diff --git a/.github/workflows/auto-label-pr.yml b/.github/workflows/auto-label-pr.yml
index fb284c9d8c..8d8e08a5fc 100644
--- a/.github/workflows/auto-label-pr.yml
+++ b/.github/workflows/auto-label-pr.yml
@@ -22,7 +22,7 @@ jobs:
     if: github.event.action != 'labeled' || github.event.sender.type != 'Bot'
     steps:
       - name: Checkout
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
       - name: Generate a token
         id: generate-token
diff --git a/.github/workflows/ci-api-proto.yml b/.github/workflows/ci-api-proto.yml
index be5af1aff1..b377ca76d8 100644
--- a/.github/workflows/ci-api-proto.yml
+++ b/.github/workflows/ci-api-proto.yml
@@ -21,7 +21,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - name: Set up Python
         uses: actions/setup-python@e797f83bcb11b83ae66e0230d6156d7c80228e7c # v6.0.0
         with:
diff --git a/.github/workflows/ci-clang-tidy-hash.yml b/.github/workflows/ci-clang-tidy-hash.yml
index aebf07949d..9556b99015 100644
--- a/.github/workflows/ci-clang-tidy-hash.yml
+++ b/.github/workflows/ci-clang-tidy-hash.yml
@@ -21,7 +21,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
       - name: Set up Python
         uses: actions/setup-python@e797f83bcb11b83ae66e0230d6156d7c80228e7c # v6.0.0
diff --git a/.github/workflows/ci-docker.yml b/.github/workflows/ci-docker.yml
index 9bb983b993..5287d92b10 100644
--- a/.github/workflows/ci-docker.yml
+++ b/.github/workflows/ci-docker.yml
@@ -43,7 +43,7 @@ jobs:
           - "docker"
           # - "lint"
     steps:
-      - uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+      - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - name: Set up Python
         uses: actions/setup-python@e797f83bcb11b83ae66e0230d6156d7c80228e7c # v6.0.0
         with:
diff --git a/.github/workflows/ci-memory-impact-comment.yml b/.github/workflows/ci-memory-impact-comment.yml
index c82ae30f55..6ca58e252e 100644
--- a/.github/workflows/ci-memory-impact-comment.yml
+++ b/.github/workflows/ci-memory-impact-comment.yml
@@ -49,7 +49,7 @@ jobs:
 
       - name: Check out code from base repository
         if: steps.pr.outputs.skip != 'true'
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
         with:
           # Always check out from the base repository (esphome/esphome), never from forks
           # Use the PR's target branch to ensure we run trusted code from the main repo
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 5293c62d34..9c2fab0912 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -36,7 +36,7 @@ jobs:
       cache-key: ${{ steps.cache-key.outputs.key }}
     steps:
       - name: Check out code from GitHub
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - name: Generate cache-key
         id: cache-key
         run: echo key="${{ hashFiles('requirements.txt', 'requirements_test.txt', '.pre-commit-config.yaml') }}" >> $GITHUB_OUTPUT
@@ -70,7 +70,7 @@ jobs:
     if: needs.determine-jobs.outputs.python-linters == 'true'
     steps:
       - name: Check out code from GitHub
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - name: Restore Python
         uses: ./.github/actions/restore-python
         with:
@@ -91,7 +91,7 @@ jobs:
       - common
     steps:
       - name: Check out code from GitHub
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - name: Restore Python
         uses: ./.github/actions/restore-python
         with:
@@ -132,7 +132,7 @@ jobs:
       - common
     steps:
       - name: Check out code from GitHub
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - name: Restore Python
         id: restore-python
         uses: ./.github/actions/restore-python
@@ -183,7 +183,7 @@ jobs:
       component-test-batches: ${{ steps.determine.outputs.component-test-batches }}
     steps:
       - name: Check out code from GitHub
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
         with:
           # Fetch enough history to find the merge base
           fetch-depth: 2
@@ -237,7 +237,7 @@ jobs:
     if: needs.determine-jobs.outputs.integration-tests == 'true'
     steps:
       - name: Check out code from GitHub
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - name: Set up Python 3.13
         id: python
         uses: actions/setup-python@e797f83bcb11b83ae66e0230d6156d7c80228e7c # v6.0.0
@@ -273,7 +273,7 @@ jobs:
     if: github.event_name == 'pull_request' && (needs.determine-jobs.outputs.cpp-unit-tests-run-all == 'true' || needs.determine-jobs.outputs.cpp-unit-tests-components != '[]')
     steps:
       - name: Check out code from GitHub
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
       - name: Restore Python
         uses: ./.github/actions/restore-python
@@ -321,7 +321,7 @@ jobs:
 
     steps:
       - name: Check out code from GitHub
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
         with:
           # Need history for HEAD~1 to work for checking changed files
           fetch-depth: 2
@@ -400,7 +400,7 @@ jobs:
       GH_TOKEN: ${{ github.token }}
     steps:
       - name: Check out code from GitHub
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
         with:
           # Need history for HEAD~1 to work for checking changed files
           fetch-depth: 2
@@ -489,7 +489,7 @@ jobs:
 
     steps:
       - name: Check out code from GitHub
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
         with:
           # Need history for HEAD~1 to work for checking changed files
           fetch-depth: 2
@@ -577,7 +577,7 @@ jobs:
           version: 1.0
 
       - name: Check out code from GitHub
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - name: Restore Python
         uses: ./.github/actions/restore-python
         with:
@@ -662,7 +662,7 @@ jobs:
     if: github.event_name == 'pull_request' && !startsWith(github.base_ref, 'beta') && !startsWith(github.base_ref, 'release')
     steps:
       - name: Check out code from GitHub
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - name: Restore Python
         uses: ./.github/actions/restore-python
         with:
@@ -688,7 +688,7 @@ jobs:
       skip: ${{ steps.check-script.outputs.skip }}
     steps:
       - name: Check out target branch
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
         with:
           ref: ${{ github.base_ref }}
 
@@ -840,7 +840,7 @@ jobs:
       flash_usage: ${{ steps.extract.outputs.flash_usage }}
     steps:
       - name: Check out PR branch
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - name: Restore Python
         uses: ./.github/actions/restore-python
         with:
@@ -908,7 +908,7 @@ jobs:
       GH_TOKEN: ${{ github.token }}
     steps:
       - name: Check out code
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - name: Restore Python
         uses: ./.github/actions/restore-python
         with:
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index 21fff10c95..80fab8819a 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -54,7 +54,7 @@ jobs:
             # your codebase is analyzed, see https://docs.github.com/en/code-security/code-scanning/creating-an-advanced-setup-for-code-scanning/codeql-code-scanning-for-compiled-languages
     steps:
       - name: Checkout repository
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
       # Initializes the CodeQL tools for scanning.
       - name: Initialize CodeQL
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index a064f6ef3a..497ecd29e7 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -20,7 +20,7 @@ jobs:
       branch_build: ${{ steps.tag.outputs.branch_build }}
       deploy_env: ${{ steps.tag.outputs.deploy_env }}
     steps:
-      - uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+      - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - name: Get tag
         id: tag
         # yamllint disable rule:line-length
@@ -60,7 +60,7 @@ jobs:
       contents: read
       id-token: write
     steps:
-      - uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+      - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - name: Set up Python
         uses: actions/setup-python@e797f83bcb11b83ae66e0230d6156d7c80228e7c # v6.0.0
         with:
@@ -92,7 +92,7 @@ jobs:
             os: "ubuntu-24.04-arm"
 
     steps:
-      - uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+      - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
       - name: Set up Python
         uses: actions/setup-python@e797f83bcb11b83ae66e0230d6156d7c80228e7c # v6.0.0
         with:
@@ -168,7 +168,7 @@ jobs:
           - ghcr
           - dockerhub
     steps:
-      - uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+      - uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
       - name: Download digests
         uses: actions/download-artifact@018cc2cf5baa6db3ef3c5f8a56943fffe632ef53 # v6.0.0
diff --git a/.github/workflows/sync-device-classes.yml b/.github/workflows/sync-device-classes.yml
index 4fc287b067..2e36dc517d 100644
--- a/.github/workflows/sync-device-classes.yml
+++ b/.github/workflows/sync-device-classes.yml
@@ -13,10 +13,10 @@ jobs:
     if: github.repository == 'esphome/esphome'
     steps:
       - name: Checkout
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
 
       - name: Checkout Home Assistant
-        uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5.0.1
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6.0.0
         with:
           repository: home-assistant/core
           path: lib/home-assistant
diff --git a/CODEOWNERS b/CODEOWNERS
index 250fbbd4d4..c3d8f4350f 100644
--- a/CODEOWNERS
+++ b/CODEOWNERS
@@ -202,6 +202,7 @@ esphome/components/havells_solar/* @sourabhjaiswal
 esphome/components/hbridge/fan/* @WeekendWarrior
 esphome/components/hbridge/light/* @DotNetDann
 esphome/components/hbridge/switch/* @dwmw2
+esphome/components/hc8/* @omartijn
 esphome/components/hdc2010/* @optimusprimespace @ssieb
 esphome/components/he60r/* @clydebarrow
 esphome/components/heatpumpir/* @rob-deutsch
diff --git a/esphome/components/climate_ir/__init__.py b/esphome/components/climate_ir/__init__.py
index 6d66abf4cd..5315be3db6 100644
--- a/esphome/components/climate_ir/__init__.py
+++ b/esphome/components/climate_ir/__init__.py
@@ -3,7 +3,12 @@ import logging
 import esphome.codegen as cg
 from esphome.components import climate, remote_base, sensor
 import esphome.config_validation as cv
-from esphome.const import CONF_SENSOR, CONF_SUPPORTS_COOL, CONF_SUPPORTS_HEAT
+from esphome.const import (
+    CONF_HUMIDITY_SENSOR,
+    CONF_SENSOR,
+    CONF_SUPPORTS_COOL,
+    CONF_SUPPORTS_HEAT,
+)
 from esphome.cpp_generator import MockObjClass
 
 _LOGGER = logging.getLogger(__name__)
@@ -32,6 +37,7 @@ def climate_ir_schema(
                 cv.Optional(CONF_SUPPORTS_COOL, default=True): cv.boolean,
                 cv.Optional(CONF_SUPPORTS_HEAT, default=True): cv.boolean,
                 cv.Optional(CONF_SENSOR): cv.use_id(sensor.Sensor),
+                cv.Optional(CONF_HUMIDITY_SENSOR): cv.use_id(sensor.Sensor),
             }
         )
         .extend(cv.COMPONENT_SCHEMA)
@@ -61,6 +67,9 @@ async def register_climate_ir(var, config):
     if sensor_id := config.get(CONF_SENSOR):
         sens = await cg.get_variable(sensor_id)
         cg.add(var.set_sensor(sens))
+    if sensor_id := config.get(CONF_HUMIDITY_SENSOR):
+        sens = await cg.get_variable(sensor_id)
+        cg.add(var.set_humidity_sensor(sens))
 
 
 async def new_climate_ir(config, *args):
diff --git a/esphome/components/climate_ir/climate_ir.cpp b/esphome/components/climate_ir/climate_ir.cpp
index 2b95792a6c..50c8d459b0 100644
--- a/esphome/components/climate_ir/climate_ir.cpp
+++ b/esphome/components/climate_ir/climate_ir.cpp
@@ -11,7 +11,9 @@ climate::ClimateTraits ClimateIR::traits() {
   if (this->sensor_ != nullptr) {
     traits.add_feature_flags(climate::CLIMATE_SUPPORTS_CURRENT_TEMPERATURE);
   }
-
+  if (this->humidity_sensor_ != nullptr) {
+    traits.add_feature_flags(climate::CLIMATE_SUPPORTS_CURRENT_HUMIDITY);
+  }
   traits.set_supported_modes({climate::CLIMATE_MODE_OFF, climate::CLIMATE_MODE_HEAT_COOL});
   if (this->supports_cool_)
     traits.add_supported_mode(climate::CLIMATE_MODE_COOL);
@@ -39,9 +41,16 @@ void ClimateIR::setup() {
       this->publish_state();
     });
     this->current_temperature = this->sensor_->state;
-  } else {
-    this->current_temperature = NAN;
   }
+  if (this->humidity_sensor_ != nullptr) {
+    this->humidity_sensor_->add_on_state_callback([this](float state) {
+      this->current_humidity = state;
+      // current humidity changed, publish state
+      this->publish_state();
+    });
+    this->current_humidity = this->humidity_sensor_->state;
+  }
+
   // restore set points
   auto restore = this->restore_state_();
   if (restore.has_value()) {
diff --git a/esphome/components/climate_ir/climate_ir.h b/esphome/components/climate_ir/climate_ir.h
index 62a43f0b2d..ac76d33853 100644
--- a/esphome/components/climate_ir/climate_ir.h
+++ b/esphome/components/climate_ir/climate_ir.h
@@ -43,6 +43,7 @@ class ClimateIR : public Component,
   void set_supports_cool(bool supports_cool) { this->supports_cool_ = supports_cool; }
   void set_supports_heat(bool supports_heat) { this->supports_heat_ = supports_heat; }
   void set_sensor(sensor::Sensor *sensor) { this->sensor_ = sensor; }
+  void set_humidity_sensor(sensor::Sensor *sensor) { this->humidity_sensor_ = sensor; }
 
  protected:
   float minimum_temperature_, maximum_temperature_, temperature_step_;
@@ -67,6 +68,7 @@ class ClimateIR : public Component,
   climate::ClimatePresetMask presets_{};
 
   sensor::Sensor *sensor_{nullptr};
+  sensor::Sensor *humidity_sensor_{nullptr};
 };
 
 }  // namespace climate_ir
diff --git a/esphome/components/cst816/touchscreen/cst816_touchscreen.cpp b/esphome/components/cst816/touchscreen/cst816_touchscreen.cpp
index 0ba2d9df94..8ed9fa3f87 100644
--- a/esphome/components/cst816/touchscreen/cst816_touchscreen.cpp
+++ b/esphome/components/cst816/touchscreen/cst816_touchscreen.cpp
@@ -19,8 +19,8 @@ void CST816Touchscreen::continue_setup_() {
       case CST816T_CHIP_ID:
         break;
       default:
-        this->mark_failed();
         this->status_set_error(str_sprintf("Unknown chip ID 0x%02X", this->chip_id_).c_str());
+        this->mark_failed();
         return;
     }
     this->write_byte(REG_IRQ_CTL, IRQ_EN_MOTION);
diff --git a/esphome/components/esp32/gpio.cpp b/esphome/components/esp32/gpio.cpp
index a98245b889..392499836c 100644
--- a/esphome/components/esp32/gpio.cpp
+++ b/esphome/components/esp32/gpio.cpp
@@ -85,7 +85,6 @@ void ESP32InternalGPIOPin::attach_interrupt(void (*func)(void *), void *arg, gpi
       break;
   }
   gpio_set_intr_type(this->get_pin_num(), idf_type);
-  gpio_intr_enable(this->get_pin_num());
   if (!isr_service_installed) {
     auto res = gpio_install_isr_service(ESP_INTR_FLAG_LEVEL3);
     if (res != ESP_OK) {
diff --git a/esphome/components/hc8/__init__.py b/esphome/components/hc8/__init__.py
new file mode 100644
index 0000000000..e1028456b0
--- /dev/null
+++ b/esphome/components/hc8/__init__.py
@@ -0,0 +1 @@
+CODEOWNERS = ["@omartijn"]
diff --git a/esphome/components/hc8/hc8.cpp b/esphome/components/hc8/hc8.cpp
new file mode 100644
index 0000000000..5b649c2735
--- /dev/null
+++ b/esphome/components/hc8/hc8.cpp
@@ -0,0 +1,99 @@
+#include "hc8.h"
+#include "esphome/core/application.h"
+#include "esphome/core/helpers.h"
+#include "esphome/core/log.h"
+
+#include <array>
+
+namespace esphome::hc8 {
+
+static const char *const TAG = "hc8";
+static const std::array<uint8_t, 5> HC8_COMMAND_GET_PPM{0x64, 0x69, 0x03, 0x5E, 0x4E};
+static const std::array<uint8_t, 3> HC8_COMMAND_CALIBRATE_PREAMBLE{0x11, 0x03, 0x03};
+
+void HC8Component::setup() {
+  // send an initial query to the device, this will
+  // get it out of "active output mode", where it
+  // generates data every second
+  this->write_array(HC8_COMMAND_GET_PPM);
+  this->flush();
+
+  // ensure the buffer is empty
+  while (this->available())
+    this->read();
+}
+
+void HC8Component::update() {
+  uint32_t now_ms = App.get_loop_component_start_time();
+  uint32_t warmup_ms = this->warmup_seconds_ * 1000;
+  if (now_ms < warmup_ms) {
+    ESP_LOGW(TAG, "HC8 warming up, %" PRIu32 " s left", (warmup_ms - now_ms) / 1000);
+    this->status_set_warning();
+    return;
+  }
+
+  while (this->available())
+    this->read();
+
+  this->write_array(HC8_COMMAND_GET_PPM);
+  this->flush();
+
+  // the sensor is a bit slow in responding, so trying to
+  // read immediately after sending a query will timeout
+  this->set_timeout(50, [this]() {
+    std::array<uint8_t, 14> response;
+    if (!this->read_array(response.data(), response.size())) {
+      ESP_LOGW(TAG, "Reading data from HC8 failed!");
+      this->status_set_warning();
+      return;
+    }
+
+    if (response[0] != 0x64 || response[1] != 0x69) {
+      ESP_LOGW(TAG, "Invalid preamble from HC8!");
+      this->status_set_warning();
+      return;
+    }
+
+    if (crc16(response.data(), 12) != encode_uint16(response[13], response[12])) {
+      ESP_LOGW(TAG, "HC8 Checksum mismatch");
+      this->status_set_warning();
+      return;
+    }
+
+    this->status_clear_warning();
+
+    const uint16_t ppm = encode_uint16(response[5], response[4]);
+    ESP_LOGD(TAG, "HC8 Received CO₂=%uppm", ppm);
+    if (this->co2_sensor_ != nullptr)
+      this->co2_sensor_->publish_state(ppm);
+  });
+}
+
+void HC8Component::calibrate(uint16_t baseline) {
+  ESP_LOGD(TAG, "HC8 Calibrating baseline to %uppm", baseline);
+
+  std::array<uint8_t, 6> command{};
+  std::copy(begin(HC8_COMMAND_CALIBRATE_PREAMBLE), end(HC8_COMMAND_CALIBRATE_PREAMBLE), begin(command));
+  command[3] = baseline >> 8;
+  command[4] = baseline;
+  command[5] = 0;
+
+  // the last byte is a checksum over the data
+  for (uint8_t i = 0; i < 5; ++i)
+    command[5] -= command[i];
+
+  this->write_array(command);
+  this->flush();
+}
+
+float HC8Component::get_setup_priority() const { return setup_priority::DATA; }
+
+void HC8Component::dump_config() {
+  ESP_LOGCONFIG(TAG, "HC8:");
+  LOG_SENSOR("  ", "CO2", this->co2_sensor_);
+  this->check_uart_settings(9600);
+
+  ESP_LOGCONFIG(TAG, "  Warmup time: %" PRIu32 " s", this->warmup_seconds_);
+}
+
+}  // namespace esphome::hc8
diff --git a/esphome/components/hc8/hc8.h b/esphome/components/hc8/hc8.h
new file mode 100644
index 0000000000..7711fb8c97
--- /dev/null
+++ b/esphome/components/hc8/hc8.h
@@ -0,0 +1,37 @@
+#pragma once
+
+#include "esphome/core/component.h"
+#include "esphome/core/automation.h"
+#include "esphome/components/sensor/sensor.h"
+#include "esphome/components/uart/uart.h"
+
+#include <cinttypes>
+
+namespace esphome::hc8 {
+
+class HC8Component : public PollingComponent, public uart::UARTDevice {
+ public:
+  float get_setup_priority() const override;
+
+  void setup() override;
+  void update() override;
+  void dump_config() override;
+
+  void calibrate(uint16_t baseline);
+
+  void set_co2_sensor(sensor::Sensor *co2_sensor) { co2_sensor_ = co2_sensor; }
+  void set_warmup_seconds(uint32_t seconds) { warmup_seconds_ = seconds; }
+
+ protected:
+  sensor::Sensor *co2_sensor_{nullptr};
+  uint32_t warmup_seconds_{0};
+};
+
+template<typename... Ts> class HC8CalibrateAction : public Action<Ts...>, public Parented<HC8Component> {
+ public:
+  TEMPLATABLE_VALUE(uint16_t, baseline)
+
+  void play(const Ts &...x) override { this->parent_->calibrate(this->baseline_.value(x...)); }
+};
+
+}  // namespace esphome::hc8
diff --git a/esphome/components/hc8/sensor.py b/esphome/components/hc8/sensor.py
new file mode 100644
index 0000000000..90698b2661
--- /dev/null
+++ b/esphome/components/hc8/sensor.py
@@ -0,0 +1,79 @@
+from esphome import automation
+import esphome.codegen as cg
+from esphome.components import sensor, uart
+import esphome.config_validation as cv
+from esphome.const import (
+    CONF_BASELINE,
+    CONF_CO2,
+    CONF_ID,
+    DEVICE_CLASS_CARBON_DIOXIDE,
+    ICON_MOLECULE_CO2,
+    STATE_CLASS_MEASUREMENT,
+    UNIT_PARTS_PER_MILLION,
+)
+
+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)
+
+CONFIG_SCHEMA = (
+    cv.Schema(
+        {
+            cv.GenerateID(): cv.declare_id(HC8Component),
+            cv.Optional(CONF_CO2): sensor.sensor_schema(
+                unit_of_measurement=UNIT_PARTS_PER_MILLION,
+                icon=ICON_MOLECULE_CO2,
+                accuracy_decimals=0,
+                device_class=DEVICE_CLASS_CARBON_DIOXIDE,
+                state_class=STATE_CLASS_MEASUREMENT,
+            ),
+            cv.Optional(
+                CONF_WARMUP_TIME, default="75s"
+            ): cv.positive_time_period_seconds,
+        }
+    )
+    .extend(cv.polling_component_schema("60s"))
+    .extend(uart.UART_DEVICE_SCHEMA)
+)
+
+FINAL_VALIDATE_SCHEMA = uart.final_validate_device_schema(
+    "hc8",
+    baud_rate=9600,
+    require_rx=True,
+    require_tx=True,
+)
+
+
+async def to_code(config):
+    var = cg.new_Pvariable(config[CONF_ID])
+    await cg.register_component(var, config)
+    await uart.register_uart_device(var, config)
+
+    if co2 := config.get(CONF_CO2):
+        sens = await sensor.new_sensor(co2)
+        cg.add(var.set_co2_sensor(sens))
+
+    cg.add(var.set_warmup_seconds(config[CONF_WARMUP_TIME]))
+
+
+CALIBRATION_ACTION_SCHEMA = cv.Schema(
+    {
+        cv.Required(CONF_ID): cv.use_id(HC8Component),
+        cv.Required(CONF_BASELINE): cv.templatable(cv.uint16_t),
+    }
+)
+
+
+@automation.register_action(
+    "hc8.calibrate", HC8CalibrateAction, CALIBRATION_ACTION_SCHEMA
+)
+async def hc8_calibration_to_code(config, action_id, template_arg, args):
+    var = cg.new_Pvariable(action_id, template_arg)
+    await cg.register_parented(var, config[CONF_ID])
+    template_ = await cg.templatable(config[CONF_BASELINE], args, cg.uint16)
+    cg.add(var.set_baseline(template_))
+    return var
diff --git a/esphome/components/i2c/i2c_bus_zephyr.cpp b/esphome/components/i2c/i2c_bus_zephyr.cpp
index 658dcee35c..1eb9944dcb 100644
--- a/esphome/components/i2c/i2c_bus_zephyr.cpp
+++ b/esphome/components/i2c/i2c_bus_zephyr.cpp
@@ -8,6 +8,22 @@ namespace esphome::i2c {
 
 static const char *const TAG = "i2c.zephyr";
 
+static const char *get_speed(uint32_t dev_config) {
+  switch (I2C_SPEED_GET(dev_config)) {
+    case I2C_SPEED_STANDARD:
+      return "100 kHz";
+    case I2C_SPEED_FAST:
+      return "400 kHz";
+    case I2C_SPEED_FAST_PLUS:
+      return "1 MHz";
+    case I2C_SPEED_HIGH:
+      return "3.4 MHz";
+    case I2C_SPEED_ULTRA:
+      return "5 MHz";
+  }
+  return "unknown";
+}
+
 void ZephyrI2CBus::setup() {
   if (!device_is_ready(this->i2c_dev_)) {
     ESP_LOGE(TAG, "I2C dev is not ready.");
@@ -31,21 +47,6 @@ void ZephyrI2CBus::setup() {
 }
 
 void ZephyrI2CBus::dump_config() {
-  auto get_speed = [](uint32_t dev_config) {
-    switch (I2C_SPEED_GET(dev_config)) {
-      case I2C_SPEED_STANDARD:
-        return "100 kHz";
-      case I2C_SPEED_FAST:
-        return "400 kHz";
-      case I2C_SPEED_FAST_PLUS:
-        return "1 MHz";
-      case I2C_SPEED_HIGH:
-        return "3.4 MHz";
-      case I2C_SPEED_ULTRA:
-        return "5 MHz";
-    }
-    return "unknown";
-  };
   ESP_LOGCONFIG(TAG,
                 "I2C Bus:\n"
                 "  SDA Pin: GPIO%u\n"
diff --git a/esphome/components/libretiny/__init__.py b/esphome/components/libretiny/__init__.py
index c63d6d7faa..93b66888da 100644
--- a/esphome/components/libretiny/__init__.py
+++ b/esphome/components/libretiny/__init__.py
@@ -261,6 +261,10 @@ async def component_to_code(config):
     cg.add_build_flag(f"-DUSE_LIBRETINY_VARIANT_{config[CONF_FAMILY]}")
     cg.add_define("ESPHOME_BOARD", config[CONF_BOARD])
     cg.add_define("ESPHOME_VARIANT", FAMILY_FRIENDLY[config[CONF_FAMILY]])
+    # LibreTiny uses MULTI_NO_ATOMICS because platforms like BK7231N (ARM968E-S) lack
+    # exclusive load/store (no LDREX/STREX). std::atomic RMW operations require libatomic,
+    # which is not linked to save flash (4-8KB). Even if linked, libatomic would use locks
+    # (ATOMIC_INT_LOCK_FREE=1), so explicit FreeRTOS mutexes are simpler and equivalent.
     cg.add_define(ThreadModel.MULTI_NO_ATOMICS)
 
     # force using arduino framework
diff --git a/esphome/components/ltr501/ltr501.cpp b/esphome/components/ltr501/ltr501.cpp
index be5a4ddccf..04de91e362 100644
--- a/esphome/components/ltr501/ltr501.cpp
+++ b/esphome/components/ltr501/ltr501.cpp
@@ -174,7 +174,7 @@ void LTRAlsPs501Component::loop() {
       break;
 
     case State::WAITING_FOR_DATA:
-      if (this->is_als_data_ready_(this->als_readings_) == DataAvail::DATA_OK) {
+      if (this->is_als_data_ready_(this->als_readings_) == LtrDataAvail::LTR_DATA_OK) {
         tries = 0;
         ESP_LOGV(TAG, "Reading sensor data assuming gain = %.0fx, time = %d ms",
                  get_gain_coeff(this->als_readings_.gain), get_itime_ms(this->als_readings_.integration_time));
@@ -379,18 +379,18 @@ void LTRAlsPs501Component::configure_integration_time_(IntegrationTime501 time)
   }
 }
 
-DataAvail LTRAlsPs501Component::is_als_data_ready_(AlsReadings &data) {
+LtrDataAvail LTRAlsPs501Component::is_als_data_ready_(AlsReadings &data) {
   AlsPsStatusRegister als_status{0};
   als_status.raw = this->reg((uint8_t) CommandRegisters::ALS_PS_STATUS).get();
   if (!als_status.als_new_data)
-    return DataAvail::NO_DATA;
+    return LtrDataAvail::LTR_NO_DATA;
   ESP_LOGV(TAG, "Data ready, reported gain is %.0fx", get_gain_coeff(als_status.gain));
   if (data.gain != als_status.gain) {
     ESP_LOGW(TAG, "Actual gain differs from requested (%.0f)", get_gain_coeff(data.gain));
-    return DataAvail::BAD_DATA;
+    return LtrDataAvail::LTR_BAD_DATA;
   }
   data.gain = als_status.gain;
-  return DataAvail::DATA_OK;
+  return LtrDataAvail::LTR_DATA_OK;
 }
 
 void LTRAlsPs501Component::read_sensor_data_(AlsReadings &data) {
diff --git a/esphome/components/ltr501/ltr501.h b/esphome/components/ltr501/ltr501.h
index 849ff6bc23..02c025da30 100644
--- a/esphome/components/ltr501/ltr501.h
+++ b/esphome/components/ltr501/ltr501.h
@@ -11,7 +11,7 @@
 namespace esphome {
 namespace ltr501 {
 
-enum DataAvail : uint8_t { NO_DATA, BAD_DATA, DATA_OK };
+enum LtrDataAvail : uint8_t { LTR_NO_DATA, LTR_BAD_DATA, LTR_DATA_OK };
 
 enum LtrType : uint8_t {
   LTR_TYPE_UNKNOWN = 0,
@@ -106,7 +106,7 @@ class LTRAlsPs501Component : public PollingComponent, public i2c::I2CDevice {
   void configure_als_();
   void configure_integration_time_(IntegrationTime501 time);
   void configure_gain_(AlsGain501 gain);
-  DataAvail is_als_data_ready_(AlsReadings &data);
+  LtrDataAvail is_als_data_ready_(AlsReadings &data);
   void read_sensor_data_(AlsReadings &data);
   bool are_adjustments_required_(AlsReadings &data);
   void apply_lux_calculation_(AlsReadings &data);
diff --git a/esphome/components/ltr_als_ps/ltr_als_ps.cpp b/esphome/components/ltr_als_ps/ltr_als_ps.cpp
index c3ea5848c8..f9c1474c85 100644
--- a/esphome/components/ltr_als_ps/ltr_als_ps.cpp
+++ b/esphome/components/ltr_als_ps/ltr_als_ps.cpp
@@ -165,7 +165,7 @@ void LTRAlsPsComponent::loop() {
       break;
 
     case State::WAITING_FOR_DATA:
-      if (this->is_als_data_ready_(this->als_readings_) == DataAvail::DATA_OK) {
+      if (this->is_als_data_ready_(this->als_readings_) == LtrDataAvail::LTR_DATA_OK) {
         tries = 0;
         ESP_LOGV(TAG, "Reading sensor data having gain = %.0fx, time = %d ms", get_gain_coeff(this->als_readings_.gain),
                  get_itime_ms(this->als_readings_.integration_time));
@@ -376,23 +376,23 @@ void LTRAlsPsComponent::configure_integration_time_(IntegrationTime time) {
   }
 }
 
-DataAvail LTRAlsPsComponent::is_als_data_ready_(AlsReadings &data) {
+LtrDataAvail LTRAlsPsComponent::is_als_data_ready_(AlsReadings &data) {
   AlsPsStatusRegister als_status{0};
 
   als_status.raw = this->reg((uint8_t) CommandRegisters::ALS_PS_STATUS).get();
   if (!als_status.als_new_data)
-    return DataAvail::NO_DATA;
+    return LtrDataAvail::LTR_NO_DATA;
 
   if (als_status.data_invalid) {
     ESP_LOGW(TAG, "Data available but not valid");
-    return DataAvail::BAD_DATA;
+    return LtrDataAvail::LTR_BAD_DATA;
   }
   ESP_LOGV(TAG, "Data ready, reported gain is %.0f", get_gain_coeff(als_status.gain));
   if (data.gain != als_status.gain) {
     ESP_LOGW(TAG, "Actual gain differs from requested (%.0f)", get_gain_coeff(data.gain));
-    return DataAvail::BAD_DATA;
+    return LtrDataAvail::LTR_BAD_DATA;
   }
-  return DataAvail::DATA_OK;
+  return LtrDataAvail::LTR_DATA_OK;
 }
 
 void LTRAlsPsComponent::read_sensor_data_(AlsReadings &data) {
diff --git a/esphome/components/ltr_als_ps/ltr_als_ps.h b/esphome/components/ltr_als_ps/ltr_als_ps.h
index 2c768009ab..c6052300de 100644
--- a/esphome/components/ltr_als_ps/ltr_als_ps.h
+++ b/esphome/components/ltr_als_ps/ltr_als_ps.h
@@ -11,7 +11,7 @@
 namespace esphome {
 namespace ltr_als_ps {
 
-enum DataAvail : uint8_t { NO_DATA, BAD_DATA, DATA_OK };
+enum LtrDataAvail : uint8_t { LTR_NO_DATA, LTR_BAD_DATA, LTR_DATA_OK };
 
 enum LtrType : uint8_t {
   LTR_TYPE_UNKNOWN = 0,
@@ -106,7 +106,7 @@ class LTRAlsPsComponent : public PollingComponent, public i2c::I2CDevice {
   void configure_als_();
   void configure_integration_time_(IntegrationTime time);
   void configure_gain_(AlsGain gain);
-  DataAvail is_als_data_ready_(AlsReadings &data);
+  LtrDataAvail is_als_data_ready_(AlsReadings &data);
   void read_sensor_data_(AlsReadings &data);
   bool are_adjustments_required_(AlsReadings &data);
   void apply_lux_calculation_(AlsReadings &data);
diff --git a/esphome/components/mipi_rgb/models/st7701s.py b/esphome/components/mipi_rgb/models/st7701s.py
index bfd1c9aa3f..0b0a9548ca 100644
--- a/esphome/components/mipi_rgb/models/st7701s.py
+++ b/esphome/components/mipi_rgb/models/st7701s.py
@@ -24,6 +24,8 @@ class ST7701S(DriverChip):
         sdir = 0
         if transform.get(CONF_MIRROR_X):
             sdir |= 0x04
+            # XFLIP doesn't do anything in the ST7701S,
+            # it's set in the madctl byte just so it can be reported at runtime by logconfig
             madctl |= MADCTL_XFLIP
         sequence.append((SDIR_CMD, sdir))
         return madctl
diff --git a/esphome/components/packet_transport/packet_transport.cpp b/esphome/components/packet_transport/packet_transport.cpp
index 8bde4ee505..857b40ca0e 100644
--- a/esphome/components/packet_transport/packet_transport.cpp
+++ b/esphome/components/packet_transport/packet_transport.cpp
@@ -195,8 +195,8 @@ static void add(std::vector<uint8_t> &vec, const char *str) {
 void PacketTransport::setup() {
   this->name_ = App.get_name().c_str();
   if (strlen(this->name_) > 255) {
-    this->mark_failed();
     this->status_set_error("Device name exceeds 255 chars");
+    this->mark_failed();
     return;
   }
   this->resend_ping_key_ = this->ping_pong_enable_;
diff --git a/esphome/components/udp/udp_component.cpp b/esphome/components/udp/udp_component.cpp
index 8a9ce612b4..7714793e1c 100644
--- a/esphome/components/udp/udp_component.cpp
+++ b/esphome/components/udp/udp_component.cpp
@@ -21,8 +21,8 @@ void UDPComponent::setup() {
   if (this->should_broadcast_) {
     this->broadcast_socket_ = socket::socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
     if (this->broadcast_socket_ == nullptr) {
-      this->mark_failed();
       this->status_set_error("Could not create socket");
+      this->mark_failed();
       return;
     }
     int enable = 1;
@@ -41,15 +41,15 @@ void UDPComponent::setup() {
   if (this->should_listen_) {
     this->listen_socket_ = socket::socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
     if (this->listen_socket_ == nullptr) {
-      this->mark_failed();
       this->status_set_error("Could not create socket");
+      this->mark_failed();
       return;
     }
     auto err = this->listen_socket_->setblocking(false);
     if (err < 0) {
       ESP_LOGE(TAG, "Unable to set nonblocking: errno %d", errno);
-      this->mark_failed();
       this->status_set_error("Unable to set nonblocking");
+      this->mark_failed();
       return;
     }
     int enable = 1;
@@ -73,8 +73,8 @@ void UDPComponent::setup() {
       err = this->listen_socket_->setsockopt(IPPROTO_IP, IP_ADD_MEMBERSHIP, &imreq, sizeof(imreq));
       if (err < 0) {
         ESP_LOGE(TAG, "Failed to set IP_ADD_MEMBERSHIP. Error %d", errno);
-        this->mark_failed();
         this->status_set_error("Failed to set IP_ADD_MEMBERSHIP");
+        this->mark_failed();
         return;
       }
     }
@@ -82,8 +82,8 @@ void UDPComponent::setup() {
     err = this->listen_socket_->bind((struct sockaddr *) &server, sizeof(server));
     if (err != 0) {
       ESP_LOGE(TAG, "Socket unable to bind: errno %d", errno);
-      this->mark_failed();
       this->status_set_error("Unable to bind socket");
+      this->mark_failed();
       return;
     }
   }
diff --git a/esphome/components/wake_on_lan/wake_on_lan.cpp b/esphome/components/wake_on_lan/wake_on_lan.cpp
index adf5a080e5..7993abd7e7 100644
--- a/esphome/components/wake_on_lan/wake_on_lan.cpp
+++ b/esphome/components/wake_on_lan/wake_on_lan.cpp
@@ -67,8 +67,8 @@ void WakeOnLanButton::setup() {
 #if defined(USE_SOCKET_IMPL_BSD_SOCKETS) || defined(USE_SOCKET_IMPL_LWIP_SOCKETS)
   this->broadcast_socket_ = socket::socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
   if (this->broadcast_socket_ == nullptr) {
-    this->mark_failed();
     this->status_set_error("Could not create socket");
+    this->mark_failed();
     return;
   }
   int enable = 1;
diff --git a/esphome/const.py b/esphome/const.py
index b4cd3cfd1c..2b6b60d395 100644
--- a/esphome/const.py
+++ b/esphome/const.py
@@ -36,7 +36,30 @@ class Framework(StrEnum):
 
 
 class ThreadModel(StrEnum):
-    """Threading model identifiers for ESPHome scheduler."""
+    """Threading model identifiers for ESPHome scheduler.
+
+    ESPHome currently uses three threading models based on platform capabilities:
+
+    SINGLE:
+        - Single-threaded platforms (ESP8266, RP2040)
+        - No RTOS task switching
+        - No concurrent access to scheduler data structures
+        - No atomics or locks required
+        - Minimal overhead
+
+    MULTI_NO_ATOMICS:
+        - Multi-threaded platforms without hardware atomic RMW support (e.g. LibreTiny BK7231N)
+        - Uses FreeRTOS or another RTOS with multiple tasks
+        - CPU lacks exclusive load/store instructions (ARM968E-S has no LDREX/STREX)
+        - std::atomic cannot provide lock-free RMW; libatomic is avoided to save flash (4–8 KB)
+        - Scheduler uses explicit FreeRTOS mutexes for synchronization
+
+    MULTI_ATOMICS:
+        - Multi-threaded platforms with hardware atomic RMW support (ESP32, Cortex-M, Host)
+        - CPU provides native atomic instructions (ESP32 S32C1I, ARM LDREX/STREX)
+        - std::atomic is used for lock-free synchronization
+        - Reduced contention and better performance
+    """
 
     SINGLE = "ESPHOME_THREAD_SINGLE"
     MULTI_NO_ATOMICS = "ESPHOME_THREAD_MULTI_NO_ATOMICS"
diff --git a/tests/components/climate_ir_lg/common.yaml b/tests/components/climate_ir_lg/common.yaml
index da0d656b21..37011b16ee 100644
--- a/tests/components/climate_ir_lg/common.yaml
+++ b/tests/components/climate_ir_lg/common.yaml
@@ -1,4 +1,16 @@
+sensor:
+  - platform: template
+    id: temp_sensor
+    lambda: return 22.0;
+    update_interval: 60s
+  - platform: template
+    id: humidity_sensor
+    lambda: return 50.0;
+    update_interval: 60s
+
 climate:
   - platform: climate_ir_lg
     name: LG Climate
     transmitter_id: xmitr
+    sensor: temp_sensor
+    humidity_sensor: humidity_sensor
diff --git a/tests/components/hc8/common.yaml b/tests/components/hc8/common.yaml
new file mode 100644
index 0000000000..ac3b454315
--- /dev/null
+++ b/tests/components/hc8/common.yaml
@@ -0,0 +1,13 @@
+esphome:
+  on_boot:
+    then:
+      - hc8.calibrate:
+          id: hc8_sensor
+          baseline: 420
+
+sensor:
+  - platform: hc8
+    id: hc8_sensor
+    co2:
+      name: HC8 CO2 Value
+    update_interval: 15s
diff --git a/tests/components/hc8/test.esp32-idf.yaml b/tests/components/hc8/test.esp32-idf.yaml
new file mode 100644
index 0000000000..2d29656c94
--- /dev/null
+++ b/tests/components/hc8/test.esp32-idf.yaml
@@ -0,0 +1,4 @@
+packages:
+  uart: !include ../../test_build_components/common/uart/esp32-idf.yaml
+
+<<: !include common.yaml
diff --git a/tests/components/hc8/test.esp8266-ard.yaml b/tests/components/hc8/test.esp8266-ard.yaml
new file mode 100644
index 0000000000..5a05efa259
--- /dev/null
+++ b/tests/components/hc8/test.esp8266-ard.yaml
@@ -0,0 +1,4 @@
+packages:
+  uart: !include ../../test_build_components/common/uart/esp8266-ard.yaml
+
+<<: !include common.yaml
diff --git a/tests/components/hc8/test.rp2040-ard.yaml b/tests/components/hc8/test.rp2040-ard.yaml
new file mode 100644
index 0000000000..f1df2daf83
--- /dev/null
+++ b/tests/components/hc8/test.rp2040-ard.yaml
@@ -0,0 +1,4 @@
+packages:
+  uart: !include ../../test_build_components/common/uart/rp2040-ard.yaml
+
+<<: !include common.yaml