diff --git a/src/osal/osal_freertos.h b/src/osal/osal_freertos.h
new file mode 100644
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--- /dev/null
+++ b/src/osal/osal_freertos.h
@@ -0,0 +1,172 @@
+/* 
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Ha Thach (tinyusb.org)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * This file is part of the TinyUSB stack.
+ */
+
+#ifndef _TUSB_OSAL_FREERTOS_H_
+#define _TUSB_OSAL_FREERTOS_H_
+
+// FreeRTOS Headers
+#include TU_INCLUDE_PATH(CFG_TUSB_OS_INC_PATH,FreeRTOS.h)
+#include TU_INCLUDE_PATH(CFG_TUSB_OS_INC_PATH,semphr.h)
+#include TU_INCLUDE_PATH(CFG_TUSB_OS_INC_PATH,queue.h)
+#include TU_INCLUDE_PATH(CFG_TUSB_OS_INC_PATH,task.h)
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+//--------------------------------------------------------------------+
+// TASK API
+//--------------------------------------------------------------------+
+static inline void osal_task_delay(uint32_t msec)
+{
+  vTaskDelay( pdMS_TO_TICKS(msec) );
+}
+
+//--------------------------------------------------------------------+
+// Semaphore API
+//--------------------------------------------------------------------+
+typedef StaticSemaphore_t osal_semaphore_def_t;
+typedef SemaphoreHandle_t osal_semaphore_t;
+
+static inline osal_semaphore_t osal_semaphore_create(osal_semaphore_def_t* semdef)
+{
+  return xSemaphoreCreateBinaryStatic(semdef);
+}
+
+static inline bool osal_semaphore_post(osal_semaphore_t sem_hdl, bool in_isr)
+{
+  if ( !in_isr )
+  {
+    return xSemaphoreGive(sem_hdl) != 0;
+  }
+  else
+  {
+    BaseType_t xHigherPriorityTaskWoken;
+    BaseType_t res = xSemaphoreGiveFromISR(sem_hdl, &xHigherPriorityTaskWoken);
+
+#if CFG_TUSB_MCU == OPT_MCU_ESP32S2 || CFG_TUSB_MCU == OPT_MCU_ESP32S3
+    if ( xHigherPriorityTaskWoken ) portYIELD_FROM_ISR();
+#else
+    portYIELD_FROM_ISR(xHigherPriorityTaskWoken);
+#endif
+
+    return res != 0;
+  }
+}
+
+static inline bool osal_semaphore_wait (osal_semaphore_t sem_hdl, uint32_t msec)
+{
+  uint32_t const ticks = (msec == OSAL_TIMEOUT_WAIT_FOREVER) ? portMAX_DELAY : pdMS_TO_TICKS(msec);
+  return xSemaphoreTake(sem_hdl, ticks);
+}
+
+static inline void osal_semaphore_reset(osal_semaphore_t const sem_hdl)
+{
+  xQueueReset(sem_hdl);
+}
+
+//--------------------------------------------------------------------+
+// MUTEX API (priority inheritance)
+//--------------------------------------------------------------------+
+typedef StaticSemaphore_t osal_mutex_def_t;
+typedef SemaphoreHandle_t osal_mutex_t;
+
+static inline osal_mutex_t osal_mutex_create(osal_mutex_def_t* mdef)
+{
+  return xSemaphoreCreateMutexStatic(mdef);
+}
+
+static inline bool osal_mutex_lock (osal_mutex_t mutex_hdl, uint32_t msec)
+{
+  return osal_semaphore_wait(mutex_hdl, msec);
+}
+
+static inline bool osal_mutex_unlock(osal_mutex_t mutex_hdl)
+{
+  return xSemaphoreGive(mutex_hdl);
+}
+
+//--------------------------------------------------------------------+
+// QUEUE API
+//--------------------------------------------------------------------+
+
+// role device/host is used by OS NONE for mutex (disable usb isr) only
+#define OSAL_QUEUE_DEF(_role, _name, _depth, _type) \
+  static _type _name##_##buf[_depth];\
+  osal_queue_def_t _name = { .depth = _depth, .item_sz = sizeof(_type), .buf = _name##_##buf };
+
+typedef struct
+{
+  uint16_t depth;
+  uint16_t item_sz;
+  void*    buf;
+
+  StaticQueue_t sq;
+}osal_queue_def_t;
+
+typedef QueueHandle_t osal_queue_t;
+
+static inline osal_queue_t osal_queue_create(osal_queue_def_t* qdef)
+{
+  return xQueueCreateStatic(qdef->depth, qdef->item_sz, (uint8_t*) qdef->buf, &qdef->sq);
+}
+
+static inline bool osal_queue_receive(osal_queue_t qhdl, void* data)
+{
+  return xQueueReceive(qhdl, data, portMAX_DELAY);
+}
+
+static inline bool osal_queue_send(osal_queue_t qhdl, void const * data, bool in_isr)
+{
+  if ( !in_isr )
+  {
+    return xQueueSendToBack(qhdl, data, OSAL_TIMEOUT_WAIT_FOREVER) != 0;
+  }
+  else
+  {
+    BaseType_t xHigherPriorityTaskWoken;
+    BaseType_t res = xQueueSendToBackFromISR(qhdl, data, &xHigherPriorityTaskWoken);
+
+#if CFG_TUSB_MCU == OPT_MCU_ESP32S2 || CFG_TUSB_MCU == OPT_MCU_ESP32S3
+    if ( xHigherPriorityTaskWoken ) portYIELD_FROM_ISR();
+#else
+    portYIELD_FROM_ISR(xHigherPriorityTaskWoken);
+#endif
+
+    return res != 0;
+  }
+}
+
+static inline bool osal_queue_empty(osal_queue_t qhdl)
+{
+  return uxQueueMessagesWaiting(qhdl) == 0;
+}
+
+#ifdef __cplusplus
+ }
+#endif
+
+#endif /* _TUSB_OSAL_FREERTOS_H_ */