diff --git a/src/class/msc/msc_host.c b/src/class/msc/msc_host.c
index 72f4afa27..1053d42d2 100644
--- a/src/class/msc/msc_host.c
+++ b/src/class/msc/msc_host.c
@@ -76,7 +76,7 @@ bool tuh_msc_is_mounted(uint8_t dev_addr)
 bool tuh_msc_is_busy(uint8_t dev_addr)
 {
   return  msch_data[dev_addr-1].is_initialized &&
-          hcd_pipe_is_busy(dev_addr, msch_data[dev_addr-1].bulk_in);
+          hcd_pipe_is_busy(dev_addr, msch_data[dev_addr-1].ep_in);
 }
 
 uint8_t const* tuh_msc_get_vendor_name(uint8_t dev_addr)
@@ -116,16 +116,16 @@ static tusb_error_t msch_command_xfer(uint8_t dev_addr, msch_interface_t * p_msc
   { // there is data phase
     if (p_msch->cbw.dir & TUSB_DIR_IN_MASK)
     {
-      TU_ASSERT( hcd_pipe_xfer(dev_addr, p_msch->bulk_out, (uint8_t*) &p_msch->cbw, sizeof(msc_cbw_t), false), TUSB_ERROR_FAILED );
-      TU_ASSERT( hcd_pipe_queue_xfer(dev_addr, p_msch->bulk_in , p_buffer, p_msch->cbw.total_bytes), TUSB_ERROR_FAILED );
+      TU_ASSERT( hcd_pipe_xfer(dev_addr, p_msch->ep_out, (uint8_t*) &p_msch->cbw, sizeof(msc_cbw_t), false), TUSB_ERROR_FAILED );
+      TU_ASSERT( hcd_pipe_queue_xfer(dev_addr, p_msch->ep_in , p_buffer, p_msch->cbw.total_bytes), TUSB_ERROR_FAILED );
     }else
     {
-      TU_ASSERT( hcd_pipe_queue_xfer(dev_addr, p_msch->bulk_out, (uint8_t*) &p_msch->cbw, sizeof(msc_cbw_t)), TUSB_ERROR_FAILED );
-      TU_ASSERT( hcd_pipe_xfer(dev_addr, p_msch->bulk_out , p_buffer, p_msch->cbw.total_bytes, false), TUSB_ERROR_FAILED );
+      TU_ASSERT( hcd_pipe_queue_xfer(dev_addr, p_msch->ep_out, (uint8_t*) &p_msch->cbw, sizeof(msc_cbw_t)), TUSB_ERROR_FAILED );
+      TU_ASSERT( hcd_pipe_xfer(dev_addr, p_msch->ep_out , p_buffer, p_msch->cbw.total_bytes, false), TUSB_ERROR_FAILED );
     }
   }
 
-  TU_ASSERT( hcd_pipe_xfer(dev_addr, p_msch->bulk_in , (uint8_t*) &p_msch->csw, sizeof(msc_csw_t), true), TUSB_ERROR_FAILED);
+  TU_ASSERT( hcd_pipe_xfer(dev_addr, p_msch->ep_in , (uint8_t*) &p_msch->csw, sizeof(msc_csw_t), true), TUSB_ERROR_FAILED);
 
   return TUSB_ERROR_NONE;
 }
@@ -225,8 +225,8 @@ tusb_error_t tuh_msc_test_unit_ready(uint8_t dev_addr, uint8_t lun,  msc_csw_t *
   memcpy(p_msch->cbw.command, &cmd_test_unit_ready, p_msch->cbw.cmd_len);
 
   // TODO MSCH refractor test uinit ready
-  TU_ASSERT( hcd_pipe_xfer(dev_addr, p_msch->bulk_out, (uint8_t*) &p_msch->cbw, sizeof(msc_cbw_t), false), TUSB_ERROR_FAILED );
-  TU_ASSERT( hcd_pipe_xfer(dev_addr, p_msch->bulk_in , (uint8_t*) p_csw, sizeof(msc_csw_t), true), TUSB_ERROR_FAILED );
+  TU_ASSERT( hcd_pipe_xfer(dev_addr, p_msch->ep_out, (uint8_t*) &p_msch->cbw, sizeof(msc_cbw_t), false), TUSB_ERROR_FAILED );
+  TU_ASSERT( hcd_pipe_xfer(dev_addr, p_msch->ep_in , (uint8_t*) p_csw, sizeof(msc_csw_t), true), TUSB_ERROR_FAILED );
 
   return TUSB_ERROR_NONE;
 }
@@ -307,11 +307,7 @@ bool msch_open(uint8_t rhport, uint8_t dev_addr, tusb_desc_interface_t const *it
     TU_ASSERT(TUSB_DESC_ENDPOINT == ep_desc->bDescriptorType);
     TU_ASSERT(TUSB_XFER_BULK == ep_desc->bmAttributes.xfer);
 
-    pipe_handle_t * p_pipe_hdl =  ( ep_desc->bEndpointAddress &  TUSB_DIR_IN_MASK ) ?
-        &p_msc->bulk_in : &p_msc->bulk_out;
-
-    (*p_pipe_hdl) = hcd_pipe_open(rhport, dev_addr, ep_desc);
-    TU_ASSERT( pipehandle_is_valid(*p_pipe_hdl) );
+    TU_ASSERT(hcd_pipe_open(rhport, dev_addr, ep_desc));
 
     if ( edpt_dir(ep_desc->bEndpointAddress) ==  TUSB_DIR_IN )
     {
@@ -365,7 +361,7 @@ bool msch_open(uint8_t rhport, uint8_t dev_addr, tusb_desc_interface_t const *it
 
   // NOTE: my toshiba thumb-drive stall the first Read Capacity and require the sequence
   // Read Capacity --> Stalled --> Clear Stall --> Request Sense --> Read Capacity (2) to work
-  if ( hcd_pipe_is_stalled(dev_addr, p_msc->bulk_in) )
+  if ( hcd_pipe_is_stalled(dev_addr, p_msc->ep_in) )
   {
     // clear stall TODO abstract clear stall function
     request = (tusb_control_request_t) {
@@ -378,7 +374,7 @@ bool msch_open(uint8_t rhport, uint8_t dev_addr, tusb_desc_interface_t const *it
 
     TU_ASSERT(usbh_control_xfer( dev_addr, &request, NULL ));
 
-    hcd_pipe_clear_stall(dev_addr, p_msc->bulk_in);
+    hcd_pipe_clear_stall(dev_addr, p_msc->ep_in);
     TU_ASSERT( osal_semaphore_wait(msch_sem_hdl, SCSI_XFER_TIMEOUT) ); // wait for SCSI status
 
     //------------- SCSI Request Sense -------------//
@@ -417,8 +413,8 @@ void msch_isr(uint8_t dev_addr, uint8_t ep_addr, xfer_result_t event, uint32_t x
 
 void msch_close(uint8_t dev_addr)
 {
-  (void) hcd_pipe_close(TUH_OPT_RHPORT, dev_addr, msch_data[dev_addr-1].bulk_in);
-  (void) hcd_pipe_close(TUH_OPT_RHPORT, dev_addr, msch_data[dev_addr-1].bulk_out);
+  (void) hcd_pipe_close(TUH_OPT_RHPORT, dev_addr, msch_data[dev_addr-1].ep_in);
+  (void) hcd_pipe_close(TUH_OPT_RHPORT, dev_addr, msch_data[dev_addr-1].ep_out);
 
   tu_memclr(&msch_data[dev_addr-1], sizeof(msch_interface_t));
   osal_semaphore_reset(msch_sem_hdl);
diff --git a/src/class/msc/msc_host.h b/src/class/msc/msc_host.h
index a77b494ed..968d221b4 100644
--- a/src/class/msc/msc_host.h
+++ b/src/class/msc/msc_host.h
@@ -187,9 +187,8 @@ void tuh_msc_isr(uint8_t dev_addr, xfer_result_t event, uint32_t xferred_bytes);
 //--------------------------------------------------------------------+
 #ifdef _TINY_USB_SOURCE_FILE_
 
-typedef struct {
-  pipe_handle_t bulk_in, bulk_out;
-
+typedef struct
+{
   uint8_t itf_numr;
   uint8_t  ep_in;
   uint8_t  ep_out;
diff --git a/src/host/ehci/ehci.c b/src/host/ehci/ehci.c
index f9b9db797..c36bfe181 100644
--- a/src/host/ehci/ehci.c
+++ b/src/host/ehci/ehci.c
@@ -75,11 +75,10 @@ static inline ehci_link_t* get_period_head(uint8_t hostid, uint8_t interval_ms)
 static inline ehci_qhd_t* get_control_qhd(uint8_t dev_addr) ATTR_ALWAYS_INLINE ATTR_PURE ATTR_WARN_UNUSED_RESULT;
 static inline ehci_qtd_t* get_control_qtds(uint8_t dev_addr) ATTR_ALWAYS_INLINE ATTR_PURE ATTR_WARN_UNUSED_RESULT;
 
-static inline uint8_t        qhd_get_index(ehci_qhd_t const * p_qhd) ATTR_ALWAYS_INLINE ATTR_PURE;
 static inline ehci_qhd_t*    qhd_next(ehci_qhd_t const * p_qhd) ATTR_ALWAYS_INLINE ATTR_PURE;
 static inline ehci_qhd_t*    qhd_find_free (void);
 static inline tusb_xfer_type_t qhd_get_xfer_type(ehci_qhd_t const * p_qhd) ATTR_ALWAYS_INLINE ATTR_PURE;
-static inline ehci_qhd_t* qhd_get_from_pipe_handle(uint8_t dev_addr, uint8_t ep_addr);
+static inline ehci_qhd_t* qhd_get_from_addr(uint8_t dev_addr, uint8_t ep_addr);
 
 // determine if a queue head has bus-related error
 static inline bool qhd_has_xact_error(ehci_qhd_t * p_qhd)
@@ -435,7 +434,7 @@ bool hcd_pipe_open(uint8_t rhport, uint8_t dev_addr, tusb_desc_endpoint_t const
 bool hcd_pipe_queue_xfer(uint8_t dev_addr, uint8_t ep_addr, uint8_t buffer[], uint16_t total_bytes)
 {
   //------------- set up QTD -------------//
-  ehci_qhd_t *p_qhd = qhd_get_from_pipe_handle(dev_addr, ep_addr);
+  ehci_qhd_t *p_qhd = qhd_get_from_addr(dev_addr, ep_addr);
   ehci_qtd_t *p_qtd = qtd_find_free(dev_addr);
 
   TU_ASSERT(p_qtd);
@@ -453,7 +452,7 @@ bool hcd_pipe_xfer(uint8_t dev_addr, uint8_t ep_addr, uint8_t buffer[], uint16_t
 {
   TU_ASSERT ( hcd_pipe_queue_xfer(dev_addr, ep_addr, buffer, total_bytes) );
 
-  ehci_qhd_t *p_qhd = qhd_get_from_pipe_handle(dev_addr, ep_addr);
+  ehci_qhd_t *p_qhd = qhd_get_from_addr(dev_addr, ep_addr);
 
   if ( int_on_complete )
   { // the just added qtd is pointed by list_tail
@@ -467,7 +466,7 @@ bool hcd_pipe_xfer(uint8_t dev_addr, uint8_t ep_addr, uint8_t buffer[], uint16_t
 /// pipe_close should only be called as a part of unmount/safe-remove process
 bool hcd_pipe_close(uint8_t rhport, uint8_t dev_addr, uint8_t ep_addr)
 {
-  ehci_qhd_t *p_qhd = qhd_get_from_pipe_handle(dev_addr, ep_addr);
+  ehci_qhd_t *p_qhd = qhd_get_from_addr(dev_addr, ep_addr);
 
   // async list needs async advance handshake to make sure host controller has released cached data
   // non-control does not use async advance, it will eventually free by control pipe close
@@ -494,19 +493,19 @@ bool hcd_pipe_close(uint8_t rhport, uint8_t dev_addr, uint8_t ep_addr)
 
 bool hcd_pipe_is_busy(uint8_t dev_addr, uint8_t ep_addr)
 {
-  ehci_qhd_t *p_qhd = qhd_get_from_pipe_handle(dev_addr, ep_addr);
+  ehci_qhd_t *p_qhd = qhd_get_from_addr(dev_addr, ep_addr);
   return !p_qhd->qtd_overlay.halted && (p_qhd->p_qtd_list_head != NULL);
 }
 
 bool hcd_pipe_is_stalled(uint8_t dev_addr, uint8_t ep_addr)
 {
-  ehci_qhd_t *p_qhd = qhd_get_from_pipe_handle(dev_addr, ep_addr);
+  ehci_qhd_t *p_qhd = qhd_get_from_addr(dev_addr, ep_addr);
   return p_qhd->qtd_overlay.halted && !qhd_has_xact_error(p_qhd);
 }
 
 tusb_error_t hcd_pipe_clear_stall(uint8_t dev_addr, uint8_t ep_addr)
 {
-  ehci_qhd_t *p_qhd = qhd_get_from_pipe_handle(dev_addr, ep_addr);
+  ehci_qhd_t *p_qhd = qhd_get_from_addr(dev_addr, ep_addr);
   p_qhd->qtd_overlay.halted = 0;
   // TODO reset data toggle ?
   return TUSB_ERROR_NONE;
@@ -839,7 +838,7 @@ static inline ehci_qhd_t* qhd_next(ehci_qhd_t const * p_qhd)
   return (ehci_qhd_t*) tu_align32(p_qhd->next.address);
 }
 
-static inline ehci_qhd_t* qhd_get_from_pipe_handle(uint8_t dev_addr, uint8_t ep_addr)
+static inline ehci_qhd_t* qhd_get_from_addr(uint8_t dev_addr, uint8_t ep_addr)
 {
   ehci_qhd_t* qhd_pool = ehci_data.qhd_pool;
 
diff --git a/src/host/hcd.h b/src/host/hcd.h
index f19812379..3c34a5609 100644
--- a/src/host/hcd.h
+++ b/src/host/hcd.h
@@ -49,6 +49,9 @@
  extern "C" {
 #endif
 
+ //--------------------------------------------------------------------+
+// MACRO CONSTANT TYPEDEF
+//--------------------------------------------------------------------+
 typedef enum
 {
   HCD_EVENT_DEVICE_ATTACH,
@@ -92,13 +95,6 @@ enum {
 //#define HCD_MAX_XFER 16
 #endif
 
-//--------------------------------------------------------------------+
-// MACRO CONSTANT TYPEDEF
-//--------------------------------------------------------------------+
-typedef struct {
-  uint8_t reserved[4];
-} pipe_handle_t;
-
 //--------------------------------------------------------------------+
 // USBH-HCD API
 //--------------------------------------------------------------------+
@@ -131,7 +127,6 @@ bool hcd_edpt_xfer(uint8_t rhport, uint8_t dev_addr, uint8_t ep_addr, uint8_t *
 // PIPE API
 //--------------------------------------------------------------------+
 // TODO control xfer should be used via usbh layer
-
 bool hcd_pipe_open(uint8_t rhport, uint8_t dev_addr, tusb_desc_endpoint_t const * ep_desc);
 bool hcd_pipe_queue_xfer(uint8_t dev_addr, uint8_t ep_addr, uint8_t buffer[], uint16_t total_bytes); // only queue, not transferring yet
 bool hcd_pipe_xfer(uint8_t dev_addr, uint8_t ep_addr, uint8_t buffer[], uint16_t total_bytes, bool int_on_complete);