From d5ad9dc0fb41beed00580ae6c02d0510d2bb8f9c Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@home-assistant.io>
Date: Tue, 23 Sep 2025 21:58:01 -0500
Subject: [PATCH] fix

---
 .../components/usb_host/usb_host_client.cpp   | 19 ++++++++++---------
 esphome/components/usb_uart/usb_uart.cpp      |  5 ++---
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/esphome/components/usb_host/usb_host_client.cpp b/esphome/components/usb_host/usb_host_client.cpp
index d294520568..1abc260bbf 100644
--- a/esphome/components/usb_host/usb_host_client.cpp
+++ b/esphome/components/usb_host/usb_host_client.cpp
@@ -307,6 +307,14 @@ void USBClient::on_removed(usb_device_handle_t handle) {
   }
 }
 
+// Helper to queue transfer cleanup to main loop
+static void queue_transfer_cleanup(TransferRequest *trq, EventType type) {
+  UsbEvent event;
+  event.type = type;
+  event.data.transfer.trq = trq;
+  xQueueSend(trq->client->get_event_queue(), &event, portMAX_DELAY);
+}
+
 // CALLBACK CONTEXT: USB task (called from usb_host_client_handle_events in USB task)
 static void control_callback(const usb_transfer_t *xfer) {
   auto *trq = static_cast<TransferRequest *>(xfer->context);
@@ -322,10 +330,7 @@ static void control_callback(const usb_transfer_t *xfer) {
   }
 
   // Queue cleanup to main loop
-  UsbEvent event;
-  event.type = EVENT_CONTROL_COMPLETE;
-  event.data.transfer.trq = trq;
-  xQueueSend(trq->client->get_event_queue(), &event, portMAX_DELAY);
+  queue_transfer_cleanup(trq, EVENT_CONTROL_COMPLETE);
 }
 
 TransferRequest *USBClient::get_trq_() {
@@ -402,11 +407,7 @@ static void transfer_callback(usb_transfer_t *xfer) {
   }
 
   // Queue cleanup to main loop
-  UsbEvent event;
-  event.type = EVENT_TRANSFER_COMPLETE;
-  event.data.transfer.trq = trq;
-  event.data.transfer.callback_executed = true;
-  xQueueSend(trq->client->get_event_queue(), &event, portMAX_DELAY);
+  queue_transfer_cleanup(trq, EVENT_TRANSFER_COMPLETE);
 }
 /**
  * Performs a transfer input operation.
diff --git a/esphome/components/usb_uart/usb_uart.cpp b/esphome/components/usb_uart/usb_uart.cpp
index b485397214..5aa9f65f12 100644
--- a/esphome/components/usb_uart/usb_uart.cpp
+++ b/esphome/components/usb_uart/usb_uart.cpp
@@ -266,12 +266,11 @@ void USBUartComponent::start_output(USBUartChannel *channel) {
     return;
   }
   const auto *ep = channel->cdc_dev_.out_ep;
-  // CALLBACK CONTEXT: This lambda is stored in TransferRequest and will be executed
-  // in MAIN LOOP after being queued by transfer_callback in USB task
+  // CALLBACK CONTEXT: This lambda is executed in USB task via transfer_callback
   auto callback = [this, channel](const usb_host::TransferStatus &status) {
     ESP_LOGV(TAG, "Output Transfer result: length: %u; status %X", status.data_len, status.error_code);
     channel->output_started_ = false;
-    // DEFERRED CONTEXT: Main loop (restart output in main loop)
+    // Defer restart to main loop (defer is thread-safe)
     this->defer([this, channel] { this->start_output(channel); });
   };
   channel->output_started_ = true;