on ready state change
 class ReadyTrigger : public Trigger<> {
  public:
   explicit ReadyTrigger(AlarmControlPanel *alarm_control_panel) {
diff --git a/tests/integration/fixtures/alarm_control_panel_state_transitions.yaml b/tests/integration/fixtures/alarm_control_panel_state_transitions.yaml
new file mode 100644
index 0000000000..1edb401a0d
--- /dev/null
+++ b/tests/integration/fixtures/alarm_control_panel_state_transitions.yaml
@@ -0,0 +1,106 @@
+esphome:
+  name: alarm-state-transitions
+  friendly_name: "Alarm Control Panel State Transitions Test"
+
+logger:
+
+host:
+
+globals:
+  - id: door_sensor_state
+    type: bool
+    initial_value: "false"
+  - id: chime_sensor_state
+    type: bool
+    initial_value: "false"
+
+switch:
+  # Switch to control the door sensor state
+  - platform: template
+    id: door_sensor_switch
+    name: "Door Sensor Switch"
+    optimistic: true
+    turn_on_action:
+      - globals.set:
+          id: door_sensor_state
+          value: "true"
+    turn_off_action:
+      - globals.set:
+          id: door_sensor_state
+          value: "false"
+  # Switch to control the chime sensor state
+  - platform: template
+    id: chime_sensor_switch
+    name: "Chime Sensor Switch"
+    optimistic: true
+    turn_on_action:
+      - globals.set:
+          id: chime_sensor_state
+          value: "true"
+    turn_off_action:
+      - globals.set:
+          id: chime_sensor_state
+          value: "false"
+
+binary_sensor:
+  - platform: template
+    id: door_sensor
+    name: "Door Sensor"
+    lambda: |-
+      return id(door_sensor_state);
+  - platform: template
+    id: chime_sensor
+    name: "Chime Sensor"
+    lambda: |-
+      return id(chime_sensor_state);
+
+alarm_control_panel:
+  - platform: template
+    id: test_alarm
+    name: "Test Alarm"
+    codes:
+      - "1234"
+    requires_code_to_arm: true
+    # Short timeouts for faster testing
+    arming_away_time: 50ms
+    arming_home_time: 50ms
+    arming_night_time: 50ms
+    pending_time: 50ms
+    trigger_time: 100ms
+    restore_mode: ALWAYS_DISARMED
+    binary_sensors:
+      - input: door_sensor
+        bypass_armed_home: false
+        bypass_armed_night: false
+        chime: false
+        trigger_mode: DELAYED
+      - input: chime_sensor
+        bypass_armed_home: true
+        bypass_armed_night: true
+        chime: true
+        trigger_mode: DELAYED
+    on_state:
+      - logger.log: "State changed"
+    on_disarmed:
+      - logger.log: "Alarm disarmed"
+    on_arming:
+      - logger.log: "Alarm arming"
+    on_armed_away:
+      - logger.log: "Alarm armed away"
+    on_armed_home:
+      - logger.log: "Alarm armed home"
+    on_armed_night:
+      - logger.log: "Alarm armed night"
+    on_pending:
+      - logger.log: "Alarm pending"
+    on_triggered:
+      - logger.log: "Alarm triggered"
+    on_cleared:
+      - logger.log: "Alarm cleared"
+    on_chime:
+      - logger.log: "Chime activated"
+    on_ready:
+      - logger.log: "Sensors ready state changed"
+
+api:
+  batch_delay: 0ms
diff --git a/tests/integration/test_alarm_control_panel_state_transitions.py b/tests/integration/test_alarm_control_panel_state_transitions.py
new file mode 100644
index 0000000000..2977ff56c2
--- /dev/null
+++ b/tests/integration/test_alarm_control_panel_state_transitions.py
@@ -0,0 +1,319 @@
+"""Integration test for alarm control panel state transitions."""
+
+from __future__ import annotations
+
+import asyncio
+import re
+
+import aioesphomeapi
+from aioesphomeapi import (
+    AlarmControlPanelCommand,
+    AlarmControlPanelEntityState,
+    AlarmControlPanelInfo,
+    AlarmControlPanelState,
+    SwitchInfo,
+)
+import pytest
+
+from .state_utils import InitialStateHelper
+from .types import APIClientConnectedFactory, RunCompiledFunction
+
+
+@pytest.mark.asyncio
+async def test_alarm_control_panel_state_transitions(
+    yaml_config: str,
+    run_compiled: RunCompiledFunction,
+    api_client_connected: APIClientConnectedFactory,
+) -> None:
+    """Test alarm control panel state transitions.
+
+    This comprehensive test verifies all state transitions and listener callbacks:
+
+    1. Basic arm/disarm sequences:
+       - DISARMED -> ARMING -> ARMED_AWAY -> DISARMED
+       - DISARMED -> ARMING -> ARMED_HOME -> DISARMED
+       - DISARMED -> ARMING -> ARMED_NIGHT -> DISARMED
+
+    2. Wrong code rejection
+
+    3. Sensor triggering while armed:
+       - ARMED_AWAY -> PENDING -> TRIGGERED (delayed sensor)
+       - TRIGGERED -> ARMED_AWAY (auto-reset after trigger_time, fires on_cleared)
+
+    4. Chime functionality:
+       - Sensor open while DISARMED triggers on_chime
+
+    5. Ready state:
+       - Sensor state changes trigger on_ready
+    """
+    loop = asyncio.get_running_loop()
+
+    # Track log messages for callback verification
+    log_lines: list[str] = []
+    chime_future: asyncio.Future[bool] = loop.create_future()
+    ready_futures: list[asyncio.Future[bool]] = []
+    cleared_future: asyncio.Future[bool] = loop.create_future()
+
+    # Patterns to match log output from callbacks
+    chime_pattern = re.compile(r"Chime activated")
+    ready_pattern = re.compile(r"Sensors ready state changed")
+    cleared_pattern = re.compile(r"Alarm cleared")
+
+    def on_log_line(line: str) -> None:
+        log_lines.append(line)
+        if not chime_future.done() and chime_pattern.search(line):
+            chime_future.set_result(True)
+        if ready_pattern.search(line):
+            # Create new future for each ready event
+            for fut in ready_futures:
+                if not fut.done():
+                    fut.set_result(True)
+                    break
+        if not cleared_future.done() and cleared_pattern.search(line):
+            cleared_future.set_result(True)
+
+    async with (
+        run_compiled(yaml_config, line_callback=on_log_line),
+        api_client_connected() as client,
+    ):
+        entities, _ = await client.list_entities_services()
+
+        # Find entities
+        alarm_info: AlarmControlPanelInfo | None = None
+        door_switch_info: SwitchInfo | None = None
+        chime_switch_info: SwitchInfo | None = None
+
+        for entity in entities:
+            if isinstance(entity, AlarmControlPanelInfo):
+                alarm_info = entity
+            elif isinstance(entity, SwitchInfo):
+                if entity.name == "Door Sensor Switch":
+                    door_switch_info = entity
+                elif entity.name == "Chime Sensor Switch":
+                    chime_switch_info = entity
+
+        assert alarm_info is not None, "Alarm control panel not found"
+        assert door_switch_info is not None, "Door sensor switch not found"
+        assert chime_switch_info is not None, "Chime sensor switch not found"
+
+        # Track state changes
+        states_received: list[AlarmControlPanelState] = []
+        state_event = asyncio.Event()
+
+        def on_state(state: aioesphomeapi.EntityState) -> None:
+            if (
+                isinstance(state, AlarmControlPanelEntityState)
+                and state.key == alarm_info.key
+            ):
+                states_received.append(state.state)
+                state_event.set()
+
+        # Use InitialStateHelper to handle initial state broadcast
+        initial_state_helper = InitialStateHelper(entities)
+        client.subscribe_states(initial_state_helper.on_state_wrapper(on_state))
+
+        # Wait for initial states from all entities
+        await initial_state_helper.wait_for_initial_states()
+
+        # Verify alarm panel started in DISARMED state
+        initial_alarm_state = initial_state_helper.initial_states.get(alarm_info.key)
+        assert initial_alarm_state is not None, "No initial alarm state received"
+        assert isinstance(initial_alarm_state, AlarmControlPanelEntityState)
+        assert initial_alarm_state.state == AlarmControlPanelState.DISARMED
+
+        # Helper to wait for specific state
+        async def wait_for_state(
+            expected: AlarmControlPanelState, timeout: float = 5.0
+        ) -> None:
+            deadline = loop.time() + timeout
+            while True:
+                remaining = deadline - loop.time()
+                if remaining <= 0:
+                    raise TimeoutError(
+                        f"Timeout waiting for state {expected}, "
+                        f"last state: {states_received[-1] if states_received else 'none'}"
+                    )
+                await asyncio.wait_for(state_event.wait(), timeout=remaining)
+                state_event.clear()
+                if states_received[-1] == expected:
+                    return
+
+        # ===== Test wrong code rejection =====
+        client.alarm_control_panel_command(
+            alarm_info.key,
+            AlarmControlPanelCommand.ARM_AWAY,
+            code="0000",  # Wrong code
+        )
+
+        # Should NOT transition - wait a bit and verify no state changes
+        with pytest.raises(asyncio.TimeoutError):
+            await asyncio.wait_for(state_event.wait(), timeout=0.5)
+        # No state changes should have occurred (list is empty)
+        assert len(states_received) == 0, f"Unexpected state changes: {states_received}"
+
+        # ===== Test ARM_AWAY sequence =====
+        client.alarm_control_panel_command(
+            alarm_info.key,
+            AlarmControlPanelCommand.ARM_AWAY,
+            code="1234",
+        )
+        await wait_for_state(AlarmControlPanelState.ARMING)
+        await wait_for_state(AlarmControlPanelState.ARMED_AWAY)
+
+        # Disarm
+        client.alarm_control_panel_command(
+            alarm_info.key,
+            AlarmControlPanelCommand.DISARM,
+            code="1234",
+        )
+        await wait_for_state(AlarmControlPanelState.DISARMED)
+
+        # ===== Test ARM_HOME sequence =====
+        client.alarm_control_panel_command(
+            alarm_info.key,
+            AlarmControlPanelCommand.ARM_HOME,
+            code="1234",
+        )
+        await wait_for_state(AlarmControlPanelState.ARMING)
+        await wait_for_state(AlarmControlPanelState.ARMED_HOME)
+
+        # Disarm
+        client.alarm_control_panel_command(
+            alarm_info.key,
+            AlarmControlPanelCommand.DISARM,
+            code="1234",
+        )
+        await wait_for_state(AlarmControlPanelState.DISARMED)
+
+        # ===== Test ARM_NIGHT sequence =====
+        client.alarm_control_panel_command(
+            alarm_info.key,
+            AlarmControlPanelCommand.ARM_NIGHT,
+            code="1234",
+        )
+        await wait_for_state(AlarmControlPanelState.ARMING)
+        await wait_for_state(AlarmControlPanelState.ARMED_NIGHT)
+
+        # Disarm
+        client.alarm_control_panel_command(
+            alarm_info.key,
+            AlarmControlPanelCommand.DISARM,
+            code="1234",
+        )
+        await wait_for_state(AlarmControlPanelState.DISARMED)
+
+        # Verify basic state sequence (initial DISARMED is handled by InitialStateHelper)
+        expected_states = [
+            AlarmControlPanelState.ARMING,  # Arm away
+            AlarmControlPanelState.ARMED_AWAY,
+            AlarmControlPanelState.DISARMED,
+            AlarmControlPanelState.ARMING,  # Arm home
+            AlarmControlPanelState.ARMED_HOME,
+            AlarmControlPanelState.DISARMED,
+            AlarmControlPanelState.ARMING,  # Arm night
+            AlarmControlPanelState.ARMED_NIGHT,
+            AlarmControlPanelState.DISARMED,
+        ]
+        assert states_received == expected_states, (
+            f"State sequence mismatch.\nExpected: {expected_states}\n"
+            f"Got: {states_received}"
+        )
+
+        # ===== Test PENDING -> TRIGGERED -> CLEARED sequence =====
+        # This tests on_pending, on_triggered, and on_cleared callbacks
+
+        # Arm away first
+        client.alarm_control_panel_command(
+            alarm_info.key,
+            AlarmControlPanelCommand.ARM_AWAY,
+            code="1234",
+        )
+        await wait_for_state(AlarmControlPanelState.ARMING)
+        await wait_for_state(AlarmControlPanelState.ARMED_AWAY)
+
+        # Trip the door sensor (delayed mode triggers PENDING first)
+        client.switch_command(door_switch_info.key, True)
+
+        # Should go to PENDING (delayed sensor)
+        await wait_for_state(AlarmControlPanelState.PENDING)
+
+        # Should go to TRIGGERED after pending_time (50ms)
+        await wait_for_state(AlarmControlPanelState.TRIGGERED)
+
+        # Close the sensor
+        client.switch_command(door_switch_info.key, False)
+
+        # Wait for trigger_time to expire and auto-reset (100ms)
+        # The alarm should go back to ARMED_AWAY after trigger_time
+        # This transition FROM TRIGGERED fires on_cleared
+        await wait_for_state(AlarmControlPanelState.ARMED_AWAY, timeout=2.0)
+
+        # Verify on_cleared was logged
+        try:
+            await asyncio.wait_for(cleared_future, timeout=1.0)
+        except TimeoutError:
+            pytest.fail(f"on_cleared callback not fired. Log lines: {log_lines[-20:]}")
+
+        # Disarm
+        client.alarm_control_panel_command(
+            alarm_info.key,
+            AlarmControlPanelCommand.DISARM,
+            code="1234",
+        )
+        await wait_for_state(AlarmControlPanelState.DISARMED)
+
+        # Verify trigger sequence was added
+        assert AlarmControlPanelState.PENDING in states_received
+        assert AlarmControlPanelState.TRIGGERED in states_received
+
+        # ===== Test chime (sensor open while disarmed) =====
+        # The chime_sensor has chime: true, so opening it while disarmed
+        # should trigger on_chime callback
+
+        # We're currently DISARMED - open the chime sensor
+        client.switch_command(chime_switch_info.key, True)
+
+        # Wait for chime callback to be logged
+        try:
+            await asyncio.wait_for(chime_future, timeout=2.0)
+        except TimeoutError:
+            pytest.fail(f"on_chime callback not fired. Log lines: {log_lines[-20:]}")
+
+        # Close the chime sensor
+        client.switch_command(chime_switch_info.key, False)
+
+        # ===== Test ready state changes =====
+        # Opening/closing sensors while disarmed affects ready state
+        # The on_ready callback fires when sensors_ready changes
+
+        # Set up futures for ready state changes
+        ready_future_1: asyncio.Future[bool] = loop.create_future()
+        ready_future_2: asyncio.Future[bool] = loop.create_future()
+        ready_futures.extend([ready_future_1, ready_future_2])
+
+        # Open door sensor (makes alarm not ready)
+        client.switch_command(door_switch_info.key, True)
+
+        # Wait for first on_ready callback (not ready)
+        try:
+            await asyncio.wait_for(ready_future_1, timeout=2.0)
+        except TimeoutError:
+            pytest.fail(
+                f"on_ready callback not fired when sensor opened. "
+                f"Log lines: {log_lines[-20:]}"
+            )
+
+        # Close door sensor (makes alarm ready again)
+        client.switch_command(door_switch_info.key, False)
+
+        # Wait for second on_ready callback (ready)
+        try:
+            await asyncio.wait_for(ready_future_2, timeout=2.0)
+        except TimeoutError:
+            pytest.fail(
+                f"on_ready callback not fired when sensor closed. "
+                f"Log lines: {log_lines[-20:]}"
+            )
+
+        # Final state should still be DISARMED
+        assert states_received[-1] == AlarmControlPanelState.DISARMED

From c9fccdff251ae4a796d1123c656afe1ac9490631 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@koston.org>
Date: Fri, 19 Dec 2025 12:05:52 -1000
Subject: [PATCH 7/7] [fan] Add zero-copy support for API preset mode commands
 (#12404)

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
---
 esphome/components/api/api.proto          |  2 +-
 esphome/components/api/api_connection.cpp |  2 +-
 esphome/components/api/api_pb2.cpp        |  7 +++++--
 esphome/components/api/api_pb2.h          |  5 +++--
 esphome/components/api/api_pb2_dump.cpp   |  4 +++-
 esphome/components/fan/fan.cpp            | 22 +++++++++++++++++-----
 esphome/components/fan/fan.h              |  2 ++
 esphome/components/fan/fan_traits.h       |  7 +++++--
 8 files changed, 37 insertions(+), 14 deletions(-)

diff --git a/esphome/components/api/api.proto b/esphome/components/api/api.proto
index dd8320bebb..e8c900df26 100644
--- a/esphome/components/api/api.proto
+++ b/esphome/components/api/api.proto
@@ -477,7 +477,7 @@ message FanCommandRequest {
   bool has_speed_level = 10;
   int32 speed_level = 11;
   bool has_preset_mode = 12;
-  string preset_mode = 13;
+  string preset_mode = 13 [(pointer_to_buffer) = true];
   uint32 device_id = 14 [(field_ifdef) = "USE_DEVICES"];
 }
 
diff --git a/esphome/components/api/api_connection.cpp b/esphome/components/api/api_connection.cpp
index 686fdcba41..126d3cb220 100644
--- a/esphome/components/api/api_connection.cpp
+++ b/esphome/components/api/api_connection.cpp
@@ -447,7 +447,7 @@ void APIConnection::fan_command(const FanCommandRequest &msg) {
   if (msg.has_direction)
     call.set_direction(static_cast<fan::FanDirection>(msg.direction));
   if (msg.has_preset_mode)
-    call.set_preset_mode(msg.preset_mode);
+    call.set_preset_mode(reinterpret_cast<const char *>(msg.preset_mode), msg.preset_mode_len);
   call.perform();
 }
 #endif
diff --git a/esphome/components/api/api_pb2.cpp b/esphome/components/api/api_pb2.cpp
index 211f856e3b..8bba13a4de 100644
--- a/esphome/components/api/api_pb2.cpp
+++ b/esphome/components/api/api_pb2.cpp
@@ -447,9 +447,12 @@ bool FanCommandRequest::decode_varint(uint32_t field_id, ProtoVarInt value) {
 }
 bool FanCommandRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
-    case 13:
-      this->preset_mode = value.as_string();
+    case 13: {
+      // Use raw data directly to avoid allocation
+      this->preset_mode = value.data();
+      this->preset_mode_len = value.size();
       break;
+    }
     default:
       return false;
   }
diff --git a/esphome/components/api/api_pb2.h b/esphome/components/api/api_pb2.h
index 4e10c63881..d3b91ac56b 100644
--- a/esphome/components/api/api_pb2.h
+++ b/esphome/components/api/api_pb2.h
@@ -765,7 +765,7 @@ class FanStateResponse final : public StateResponseProtoMessage {
 class FanCommandRequest final : public CommandProtoMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 31;
-  static constexpr uint8_t ESTIMATED_SIZE = 38;
+  static constexpr uint8_t ESTIMATED_SIZE = 48;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "fan_command_request"; }
 #endif
@@ -778,7 +778,8 @@ class FanCommandRequest final : public CommandProtoMessage {
   bool has_speed_level{false};
   int32_t speed_level{0};
   bool has_preset_mode{false};
-  std::string preset_mode{};
+  const uint8_t *preset_mode{nullptr};
+  uint16_t preset_mode_len{0};
 #ifdef HAS_PROTO_MESSAGE_DUMP
   void dump_to(std::string &out) const override;
 #endif
diff --git a/esphome/components/api/api_pb2_dump.cpp b/esphome/components/api/api_pb2_dump.cpp
index 90e8e75c93..d733e66a6d 100644
--- a/esphome/components/api/api_pb2_dump.cpp
+++ b/esphome/components/api/api_pb2_dump.cpp
@@ -923,7 +923,9 @@ void FanCommandRequest::dump_to(std::string &out) const {
   dump_field(out, "has_speed_level", this->has_speed_level);
   dump_field(out, "speed_level", this->speed_level);
   dump_field(out, "has_preset_mode", this->has_preset_mode);
-  dump_field(out, "preset_mode", this->preset_mode);
+  out.append("  preset_mode: ");
+  out.append(format_hex_pretty(this->preset_mode, this->preset_mode_len));
+  out.append("\n");
 #ifdef USE_DEVICES
   dump_field(out, "device_id", this->device_id);
 #endif
diff --git a/esphome/components/fan/fan.cpp b/esphome/components/fan/fan.cpp
index d37825a651..bf5506da4b 100644
--- a/esphome/components/fan/fan.cpp
+++ b/esphome/components/fan/fan.cpp
@@ -19,22 +19,28 @@ const LogString *fan_direction_to_string(FanDirection direction) {
   }
 }
 
-FanCall &FanCall::set_preset_mode(const std::string &preset_mode) { return this->set_preset_mode(preset_mode.c_str()); }
+FanCall &FanCall::set_preset_mode(const std::string &preset_mode) {
+  return this->set_preset_mode(preset_mode.data(), preset_mode.size());
+}
 
 FanCall &FanCall::set_preset_mode(const char *preset_mode) {
-  if (preset_mode == nullptr || strlen(preset_mode) == 0) {
+  return this->set_preset_mode(preset_mode, preset_mode ? strlen(preset_mode) : 0);
+}
+
+FanCall &FanCall::set_preset_mode(const char *preset_mode, size_t len) {
+  if (preset_mode == nullptr || len == 0) {
     this->preset_mode_ = nullptr;
     return *this;
   }
 
   // Find and validate pointer from traits immediately
   auto traits = this->parent_.get_traits();
-  const char *validated_mode = traits.find_preset_mode(preset_mode);
+  const char *validated_mode = traits.find_preset_mode(preset_mode, len);
   if (validated_mode != nullptr) {
     this->preset_mode_ = validated_mode;  // Store pointer from traits
   } else {
     // Preset mode not found in traits - log warning and don't set
-    ESP_LOGW(TAG, "%s: Preset mode '%s' not supported", this->parent_.get_name().c_str(), preset_mode);
+    ESP_LOGW(TAG, "%s: Preset mode '%.*s' not supported", this->parent_.get_name().c_str(), (int) len, preset_mode);
     this->preset_mode_ = nullptr;
   }
   return *this;
@@ -140,7 +146,13 @@ FanCall Fan::turn_off() { return this->make_call().set_state(false); }
 FanCall Fan::toggle() { return this->make_call().set_state(!this->state); }
 FanCall Fan::make_call() { return FanCall(*this); }
 
-const char *Fan::find_preset_mode_(const char *preset_mode) { return this->get_traits().find_preset_mode(preset_mode); }
+const char *Fan::find_preset_mode_(const char *preset_mode) {
+  return this->find_preset_mode_(preset_mode, preset_mode ? strlen(preset_mode) : 0);
+}
+
+const char *Fan::find_preset_mode_(const char *preset_mode, size_t len) {
+  return this->get_traits().find_preset_mode(preset_mode, len);
+}
 
 bool Fan::set_preset_mode_(const char *preset_mode) {
   if (preset_mode == nullptr) {
diff --git a/esphome/components/fan/fan.h b/esphome/components/fan/fan.h
index e38a80dbbe..70c4dab940 100644
--- a/esphome/components/fan/fan.h
+++ b/esphome/components/fan/fan.h
@@ -72,6 +72,7 @@ class FanCall {
   optional<FanDirection> get_direction() const { return this->direction_; }
   FanCall &set_preset_mode(const std::string &preset_mode);
   FanCall &set_preset_mode(const char *preset_mode);
+  FanCall &set_preset_mode(const char *preset_mode, size_t len);
   const char *get_preset_mode() const { return this->preset_mode_; }
   bool has_preset_mode() const { return this->preset_mode_ != nullptr; }
 
@@ -152,6 +153,7 @@ class Fan : public EntityBase {
   void clear_preset_mode_();
   /// Find and return the matching preset mode pointer from traits, or nullptr if not found.
   const char *find_preset_mode_(const char *preset_mode);
+  const char *find_preset_mode_(const char *preset_mode, size_t len);
 
   CallbackManager<void()> state_callback_{};
   ESPPreferenceObject rtc_;
diff --git a/esphome/components/fan/fan_traits.h b/esphome/components/fan/fan_traits.h
index 24987fe984..c0c5f34c50 100644
--- a/esphome/components/fan/fan_traits.h
+++ b/esphome/components/fan/fan_traits.h
@@ -47,10 +47,13 @@ class FanTraits {
   bool supports_preset_modes() const { return !this->preset_modes_.empty(); }
   /// Find and return the matching preset mode pointer from supported modes, or nullptr if not found.
   const char *find_preset_mode(const char *preset_mode) const {
-    if (preset_mode == nullptr)
+    return this->find_preset_mode(preset_mode, preset_mode ? strlen(preset_mode) : 0);
+  }
+  const char *find_preset_mode(const char *preset_mode, size_t len) const {
+    if (preset_mode == nullptr || len == 0)
       return nullptr;
     for (const char *mode : this->preset_modes_) {
-      if (strcmp(mode, preset_mode) == 0) {
+      if (strncmp(mode, preset_mode, len) == 0 && mode[len] == '\0') {
         return mode;  // Return pointer from traits
       }
     }