diff --git a/tests/test/host/ehci/test_pipe_bulk_xfer.c b/tests/test/host/ehci/test_pipe_bulk_xfer.c
index 71a833b46..6d3d0c4a7 100644
--- a/tests/test/host/ehci/test_pipe_bulk_xfer.c
+++ b/tests/test/host/ehci/test_pipe_bulk_xfer.c
@@ -202,7 +202,7 @@ void test_bulk_xfer_double(void)
   TEST_ASSERT_TRUE(p_tail->int_on_complete);
 }
 
-void test_bulk_xfer_isr(void)
+void test_bulk_xfer_complete_isr(void)
 {
   hcd_pipe_xfer(pipe_hdl_bulk, xfer_data, sizeof(xfer_data), false);
   hcd_pipe_xfer(pipe_hdl_bulk, data2, sizeof(data2), true);
@@ -212,7 +212,7 @@ void test_bulk_xfer_isr(void)
 
   ehci_controller_run(hostid);
 
-  usbh_isr_Expect(pipe_hdl_bulk, TUSB_CLASS_MSC);
+  usbh_isr_Expect(pipe_hdl_bulk, TUSB_CLASS_MSC, BUS_EVENT_XFER_COMPLETE);
 
   //------------- Code Under Test -------------//
   hcd_isr(hostid);
diff --git a/tests/test/host/ehci/test_pipe_control_xfer.c b/tests/test/host/ehci/test_pipe_control_xfer.c
index 19d2b7e21..432f5956e 100644
--- a/tests/test/host/ehci/test_pipe_control_xfer.c
+++ b/tests/test/host/ehci/test_pipe_control_xfer.c
@@ -235,7 +235,7 @@ void test_control_xfer_complete_isr(void)
 
   TEST_ASSERT_EQUAL_HEX(async_head, get_operational_register(hostid)->async_list_base);
   TEST_ASSERT_EQUAL_HEX((uint32_t) p_control_qhd, align32(async_head->next.address));
-  usbh_isr_Expect(((pipe_handle_t){.dev_addr = dev_addr}), 0);
+  usbh_isr_Expect(((pipe_handle_t){.dev_addr = dev_addr}), 0, BUS_EVENT_XFER_COMPLETE);
 
   //------------- Code Under TEST -------------//
   hcd_isr(hostid);
diff --git a/tinyusb/class/hid_host.h b/tinyusb/class/hid_host.h
index f85beef67..c0cb81702 100644
--- a/tinyusb/class/hid_host.h
+++ b/tinyusb/class/hid_host.h
@@ -89,7 +89,7 @@ tusb_error_t hidh_keyboard_install(uint8_t dev_addr, uint8_t const *descriptor)
 //--------------------------------------------------------------------+
 void         hidh_init(void) ATTR_WEAK;
 tusb_error_t hidh_open_subtask(uint8_t dev_addr, uint8_t const *descriptor, uint16_t *p_length) ATTR_WEAK ATTR_WARN_UNUSED_RESULT;
-void hidh_isr(pipe_handle_t pipe_hdl) ATTR_WEAK;
+void hidh_isr(pipe_handle_t pipe_hdl, tusb_bus_event_t event) ATTR_WEAK;
 void hidh_close(uint8_t dev_addr) ATTR_WEAK;
 
 #endif
diff --git a/tinyusb/class/msc_host.h b/tinyusb/class/msc_host.h
index 021d30412..f6222197d 100644
--- a/tinyusb/class/msc_host.h
+++ b/tinyusb/class/msc_host.h
@@ -70,7 +70,7 @@
 
 void         msch_init(void) ATTR_WEAK;
 tusb_error_t msch_open_subtask(uint8_t dev_addr, uint8_t const *descriptor, uint16_t *p_length) ATTR_WEAK ATTR_WARN_UNUSED_RESULT;
-void msch_isr(pipe_handle_t pipe_hdl) ATTR_WEAK;
+void msch_isr(pipe_handle_t pipe_hdl, tusb_bus_event_t event) ATTR_WEAK;
 void msch_close(uint8_t dev_addr) ATTR_WEAK;
 #endif
 
diff --git a/tinyusb/core/tusb_types.h b/tinyusb/core/tusb_types.h
index d9750c279..aff92aebb 100644
--- a/tinyusb/core/tusb_types.h
+++ b/tinyusb/core/tusb_types.h
@@ -164,6 +164,11 @@ enum tusb_device_state_{
   TUSB_DEVICE_STATE_SAFE_REMOVE ,
 };
 
+typedef enum {
+  BUS_EVENT_XFER_COMPLETE,
+  BUS_EVENT_XFER_ERROR
+}tusb_bus_event_t;
+
 #ifdef __cplusplus
  }
 #endif
diff --git a/tinyusb/host/ehci/ehci.c b/tinyusb/host/ehci/ehci.c
index e24548bc1..9d8bb16e7 100644
--- a/tinyusb/host/ehci/ehci.c
+++ b/tinyusb/host/ehci/ehci.c
@@ -224,7 +224,7 @@ void async_list_process_isr(ehci_qhd_t * const async_head, ehci_registers_t * co
             pipe_hdl.xfer_type = TUSB_XFER_BULK;
             pipe_hdl.index = qhd_get_index(p_qhd);
           }
-          usbh_isr( pipe_hdl, p_qhd->class_code); // call USBH call back
+          usbh_isr( pipe_hdl, p_qhd->class_code, BUS_EVENT_XFER_COMPLETE); // call USBH callback
         }
 
         p_qhd->p_qtd_list_head->used = 0; // free QTD
diff --git a/tinyusb/host/hcd.h b/tinyusb/host/hcd.h
index 129a4640f..98b5e5c5c 100644
--- a/tinyusb/host/hcd.h
+++ b/tinyusb/host/hcd.h
@@ -66,11 +66,6 @@ typedef struct {
   uint8_t index;
 } pipe_handle_t;
 
-typedef enum {
-  BUS_XFER_COMPLETE,
-  BUS_XFER_ERROR
-}usb_bus_event_t;
-
 //--------------------------------------------------------------------+
 // USBH-HCD API
 //--------------------------------------------------------------------+
diff --git a/tinyusb/host/usbh.c b/tinyusb/host/usbh.c
index f56291290..544c1a467 100644
--- a/tinyusb/host/usbh.c
+++ b/tinyusb/host/usbh.c
@@ -61,7 +61,7 @@ void tusb_tick_tock(void)
 #define ENUM_QUEUE_DEPTH  5
 
 // TODO fix number of class driver
-static class_driver_t const usbh_class_drivers[TUSB_CLASS_MAX_CONSEC_NUMBER] =
+static host_class_driver_t const usbh_class_drivers[TUSB_CLASS_MAX_CONSEC_NUMBER] =
 {
     [TUSB_CLASS_HID] = {
         .init = hidh_init,
@@ -179,14 +179,14 @@ pipe_status_t usbh_pipe_status_get(pipe_handle_t pipe_hdl)
 // USBH-HCD ISR/Callback API
 //--------------------------------------------------------------------+
 // interrupt caused by a TD (with IOC=1) in pipe of class class_code
-void usbh_isr(pipe_handle_t pipe_hdl, uint8_t class_code)
+void usbh_isr(pipe_handle_t pipe_hdl, uint8_t class_code, tusb_bus_event_t event)
 {
   if (class_code == 0) // Control transfer
   {
     osal_semaphore_post( usbh_device_info_pool[ pipe_hdl.dev_addr ].sem_hdl );
   }else if (usbh_class_drivers[class_code].isr)
   {
-    usbh_class_drivers[class_code].isr(pipe_hdl);
+    usbh_class_drivers[class_code].isr(pipe_hdl, event);
   }else
   {
     ASSERT(false, (void) 0); // something wrong, no one claims the isr's source
diff --git a/tinyusb/host/usbh.h b/tinyusb/host/usbh.h
index 1dae917f6..901a0f056 100644
--- a/tinyusb/host/usbh.h
+++ b/tinyusb/host/usbh.h
@@ -106,9 +106,9 @@ typedef uint8_t  tusbh_device_status_t;
 typedef struct {
   void (* const init) (void);
   tusb_error_t (* const open_subtask)(uint8_t, uint8_t const *, uint16_t*);
-  void (* const isr) (pipe_handle_t);
+  void (* const isr) (pipe_handle_t, tusb_bus_event_t);
   void (* const close) (uint8_t);
-} class_driver_t;
+} host_class_driver_t;
 //--------------------------------------------------------------------+
 // INTERNAL OBJECT & FUNCTION DECLARATION
 //--------------------------------------------------------------------+
diff --git a/tinyusb/host/usbh_hcd.h b/tinyusb/host/usbh_hcd.h
index bd0d09c55..d11b6e45f 100644
--- a/tinyusb/host/usbh_hcd.h
+++ b/tinyusb/host/usbh_hcd.h
@@ -101,7 +101,7 @@ typedef struct { // TODO internal structure, re-order members
 
 extern usbh_device_info_t usbh_device_info_pool[TUSB_CFG_HOST_DEVICE_MAX+1]; // including zero-address
 
-void usbh_isr(pipe_handle_t pipe_hdl, uint8_t class_code);
+void usbh_isr(pipe_handle_t pipe_hdl, uint8_t class_code, tusb_bus_event_t event);
 void usbh_device_plugged_isr(uint8_t hostid, tusb_speed_t speed);
 void usbh_device_unplugged_isr(uint8_t hostid);