[openthread] fix shutdown (#16332)

Co-authored-by: pre-commit-ci-lite[bot] <117423508+pre-commit-ci-lite[bot]@users.noreply.github.com>
Co-authored-by: Jonathan Swoboda <154711427+swoboda1337@users.noreply.github.com>
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

esphome/components/openthread/openthread.cpp

@@ -4,6 +4,7 @@
 
 #include <openthread/cli.h>
 #include <openthread/instance.h>
+#include <openthread/ip6.h>
 #include <openthread/logging.h>
 #include <openthread/netdata.h>
 #include <openthread/tasklet.h>
@@ -229,26 +230,43 @@ void *OpenThreadSrpComponent::pool_alloc_(size_t size) {
 void OpenThreadSrpComponent::set_mdns(esphome::mdns::MDNSComponent *mdns) { this->mdns_ = mdns; }
 
 bool OpenThreadComponent::teardown() {
-  if (!this->teardown_started_) {
-    this->teardown_started_ = true;
-    ESP_LOGD(TAG, "Clear Srp");
-    auto lock = InstanceLock::try_acquire(100);
-    if (!lock) {
-      ESP_LOGW(TAG, "Failed to acquire OpenThread lock during teardown, leaking memory");
-      return true;
-    }
-    otInstance *instance = lock.get_instance();
-    otSrpClientClearHostAndServices(instance);
-    otSrpClientBuffersFreeAllServices(instance);
-    global_openthread_component = nullptr;
-    ESP_LOGD(TAG, "Exit main loop ");
-    int error = this->openthread_stop_();
-    if (error != 0) {
-      ESP_LOGW(TAG, "Failed attempt to stop main loop %d", error);
-      this->teardown_complete_ = true;
-    }
+  switch (this->teardown_stage_) {
+    case TeardownStage::TEARDOWN_STAGE_NOT_STARTED: {
+      auto lock = InstanceLock::try_acquire(100);
+      if (!lock) {
+        // Try again on next teardown loop
+        ESP_LOGV(TAG, "Failed to acquire OpenThread lock during teardown");
+        return false;
+      }
+      // Start tearing down
+      this->teardown_stage_ = TeardownStage::TEARDOWN_STAGE_STOP_IN_PROCESS;
+      ESP_LOGV(TAG, "Clear SRP");
+      otInstance *instance = lock.get_instance();
+      otSrpClientClearHostAndServices(instance);
+      otSrpClientBuffersFreeAllServices(instance);
+      if (otThreadSetEnabled(instance, false) != OT_ERROR_NONE) {
+        ESP_LOGW(TAG, "Failed to disable Thread during teardown");
+      }
+      if (otIp6SetEnabled(instance, false) != OT_ERROR_NONE) {
+        ESP_LOGW(TAG, "Failed to disable IPv6 during teardown");
+      }
+      // Stop OpenThread
+      global_openthread_component = nullptr;
+      ESP_LOGV(TAG, "Stop OpenThread");
+      int error = this->openthread_stop_();
+      if (error != 0) {
+        ESP_LOGW(TAG, "Failed attempt to stop OpenThread %d", error);
+        this->teardown_stage_ = TeardownStage::TEARDOWN_STAGE_COMPLETED;
+      }
+    } break;
+    case TeardownStage::TEARDOWN_STAGE_STOP_IN_PROCESS:
+      // Waiting on OpenThread stop
+      break;
+    case TeardownStage::TEARDOWN_STAGE_COMPLETED:
+      ESP_LOGV(TAG, "OpenThreadComponent Teardown Complete");
+      break;
   }
-  return this->teardown_complete_;
+  return this->teardown_stage_ == TeardownStage::TEARDOWN_STAGE_COMPLETED;
 }
 
 void OpenThreadComponent::on_factory_reset(std::function<void()> callback) {

esphome/components/openthread/openthread.h

@@ -19,6 +19,12 @@ namespace esphome::openthread {
 
 class InstanceLock;
 
+enum class TeardownStage : uint8_t {
+  TEARDOWN_STAGE_NOT_STARTED = 0,
+  TEARDOWN_STAGE_STOP_IN_PROCESS,
+  TEARDOWN_STAGE_COMPLETED,
+};
+
 template<typename... Ts> class OpenThreadComponentPollPeriodAction;
 
 class OpenThreadComponent final : public Component {
@@ -71,9 +77,8 @@ class OpenThreadComponent final : public Component {
 #endif
   std::optional<int8_t> output_power_{};
   std::atomic<bool> lock_initialized_{false};
-  bool teardown_started_{false};
-  bool teardown_complete_{false};
-  bool connected_{false};
+  std::atomic<TeardownStage> teardown_stage_{TeardownStage::TEARDOWN_STAGE_NOT_STARTED};
+  std::atomic<bool> connected_{false};
 
  private:
   // Stores a pointer to a string literal (static storage duration).

esphome/components/openthread/openthread_esp.cpp

@@ -168,7 +168,7 @@ void OpenThreadComponent::ot_main() {
   esp_netif_destroy(openthread_netif);
 
   esp_vfs_eventfd_unregister();
-  this->teardown_complete_ = true;
+  this->teardown_stage_ = TeardownStage::TEARDOWN_STAGE_COMPLETED;
   vTaskDelete(NULL);
 }
 

esphome/components/openthread/openthread_zephyr.cpp

@@ -90,10 +90,8 @@ void OpenThreadComponent::ot_main() {}
 otInstance *OpenThreadComponent::get_openthread_instance_() { return openthread_get_default_instance(); }
 
 int OpenThreadComponent::openthread_stop_() {
-  // OT stack is intentionally left running — no Zephyr stop API. The state callback stays
-  // registered but is safe (null-checks global_openthread_component). nRF52840 never
-  // re-enters setup() after teardown so this is functionally correct.
-  this->teardown_complete_ = true;
+  // Zephyr has no stack-stop API, so stop is synchronous here; mark complete immediately.
+  this->teardown_stage_ = TeardownStage::TEARDOWN_STAGE_COMPLETED;
   return 0;
 }