Merge branch 'master' into fork/IngHK/cdch_upgrade

# Conflicts:
#	README.rst
#	docs/reference/index.rst
#	src/class/cdc/cdc_device.c
#	src/class/cdc/cdc_host.c

4 files changed, 327 insertions, 324 deletions

diff --git a/src/class/cdc/cdc_device.c b/src/class/cdc/cdc_device.c
index 9f51a6d4b..4d19adeb4 100644
--- a/src/class/cdc/cdc_device.c
+++ b/src/class/cdc/cdc_device.c
@@ -43,24 +43,19 @@
 //--------------------------------------------------------------------+
 // MACRO CONSTANT TYPEDEF
 //--------------------------------------------------------------------+
-enum
-{
-  BULK_PACKET_SIZE = (TUD_OPT_HIGH_SPEED ? 512 : 64)
-};
+#define BULK_PACKET_SIZE (TUD_OPT_HIGH_SPEED ? 512 : 64)
 
-typedef struct
-{
+typedef struct {
   uint8_t itf_num;
   uint8_t ep_notif;
   uint8_t ep_in;
   uint8_t ep_out;
 
   // Bit 0:  DTR (Data Terminal Ready), Bit 1: RTS (Request to Send)
-  // TODO use cdc_line_control_state_t instead of uint8_t
   uint8_t line_state;
 
   /*------------- From this point, data is not cleared by bus reset -------------*/
-  char    wanted_char;
+  char wanted_char;
   TU_ATTR_ALIGNED(4) cdc_line_coding_t line_coding;
 
   // FIFO
@@ -72,30 +67,38 @@ typedef struct
 
   OSAL_MUTEX_DEF(rx_ff_mutex);
   OSAL_MUTEX_DEF(tx_ff_mutex);
-
-  // Endpoint Transfer buffer
-  CFG_TUSB_MEM_ALIGN uint8_t epout_buf[CFG_TUD_CDC_EP_BUFSIZE];
-  CFG_TUSB_MEM_ALIGN uint8_t epin_buf[CFG_TUD_CDC_EP_BUFSIZE];
-
-}cdcd_interface_t;
+} cdcd_interface_t;
 
 #define ITF_MEM_RESET_SIZE   offsetof(cdcd_interface_t, wanted_char)
 
+typedef struct {
+  TUD_EPBUF_DEF(epout, CFG_TUD_CDC_EP_BUFSIZE);
+  TUD_EPBUF_DEF(epin, CFG_TUD_CDC_EP_BUFSIZE);
+} cdcd_epbuf_t;
+
 //--------------------------------------------------------------------+
 // INTERNAL OBJECT & FUNCTION DECLARATION
 //--------------------------------------------------------------------+
-CFG_TUD_MEM_SECTION tu_static cdcd_interface_t _cdcd_itf[CFG_TUD_CDC];
+static cdcd_interface_t _cdcd_itf[CFG_TUD_CDC];
+CFG_TUD_MEM_SECTION static cdcd_epbuf_t _cdcd_epbuf[CFG_TUD_CDC];
+
+static tud_cdc_configure_t _cdcd_cfg = TUD_CDC_CONFIGURE_DEFAULT();
+
+static bool _prep_out_transaction(uint8_t itf) {
+  const uint8_t rhport = 0;
+  cdcd_interface_t* p_cdc = &_cdcd_itf[itf];
+  cdcd_epbuf_t* p_epbuf = &_cdcd_epbuf[itf];
+
+  // Skip if usb is not ready yet
+  TU_VERIFY(tud_ready() && p_cdc->ep_out);
 
-static bool _prep_out_transaction (cdcd_interface_t* p_cdc)
-{
-  uint8_t const rhport = 0;
   uint16_t available = tu_fifo_remaining(&p_cdc->rx_ff);
 
   // Prepare for incoming data but only allow what we can store in the ring buffer.
   // TODO Actually we can still carry out the transfer, keeping count of received bytes
   // and slowly move it to the FIFO when read().
   // This pre-check reduces endpoint claiming
-  TU_VERIFY(available >= sizeof(p_cdc->epout_buf));
+  TU_VERIFY(available >= CFG_TUD_CDC_EP_BUFSIZE);
 
   // claim endpoint
   TU_VERIFY(usbd_edpt_claim(rhport, p_cdc->ep_out));
@@ -103,14 +106,11 @@ static bool _prep_out_transaction (cdcd_interface_t* p_cdc)
   // fifo can be changed before endpoint is claimed
   available = tu_fifo_remaining(&p_cdc->rx_ff);
 
-  if ( available >= sizeof(p_cdc->epout_buf) )
-  {
-    return usbd_edpt_xfer(rhport, p_cdc->ep_out, p_cdc->epout_buf, sizeof(p_cdc->epout_buf));
-  }else
-  {
+  if (available >= CFG_TUD_CDC_EP_BUFSIZE) {
+    return usbd_edpt_xfer(rhport, p_cdc->ep_out, p_epbuf->epout, CFG_TUD_CDC_EP_BUFSIZE);
+  } else {
     // Release endpoint since we don't make any transfer
     usbd_edpt_release(rhport, p_cdc->ep_out);
-
     return false;
   }
 }
@@ -118,99 +118,101 @@ static bool _prep_out_transaction (cdcd_interface_t* p_cdc)
 //--------------------------------------------------------------------+
 // APPLICATION API
 //--------------------------------------------------------------------+
-bool tud_cdc_n_connected(uint8_t itf)
-{
+
+bool tud_cdc_configure(const tud_cdc_configure_t* driver_cfg) {
+  TU_VERIFY(driver_cfg);
+  _cdcd_cfg = *driver_cfg;
+  return true;
+}
+
+bool tud_cdc_n_ready(uint8_t itf) {
+  return tud_ready() && _cdcd_itf[itf].ep_in != 0 && _cdcd_itf[itf].ep_out != 0;
+}
+
+bool tud_cdc_n_connected(uint8_t itf) {
   // DTR (bit 0) active  is considered as connected
   return tud_ready() && tu_bit_test(_cdcd_itf[itf].line_state, 0);
 }
 
-uint8_t tud_cdc_n_get_line_state (uint8_t itf)
-// TODO use cdc_line_control_state_t instead of uint8_t
-{
+uint8_t tud_cdc_n_get_line_state(uint8_t itf) {
   return _cdcd_itf[itf].line_state;
 }
 
-void tud_cdc_n_get_line_coding (uint8_t itf, cdc_line_coding_t* coding)
-{
+void tud_cdc_n_get_line_coding(uint8_t itf, cdc_line_coding_t* coding) {
   (*coding) = _cdcd_itf[itf].line_coding;
 }
 
-void tud_cdc_n_set_wanted_char (uint8_t itf, char wanted)
-{
+void tud_cdc_n_set_wanted_char(uint8_t itf, char wanted) {
   _cdcd_itf[itf].wanted_char = wanted;
 }
 
-
 //--------------------------------------------------------------------+
 // READ API
 //--------------------------------------------------------------------+
-uint32_t tud_cdc_n_available(uint8_t itf)
-{
+uint32_t tud_cdc_n_available(uint8_t itf) {
   return tu_fifo_count(&_cdcd_itf[itf].rx_ff);
 }
 
-uint32_t tud_cdc_n_read(uint8_t itf, void* buffer, uint32_t bufsize)
-{
+uint32_t tud_cdc_n_read(uint8_t itf, void* buffer, uint32_t bufsize) {
   cdcd_interface_t* p_cdc = &_cdcd_itf[itf];
   uint32_t num_read = tu_fifo_read_n(&p_cdc->rx_ff, buffer, (uint16_t) TU_MIN(bufsize, UINT16_MAX));
-  _prep_out_transaction(p_cdc);
+  _prep_out_transaction(itf);
   return num_read;
 }
 
-bool tud_cdc_n_peek(uint8_t itf, uint8_t* chr)
-{
+bool tud_cdc_n_peek(uint8_t itf, uint8_t* chr) {
   return tu_fifo_peek(&_cdcd_itf[itf].rx_ff, chr);
 }
 
-void tud_cdc_n_read_flush (uint8_t itf)
-{
+void tud_cdc_n_read_flush(uint8_t itf) {
   cdcd_interface_t* p_cdc = &_cdcd_itf[itf];
   tu_fifo_clear(&p_cdc->rx_ff);
-  _prep_out_transaction(p_cdc);
+  _prep_out_transaction(itf);
 }
 
 //--------------------------------------------------------------------+
 // WRITE API
 //--------------------------------------------------------------------+
-uint32_t tud_cdc_n_write(uint8_t itf, void const* buffer, uint32_t bufsize)
-{
+uint32_t tud_cdc_n_write(uint8_t itf, const void* buffer, uint32_t bufsize) {
   cdcd_interface_t* p_cdc = &_cdcd_itf[itf];
-  uint16_t ret = tu_fifo_write_n(&p_cdc->tx_ff, buffer, (uint16_t) TU_MIN(bufsize, UINT16_MAX));
+  uint16_t wr_count = tu_fifo_write_n(&p_cdc->tx_ff, buffer, (uint16_t) TU_MIN(bufsize, UINT16_MAX));
 
   // flush if queue more than packet size
-  // may need to suppress -Wunreachable-code since most of the time CFG_TUD_CDC_TX_BUFSIZE < BULK_PACKET_SIZE
-  if ( (tu_fifo_count(&p_cdc->tx_ff) >= BULK_PACKET_SIZE) || ((CFG_TUD_CDC_TX_BUFSIZE < BULK_PACKET_SIZE) && tu_fifo_full(&p_cdc->tx_ff)) )
-  {
+  if (tu_fifo_count(&p_cdc->tx_ff) >= BULK_PACKET_SIZE
+      #if CFG_TUD_CDC_TX_BUFSIZE < BULK_PACKET_SIZE
+      || tu_fifo_full(&p_cdc->tx_ff) // check full if fifo size is less than packet size
+      #endif
+      ) {
     tud_cdc_n_write_flush(itf);
   }
 
-  return ret;
+  return wr_count;
 }
 
-uint32_t tud_cdc_n_write_flush (uint8_t itf)
-{
+uint32_t tud_cdc_n_write_flush(uint8_t itf) {
   cdcd_interface_t* p_cdc = &_cdcd_itf[itf];
+  cdcd_epbuf_t* p_epbuf = &_cdcd_epbuf[itf];
 
   // Skip if usb is not ready yet
-  TU_VERIFY( tud_ready(), 0 );
+  TU_VERIFY(tud_ready(), 0);
 
   // No data to send
-  if ( !tu_fifo_count(&p_cdc->tx_ff) ) return 0;
+  if (!tu_fifo_count(&p_cdc->tx_ff)) {
+    return 0;
+  }
 
-  uint8_t const rhport = 0;
+  const uint8_t rhport = 0;
 
   // Claim the endpoint
-  TU_VERIFY( usbd_edpt_claim(rhport, p_cdc->ep_in), 0 );
+  TU_VERIFY(usbd_edpt_claim(rhport, p_cdc->ep_in), 0);
 
   // Pull data from FIFO
-  uint16_t const count = tu_fifo_read_n(&p_cdc->tx_ff, p_cdc->epin_buf, sizeof(p_cdc->epin_buf));
+  const uint16_t count = tu_fifo_read_n(&p_cdc->tx_ff, p_epbuf->epin, CFG_TUD_CDC_EP_BUFSIZE);
 
-  if ( count )
-  {
-    TU_ASSERT( usbd_edpt_xfer(rhport, p_cdc->ep_in, p_cdc->epin_buf, count), 0 );
+  if (count) {
+    TU_ASSERT(usbd_edpt_xfer(rhport, p_cdc->ep_in, p_epbuf->epin, count), 0);
     return count;
-  }else
-  {
+  } else {
     // Release endpoint since we don't make any transfer
     // Note: data is dropped if terminal is not connected
     usbd_edpt_release(rhport, p_cdc->ep_in);
@@ -218,122 +220,142 @@ uint32_t tud_cdc_n_write_flush (uint8_t itf)
   }
 }
 
-uint32_t tud_cdc_n_write_available (uint8_t itf)
-{
+uint32_t tud_cdc_n_write_available(uint8_t itf) {
   return tu_fifo_remaining(&_cdcd_itf[itf].tx_ff);
 }
 
-bool tud_cdc_n_write_clear (uint8_t itf)
-{
+bool tud_cdc_n_write_clear(uint8_t itf) {
   return tu_fifo_clear(&_cdcd_itf[itf].tx_ff);
 }
 
 //--------------------------------------------------------------------+
 // USBD Driver API
 //--------------------------------------------------------------------+
-void cdcd_init(void)
-{
+void cdcd_init(void) {
   tu_memclr(_cdcd_itf, sizeof(_cdcd_itf));
-
-  for(uint8_t i=0; i<CFG_TUD_CDC; i++)
-  {
+  for (uint8_t i = 0; i < CFG_TUD_CDC; i++) {
     cdcd_interface_t* p_cdc = &_cdcd_itf[i];
 
     p_cdc->wanted_char = (char) -1;
 
     // default line coding is : stop bit = 1, parity = none, data bits = 8
-    p_cdc->line_coding.bit_rate  = 115200;
+    p_cdc->line_coding.bit_rate = 115200;
     p_cdc->line_coding.stop_bits = 0;
-    p_cdc->line_coding.parity    = 0;
+    p_cdc->line_coding.parity = 0;
     p_cdc->line_coding.data_bits = 8;
 
     // Config RX fifo
     tu_fifo_config(&p_cdc->rx_ff, p_cdc->rx_ff_buf, TU_ARRAY_SIZE(p_cdc->rx_ff_buf), 1, false);
 
-    // Config TX fifo as overwritable at initialization and will be changed to non-overwritable
-    // if terminal supports DTR bit. Without DTR we do not know if data is actually polled by terminal.
-    // In this way, the most current data is prioritized.
-    tu_fifo_config(&p_cdc->tx_ff, p_cdc->tx_ff_buf, TU_ARRAY_SIZE(p_cdc->tx_ff_buf), 1, true);
+    // TX fifo can be configured to change to overwritable if not connected (DTR bit not set). Without DTR we do not
+    // know if data is actually polled by terminal. This way the most current data is prioritized.
+    // Default: is overwritable
+    tu_fifo_config(&p_cdc->tx_ff, p_cdc->tx_ff_buf, TU_ARRAY_SIZE(p_cdc->tx_ff_buf), 1, _cdcd_cfg.tx_overwritabe_if_not_connected);
+
+    #if OSAL_MUTEX_REQUIRED
+    osal_mutex_t mutex_rd = osal_mutex_create(&p_cdc->rx_ff_mutex);
+    osal_mutex_t mutex_wr = osal_mutex_create(&p_cdc->tx_ff_mutex);
+    TU_ASSERT(mutex_rd != NULL && mutex_wr != NULL, );
 
-    tu_fifo_config_mutex(&p_cdc->rx_ff, NULL, osal_mutex_create(&p_cdc->rx_ff_mutex));
-    tu_fifo_config_mutex(&p_cdc->tx_ff, osal_mutex_create(&p_cdc->tx_ff_mutex), NULL);
+    tu_fifo_config_mutex(&p_cdc->rx_ff, NULL, mutex_rd);
+    tu_fifo_config_mutex(&p_cdc->tx_ff, mutex_wr, NULL);
+    #endif
   }
 }
 
-void cdcd_reset(uint8_t rhport)
-{
+bool cdcd_deinit(void) {
+  #if OSAL_MUTEX_REQUIRED
+  for(uint8_t i=0; i<CFG_TUD_CDC; i++) {
+    cdcd_interface_t* p_cdc = &_cdcd_itf[i];
+    osal_mutex_t mutex_rd = p_cdc->rx_ff.mutex_rd;
+    osal_mutex_t mutex_wr = p_cdc->tx_ff.mutex_wr;
+
+    if (mutex_rd) {
+      osal_mutex_delete(mutex_rd);
+      tu_fifo_config_mutex(&p_cdc->rx_ff, NULL, NULL);
+    }
+
+    if (mutex_wr) {
+      osal_mutex_delete(mutex_wr);
+      tu_fifo_config_mutex(&p_cdc->tx_ff, NULL, NULL);
+    }
+  }
+  #endif
+
+  return true;
+}
+
+void cdcd_reset(uint8_t rhport) {
   (void) rhport;
 
-  for(uint8_t i=0; i<CFG_TUD_CDC; i++)
-  {
+  for (uint8_t i = 0; i < CFG_TUD_CDC; i++) {
     cdcd_interface_t* p_cdc = &_cdcd_itf[i];
 
     tu_memclr(p_cdc, ITF_MEM_RESET_SIZE);
-    tu_fifo_clear(&p_cdc->rx_ff);
-    tu_fifo_clear(&p_cdc->tx_ff);
-    tu_fifo_set_overwritable(&p_cdc->tx_ff, true);
+    if (!_cdcd_cfg.rx_persistent) {
+      tu_fifo_clear(&p_cdc->rx_ff);
+    }
+    if (!_cdcd_cfg.tx_persistent) {
+      tu_fifo_clear(&p_cdc->tx_ff);
+    }
+    tu_fifo_set_overwritable(&p_cdc->tx_ff, _cdcd_cfg.tx_overwritabe_if_not_connected);
   }
 }
 
-uint16_t cdcd_open(uint8_t rhport, tusb_desc_interface_t const * itf_desc, uint16_t max_len)
-{
+uint16_t cdcd_open(uint8_t rhport, const tusb_desc_interface_t* itf_desc, uint16_t max_len) {
   // Only support ACM subclass
   TU_VERIFY( TUSB_CLASS_CDC                           == itf_desc->bInterfaceClass &&
              CDC_COMM_SUBCLASS_ABSTRACT_CONTROL_MODEL == itf_desc->bInterfaceSubClass, 0);
 
   // Find available interface
-  cdcd_interface_t * p_cdc = NULL;
-  for(uint8_t cdc_id=0; cdc_id<CFG_TUD_CDC; cdc_id++)
-  {
-    if ( _cdcd_itf[cdc_id].ep_in == 0 )
-    {
-      p_cdc = &_cdcd_itf[cdc_id];
+  cdcd_interface_t* p_cdc;
+  uint8_t cdc_id;
+  for (cdc_id = 0; cdc_id < CFG_TUD_CDC; cdc_id++) {
+    p_cdc = &_cdcd_itf[cdc_id];
+    if (p_cdc->ep_in == 0) {
       break;
     }
   }
-  TU_ASSERT(p_cdc, 0);
+  TU_ASSERT(cdc_id < CFG_TUD_CDC, 0);
 
   //------------- Control Interface -------------//
   p_cdc->itf_num = itf_desc->bInterfaceNumber;
 
   uint16_t drv_len = sizeof(tusb_desc_interface_t);
-  uint8_t const * p_desc = tu_desc_next( itf_desc );
+  const uint8_t* p_desc = tu_desc_next(itf_desc);
 
   // Communication Functional Descriptors
-  while ( TUSB_DESC_CS_INTERFACE == tu_desc_type(p_desc) && drv_len <= max_len )
-  {
+  while (TUSB_DESC_CS_INTERFACE == tu_desc_type(p_desc) && drv_len <= max_len) {
     drv_len += tu_desc_len(p_desc);
-    p_desc   = tu_desc_next(p_desc);
+    p_desc = tu_desc_next(p_desc);
   }
 
-  if ( TUSB_DESC_ENDPOINT == tu_desc_type(p_desc) )
-  {
+  if (TUSB_DESC_ENDPOINT == tu_desc_type(p_desc)) {
     // notification endpoint
-    tusb_desc_endpoint_t const * desc_ep = (tusb_desc_endpoint_t const *) p_desc;
+    const tusb_desc_endpoint_t* desc_ep = (const tusb_desc_endpoint_t*) p_desc;
 
-    TU_ASSERT( usbd_edpt_open(rhport, desc_ep), 0 );
+    TU_ASSERT(usbd_edpt_open(rhport, desc_ep), 0);
     p_cdc->ep_notif = desc_ep->bEndpointAddress;
 
     drv_len += tu_desc_len(p_desc);
-    p_desc   = tu_desc_next(p_desc);
+    p_desc = tu_desc_next(p_desc);
   }
 
   //------------- Data Interface (if any) -------------//
-  if ( (TUSB_DESC_INTERFACE == tu_desc_type(p_desc)) &&
-       (TUSB_CLASS_CDC_DATA == ((tusb_desc_interface_t const *) p_desc)->bInterfaceClass) )
-  {
+  if ((TUSB_DESC_INTERFACE == tu_desc_type(p_desc)) &&
+      (TUSB_CLASS_CDC_DATA == ((const tusb_desc_interface_t*) p_desc)->bInterfaceClass)) {
     // next to endpoint descriptor
     drv_len += tu_desc_len(p_desc);
-    p_desc   = tu_desc_next(p_desc);
+    p_desc = tu_desc_next(p_desc);
 
     // Open endpoint pair
-    TU_ASSERT( usbd_open_edpt_pair(rhport, p_desc, 2, TUSB_XFER_BULK, &p_cdc->ep_out, &p_cdc->ep_in), 0 );
+    TU_ASSERT(usbd_open_edpt_pair(rhport, p_desc, 2, TUSB_XFER_BULK, &p_cdc->ep_out, &p_cdc->ep_in), 0);
 
-    drv_len += 2*sizeof(tusb_desc_endpoint_t);
+    drv_len += 2 * sizeof(tusb_desc_endpoint_t);
   }
 
   // Prepare for incoming data
-  _prep_out_transaction(p_cdc);
+  _prep_out_transaction(cdc_id);
 
   return drv_len;
 }
@@ -341,51 +363,45 @@ uint16_t cdcd_open(uint8_t rhport, tusb_desc_interface_t const * itf_desc, uint1
 // Invoked when a control transfer occurred on an interface of this class
 // Driver response accordingly to the request and the transfer stage (setup/data/ack)
 // return false to stall control endpoint (e.g unsupported request)
-bool cdcd_control_xfer_cb(uint8_t rhport, uint8_t stage, tusb_control_request_t const * request)
-{
+bool cdcd_control_xfer_cb(uint8_t rhport, uint8_t stage, const tusb_control_request_t* request) {
   // Handle class request only
   TU_VERIFY(request->bmRequestType_bit.type == TUSB_REQ_TYPE_CLASS);
 
-  uint8_t itf = 0;
-  cdcd_interface_t* p_cdc = _cdcd_itf;
+  uint8_t itf;
+  cdcd_interface_t* p_cdc;
 
   // Identify which interface to use
-  for ( ; ; itf++, p_cdc++)
-  {
-    if (itf >= TU_ARRAY_SIZE(_cdcd_itf)) return false;
-
-    if ( p_cdc->itf_num == request->wIndex ) break;
+  for (itf = 0; itf < CFG_TUD_CDC; itf++) {
+    p_cdc = &_cdcd_itf[itf];
+    if (p_cdc->itf_num == request->wIndex) {
+      break;
+    }
   }
+  TU_VERIFY(itf < CFG_TUD_CDC);
 
-  switch ( request->bRequest )
-  {
+  switch (request->bRequest) {
     case CDC_REQUEST_SET_LINE_CODING:
-      if (stage == CONTROL_STAGE_SETUP)
-      {
+      if (stage == CONTROL_STAGE_SETUP) {
         TU_LOG_DRV("  Set Line Coding\r\n");
         tud_control_xfer(rhport, request, &p_cdc->line_coding, sizeof(cdc_line_coding_t));
+      } else if (stage == CONTROL_STAGE_ACK) {
+        if (tud_cdc_line_coding_cb) {
+          tud_cdc_line_coding_cb(itf, &p_cdc->line_coding);
+        }
       }
-      else if ( stage == CONTROL_STAGE_ACK)
-      {
-        if ( tud_cdc_line_coding_cb ) tud_cdc_line_coding_cb(itf, &p_cdc->line_coding);
-      }
-    break;
+      break;
 
     case CDC_REQUEST_GET_LINE_CODING:
-      if (stage == CONTROL_STAGE_SETUP)
-      {
+      if (stage == CONTROL_STAGE_SETUP) {
         TU_LOG_DRV("  Get Line Coding\r\n");
         tud_control_xfer(rhport, request, &p_cdc->line_coding, sizeof(cdc_line_coding_t));
       }
-    break;
+      break;
 
     case CDC_REQUEST_SET_CONTROL_LINE_STATE:
-      if (stage == CONTROL_STAGE_SETUP)
-      {
+      if (stage == CONTROL_STAGE_SETUP) {
         tud_control_status(rhport, request);
-      }
-      else if (stage == CONTROL_STAGE_ACK)
-      {
+      } else if (stage == CONTROL_STAGE_ACK) {
         // CDC PSTN v1.2 section 6.3.12
         // Bit 0: Indicates if DTE is present or not.
         //        This signal corresponds to V.24 signal 108/2 and RS-232 signal DTR (Data Terminal Ready)
@@ -396,89 +412,93 @@ bool cdcd_control_xfer_cb(uint8_t rhport, uint8_t stage, tusb_control_request_t
 
         p_cdc->line_state = (uint8_t) request->wValue;
 
-        // Disable fifo overwriting if DTR bit is set
-        tu_fifo_set_overwritable(&p_cdc->tx_ff, !dtr);
+        // If enabled: fifo overwriting is disabled if DTR bit is set and vice versa
+        if (_cdcd_cfg.tx_overwritabe_if_not_connected) {
+          tu_fifo_set_overwritable(&p_cdc->tx_ff, !dtr);
+        } else {
+          tu_fifo_set_overwritable(&p_cdc->tx_ff, false);
+        }
 
         TU_LOG_DRV("  Set Control Line State: DTR = %d, RTS = %d\r\n", dtr, rts);
 
         // Invoke callback
-        if ( tud_cdc_line_state_cb ) tud_cdc_line_state_cb(itf, dtr, rts);
+        if (tud_cdc_line_state_cb) {
+          tud_cdc_line_state_cb(itf, dtr, rts);
+        }
       }
-    break;
+      break;
+
     case CDC_REQUEST_SEND_BREAK:
-      if (stage == CONTROL_STAGE_SETUP)
-      {
+      if (stage == CONTROL_STAGE_SETUP) {
         tud_control_status(rhport, request);
-      }
-      else if (stage == CONTROL_STAGE_ACK)
-      {
+      } else if (stage == CONTROL_STAGE_ACK) {
         TU_LOG_DRV("  Send Break\r\n");
-        if ( tud_cdc_send_break_cb ) tud_cdc_send_break_cb(itf, request->wValue);
+        if (tud_cdc_send_break_cb) {
+          tud_cdc_send_break_cb(itf, request->wValue);
+        }
       }
-    break;
+      break;
 
-    default: return false; // stall unsupported request
+    default:
+      return false; // stall unsupported request
   }
 
   return true;
 }
 
-bool cdcd_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint32_t xferred_bytes)
-{
+bool cdcd_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint32_t xferred_bytes) {
   (void) result;
 
   uint8_t itf;
   cdcd_interface_t* p_cdc;
 
   // Identify which interface to use
-  for (itf = 0; itf < CFG_TUD_CDC; itf++)
-  {
+  for (itf = 0; itf < CFG_TUD_CDC; itf++) {
     p_cdc = &_cdcd_itf[itf];
-    if ( ( ep_addr == p_cdc->ep_out ) || ( ep_addr == p_cdc->ep_in ) ) break;
+    if ((ep_addr == p_cdc->ep_out) || (ep_addr == p_cdc->ep_in)) {
+      break;
+    }
   }
   TU_ASSERT(itf < CFG_TUD_CDC);
+  cdcd_epbuf_t* p_epbuf = &_cdcd_epbuf[itf];
 
   // Received new data
-  if ( ep_addr == p_cdc->ep_out )
-  {
-    tu_fifo_write_n(&p_cdc->rx_ff, p_cdc->epout_buf, (uint16_t) xferred_bytes);
+  if (ep_addr == p_cdc->ep_out) {
+    tu_fifo_write_n(&p_cdc->rx_ff, p_epbuf->epout, (uint16_t) xferred_bytes);
 
     // Check for wanted char and invoke callback if needed
-    if ( tud_cdc_rx_wanted_cb && (((signed char) p_cdc->wanted_char) != -1) )
-    {
-      for ( uint32_t i = 0; i < xferred_bytes; i++ )
-      {
-        if ( (p_cdc->wanted_char == p_cdc->epout_buf[i]) && !tu_fifo_empty(&p_cdc->rx_ff) )
-        {
+    if (tud_cdc_rx_wanted_cb && (((signed char) p_cdc->wanted_char) != -1)) {
+      for (uint32_t i = 0; i < xferred_bytes; i++) {
+        if ((p_cdc->wanted_char == p_epbuf->epout[i]) && !tu_fifo_empty(&p_cdc->rx_ff)) {
           tud_cdc_rx_wanted_cb(itf, p_cdc->wanted_char);
         }
       }
     }
 
     // invoke receive callback (if there is still data)
-    if (tud_cdc_rx_cb && !tu_fifo_empty(&p_cdc->rx_ff) ) tud_cdc_rx_cb(itf);
+    if (tud_cdc_rx_cb && !tu_fifo_empty(&p_cdc->rx_ff)) {
+      tud_cdc_rx_cb(itf);
+    }
 
     // prepare for OUT transaction
-    _prep_out_transaction(p_cdc);
+    _prep_out_transaction(itf);
   }
 
   // Data sent to host, we continue to fetch from tx fifo to send.
   // Note: This will cause incorrect baudrate set in line coding.
   //       Though maybe the baudrate is not really important !!!
-  if ( ep_addr == p_cdc->ep_in )
-  {
+  if (ep_addr == p_cdc->ep_in) {
     // invoke transmit callback to possibly refill tx fifo
-    if ( tud_cdc_tx_complete_cb ) tud_cdc_tx_complete_cb(itf);
+    if (tud_cdc_tx_complete_cb) {
+      tud_cdc_tx_complete_cb(itf);
+    }
 
-    if ( 0 == tud_cdc_n_write_flush(itf) )
-    {
+    if (0 == tud_cdc_n_write_flush(itf)) {
       // If there is no data left, a ZLP should be sent if
       // xferred_bytes is multiple of EP Packet size and not zero
-      if ( !tu_fifo_count(&p_cdc->tx_ff) && xferred_bytes && (0 == (xferred_bytes & (BULK_PACKET_SIZE-1))) )
-      {
-        if ( usbd_edpt_claim(rhport, p_cdc->ep_in) )
-        {
-          usbd_edpt_xfer(rhport, p_cdc->ep_in, NULL, 0);
+      if (!tu_fifo_count(&p_cdc->tx_ff) && xferred_bytes && (0 == (xferred_bytes & (BULK_PACKET_SIZE - 1)))) {
+        if (usbd_edpt_claim(rhport, p_cdc->ep_in)) {
+          TU_ASSERT(usbd_edpt_xfer(rhport, p_cdc->ep_in, NULL, 0));
         }
       }
     }
diff --git a/src/class/cdc/cdc_device.h b/src/class/cdc/cdc_device.h
index a6e07aa5c..b653ebd74 100644
--- a/src/class/cdc/cdc_device.h
+++ b/src/class/cdc/cdc_device.h
@@ -24,8 +24,8 @@
  * This file is part of the TinyUSB stack.
  */
 
-#ifndef _TUSB_CDC_DEVICE_H_
-#define _TUSB_CDC_DEVICE_H_
+#ifndef TUSB_CDC_DEVICE_H_
+#define TUSB_CDC_DEVICE_H_
 
 #include "cdc.h"
 
@@ -45,208 +45,185 @@
  extern "C" {
 #endif
 
-/** \addtogroup CDC_Serial Serial
- *  @{
- *  \defgroup   CDC_Serial_Device Device
- *  @{ */
+//--------------------------------------------------------------------+
+// Driver Configuration
+//--------------------------------------------------------------------+
+typedef struct TU_ATTR_PACKED {
+  uint8_t rx_persistent : 1; // keep rx fifo data even with bus reset or disconnect
+  uint8_t tx_persistent : 1; // keep tx fifo data even with reset or disconnect
+  uint8_t tx_overwritabe_if_not_connected : 1; // if not connected, tx fifo can be overwritten
+} tud_cdc_configure_t;
+
+#define TUD_CDC_CONFIGURE_DEFAULT() { \
+  .rx_persistent = 0, \
+  .tx_persistent = 0, \
+  .tx_overwritabe_if_not_connected = 1, \
+}
+
+// Configure CDC driver behavior
+bool tud_cdc_configure(const tud_cdc_configure_t* driver_cfg);
+
+// Backward compatible
+#define tud_cdc_configure_fifo_t tud_cdc_configure_t
+#define tud_cdc_configure_fifo   tud_cdc_configure
 
 //--------------------------------------------------------------------+
-// Application API (Multiple Ports)
-// CFG_TUD_CDC > 1
+// Application API (Multiple Ports) i.e. CFG_TUD_CDC > 1
 //--------------------------------------------------------------------+
 
+// Check if interface is ready
+bool tud_cdc_n_ready(uint8_t itf);
+
 // Check if terminal is connected to this port
-bool     tud_cdc_n_connected       (uint8_t itf);
+bool tud_cdc_n_connected(uint8_t itf);
 
 // Get current line state. Bit 0:  DTR (Data Terminal Ready), Bit 1: RTS (Request to Send)
-uint8_t  tud_cdc_n_get_line_state  (uint8_t itf);
+uint8_t tud_cdc_n_get_line_state(uint8_t itf);
 
 // Get current line encoding: bit rate, stop bits parity etc ..
-void     tud_cdc_n_get_line_coding (uint8_t itf, cdc_line_coding_t* coding);
+void tud_cdc_n_get_line_coding(uint8_t itf, cdc_line_coding_t* coding);
 
 // Set special character that will trigger tud_cdc_rx_wanted_cb() callback on receiving
-void     tud_cdc_n_set_wanted_char (uint8_t itf, char wanted);
+void tud_cdc_n_set_wanted_char(uint8_t itf, char wanted);
 
 // Get the number of bytes available for reading
-uint32_t tud_cdc_n_available       (uint8_t itf);
+uint32_t tud_cdc_n_available(uint8_t itf);
 
 // Read received bytes
-uint32_t tud_cdc_n_read            (uint8_t itf, void* buffer, uint32_t bufsize);
+uint32_t tud_cdc_n_read(uint8_t itf, void* buffer, uint32_t bufsize);
 
 // Read a byte, return -1 if there is none
-static inline
-int32_t  tud_cdc_n_read_char       (uint8_t itf);
+TU_ATTR_ALWAYS_INLINE static inline int32_t tud_cdc_n_read_char(uint8_t itf) {
+  uint8_t ch;
+  return tud_cdc_n_read(itf, &ch, 1) ? (int32_t) ch : -1;
+}
 
 // Clear the received FIFO
-void     tud_cdc_n_read_flush      (uint8_t itf);
+void tud_cdc_n_read_flush(uint8_t itf);
 
 // Get a byte from FIFO without removing it
-bool     tud_cdc_n_peek            (uint8_t itf, uint8_t* ui8);
+bool tud_cdc_n_peek(uint8_t itf, uint8_t* ui8);
 
 // Write bytes to TX FIFO, data may remain in the FIFO for a while
-uint32_t tud_cdc_n_write           (uint8_t itf, void const* buffer, uint32_t bufsize);
+uint32_t tud_cdc_n_write(uint8_t itf, void const* buffer, uint32_t bufsize);
 
 // Write a byte
-static inline
-uint32_t tud_cdc_n_write_char      (uint8_t itf, char ch);
+TU_ATTR_ALWAYS_INLINE static inline uint32_t tud_cdc_n_write_char(uint8_t itf, char ch) {
+  return tud_cdc_n_write(itf, &ch, 1);
+}
 
 // Write a null-terminated string
-static inline
-uint32_t tud_cdc_n_write_str       (uint8_t itf, char const* str);
+TU_ATTR_ALWAYS_INLINE static inline uint32_t tud_cdc_n_write_str(uint8_t itf, char const* str) {
+  return tud_cdc_n_write(itf, str, strlen(str));
+}
 
 // Force sending data if possible, return number of forced bytes
-uint32_t tud_cdc_n_write_flush     (uint8_t itf);
+uint32_t tud_cdc_n_write_flush(uint8_t itf);
 
 // Return the number of bytes (characters) available for writing to TX FIFO buffer in a single n_write operation.
-uint32_t tud_cdc_n_write_available (uint8_t itf);
+uint32_t tud_cdc_n_write_available(uint8_t itf);
 
 // Clear the transmit FIFO
-bool tud_cdc_n_write_clear (uint8_t itf);
+bool tud_cdc_n_write_clear(uint8_t itf);
 
 //--------------------------------------------------------------------+
 // Application API (Single Port)
 //--------------------------------------------------------------------+
-static inline bool     tud_cdc_connected       (void);
-static inline uint8_t  tud_cdc_get_line_state  (void);
-static inline void     tud_cdc_get_line_coding (cdc_line_coding_t* coding);
-static inline void     tud_cdc_set_wanted_char (char wanted);
-
-static inline uint32_t tud_cdc_available       (void);
-static inline int32_t  tud_cdc_read_char       (void);
-static inline uint32_t tud_cdc_read            (void* buffer, uint32_t bufsize);
-static inline void     tud_cdc_read_flush      (void);
-static inline bool     tud_cdc_peek            (uint8_t* ui8);
-
-static inline uint32_t tud_cdc_write_char      (char ch);
-static inline uint32_t tud_cdc_write           (void const* buffer, uint32_t bufsize);
-static inline uint32_t tud_cdc_write_str       (char const* str);
-static inline uint32_t tud_cdc_write_flush     (void);
-static inline uint32_t tud_cdc_write_available (void);
-static inline bool     tud_cdc_write_clear     (void);
-
-//--------------------------------------------------------------------+
-// Application Callback API (weak is optional)
-//--------------------------------------------------------------------+
-
-// Invoked when received new data
-TU_ATTR_WEAK void tud_cdc_rx_cb(uint8_t itf);
-
-// Invoked when received `wanted_char`
-TU_ATTR_WEAK void tud_cdc_rx_wanted_cb(uint8_t itf, char wanted_char);
-
-// Invoked when a TX is complete and therefore space becomes available in TX buffer
-TU_ATTR_WEAK void tud_cdc_tx_complete_cb(uint8_t itf);
-
-// Invoked when line state DTR & RTS are changed via SET_CONTROL_LINE_STATE
-TU_ATTR_WEAK void tud_cdc_line_state_cb(uint8_t itf, bool dtr, bool rts);
-
-// Invoked when line coding is change via SET_LINE_CODING
-TU_ATTR_WEAK void tud_cdc_line_coding_cb(uint8_t itf, cdc_line_coding_t const* p_line_coding);
 
-// Invoked when received send break
-TU_ATTR_WEAK void tud_cdc_send_break_cb(uint8_t itf, uint16_t duration_ms);
-
-//--------------------------------------------------------------------+
-// Inline Functions
-//--------------------------------------------------------------------+
-static inline int32_t tud_cdc_n_read_char (uint8_t itf)
-{
-  uint8_t ch;
-  return tud_cdc_n_read(itf, &ch, 1) ? (int32_t) ch : -1;
+TU_ATTR_ALWAYS_INLINE static inline bool tud_cdc_ready(void) {
+  return tud_cdc_n_ready(0);
 }
 
-static inline uint32_t tud_cdc_n_write_char(uint8_t itf, char ch)
-{
-  return tud_cdc_n_write(itf, &ch, 1);
-}
-
-static inline uint32_t tud_cdc_n_write_str (uint8_t itf, char const* str)
-{
-  return tud_cdc_n_write(itf, str, strlen(str));
-}
-
-static inline bool tud_cdc_connected (void)
-{
+TU_ATTR_ALWAYS_INLINE static inline bool tud_cdc_connected(void) {
   return tud_cdc_n_connected(0);
 }
 
-static inline uint8_t tud_cdc_get_line_state (void)
-{
+TU_ATTR_ALWAYS_INLINE static inline uint8_t tud_cdc_get_line_state(void) {
   return tud_cdc_n_get_line_state(0);
 }
 
-static inline void tud_cdc_get_line_coding (cdc_line_coding_t* coding)
-{
+TU_ATTR_ALWAYS_INLINE static inline void tud_cdc_get_line_coding(cdc_line_coding_t* coding) {
   tud_cdc_n_get_line_coding(0, coding);
 }
 
-static inline void tud_cdc_set_wanted_char (char wanted)
-{
+TU_ATTR_ALWAYS_INLINE static inline void tud_cdc_set_wanted_char(char wanted) {
   tud_cdc_n_set_wanted_char(0, wanted);
 }
 
-static inline uint32_t tud_cdc_available (void)
-{
+TU_ATTR_ALWAYS_INLINE static inline uint32_t tud_cdc_available(void) {
   return tud_cdc_n_available(0);
 }
 
-static inline int32_t tud_cdc_read_char (void)
-{
+TU_ATTR_ALWAYS_INLINE static inline int32_t tud_cdc_read_char(void) {
   return tud_cdc_n_read_char(0);
 }
 
-static inline uint32_t tud_cdc_read (void* buffer, uint32_t bufsize)
-{
+TU_ATTR_ALWAYS_INLINE static inline uint32_t tud_cdc_read(void* buffer, uint32_t bufsize) {
   return tud_cdc_n_read(0, buffer, bufsize);
 }
 
-static inline void tud_cdc_read_flush (void)
-{
+TU_ATTR_ALWAYS_INLINE static inline void tud_cdc_read_flush(void) {
   tud_cdc_n_read_flush(0);
 }
 
-static inline bool tud_cdc_peek (uint8_t* ui8)
-{
+TU_ATTR_ALWAYS_INLINE static inline bool tud_cdc_peek(uint8_t* ui8) {
   return tud_cdc_n_peek(0, ui8);
 }
 
-static inline uint32_t tud_cdc_write_char (char ch)
-{
+TU_ATTR_ALWAYS_INLINE static inline uint32_t tud_cdc_write_char(char ch) {
   return tud_cdc_n_write_char(0, ch);
 }
 
-static inline uint32_t tud_cdc_write (void const* buffer, uint32_t bufsize)
-{
+TU_ATTR_ALWAYS_INLINE static inline uint32_t tud_cdc_write(void const* buffer, uint32_t bufsize) {
   return tud_cdc_n_write(0, buffer, bufsize);
 }
 
-static inline uint32_t tud_cdc_write_str (char const* str)
-{
+TU_ATTR_ALWAYS_INLINE static inline uint32_t tud_cdc_write_str(char const* str) {
   return tud_cdc_n_write_str(0, str);
 }
 
-static inline uint32_t tud_cdc_write_flush (void)
-{
+TU_ATTR_ALWAYS_INLINE static inline uint32_t tud_cdc_write_flush(void) {
   return tud_cdc_n_write_flush(0);
 }
 
-static inline uint32_t tud_cdc_write_available(void)
-{
+TU_ATTR_ALWAYS_INLINE static inline uint32_t tud_cdc_write_available(void) {
   return tud_cdc_n_write_available(0);
 }
 
-static inline bool tud_cdc_write_clear(void)
-{
+TU_ATTR_ALWAYS_INLINE static inline bool tud_cdc_write_clear(void) {
   return tud_cdc_n_write_clear(0);
 }
 
-/** @} */
-/** @} */
+//--------------------------------------------------------------------+
+// Application Callback API (weak is optional)
+//--------------------------------------------------------------------+
+
+// Invoked when received new data
+TU_ATTR_WEAK void tud_cdc_rx_cb(uint8_t itf);
+
+// Invoked when received `wanted_char`
+TU_ATTR_WEAK void tud_cdc_rx_wanted_cb(uint8_t itf, char wanted_char);
+
+// Invoked when a TX is complete and therefore space becomes available in TX buffer
+TU_ATTR_WEAK void tud_cdc_tx_complete_cb(uint8_t itf);
+
+// Invoked when line state DTR & RTS are changed via SET_CONTROL_LINE_STATE
+TU_ATTR_WEAK void tud_cdc_line_state_cb(uint8_t itf, bool dtr, bool rts);
+
+// Invoked when line coding is change via SET_LINE_CODING
+TU_ATTR_WEAK void tud_cdc_line_coding_cb(uint8_t itf, cdc_line_coding_t const* p_line_coding);
+
+// Invoked when received send break
+// \param[in]  itf  interface for which send break was received.
+// \param[in]  duration_ms  the length of time, in milliseconds, of the break signal. If a value of FFFFh, then the
+//                          device will send a break until another SendBreak request is received with value 0000h.
+TU_ATTR_WEAK void tud_cdc_send_break_cb(uint8_t itf, uint16_t duration_ms);
 
 //--------------------------------------------------------------------+
 // INTERNAL USBD-CLASS DRIVER API
 //--------------------------------------------------------------------+
 void     cdcd_init            (void);
+bool     cdcd_deinit          (void);
 void     cdcd_reset           (uint8_t rhport);
 uint16_t cdcd_open            (uint8_t rhport, tusb_desc_interface_t const * itf_desc, uint16_t max_len);
 bool     cdcd_control_xfer_cb (uint8_t rhport, uint8_t stage, tusb_control_request_t const * request);
diff --git a/src/class/cdc/cdc_host.c b/src/class/cdc/cdc_host.c
index fbe0cc9ca..5d5da9796 100644
--- a/src/class/cdc/cdc_host.c
+++ b/src/class/cdc/cdc_host.c
@@ -122,15 +122,17 @@ typedef struct {
     tu_edpt_stream_t rx;
 
     uint8_t tx_ff_buf[CFG_TUH_CDC_TX_BUFSIZE];
-    CFG_TUH_MEM_ALIGN uint8_t tx_ep_buf[CFG_TUH_CDC_TX_EPSIZE];
-
     uint8_t rx_ff_buf[CFG_TUH_CDC_TX_BUFSIZE];
-    CFG_TUH_MEM_ALIGN uint8_t rx_ep_buf[CFG_TUH_CDC_TX_EPSIZE];
   } stream;
 } cdch_interface_t;
 
-CFG_TUH_MEM_SECTION
+typedef struct {
+  TUH_EPBUF_DEF(tx, CFG_TUH_CDC_TX_EPSIZE);
+  TUH_EPBUF_DEF(rx, CFG_TUH_CDC_TX_EPSIZE);
+} cdch_epbuf_t;
+
 static cdch_interface_t cdch_data[CFG_TUH_CDC];
+CFG_TUH_MEM_SECTION static cdch_epbuf_t cdch_epbuf[CFG_TUH_CDC];
 
 #if CFG_TUH_CDC_FTDI || CFG_TUH_CDC_PL2303
   static tusb_desc_device_t desc_dev[CFG_TUH_ENUMERATION_BUFSIZE];
@@ -451,14 +453,14 @@ uint32_t tuh_cdc_write(uint8_t idx, void const * buffer, uint32_t bufsize) {
   cdch_interface_t * p_cdc = get_itf(idx);
   TU_VERIFY(p_cdc);
 
-  return tu_edpt_stream_write(&p_cdc->stream.tx, buffer, bufsize);
+  return tu_edpt_stream_write(p_cdc->daddr, &p_cdc->stream.tx, buffer, bufsize);
 }
 
 uint32_t tuh_cdc_write_flush(uint8_t idx) {
   cdch_interface_t * p_cdc = get_itf(idx);
   TU_VERIFY(p_cdc);
 
-  return tu_edpt_stream_write_xfer(&p_cdc->stream.tx);
+  return tu_edpt_stream_write_xfer(p_cdc->daddr, &p_cdc->stream.tx);
 }
 
 bool tuh_cdc_write_clear(uint8_t idx) {
@@ -472,7 +474,7 @@ uint32_t tuh_cdc_write_available(uint8_t idx) {
   cdch_interface_t * p_cdc = get_itf(idx);
   TU_VERIFY(p_cdc);
 
-  return tu_edpt_stream_write_available(&p_cdc->stream.tx);
+  return tu_edpt_stream_write_available(p_cdc->daddr, &p_cdc->stream.tx);
 }
 
 //--------------------------------------------------------------------+
@@ -483,7 +485,7 @@ uint32_t tuh_cdc_read (uint8_t idx, void * buffer, uint32_t bufsize) {
   cdch_interface_t * p_cdc = get_itf(idx);
   TU_VERIFY(p_cdc);
 
-  return tu_edpt_stream_read(&p_cdc->stream.rx, buffer, bufsize);
+  return tu_edpt_stream_read(p_cdc->daddr, &p_cdc->stream.rx, buffer, bufsize);
 }
 
 uint32_t tuh_cdc_read_available(uint8_t idx) {
@@ -505,8 +507,7 @@ bool tuh_cdc_read_clear (uint8_t idx) {
   TU_VERIFY(p_cdc);
 
   bool ret = tu_edpt_stream_clear(&p_cdc->stream.rx);
-  tu_edpt_stream_read_xfer(&p_cdc->stream.rx);
-
+  tu_edpt_stream_read_xfer(p_cdc->daddr, &p_cdc->stream.rx);
   return ret;
 }
 
@@ -722,13 +723,14 @@ bool cdch_init(void) {
   tu_memclr(cdch_data, sizeof(cdch_data));
   for (size_t i = 0; i < CFG_TUH_CDC; i++) {
     cdch_interface_t* p_cdc = &cdch_data[i];
+    cdch_epbuf_t* epbuf = &cdch_epbuf[i];
     tu_edpt_stream_init(&p_cdc->stream.tx, true, true, false,
                         p_cdc->stream.tx_ff_buf, CFG_TUH_CDC_TX_BUFSIZE,
-                        p_cdc->stream.tx_ep_buf, CFG_TUH_CDC_TX_EPSIZE);
+                        epbuf->tx, CFG_TUH_CDC_TX_EPSIZE);
 
     tu_edpt_stream_init(&p_cdc->stream.rx, true, false, false,
                         p_cdc->stream.rx_ff_buf, CFG_TUH_CDC_RX_BUFSIZE,
-                        p_cdc->stream.rx_ep_buf, CFG_TUH_CDC_RX_EPSIZE);
+                        epbuf->rx, CFG_TUH_CDC_RX_EPSIZE);
   }
 
   return true;
@@ -750,7 +752,9 @@ void cdch_close(uint8_t daddr) {
       TU_LOG_P_CDC("close");
 
       // Invoke application callback
-      if (tuh_cdc_umount_cb) tuh_cdc_umount_cb(idx);
+      if (tuh_cdc_umount_cb) {
+        tuh_cdc_umount_cb(idx);
+      }
 
       p_cdc->daddr = 0;
       p_cdc->bInterfaceNumber = 0;
@@ -763,7 +767,7 @@ void cdch_close(uint8_t daddr) {
 
 bool cdch_xfer_cb(uint8_t daddr, uint8_t ep_addr, xfer_result_t event, uint32_t xferred_bytes) {
   // TODO handle stall response, retry failed transfer ...
-  TU_ASSERT(event == XFER_RESULT_SUCCESS);
+  TU_VERIFY(event == XFER_RESULT_SUCCESS);
 
   uint8_t const idx = get_idx_by_ep_addr(daddr, ep_addr);
   cdch_interface_t * p_cdc = get_itf(idx);
@@ -771,20 +775,22 @@ bool cdch_xfer_cb(uint8_t daddr, uint8_t ep_addr, xfer_result_t event, uint32_t
 
   if (ep_addr == p_cdc->stream.tx.ep_addr) {
     // invoke tx complete callback to possibly refill tx fifo
-    if (tuh_cdc_tx_complete_cb) tuh_cdc_tx_complete_cb(idx);
+    if (tuh_cdc_tx_complete_cb) {
+      tuh_cdc_tx_complete_cb(idx);
+    }
 
-    if (0 == tu_edpt_stream_write_xfer(&p_cdc->stream.tx)) {
+    if ( 0 == tu_edpt_stream_write_xfer(daddr, &p_cdc->stream.tx) ) {
       // If there is no data left, a ZLP should be sent if:
       // - xferred_bytes is multiple of EP Packet size and not zero
-      tu_edpt_stream_write_zlp_if_needed(&p_cdc->stream.tx, xferred_bytes);
+      tu_edpt_stream_write_zlp_if_needed(daddr, &p_cdc->stream.tx, xferred_bytes);
     }
   } else if (ep_addr == p_cdc->stream.rx.ep_addr) {
     #if CFG_TUH_CDC_FTDI
-    if (p_cdc->serial_drid == SERIAL_DRIVER_FTDI) {
+    if (p_cdc->serial_drid == SERIAL_DRIVER_FTDI && xferred_bytes > 2) {
       // FTDI reserve 2 bytes for status
       // uint8_t status[2] = {p_cdc->stream.rx.ep_buf[0], p_cdc->stream.rx.ep_buf[1]};
-      tu_edpt_stream_read_xfer_complete_offset(&p_cdc->stream.rx, xferred_bytes, 2);
-    } else
+      tu_edpt_stream_read_xfer_complete_with_buf(&p_cdc->stream.rx, p_cdc->stream.rx.ep_buf+2, xferred_bytes-2);
+    }else
     #endif
     {
       tu_edpt_stream_read_xfer_complete(&p_cdc->stream.rx, xferred_bytes);
@@ -796,8 +802,8 @@ bool cdch_xfer_cb(uint8_t daddr, uint8_t ep_addr, xfer_result_t event, uint32_t
     }
 
     // prepare for next transfer if needed
-    tu_edpt_stream_read_xfer(&p_cdc->stream.rx);
-  } else if (ep_addr == p_cdc->ep_notif) {
+    tu_edpt_stream_read_xfer(daddr, &p_cdc->stream.rx);
+  }else if ( ep_addr == p_cdc->ep_notif ) {
     // TODO handle notification endpoint
   } else {
     TU_ASSERT(false);
@@ -817,9 +823,9 @@ static bool open_ep_stream_pair(cdch_interface_t * p_cdc, tusb_desc_endpoint_t c
     TU_ASSERT(tuh_edpt_open(p_cdc->daddr, desc_ep));
 
     if (tu_edpt_dir(desc_ep->bEndpointAddress) == TUSB_DIR_IN) {
-      tu_edpt_stream_open(&p_cdc->stream.rx, p_cdc->daddr, desc_ep);
+      tu_edpt_stream_open(&p_cdc->stream.rx, desc_ep);
     } else {
-      tu_edpt_stream_open(&p_cdc->stream.tx, p_cdc->daddr, desc_ep);
+      tu_edpt_stream_open(&p_cdc->stream.tx, desc_ep);
     }
 
     desc_ep = (tusb_desc_endpoint_t const *) tu_desc_next(desc_ep);
@@ -836,8 +842,9 @@ bool cdch_open(uint8_t rhport, uint8_t daddr, tusb_desc_interface_t const * itf_
   // Note: Protocol 0xFF can be RNDIS device
   if (TUSB_CLASS_CDC                           == itf_desc->bInterfaceClass &&
       CDC_COMM_SUBCLASS_ABSTRACT_CONTROL_MODEL == itf_desc->bInterfaceSubClass) {
-    driver_detected = &serial_drivers[0];
-  } else if (SERIAL_DRIVER_COUNT > 1 && TUSB_CLASS_VENDOR_SPECIFIC == itf_desc->bInterfaceClass) {
+    return acm_open(daddr, itf_desc, max_len);
+  } else if (SERIAL_DRIVER_COUNT > 1 &&
+             TUSB_CLASS_VENDOR_SPECIFIC == itf_desc->bInterfaceClass) {
     uint16_t vid, pid;
     TU_VERIFY(tuh_vid_pid_get(daddr, &vid, &pid));
 
@@ -876,7 +883,7 @@ static void set_config_complete(uint8_t idx, uint8_t itf_offset, bool success) {
       tuh_cdc_mount_cb(idx);
     }
     // Prepare for incoming data
-    tu_edpt_stream_read_xfer(&p_cdc->stream.rx);
+    tu_edpt_stream_read_xfer(p_cdc->daddr, &p_cdc->stream.rx);
   } else {
     // clear the interface entry
     p_cdc->daddr = 0;
diff --git a/src/class/cdc/cdc_host.h b/src/class/cdc/cdc_host.h
index 27f9170a8..63eb1fc0f 100644
--- a/src/class/cdc/cdc_host.h
+++ b/src/class/cdc/cdc_host.h
@@ -39,22 +39,22 @@
 
 // RX FIFO size
 #ifndef CFG_TUH_CDC_RX_BUFSIZE
-#define CFG_TUH_CDC_RX_BUFSIZE USBH_EPSIZE_BULK_MAX
+#define CFG_TUH_CDC_RX_BUFSIZE TUH_EPSIZE_BULK_MPS
 #endif
 
 // RX Endpoint size
 #ifndef CFG_TUH_CDC_RX_EPSIZE
-#define CFG_TUH_CDC_RX_EPSIZE  USBH_EPSIZE_BULK_MAX
+#define CFG_TUH_CDC_RX_EPSIZE  TUH_EPSIZE_BULK_MPS
 #endif
 
 // TX FIFO size
 #ifndef CFG_TUH_CDC_TX_BUFSIZE
-#define CFG_TUH_CDC_TX_BUFSIZE USBH_EPSIZE_BULK_MAX
+#define CFG_TUH_CDC_TX_BUFSIZE TUH_EPSIZE_BULK_MPS
 #endif
 
 // TX Endpoint size
 #ifndef CFG_TUH_CDC_TX_EPSIZE
-#define CFG_TUH_CDC_TX_EPSIZE  USBH_EPSIZE_BULK_MAX
+#define CFG_TUH_CDC_TX_EPSIZE  TUH_EPSIZE_BULK_MPS
 #endif
 
 //--------------------------------------------------------------------+
@@ -79,8 +79,7 @@ bool tuh_cdc_get_dtr(uint8_t idx);
 bool tuh_cdc_get_rts(uint8_t idx);
 
 // Check if interface is connected (DTR active)
-TU_ATTR_ALWAYS_INLINE static inline bool tuh_cdc_connected(uint8_t idx)
-{
+TU_ATTR_ALWAYS_INLINE static inline bool tuh_cdc_connected(uint8_t idx) {
   return tuh_cdc_get_dtr(idx);
 }