Merge remote-tracking branch 'upstream/dev' into no_new_to_string

# Conflicts:
#	script/ci-custom.py

.clang-tidy.hash

@@ -1 +1 @@
-d272a88e8ca28ae9340a9a03295a566432a52cb696501908f57764475bf7ca65
+15dc295268b2dcf75942f42759b3ddec64eba89f75525698eb39c95a7f4b14ce

.github/workflows/sync-device-classes.yml

@@ -41,7 +41,7 @@ jobs:
           python script/run-in-env.py pre-commit run --all-files
 
       - name: Commit changes
-        uses: peter-evans/create-pull-request@98357b18bf14b5342f975ff684046ec3b2a07725 # v8.0.0
+        uses: peter-evans/create-pull-request@c0f553fe549906ede9cf27b5156039d195d2ece0 # v8.1.0
         with:
           commit-message: "Synchronise Device Classes from Home Assistant"
           committer: esphomebot <esphome@openhomefoundation.org>

esphome/__main__.py

@@ -43,6 +43,7 @@ from esphome.const import (
     CONF_SUBSTITUTIONS,
     CONF_TOPIC,
     ENV_NOGITIGNORE,
+    KEY_NATIVE_IDF,
     PLATFORM_ESP32,
     PLATFORM_ESP8266,
     PLATFORM_RP2040,
@@ -116,6 +117,7 @@ class ArgsProtocol(Protocol):
     configuration: str
     name: str
     upload_speed: str | None
+    native_idf: bool
 
 
 def choose_prompt(options, purpose: str = None):
@@ -500,12 +502,15 @@ def wrap_to_code(name, comp):
     return wrapped
 
 
-def write_cpp(config: ConfigType) -> int:
+def write_cpp(config: ConfigType, native_idf: bool = False) -> int:
     if not get_bool_env(ENV_NOGITIGNORE):
         writer.write_gitignore()
 
+    # Store native_idf flag so esp32 component can check it
+    CORE.data[KEY_NATIVE_IDF] = native_idf
+
     generate_cpp_contents(config)
-    return write_cpp_file()
+    return write_cpp_file(native_idf=native_idf)
 
 
 def generate_cpp_contents(config: ConfigType) -> None:
@@ -519,32 +524,54 @@ def generate_cpp_contents(config: ConfigType) -> None:
     CORE.flush_tasks()
 
 
-def write_cpp_file() -> int:
+def write_cpp_file(native_idf: bool = False) -> int:
     code_s = indent(CORE.cpp_main_section)
     writer.write_cpp(code_s)
 
-    from esphome.build_gen import platformio
+    if native_idf and CORE.is_esp32 and CORE.target_framework == "esp-idf":
+        from esphome.build_gen import espidf
 
-    platformio.write_project()
+        espidf.write_project()
+    else:
+        from esphome.build_gen import platformio
+
+        platformio.write_project()
 
     return 0
 
 
 def compile_program(args: ArgsProtocol, config: ConfigType) -> int:
-    from esphome import platformio_api
+    native_idf = getattr(args, "native_idf", False)
 
     # NOTE: "Build path:" format is parsed by script/ci_memory_impact_extract.py
     # If you change this format, update the regex in that script as well
     _LOGGER.info("Compiling app... Build path: %s", CORE.build_path)
-    rc = platformio_api.run_compile(config, CORE.verbose)
-    if rc != 0:
-        return rc
+
+    if native_idf and CORE.is_esp32 and CORE.target_framework == "esp-idf":
+        from esphome import espidf_api
+
+        rc = espidf_api.run_compile(config, CORE.verbose)
+        if rc != 0:
+            return rc
+
+        # Create factory.bin and ota.bin
+        espidf_api.create_factory_bin()
+        espidf_api.create_ota_bin()
+    else:
+        from esphome import platformio_api
+
+        rc = platformio_api.run_compile(config, CORE.verbose)
+        if rc != 0:
+            return rc
+
+        idedata = platformio_api.get_idedata(config)
+        if idedata is None:
+            return 1
 
     # Check if firmware was rebuilt and emit build_info + create manifest
     _check_and_emit_build_info()
 
-    idedata = platformio_api.get_idedata(config)
-    return 0 if idedata is not None else 1
+    return 0
 
 
 def _check_and_emit_build_info() -> None:
@@ -801,7 +828,8 @@ def command_vscode(args: ArgsProtocol) -> int | None:
 
 
 def command_compile(args: ArgsProtocol, config: ConfigType) -> int | None:
-    exit_code = write_cpp(config)
+    native_idf = getattr(args, "native_idf", False)
+    exit_code = write_cpp(config, native_idf=native_idf)
     if exit_code != 0:
         return exit_code
     if args.only_generate:
@@ -856,7 +884,8 @@ def command_logs(args: ArgsProtocol, config: ConfigType) -> int | None:
 
 
 def command_run(args: ArgsProtocol, config: ConfigType) -> int | None:
-    exit_code = write_cpp(config)
+    native_idf = getattr(args, "native_idf", False)
+    exit_code = write_cpp(config, native_idf=native_idf)
     if exit_code != 0:
         return exit_code
     exit_code = compile_program(args, config)
@@ -1310,6 +1339,11 @@ def parse_args(argv):
         help="Only generate source code, do not compile.",
         action="store_true",
     )
+    parser_compile.add_argument(
+        "--native-idf",
+        help="Build with native ESP-IDF instead of PlatformIO (ESP32 esp-idf framework only).",
+        action="store_true",
+    )
 
     parser_upload = subparsers.add_parser(
         "upload",
@@ -1391,6 +1425,11 @@ def parse_args(argv):
         help="Reset the device before starting serial logs.",
         default=os.getenv("ESPHOME_SERIAL_LOGGING_RESET"),
     )
+    parser_run.add_argument(
+        "--native-idf",
+        help="Build with native ESP-IDF instead of PlatformIO (ESP32 esp-idf framework only).",
+        action="store_true",
+    )
 
     parser_clean = subparsers.add_parser(
         "clean-mqtt",

esphome/build_gen/espidf.py

@@ -0,0 +1,139 @@
+"""ESP-IDF direct build generator for ESPHome."""
+
+import json
+from pathlib import Path
+
+from esphome.components.esp32 import get_esp32_variant
+from esphome.core import CORE
+from esphome.helpers import mkdir_p, write_file_if_changed
+
+
+def get_available_components() -> list[str] | None:
+    """Get list of available ESP-IDF components from project_description.json.
+
+    Returns only internal ESP-IDF components, excluding external/managed
+    components (from idf_component.yml).
+    """
+    project_desc = Path(CORE.build_path) / "build" / "project_description.json"
+    if not project_desc.exists():
+        return None
+
+    try:
+        with open(project_desc, encoding="utf-8") as f:
+            data = json.load(f)
+
+        component_info = data.get("build_component_info", {})
+
+        result = []
+        for name, info in component_info.items():
+            # Exclude our own src component
+            if name == "src":
+                continue
+
+            # Exclude managed/external components
+            comp_dir = info.get("dir", "")
+            if "managed_components" in comp_dir:
+                continue
+
+            result.append(name)
+
+        return result
+    except (json.JSONDecodeError, OSError):
+        return None
+
+
+def has_discovered_components() -> bool:
+    """Check if we have discovered components from a previous configure."""
+    return get_available_components() is not None
+
+
+def get_project_cmakelists() -> str:
+    """Generate the top-level CMakeLists.txt for ESP-IDF project."""
+    # Get IDF target from ESP32 variant (e.g., ESP32S3 -> esp32s3)
+    variant = get_esp32_variant()
+    idf_target = variant.lower().replace("-", "")
+
+    return f"""\
+# Auto-generated by ESPHome
+cmake_minimum_required(VERSION 3.16)
+
+set(IDF_TARGET {idf_target})
+set(EXTRA_COMPONENT_DIRS ${{CMAKE_SOURCE_DIR}}/src)
+
+include($ENV{{IDF_PATH}}/tools/cmake/project.cmake)
+project({CORE.name})
+"""
+
+
+def get_component_cmakelists(minimal: bool = False) -> str:
+    """Generate the main component CMakeLists.txt."""
+    idf_requires = [] if minimal else (get_available_components() or [])
+    requires_str = " ".join(idf_requires)
+
+    # Extract compile definitions from build flags (-DXXX -> XXX)
+    compile_defs = [flag[2:] for flag in CORE.build_flags if flag.startswith("-D")]
+    compile_defs_str = "\n    ".join(compile_defs) if compile_defs else ""
+
+    # Extract compile options (-W flags, excluding linker flags)
+    compile_opts = [
+        flag
+        for flag in CORE.build_flags
+        if flag.startswith("-W") and not flag.startswith("-Wl,")
+    ]
+    compile_opts_str = "\n    ".join(compile_opts) if compile_opts else ""
+
+    # Extract linker options (-Wl, flags)
+    link_opts = [flag for flag in CORE.build_flags if flag.startswith("-Wl,")]
+    link_opts_str = "\n    ".join(link_opts) if link_opts else ""
+
+    return f"""\
+# Auto-generated by ESPHome
+file(GLOB_RECURSE app_sources
+    "${{CMAKE_CURRENT_SOURCE_DIR}}/*.cpp"
+    "${{CMAKE_CURRENT_SOURCE_DIR}}/*.c"
+    "${{CMAKE_CURRENT_SOURCE_DIR}}/esphome/*.cpp"
+    "${{CMAKE_CURRENT_SOURCE_DIR}}/esphome/*.c"
+)
+
+idf_component_register(
+    SRCS ${{app_sources}}
+    INCLUDE_DIRS "." "esphome"
+    REQUIRES {requires_str}
+)
+
+# Apply C++ standard
+target_compile_features(${{COMPONENT_LIB}} PUBLIC cxx_std_20)
+
+# ESPHome compile definitions
+target_compile_definitions(${{COMPONENT_LIB}} PUBLIC
+    {compile_defs_str}
+)
+
+# ESPHome compile options
+target_compile_options(${{COMPONENT_LIB}} PUBLIC
+    {compile_opts_str}
+)
+
+# ESPHome linker options
+target_link_options(${{COMPONENT_LIB}} PUBLIC
+    {link_opts_str}
+)
+"""
+
+
+def write_project(minimal: bool = False) -> None:
+    """Write ESP-IDF project files."""
+    mkdir_p(CORE.build_path)
+    mkdir_p(CORE.relative_src_path())
+
+    # Write top-level CMakeLists.txt
+    write_file_if_changed(
+        CORE.relative_build_path("CMakeLists.txt"),
+        get_project_cmakelists(),
+    )
+
+    # Write component CMakeLists.txt in src/
+    write_file_if_changed(
+        CORE.relative_src_path("CMakeLists.txt"),
+        get_component_cmakelists(minimal=minimal),
+    )

esphome/components/adc/sensor.py

@@ -160,21 +160,21 @@ async def to_code(config):
         zephyr_add_user("io-channels", f"<&adc {channel_id}>")
         zephyr_add_overlay(
             f"""
-&adc {{
-    #address-cells = <1>;
-    #size-cells = <0>;
+                &adc {{
+                    #address-cells = <1>;
+                    #size-cells = <0>;
 
-    channel@{channel_id} {{
-        reg = <{channel_id}>;
-        zephyr,gain = "{gain}";
-        zephyr,reference = "ADC_REF_INTERNAL";
-        zephyr,acquisition-time = <ADC_ACQ_TIME_DEFAULT>;
-        zephyr,input-positive = <NRF_SAADC_{pin_number}>;
-        zephyr,resolution = <14>;
-        zephyr,oversampling = <8>;
-    }};
-}};
-"""
+                    channel@{channel_id} {{
+                        reg = <{channel_id}>;
+                        zephyr,gain = "{gain}";
+                        zephyr,reference = "ADC_REF_INTERNAL";
+                        zephyr,acquisition-time = <ADC_ACQ_TIME_DEFAULT>;
+                        zephyr,input-positive = <NRF_SAADC_{pin_number}>;
+                        zephyr,resolution = <14>;
+                        zephyr,oversampling = <8>;
+                    }};
+                }};
+            """
         )
 
 

esphome/components/alarm_control_panel/alarm_control_panel.cpp

@@ -67,52 +67,29 @@ void AlarmControlPanel::add_on_ready_callback(std::function<void()> &&callback)
   this->ready_callback_.add(std::move(callback));
 }
 
-void AlarmControlPanel::arm_away(optional<std::string> code) {
+void AlarmControlPanel::arm_with_code_(AlarmControlPanelCall &(AlarmControlPanelCall::*arm_method)(),
+                                       const char *code) {
   auto call = this->make_call();
-  call.arm_away();
-  if (code.has_value())
-    call.set_code(code.value());
+  (call.*arm_method)();
+  if (code != nullptr)
+    call.set_code(code);
   call.perform();
 }
 
-void AlarmControlPanel::arm_home(optional<std::string> code) {
-  auto call = this->make_call();
-  call.arm_home();
-  if (code.has_value())
-    call.set_code(code.value());
-  call.perform();
+void AlarmControlPanel::arm_away(const char *code) { this->arm_with_code_(&AlarmControlPanelCall::arm_away, code); }
+
+void AlarmControlPanel::arm_home(const char *code) { this->arm_with_code_(&AlarmControlPanelCall::arm_home, code); }
+
+void AlarmControlPanel::arm_night(const char *code) { this->arm_with_code_(&AlarmControlPanelCall::arm_night, code); }
+
+void AlarmControlPanel::arm_vacation(const char *code) {
+  this->arm_with_code_(&AlarmControlPanelCall::arm_vacation, code);
 }
 
-void AlarmControlPanel::arm_night(optional<std::string> code) {
-  auto call = this->make_call();
-  call.arm_night();
-  if (code.has_value())
-    call.set_code(code.value());
-  call.perform();
+void AlarmControlPanel::arm_custom_bypass(const char *code) {
+  this->arm_with_code_(&AlarmControlPanelCall::arm_custom_bypass, code);
 }
 
-void AlarmControlPanel::arm_vacation(optional<std::string> code) {
-  auto call = this->make_call();
-  call.arm_vacation();
-  if (code.has_value())
-    call.set_code(code.value());
-  call.perform();
-}
-
-void AlarmControlPanel::arm_custom_bypass(optional<std::string> code) {
-  auto call = this->make_call();
-  call.arm_custom_bypass();
-  if (code.has_value())
-    call.set_code(code.value());
-  call.perform();
-}
-
-void AlarmControlPanel::disarm(optional<std::string> code) {
-  auto call = this->make_call();
-  call.disarm();
-  if (code.has_value())
-    call.set_code(code.value());
-  call.perform();
-}
+void AlarmControlPanel::disarm(const char *code) { this->arm_with_code_(&AlarmControlPanelCall::disarm, code); }
 
 }  // namespace esphome::alarm_control_panel

esphome/components/alarm_control_panel/alarm_control_panel.h

@@ -76,37 +76,53 @@ class AlarmControlPanel : public EntityBase {
    *
    * @param code The code
    */
-  void arm_away(optional<std::string> code = nullopt);
+  void arm_away(const char *code = nullptr);
+  void arm_away(const optional<std::string> &code) {
+    this->arm_away(code.has_value() ? code.value().c_str() : nullptr);
+  }
 
   /** arm the alarm in home mode
    *
    * @param code The code
    */
-  void arm_home(optional<std::string> code = nullopt);
+  void arm_home(const char *code = nullptr);
+  void arm_home(const optional<std::string> &code) {
+    this->arm_home(code.has_value() ? code.value().c_str() : nullptr);
+  }
 
   /** arm the alarm in night mode
    *
    * @param code The code
    */
-  void arm_night(optional<std::string> code = nullopt);
+  void arm_night(const char *code = nullptr);
+  void arm_night(const optional<std::string> &code) {
+    this->arm_night(code.has_value() ? code.value().c_str() : nullptr);
+  }
 
   /** arm the alarm in vacation mode
    *
    * @param code The code
    */
-  void arm_vacation(optional<std::string> code = nullopt);
+  void arm_vacation(const char *code = nullptr);
+  void arm_vacation(const optional<std::string> &code) {
+    this->arm_vacation(code.has_value() ? code.value().c_str() : nullptr);
+  }
 
   /** arm the alarm in custom bypass mode
    *
    * @param code The code
    */
-  void arm_custom_bypass(optional<std::string> code = nullopt);
+  void arm_custom_bypass(const char *code = nullptr);
+  void arm_custom_bypass(const optional<std::string> &code) {
+    this->arm_custom_bypass(code.has_value() ? code.value().c_str() : nullptr);
+  }
 
   /** disarm the alarm
    *
    * @param code The code
    */
-  void disarm(optional<std::string> code = nullopt);
+  void disarm(const char *code = nullptr);
+  void disarm(const optional<std::string> &code) { this->disarm(code.has_value() ? code.value().c_str() : nullptr); }
 
   /** Get the state
    *
@@ -118,6 +134,8 @@ class AlarmControlPanel : public EntityBase {
 
  protected:
   friend AlarmControlPanelCall;
+  // Helper to reduce code duplication for arm/disarm methods
+  void arm_with_code_(AlarmControlPanelCall &(AlarmControlPanelCall::*arm_method)(), const char *code);
   // in order to store last panel state in flash
   ESPPreferenceObject pref_;
   // current state

esphome/components/alarm_control_panel/alarm_control_panel_call.cpp

@@ -10,8 +10,10 @@ static const char *const TAG = "alarm_control_panel";
 
 AlarmControlPanelCall::AlarmControlPanelCall(AlarmControlPanel *parent) : parent_(parent) {}
 
-AlarmControlPanelCall &AlarmControlPanelCall::set_code(const std::string &code) {
-  this->code_ = code;
+AlarmControlPanelCall &AlarmControlPanelCall::set_code(const char *code) {
+  if (code != nullptr) {
+    this->code_ = std::string(code);
+  }
   return *this;
 }
 

esphome/components/alarm_control_panel/alarm_control_panel_call.h

@@ -14,7 +14,8 @@ class AlarmControlPanelCall {
  public:
   AlarmControlPanelCall(AlarmControlPanel *parent);
 
-  AlarmControlPanelCall &set_code(const std::string &code);
+  AlarmControlPanelCall &set_code(const char *code);
+  AlarmControlPanelCall &set_code(const std::string &code) { return this->set_code(code.c_str()); }
   AlarmControlPanelCall &arm_away();
   AlarmControlPanelCall &arm_home();
   AlarmControlPanelCall &arm_night();

esphome/components/alarm_control_panel/automation.h

@@ -66,15 +66,7 @@ template<typename... Ts> class ArmAwayAction : public Action<Ts...> {
 
   TEMPLATABLE_VALUE(std::string, code)
 
-  void play(const Ts &...x) override {
-    auto call = this->alarm_control_panel_->make_call();
-    auto code = this->code_.optional_value(x...);
-    if (code.has_value()) {
-      call.set_code(code.value());
-    }
-    call.arm_away();
-    call.perform();
-  }
+  void play(const Ts &...x) override { this->alarm_control_panel_->arm_away(this->code_.optional_value(x...)); }
 
  protected:
   AlarmControlPanel *alarm_control_panel_;
@@ -86,15 +78,7 @@ template<typename... Ts> class ArmHomeAction : public Action<Ts...> {
 
   TEMPLATABLE_VALUE(std::string, code)
 
-  void play(const Ts &...x) override {
-    auto call = this->alarm_control_panel_->make_call();
-    auto code = this->code_.optional_value(x...);
-    if (code.has_value()) {
-      call.set_code(code.value());
-    }
-    call.arm_home();
-    call.perform();
-  }
+  void play(const Ts &...x) override { this->alarm_control_panel_->arm_home(this->code_.optional_value(x...)); }
 
  protected:
   AlarmControlPanel *alarm_control_panel_;
@@ -106,15 +90,7 @@ template<typename... Ts> class ArmNightAction : public Action<Ts...> {
 
   TEMPLATABLE_VALUE(std::string, code)
 
-  void play(const Ts &...x) override {
-    auto call = this->alarm_control_panel_->make_call();
-    auto code = this->code_.optional_value(x...);
-    if (code.has_value()) {
-      call.set_code(code.value());
-    }
-    call.arm_night();
-    call.perform();
-  }
+  void play(const Ts &...x) override { this->alarm_control_panel_->arm_night(this->code_.optional_value(x...)); }
 
  protected:
   AlarmControlPanel *alarm_control_panel_;

esphome/components/api/api_frame_helper_noise.cpp

@@ -3,6 +3,7 @@
 #ifdef USE_API_NOISE
 #include "api_connection.h"  // For ClientInfo struct
 #include "esphome/core/application.h"
+#include "esphome/core/entity_base.h"
 #include "esphome/core/hal.h"
 #include "esphome/core/helpers.h"
 #include "esphome/core/log.h"
@@ -256,28 +257,30 @@ APIError APINoiseFrameHelper::state_action_() {
   }
   if (state_ == State::SERVER_HELLO) {
     // send server hello
-    constexpr size_t mac_len = 13;  // 12 hex chars + null terminator
     const std::string &name = App.get_name();
-    char mac[mac_len];
+    char mac[MAC_ADDRESS_BUFFER_SIZE];
     get_mac_address_into_buffer(mac);
 
     // Calculate positions and sizes
     size_t name_len = name.size() + 1;  // including null terminator
     size_t name_offset = 1;
     size_t mac_offset = name_offset + name_len;
-    size_t total_size = 1 + name_len + mac_len;
+    size_t total_size = 1 + name_len + MAC_ADDRESS_BUFFER_SIZE;
 
-    auto msg = std::make_unique<uint8_t[]>(total_size);
+    // 1 (proto) + name (max ESPHOME_DEVICE_NAME_MAX_LEN) + 1 (name null)
+    // + mac (MAC_ADDRESS_BUFFER_SIZE - 1) + 1 (mac null)
+    constexpr size_t max_msg_size = 1 + ESPHOME_DEVICE_NAME_MAX_LEN + 1 + MAC_ADDRESS_BUFFER_SIZE;
+    uint8_t msg[max_msg_size];
 
     // chosen proto
     msg[0] = 0x01;
 
     // node name, terminated by null byte
-    std::memcpy(msg.get() + name_offset, name.c_str(), name_len);
+    std::memcpy(msg + name_offset, name.c_str(), name_len);
     // node mac, terminated by null byte
-    std::memcpy(msg.get() + mac_offset, mac, mac_len);
+    std::memcpy(msg + mac_offset, mac, MAC_ADDRESS_BUFFER_SIZE);
 
-    aerr = write_frame_(msg.get(), total_size);
+    aerr = write_frame_(msg, total_size);
     if (aerr != APIError::OK)
       return aerr;
 
@@ -353,35 +356,32 @@ APIError APINoiseFrameHelper::state_action_() {
   return APIError::OK;
 }
 void APINoiseFrameHelper::send_explicit_handshake_reject_(const LogString *reason) {
+  // Max reject message: "Bad handshake packet len" (24) + 1 (failure byte) = 25 bytes
+  uint8_t data[32];
+  data[0] = 0x01;  // failure
+
 #ifdef USE_STORE_LOG_STR_IN_FLASH
   // On ESP8266 with flash strings, we need to use PROGMEM-aware functions
   size_t reason_len = strlen_P(reinterpret_cast<PGM_P>(reason));
-  size_t data_size = reason_len + 1;
-  auto data = std::make_unique<uint8_t[]>(data_size);
-  data[0] = 0x01;  // failure
-
-  // Copy error message from PROGMEM
   if (reason_len > 0) {
-    memcpy_P(data.get() + 1, reinterpret_cast<PGM_P>(reason), reason_len);
+    memcpy_P(data + 1, reinterpret_cast<PGM_P>(reason), reason_len);
   }
 #else
   // Normal memory access
   const char *reason_str = LOG_STR_ARG(reason);
   size_t reason_len = strlen(reason_str);
-  size_t data_size = reason_len + 1;
-  auto data = std::make_unique<uint8_t[]>(data_size);
-  data[0] = 0x01;  // failure
-
-  // Copy error message in bulk
   if (reason_len > 0) {
-    std::memcpy(data.get() + 1, reason_str, reason_len);
+    // NOLINTNEXTLINE(bugprone-not-null-terminated-result) - binary protocol, not a C string
+    std::memcpy(data + 1, reason_str, reason_len);
   }
 #endif
 
+  size_t data_size = reason_len + 1;
+
   // temporarily remove failed state
   auto orig_state = state_;
   state_ = State::EXPLICIT_REJECT;
-  write_frame_(data.get(), data_size);
+  write_frame_(data, data_size);
   state_ = orig_state;
 }
 APIError APINoiseFrameHelper::read_packet(ReadPacketBuffer *buffer) {

esphome/components/audio/__init__.py

@@ -1,4 +1,5 @@
 import esphome.codegen as cg
+from esphome.components.esp32 import add_idf_component
 import esphome.config_validation as cv
 from esphome.const import CONF_BITS_PER_SAMPLE, CONF_NUM_CHANNELS, CONF_SAMPLE_RATE
 import esphome.final_validate as fv
@@ -165,4 +166,7 @@ def final_validate_audio_schema(
 
 
 async def to_code(config):
-    cg.add_library("esphome/esp-audio-libs", "2.0.1")
+    add_idf_component(
+        name="esphome/esp-audio-libs",
+        ref="2.0.3",
+    )

esphome/components/audio/audio_decoder.cpp

@@ -300,7 +300,7 @@ FileDecoderState AudioDecoder::decode_mp3_() {
 
   // Advance read pointer to match the offset for the syncword
   this->input_transfer_buffer_->decrease_buffer_length(offset);
-  uint8_t *buffer_start = this->input_transfer_buffer_->get_buffer_start();
+  const uint8_t *buffer_start = this->input_transfer_buffer_->get_buffer_start();
 
   buffer_length = (int) this->input_transfer_buffer_->available();
   int err = esp_audio_libs::helix_decoder::MP3Decode(this->mp3_decoder_, &buffer_start, &buffer_length,

esphome/components/bluetooth_proxy/bluetooth_connection.cpp

@@ -135,8 +135,8 @@ void BluetoothConnection::loop() {
   // - For V3_WITH_CACHE: Services are never sent, disable after INIT state
   // - For V3_WITHOUT_CACHE: Disable only after service discovery is complete
   //   (send_service_ == DONE_SENDING_SERVICES, which is only set after services are sent)
-  if (this->state_ != espbt::ClientState::INIT && (this->connection_type_ == espbt::ConnectionType::V3_WITH_CACHE ||
-                                                   this->send_service_ == DONE_SENDING_SERVICES)) {
+  if (this->state() != espbt::ClientState::INIT && (this->connection_type_ == espbt::ConnectionType::V3_WITH_CACHE ||
+                                                    this->send_service_ == DONE_SENDING_SERVICES)) {
     this->disable_loop();
   }
 }

esphome/components/cc1101/cc1101.cpp

@@ -152,6 +152,13 @@ void CC1101Component::setup() {
   }
 }
 
+void CC1101Component::call_listeners_(const std::vector<uint8_t> &packet, float freq_offset, float rssi, uint8_t lqi) {
+  for (auto &listener : this->listeners_) {
+    listener->on_packet(packet, freq_offset, rssi, lqi);
+  }
+  this->packet_trigger_->trigger(packet, freq_offset, rssi, lqi);
+}
+
 void CC1101Component::loop() {
   if (this->state_.PKT_FORMAT != static_cast<uint8_t>(PacketFormat::PACKET_FORMAT_FIFO) || this->gdo0_pin_ == nullptr ||
       !this->gdo0_pin_->digital_read()) {
@@ -198,7 +205,7 @@ void CC1101Component::loop() {
   bool crc_ok = (this->state_.LQI & STATUS_CRC_OK_MASK) != 0;
   uint8_t lqi = this->state_.LQI & STATUS_LQI_MASK;
   if (this->state_.CRC_EN == 0 || crc_ok) {
-    this->packet_trigger_->trigger(this->packet_, freq_offset, rssi, lqi);
+    this->call_listeners_(this->packet_, freq_offset, rssi, lqi);
   }
 
   // Return to rx

esphome/components/cc1101/cc1101.h

@@ -11,6 +11,11 @@ namespace esphome::cc1101 {
 
 enum class CC1101Error { NONE = 0, TIMEOUT, PARAMS, CRC_ERROR, FIFO_OVERFLOW, PLL_LOCK };
 
+class CC1101Listener {
+ public:
+  virtual void on_packet(const std::vector<uint8_t> &packet, float freq_offset, float rssi, uint8_t lqi) = 0;
+};
+
 class CC1101Component : public Component,
                         public spi::SPIDevice<spi::BIT_ORDER_MSB_FIRST, spi::CLOCK_POLARITY_LOW,
                                               spi::CLOCK_PHASE_LEADING, spi::DATA_RATE_1MHZ> {
@@ -73,6 +78,7 @@ class CC1101Component : public Component,
 
   // Packet mode operations
   CC1101Error transmit_packet(const std::vector<uint8_t> &packet);
+  void register_listener(CC1101Listener *listener) { this->listeners_.push_back(listener); }
   Trigger<std::vector<uint8_t>, float, float, uint8_t> *get_packet_trigger() const { return this->packet_trigger_; }
 
  protected:
@@ -89,9 +95,11 @@ class CC1101Component : public Component,
   InternalGPIOPin *gdo0_pin_{nullptr};
 
   // Packet handling
+  void call_listeners_(const std::vector<uint8_t> &packet, float freq_offset, float rssi, uint8_t lqi);
   Trigger<std::vector<uint8_t>, float, float, uint8_t> *packet_trigger_{
       new Trigger<std::vector<uint8_t>, float, float, uint8_t>()};
   std::vector<uint8_t> packet_;
+  std::vector<CC1101Listener *> listeners_;
 
   // Low-level Helpers
   uint8_t strobe_(Command cmd);

esphome/components/datetime/date_entity.cpp

@@ -106,9 +106,9 @@ DateCall &DateCall::set_date(uint16_t year, uint8_t month, uint8_t day) {
 
 DateCall &DateCall::set_date(ESPTime time) { return this->set_date(time.year, time.month, time.day_of_month); };
 
-DateCall &DateCall::set_date(const std::string &date) {
+DateCall &DateCall::set_date(const char *date, size_t len) {
   ESPTime val{};
-  if (!ESPTime::strptime(date, val)) {
+  if (!ESPTime::strptime(date, len, val)) {
     ESP_LOGE(TAG, "Could not convert the date string to an ESPTime object");
     return *this;
   }

esphome/components/datetime/date_entity.h

@@ -67,7 +67,9 @@ class DateCall {
   void perform();
   DateCall &set_date(uint16_t year, uint8_t month, uint8_t day);
   DateCall &set_date(ESPTime time);
-  DateCall &set_date(const std::string &date);
+  DateCall &set_date(const char *date, size_t len);
+  DateCall &set_date(const char *date) { return this->set_date(date, strlen(date)); }
+  DateCall &set_date(const std::string &date) { return this->set_date(date.c_str(), date.size()); }
 
   DateCall &set_year(uint16_t year) {
     this->year_ = year;

esphome/components/datetime/datetime_entity.cpp

@@ -163,9 +163,9 @@ DateTimeCall &DateTimeCall::set_datetime(ESPTime datetime) {
                             datetime.second);
 };
 
-DateTimeCall &DateTimeCall::set_datetime(const std::string &datetime) {
+DateTimeCall &DateTimeCall::set_datetime(const char *datetime, size_t len) {
   ESPTime val{};
-  if (!ESPTime::strptime(datetime, val)) {
+  if (!ESPTime::strptime(datetime, len, val)) {
     ESP_LOGE(TAG, "Could not convert the time string to an ESPTime object");
     return *this;
   }

esphome/components/datetime/datetime_entity.h

@@ -71,7 +71,11 @@ class DateTimeCall {
   void perform();
   DateTimeCall &set_datetime(uint16_t year, uint8_t month, uint8_t day, uint8_t hour, uint8_t minute, uint8_t second);
   DateTimeCall &set_datetime(ESPTime datetime);
-  DateTimeCall &set_datetime(const std::string &datetime);
+  DateTimeCall &set_datetime(const char *datetime, size_t len);
+  DateTimeCall &set_datetime(const char *datetime) { return this->set_datetime(datetime, strlen(datetime)); }
+  DateTimeCall &set_datetime(const std::string &datetime) {
+    return this->set_datetime(datetime.c_str(), datetime.size());
+  }
   DateTimeCall &set_datetime(time_t epoch_seconds);
 
   DateTimeCall &set_year(uint16_t year) {

esphome/components/datetime/time_entity.cpp

@@ -74,9 +74,9 @@ TimeCall &TimeCall::set_time(uint8_t hour, uint8_t minute, uint8_t second) {
 
 TimeCall &TimeCall::set_time(ESPTime time) { return this->set_time(time.hour, time.minute, time.second); };
 
-TimeCall &TimeCall::set_time(const std::string &time) {
+TimeCall &TimeCall::set_time(const char *time, size_t len) {
   ESPTime val{};
-  if (!ESPTime::strptime(time, val)) {
+  if (!ESPTime::strptime(time, len, val)) {
     ESP_LOGE(TAG, "Could not convert the time string to an ESPTime object");
     return *this;
   }

esphome/components/datetime/time_entity.h

@@ -69,7 +69,9 @@ class TimeCall {
   void perform();
   TimeCall &set_time(uint8_t hour, uint8_t minute, uint8_t second);
   TimeCall &set_time(ESPTime time);
-  TimeCall &set_time(const std::string &time);
+  TimeCall &set_time(const char *time, size_t len);
+  TimeCall &set_time(const char *time) { return this->set_time(time, strlen(time)); }
+  TimeCall &set_time(const std::string &time) { return this->set_time(time.c_str(), time.size()); }
 
   TimeCall &set_hour(uint8_t hour) {
     this->hour_ = hour;

esphome/components/debug/debug_esp8266.cpp

@@ -3,21 +3,80 @@
 #include "esphome/core/log.h"
 #include <Esp.h>
 
+extern "C" {
+#include <user_interface.h>
+
+// Global reset info struct populated by SDK at boot
+extern struct rst_info resetInfo;
+
+// Core version - either a string pointer or a version number to format as hex
+extern uint32_t core_version;
+extern const char *core_release;
+}
+
 namespace esphome {
 namespace debug {
 
 static const char *const TAG = "debug";
 
+// Get reset reason string from reason code (no heap allocation)
+// Returns LogString* pointing to flash (PROGMEM) on ESP8266
+static const LogString *get_reset_reason_str(uint32_t reason) {
+  switch (reason) {
+    case REASON_DEFAULT_RST:
+      return LOG_STR("Power On");
+    case REASON_WDT_RST:
+      return LOG_STR("Hardware Watchdog");
+    case REASON_EXCEPTION_RST:
+      return LOG_STR("Exception");
+    case REASON_SOFT_WDT_RST:
+      return LOG_STR("Software Watchdog");
+    case REASON_SOFT_RESTART:
+      return LOG_STR("Software/System restart");
+    case REASON_DEEP_SLEEP_AWAKE:
+      return LOG_STR("Deep-Sleep Wake");
+    case REASON_EXT_SYS_RST:
+      return LOG_STR("External System");
+    default:
+      return LOG_STR("Unknown");
+  }
+}
+
+// Size for core version hex buffer
+static constexpr size_t CORE_VERSION_BUFFER_SIZE = 12;
+
+// Get core version string (no heap allocation)
+// Returns either core_release directly or formats core_version as hex into provided buffer
+static const char *get_core_version_str(std::span<char, CORE_VERSION_BUFFER_SIZE> buffer) {
+  if (core_release != nullptr) {
+    return core_release;
+  }
+  snprintf_P(buffer.data(), CORE_VERSION_BUFFER_SIZE, PSTR("%08x"), core_version);
+  return buffer.data();
+}
+
+// Size for reset info buffer
+static constexpr size_t RESET_INFO_BUFFER_SIZE = 200;
+
+// Get detailed reset info string (no heap allocation)
+// For watchdog/exception resets, includes detailed exception info
+static const char *get_reset_info_str(std::span<char, RESET_INFO_BUFFER_SIZE> buffer, uint32_t reason) {
+  if (reason >= REASON_WDT_RST && reason <= REASON_SOFT_WDT_RST) {
+    snprintf_P(buffer.data(), RESET_INFO_BUFFER_SIZE,
+               PSTR("Fatal exception:%d flag:%d (%s) epc1:0x%08x epc2:0x%08x epc3:0x%08x excvaddr:0x%08x depc:0x%08x"),
+               static_cast<int>(resetInfo.exccause), static_cast<int>(reason),
+               LOG_STR_ARG(get_reset_reason_str(reason)), resetInfo.epc1, resetInfo.epc2, resetInfo.epc3,
+               resetInfo.excvaddr, resetInfo.depc);
+    return buffer.data();
+  }
+  return LOG_STR_ARG(get_reset_reason_str(reason));
+}
+
 const char *DebugComponent::get_reset_reason_(std::span<char, RESET_REASON_BUFFER_SIZE> buffer) {
-  char *buf = buffer.data();
-#if !defined(CLANG_TIDY)
-  String reason = ESP.getResetReason();  // NOLINT
-  snprintf_P(buf, RESET_REASON_BUFFER_SIZE, PSTR("%s"), reason.c_str());
-  return buf;
-#else
-  buf[0] = '\0';
-  return buf;
-#endif
+  // Copy from flash to provided buffer
+  strncpy_P(buffer.data(), (PGM_P) get_reset_reason_str(resetInfo.reason), RESET_REASON_BUFFER_SIZE - 1);
+  buffer[RESET_REASON_BUFFER_SIZE - 1] = '\0';
+  return buffer.data();
 }
 
 const char *DebugComponent::get_wakeup_cause_(std::span<char, RESET_REASON_BUFFER_SIZE> buffer) {
@@ -33,37 +92,42 @@ size_t DebugComponent::get_device_info_(std::span<char, DEVICE_INFO_BUFFER_SIZE>
   constexpr size_t size = DEVICE_INFO_BUFFER_SIZE;
   char *buf = buffer.data();
 
-  const char *flash_mode;
+  const LogString *flash_mode;
   switch (ESP.getFlashChipMode()) {  // NOLINT(readability-static-accessed-through-instance)
     case FM_QIO:
-      flash_mode = "QIO";
+      flash_mode = LOG_STR("QIO");
       break;
     case FM_QOUT:
-      flash_mode = "QOUT";
+      flash_mode = LOG_STR("QOUT");
       break;
     case FM_DIO:
-      flash_mode = "DIO";
+      flash_mode = LOG_STR("DIO");
       break;
     case FM_DOUT:
-      flash_mode = "DOUT";
+      flash_mode = LOG_STR("DOUT");
       break;
     default:
-      flash_mode = "UNKNOWN";
+      flash_mode = LOG_STR("UNKNOWN");
   }
-  uint32_t flash_size = ESP.getFlashChipSize() / 1024;       // NOLINT
-  uint32_t flash_speed = ESP.getFlashChipSpeed() / 1000000;  // NOLINT
-  ESP_LOGD(TAG, "Flash Chip: Size=%" PRIu32 "kB Speed=%" PRIu32 "MHz Mode=%s", flash_size, flash_speed, flash_mode);
+  uint32_t flash_size = ESP.getFlashChipSize() / 1024;       // NOLINT(readability-static-accessed-through-instance)
+  uint32_t flash_speed = ESP.getFlashChipSpeed() / 1000000;  // NOLINT(readability-static-accessed-through-instance)
+  ESP_LOGD(TAG, "Flash Chip: Size=%" PRIu32 "kB Speed=%" PRIu32 "MHz Mode=%s", flash_size, flash_speed,
+           LOG_STR_ARG(flash_mode));
   pos = buf_append_printf(buf, size, pos, "|Flash: %" PRIu32 "kB Speed:%" PRIu32 "MHz Mode:%s", flash_size, flash_speed,
-                          flash_mode);
+                          LOG_STR_ARG(flash_mode));
 
-#if !defined(CLANG_TIDY)
   char reason_buffer[RESET_REASON_BUFFER_SIZE];
-  const char *reset_reason = get_reset_reason_(std::span<char, RESET_REASON_BUFFER_SIZE>(reason_buffer));
+  const char *reset_reason = get_reset_reason_(reason_buffer);
+  char core_version_buffer[CORE_VERSION_BUFFER_SIZE];
+  char reset_info_buffer[RESET_INFO_BUFFER_SIZE];
+  // NOLINTBEGIN(readability-static-accessed-through-instance)
   uint32_t chip_id = ESP.getChipId();
   uint8_t boot_version = ESP.getBootVersion();
   uint8_t boot_mode = ESP.getBootMode();
   uint8_t cpu_freq = ESP.getCpuFreqMHz();
   uint32_t flash_chip_id = ESP.getFlashChipId();
+  const char *sdk_version = ESP.getSdkVersion();
+  // NOLINTEND(readability-static-accessed-through-instance)
 
   ESP_LOGD(TAG,
            "Chip ID: 0x%08" PRIX32 "\n"
@@ -74,19 +138,18 @@ size_t DebugComponent::get_device_info_(std::span<char, DEVICE_INFO_BUFFER_SIZE>
            "Flash Chip ID=0x%08" PRIX32 "\n"
            "Reset Reason: %s\n"
            "Reset Info: %s",
-           chip_id, ESP.getSdkVersion(), ESP.getCoreVersion().c_str(), boot_version, boot_mode, cpu_freq, flash_chip_id,
-           reset_reason, ESP.getResetInfo().c_str());
+           chip_id, sdk_version, get_core_version_str(core_version_buffer), boot_version, boot_mode, cpu_freq,
+           flash_chip_id, reset_reason, get_reset_info_str(reset_info_buffer, resetInfo.reason));
 
   pos = buf_append_printf(buf, size, pos, "|Chip: 0x%08" PRIX32, chip_id);
-  pos = buf_append_printf(buf, size, pos, "|SDK: %s", ESP.getSdkVersion());
-  pos = buf_append_printf(buf, size, pos, "|Core: %s", ESP.getCoreVersion().c_str());
+  pos = buf_append_printf(buf, size, pos, "|SDK: %s", sdk_version);
+  pos = buf_append_printf(buf, size, pos, "|Core: %s", get_core_version_str(core_version_buffer));
   pos = buf_append_printf(buf, size, pos, "|Boot: %u", boot_version);
   pos = buf_append_printf(buf, size, pos, "|Mode: %u", boot_mode);
   pos = buf_append_printf(buf, size, pos, "|CPU: %u", cpu_freq);
   pos = buf_append_printf(buf, size, pos, "|Flash: 0x%08" PRIX32, flash_chip_id);
   pos = buf_append_printf(buf, size, pos, "|Reset: %s", reset_reason);
-  pos = buf_append_printf(buf, size, pos, "|%s", ESP.getResetInfo().c_str());
-#endif
+  pos = buf_append_printf(buf, size, pos, "|%s", get_reset_info_str(reset_info_buffer, resetInfo.reason));
 
   return pos;
 }

esphome/components/debug/debug_zephyr.cpp

@@ -132,6 +132,26 @@ void DebugComponent::log_partition_info_() {
   flash_area_foreach(fa_cb, nullptr);
 }
 
+static const char *regout0_to_str(uint32_t value) {
+  switch (value) {
+    case (UICR_REGOUT0_VOUT_DEFAULT):
+      return "1.8V (default)";
+    case (UICR_REGOUT0_VOUT_1V8):
+      return "1.8V";
+    case (UICR_REGOUT0_VOUT_2V1):
+      return "2.1V";
+    case (UICR_REGOUT0_VOUT_2V4):
+      return "2.4V";
+    case (UICR_REGOUT0_VOUT_2V7):
+      return "2.7V";
+    case (UICR_REGOUT0_VOUT_3V0):
+      return "3.0V";
+    case (UICR_REGOUT0_VOUT_3V3):
+      return "3.3V";
+  }
+  return "???V";
+}
+
 size_t DebugComponent::get_device_info_(std::span<char, DEVICE_INFO_BUFFER_SIZE> buffer, size_t pos) {
   constexpr size_t size = DEVICE_INFO_BUFFER_SIZE;
   char *buf = buffer.data();
@@ -145,34 +165,14 @@ size_t DebugComponent::get_device_info_(std::span<char, DEVICE_INFO_BUFFER_SIZE>
   // Regulator stage 0
   if (nrf_power_mainregstatus_get(NRF_POWER) == NRF_POWER_MAINREGSTATUS_HIGH) {
     const char *reg0_type = nrf_power_dcdcen_vddh_get(NRF_POWER) ? "DC/DC" : "LDO";
-    const char *reg0_voltage;
-    switch (NRF_UICR->REGOUT0 & UICR_REGOUT0_VOUT_Msk) {
-      case (UICR_REGOUT0_VOUT_DEFAULT << UICR_REGOUT0_VOUT_Pos):
-        reg0_voltage = "1.8V (default)";
-        break;
-      case (UICR_REGOUT0_VOUT_1V8 << UICR_REGOUT0_VOUT_Pos):
-        reg0_voltage = "1.8V";
-        break;
-      case (UICR_REGOUT0_VOUT_2V1 << UICR_REGOUT0_VOUT_Pos):
-        reg0_voltage = "2.1V";
-        break;
-      case (UICR_REGOUT0_VOUT_2V4 << UICR_REGOUT0_VOUT_Pos):
-        reg0_voltage = "2.4V";
-        break;
-      case (UICR_REGOUT0_VOUT_2V7 << UICR_REGOUT0_VOUT_Pos):
-        reg0_voltage = "2.7V";
-        break;
-      case (UICR_REGOUT0_VOUT_3V0 << UICR_REGOUT0_VOUT_Pos):
-        reg0_voltage = "3.0V";
-        break;
-      case (UICR_REGOUT0_VOUT_3V3 << UICR_REGOUT0_VOUT_Pos):
-        reg0_voltage = "3.3V";
-        break;
-      default:
-        reg0_voltage = "???V";
-    }
+    const char *reg0_voltage = regout0_to_str((NRF_UICR->REGOUT0 & UICR_REGOUT0_VOUT_Msk) >> UICR_REGOUT0_VOUT_Pos);
     ESP_LOGD(TAG, "Regulator stage 0: %s, %s", reg0_type, reg0_voltage);
     pos = buf_append_printf(buf, size, pos, "|Regulator stage 0: %s, %s", reg0_type, reg0_voltage);
+#ifdef USE_NRF52_REG0_VOUT
+    if ((NRF_UICR->REGOUT0 & UICR_REGOUT0_VOUT_Msk) >> UICR_REGOUT0_VOUT_Pos != USE_NRF52_REG0_VOUT) {
+      ESP_LOGE(TAG, "Regulator stage 0: expected %s", regout0_to_str(USE_NRF52_REG0_VOUT));
+    }
+#endif
   } else {
     ESP_LOGD(TAG, "Regulator stage 0: disabled");
     pos = buf_append_printf(buf, size, pos, "|Regulator stage 0: disabled");

esphome/components/epaper_spi/display.py

@@ -190,7 +190,7 @@ async def to_code(config):
     # Rotation is handled by setting the transform
     display_config = {k: v for k, v in config.items() if k != CONF_ROTATION}
     await display.register_display(var, display_config)
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
 
     dc = await cg.gpio_pin_expression(config[CONF_DC_PIN])
     cg.add(var.set_dc_pin(dc))

esphome/components/esp32/__init__.py

@@ -34,6 +34,7 @@ from esphome.const import (
     KEY_CORE,
     KEY_FRAMEWORK_VERSION,
     KEY_NAME,
+    KEY_NATIVE_IDF,
     KEY_TARGET_FRAMEWORK,
     KEY_TARGET_PLATFORM,
     PLATFORM_ESP32,
@@ -53,6 +54,7 @@ from .const import (  # noqa
     KEY_COMPONENTS,
     KEY_ESP32,
     KEY_EXTRA_BUILD_FILES,
+    KEY_FLASH_SIZE,
     KEY_PATH,
     KEY_REF,
     KEY_REPO,
@@ -180,6 +182,12 @@ def set_core_data(config):
             path=[CONF_CPU_FREQUENCY],
         )
 
+    if variant == VARIANT_ESP32P4 and cpu_frequency == "400MHZ":
+        _LOGGER.warning(
+            "400MHz on ESP32-P4 is experimental and may not boot. "
+            "Consider using 360MHz instead. See https://github.com/esphome/esphome/issues/13425"
+        )
+
     CORE.data[KEY_ESP32] = {}
     CORE.data[KEY_CORE][KEY_TARGET_PLATFORM] = PLATFORM_ESP32
     conf = config[CONF_FRAMEWORK]
@@ -199,6 +207,7 @@ def set_core_data(config):
     )
 
     CORE.data[KEY_ESP32][KEY_BOARD] = config[CONF_BOARD]
+    CORE.data[KEY_ESP32][KEY_FLASH_SIZE] = config[CONF_FLASH_SIZE]
     CORE.data[KEY_ESP32][KEY_VARIANT] = variant
     CORE.data[KEY_ESP32][KEY_EXTRA_BUILD_FILES] = {}
 
@@ -339,7 +348,12 @@ def add_extra_build_file(filename: str, path: Path) -> bool:
 def _format_framework_arduino_version(ver: cv.Version) -> str:
     # format the given arduino (https://github.com/espressif/arduino-esp32/releases) version to
     # a PIO pioarduino/framework-arduinoespressif32 value
-    return f"pioarduino/framework-arduinoespressif32@https://github.com/espressif/arduino-esp32/releases/download/{str(ver)}/esp32-{str(ver)}.zip"
+    # 3.3.6+ changed filename from esp32-{ver}.zip to esp32-core-{ver}.tar.xz
+    if ver >= cv.Version(3, 3, 6):
+        filename = f"esp32-core-{ver}.tar.xz"
+    else:
+        filename = f"esp32-{ver}.zip"
+    return f"pioarduino/framework-arduinoespressif32@https://github.com/espressif/arduino-esp32/releases/download/{ver}/{filename}"
 
 
 def _format_framework_espidf_version(ver: cv.Version, release: str) -> str:
@@ -374,11 +388,12 @@ def _is_framework_url(source: str) -> bool:
 # The default/recommended arduino framework version
 #  - https://github.com/espressif/arduino-esp32/releases
 ARDUINO_FRAMEWORK_VERSION_LOOKUP = {
-    "recommended": cv.Version(3, 3, 5),
-    "latest": cv.Version(3, 3, 5),
-    "dev": cv.Version(3, 3, 5),
+    "recommended": cv.Version(3, 3, 6),
+    "latest": cv.Version(3, 3, 6),
+    "dev": cv.Version(3, 3, 6),
 }
 ARDUINO_PLATFORM_VERSION_LOOKUP = {
+    cv.Version(3, 3, 6): cv.Version(55, 3, 36),
     cv.Version(3, 3, 5): cv.Version(55, 3, 35),
     cv.Version(3, 3, 4): cv.Version(55, 3, 31, "2"),
     cv.Version(3, 3, 3): cv.Version(55, 3, 31, "2"),
@@ -396,6 +411,7 @@ ARDUINO_PLATFORM_VERSION_LOOKUP = {
 # These versions correspond to pioarduino/esp-idf releases
 # See: https://github.com/pioarduino/esp-idf/releases
 ARDUINO_IDF_VERSION_LOOKUP = {
+    cv.Version(3, 3, 6): cv.Version(5, 5, 2),
     cv.Version(3, 3, 5): cv.Version(5, 5, 2),
     cv.Version(3, 3, 4): cv.Version(5, 5, 1),
     cv.Version(3, 3, 3): cv.Version(5, 5, 1),
@@ -418,7 +434,7 @@ ESP_IDF_FRAMEWORK_VERSION_LOOKUP = {
     "dev": cv.Version(5, 5, 2),
 }
 ESP_IDF_PLATFORM_VERSION_LOOKUP = {
-    cv.Version(5, 5, 2): cv.Version(55, 3, 35),
+    cv.Version(5, 5, 2): cv.Version(55, 3, 36),
     cv.Version(5, 5, 1): cv.Version(55, 3, 31, "2"),
     cv.Version(5, 5, 0): cv.Version(55, 3, 31, "2"),
     cv.Version(5, 4, 3): cv.Version(55, 3, 32),
@@ -435,9 +451,9 @@ ESP_IDF_PLATFORM_VERSION_LOOKUP = {
 # The platform-espressif32 version
 #  - https://github.com/pioarduino/platform-espressif32/releases
 PLATFORM_VERSION_LOOKUP = {
-    "recommended": cv.Version(55, 3, 35),
-    "latest": cv.Version(55, 3, 35),
-    "dev": cv.Version(55, 3, 35),
+    "recommended": cv.Version(55, 3, 36),
+    "latest": cv.Version(55, 3, 36),
+    "dev": cv.Version(55, 3, 36),
 }
 
 
@@ -962,12 +978,54 @@ async def _add_yaml_idf_components(components: list[ConfigType]):
 
 
 async def to_code(config):
-    cg.add_platformio_option("board", config[CONF_BOARD])
-    cg.add_platformio_option("board_upload.flash_size", config[CONF_FLASH_SIZE])
-    cg.add_platformio_option(
-        "board_upload.maximum_size",
-        int(config[CONF_FLASH_SIZE].removesuffix("MB")) * 1024 * 1024,
-    )
+    framework_ver: cv.Version = CORE.data[KEY_CORE][KEY_FRAMEWORK_VERSION]
+    conf = config[CONF_FRAMEWORK]
+
+    # Check if using native ESP-IDF build (--native-idf)
+    use_platformio = not CORE.data.get(KEY_NATIVE_IDF, False)
+    if use_platformio:
+        # Clear IDF environment variables to avoid conflicts with PlatformIO's ESP-IDF
+        # but keep them when using --native-idf for native ESP-IDF builds
+        for clean_var in ("IDF_PATH", "IDF_TOOLS_PATH"):
+            os.environ.pop(clean_var, None)
+
+        cg.add_platformio_option("lib_ldf_mode", "off")
+        cg.add_platformio_option("lib_compat_mode", "strict")
+        cg.add_platformio_option("platform", conf[CONF_PLATFORM_VERSION])
+        cg.add_platformio_option("board", config[CONF_BOARD])
+        cg.add_platformio_option("board_upload.flash_size", config[CONF_FLASH_SIZE])
+        cg.add_platformio_option(
+            "board_upload.maximum_size",
+            int(config[CONF_FLASH_SIZE].removesuffix("MB")) * 1024 * 1024,
+        )
+
+        if CONF_SOURCE in conf:
+            cg.add_platformio_option("platform_packages", [conf[CONF_SOURCE]])
+
+        add_extra_script(
+            "pre",
+            "pre_build.py",
+            Path(__file__).parent / "pre_build.py.script",
+        )
+
+        add_extra_script(
+            "post",
+            "post_build.py",
+            Path(__file__).parent / "post_build.py.script",
+        )
+
+        # In testing mode, add IRAM fix script to allow linking grouped component tests
+        # Similar to ESP8266's approach but for ESP-IDF
+        if CORE.testing_mode:
+            cg.add_build_flag("-DESPHOME_TESTING_MODE")
+            add_extra_script(
+                "pre",
+                "iram_fix.py",
+                Path(__file__).parent / "iram_fix.py.script",
+            )
+    else:
+        cg.add_build_flag("-Wno-error=format")
+
     cg.set_cpp_standard("gnu++20")
     cg.add_build_flag("-DUSE_ESP32")
     cg.add_build_flag("-Wl,-z,noexecstack")
@@ -977,79 +1035,49 @@ async def to_code(config):
     cg.add_define("ESPHOME_VARIANT", VARIANT_FRIENDLY[variant])
     cg.add_define(ThreadModel.MULTI_ATOMICS)
 
-    cg.add_platformio_option("lib_ldf_mode", "off")
-    cg.add_platformio_option("lib_compat_mode", "strict")
-
-    framework_ver: cv.Version = CORE.data[KEY_CORE][KEY_FRAMEWORK_VERSION]
-
-    conf = config[CONF_FRAMEWORK]
-    cg.add_platformio_option("platform", conf[CONF_PLATFORM_VERSION])
-    if CONF_SOURCE in conf:
-        cg.add_platformio_option("platform_packages", [conf[CONF_SOURCE]])
-
     if conf[CONF_ADVANCED][CONF_IGNORE_EFUSE_CUSTOM_MAC]:
         cg.add_define("USE_ESP32_IGNORE_EFUSE_CUSTOM_MAC")
 
-    for clean_var in ("IDF_PATH", "IDF_TOOLS_PATH"):
-        os.environ.pop(clean_var, None)
-
     # Set the location of the IDF component manager cache
     os.environ["IDF_COMPONENT_CACHE_PATH"] = str(
         CORE.relative_internal_path(".espressif")
     )
 
-    add_extra_script(
-        "pre",
-        "pre_build.py",
-        Path(__file__).parent / "pre_build.py.script",
-    )
-
-    add_extra_script(
-        "post",
-        "post_build.py",
-        Path(__file__).parent / "post_build.py.script",
-    )
-
-    # In testing mode, add IRAM fix script to allow linking grouped component tests
-    # Similar to ESP8266's approach but for ESP-IDF
-    if CORE.testing_mode:
-        cg.add_build_flag("-DESPHOME_TESTING_MODE")
-        add_extra_script(
-            "pre",
-            "iram_fix.py",
-            Path(__file__).parent / "iram_fix.py.script",
-        )
-
     if conf[CONF_TYPE] == FRAMEWORK_ESP_IDF:
-        cg.add_platformio_option("framework", "espidf")
         cg.add_build_flag("-DUSE_ESP_IDF")
         cg.add_build_flag("-DUSE_ESP32_FRAMEWORK_ESP_IDF")
+        if use_platformio:
+            cg.add_platformio_option("framework", "espidf")
     else:
-        cg.add_platformio_option("framework", "arduino, espidf")
         cg.add_build_flag("-DUSE_ARDUINO")
         cg.add_build_flag("-DUSE_ESP32_FRAMEWORK_ARDUINO")
+        if use_platformio:
+            cg.add_platformio_option("framework", "arduino, espidf")
+
+            # Add IDF framework source for Arduino builds to ensure it uses the same version as
+            # the ESP-IDF framework
+            if (idf_ver := ARDUINO_IDF_VERSION_LOOKUP.get(framework_ver)) is not None:
+                cg.add_platformio_option(
+                    "platform_packages",
+                    [_format_framework_espidf_version(idf_ver, None)],
+                )
+
+            # ESP32-S2 Arduino: Disable USB Serial on boot to avoid TinyUSB dependency
+            if get_esp32_variant() == VARIANT_ESP32S2:
+                cg.add_build_unflag("-DARDUINO_USB_CDC_ON_BOOT=1")
+                cg.add_build_unflag("-DARDUINO_USB_CDC_ON_BOOT=0")
+                cg.add_build_flag("-DARDUINO_USB_CDC_ON_BOOT=0")
+
         cg.add_define(
             "USE_ARDUINO_VERSION_CODE",
             cg.RawExpression(
                 f"VERSION_CODE({framework_ver.major}, {framework_ver.minor}, {framework_ver.patch})"
             ),
         )
+
         add_idf_sdkconfig_option("CONFIG_MBEDTLS_PSK_MODES", True)
         add_idf_sdkconfig_option("CONFIG_MBEDTLS_CERTIFICATE_BUNDLE", True)
 
-        # Add IDF framework source for Arduino builds to ensure it uses the same version as
-        # the ESP-IDF framework
-        if (idf_ver := ARDUINO_IDF_VERSION_LOOKUP.get(framework_ver)) is not None:
-            cg.add_platformio_option(
-                "platform_packages", [_format_framework_espidf_version(idf_ver, None)]
-            )
-
-        # ESP32-S2 Arduino: Disable USB Serial on boot to avoid TinyUSB dependency
-        if get_esp32_variant() == VARIANT_ESP32S2:
-            cg.add_build_unflag("-DARDUINO_USB_CDC_ON_BOOT=1")
-            cg.add_build_unflag("-DARDUINO_USB_CDC_ON_BOOT=0")
-            cg.add_build_flag("-DARDUINO_USB_CDC_ON_BOOT=0")
-
     cg.add_build_flag("-Wno-nonnull-compare")
 
     add_idf_sdkconfig_option(f"CONFIG_IDF_TARGET_{variant}", True)
@@ -1196,7 +1224,8 @@ async def to_code(config):
             "CONFIG_VFS_SUPPORT_DIR", not advanced[CONF_DISABLE_VFS_SUPPORT_DIR]
         )
 
-    cg.add_platformio_option("board_build.partitions", "partitions.csv")
+    if use_platformio:
+        cg.add_platformio_option("board_build.partitions", "partitions.csv")
     if CONF_PARTITIONS in config:
         add_extra_build_file(
             "partitions.csv", CORE.relative_config_path(config[CONF_PARTITIONS])
@@ -1361,19 +1390,16 @@ def copy_files():
     _write_idf_component_yml()
 
     if "partitions.csv" not in CORE.data[KEY_ESP32][KEY_EXTRA_BUILD_FILES]:
+        flash_size = CORE.data[KEY_ESP32][KEY_FLASH_SIZE]
         if CORE.using_arduino:
             write_file_if_changed(
                 CORE.relative_build_path("partitions.csv"),
-                get_arduino_partition_csv(
-                    CORE.platformio_options.get("board_upload.flash_size")
-                ),
+                get_arduino_partition_csv(flash_size),
             )
         else:
             write_file_if_changed(
                 CORE.relative_build_path("partitions.csv"),
-                get_idf_partition_csv(
-                    CORE.platformio_options.get("board_upload.flash_size")
-                ),
+                get_idf_partition_csv(flash_size),
             )
     # IDF build scripts look for version string to put in the build.
     # However, if the build path does not have an initialized git repo,

esphome/components/esp32/const.py

@@ -2,6 +2,7 @@ import esphome.codegen as cg
 
 KEY_ESP32 = "esp32"
 KEY_BOARD = "board"
+KEY_FLASH_SIZE = "flash_size"
 KEY_VARIANT = "variant"
 KEY_SDKCONFIG_OPTIONS = "sdkconfig_options"
 KEY_COMPONENTS = "components"

esphome/components/esp32/preferences.cpp

@@ -181,7 +181,8 @@ class ESP32Preferences : public ESPPreferences {
     if (actual_len != to_save.len) {
       return true;
     }
-    auto stored_data = std::make_unique<uint8_t[]>(actual_len);
+    // Most preferences are small, use stack buffer with heap fallback for large ones
+    SmallBufferWithHeapFallback<256> stored_data(actual_len);
     err = nvs_get_blob(nvs_handle, key_str, stored_data.get(), &actual_len);
     if (err != 0) {
       ESP_LOGV(TAG, "nvs_get_blob('%s') failed: %s", key_str, esp_err_to_name(err));

esphome/components/esp32_ble_client/ble_client_base.cpp

@@ -50,7 +50,7 @@ void BLEClientBase::loop() {
     this->set_state(espbt::ClientState::INIT);
     return;
   }
-  if (this->state_ == espbt::ClientState::INIT) {
+  if (this->state() == espbt::ClientState::INIT) {
     auto ret = esp_ble_gattc_app_register(this->app_id);
     if (ret) {
       ESP_LOGE(TAG, "gattc app register failed. app_id=%d code=%d", this->app_id, ret);
@@ -60,7 +60,7 @@ void BLEClientBase::loop() {
   }
   // If idle, we can disable the loop as connect()
   // will enable it again when a connection is needed.
-  else if (this->state_ == espbt::ClientState::IDLE) {
+  else if (this->state() == espbt::ClientState::IDLE) {
     this->disable_loop();
   }
 }
@@ -86,7 +86,7 @@ bool BLEClientBase::parse_device(const espbt::ESPBTDevice &device) {
     return false;
   if (this->address_ == 0 || device.address_uint64() != this->address_)
     return false;
-  if (this->state_ != espbt::ClientState::IDLE)
+  if (this->state() != espbt::ClientState::IDLE)
     return false;
 
   this->log_event_("Found device");
@@ -102,10 +102,10 @@ bool BLEClientBase::parse_device(const espbt::ESPBTDevice &device) {
 
 void BLEClientBase::connect() {
   // Prevent duplicate connection attempts
-  if (this->state_ == espbt::ClientState::CONNECTING || this->state_ == espbt::ClientState::CONNECTED ||
-      this->state_ == espbt::ClientState::ESTABLISHED) {
+  if (this->state() == espbt::ClientState::CONNECTING || this->state() == espbt::ClientState::CONNECTED ||
+      this->state() == espbt::ClientState::ESTABLISHED) {
     ESP_LOGW(TAG, "[%d] [%s] Connection already in progress, state=%s", this->connection_index_, this->address_str_,
-             espbt::client_state_to_string(this->state_));
+             espbt::client_state_to_string(this->state()));
     return;
   }
   ESP_LOGI(TAG, "[%d] [%s] 0x%02x Connecting", this->connection_index_, this->address_str_, this->remote_addr_type_);
@@ -133,12 +133,12 @@ void BLEClientBase::connect() {
 esp_err_t BLEClientBase::pair() { return esp_ble_set_encryption(this->remote_bda_, ESP_BLE_SEC_ENCRYPT); }
 
 void BLEClientBase::disconnect() {
-  if (this->state_ == espbt::ClientState::IDLE || this->state_ == espbt::ClientState::DISCONNECTING) {
+  if (this->state() == espbt::ClientState::IDLE || this->state() == espbt::ClientState::DISCONNECTING) {
     ESP_LOGI(TAG, "[%d] [%s] Disconnect requested, but already %s", this->connection_index_, this->address_str_,
-             espbt::client_state_to_string(this->state_));
+             espbt::client_state_to_string(this->state()));
     return;
   }
-  if (this->state_ == espbt::ClientState::CONNECTING || this->conn_id_ == UNSET_CONN_ID) {
+  if (this->state() == espbt::ClientState::CONNECTING || this->conn_id_ == UNSET_CONN_ID) {
     ESP_LOGD(TAG, "[%d] [%s] Disconnect before connected, disconnect scheduled", this->connection_index_,
              this->address_str_);
     this->want_disconnect_ = true;
@@ -150,7 +150,7 @@ void BLEClientBase::disconnect() {
 void BLEClientBase::unconditional_disconnect() {
   // Disconnect without checking the state.
   ESP_LOGI(TAG, "[%d] [%s] Disconnecting (conn_id: %d).", this->connection_index_, this->address_str_, this->conn_id_);
-  if (this->state_ == espbt::ClientState::DISCONNECTING) {
+  if (this->state() == espbt::ClientState::DISCONNECTING) {
     this->log_error_("Already disconnecting");
     return;
   }
@@ -170,7 +170,7 @@ void BLEClientBase::unconditional_disconnect() {
     this->log_gattc_warning_("esp_ble_gattc_close", err);
   }
 
-  if (this->state_ == espbt::ClientState::DISCOVERED) {
+  if (this->state() == espbt::ClientState::DISCOVERED) {
     this->set_address(0);
     this->set_state(espbt::ClientState::IDLE);
   } else {
@@ -295,18 +295,18 @@ bool BLEClientBase::gattc_event_handler(esp_gattc_cb_event_t event, esp_gatt_if_
       // ESP-IDF's BLE stack may send ESP_GATTC_OPEN_EVT after esp_ble_gattc_open() returns an
       // error, if the error occurred at the BTA/GATT layer. This can result in the event
       // arriving after we've already transitioned to IDLE state.
-      if (this->state_ == espbt::ClientState::IDLE) {
+      if (this->state() == espbt::ClientState::IDLE) {
         ESP_LOGD(TAG, "[%d] [%s] ESP_GATTC_OPEN_EVT in IDLE state (status=%d), ignoring", this->connection_index_,
                  this->address_str_, param->open.status);
         break;
       }
 
-      if (this->state_ != espbt::ClientState::CONNECTING) {
+      if (this->state() != espbt::ClientState::CONNECTING) {
         // This should not happen but lets log it in case it does
         // because it means we have a bad assumption about how the
         // ESP BT stack works.
         ESP_LOGE(TAG, "[%d] [%s] ESP_GATTC_OPEN_EVT in %s state (status=%d)", this->connection_index_,
-                 this->address_str_, espbt::client_state_to_string(this->state_), param->open.status);
+                 this->address_str_, espbt::client_state_to_string(this->state()), param->open.status);
       }
       if (param->open.status != ESP_GATT_OK && param->open.status != ESP_GATT_ALREADY_OPEN) {
         this->log_gattc_warning_("Connection open", param->open.status);
@@ -327,7 +327,7 @@ bool BLEClientBase::gattc_event_handler(esp_gattc_cb_event_t event, esp_gatt_if_
       if (this->connection_type_ == espbt::ConnectionType::V3_WITH_CACHE) {
         // Cached connections already connected with medium parameters, no update needed
         // only set our state, subclients might have more stuff to do yet.
-        this->state_ = espbt::ClientState::ESTABLISHED;
+        this->set_state_internal_(espbt::ClientState::ESTABLISHED);
         break;
       }
       // For V3_WITHOUT_CACHE, we already set fast params before connecting
@@ -356,7 +356,7 @@ bool BLEClientBase::gattc_event_handler(esp_gattc_cb_event_t event, esp_gatt_if_
         return false;
       // Check if we were disconnected while waiting for service discovery
       if (param->disconnect.reason == ESP_GATT_CONN_TERMINATE_PEER_USER &&
-          this->state_ == espbt::ClientState::CONNECTED) {
+          this->state() == espbt::ClientState::CONNECTED) {
         this->log_warning_("Remote closed during discovery");
       } else {
         ESP_LOGD(TAG, "[%d] [%s] ESP_GATTC_DISCONNECT_EVT, reason 0x%02x", this->connection_index_, this->address_str_,
@@ -433,7 +433,7 @@ bool BLEClientBase::gattc_event_handler(esp_gattc_cb_event_t event, esp_gatt_if_
 #endif
       }
       ESP_LOGI(TAG, "[%d] [%s] Service discovery complete", this->connection_index_, this->address_str_);
-      this->state_ = espbt::ClientState::ESTABLISHED;
+      this->set_state_internal_(espbt::ClientState::ESTABLISHED);
       break;
     }
     case ESP_GATTC_READ_DESCR_EVT: {

esphome/components/esp32_ble_client/ble_client_base.h

@@ -44,7 +44,7 @@ class BLEClientBase : public espbt::ESPBTClient, public Component {
   void unconditional_disconnect();
   void release_services();
 
-  bool connected() { return this->state_ == espbt::ClientState::ESTABLISHED; }
+  bool connected() { return this->state() == espbt::ClientState::ESTABLISHED; }
 
   void set_auto_connect(bool auto_connect) { this->auto_connect_ = auto_connect; }
 

esphome/components/esp32_ble_tracker/esp32_ble_tracker.cpp

@@ -105,15 +105,13 @@ void ESP32BLETracker::loop() {
   }
 
   // Check for scan timeout - moved here from scheduler to avoid false reboots
-  // when the loop is blocked
+  // when the loop is blocked. This must run every iteration for safety.
   if (this->scanner_state_ == ScannerState::RUNNING) {
     switch (this->scan_timeout_state_) {
       case ScanTimeoutState::MONITORING: {
-        uint32_t now = App.get_loop_component_start_time();
-        uint32_t timeout_ms = this->scan_duration_ * 2000;
         // Robust time comparison that handles rollover correctly
         // This works because unsigned arithmetic wraps around predictably
-        if ((now - this->scan_start_time_) > timeout_ms) {
+        if ((App.get_loop_component_start_time() - this->scan_start_time_) > this->scan_timeout_ms_) {
           // First time we've seen the timeout exceeded - wait one more loop iteration
           // This ensures all components have had a chance to process pending events
           // This is because esp32_ble may not have run yet and called
@@ -128,13 +126,31 @@ void ESP32BLETracker::loop() {
         ESP_LOGE(TAG, "Scan never terminated, rebooting");
         App.reboot();
         break;
-
       case ScanTimeoutState::INACTIVE:
-        // This case should be unreachable - scanner and timeout states are always synchronized
         break;
     }
   }
 
+  // Fast path: skip expensive client state counting and processing
+  // if no state has changed since last loop iteration.
+  //
+  // How state changes ensure we reach the code below:
+  // - handle_scanner_failure_(): scanner_state_ becomes FAILED via set_scanner_state_(), or
+  //   scan_set_param_failed_ requires scanner_state_==RUNNING which can only be reached via
+  //   set_scanner_state_(RUNNING) in gap_scan_start_complete_() (scan params are set during
+  //   STARTING, not RUNNING, so version is always incremented before this condition is true)
+  // - start_scan_(): scanner_state_ becomes IDLE via set_scanner_state_() in cleanup_scan_state_()
+  // - try_promote_discovered_clients_(): client enters DISCOVERED via set_state(), or
+  //   connecting client finishes (state change), or scanner reaches RUNNING/IDLE
+  //
+  // All conditions that affect the logic below are tied to state changes that increment
+  // state_version_, so the fast path is safe.
+  if (this->state_version_ == this->last_processed_version_) {
+    return;
+  }
+  this->last_processed_version_ = this->state_version_;
+
+  // State changed - do full processing
   ClientStateCounts counts = this->count_client_states_();
   if (counts != this->client_state_counts_) {
     this->client_state_counts_ = counts;
@@ -142,6 +158,7 @@ void ESP32BLETracker::loop() {
              this->client_state_counts_.discovered, this->client_state_counts_.disconnecting);
   }
 
+  // Scanner failure: reached when set_scanner_state_(FAILED) or scan_set_param_failed_ set
   if (this->scanner_state_ == ScannerState::FAILED ||
       (this->scan_set_param_failed_ && this->scanner_state_ == ScannerState::RUNNING)) {
     this->handle_scanner_failure_();
@@ -160,6 +177,8 @@ void ESP32BLETracker::loop() {
 
   */
 
+  // Start scan: reached when scanner_state_ becomes IDLE (via set_scanner_state_()) and
+  // all clients are idle (their state changes increment version when they finish)
   if (this->scanner_state_ == ScannerState::IDLE && !counts.connecting && !counts.disconnecting && !counts.discovered) {
 #ifdef USE_ESP32_BLE_SOFTWARE_COEXISTENCE
     this->update_coex_preference_(false);
@@ -168,8 +187,9 @@ void ESP32BLETracker::loop() {
       this->start_scan_(false);  // first = false
     }
   }
-  // If there is a discovered client and no connecting
-  // clients, then promote the discovered client to ready to connect.
+  // Promote discovered clients: reached when a client's state becomes DISCOVERED (via set_state()),
+  // or when a blocking condition clears (connecting client finishes, scanner reaches RUNNING/IDLE).
+  // All these trigger state_version_ increment, so we'll process and check promotion eligibility.
   // We check both RUNNING and IDLE states because:
   // - RUNNING: gap_scan_event_handler initiates stop_scan_() but promotion can happen immediately
   // - IDLE: Scanner has already stopped (naturally or by gap_scan_event_handler)
@@ -236,6 +256,7 @@ void ESP32BLETracker::start_scan_(bool first) {
   // Start timeout monitoring in loop() instead of using scheduler
   // This prevents false reboots when the loop is blocked
   this->scan_start_time_ = App.get_loop_component_start_time();
+  this->scan_timeout_ms_ = this->scan_duration_ * 2000;
   this->scan_timeout_state_ = ScanTimeoutState::MONITORING;
 
   esp_err_t err = esp_ble_gap_set_scan_params(&this->scan_params_);
@@ -253,6 +274,10 @@ void ESP32BLETracker::start_scan_(bool first) {
 void ESP32BLETracker::register_client(ESPBTClient *client) {
 #ifdef ESPHOME_ESP32_BLE_TRACKER_CLIENT_COUNT
   client->app_id = ++this->app_id_;
+  // Give client a pointer to our state_version_ so it can notify us of state changes.
+  // This enables loop() fast-path optimization - we skip expensive work when no state changed.
+  // Safe because ESP32BLETracker (singleton) outlives all registered clients.
+  client->set_tracker_state_version(&this->state_version_);
   this->clients_.push_back(client);
   this->recalculate_advertisement_parser_types();
 #endif
@@ -382,6 +407,7 @@ void ESP32BLETracker::gattc_event_handler(esp_gattc_cb_event_t event, esp_gatt_i
 
 void ESP32BLETracker::set_scanner_state_(ScannerState state) {
   this->scanner_state_ = state;
+  this->state_version_++;
   for (auto *listener : this->scanner_state_listeners_) {
     listener->on_scanner_state(state);
   }

esphome/components/esp32_ble_tracker/esp32_ble_tracker.h

@@ -216,6 +216,19 @@ enum class ConnectionType : uint8_t {
   V3_WITHOUT_CACHE
 };
 
+/// Base class for BLE GATT clients that connect to remote devices.
+///
+/// State Change Tracking Design:
+/// -----------------------------
+/// ESP32BLETracker::loop() needs to know when client states change to avoid
+/// expensive polling. Rather than checking all clients every iteration (~7000/min),
+/// we use a version counter owned by ESP32BLETracker that clients increment on
+/// state changes. The tracker compares versions to skip work when nothing changed.
+///
+/// Ownership: ESP32BLETracker owns state_version_. Clients hold a non-owning
+/// pointer (tracker_state_version_) set during register_client(). Clients
+/// increment the counter through this pointer when their state changes.
+/// The pointer may be null if the client is not registered with a tracker.
 class ESPBTClient : public ESPBTDeviceListener {
  public:
   virtual bool gattc_event_handler(esp_gattc_cb_event_t event, esp_gatt_if_t gattc_if,
@@ -225,26 +238,49 @@ class ESPBTClient : public ESPBTDeviceListener {
   virtual void disconnect() = 0;
   bool disconnect_pending() const { return this->want_disconnect_; }
   void cancel_pending_disconnect() { this->want_disconnect_ = false; }
+
+  /// Set the client state with IDLE handling (clears want_disconnect_).
+  /// Notifies the tracker of state change for loop optimization.
   virtual void set_state(ClientState st) {
-    this->state_ = st;
+    this->set_state_internal_(st);
     if (st == ClientState::IDLE) {
       this->want_disconnect_ = false;
     }
   }
-  ClientState state() const { return state_; }
+  ClientState state() const { return this->state_; }
+
+  /// Called by ESP32BLETracker::register_client() to enable state change notifications.
+  /// The pointer must remain valid for the lifetime of the client (guaranteed since
+  /// ESP32BLETracker is a singleton that outlives all clients).
+  void set_tracker_state_version(uint8_t *version) { this->tracker_state_version_ = version; }
 
   // Memory optimized layout
   uint8_t app_id;  // App IDs are small integers assigned sequentially
 
  protected:
-  // Group 1: 1-byte types
-  ClientState state_{ClientState::INIT};
+  /// Set state without IDLE handling - use for direct state transitions.
+  /// Increments the tracker's state version counter to signal that loop()
+  /// should do full processing on the next iteration.
+  void set_state_internal_(ClientState st) {
+    this->state_ = st;
+    // Notify tracker that state changed (tracker_state_version_ is owned by ESP32BLETracker)
+    if (this->tracker_state_version_ != nullptr) {
+      (*this->tracker_state_version_)++;
+    }
+  }
+
   // want_disconnect_ is set to true when a disconnect is requested
   // while the client is connecting. This is used to disconnect the
   // client as soon as we get the connection id (conn_id_) from the
   // ESP_GATTC_OPEN_EVT event.
   bool want_disconnect_{false};
-  // 2 bytes used, 2 bytes padding
+
+ private:
+  ClientState state_{ClientState::INIT};
+  /// Non-owning pointer to ESP32BLETracker::state_version_. When this client's
+  /// state changes, we increment the tracker's counter to signal that loop()
+  /// should perform full processing. Null if client not registered with tracker.
+  uint8_t *tracker_state_version_{nullptr};
 };
 
 class ESP32BLETracker : public Component,
@@ -380,6 +416,16 @@ class ESP32BLETracker : public Component,
   // Group 4: 1-byte types (enums, uint8_t, bool)
   uint8_t app_id_{0};
   uint8_t scan_start_fail_count_{0};
+  /// Version counter for loop() fast-path optimization. Incremented when:
+  /// - Scanner state changes (via set_scanner_state_())
+  /// - Any registered client's state changes (clients hold pointer to this counter)
+  /// Owned by this class; clients receive non-owning pointer via register_client().
+  /// When loop() sees state_version_ == last_processed_version_, it skips expensive
+  /// client state counting and takes the fast path (just timeout check + return).
+  uint8_t state_version_{0};
+  /// Last state_version_ value when loop() did full processing. Compared against
+  /// state_version_ to detect if any state changed since last iteration.
+  uint8_t last_processed_version_{0};
   ScannerState scanner_state_{ScannerState::IDLE};
   bool scan_continuous_;
   bool scan_active_;
@@ -396,6 +442,8 @@ class ESP32BLETracker : public Component,
     EXCEEDED_WAIT,  // Timeout exceeded, waiting one loop before reboot
   };
   uint32_t scan_start_time_{0};
+  /// Precomputed timeout value: scan_duration_ * 2000
+  uint32_t scan_timeout_ms_{0};
   ScanTimeoutState scan_timeout_state_{ScanTimeoutState::INACTIVE};
 };
 

esphome/components/esp32_hosted/update/esp32_hosted_update.cpp

@@ -11,6 +11,7 @@
 #include <esp_ota_ops.h>
 
 #ifdef USE_ESP32_HOSTED_HTTP_UPDATE
+#include "esphome/components/http_request/http_request.h"
 #include "esphome/components/json/json_util.h"
 #include "esphome/components/network/util.h"
 #endif
@@ -184,15 +185,23 @@ bool Esp32HostedUpdate::fetch_manifest_() {
   }
 
   // Read manifest JSON into string (manifest is small, ~1KB max)
+  // NOTE: HttpContainer::read() has non-BSD socket semantics - see http_request.h
+  // Use http_read_loop_result() helper instead of checking return values directly
   std::string json_str;
   json_str.reserve(container->content_length);
   uint8_t buf[256];
+  uint32_t last_data_time = millis();
+  const uint32_t read_timeout = this->http_request_parent_->get_timeout();
   while (container->get_bytes_read() < container->content_length) {
-    int read = container->read(buf, sizeof(buf));
-    if (read > 0) {
-      json_str.append(reinterpret_cast<char *>(buf), read);
-    }
+    int read_or_error = container->read(buf, sizeof(buf));
+    App.feed_wdt();
     yield();
+    auto result = http_request::http_read_loop_result(read_or_error, last_data_time, read_timeout);
+    if (result == http_request::HttpReadLoopResult::RETRY)
+      continue;
+    if (result != http_request::HttpReadLoopResult::DATA)
+      break;  // ERROR or TIMEOUT
+    json_str.append(reinterpret_cast<char *>(buf), read_or_error);
   }
   container->end();
 
@@ -297,32 +306,38 @@ bool Esp32HostedUpdate::stream_firmware_to_coprocessor_() {
   }
 
   // Stream firmware to coprocessor while computing SHA256
+  // NOTE: HttpContainer::read() has non-BSD socket semantics - see http_request.h
+  // Use http_read_loop_result() helper instead of checking return values directly
   sha256::SHA256 hasher;
   hasher.init();
 
   uint8_t buffer[CHUNK_SIZE];
+  uint32_t last_data_time = millis();
+  const uint32_t read_timeout = this->http_request_parent_->get_timeout();
   while (container->get_bytes_read() < total_size) {
-    int read = container->read(buffer, sizeof(buffer));
+    int read_or_error = container->read(buffer, sizeof(buffer));
 
     // Feed watchdog and give other tasks a chance to run
     App.feed_wdt();
     yield();
 
-    // Exit loop if no data available (stream closed or end of data)
-    if (read <= 0) {
-      if (read < 0) {
-        ESP_LOGE(TAG, "Stream closed with error");
-        esp_hosted_slave_ota_end();  // NOLINT
-        container->end();
-        this->status_set_error(LOG_STR("Download failed"));
-        return false;
+    auto result = http_request::http_read_loop_result(read_or_error, last_data_time, read_timeout);
+    if (result == http_request::HttpReadLoopResult::RETRY)
+      continue;
+    if (result != http_request::HttpReadLoopResult::DATA) {
+      if (result == http_request::HttpReadLoopResult::TIMEOUT) {
+        ESP_LOGE(TAG, "Timeout reading firmware data");
+      } else {
+        ESP_LOGE(TAG, "Error reading firmware data: %d", read_or_error);
       }
-      // read == 0: no more data available, exit loop
-      break;
+      esp_hosted_slave_ota_end();  // NOLINT
+      container->end();
+      this->status_set_error(LOG_STR("Download failed"));
+      return false;
     }
 
-    hasher.add(buffer, read);
-    err = esp_hosted_slave_ota_write(buffer, read);  // NOLINT
+    hasher.add(buffer, read_or_error);
+    err = esp_hosted_slave_ota_write(buffer, read_or_error);  // NOLINT
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to write OTA data: %s", esp_err_to_name(err));
       esp_hosted_slave_ota_end();  // NOLINT

esphome/components/esp8266/preferences.cpp

@@ -12,7 +12,6 @@ extern "C" {
 #include "preferences.h"
 
 #include <cstring>
-#include <memory>
 
 namespace esphome::esp8266 {
 
@@ -143,16 +142,8 @@ class ESP8266PreferenceBackend : public ESPPreferenceBackend {
       return false;
 
     const size_t buffer_size = static_cast<size_t>(this->length_words) + 1;
-    uint32_t stack_buffer[PREF_BUFFER_WORDS];
-    std::unique_ptr<uint32_t[]> heap_buffer;
-    uint32_t *buffer;
-
-    if (buffer_size <= PREF_BUFFER_WORDS) {
-      buffer = stack_buffer;
-    } else {
-      heap_buffer = make_unique<uint32_t[]>(buffer_size);
-      buffer = heap_buffer.get();
-    }
+    SmallBufferWithHeapFallback<PREF_BUFFER_WORDS, uint32_t> buffer_alloc(buffer_size);
+    uint32_t *buffer = buffer_alloc.get();
     memset(buffer, 0, buffer_size * sizeof(uint32_t));
 
     memcpy(buffer, data, len);
@@ -167,16 +158,8 @@ class ESP8266PreferenceBackend : public ESPPreferenceBackend {
       return false;
 
     const size_t buffer_size = static_cast<size_t>(this->length_words) + 1;
-    uint32_t stack_buffer[PREF_BUFFER_WORDS];
-    std::unique_ptr<uint32_t[]> heap_buffer;
-    uint32_t *buffer;
-
-    if (buffer_size <= PREF_BUFFER_WORDS) {
-      buffer = stack_buffer;
-    } else {
-      heap_buffer = make_unique<uint32_t[]>(buffer_size);
-      buffer = heap_buffer.get();
-    }
+    SmallBufferWithHeapFallback<PREF_BUFFER_WORDS, uint32_t> buffer_alloc(buffer_size);
+    uint32_t *buffer = buffer_alloc.get();
 
     bool ret = this->in_flash ? load_from_flash(this->offset, buffer, buffer_size)
                               : load_from_rtc(this->offset, buffer, buffer_size);

esphome/components/hc8/sensor.py

@@ -6,6 +6,7 @@ from esphome.const import (
     CONF_BASELINE,
     CONF_CO2,
     CONF_ID,
+    CONF_WARMUP_TIME,
     DEVICE_CLASS_CARBON_DIOXIDE,
     ICON_MOLECULE_CO2,
     STATE_CLASS_MEASUREMENT,
@@ -14,8 +15,6 @@ from esphome.const import (
 
 DEPENDENCIES = ["uart"]
 
-CONF_WARMUP_TIME = "warmup_time"
-
 hc8_ns = cg.esphome_ns.namespace("hc8")
 HC8Component = hc8_ns.class_("HC8Component", cg.PollingComponent, uart.UARTDevice)
 HC8CalibrateAction = hc8_ns.class_("HC8CalibrateAction", automation.Action)

esphome/components/heatpumpir/climate.py

@@ -107,7 +107,7 @@ CONFIG_SCHEMA = cv.All(
             cv.Required(CONF_MAX_TEMPERATURE): cv.temperature,
         }
     ),
-    cv.only_with_arduino,
+    cv.Any(cv.only_with_arduino, cv.only_on_esp32),
 )
 
 
@@ -126,6 +126,6 @@ async def to_code(config):
     cg.add(var.set_max_temperature(config[CONF_MAX_TEMPERATURE]))
     cg.add(var.set_min_temperature(config[CONF_MIN_TEMPERATURE]))
 
-    cg.add_library("tonia/HeatpumpIR", "1.0.37")
+    cg.add_library("tonia/HeatpumpIR", "1.0.40")
     if CORE.is_libretiny or CORE.is_esp32:
         CORE.add_platformio_option("lib_ignore", ["IRremoteESP8266"])

esphome/components/heatpumpir/heatpumpir.cpp

@@ -1,6 +1,6 @@
 #include "heatpumpir.h"
 
-#ifdef USE_ARDUINO
+#if defined(USE_ARDUINO) || defined(USE_ESP32)
 
 #include <map>
 #include "ir_sender_esphome.h"

esphome/components/heatpumpir/heatpumpir.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#ifdef USE_ARDUINO
+#if defined(USE_ARDUINO) || defined(USE_ESP32)
 
 #include "esphome/components/climate_ir/climate_ir.h"
 

esphome/components/heatpumpir/ir_sender_esphome.cpp

@@ -1,6 +1,6 @@
 #include "ir_sender_esphome.h"
 
-#ifdef USE_ARDUINO
+#if defined(USE_ARDUINO) || defined(USE_ESP32)
 
 namespace esphome {
 namespace heatpumpir {

esphome/components/heatpumpir/ir_sender_esphome.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#ifdef USE_ARDUINO
+#if defined(USE_ARDUINO) || defined(USE_ESP32)
 
 #include "esphome/components/remote_base/remote_base.h"
 #include <IRSender.h>  // arduino-heatpump library

esphome/components/http_request/__init__.py

@@ -157,6 +157,7 @@ async def to_code(config):
     if CORE.is_esp32:
         cg.add(var.set_buffer_size_rx(config[CONF_BUFFER_SIZE_RX]))
         cg.add(var.set_buffer_size_tx(config[CONF_BUFFER_SIZE_TX]))
+        cg.add(var.set_verify_ssl(config[CONF_VERIFY_SSL]))
 
         if config.get(CONF_VERIFY_SSL):
             esp32.add_idf_sdkconfig_option("CONFIG_MBEDTLS_CERTIFICATE_BUNDLE", True)

esphome/components/http_request/http_request.h

@@ -79,6 +79,81 @@ inline bool is_redirect(int const status) {
  */
 inline bool is_success(int const status) { return status >= HTTP_STATUS_OK && status < HTTP_STATUS_MULTIPLE_CHOICES; }
 
+/*
+ * HTTP Container Read Semantics
+ * =============================
+ *
+ * IMPORTANT: These semantics differ from standard BSD sockets!
+ *
+ * BSD socket read() returns:
+ *   > 0: bytes read
+ *   == 0: connection closed (EOF)
+ *   < 0: error (check errno)
+ *
+ * HttpContainer::read() returns:
+ *   > 0: bytes read successfully
+ *   == 0: no data available yet OR all content read
+ *         (caller should check bytes_read vs content_length)
+ *   < 0: error or connection closed (caller should EXIT)
+ *        HTTP_ERROR_CONNECTION_CLOSED (-1) = connection closed prematurely
+ *        other negative values = platform-specific errors
+ *
+ * Platform behaviors:
+ *   - ESP-IDF: blocking reads, 0 only returned when all content read
+ *   - Arduino: non-blocking, 0 means "no data yet" or "all content read"
+ *
+ * Use the helper functions below instead of checking return values directly:
+ *   - http_read_loop_result(): for manual loops with per-chunk processing
+ *   - http_read_fully(): for simple "read N bytes into buffer" operations
+ */
+
+/// Error code returned by HttpContainer::read() when connection closed prematurely
+/// NOTE: Unlike BSD sockets where 0 means EOF, here 0 means "no data yet, retry"
+static constexpr int HTTP_ERROR_CONNECTION_CLOSED = -1;
+
+/// Status of a read operation
+enum class HttpReadStatus : uint8_t {
+  OK,       ///< Read completed successfully
+  ERROR,    ///< Read error occurred
+  TIMEOUT,  ///< Timeout waiting for data
+};
+
+/// Result of an HTTP read operation
+struct HttpReadResult {
+  HttpReadStatus status;  ///< Status of the read operation
+  int error_code;         ///< Error code from read() on failure, 0 on success
+};
+
+/// Result of processing a non-blocking read with timeout (for manual loops)
+enum class HttpReadLoopResult : uint8_t {
+  DATA,     ///< Data was read, process it
+  RETRY,    ///< No data yet, already delayed, caller should continue loop
+  ERROR,    ///< Read error, caller should exit loop
+  TIMEOUT,  ///< Timeout waiting for data, caller should exit loop
+};
+
+/// Process a read result with timeout tracking and delay handling
+/// @param bytes_read_or_error Return value from read() - positive for bytes read, negative for error
+/// @param last_data_time Time of last successful read, updated when data received
+/// @param timeout_ms Maximum time to wait for data
+/// @return DATA if data received, RETRY if should continue loop, ERROR/TIMEOUT if should exit
+inline HttpReadLoopResult http_read_loop_result(int bytes_read_or_error, uint32_t &last_data_time,
+                                                uint32_t timeout_ms) {
+  if (bytes_read_or_error > 0) {
+    last_data_time = millis();
+    return HttpReadLoopResult::DATA;
+  }
+  if (bytes_read_or_error < 0) {
+    return HttpReadLoopResult::ERROR;
+  }
+  // bytes_read_or_error == 0: no data available yet
+  if (millis() - last_data_time >= timeout_ms) {
+    return HttpReadLoopResult::TIMEOUT;
+  }
+  delay(1);  // Small delay to prevent tight spinning
+  return HttpReadLoopResult::RETRY;
+}
+
 class HttpRequestComponent;
 
 class HttpContainer : public Parented<HttpRequestComponent> {
@@ -88,6 +163,33 @@ class HttpContainer : public Parented<HttpRequestComponent> {
   int status_code;
   uint32_t duration_ms;
 
+  /**
+   * @brief Read data from the HTTP response body.
+   *
+   * WARNING: These semantics differ from BSD sockets!
+   * BSD sockets: 0 = EOF (connection closed)
+   * This method: 0 = no data yet OR all content read, negative = error/closed
+   *
+   * @param buf Buffer to read data into
+   * @param max_len Maximum number of bytes to read
+   * @return
+   *   - > 0: Number of bytes read successfully
+   *   - 0: No data available yet OR all content read
+   *        (check get_bytes_read() >= content_length to distinguish)
+   *   - HTTP_ERROR_CONNECTION_CLOSED (-1): Connection closed prematurely
+   *   - < -1: Other error (platform-specific error code)
+   *
+   * Platform notes:
+   *   - ESP-IDF: blocking read, 0 only when all content read
+   *   - Arduino: non-blocking, 0 can mean "no data yet" or "all content read"
+   *
+   * Use get_bytes_read() and content_length to track progress.
+   * When get_bytes_read() >= content_length, all data has been received.
+   *
+   * IMPORTANT: Do not use raw return values directly. Use these helpers:
+   *   - http_read_loop_result(): for loops with per-chunk processing
+   *   - http_read_fully(): for simple "read N bytes" operations
+   */
   virtual int read(uint8_t *buf, size_t max_len) = 0;
   virtual void end() = 0;
 
@@ -110,6 +212,38 @@ class HttpContainer : public Parented<HttpRequestComponent> {
   std::map<std::string, std::list<std::string>> response_headers_{};
 };
 
+/// Read data from HTTP container into buffer with timeout handling
+/// Handles feed_wdt, yield, and timeout checking internally
+/// @param container The HTTP container to read from
+/// @param buffer Buffer to read into
+/// @param total_size Total bytes to read
+/// @param chunk_size Maximum bytes per read call
+/// @param timeout_ms Read timeout in milliseconds
+/// @return HttpReadResult with status and error_code on failure
+inline HttpReadResult http_read_fully(HttpContainer *container, uint8_t *buffer, size_t total_size, size_t chunk_size,
+                                      uint32_t timeout_ms) {
+  size_t read_index = 0;
+  uint32_t last_data_time = millis();
+
+  while (read_index < total_size) {
+    int read_bytes_or_error = container->read(buffer + read_index, std::min(chunk_size, total_size - read_index));
+
+    App.feed_wdt();
+    yield();
+
+    auto result = http_read_loop_result(read_bytes_or_error, last_data_time, timeout_ms);
+    if (result == HttpReadLoopResult::RETRY)
+      continue;
+    if (result == HttpReadLoopResult::ERROR)
+      return {HttpReadStatus::ERROR, read_bytes_or_error};
+    if (result == HttpReadLoopResult::TIMEOUT)
+      return {HttpReadStatus::TIMEOUT, 0};
+
+    read_index += read_bytes_or_error;
+  }
+  return {HttpReadStatus::OK, 0};
+}
+
 class HttpRequestResponseTrigger : public Trigger<std::shared_ptr<HttpContainer>, std::string &> {
  public:
   void process(const std::shared_ptr<HttpContainer> &container, std::string &response_body) {
@@ -124,6 +258,7 @@ class HttpRequestComponent : public Component {
 
   void set_useragent(const char *useragent) { this->useragent_ = useragent; }
   void set_timeout(uint32_t timeout) { this->timeout_ = timeout; }
+  uint32_t get_timeout() const { return this->timeout_; }
   void set_watchdog_timeout(uint32_t watchdog_timeout) { this->watchdog_timeout_ = watchdog_timeout; }
   uint32_t get_watchdog_timeout() const { return this->watchdog_timeout_; }
   void set_follow_redirects(bool follow_redirects) { this->follow_redirects_ = follow_redirects; }
@@ -249,15 +384,21 @@ template<typename... Ts> class HttpRequestSendAction : public Action<Ts...> {
       RAMAllocator<uint8_t> allocator;
       uint8_t *buf = allocator.allocate(max_length);
       if (buf != nullptr) {
+        // NOTE: HttpContainer::read() has non-BSD socket semantics - see top of this file
+        // Use http_read_loop_result() helper instead of checking return values directly
         size_t read_index = 0;
+        uint32_t last_data_time = millis();
+        const uint32_t read_timeout = this->parent_->get_timeout();
         while (container->get_bytes_read() < max_length) {
-          int read = container->read(buf + read_index, std::min<size_t>(max_length - read_index, 512));
-          if (read <= 0) {
-            break;
-          }
+          int read_or_error = container->read(buf + read_index, std::min<size_t>(max_length - read_index, 512));
           App.feed_wdt();
           yield();
-          read_index += read;
+          auto result = http_read_loop_result(read_or_error, last_data_time, read_timeout);
+          if (result == HttpReadLoopResult::RETRY)
+            continue;
+          if (result != HttpReadLoopResult::DATA)
+            break;  // ERROR or TIMEOUT
+          read_index += read_or_error;
         }
         response_body.reserve(read_index);
         response_body.assign((char *) buf, read_index);

esphome/components/http_request/http_request_arduino.cpp

@@ -139,6 +139,23 @@ std::shared_ptr<HttpContainer> HttpRequestArduino::perform(const std::string &ur
   return container;
 }
 
+// Arduino HTTP read implementation
+//
+// WARNING: Return values differ from BSD sockets! See http_request.h for full documentation.
+//
+// Arduino's WiFiClient is inherently non-blocking - available() returns 0 when
+// no data is ready. We use connected() to distinguish "no data yet" from
+// "connection closed".
+//
+// WiFiClient behavior:
+//   available() > 0: data ready to read
+//   available() == 0 && connected(): no data yet, still connected
+//   available() == 0 && !connected(): connection closed
+//
+// We normalize to HttpContainer::read() contract (NOT BSD socket semantics!):
+//   > 0: bytes read
+//   0: no data yet, retry            <-- NOTE: 0 means retry, NOT EOF!
+//   < 0: error/connection closed     <-- connection closed returns -1, not 0
 int HttpContainerArduino::read(uint8_t *buf, size_t max_len) {
   const uint32_t start = millis();
   watchdog::WatchdogManager wdm(this->parent_->get_watchdog_timeout());
@@ -146,7 +163,7 @@ int HttpContainerArduino::read(uint8_t *buf, size_t max_len) {
   WiFiClient *stream_ptr = this->client_.getStreamPtr();
   if (stream_ptr == nullptr) {
     ESP_LOGE(TAG, "Stream pointer vanished!");
-    return -1;
+    return HTTP_ERROR_CONNECTION_CLOSED;
   }
 
   int available_data = stream_ptr->available();
@@ -154,7 +171,15 @@ int HttpContainerArduino::read(uint8_t *buf, size_t max_len) {
 
   if (bufsize == 0) {
     this->duration_ms += (millis() - start);
-    return 0;
+    // Check if we've read all expected content
+    if (this->bytes_read_ >= this->content_length) {
+      return 0;  // All content read successfully
+    }
+    // No data available - check if connection is still open
+    if (!stream_ptr->connected()) {
+      return HTTP_ERROR_CONNECTION_CLOSED;  // Connection closed prematurely
+    }
+    return 0;  // No data yet, caller should retry
   }
 
   App.feed_wdt();

esphome/components/http_request/http_request_idf.cpp

@@ -89,7 +89,7 @@ std::shared_ptr<HttpContainer> HttpRequestIDF::perform(const std::string &url, c
   config.max_redirection_count = this->redirect_limit_;
   config.auth_type = HTTP_AUTH_TYPE_BASIC;
 #if CONFIG_MBEDTLS_CERTIFICATE_BUNDLE
-  if (secure) {
+  if (secure && this->verify_ssl_) {
     config.crt_bundle_attach = esp_crt_bundle_attach;
   }
 #endif
@@ -209,26 +209,57 @@ std::shared_ptr<HttpContainer> HttpRequestIDF::perform(const std::string &url, c
   return container;
 }
 
+// ESP-IDF HTTP read implementation (blocking mode)
+//
+// WARNING: Return values differ from BSD sockets! See http_request.h for full documentation.
+//
+// esp_http_client_read() in blocking mode returns:
+//   > 0: bytes read
+//   0: connection closed (end of stream)
+//   < 0: error
+//
+// We normalize to HttpContainer::read() contract:
+//   > 0: bytes read
+//   0: no data yet / all content read (caller should check bytes_read vs content_length)
+//   < 0: error/connection closed
 int HttpContainerIDF::read(uint8_t *buf, size_t max_len) {
   const uint32_t start = millis();
   watchdog::WatchdogManager wdm(this->parent_->get_watchdog_timeout());
 
-  this->feed_wdt();
-  int read_len = esp_http_client_read(this->client_, (char *) buf, max_len);
-  this->feed_wdt();
-  if (read_len > 0) {
-    this->bytes_read_ += read_len;
+  // Check if we've already read all expected content
+  if (this->bytes_read_ >= this->content_length) {
+    return 0;  // All content read successfully
   }
+
+  this->feed_wdt();
+  int read_len_or_error = esp_http_client_read(this->client_, (char *) buf, max_len);
+  this->feed_wdt();
+
   this->duration_ms += (millis() - start);
 
-  return read_len;
+  if (read_len_or_error > 0) {
+    this->bytes_read_ += read_len_or_error;
+    return read_len_or_error;
+  }
+
+  // Connection closed by server before all content received
+  if (read_len_or_error == 0) {
+    return HTTP_ERROR_CONNECTION_CLOSED;
+  }
+
+  // Negative value - error, return the actual error code for debugging
+  return read_len_or_error;
 }
 
 void HttpContainerIDF::end() {
+  if (this->client_ == nullptr) {
+    return;  // Already cleaned up
+  }
   watchdog::WatchdogManager wdm(this->parent_->get_watchdog_timeout());
 
   esp_http_client_close(this->client_);
   esp_http_client_cleanup(this->client_);
+  this->client_ = nullptr;
 }
 
 void HttpContainerIDF::feed_wdt() {

esphome/components/http_request/http_request_idf.h

@@ -34,6 +34,7 @@ class HttpRequestIDF : public HttpRequestComponent {
 
   void set_buffer_size_rx(uint16_t buffer_size_rx) { this->buffer_size_rx_ = buffer_size_rx; }
   void set_buffer_size_tx(uint16_t buffer_size_tx) { this->buffer_size_tx_ = buffer_size_tx; }
+  void set_verify_ssl(bool verify_ssl) { this->verify_ssl_ = verify_ssl; }
 
  protected:
   std::shared_ptr<HttpContainer> perform(const std::string &url, const std::string &method, const std::string &body,
@@ -42,6 +43,7 @@ class HttpRequestIDF : public HttpRequestComponent {
   // if zero ESP-IDF will use DEFAULT_HTTP_BUF_SIZE
   uint16_t buffer_size_rx_{};
   uint16_t buffer_size_tx_{};
+  bool verify_ssl_{true};
 
   /// @brief Monitors the http client events to gather response headers
   static esp_err_t http_event_handler(esp_http_client_event_t *evt);

esphome/components/http_request/ota/ota_http_request.cpp

@@ -115,39 +115,47 @@ uint8_t OtaHttpRequestComponent::do_ota_() {
     return error_code;
   }
 
+  // NOTE: HttpContainer::read() has non-BSD socket semantics - see http_request.h
+  // Use http_read_loop_result() helper instead of checking return values directly
+  uint32_t last_data_time = millis();
+  const uint32_t read_timeout = this->parent_->get_timeout();
+
   while (container->get_bytes_read() < container->content_length) {
-    // read a maximum of chunk_size bytes into buf. (real read size returned)
-    int bufsize = container->read(buf, OtaHttpRequestComponent::HTTP_RECV_BUFFER);
-    ESP_LOGVV(TAG, "bytes_read_ = %u, body_length_ = %u, bufsize = %i", container->get_bytes_read(),
-              container->content_length, bufsize);
+    // read a maximum of chunk_size bytes into buf. (real read size returned, or negative error code)
+    int bufsize_or_error = container->read(buf, OtaHttpRequestComponent::HTTP_RECV_BUFFER);
+    ESP_LOGVV(TAG, "bytes_read_ = %u, body_length_ = %u, bufsize_or_error = %i", container->get_bytes_read(),
+              container->content_length, bufsize_or_error);
 
     // feed watchdog and give other tasks a chance to run
     App.feed_wdt();
     yield();
 
-    // Exit loop if no data available (stream closed or end of data)
-    if (bufsize <= 0) {
-      if (bufsize < 0) {
-        ESP_LOGE(TAG, "Stream closed with error");
-        this->cleanup_(std::move(backend), container);
-        return OTA_CONNECTION_ERROR;
+    auto result = http_read_loop_result(bufsize_or_error, last_data_time, read_timeout);
+    if (result == HttpReadLoopResult::RETRY)
+      continue;
+    if (result != HttpReadLoopResult::DATA) {
+      if (result == HttpReadLoopResult::TIMEOUT) {
+        ESP_LOGE(TAG, "Timeout reading data");
+      } else {
+        ESP_LOGE(TAG, "Error reading data: %d", bufsize_or_error);
       }
-      // bufsize == 0: no more data available, exit loop
-      break;
+      this->cleanup_(std::move(backend), container);
+      return OTA_CONNECTION_ERROR;
     }
 
-    if (bufsize <= OtaHttpRequestComponent::HTTP_RECV_BUFFER) {
+    // At this point bufsize_or_error > 0, so it's a valid size
+    if (bufsize_or_error <= OtaHttpRequestComponent::HTTP_RECV_BUFFER) {
       // add read bytes to MD5
-      md5_receive.add(buf, bufsize);
+      md5_receive.add(buf, bufsize_or_error);
 
       // write bytes to OTA backend
       this->update_started_ = true;
-      error_code = backend->write(buf, bufsize);
+      error_code = backend->write(buf, bufsize_or_error);
       if (error_code != ota::OTA_RESPONSE_OK) {
         // error code explanation available at
         // https://github.com/esphome/esphome/blob/dev/esphome/components/ota/ota_backend.h
         ESP_LOGE(TAG, "Error code (%02X) writing binary data to flash at offset %d and size %d", error_code,
-                 container->get_bytes_read() - bufsize, container->content_length);
+                 container->get_bytes_read() - bufsize_or_error, container->content_length);
         this->cleanup_(std::move(backend), container);
         return error_code;
       }
@@ -244,19 +252,19 @@ bool OtaHttpRequestComponent::http_get_md5_() {
   }
 
   this->md5_expected_.resize(MD5_SIZE);
-  int read_len = 0;
-  while (container->get_bytes_read() < MD5_SIZE) {
-    read_len = container->read((uint8_t *) this->md5_expected_.data(), MD5_SIZE);
-    if (read_len <= 0) {
-      break;
-    }
-    App.feed_wdt();
-    yield();
-  }
+  auto result = http_read_fully(container.get(), (uint8_t *) this->md5_expected_.data(), MD5_SIZE, MD5_SIZE,
+                                this->parent_->get_timeout());
   container->end();
 
-  ESP_LOGV(TAG, "Read len: %u, MD5 expected: %u", read_len, MD5_SIZE);
-  return read_len == MD5_SIZE;
+  if (result.status != HttpReadStatus::OK) {
+    if (result.status == HttpReadStatus::TIMEOUT) {
+      ESP_LOGE(TAG, "Timeout reading MD5");
+    } else {
+      ESP_LOGE(TAG, "Error reading MD5: %d", result.error_code);
+    }
+    return false;
+  }
+  return true;
 }
 
 bool OtaHttpRequestComponent::validate_url_(const std::string &url) {

esphome/components/http_request/update/http_request_update.cpp

@@ -11,7 +11,12 @@ namespace http_request {
 
 // The update function runs in a task only on ESP32s.
 #ifdef USE_ESP32
-#define UPDATE_RETURN vTaskDelete(nullptr)  // Delete the current update task
+// vTaskDelete doesn't return, but clang-tidy doesn't know that
+#define UPDATE_RETURN \
+  do { \
+    vTaskDelete(nullptr); \
+    __builtin_unreachable(); \
+  } while (0)
 #else
 #define UPDATE_RETURN return
 #endif
@@ -70,19 +75,21 @@ void HttpRequestUpdate::update_task(void *params) {
     UPDATE_RETURN;
   }
 
-  size_t read_index = 0;
-  while (container->get_bytes_read() < container->content_length) {
-    int read_bytes = container->read(data + read_index, MAX_READ_SIZE);
-
-    yield();
-
-    if (read_bytes <= 0) {
-      // Network error or connection closed - break to avoid infinite loop
-      break;
+  auto read_result = http_read_fully(container.get(), data, container->content_length, MAX_READ_SIZE,
+                                     this_update->request_parent_->get_timeout());
+  if (read_result.status != HttpReadStatus::OK) {
+    if (read_result.status == HttpReadStatus::TIMEOUT) {
+      ESP_LOGE(TAG, "Timeout reading manifest");
+    } else {
+      ESP_LOGE(TAG, "Error reading manifest: %d", read_result.error_code);
     }
-
-    read_index += read_bytes;
+    // Defer to main loop to avoid race condition on component_state_ read-modify-write
+    this_update->defer([this_update]() { this_update->status_set_error(LOG_STR("Failed to read manifest")); });
+    allocator.deallocate(data, container->content_length);
+    container->end();
+    UPDATE_RETURN;
   }
+  size_t read_index = container->get_bytes_read();
 
   bool valid = false;
   {  // Ensures the response string falls out of scope and deallocates before the task ends

esphome/components/ili9xxx/display.py

@@ -223,7 +223,7 @@ async def to_code(config):
     var = cg.Pvariable(config[CONF_ID], rhs)
 
     await display.register_display(var, config)
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
     dc = await cg.gpio_pin_expression(config[CONF_DC_PIN])
     cg.add(var.set_dc_pin(dc))
     if init_sequences := config.get(CONF_INIT_SEQUENCE):

esphome/components/json/__init__.py

@@ -1,6 +1,6 @@
 import esphome.codegen as cg
 import esphome.config_validation as cv
-from esphome.core import CoroPriority, coroutine_with_priority
+from esphome.core import CORE, CoroPriority, coroutine_with_priority
 
 CODEOWNERS = ["@esphome/core"]
 json_ns = cg.esphome_ns.namespace("json")
@@ -12,6 +12,11 @@ CONFIG_SCHEMA = cv.All(
 
 @coroutine_with_priority(CoroPriority.BUS)
 async def to_code(config):
-    cg.add_library("bblanchon/ArduinoJson", "7.4.2")
+    if CORE.is_esp32:
+        from esphome.components.esp32 import add_idf_component
+
+        add_idf_component(name="bblanchon/arduinojson", ref="7.4.2")
+    else:
+        cg.add_library("bblanchon/ArduinoJson", "7.4.2")
     cg.add_define("USE_JSON")
     cg.add_global(json_ns.using)

esphome/components/libretiny/__init__.py

@@ -382,4 +382,11 @@ async def component_to_code(config):
             "custom_options.sys_config#h", _BK7231N_SYS_CONFIG_OPTIONS
         )
 
+    # Disable LWIP statistics to save RAM - not needed in production
+    # Must explicitly disable all sub-stats to avoid redefinition warnings
+    cg.add_platformio_option(
+        "custom_options.lwip",
+        ["LWIP_STATS=0", "MEM_STATS=0", "MEMP_STATS=0"],
+    )
+
     await cg.register_component(var, config)

esphome/components/libretiny/preferences.cpp

@@ -166,8 +166,8 @@ class LibreTinyPreferences : public ESPPreferences {
       return true;
     }
 
-    // Allocate buffer on heap to avoid stack allocation for large data
-    auto stored_data = std::make_unique<uint8_t[]>(kv.value_len);
+    // Most preferences are small, use stack buffer with heap fallback for large ones
+    SmallBufferWithHeapFallback<256> stored_data(kv.value_len);
     fdb_blob_make(&this->blob, stored_data.get(), kv.value_len);
     size_t actual_len = fdb_kv_get_blob(db, key_str, &this->blob);
     if (actual_len != kv.value_len) {

esphome/components/logger/logger.cpp

@@ -1,8 +1,5 @@
 #include "logger.h"
 #include <cinttypes>
-#ifdef USE_ESPHOME_TASK_LOG_BUFFER
-#include <memory>  // For unique_ptr
-#endif
 
 #include "esphome/core/application.h"
 #include "esphome/core/hal.h"
@@ -199,7 +196,8 @@ inline uint8_t Logger::level_for(const char *tag) {
 
 Logger::Logger(uint32_t baud_rate, size_t tx_buffer_size) : baud_rate_(baud_rate), tx_buffer_size_(tx_buffer_size) {
   // add 1 to buffer size for null terminator
-  this->tx_buffer_ = new char[this->tx_buffer_size_ + 1];  // NOLINT
+  // NOLINTNEXTLINE(cppcoreguidelines-owning-memory) - allocated once, never freed
+  this->tx_buffer_ = new char[this->tx_buffer_size_ + 1];
 #if defined(USE_ESP32) || defined(USE_LIBRETINY)
   this->main_task_ = xTaskGetCurrentTaskHandle();
 #elif defined(USE_ZEPHYR)
@@ -212,11 +210,14 @@ Logger::Logger(uint32_t baud_rate, size_t tx_buffer_size) : baud_rate_(baud_rate
 void Logger::init_log_buffer(size_t total_buffer_size) {
 #ifdef USE_HOST
   // Host uses slot count instead of byte size
-  this->log_buffer_ = esphome::make_unique<logger::TaskLogBufferHost>(total_buffer_size);
+  // NOLINTNEXTLINE(cppcoreguidelines-owning-memory) - allocated once, never freed
+  this->log_buffer_ = new logger::TaskLogBufferHost(total_buffer_size);
 #elif defined(USE_ESP32)
-  this->log_buffer_ = esphome::make_unique<logger::TaskLogBuffer>(total_buffer_size);
+  // NOLINTNEXTLINE(cppcoreguidelines-owning-memory) - allocated once, never freed
+  this->log_buffer_ = new logger::TaskLogBuffer(total_buffer_size);
 #elif defined(USE_LIBRETINY)
-  this->log_buffer_ = esphome::make_unique<logger::TaskLogBufferLibreTiny>(total_buffer_size);
+  // NOLINTNEXTLINE(cppcoreguidelines-owning-memory) - allocated once, never freed
+  this->log_buffer_ = new logger::TaskLogBufferLibreTiny(total_buffer_size);
 #endif
 
 #if defined(USE_ESP32) || defined(USE_LIBRETINY)

esphome/components/logger/logger.h

@@ -412,11 +412,11 @@ class Logger : public Component {
 #endif
 #ifdef USE_ESPHOME_TASK_LOG_BUFFER
 #ifdef USE_HOST
-  std::unique_ptr<logger::TaskLogBufferHost> log_buffer_;  // Will be initialized with init_log_buffer
+  logger::TaskLogBufferHost *log_buffer_{nullptr};  // Allocated once, never freed
 #elif defined(USE_ESP32)
-  std::unique_ptr<logger::TaskLogBuffer> log_buffer_;  // Will be initialized with init_log_buffer
+  logger::TaskLogBuffer *log_buffer_{nullptr};  // Allocated once, never freed
 #elif defined(USE_LIBRETINY)
-  std::unique_ptr<logger::TaskLogBufferLibreTiny> log_buffer_;  // Will be initialized with init_log_buffer
+  logger::TaskLogBufferLibreTiny *log_buffer_{nullptr};  // Allocated once, never freed
 #endif
 #endif
 

esphome/components/lvgl/widgets/dropdown.py

@@ -1,3 +1,4 @@
+from esphome import codegen as cg
 import esphome.config_validation as cv
 from esphome.const import CONF_OPTIONS
 
@@ -24,6 +25,34 @@ from .label import CONF_LABEL
 CONF_DROPDOWN = "dropdown"
 CONF_DROPDOWN_LIST = "dropdown_list"
 
+# Example valid dropdown symbol (left arrow) for error messages
+EXAMPLE_DROPDOWN_SYMBOL = "\U00002190"  # ←
+
+
+def dropdown_symbol_validator(value):
+    """
+    Validate that the dropdown symbol is a single Unicode character
+    with a codepoint of 0x100 (256) or greater.
+    This is required because LVGL uses codepoints below 0x100 for internal symbols.
+    """
+    value = cv.string(value)
+    # len(value) counts Unicode code points, not grapheme clusters or bytes
+    if len(value) != 1:
+        raise cv.Invalid(
+            f"Dropdown symbol must be a single character, got '{value}' with length {len(value)}"
+        )
+    codepoint = ord(value)
+    if codepoint < 0x100:
+        # Format the example symbol as a Unicode escape for the error message
+        example_escape = f"\\U{ord(EXAMPLE_DROPDOWN_SYMBOL):08X}"
+        raise cv.Invalid(
+            f"Dropdown symbol must have a Unicode codepoint of 0x100 (256) or greater. "
+            f"'{value}' has codepoint {codepoint} (0x{codepoint:X}). "
+            f"Use a character like '{example_escape}' ({EXAMPLE_DROPDOWN_SYMBOL}) or other Unicode symbols with codepoint >= 0x100."
+        )
+    return value
+
+
 lv_dropdown_t = LvSelect("LvDropdownType", parents=(LvCompound,))
 
 lv_dropdown_list_t = LvType("lv_dropdown_list_t")
@@ -33,7 +62,7 @@ dropdown_list_spec = WidgetType(
 
 DROPDOWN_BASE_SCHEMA = cv.Schema(
     {
-        cv.Optional(CONF_SYMBOL): lv_text,
+        cv.Optional(CONF_SYMBOL): dropdown_symbol_validator,
         cv.Exclusive(CONF_SELECTED_INDEX, CONF_SELECTED_TEXT): lv_int,
         cv.Exclusive(CONF_SELECTED_TEXT, CONF_SELECTED_TEXT): lv_text,
         cv.Optional(CONF_DROPDOWN_LIST): part_schema(dropdown_list_spec.parts),
@@ -70,7 +99,7 @@ class DropdownType(WidgetType):
         if options := config.get(CONF_OPTIONS):
             lv_add(w.var.set_options(options))
         if symbol := config.get(CONF_SYMBOL):
-            lv.dropdown_set_symbol(w.var.obj, await lv_text.process(symbol))
+            lv.dropdown_set_symbol(w.var.obj, cg.safe_exp(symbol))
         if (selected := config.get(CONF_SELECTED_INDEX)) is not None:
             value = await lv_int.process(selected)
             lv_add(w.var.set_selected_index(value, literal("LV_ANIM_OFF")))

esphome/components/max7219/display.py

@@ -29,7 +29,7 @@ CONFIG_SCHEMA = (
 
 async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
     await display.register_display(var, config)
 
     cg.add(var.set_num_chips(config[CONF_NUM_CHIPS]))

esphome/components/max7219digit/display.py

@@ -86,7 +86,7 @@ CONFIG_SCHEMA = (
 
 async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
     await display.register_display(var, config)
 
     cg.add(var.set_num_chips(config[CONF_NUM_CHIPS]))

esphome/components/mdns/mdns_esp32.cpp

@@ -24,13 +24,14 @@ static void register_esp32(MDNSComponent *comp, StaticVector<MDNSService, MDNS_S
   mdns_instance_name_set(hostname);
 
   for (const auto &service : services) {
-    auto txt_records = std::make_unique<mdns_txt_item_t[]>(service.txt_records.size());
+    // Stack buffer for up to 16 txt records, heap fallback for more
+    SmallBufferWithHeapFallback<16, mdns_txt_item_t> txt_records(service.txt_records.size());
     for (size_t i = 0; i < service.txt_records.size(); i++) {
       const auto &record = service.txt_records[i];
       // key and value are either compile-time string literals in flash or pointers to dynamic_txt_values_
       // Both remain valid for the lifetime of this function, and ESP-IDF makes internal copies
-      txt_records[i].key = MDNS_STR_ARG(record.key);
-      txt_records[i].value = MDNS_STR_ARG(record.value);
+      txt_records.get()[i].key = MDNS_STR_ARG(record.key);
+      txt_records.get()[i].value = MDNS_STR_ARG(record.value);
     }
     uint16_t port = const_cast<TemplatableValue<uint16_t> &>(service.port).value();
     err = mdns_service_add(nullptr, MDNS_STR_ARG(service.service_type), MDNS_STR_ARG(service.proto), port,

esphome/components/mhz19/sensor.py

@@ -7,6 +7,7 @@ from esphome.const import (
     CONF_CO2,
     CONF_ID,
     CONF_TEMPERATURE,
+    CONF_WARMUP_TIME,
     DEVICE_CLASS_CARBON_DIOXIDE,
     DEVICE_CLASS_TEMPERATURE,
     ICON_MOLECULE_CO2,
@@ -18,7 +19,6 @@ from esphome.const import (
 DEPENDENCIES = ["uart"]
 
 CONF_AUTOMATIC_BASELINE_CALIBRATION = "automatic_baseline_calibration"
-CONF_WARMUP_TIME = "warmup_time"
 CONF_DETECTION_RANGE = "detection_range"
 
 mhz19_ns = cg.esphome_ns.namespace("mhz19")

esphome/components/mipi_rgb/display.py

@@ -260,7 +260,7 @@ async def to_code(config):
         cg.add(var.set_enable_pins(enable))
 
     if CONF_SPI_ID in config:
-        await spi.register_spi_device(var, config)
+        await spi.register_spi_device(var, config, write_only=True)
         sequence, madctl = model.get_sequence(config)
         cg.add(var.set_init_sequence(sequence))
         cg.add(var.set_madctl(madctl))

esphome/components/mipi_spi/display.py

@@ -443,6 +443,4 @@ async def to_code(config):
         )
         cg.add(var.set_writer(lambda_))
     await display.register_display(var, config)
-    await spi.register_spi_device(var, config)
-    # Displays are write-only, set the SPI device to write-only as well
-    cg.add(var.set_write_only(True))
+    await spi.register_spi_device(var, config, write_only=True)

esphome/components/mqtt/custom_mqtt_device.cpp

@@ -18,7 +18,7 @@ bool CustomMQTTDevice::publish(const std::string &topic, float value, int8_t num
 }
 bool CustomMQTTDevice::publish(const std::string &topic, int value) {
   char buffer[24];
-  int len = snprintf(buffer, sizeof(buffer), "%d", value);
+  size_t len = buf_append_printf(buffer, sizeof(buffer), 0, "%d", value);
   return global_mqtt_client->publish(topic, buffer, len);
 }
 bool CustomMQTTDevice::publish_json(const std::string &topic, const json::json_build_t &f, uint8_t qos, bool retain) {

esphome/components/mqtt/mqtt_alarm_control_panel.cpp

@@ -43,7 +43,7 @@ void MQTTAlarmControlPanelComponent::setup() {
 
 void MQTTAlarmControlPanelComponent::dump_config() {
   ESP_LOGCONFIG(TAG, "MQTT alarm_control_panel '%s':", this->alarm_control_panel_->get_name().c_str());
-  LOG_MQTT_COMPONENT(true, true)
+  LOG_MQTT_COMPONENT(true, true);
   ESP_LOGCONFIG(TAG,
                 "  Supported Features: %" PRIu32 "\n"
                 "  Requires Code to Disarm: %s\n"

esphome/components/mqtt/mqtt_binary_sensor.cpp

@@ -19,7 +19,7 @@ void MQTTBinarySensorComponent::setup() {
 
 void MQTTBinarySensorComponent::dump_config() {
   ESP_LOGCONFIG(TAG, "MQTT Binary Sensor '%s':", this->binary_sensor_->get_name().c_str());
-  LOG_MQTT_COMPONENT(true, false)
+  LOG_MQTT_COMPONENT(true, false);
 }
 MQTTBinarySensorComponent::MQTTBinarySensorComponent(binary_sensor::BinarySensor *binary_sensor)
     : binary_sensor_(binary_sensor) {

esphome/components/mqtt/mqtt_client.cpp

@@ -98,7 +98,17 @@ void MQTTClientComponent::send_device_info_() {
         uint8_t index = 0;
         for (auto &ip : network::get_ip_addresses()) {
           if (ip.is_set()) {
-            root["ip" + (index == 0 ? "" : esphome::to_string(index))] = ip.str();
+            char key[8];  // "ip" + up to 3 digits + null
+            char ip_buf[network::IP_ADDRESS_BUFFER_SIZE];
+            if (index == 0) {
+              key[0] = 'i';
+              key[1] = 'p';
+              key[2] = '\0';
+            } else {
+              buf_append_printf(key, sizeof(key), 0, "ip%u", index);
+            }
+            ip.str_to(ip_buf);
+            root[key] = ip_buf;
             index++;
           }
         }

esphome/components/mqtt/mqtt_component.cpp

@@ -27,20 +27,23 @@ inline char *append_char(char *p, char c) {
 // Max lengths for stack-based topic building.
 // These limits are enforced at Python config validation time in mqtt/__init__.py
 // using cv.Length() validators for topic_prefix and discovery_prefix.
-// MQTT_COMPONENT_TYPE_MAX_LEN and MQTT_SUFFIX_MAX_LEN are defined in mqtt_component.h.
+// MQTT_COMPONENT_TYPE_MAX_LEN, MQTT_SUFFIX_MAX_LEN, and MQTT_DEFAULT_TOPIC_MAX_LEN are in mqtt_component.h.
 // ESPHOME_DEVICE_NAME_MAX_LEN and OBJECT_ID_MAX_LEN are defined in entity_base.h.
 // This ensures the stack buffers below are always large enough.
-static constexpr size_t TOPIC_PREFIX_MAX_LEN = 64;      // Validated in Python: cv.Length(max=64)
 static constexpr size_t DISCOVERY_PREFIX_MAX_LEN = 64;  // Validated in Python: cv.Length(max=64)
-
-// Stack buffer sizes - safe because all inputs are length-validated at config time
-// Format: prefix + "/" + type + "/" + object_id + "/" + suffix + null
-static constexpr size_t DEFAULT_TOPIC_MAX_LEN =
-    TOPIC_PREFIX_MAX_LEN + 1 + MQTT_COMPONENT_TYPE_MAX_LEN + 1 + OBJECT_ID_MAX_LEN + 1 + MQTT_SUFFIX_MAX_LEN + 1;
 // Format: prefix + "/" + type + "/" + name + "/" + object_id + "/config" + null
 static constexpr size_t DISCOVERY_TOPIC_MAX_LEN = DISCOVERY_PREFIX_MAX_LEN + 1 + MQTT_COMPONENT_TYPE_MAX_LEN + 1 +
                                                   ESPHOME_DEVICE_NAME_MAX_LEN + 1 + OBJECT_ID_MAX_LEN + 7 + 1;
 
+// Function implementation of LOG_MQTT_COMPONENT macro to reduce code size
+void log_mqtt_component(const char *tag, MQTTComponent *obj, bool state_topic, bool command_topic) {
+  char buf[MQTT_DEFAULT_TOPIC_MAX_LEN];
+  if (state_topic)
+    ESP_LOGCONFIG(tag, "  State Topic: '%s'", obj->get_state_topic_to_(buf).c_str());
+  if (command_topic)
+    ESP_LOGCONFIG(tag, "  Command Topic: '%s'", obj->get_command_topic_to_(buf).c_str());
+}
+
 void MQTTComponent::set_qos(uint8_t qos) { this->qos_ = qos; }
 
 void MQTTComponent::set_subscribe_qos(uint8_t qos) { this->subscribe_qos_ = qos; }
@@ -69,19 +72,18 @@ std::string MQTTComponent::get_discovery_topic_(const MQTTDiscoveryInfo &discove
   return std::string(buf, p - buf);
 }
 
-std::string MQTTComponent::get_default_topic_for_(const std::string &suffix) const {
+StringRef MQTTComponent::get_default_topic_for_to_(std::span<char, MQTT_DEFAULT_TOPIC_MAX_LEN> buf, const char *suffix,
+                                                   size_t suffix_len) const {
   const std::string &topic_prefix = global_mqtt_client->get_topic_prefix();
   if (topic_prefix.empty()) {
-    // If the topic_prefix is null, the default topic should be null
-    return "";
+    return StringRef();  // Empty topic_prefix means no default topic
   }
 
   const char *comp_type = this->component_type();
   char object_id_buf[OBJECT_ID_MAX_LEN];
   StringRef object_id = this->get_default_object_id_to_(object_id_buf);
 
-  char buf[DEFAULT_TOPIC_MAX_LEN];
-  char *p = buf;
+  char *p = buf.data();
 
   p = append_str(p, topic_prefix.data(), topic_prefix.size());
   p = append_char(p, '/');
@@ -89,21 +91,44 @@ std::string MQTTComponent::get_default_topic_for_(const std::string &suffix) con
   p = append_char(p, '/');
   p = append_str(p, object_id.c_str(), object_id.size());
   p = append_char(p, '/');
-  p = append_str(p, suffix.data(), suffix.size());
+  p = append_str(p, suffix, suffix_len);
+  *p = '\0';
 
-  return std::string(buf, p - buf);
+  return StringRef(buf.data(), p - buf.data());
+}
+
+std::string MQTTComponent::get_default_topic_for_(const std::string &suffix) const {
+  char buf[MQTT_DEFAULT_TOPIC_MAX_LEN];
+  StringRef ref = this->get_default_topic_for_to_(buf, suffix.data(), suffix.size());
+  return std::string(ref.c_str(), ref.size());
+}
+
+StringRef MQTTComponent::get_state_topic_to_(std::span<char, MQTT_DEFAULT_TOPIC_MAX_LEN> buf) const {
+  if (this->custom_state_topic_.has_value()) {
+    // Returns ref to existing data for static/value, uses buf only for lambda case
+    return this->custom_state_topic_.ref_or_copy_to(buf.data(), buf.size());
+  }
+  return this->get_default_topic_for_to_(buf, "state", 5);
+}
+
+StringRef MQTTComponent::get_command_topic_to_(std::span<char, MQTT_DEFAULT_TOPIC_MAX_LEN> buf) const {
+  if (this->custom_command_topic_.has_value()) {
+    // Returns ref to existing data for static/value, uses buf only for lambda case
+    return this->custom_command_topic_.ref_or_copy_to(buf.data(), buf.size());
+  }
+  return this->get_default_topic_for_to_(buf, "command", 7);
 }
 
 std::string MQTTComponent::get_state_topic_() const {
-  if (this->custom_state_topic_.has_value())
-    return this->custom_state_topic_.value();
-  return this->get_default_topic_for_("state");
+  char buf[MQTT_DEFAULT_TOPIC_MAX_LEN];
+  StringRef ref = this->get_state_topic_to_(buf);
+  return std::string(ref.c_str(), ref.size());
 }
 
 std::string MQTTComponent::get_command_topic_() const {
-  if (this->custom_command_topic_.has_value())
-    return this->custom_command_topic_.value();
-  return this->get_default_topic_for_("command");
+  char buf[MQTT_DEFAULT_TOPIC_MAX_LEN];
+  StringRef ref = this->get_command_topic_to_(buf);
+  return std::string(ref.c_str(), ref.size());
 }
 
 bool MQTTComponent::publish(const std::string &topic, const std::string &payload) {
@@ -168,10 +193,14 @@ bool MQTTComponent::send_discovery_() {
             break;
         }
 
-        if (config.state_topic)
-          root[MQTT_STATE_TOPIC] = this->get_state_topic_();
-        if (config.command_topic)
-          root[MQTT_COMMAND_TOPIC] = this->get_command_topic_();
+        if (config.state_topic) {
+          char state_topic_buf[MQTT_DEFAULT_TOPIC_MAX_LEN];
+          root[MQTT_STATE_TOPIC] = this->get_state_topic_to_(state_topic_buf);
+        }
+        if (config.command_topic) {
+          char command_topic_buf[MQTT_DEFAULT_TOPIC_MAX_LEN];
+          root[MQTT_COMMAND_TOPIC] = this->get_command_topic_to_(command_topic_buf);
+        }
         if (this->command_retain_)
           root[MQTT_COMMAND_RETAIN] = true;
 
@@ -190,27 +219,37 @@ bool MQTTComponent::send_discovery_() {
         StringRef object_id = this->get_default_object_id_to_(object_id_buf);
         if (discovery_info.unique_id_generator == MQTT_MAC_ADDRESS_UNIQUE_ID_GENERATOR) {
           char friendly_name_hash[9];
-          snprintf(friendly_name_hash, sizeof(friendly_name_hash), "%08" PRIx32, fnv1_hash(this->friendly_name_()));
+          buf_append_printf(friendly_name_hash, sizeof(friendly_name_hash), 0, "%08" PRIx32,
+                            fnv1_hash(this->friendly_name_()));
           // Format: mac-component_type-hash (e.g. "aabbccddeeff-sensor-12345678")
           // MAC (12) + "-" (1) + domain (max 20) + "-" (1) + hash (8) + null (1) = 43
           char unique_id[MAC_ADDRESS_BUFFER_SIZE + ESPHOME_DOMAIN_MAX_LEN + 11];
           char mac_buf[MAC_ADDRESS_BUFFER_SIZE];
           get_mac_address_into_buffer(mac_buf);
-          snprintf(unique_id, sizeof(unique_id), "%s-%s-%s", mac_buf, this->component_type(), friendly_name_hash);
+          buf_append_printf(unique_id, sizeof(unique_id), 0, "%s-%s-%s", mac_buf, this->component_type(),
+                            friendly_name_hash);
           root[MQTT_UNIQUE_ID] = unique_id;
         } else {
           // default to almost-unique ID. It's a hack but the only way to get that
           // gorgeous device registry view.
-          root[MQTT_UNIQUE_ID] = "ESP" + std::string(this->component_type()) + object_id.c_str();
+          // "ESP" (3) + component_type (max 20) + object_id (max 128) + null
+          char unique_id_buf[3 + MQTT_COMPONENT_TYPE_MAX_LEN + OBJECT_ID_MAX_LEN + 1];
+          buf_append_printf(unique_id_buf, sizeof(unique_id_buf), 0, "ESP%s%s", this->component_type(),
+                            object_id.c_str());
+          root[MQTT_UNIQUE_ID] = unique_id_buf;
         }
 
         const std::string &node_name = App.get_name();
-        if (discovery_info.object_id_generator == MQTT_DEVICE_NAME_OBJECT_ID_GENERATOR)
-          root[MQTT_OBJECT_ID] = node_name + "_" + object_id.c_str();
+        if (discovery_info.object_id_generator == MQTT_DEVICE_NAME_OBJECT_ID_GENERATOR) {
+          // node_name (max 31) + "_" (1) + object_id (max 128) + null
+          char object_id_full[ESPHOME_DEVICE_NAME_MAX_LEN + 1 + OBJECT_ID_MAX_LEN + 1];
+          buf_append_printf(object_id_full, sizeof(object_id_full), 0, "%s_%s", node_name.c_str(), object_id.c_str());
+          root[MQTT_OBJECT_ID] = object_id_full;
+        }
 
         const std::string &friendly_name_ref = App.get_friendly_name();
         const std::string &node_friendly_name = friendly_name_ref.empty() ? node_name : friendly_name_ref;
-        std::string node_area = App.get_area();
+        const char *node_area = App.get_area();
 
         JsonObject device_info = root[MQTT_DEVICE].to<JsonObject>();
         char mac[MAC_ADDRESS_BUFFER_SIZE];
@@ -221,18 +260,29 @@ bool MQTTComponent::send_discovery_() {
         device_info[MQTT_DEVICE_SW_VERSION] = ESPHOME_PROJECT_VERSION " (ESPHome " ESPHOME_VERSION ")";
         const char *model = std::strchr(ESPHOME_PROJECT_NAME, '.');
         device_info[MQTT_DEVICE_MODEL] = model == nullptr ? ESPHOME_BOARD : model + 1;
-        device_info[MQTT_DEVICE_MANUFACTURER] =
-            model == nullptr ? ESPHOME_PROJECT_NAME : std::string(ESPHOME_PROJECT_NAME, model - ESPHOME_PROJECT_NAME);
+        if (model == nullptr) {
+          device_info[MQTT_DEVICE_MANUFACTURER] = ESPHOME_PROJECT_NAME;
+        } else {
+          // Extract manufacturer (part before '.') using stack buffer to avoid heap allocation
+          // memcpy is used instead of strncpy since we know the exact length and strncpy
+          // would still require manual null-termination
+          char manufacturer[sizeof(ESPHOME_PROJECT_NAME)];
+          size_t len = model - ESPHOME_PROJECT_NAME;
+          memcpy(manufacturer, ESPHOME_PROJECT_NAME, len);
+          manufacturer[len] = '\0';
+          device_info[MQTT_DEVICE_MANUFACTURER] = manufacturer;
+        }
 #else
         static const char ver_fmt[] PROGMEM = ESPHOME_VERSION " (config hash 0x%08" PRIx32 ")";
+        // Buffer sized for format string expansion: ~4 bytes net growth from format specifier to 8 hex digits, plus
+        // safety margin
+        char version_buf[sizeof(ver_fmt) + 8];
 #ifdef USE_ESP8266
-        char fmt_buf[sizeof(ver_fmt)];
-        strcpy_P(fmt_buf, ver_fmt);
-        const char *fmt = fmt_buf;
+        snprintf_P(version_buf, sizeof(version_buf), ver_fmt, App.get_config_hash());
 #else
-        const char *fmt = ver_fmt;
+        snprintf(version_buf, sizeof(version_buf), ver_fmt, App.get_config_hash());
 #endif
-        device_info[MQTT_DEVICE_SW_VERSION] = str_sprintf(fmt, App.get_config_hash());
+        device_info[MQTT_DEVICE_SW_VERSION] = version_buf;
         device_info[MQTT_DEVICE_MODEL] = ESPHOME_BOARD;
 #if defined(USE_ESP8266) || defined(USE_ESP32)
         device_info[MQTT_DEVICE_MANUFACTURER] = "Espressif";
@@ -246,7 +296,7 @@ bool MQTTComponent::send_discovery_() {
         device_info[MQTT_DEVICE_MANUFACTURER] = "Host";
 #endif
 #endif
-        if (!node_area.empty()) {
+        if (node_area[0] != '\0') {
           device_info[MQTT_DEVICE_SUGGESTED_AREA] = node_area;
         }
 
@@ -288,7 +338,9 @@ void MQTTComponent::set_availability(std::string topic, std::string payload_avai
 }
 void MQTTComponent::disable_availability() { this->set_availability("", "", ""); }
 void MQTTComponent::call_setup() {
-  if (this->is_internal())
+  // Cache is_internal result once during setup - topics don't change after this
+  this->is_internal_ = this->compute_is_internal_();
+  if (this->is_internal_)
     return;
 
   this->setup();
@@ -340,26 +392,28 @@ StringRef MQTTComponent::get_default_object_id_to_(std::span<char, OBJECT_ID_MAX
 }
 StringRef MQTTComponent::get_icon_ref_() const { return this->get_entity()->get_icon_ref(); }
 bool MQTTComponent::is_disabled_by_default_() const { return this->get_entity()->is_disabled_by_default(); }
-bool MQTTComponent::is_internal() {
+bool MQTTComponent::compute_is_internal_() {
   if (this->custom_state_topic_.has_value()) {
-    // If the custom state_topic is null, return true as it is internal and should not publish
+    // If the custom state_topic is empty, return true as it is internal and should not publish
     // else, return false, as it is explicitly set to a topic, so it is not internal and should publish
-    return this->get_state_topic_().empty();
+    // Using is_empty() avoids heap allocation for non-lambda cases
+    return this->custom_state_topic_.is_empty();
   }
 
   if (this->custom_command_topic_.has_value()) {
-    // If the custom command_topic is null, return true as it is internal and should not publish
+    // If the custom command_topic is empty, return true as it is internal and should not publish
     // else, return false, as it is explicitly set to a topic, so it is not internal and should publish
-    return this->get_command_topic_().empty();
+    // Using is_empty() avoids heap allocation for non-lambda cases
+    return this->custom_command_topic_.is_empty();
   }
 
-  // No custom topics have been set
-  if (this->get_default_topic_for_("").empty()) {
-    // If the default topic prefix is null, then the component, by default, is internal and should not publish
+  // No custom topics have been set - check topic_prefix directly to avoid allocation
+  if (global_mqtt_client->get_topic_prefix().empty()) {
+    // If the default topic prefix is empty, then the component, by default, is internal and should not publish
     return true;
   }
 
-  // Use ESPHome's component internal state if topic_prefix is not null with no custom state_topic or command_topic
+  // Use ESPHome's component internal state if topic_prefix is not empty with no custom state_topic or command_topic
   return this->get_entity()->is_internal();
 }
 

esphome/components/mqtt/mqtt_component.h

@@ -20,17 +20,22 @@ struct SendDiscoveryConfig {
   bool command_topic{true};  ///< If the command topic should be included. Default to true.
 };
 
-// Max lengths for stack-based topic building (must match mqtt_component.cpp)
+// Max lengths for stack-based topic building.
+// These limits are enforced at Python config validation time in mqtt/__init__.py
+// using cv.Length() validators for topic_prefix and discovery_prefix.
+// This ensures the stack buffers are always large enough.
 static constexpr size_t MQTT_COMPONENT_TYPE_MAX_LEN = 20;
 static constexpr size_t MQTT_SUFFIX_MAX_LEN = 32;
+static constexpr size_t MQTT_TOPIC_PREFIX_MAX_LEN = 64;  // Validated in Python: cv.Length(max=64)
+// Stack buffer size - safe because all inputs are length-validated at config time
+// Format: prefix + "/" + type + "/" + object_id + "/" + suffix + null
+static constexpr size_t MQTT_DEFAULT_TOPIC_MAX_LEN =
+    MQTT_TOPIC_PREFIX_MAX_LEN + 1 + MQTT_COMPONENT_TYPE_MAX_LEN + 1 + OBJECT_ID_MAX_LEN + 1 + MQTT_SUFFIX_MAX_LEN + 1;
 
-#define LOG_MQTT_COMPONENT(state_topic, command_topic) \
-  if (state_topic) { \
-    ESP_LOGCONFIG(TAG, "  State Topic: '%s'", this->get_state_topic_().c_str()); \
-  } \
-  if (command_topic) { \
-    ESP_LOGCONFIG(TAG, "  Command Topic: '%s'", this->get_command_topic_().c_str()); \
-  }
+class MQTTComponent;  // Forward declaration
+void log_mqtt_component(const char *tag, MQTTComponent *obj, bool state_topic, bool command_topic);
+
+#define LOG_MQTT_COMPONENT(state_topic, command_topic) log_mqtt_component(TAG, this, state_topic, command_topic)
 
 // Macro to define component_type() with compile-time length verification
 // Usage: MQTT_COMPONENT_TYPE(MQTTSensorComponent, "sensor")
@@ -74,6 +79,8 @@ static constexpr size_t MQTT_SUFFIX_MAX_LEN = 32;
  * a clean separation.
  */
 class MQTTComponent : public Component {
+  friend void log_mqtt_component(const char *tag, MQTTComponent *obj, bool state_topic, bool command_topic);
+
  public:
   /// Constructs a MQTTComponent.
   explicit MQTTComponent();
@@ -88,7 +95,8 @@ class MQTTComponent : public Component {
 
   virtual bool send_initial_state() = 0;
 
-  virtual bool is_internal();
+  /// Returns cached is_internal result (computed once during setup).
+  bool is_internal() const { return this->is_internal_; }
 
   /// Set QOS for state messages.
   void set_qos(uint8_t qos);
@@ -179,7 +187,16 @@ class MQTTComponent : public Component {
   /// Helper method to get the discovery topic for this component.
   std::string get_discovery_topic_(const MQTTDiscoveryInfo &discovery_info) const;
 
-  /** Get this components state/command/... topic.
+  /** Get this components state/command/... topic into a buffer.
+   *
+   * @param buf The buffer to write to (must be exactly MQTT_DEFAULT_TOPIC_MAX_LEN).
+   * @param suffix The suffix/key such as "state" or "command".
+   * @return StringRef pointing to the buffer with the topic.
+   */
+  StringRef get_default_topic_for_to_(std::span<char, MQTT_DEFAULT_TOPIC_MAX_LEN> buf, const char *suffix,
+                                      size_t suffix_len) const;
+
+  /** Get this components state/command/... topic (allocates std::string).
    *
    * @param suffix The suffix/key such as "state" or "command".
    * @return The full topic.
@@ -200,10 +217,20 @@ class MQTTComponent : public Component {
   /// Get whether the underlying Entity is disabled by default
   bool is_disabled_by_default_() const;
 
-  /// Get the MQTT topic that new states will be shared to.
+  /// Get the MQTT state topic into a buffer (no heap allocation for non-lambda custom topics).
+  /// @param buf Buffer of exactly MQTT_DEFAULT_TOPIC_MAX_LEN bytes.
+  /// @return StringRef pointing to the topic in the buffer.
+  StringRef get_state_topic_to_(std::span<char, MQTT_DEFAULT_TOPIC_MAX_LEN> buf) const;
+
+  /// Get the MQTT command topic into a buffer (no heap allocation for non-lambda custom topics).
+  /// @param buf Buffer of exactly MQTT_DEFAULT_TOPIC_MAX_LEN bytes.
+  /// @return StringRef pointing to the topic in the buffer.
+  StringRef get_command_topic_to_(std::span<char, MQTT_DEFAULT_TOPIC_MAX_LEN> buf) const;
+
+  /// Get the MQTT topic that new states will be shared to (allocates std::string).
   std::string get_state_topic_() const;
 
-  /// Get the MQTT topic for listening to commands.
+  /// Get the MQTT topic for listening to commands (allocates std::string).
   std::string get_command_topic_() const;
 
   bool is_connected_() const;
@@ -221,12 +248,18 @@ class MQTTComponent : public Component {
 
   std::unique_ptr<Availability> availability_;
 
-  bool command_retain_{false};
-  bool retain_{true};
-  uint8_t qos_{0};
-  uint8_t subscribe_qos_{0};
-  bool discovery_enabled_{true};
-  bool resend_state_{false};
+  // Packed bitfields - QoS values are 0-2, bools are flags
+  uint8_t qos_ : 2 {0};
+  uint8_t subscribe_qos_ : 2 {0};
+  bool command_retain_ : 1 {false};
+  bool retain_ : 1 {true};
+  bool discovery_enabled_ : 1 {true};
+  bool resend_state_ : 1 {false};
+  bool is_internal_ : 1 {false};  ///< Cached result of compute_is_internal_(), set during setup
+
+  /// Compute is_internal status based on topics and entity state.
+  /// Called once during setup to cache the result.
+  bool compute_is_internal_();
 };
 
 }  // namespace esphome::mqtt

esphome/components/mqtt/mqtt_cover.cpp

@@ -51,7 +51,7 @@ void MQTTCoverComponent::dump_config() {
   ESP_LOGCONFIG(TAG, "MQTT cover '%s':", this->cover_->get_name().c_str());
   auto traits = this->cover_->get_traits();
   bool has_command_topic = traits.get_supports_position() || !traits.get_supports_tilt();
-  LOG_MQTT_COMPONENT(true, has_command_topic)
+  LOG_MQTT_COMPONENT(true, has_command_topic);
   if (traits.get_supports_position()) {
     ESP_LOGCONFIG(TAG,
                   "  Position State Topic: '%s'\n"

esphome/components/mqtt/mqtt_date.cpp

@@ -36,7 +36,7 @@ void MQTTDateComponent::setup() {
 
 void MQTTDateComponent::dump_config() {
   ESP_LOGCONFIG(TAG, "MQTT Date '%s':", this->date_->get_name().c_str());
-  LOG_MQTT_COMPONENT(true, true)
+  LOG_MQTT_COMPONENT(true, true);
 }
 
 MQTT_COMPONENT_TYPE(MQTTDateComponent, "date")

esphome/components/mqtt/mqtt_datetime.cpp

@@ -47,7 +47,7 @@ void MQTTDateTimeComponent::setup() {
 
 void MQTTDateTimeComponent::dump_config() {
   ESP_LOGCONFIG(TAG, "MQTT DateTime '%s':", this->datetime_->get_name().c_str());
-  LOG_MQTT_COMPONENT(true, true)
+  LOG_MQTT_COMPONENT(true, true);
 }
 
 MQTT_COMPONENT_TYPE(MQTTDateTimeComponent, "datetime")

esphome/components/mqtt/mqtt_fan.cpp

@@ -175,7 +175,7 @@ bool MQTTFanComponent::publish_state() {
   auto traits = this->state_->get_traits();
   if (traits.supports_speed()) {
     char buf[12];
-    int len = snprintf(buf, sizeof(buf), "%d", this->state_->speed);
+    size_t len = buf_append_printf(buf, sizeof(buf), 0, "%d", this->state_->speed);
     bool success = this->publish(this->get_speed_level_state_topic(), buf, len);
     failed = failed || !success;
   }

esphome/components/mqtt/mqtt_light.cpp

@@ -90,7 +90,7 @@ void MQTTJSONLightComponent::send_discovery(JsonObject root, mqtt::SendDiscovery
 bool MQTTJSONLightComponent::send_initial_state() { return this->publish_state_(); }
 void MQTTJSONLightComponent::dump_config() {
   ESP_LOGCONFIG(TAG, "MQTT Light '%s':", this->state_->get_name().c_str());
-  LOG_MQTT_COMPONENT(true, true)
+  LOG_MQTT_COMPONENT(true, true);
 }
 
 }  // namespace esphome::mqtt

esphome/components/mqtt/mqtt_number.cpp

@@ -30,7 +30,7 @@ void MQTTNumberComponent::setup() {
 
 void MQTTNumberComponent::dump_config() {
   ESP_LOGCONFIG(TAG, "MQTT Number '%s':", this->number_->get_name().c_str());
-  LOG_MQTT_COMPONENT(true, false)
+  LOG_MQTT_COMPONENT(true, false);
 }
 
 MQTT_COMPONENT_TYPE(MQTTNumberComponent, "number")
@@ -75,7 +75,7 @@ bool MQTTNumberComponent::send_initial_state() {
 }
 bool MQTTNumberComponent::publish_state(float value) {
   char buffer[64];
-  snprintf(buffer, sizeof(buffer), "%f", value);
+  buf_append_printf(buffer, sizeof(buffer), 0, "%f", value);
   return this->publish(this->get_state_topic_(), buffer);
 }
 

esphome/components/mqtt/mqtt_select.cpp

@@ -25,7 +25,7 @@ void MQTTSelectComponent::setup() {
 
 void MQTTSelectComponent::dump_config() {
   ESP_LOGCONFIG(TAG, "MQTT Select '%s':", this->select_->get_name().c_str());
-  LOG_MQTT_COMPONENT(true, false)
+  LOG_MQTT_COMPONENT(true, false);
 }
 
 MQTT_COMPONENT_TYPE(MQTTSelectComponent, "select")

esphome/components/mqtt/mqtt_sensor.cpp

@@ -28,7 +28,7 @@ void MQTTSensorComponent::dump_config() {
   if (this->get_expire_after() > 0) {
     ESP_LOGCONFIG(TAG, "  Expire After: %" PRIu32 "s", this->get_expire_after() / 1000);
   }
-  LOG_MQTT_COMPONENT(true, false)
+  LOG_MQTT_COMPONENT(true, false);
 }
 
 MQTT_COMPONENT_TYPE(MQTTSensorComponent, "sensor")

esphome/components/mqtt/mqtt_text.cpp

@@ -26,7 +26,7 @@ void MQTTTextComponent::setup() {
 
 void MQTTTextComponent::dump_config() {
   ESP_LOGCONFIG(TAG, "MQTT text '%s':", this->text_->get_name().c_str());
-  LOG_MQTT_COMPONENT(true, true)
+  LOG_MQTT_COMPONENT(true, true);
 }
 
 MQTT_COMPONENT_TYPE(MQTTTextComponent, "text")

esphome/components/mqtt/mqtt_time.cpp

@@ -36,7 +36,7 @@ void MQTTTimeComponent::setup() {
 
 void MQTTTimeComponent::dump_config() {
   ESP_LOGCONFIG(TAG, "MQTT Time '%s':", this->time_->get_name().c_str());
-  LOG_MQTT_COMPONENT(true, true)
+  LOG_MQTT_COMPONENT(true, true);
 }
 
 MQTT_COMPONENT_TYPE(MQTTTimeComponent, "time")

esphome/components/mqtt/mqtt_valve.cpp

@@ -39,7 +39,7 @@ void MQTTValveComponent::dump_config() {
   ESP_LOGCONFIG(TAG, "MQTT valve '%s':", this->valve_->get_name().c_str());
   auto traits = this->valve_->get_traits();
   bool has_command_topic = traits.get_supports_position();
-  LOG_MQTT_COMPONENT(true, has_command_topic)
+  LOG_MQTT_COMPONENT(true, has_command_topic);
   if (traits.get_supports_position()) {
     ESP_LOGCONFIG(TAG,
                   "  Position State Topic: '%s'\n"

esphome/components/nextion/base_component.py

@@ -16,6 +16,7 @@ CONF_EXIT_REPARSE_ON_START = "exit_reparse_on_start"
 CONF_FONT_ID = "font_id"
 CONF_FOREGROUND_PRESSED_COLOR = "foreground_pressed_color"
 CONF_MAX_COMMANDS_PER_LOOP = "max_commands_per_loop"
+CONF_MAX_QUEUE_AGE = "max_queue_age"
 CONF_MAX_QUEUE_SIZE = "max_queue_size"
 CONF_ON_BUFFER_OVERFLOW = "on_buffer_overflow"
 CONF_ON_PAGE = "on_page"
@@ -25,6 +26,7 @@ CONF_ON_WAKE = "on_wake"
 CONF_PRECISION = "precision"
 CONF_SKIP_CONNECTION_HANDSHAKE = "skip_connection_handshake"
 CONF_START_UP_PAGE = "start_up_page"
+CONF_STARTUP_OVERRIDE_MS = "startup_override_ms"
 CONF_TFT_URL = "tft_url"
 CONF_TOUCH_SLEEP_TIMEOUT = "touch_sleep_timeout"
 CONF_VARIABLE_NAME = "variable_name"

esphome/components/nextion/display.py

@@ -23,6 +23,7 @@ from .base_component import (
     CONF_DUMP_DEVICE_INFO,
     CONF_EXIT_REPARSE_ON_START,
     CONF_MAX_COMMANDS_PER_LOOP,
+    CONF_MAX_QUEUE_AGE,
     CONF_MAX_QUEUE_SIZE,
     CONF_ON_BUFFER_OVERFLOW,
     CONF_ON_PAGE,
@@ -31,6 +32,7 @@ from .base_component import (
     CONF_ON_WAKE,
     CONF_SKIP_CONNECTION_HANDSHAKE,
     CONF_START_UP_PAGE,
+    CONF_STARTUP_OVERRIDE_MS,
     CONF_TFT_URL,
     CONF_TOUCH_SLEEP_TIMEOUT,
     CONF_WAKE_UP_PAGE,
@@ -65,6 +67,12 @@ CONFIG_SCHEMA = (
             ),
             cv.Optional(CONF_DUMP_DEVICE_INFO, default=False): cv.boolean,
             cv.Optional(CONF_EXIT_REPARSE_ON_START, default=False): cv.boolean,
+            cv.Optional(CONF_MAX_QUEUE_AGE, default="8000ms"): cv.All(
+                cv.positive_time_period_milliseconds,
+                cv.Range(
+                    min=TimePeriod(milliseconds=0), max=TimePeriod(milliseconds=65535)
+                ),
+            ),
             cv.Optional(CONF_MAX_COMMANDS_PER_LOOP): cv.uint16_t,
             cv.Optional(CONF_MAX_QUEUE_SIZE): cv.positive_int,
             cv.Optional(CONF_ON_BUFFER_OVERFLOW): automation.validate_automation(
@@ -100,6 +108,12 @@ CONFIG_SCHEMA = (
                 }
             ),
             cv.Optional(CONF_SKIP_CONNECTION_HANDSHAKE, default=False): cv.boolean,
+            cv.Optional(CONF_STARTUP_OVERRIDE_MS, default="8000ms"): cv.All(
+                cv.positive_time_period_milliseconds,
+                cv.Range(
+                    min=TimePeriod(milliseconds=0), max=TimePeriod(milliseconds=65535)
+                ),
+            ),
             cv.Optional(CONF_START_UP_PAGE): cv.uint8_t,
             cv.Optional(CONF_TFT_URL): cv.url,
             cv.Optional(CONF_TOUCH_SLEEP_TIMEOUT): cv.Any(
@@ -138,6 +152,8 @@ async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     await uart.register_uart_device(var, config)
 
+    cg.add(var.set_max_queue_age(config[CONF_MAX_QUEUE_AGE]))
+
     if max_queue_size := config.get(CONF_MAX_QUEUE_SIZE):
         cg.add_define("USE_NEXTION_MAX_QUEUE_SIZE")
         cg.add(var.set_max_queue_size(max_queue_size))
@@ -146,6 +162,8 @@ async def to_code(config):
         cg.add_define("USE_NEXTION_COMMAND_SPACING")
         cg.add(var.set_command_spacing(command_spacing.total_milliseconds))
 
+    cg.add(var.set_startup_override_ms(config[CONF_STARTUP_OVERRIDE_MS]))
+
     if CONF_BRIGHTNESS in config:
         cg.add(var.set_brightness(config[CONF_BRIGHTNESS]))
 

esphome/components/nextion/nextion.cpp

@@ -152,21 +152,25 @@ void Nextion::dump_config() {
 #else  // USE_NEXTION_CONFIG_SKIP_CONNECTION_HANDSHAKE
   ESP_LOGCONFIG(TAG,
 #ifdef USE_NEXTION_CONFIG_DUMP_DEVICE_INFO
-                "  Device Model:   %s\n"
-                "  FW Version:     %s\n"
-                "  Serial Number:  %s\n"
-                "  Flash Size:     %s\n"
+                "  Device Model: %s\n"
+                "  FW Version: %s\n"
+                "  Serial Number: %s\n"
+                "  Flash Size: %s\n"
+                "  Max queue age: %u ms\n"
+                "  Startup override: %u ms\n",
 #endif  // USE_NEXTION_CONFIG_DUMP_DEVICE_INFO
 #ifdef USE_NEXTION_CONFIG_EXIT_REPARSE_ON_START
-                "  Exit reparse:   YES\n"
+                "  Exit reparse: YES\n"
 #endif  // USE_NEXTION_CONFIG_EXIT_REPARSE_ON_START
-                "  Wake On Touch:  %s\n"
-                "  Touch Timeout:  %" PRIu16,
+                "  Wake On Touch: %s\n"
+                "  Touch Timeout: %" PRIu16,
 #ifdef USE_NEXTION_CONFIG_DUMP_DEVICE_INFO
                 this->device_model_.c_str(), this->firmware_version_.c_str(), this->serial_number_.c_str(),
-                this->flash_size_.c_str(),
+                this->flash_size_.c_str(), this->max_q_age_ms_,
+                this->startup_override_ms_
 #endif  // USE_NEXTION_CONFIG_DUMP_DEVICE_INFO
-                YESNO(this->connection_state_.auto_wake_on_touch_), this->touch_sleep_timeout_);
+                    YESNO(this->connection_state_.auto_wake_on_touch_),
+                this->touch_sleep_timeout_);
 #endif  // USE_NEXTION_CONFIG_SKIP_CONNECTION_HANDSHAKE
 
 #ifdef USE_NEXTION_MAX_COMMANDS_PER_LOOP
@@ -174,21 +178,21 @@ void Nextion::dump_config() {
 #endif  // USE_NEXTION_MAX_COMMANDS_PER_LOOP
 
   if (this->wake_up_page_ != 255) {
-    ESP_LOGCONFIG(TAG, "  Wake Up Page:   %u", this->wake_up_page_);
+    ESP_LOGCONFIG(TAG, "  Wake Up Page: %u", this->wake_up_page_);
   }
 
 #ifdef USE_NEXTION_CONF_START_UP_PAGE
   if (this->start_up_page_ != 255) {
-    ESP_LOGCONFIG(TAG, "  Start Up Page:  %u", this->start_up_page_);
+    ESP_LOGCONFIG(TAG, "  Start Up Page: %u", this->start_up_page_);
   }
 #endif  // USE_NEXTION_CONF_START_UP_PAGE
 
 #ifdef USE_NEXTION_COMMAND_SPACING
-  ESP_LOGCONFIG(TAG, "  Cmd spacing:      %u ms", this->command_pacer_.get_spacing());
+  ESP_LOGCONFIG(TAG, "  Cmd spacing: %u ms", this->command_pacer_.get_spacing());
 #endif  // USE_NEXTION_COMMAND_SPACING
 
 #ifdef USE_NEXTION_MAX_QUEUE_SIZE
-  ESP_LOGCONFIG(TAG, "  Max queue size:   %zu", this->max_queue_size_);
+  ESP_LOGCONFIG(TAG, "  Max queue size: %zu", this->max_queue_size_);
 #endif
 }
 
@@ -336,7 +340,8 @@ void Nextion::loop() {
     if (this->started_ms_ == 0)
       this->started_ms_ = App.get_loop_component_start_time();
 
-    if (this->started_ms_ + this->startup_override_ms_ < App.get_loop_component_start_time()) {
+    if (this->startup_override_ms_ > 0 &&
+        this->started_ms_ + this->startup_override_ms_ < App.get_loop_component_start_time()) {
       ESP_LOGV(TAG, "Manual ready set");
       this->connection_state_.nextion_reports_is_setup_ = true;
     }
@@ -845,7 +850,8 @@ void Nextion::process_nextion_commands_() {
 
   const uint32_t ms = App.get_loop_component_start_time();
 
-  if (!this->nextion_queue_.empty() && this->nextion_queue_.front()->queue_time + this->max_q_age_ms_ < ms) {
+  if (this->max_q_age_ms_ > 0 && !this->nextion_queue_.empty() &&
+      this->nextion_queue_.front()->queue_time + this->max_q_age_ms_ < ms) {
     for (size_t i = 0; i < this->nextion_queue_.size(); i++) {
       NextionComponentBase *component = this->nextion_queue_[i]->component;
       if (this->nextion_queue_[i]->queue_time + this->max_q_age_ms_ < ms) {

esphome/components/nextion/nextion.h

@@ -1309,6 +1309,30 @@ class Nextion : public NextionBase, public PollingComponent, public uart::UARTDe
    */
   bool is_connected() { return this->connection_state_.is_connected_; }
 
+  /**
+   * @brief Set the maximum age for queue items
+   * @param age_ms Maximum age in milliseconds before queue items are removed
+   */
+  inline void set_max_queue_age(uint16_t age_ms) { this->max_q_age_ms_ = age_ms; }
+
+  /**
+   * @brief Get the maximum age for queue items
+   * @return Maximum age in milliseconds
+   */
+  inline uint16_t get_max_queue_age() const { return this->max_q_age_ms_; }
+
+  /**
+   * @brief Set the startup override timeout
+   * @param timeout_ms Time in milliseconds to wait before forcing setup complete
+   */
+  inline void set_startup_override_ms(uint16_t timeout_ms) { this->startup_override_ms_ = timeout_ms; }
+
+  /**
+   * @brief Get the startup override timeout
+   * @return Startup override timeout in milliseconds
+   */
+  inline uint16_t get_startup_override_ms() const { return this->startup_override_ms_; }
+
  protected:
 #ifdef USE_NEXTION_MAX_COMMANDS_PER_LOOP
   uint16_t max_commands_per_loop_{1000};
@@ -1479,9 +1503,10 @@ class Nextion : public NextionBase, public PollingComponent, public uart::UARTDe
   void reset_(bool reset_nextion = true);
 
   std::string command_data_;
-  const uint16_t startup_override_ms_ = 8000;
-  const uint16_t max_q_age_ms_ = 8000;
   uint32_t started_ms_ = 0;
+
+  uint16_t startup_override_ms_ = 8000;  ///< Timeout before forcing setup complete
+  uint16_t max_q_age_ms_ = 8000;         ///< Maximum age for queue items in ms
 };
 
 }  // namespace nextion

esphome/components/pcd8544/display.py

@@ -44,7 +44,7 @@ async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
 
     await display.register_display(var, config)
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
 
     dc = await cg.gpio_pin_expression(config[CONF_DC_PIN])
     cg.add(var.set_dc_pin(dc))

esphome/components/qspi_dbi/display.py

@@ -161,7 +161,7 @@ CONFIG_SCHEMA = cv.All(
 async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     await display.register_display(var, config)
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
 
     chip = DriverChip.chips[config[CONF_MODEL]]
     if chip.initsequence:

esphome/components/sensor/__init__.py

@@ -9,6 +9,7 @@ from esphome.const import (
     CONF_ABOVE,
     CONF_ACCURACY_DECIMALS,
     CONF_ALPHA,
+    CONF_BASELINE,
     CONF_BELOW,
     CONF_CALIBRATION,
     CONF_DEVICE_CLASS,
@@ -38,7 +39,6 @@ from esphome.const import (
     CONF_TIMEOUT,
     CONF_TO,
     CONF_TRIGGER_ID,
-    CONF_TYPE,
     CONF_UNIT_OF_MEASUREMENT,
     CONF_VALUE,
     CONF_WEB_SERVER,
@@ -107,7 +107,7 @@ from esphome.const import (
 )
 from esphome.core import CORE, CoroPriority, coroutine_with_priority
 from esphome.core.entity_helpers import entity_duplicate_validator, setup_entity
-from esphome.cpp_generator import MockObjClass
+from esphome.cpp_generator import MockObj, MockObjClass
 from esphome.util import Registry
 
 CODEOWNERS = ["@esphome/core"]
@@ -574,38 +574,56 @@ async def lambda_filter_to_code(config, filter_id):
     return automation.new_lambda_pvariable(filter_id, lambda_, StatelessLambdaFilter)
 
 
-DELTA_SCHEMA = cv.Schema(
-    {
-        cv.Required(CONF_VALUE): cv.positive_float,
-        cv.Optional(CONF_TYPE, default="absolute"): cv.one_of(
-            "absolute", "percentage", lower=True
-        ),
-    }
+def validate_delta_value(value):
+    if isinstance(value, str) and value.endswith("%"):
+        # Check it's a well-formed percentage, but return the string as-is
+        try:
+            cv.positive_float(value[:-1])
+            return value
+        except cv.Invalid as exc:
+            raise cv.Invalid("Malformed delta % value") from exc
+    return cv.positive_float(value)
+
+
+# This ideally would be done with `cv.maybe_simple_value` but it doesn't seem to respect the default for min_value.
+DELTA_SCHEMA = cv.Any(
+    cv.All(
+        {
+            # Ideally this would be 'default=float("inf")' but it doesn't translate well to C++
+            cv.Optional(CONF_MAX_VALUE): validate_delta_value,
+            cv.Optional(CONF_MIN_VALUE, default="0.0"): validate_delta_value,
+            cv.Optional(CONF_BASELINE): cv.templatable(cv.float_),
+        },
+        cv.has_at_least_one_key(CONF_MAX_VALUE, CONF_MIN_VALUE),
+    ),
+    validate_delta_value,
 )
 
 
-def validate_delta(config):
-    try:
-        value = cv.positive_float(config)
-        return DELTA_SCHEMA({CONF_VALUE: value, CONF_TYPE: "absolute"})
-    except cv.Invalid:
-        pass
-    try:
-        value = cv.percentage(config)
-        return DELTA_SCHEMA({CONF_VALUE: value, CONF_TYPE: "percentage"})
-    except cv.Invalid:
-        pass
-    raise cv.Invalid("Delta filter requires a positive number or percentage value.")
+def _get_delta(value):
+    if isinstance(value, str):
+        assert value.endswith("%")
+        return 0.0, float(value[:-1])
+    return value, 0.0
 
 
-@FILTER_REGISTRY.register("delta", DeltaFilter, cv.Any(DELTA_SCHEMA, validate_delta))
+@FILTER_REGISTRY.register("delta", DeltaFilter, DELTA_SCHEMA)
 async def delta_filter_to_code(config, filter_id):
-    percentage = config[CONF_TYPE] == "percentage"
-    return cg.new_Pvariable(
-        filter_id,
-        config[CONF_VALUE],
-        percentage,
-    )
+    # The config could be just the min_value, or it could be a dict.
+    max = MockObj("std::numeric_limits<float>::infinity()"), 0
+    if isinstance(config, dict):
+        min = _get_delta(config[CONF_MIN_VALUE])
+        if CONF_MAX_VALUE in config:
+            max = _get_delta(config[CONF_MAX_VALUE])
+    else:
+        min = _get_delta(config)
+    var = cg.new_Pvariable(filter_id, *min, *max)
+    if isinstance(config, dict) and (baseline_lambda := config.get(CONF_BASELINE)):
+        baseline = await cg.process_lambda(
+            baseline_lambda, [(float, "x")], return_type=float
+        )
+        cg.add(var.set_baseline(baseline))
+    return var
 
 
 @FILTER_REGISTRY.register("or", OrFilter, validate_filters)

esphome/components/sensor/filter.cpp

@@ -291,22 +291,27 @@ optional<float> ThrottleWithPriorityFilter::new_value(float value) {
 }
 
 // DeltaFilter
-DeltaFilter::DeltaFilter(float delta, bool percentage_mode)
-    : delta_(delta), current_delta_(delta), last_value_(NAN), percentage_mode_(percentage_mode) {}
+DeltaFilter::DeltaFilter(float min_a0, float min_a1, float max_a0, float max_a1)
+    : min_a0_(min_a0), min_a1_(min_a1), max_a0_(max_a0), max_a1_(max_a1) {}
+
+void DeltaFilter::set_baseline(float (*fn)(float)) { this->baseline_ = fn; }
+
 optional<float> DeltaFilter::new_value(float value) {
-  if (std::isnan(value)) {
-    if (std::isnan(this->last_value_)) {
-      return {};
-    } else {
-      return this->last_value_ = value;
-    }
+  // Always yield the first value.
+  if (std::isnan(this->last_value_)) {
+    this->last_value_ = value;
+    return value;
   }
-  float diff = fabsf(value - this->last_value_);
-  if (std::isnan(this->last_value_) || (diff > 0.0f && diff >= this->current_delta_)) {
-    if (this->percentage_mode_) {
-      this->current_delta_ = fabsf(value * this->delta_);
-    }
-    return this->last_value_ = value;
+  // calculate min and max using the linear equation
+  float ref = this->baseline_(this->last_value_);
+  float min = fabsf(this->min_a0_ + ref * this->min_a1_);
+  float max = fabsf(this->max_a0_ + ref * this->max_a1_);
+  float delta = fabsf(value - ref);
+  // if there is no reference, e.g. for the first value, just accept this one,
+  // otherwise accept only if within range.
+  if (delta > min && delta <= max) {
+    this->last_value_ = value;
+    return value;
   }
   return {};
 }

esphome/components/sensor/filter.h

@@ -452,15 +452,21 @@ class HeartbeatFilter : public Filter, public Component {
 
 class DeltaFilter : public Filter {
  public:
-  explicit DeltaFilter(float delta, bool percentage_mode);
+  explicit DeltaFilter(float min_a0, float min_a1, float max_a0, float max_a1);
+
+  void set_baseline(float (*fn)(float));
 
   optional<float> new_value(float value) override;
 
  protected:
-  float delta_;
-  float current_delta_;
+  // These values represent linear equations for the min and max values but in practice only one of a0 and a1 will be
+  // non-zero Each limit is calculated as fabs(a0 + value * a1)
+
+  float min_a0_, min_a1_, max_a0_, max_a1_;
+  // default baseline is the previous value
+  float (*baseline_)(float) = [](float last_value) { return last_value; };
+
   float last_value_{NAN};
-  bool percentage_mode_;
 };
 
 class OrFilter : public Filter {

esphome/components/socket/socket.cpp

@@ -46,15 +46,15 @@ static inline const char *esphome_inet_ntop6(const void *addr, char *buf, size_t
 #endif
 
 // Format sockaddr into caller-provided buffer, returns length written (excluding null)
-static size_t format_sockaddr_to(const struct sockaddr_storage &storage, std::span<char, SOCKADDR_STR_LEN> buf) {
-  if (storage.ss_family == AF_INET) {
-    const auto *addr = reinterpret_cast<const struct sockaddr_in *>(&storage);
+size_t format_sockaddr_to(const struct sockaddr *addr_ptr, socklen_t len, std::span<char, SOCKADDR_STR_LEN> buf) {
+  if (addr_ptr->sa_family == AF_INET && len >= sizeof(const struct sockaddr_in)) {
+    const auto *addr = reinterpret_cast<const struct sockaddr_in *>(addr_ptr);
     if (esphome_inet_ntop4(&addr->sin_addr, buf.data(), buf.size()) != nullptr)
       return strlen(buf.data());
   }
 #if USE_NETWORK_IPV6
-  else if (storage.ss_family == AF_INET6) {
-    const auto *addr = reinterpret_cast<const struct sockaddr_in6 *>(&storage);
+  else if (addr_ptr->sa_family == AF_INET6 && len >= sizeof(sockaddr_in6)) {
+    const auto *addr = reinterpret_cast<const struct sockaddr_in6 *>(addr_ptr);
 #ifndef USE_SOCKET_IMPL_LWIP_TCP
     // Format IPv4-mapped IPv6 addresses as regular IPv4 (not supported on ESP8266 raw TCP)
     if (addr->sin6_addr.un.u32_addr[0] == 0 && addr->sin6_addr.un.u32_addr[1] == 0 &&
@@ -78,7 +78,7 @@ size_t Socket::getpeername_to(std::span<char, SOCKADDR_STR_LEN> buf) {
     buf[0] = '\0';
     return 0;
   }
-  return format_sockaddr_to(storage, buf);
+  return format_sockaddr_to(reinterpret_cast<struct sockaddr *>(&storage), len, buf);
 }
 
 size_t Socket::getsockname_to(std::span<char, SOCKADDR_STR_LEN> buf) {
@@ -88,7 +88,7 @@ size_t Socket::getsockname_to(std::span<char, SOCKADDR_STR_LEN> buf) {
     buf[0] = '\0';
     return 0;
   }
-  return format_sockaddr_to(storage, buf);
+  return format_sockaddr_to(reinterpret_cast<struct sockaddr *>(&storage), len, buf);
 }
 
 std::unique_ptr<Socket> socket_ip(int type, int protocol) {

esphome/components/socket/socket.h

@@ -102,6 +102,9 @@ inline socklen_t set_sockaddr(struct sockaddr *addr, socklen_t addrlen, const st
 /// Set a sockaddr to the any address and specified port for the IP version used by socket_ip().
 socklen_t set_sockaddr_any(struct sockaddr *addr, socklen_t addrlen, uint16_t port);
 
+/// Format sockaddr into caller-provided buffer, returns length written (excluding null)
+size_t format_sockaddr_to(const struct sockaddr *addr_ptr, socklen_t len, std::span<char, SOCKADDR_STR_LEN> buf);
+
 #if defined(USE_ESP8266) && defined(USE_SOCKET_IMPL_LWIP_TCP)
 /// Delay that can be woken early by socket activity.
 /// On ESP8266, lwip callbacks set a flag and call esp_schedule() to wake the delay.

esphome/components/spi/__init__.py

@@ -39,6 +39,7 @@ from esphome.const import (
 )
 from esphome.core import CORE, CoroPriority, coroutine_with_priority
 import esphome.final_validate as fv
+from esphome.types import ConfigType
 
 CODEOWNERS = ["@esphome/core", "@clydebarrow"]
 spi_ns = cg.esphome_ns.namespace("spi")
@@ -448,9 +449,13 @@ def spi_device_schema(
     )
 
 
-async def register_spi_device(var, config):
+async def register_spi_device(
+    var: cg.Pvariable, config: ConfigType, write_only: bool = False
+) -> None:
     parent = await cg.get_variable(config[CONF_SPI_ID])
     cg.add(var.set_spi_parent(parent))
+    if write_only:
+        cg.add(var.set_write_only(True))
     if cs_pin := config.get(CONF_CS_PIN):
         pin = await cg.gpio_pin_expression(cs_pin)
         cg.add(var.set_cs_pin(pin))

esphome/components/spi/spi_esp_idf.cpp

@@ -195,8 +195,11 @@ class SPIDelegateHw : public SPIDelegate {
     config.post_cb = nullptr;
     if (this->bit_order_ == BIT_ORDER_LSB_FIRST)
       config.flags |= SPI_DEVICE_BIT_LSBFIRST;
-    if (this->write_only_)
+    if (this->write_only_) {
       config.flags |= SPI_DEVICE_HALFDUPLEX | SPI_DEVICE_NO_DUMMY;
+      ESP_LOGD(TAG, "SPI device with CS pin %d using half-duplex mode (write-only)",
+               Utility::get_pin_no(this->cs_pin_));
+    }
     esp_err_t const err = spi_bus_add_device(this->channel_, &config, &this->handle_);
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Add device failed - err %X", err);

esphome/components/ssd1306_spi/display.py

@@ -32,7 +32,7 @@ FINAL_VALIDATE_SCHEMA = spi.final_validate_device_schema(
 async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     await ssd1306_base.setup_ssd1306(var, config)
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
 
     dc = await cg.gpio_pin_expression(config[CONF_DC_PIN])
     cg.add(var.set_dc_pin(dc))

esphome/components/ssd1322_spi/display.py

@@ -32,7 +32,7 @@ FINAL_VALIDATE_SCHEMA = spi.final_validate_device_schema(
 async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     await ssd1322_base.setup_ssd1322(var, config)
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
 
     dc = await cg.gpio_pin_expression(config[CONF_DC_PIN])
     cg.add(var.set_dc_pin(dc))

esphome/components/ssd1325_spi/display.py

@@ -32,7 +32,7 @@ FINAL_VALIDATE_SCHEMA = spi.final_validate_device_schema(
 async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     await ssd1325_base.setup_ssd1325(var, config)
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
 
     dc = await cg.gpio_pin_expression(config[CONF_DC_PIN])
     cg.add(var.set_dc_pin(dc))

esphome/components/ssd1327_spi/display.py

@@ -32,7 +32,7 @@ FINAL_VALIDATE_SCHEMA = spi.final_validate_device_schema(
 async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     await ssd1327_base.setup_ssd1327(var, config)
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
 
     dc = await cg.gpio_pin_expression(config[CONF_DC_PIN])
     cg.add(var.set_dc_pin(dc))

esphome/components/ssd1331_spi/display.py

@@ -32,7 +32,7 @@ FINAL_VALIDATE_SCHEMA = spi.final_validate_device_schema(
 async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     await ssd1331_base.setup_ssd1331(var, config)
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
 
     dc = await cg.gpio_pin_expression(config[CONF_DC_PIN])
     cg.add(var.set_dc_pin(dc))

esphome/components/ssd1351_spi/display.py

@@ -32,7 +32,7 @@ FINAL_VALIDATE_SCHEMA = spi.final_validate_device_schema(
 async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     await ssd1351_base.setup_ssd1351(var, config)
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
 
     dc = await cg.gpio_pin_expression(config[CONF_DC_PIN])
     cg.add(var.set_dc_pin(dc))

esphome/components/st7567_spi/display.py

@@ -32,7 +32,7 @@ FINAL_VALIDATE_SCHEMA = spi.final_validate_device_schema(
 async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     await st7567_base.setup_st7567(var, config)
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
 
     dc = await cg.gpio_pin_expression(config[CONF_DC_PIN])
     cg.add(var.set_dc_pin(dc))

esphome/components/st7701s/display.py

@@ -173,7 +173,7 @@ FINAL_VALIDATE_SCHEMA = spi.final_validate_device_schema(
 async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     await display.register_display(var, config)
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
 
     sequence = []
     for seq in config[CONF_INIT_SEQUENCE]:

esphome/components/st7735/display.py

@@ -99,7 +99,7 @@ async def to_code(config):
         config[CONF_INVERT_COLORS],
     )
     await setup_st7735(var, config)
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
 
     dc = await cg.gpio_pin_expression(config[CONF_DC_PIN])
     cg.add(var.set_dc_pin(dc))

esphome/components/st7789v/display.py

@@ -177,7 +177,7 @@ FINAL_VALIDATE_SCHEMA = spi.final_validate_device_schema(
 async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     await display.register_display(var, config)
-    await spi.register_spi_device(var, config)
+    await spi.register_spi_device(var, config, write_only=True)
 
     cg.add(var.set_model_str(config[CONF_MODEL]))