add mutex support for osal

add test for mutex in test_osal_none.c
implement usbh_control_xfer using mutex to get access to queue xfer on control pipe
(while semaphore is used to sync with hcd DMA)
failed to issue control xfer: set idle & get report descriptor in hidh_open_subtask (more to work on)

11 files changed, 270 insertions, 29 deletions

diff --git a/tests/support/descriptor_test.c b/tests/support/descriptor_test.c
index a972da03e..725baa841 100644
--- a/tests/support/descriptor_test.c
+++ b/tests/support/descriptor_test.c
@@ -151,7 +151,7 @@ const app_configuration_desc_t desc_configuration =
         .bDescriptorType     = TUSB_DESC_TYPE_CONFIGURATION,
 
         .wTotalLength        = sizeof(app_configuration_desc_t) - 1, // exclude termination
-        .bNumInterfaces      = 1,
+        .bNumInterfaces      = 3,
 
         .bConfigurationValue = 1,
         .iConfiguration      = 0x00,
diff --git a/tests/test/test/host/host_helper.h b/tests/test/test/host/host_helper.h
index f4fdf62d4..97102c565 100644
--- a/tests/test/test/host/host_helper.h
+++ b/tests/test/test/host/host_helper.h
@@ -58,6 +58,7 @@ static inline void helper_usbh_init_expect(void)
   osal_semaphore_create_IgnoreAndReturn( (osal_semaphore_handle_t) 0x1234);
   osal_task_create_IgnoreAndReturn(TUSB_ERROR_NONE);
   osal_queue_create_IgnoreAndReturn( (osal_queue_handle_t) 0x4566 );
+  osal_mutex_create_IgnoreAndReturn((osal_mutex_handle_t) 0x789a);
 }
 
 static inline void helper_usbh_device_emulate(uint8_t dev_addr, uint8_t hub_addr, uint8_t hub_port, uint8_t hostid, tusb_speed_t speed)
diff --git a/tests/test/test/host/usbh/test_enum_task.c b/tests/test/test/host/usbh/test_enum_task.c
index 3d0f9f193..ae3fe34c5 100644
--- a/tests/test/test/host/usbh/test_enum_task.c
+++ b/tests/test/test/host/usbh/test_enum_task.c
@@ -50,7 +50,6 @@
 
 extern usbh_device_info_t usbh_devices[TUSB_CFG_HOST_DEVICE_MAX+1];
 extern uint8_t enum_data_buffer[TUSB_CFG_HOST_ENUM_BUFFER_SIZE];
-uint8_t dev_addr;
 
 usbh_enumerate_t const enum_connect = {
     .core_id  = 0,
@@ -70,12 +69,15 @@ void setUp(void)
 
   osal_queue_receive_StubWithCallback(queue_recv_stub);
   osal_semaphore_wait_StubWithCallback(semaphore_wait_success_stub);
+  osal_mutex_wait_StubWithCallback(semaphore_wait_success_stub);
+  osal_mutex_release_IgnoreAndReturn(TUSB_ERROR_NONE);
   hcd_pipe_control_xfer_StubWithCallback(control_xfer_stub);
 
   hcd_port_connect_status_ExpectAndReturn(enum_connect.core_id, true);
   hcd_port_reset_Expect(enum_connect.core_id);
   hcd_port_speed_get_ExpectAndReturn(enum_connect.core_id, device_speed);
   osal_semaphore_reset_Expect( usbh_devices[0].control.sem_hdl );
+  osal_mutex_reset_Expect( usbh_devices[0].control.mutex_hdl );
   hcd_pipe_control_open_ExpectAndReturn(0, 8, TUSB_ERROR_NONE);
 }
 
@@ -172,6 +174,7 @@ tusb_error_t hidh_install_stub(uint8_t dev_addr, tusb_descriptor_interface_t con
 void test_addr0_failed_dev_desc(void)
 {
   osal_semaphore_wait_StubWithCallback(semaphore_wait_timeout_stub(0));
+
   tusbh_device_mount_failed_cb_Expect(TUSB_ERROR_USBH_MOUNT_DEVICE_NOT_RESPOND, NULL);
 
   usbh_enumeration_task(NULL);
@@ -199,6 +202,7 @@ void test_enum_failed_get_full_dev_desc(void)
   hcd_pipe_control_close_ExpectAndReturn(0, TUSB_ERROR_NONE);
 
   osal_semaphore_reset_Expect( usbh_devices[0].control.sem_hdl );
+  osal_mutex_reset_Expect( usbh_devices[0].control.mutex_hdl );
   hcd_pipe_control_open_ExpectAndReturn(1, desc_device.bMaxPacketSize0, TUSB_ERROR_NONE);
   tusbh_device_mount_failed_cb_Expect(TUSB_ERROR_USBH_MOUNT_DEVICE_NOT_RESPOND, NULL);
 
@@ -218,6 +222,8 @@ void test_enum_failed_get_9byte_config_desc(void)
   hcd_port_reset_Expect( usbh_devices[0].core_id );
   hcd_pipe_control_close_ExpectAndReturn(0, TUSB_ERROR_NONE);
   osal_semaphore_reset_Expect( usbh_devices[0].control.sem_hdl );
+  osal_mutex_reset_Expect( usbh_devices[0].control.mutex_hdl );
+
   hcd_pipe_control_open_ExpectAndReturn(1, desc_device.bMaxPacketSize0, TUSB_ERROR_NONE);
   tusbh_device_attached_cb_ExpectAndReturn((tusb_descriptor_device_t*) enum_data_buffer, 1);
   tusbh_device_mount_failed_cb_Expect(TUSB_ERROR_USBH_MOUNT_DEVICE_NOT_RESPOND, NULL);
@@ -235,6 +241,7 @@ void test_enum_failed_get_full_config_desc(void)
   hcd_port_reset_Expect( usbh_devices[0].core_id );
   hcd_pipe_control_close_ExpectAndReturn(0, TUSB_ERROR_NONE);
   osal_semaphore_reset_Expect( usbh_devices[0].control.sem_hdl );
+  osal_mutex_reset_Expect( usbh_devices[0].control.mutex_hdl );
   hcd_pipe_control_open_ExpectAndReturn(1, desc_device.bMaxPacketSize0, TUSB_ERROR_NONE);
   tusbh_device_attached_cb_ExpectAndReturn((tusb_descriptor_device_t*) enum_data_buffer, 1);
   tusbh_device_mount_failed_cb_Expect(TUSB_ERROR_USBH_MOUNT_DEVICE_NOT_RESPOND, NULL);
@@ -253,6 +260,7 @@ void test_enum_parse_config_desc(void)
   hcd_port_reset_Expect( usbh_devices[0].core_id );
   hcd_pipe_control_close_ExpectAndReturn(0, TUSB_ERROR_NONE);
   osal_semaphore_reset_Expect( usbh_devices[0].control.sem_hdl );
+  osal_mutex_reset_Expect( usbh_devices[0].control.mutex_hdl );
   hcd_pipe_control_open_ExpectAndReturn(1, desc_device.bMaxPacketSize0, TUSB_ERROR_NONE);
   tusbh_device_attached_cb_ExpectAndReturn((tusb_descriptor_device_t*) enum_data_buffer, 1);
 
@@ -269,6 +277,7 @@ void test_enum_set_configure(void)
   hcd_port_reset_Expect( usbh_devices[0].core_id );
   hcd_pipe_control_close_ExpectAndReturn(0, TUSB_ERROR_NONE);
   osal_semaphore_reset_Expect( usbh_devices[0].control.sem_hdl );
+  osal_mutex_reset_Expect( usbh_devices[0].control.mutex_hdl );
   hcd_pipe_control_open_ExpectAndReturn(1, desc_device.bMaxPacketSize0, TUSB_ERROR_NONE);
   tusbh_device_attached_cb_ExpectAndReturn((tusb_descriptor_device_t*) enum_data_buffer, 1);
   class_install_expect();
diff --git a/tests/test/test/host/usbh/test_usbh.c b/tests/test/test/host/usbh/test_usbh.c
index b72fd2966..30f4a4dfc 100644
--- a/tests/test/test/host/usbh/test_usbh.c
+++ b/tests/test/test/host/usbh/test_usbh.c
@@ -90,7 +90,6 @@ void test_usbh_init_hcd_failed(void)
 void test_usbh_init_enum_task_create_failed(void)
 {
   hcd_init_ExpectAndReturn(TUSB_ERROR_NONE);
-  osal_semaphore_create_IgnoreAndReturn( (osal_semaphore_handle_t) 0x1234);
   osal_task_create_IgnoreAndReturn(TUSB_ERROR_OSAL_TASK_FAILED);
   TEST_ASSERT_EQUAL(TUSB_ERROR_OSAL_TASK_FAILED, usbh_init());
 }
@@ -98,12 +97,30 @@ void test_usbh_init_enum_task_create_failed(void)
 void test_usbh_init_enum_queue_create_failed(void)
 {
   hcd_init_ExpectAndReturn(TUSB_ERROR_NONE);
-  osal_semaphore_create_IgnoreAndReturn( (osal_semaphore_handle_t) 0x1234);
   osal_task_create_IgnoreAndReturn(TUSB_ERROR_NONE);
   osal_queue_create_IgnoreAndReturn(NULL);
   TEST_ASSERT_EQUAL(TUSB_ERROR_OSAL_QUEUE_FAILED, usbh_init());
 }
 
+void test_usbh_init_semaphore_create_failed(void)
+{
+  hcd_init_ExpectAndReturn(TUSB_ERROR_NONE);
+  osal_task_create_IgnoreAndReturn(TUSB_ERROR_NONE);
+  osal_queue_create_IgnoreAndReturn((osal_queue_handle_t) 0x1234);
+  osal_semaphore_create_IgnoreAndReturn(NULL);
+  TEST_ASSERT_EQUAL(TUSB_ERROR_OSAL_SEMAPHORE_FAILED, usbh_init());
+}
+
+void test_usbh_init_mutex_create_failed(void)
+{
+  hcd_init_ExpectAndReturn(TUSB_ERROR_NONE);
+  osal_task_create_IgnoreAndReturn(TUSB_ERROR_NONE);
+  osal_queue_create_IgnoreAndReturn((osal_queue_handle_t) 0x1234);
+  osal_semaphore_create_IgnoreAndReturn((osal_semaphore_handle_t) 0x1234);
+  osal_mutex_create_IgnoreAndReturn(NULL);
+  TEST_ASSERT_EQUAL(TUSB_ERROR_OSAL_MUTEX_FAILED, usbh_init());
+}
+
 void test_usbh_init_ok(void)
 {
   hcd_init_ExpectAndReturn(TUSB_ERROR_NONE);
@@ -151,3 +168,39 @@ void test_usbh_device_unplugged_isr(void)
 
   TEST_ASSERT_EQUAL(TUSB_DEVICE_STATE_REMOVING, usbh_devices[dev_addr].state);
 }
+
+void semaphore_wait_success_stub(osal_mutex_handle_t const sem_hdl, uint32_t msec, tusb_error_t *p_error, int num_call)
+{
+  (*p_error) = TUSB_ERROR_NONE;
+}
+
+static void mutex_wait_failed_stub(osal_mutex_handle_t const sem_hdl, uint32_t msec, tusb_error_t *p_error, int num_call)
+{
+  (*p_error) = TUSB_ERROR_OSAL_TIMEOUT;
+}
+
+void test_usbh_control_xfer_mutex_failed(void)
+{
+  tusb_std_request_t a_request;
+
+  osal_mutex_wait_StubWithCallback(mutex_wait_failed_stub);
+  osal_mutex_release_ExpectAndReturn(usbh_devices[dev_addr].control.mutex_hdl, TUSB_ERROR_NONE);
+
+  //------------- Code Under Test -------------//
+  usbh_control_xfer_subtask(dev_addr, &a_request, NULL);
+}
+
+void test_usbh_control_xfer_ok(void)
+{
+  tusb_std_request_t a_request;
+
+  osal_mutex_wait_StubWithCallback(semaphore_wait_success_stub);
+
+  hcd_pipe_control_xfer_ExpectAndReturn(dev_addr, &a_request, NULL, TUSB_ERROR_NONE);
+  osal_semaphore_wait_StubWithCallback(semaphore_wait_success_stub);
+
+  osal_mutex_release_ExpectAndReturn(usbh_devices[dev_addr].control.mutex_hdl, TUSB_ERROR_NONE);
+
+  //------------- Code Under Test -------------//
+  usbh_control_xfer_subtask(dev_addr, &a_request, NULL);
+}
diff --git a/tests/test/test/test_osal_none.c b/tests/test/test/test_osal_none.c
index 814a8602c..46e7d090d 100644
--- a/tests/test/test/test_osal_none.c
+++ b/tests/test/test/test_osal_none.c
@@ -54,11 +54,15 @@ osal_semaphore_handle_t sem_hdl;
 OSAL_QUEUE_DEF(queue, QUEUE_DEPTH, uint32_t);
 osal_queue_handle_t queue_hdl;
 
+OSAL_MUTEX_DEF(mutex);
+osal_mutex_handle_t mutex_hdl;
+
 void setUp(void)
 {
   memset(statements, 0, sizeof(statements));
   sem_hdl = osal_semaphore_create(OSAL_SEM_REF(sem));
   queue_hdl = osal_queue_create(&queue);
+  mutex_hdl = osal_mutex_create(OSAL_MUTEX_REF(mutex));
 }
 
 void tearDown(void)
@@ -83,6 +87,21 @@ void test_semaphore_post(void)
 // blocking service such as semaphore wait need to be invoked within a task's loop
 
 //--------------------------------------------------------------------+
+// Mutex
+//--------------------------------------------------------------------+
+void test_mutex_create(void)
+{
+  TEST_ASSERT_EQUAL_PTR(&mutex, mutex_hdl);
+  TEST_ASSERT_EQUAL(1, mutex);
+}
+
+void test_mutex_release(void)
+{
+  osal_mutex_release(mutex_hdl);
+  TEST_ASSERT_EQUAL(1, mutex);
+}
+
+//--------------------------------------------------------------------+
 // Queue
 //--------------------------------------------------------------------+
 void test_queue_create(void)
@@ -164,6 +183,76 @@ void test_task_with_semaphore(void)
 }
 
 //--------------------------------------------------------------------+
+// TASK MUTEX
+//--------------------------------------------------------------------+
+tusb_error_t mutex_sample_task1(void) // occupy mutex and not release it
+{
+  tusb_error_t error = TUSB_ERROR_NONE;
+
+  OSAL_TASK_LOOP_BEGIN
+
+  statements[0]++;
+
+  osal_mutex_wait(mutex_hdl, OSAL_TIMEOUT_WAIT_FOREVER, &error);
+  statements[2]++;
+
+  OSAL_TASK_LOOP_END
+}
+
+tusb_error_t mutex_sample_task2(void)
+{
+  tusb_error_t error = TUSB_ERROR_NONE;
+
+  OSAL_TASK_LOOP_BEGIN
+
+  statements[1]++;
+
+  osal_mutex_wait(mutex_hdl, OSAL_TIMEOUT_WAIT_FOREVER, &error);
+  statements[3]++;
+
+  osal_mutex_wait(mutex_hdl, OSAL_TIMEOUT_NORMAL, &error);
+  statements[5]++;
+
+  TEST_ASSERT_EQUAL(TUSB_ERROR_OSAL_TIMEOUT, error);
+
+  OSAL_TASK_LOOP_END
+}
+
+void test_task_with_mutex(void)
+{
+  // several invoke before mutex is available
+  mutex_sample_task1();
+  for(uint32_t i=0; i<10; i++) {
+    mutex_sample_task2();
+  }
+
+  TEST_ASSERT_EQUAL(1, statements[0]);
+  TEST_ASSERT_EQUAL(1, statements[2]);
+
+  TEST_ASSERT_EQUAL(1, statements[1]);
+  TEST_ASSERT_EQUAL(0, statements[3]);
+
+  // invoke after posting mutex
+  osal_mutex_release(mutex_hdl);
+  for(uint32_t i=0; i<10; i++) {
+    mutex_sample_task2();
+  }
+  TEST_ASSERT_EQUAL(1, statements[3]);
+  TEST_ASSERT_EQUAL(0, statements[5]);
+
+  // timeout
+  for(uint32_t i=0; i<(OSAL_TIMEOUT_NORMAL*TUSB_CFG_OS_TICKS_PER_SECOND)/1000 ; i++){ // one tick less
+    osal_tick_tock();
+  }
+  mutex_sample_task2();
+  TEST_ASSERT_EQUAL(0, statements[5]);
+  osal_tick_tock();
+
+  mutex_sample_task2();
+  TEST_ASSERT_EQUAL(1, statements[5]);
+}
+
+//--------------------------------------------------------------------+
 // TASK QUEUE
 //--------------------------------------------------------------------+
 tusb_error_t sample_task_with_queue(void)
@@ -205,7 +294,7 @@ void test_task_with_queue(void)
     sample_task_with_queue();
   TEST_ASSERT_EQUAL(1, statements[0]);
 
-  // invoke after posting semaphore
+  // invoke after sending to queue
   item = 0x1111;
   osal_queue_send(queue_hdl, &item);
   sample_task_with_queue();
diff --git a/tinyusb/class/hid_host.c b/tinyusb/class/hid_host.c
index bdadc5666..5d780a819 100644
--- a/tinyusb/class/hid_host.c
+++ b/tinyusb/class/hid_host.c
@@ -197,6 +197,7 @@ void hidh_init(void)
 #endif
 }
 
+//uint8_t report_descriptor[256] TUSB_CFG_ATTR_USBRAM;
 tusb_error_t hidh_open_subtask(uint8_t dev_addr, tusb_descriptor_interface_t const *p_interface_desc, uint16_t *p_length)
 {
   tusb_error_t error;
@@ -215,6 +216,8 @@ tusb_error_t hidh_open_subtask(uint8_t dev_addr, tusb_descriptor_interface_t con
   OSAL_SUBTASK_BEGIN
 
   //------------- SET IDLE request -------------//
+  // TODO this request can be stalled by device (indicate not supported),
+  // until we have clear stall handler, temporarily disable it.
 //  OSAL_SUBTASK_INVOKED_AND_WAIT(
 //    usbh_control_xfer_subtask(
 //      dev_addr,
@@ -230,6 +233,22 @@ tusb_error_t hidh_open_subtask(uint8_t dev_addr, tusb_descriptor_interface_t con
 //  );
 
   //------------- TODO skip Get Report Descriptor -------------//
+//  memclr_(report_descriptor, 256);
+
+//  OSAL_SUBTASK_INVOKED_AND_WAIT(
+//    usbh_control_xfer_subtask(
+//      dev_addr,
+//      &(tusb_std_request_t)
+//      {
+//        .bmRequestType = { .direction = TUSB_DIR_DEV_TO_HOST, .type = TUSB_REQUEST_TYPE_STANDARD, .recipient = TUSB_REQUEST_RECIPIENT_INTERFACE },
+//        .bRequest      = TUSB_REQUEST_GET_DESCRIPTOR,
+//        .wValue        = HID_DESC_TYPE_REPORT,
+//        .wIndex        = p_interface_desc->bInterfaceNumber,
+//        .wLength       = p_desc_hid->wReportLength,
+//      },
+//      report_descriptor ),
+//    error
+//  );
 //  uint8_t *p_report_desc = NULL; // report descriptor has to be global & in USB RAM
 
   if ( HID_SUBCLASS_BOOT == p_interface_desc->bInterfaceSubClass )
diff --git a/tinyusb/common/errors.h b/tinyusb/common/errors.h
index 9017d99f4..dc9908bfd 100644
--- a/tinyusb/common/errors.h
+++ b/tinyusb/common/errors.h
@@ -74,6 +74,7 @@
     ENTRY(TUSB_ERROR_OSAL_TASK_CREATE_FAILED         )\
     ENTRY(TUSB_ERROR_OSAL_QUEUE_FAILED               )\
     ENTRY(TUSB_ERROR_OSAL_SEMAPHORE_FAILED           )\
+    ENTRY(TUSB_ERROR_OSAL_MUTEX_FAILED               )\
     ENTRY(TUSB_ERROR_EHCI_NOT_ENOUGH_QTD             )\
     ENTRY(TUSB_ERROR_USBD_DESCRIPTOR_STRING          )\
     ENTRY(TUSB_ERROR_HIDD_DESCRIPTOR_INTERFACE       )\
diff --git a/tinyusb/host/usbh.c b/tinyusb/host/usbh.c
index 419b1a534..90ee096cd 100644
--- a/tinyusb/host/usbh.c
+++ b/tinyusb/host/usbh.c
@@ -144,23 +144,30 @@ tusb_error_t usbh_init(void)
 
   ASSERT_STATUS( hcd_init() );
 
-  //------------- Semaphore for Control Pipe -------------//
-  for(uint8_t i=0; i<TUSB_CFG_HOST_DEVICE_MAX+1; i++) // including address zero
-  {
-    usbh_devices[i].control.sem_hdl = osal_semaphore_create( OSAL_SEM_REF(usbh_devices[i].control.semaphore) );
-    ASSERT_PTR(usbh_devices[i].control.sem_hdl, TUSB_ERROR_OSAL_SEMAPHORE_FAILED);
-  }
-
   //------------- Enumeration & Reporter Task init -------------//
   ASSERT_STATUS( osal_task_create(&enum_task_def) );
   enum_queue_hdl = osal_queue_create(&enum_queue_def);
   ASSERT_PTR(enum_queue_hdl, TUSB_ERROR_OSAL_QUEUE_FAILED);
 
+  //------------- Semaphore, Mutex for Control Pipe -------------//
+  for(uint8_t i=0; i<TUSB_CFG_HOST_DEVICE_MAX+1; i++) // including address zero
+  {
+    usbh_device_info_t * const p_device = &usbh_devices[i];
+
+    p_device->control.sem_hdl = osal_semaphore_create( OSAL_SEM_REF(p_device->control.semaphore) );
+    ASSERT_PTR(p_device->control.sem_hdl, TUSB_ERROR_OSAL_SEMAPHORE_FAILED);
+
+    p_device->control.mutex_hdl = osal_mutex_create ( OSAL_SEM_REF(p_device->control.mutex) );
+    ASSERT_PTR(p_device->control.mutex_hdl, TUSB_ERROR_OSAL_MUTEX_FAILED);
+  }
+
   //------------- class init -------------//
   for (uint8_t class_index = 1; class_index < TUSB_CLASS_MAPPED_INDEX_END; class_index++)
   {
     if (usbh_class_drivers[class_index].init)
+    {
       usbh_class_drivers[class_index].init();
+    }
   }
 
   return TUSB_ERROR_NONE;
@@ -174,11 +181,17 @@ tusb_error_t usbh_control_xfer_subtask(uint8_t dev_addr, tusb_std_request_t cons
 
   OSAL_SUBTASK_BEGIN
 
-  usbh_devices[dev_addr].control.pipe_status = TUSB_INTERFACE_STATUS_BUSY;
+  osal_mutex_wait(usbh_devices[dev_addr].control.mutex_hdl, OSAL_TIMEOUT_NORMAL, &error);
+  SUBTASK_ASSERT_STATUS_WITH_HANDLER(error, osal_mutex_release(usbh_devices[dev_addr].control.mutex_hdl));
+
   usbh_devices[dev_addr].control.request = *p_request;
-  SUBTASK_ASSERT_STATUS( hcd_pipe_control_xfer(dev_addr, &usbh_devices[dev_addr].control.request, data) );
+  /*SUBTASK_ASSERT_STATUS*/ (void) ( hcd_pipe_control_xfer(dev_addr, &usbh_devices[dev_addr].control.request, data) );
+  usbh_devices[dev_addr].control.pipe_status = TUSB_INTERFACE_STATUS_BUSY;
 
   osal_semaphore_wait(usbh_devices[dev_addr].control.sem_hdl, OSAL_TIMEOUT_NORMAL, &error); // careful of local variable without static
+
+  osal_mutex_release(usbh_devices[dev_addr].control.mutex_hdl);
+
   // TODO make handler for this function general purpose
   SUBTASK_ASSERT_WITH_HANDLER(TUSB_ERROR_NONE == error && usbh_devices[dev_addr].control.pipe_status != TUSB_INTERFACE_STATUS_ERROR,
                                      tusbh_device_mount_failed_cb(TUSB_ERROR_USBH_MOUNT_DEVICE_NOT_RESPOND, NULL) );
@@ -190,6 +203,7 @@ tusb_error_t usbh_pipe_control_open(uint8_t dev_addr, uint8_t max_packet_size) A
 tusb_error_t usbh_pipe_control_open(uint8_t dev_addr, uint8_t max_packet_size)
 {
   osal_semaphore_reset( usbh_devices[dev_addr].control.sem_hdl );
+  osal_mutex_reset( usbh_devices[dev_addr].control.mutex_hdl );
 
   ASSERT_STATUS( hcd_pipe_control_open(dev_addr, max_packet_size) );
 
diff --git a/tinyusb/host/usbh_hcd.h b/tinyusb/host/usbh_hcd.h
index fa676dfc9..fbb7379a7 100644
--- a/tinyusb/host/usbh_hcd.h
+++ b/tinyusb/host/usbh_hcd.h
@@ -92,15 +92,19 @@ typedef struct { // TODO internal structure, re-order members
   uint8_t interface_count; // bNumInterfaces alias
 
   //------------- device -------------//
-  volatile uint8_t state;          // device state, value from enum tusbh_device_state_t
-  uint32_t flag_supported_class; // a bitmap of supported class
+  volatile uint8_t state;             // device state, value from enum tusbh_device_state_t
+  uint32_t flag_supported_class;      // a bitmap of supported class
 
   //------------- control pipe -------------//
   struct {
     volatile uint8_t pipe_status;
     tusb_std_request_t request;
-    OSAL_SEM_DEF(semaphore); // TODO move to semaphore pool
-    osal_semaphore_handle_t sem_hdl;
+
+    OSAL_SEM_DEF(semaphore);          // TODO move to semaphore pool ?
+    osal_semaphore_handle_t sem_hdl;  // used to synchronize with HCD when control xfer complete
+
+    OSAL_MUTEX_DEF(mutex);            // TODO move to mutex pool ?
+    osal_mutex_handle_t mutex_hdl;    // used to exclusively occupy control pipe
   } control;
 } usbh_device_info_t;
 
diff --git a/tinyusb/osal/osal.h b/tinyusb/osal/osal.h
index c28bc4790..f40900919 100644
--- a/tinyusb/osal/osal.h
+++ b/tinyusb/osal/osal.h
@@ -133,12 +133,28 @@ typedef osal_semaphore_t * osal_semaphore_handle_t;
 #define OSAL_SEM_REF(name)\
   &name
 
-osal_semaphore_handle_t osal_semaphore_create(osal_semaphore_t * const sem);
-void osal_semaphore_wait(osal_semaphore_handle_t const sem_hdl, uint32_t msec, tusb_error_t *p_error);
-tusb_error_t osal_semaphore_post(osal_semaphore_handle_t const sem_hdl);
-void osal_semaphore_reset(osal_semaphore_handle_t const sem_hdl);
+osal_semaphore_handle_t osal_semaphore_create(osal_semaphore_t * p_sem);
+void osal_semaphore_wait(osal_semaphore_handle_t sem_hdl, uint32_t msec, tusb_error_t *p_error);
+tusb_error_t osal_semaphore_post(osal_semaphore_handle_t sem_hdl);
+void osal_semaphore_reset(osal_semaphore_handle_t sem_hdl);
 
 //--------------------------------------------------------------------+
+// MUTEX API (priority inheritance)
+//--------------------------------------------------------------------+
+#define OSAL_MUTEX_DEF(name)\
+  osal_mutex_t name
+
+#define OSAL_MUTEX_REF(name)\
+  &name
+
+typedef osal_semaphore_t        osal_mutex_t;
+typedef osal_semaphore_handle_t osal_mutex_handle_t;
+
+osal_mutex_handle_t osal_mutex_create(osal_mutex_t * p_mutex);
+void osal_mutex_wait(osal_mutex_handle_t mutex_hdl, uint32_t msec, tusb_error_t *p_error);
+tusb_error_t osal_mutex_release(osal_mutex_handle_t mutex_hdl);
+void osal_mutex_reset(osal_mutex_handle_t mutex_hdl);
+//--------------------------------------------------------------------+
 // QUEUE API
 //--------------------------------------------------------------------+
 typedef struct{
diff --git a/tinyusb/osal/osal_none.h b/tinyusb/osal/osal_none.h
index 936513d1b..5090d14f5 100644
--- a/tinyusb/osal/osal_none.h
+++ b/tinyusb/osal/osal_none.h
@@ -166,23 +166,23 @@ typedef osal_semaphore_t * osal_semaphore_handle_t;
 #define OSAL_SEM_REF(name)\
   &name
 
-static inline osal_semaphore_handle_t osal_semaphore_create(osal_semaphore_t * const p_sem) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE;
-static inline osal_semaphore_handle_t osal_semaphore_create(osal_semaphore_t * const p_sem)
+static inline osal_semaphore_handle_t osal_semaphore_create(osal_semaphore_t * p_sem) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE;
+static inline osal_semaphore_handle_t osal_semaphore_create(osal_semaphore_t * p_sem)
 {
-  (*p_sem) = 0;
+  (*p_sem) = 0; // TODO consider to have initial count parameter
   return (osal_semaphore_handle_t) p_sem;
 }
 
-static inline  tusb_error_t osal_semaphore_post(osal_semaphore_handle_t const sem_hdl) ATTR_ALWAYS_INLINE;
-static inline  tusb_error_t osal_semaphore_post(osal_semaphore_handle_t const sem_hdl)
+static inline  tusb_error_t osal_semaphore_post(osal_semaphore_handle_t sem_hdl) ATTR_ALWAYS_INLINE;
+static inline  tusb_error_t osal_semaphore_post(osal_semaphore_handle_t sem_hdl)
 {
   (*sem_hdl)++;
 
   return TUSB_ERROR_NONE;
 }
 
-static inline void osal_semaphore_reset(osal_semaphore_handle_t const sem_hdl) ATTR_ALWAYS_INLINE;
-static inline void osal_semaphore_reset(osal_semaphore_handle_t const sem_hdl)
+static inline void osal_semaphore_reset(osal_semaphore_handle_t sem_hdl) ATTR_ALWAYS_INLINE;
+static inline void osal_semaphore_reset(osal_semaphore_handle_t sem_hdl)
 {
   (*sem_hdl) = 0;
 }
@@ -203,6 +203,41 @@ static inline void osal_semaphore_reset(osal_semaphore_handle_t const sem_hdl)
   }while(0)
 
 //--------------------------------------------------------------------+
+// MUTEX API (priority inheritance)
+//--------------------------------------------------------------------+
+typedef osal_semaphore_t        osal_mutex_t;
+typedef osal_semaphore_handle_t osal_mutex_handle_t;
+
+#define OSAL_MUTEX_DEF(name)\
+  osal_mutex_t name
+
+#define OSAL_MUTEX_REF(name)\
+  &name
+
+static inline osal_mutex_handle_t osal_mutex_create(osal_mutex_t * p_mutex) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE;
+static inline osal_mutex_handle_t osal_mutex_create(osal_mutex_t * p_mutex)
+{
+  (*p_mutex) = 1;
+  return (osal_mutex_handle_t) p_mutex;
+}
+
+static inline  tusb_error_t osal_mutex_release(osal_mutex_handle_t mutex_hdl) ATTR_ALWAYS_INLINE;
+static inline  tusb_error_t osal_mutex_release(osal_mutex_handle_t mutex_hdl)
+{
+  (*mutex_hdl) = 1; // mutex is a binary semaphore
+
+  return TUSB_ERROR_NONE;
+}
+
+static inline void osal_mutex_reset(osal_mutex_handle_t mutex_hdl) ATTR_ALWAYS_INLINE;
+static inline void osal_mutex_reset(osal_mutex_handle_t mutex_hdl)
+{
+  (*mutex_hdl) = 1;
+}
+
+#define osal_mutex_wait osal_semaphore_wait
+
+//--------------------------------------------------------------------+
 // QUEUE API
 //--------------------------------------------------------------------+
 typedef struct{