em_usbd.c

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/**************************************************************************/
#include "em_device.h"
#if defined( USB_PRESENT ) && ( USB_COUNT == 1 )
#include "em_usb.h"
#if defined( USB_DEVICE )

#include "em_cmu.h"
#include "em_core.h"
#include "em_system.h"
#include "em_usbtypes.h"
#include "em_usbhal.h"
#include "em_usbd.h"

static USBD_Device_TypeDef device;
USBD_Device_TypeDef *dev = &device;

static const char *stateNames[] =
{
  [ USBD_STATE_NONE       ] = "NONE      ",
  [ USBD_STATE_ATTACHED   ] = "ATTACHED  ",
  [ USBD_STATE_POWERED    ] = "POWERED   ",
  [ USBD_STATE_DEFAULT    ] = "DEFAULT   ",
  [ USBD_STATE_ADDRESSED  ] = "ADDRESSED ",
  [ USBD_STATE_CONFIGURED ] = "CONFIGURED",
  [ USBD_STATE_SUSPENDED  ] = "SUSPENDED ",
  [ USBD_STATE_LASTMARKER ] = "UNDEFINED "
};

/***************************************************************************/
void USBD_AbortAllTransfers( void )
{
  CORE_ATOMIC_SECTION(
    USBDHAL_AbortAllTransfers( USB_STATUS_EP_ABORTED );
  )
}

/***************************************************************************/
int USBD_AbortTransfer( int epAddr )
{
  USB_XferCompleteCb_TypeDef callback;
  USBD_Ep_TypeDef *ep = USBD_GetEpFromAddr( epAddr );
  CORE_DECLARE_IRQ_STATE;

  if ( ep == NULL )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_AbortTransfer(), Illegal endpoint" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  if ( ep->num == 0 )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_AbortTransfer(), Illegal endpoint" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  CORE_ENTER_ATOMIC();
  if ( ep->state == D_EP_IDLE )
  {
    CORE_EXIT_ATOMIC();
    return USB_STATUS_OK;
  }

  USBD_AbortEp( ep );

  ep->state = D_EP_IDLE;
  if ( ep->xferCompleteCb )
  {
    callback = ep->xferCompleteCb;
    ep->xferCompleteCb = NULL;

    if ( ( dev->lastState == USBD_STATE_CONFIGURED ) &&
         ( dev->state     == USBD_STATE_ADDRESSED  )    )
    {
      USBDHAL_DeactivateEp( ep );
    }

    DEBUG_TRACE_ABORT( USB_STATUS_EP_ABORTED );
    callback( USB_STATUS_EP_ABORTED, ep->xferred, ep->remaining );
  }

  CORE_EXIT_ATOMIC();
  return USB_STATUS_OK;
}

/***************************************************************************/
void USBD_Connect( void )
{
  CORE_ATOMIC_SECTION(
    USBDHAL_Connect();
  )
}

/***************************************************************************/
void USBD_Disconnect( void )
{
  CORE_ATOMIC_SECTION(
    USBDHAL_Disconnect();
  )
}

/***************************************************************************/
bool USBD_EpIsBusy( int epAddr )
{
  USBD_Ep_TypeDef *ep = USBD_GetEpFromAddr( epAddr );

  if ( ep == NULL )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_EpIsBusy(), Illegal endpoint" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  if ( ep->state == D_EP_IDLE )
    return false;

  return true;
}

/***************************************************************************/
USBD_State_TypeDef USBD_GetUsbState( void )
{
  return dev->state;
}

/***************************************************************************/
const char *USBD_GetUsbStateName( USBD_State_TypeDef state )
{
  if ( state > USBD_STATE_LASTMARKER )
    state = USBD_STATE_LASTMARKER;

  return stateNames[ state ];
}

/***************************************************************************/
int USBD_Init( const USBD_Init_TypeDef *p )
{
  int numEps;
  USBD_Ep_TypeDef *ep;
  uint8_t txFifoNum;
  uint8_t *conf, *confEnd;
#if defined( CMU_OSCENCMD_USHFRCOEN )
  SYSTEM_ChipRevision_TypeDef chipRev;
#endif
  USB_EndpointDescriptor_TypeDef *epd;
  USB_InterfaceDescriptor_TypeDef *id;
  uint32_t totalRxFifoSize, totalTxFifoSize, numInEps, numOutEps;
  CORE_DECLARE_IRQ_STATE;

#if !defined( USB_CORECLK_HFRCO ) || !defined( CMU_OSCENCMD_USHFRCOEN )
  /* Devices supporting crystal-less USB can use HFRCO or HFXO as core clock. */
  /* All other devices must use HFXO as core clock.                           */
  if ( CMU_ClockSelectGet( cmuClock_HF ) != cmuSelect_HFXO )
  {
    CMU_ClockSelectSet( cmuClock_HF, cmuSelect_HFXO );
  }
#endif

#if !defined( CMU_OSCENCMD_USHFRCOEN )
#if ( USB_USBC_32kHz_CLK == USB_USBC_32kHz_CLK_LFXO )
  CMU_OscillatorEnable(cmuOsc_LFXO, true, false);
#else
  CMU_OscillatorEnable(cmuOsc_LFRCO, true, false);
#endif

#else
  CMU_ClockEnable(cmuClock_CORELE, true);
  /* LFC clock is needed to detect USB suspend when LEMIDLE is activated. */
#if ( USB_USBC_32kHz_CLK == USB_USBC_32kHz_CLK_LFXO )
  CMU_ClockSelectSet(cmuClock_LFC, cmuSelect_LFXO);
#else
  CMU_ClockSelectSet(cmuClock_LFC, cmuSelect_LFRCO);
#endif
  CMU_ClockEnable(cmuClock_USBLE, true);
#endif

  USBTIMER_Init();

  memset( dev, 0, sizeof( USBD_Device_TypeDef ) );

  dev->setup                = dev->setupPkt;
  dev->deviceDescriptor     = p->deviceDescriptor;
  dev->configDescriptor     = (USB_ConfigurationDescriptor_TypeDef*)
                              p->configDescriptor;
  dev->stringDescriptors    = p->stringDescriptors;
  dev->numberOfStrings      = p->numberOfStrings;
  dev->state                = USBD_STATE_LASTMARKER;
  dev->savedState           = USBD_STATE_NONE;
  dev->lastState            = USBD_STATE_NONE;
  dev->callbacks            = p->callbacks;
  dev->remoteWakeupEnabled  = false;

  /* Initialize EP0 */

  ep                 = &dev->ep[ 0 ];
  ep->in             = false;
  ep->buf            = NULL;
  ep->num            = 0;
  ep->mask           = 1;
  ep->addr           = 0;
  ep->type           = USB_EPTYPE_CTRL;
  ep->txFifoNum      = 0;
  ep->packetSize     = p->deviceDescriptor->bMaxPacketSize0;

  if ( ep->packetSize == 32 )
  {
    dev->ep0MpsCode = _USB_DOEP0CTL_MPS_32B;
  }
  else if ( ep->packetSize == 64 )
  {
    dev->ep0MpsCode = _USB_DOEP0CTL_MPS_64B;
  }
  else
  {
    return USB_STATUS_ILLEGAL;
  }

  ep->remaining      = 0;
  ep->xferred        = 0;
  ep->state          = D_EP_IDLE;
  ep->xferCompleteCb = NULL;
  ep->fifoSize       = ep->packetSize / 4;

  totalTxFifoSize = ep->fifoSize * p->bufferingMultiplier[ 0 ];
  totalRxFifoSize = (ep->fifoSize + 1) * p->bufferingMultiplier[ 0 ];

#if defined( DEBUG_USB_API )
  /* Do a sanity check on the configuration descriptor */
  {
    int i;

    /* Check if bLength's adds up exactly to wTotalLength */
    i = 0;
    conf = (uint8_t*)dev->configDescriptor;
    confEnd = conf + dev->configDescriptor->wTotalLength;

    while ( conf < confEnd )
    {
      if ( *conf == 0 )
        break;

      i += *conf;
      conf += *conf;
    }

    if ( ( conf != confEnd                          ) ||
         ( i != dev->configDescriptor->wTotalLength )    )
    {
      DEBUG_USB_API_PUTS( "\nUSBD_Init(), Illegal configuration descriptor" );
      EFM_ASSERT( false );
      return USB_STATUS_ILLEGAL;
    }
  }
#endif /* defined( DEBUG_USB_API ) */

  /* Parse configuration decriptor */
  numEps = 0;
  numInEps  = 0;
  numOutEps = 0;
  conf = (uint8_t*)dev->configDescriptor;
  confEnd = conf + dev->configDescriptor->wTotalLength;

  txFifoNum = 1;
  while ( conf < confEnd )
  {
    if ( *conf == 0 )
    {
      DEBUG_USB_API_PUTS( "\nUSBD_Init(), Illegal configuration descriptor" );
      EFM_ASSERT( false );
      return USB_STATUS_ILLEGAL;
    }

    if ( *(conf + 1) == USB_ENDPOINT_DESCRIPTOR )
    {
      numEps++;
      epd = (USB_EndpointDescriptor_TypeDef*)conf;

#if defined( __GNUC__ )
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Warray-bounds"
#endif
      ep                 = &dev->ep[ numEps ];
#if defined( __GNUC__ )
#pragma GCC diagnostic pop
#endif

      ep->in             = ( epd->bEndpointAddress & USB_SETUP_DIR_MASK ) != 0;
      ep->buf            = NULL;
      ep->addr           = epd->bEndpointAddress;
      ep->num            = ep->addr & USB_EPNUM_MASK;
      ep->mask           = 1 << ep->num;
      ep->type           = epd->bmAttributes & CONFIG_DESC_BM_TRANSFERTYPE;
      ep->packetSize     = epd->wMaxPacketSize;
      ep->remaining      = 0;
      ep->xferred        = 0;
      ep->state          = D_EP_IDLE;
      ep->xferCompleteCb = NULL;

      if ( p->bufferingMultiplier[ numEps ] == 0 )
      {
        DEBUG_USB_API_PUTS( "\nUSBD_Init(), Illegal EP fifo buffer configuration" );
        EFM_ASSERT( false );
        return USB_STATUS_ILLEGAL;
      }

      if ( ep->in )
      {
        numInEps++;
        ep->txFifoNum = txFifoNum++;
        ep->fifoSize = ( ( ep->packetSize + 3 ) / 4 )
                       * p->bufferingMultiplier[ numEps ];
        dev->inEpAddr2EpIndex[ ep->num ] = numEps;
        totalTxFifoSize += ep->fifoSize;
        if ( ep->num > MAX_NUM_IN_EPS )
        {
          DEBUG_USB_API_PUTS( "\nUSBD_Init(), Illegal IN EP address" );
          EFM_ASSERT( false );
          return USB_STATUS_ILLEGAL;
        }
      }
      else
      {
        numOutEps++;
        ep->fifoSize = ( ( ( ep->packetSize + 3 ) / 4 ) + 1 )
                       * p->bufferingMultiplier[ numEps ];
        dev->outEpAddr2EpIndex[ ep->num ] = numEps;
        totalRxFifoSize += ep->fifoSize;
        if ( ep->num > MAX_NUM_OUT_EPS )
        {
          DEBUG_USB_API_PUTS( "\nUSBD_Init(), Illegal OUT EP address" );
          EFM_ASSERT( false );
          return USB_STATUS_ILLEGAL;
        }
      }
    }
    else if ( *(conf + 1) == USB_INTERFACE_DESCRIPTOR )
    {
      id = (USB_InterfaceDescriptor_TypeDef*)conf;

      if ( id->bAlternateSetting == 0 )     // Only check default interfaces
      {
        if ( dev->numberOfInterfaces != id->bInterfaceNumber )
        {
          DEBUG_USB_API_PUTS( "\nUSBD_Init(), Illegal interface number" );
          EFM_ASSERT( false );
          return USB_STATUS_ILLEGAL;
        }
      dev->numberOfInterfaces++;
      }
    }

    conf += *conf;
  }

  /* Rx-FIFO size: SETUP packets : 4*n + 6    n=#CTRL EP's
   *               GOTNAK        : 1
   *               Status info   : 2*n        n=#OUT EP's (EP0 included) in HW
   */
  totalRxFifoSize += 10 + 1 + ( 2 * (MAX_NUM_OUT_EPS + 1) );

  if ( dev->configDescriptor->bNumInterfaces != dev->numberOfInterfaces )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_Init(), Illegal interface count" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  if ( numEps != NUM_EP_USED )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_Init(), Illegal EP count" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  if ( numInEps > MAX_NUM_IN_EPS )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_Init(), Illegal IN EP count" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  if ( numOutEps > MAX_NUM_OUT_EPS )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_Init(), Illegal OUT EP count" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  CORE_ENTER_ATOMIC();

  /* Enable USB clock */
  CMU->HFCORECLKEN0 |= CMU_HFCORECLKEN0_USB | CMU_HFCORECLKEN0_USBC;

#if defined( CMU_OSCENCMD_USHFRCOEN )
  CMU->USHFRCOCONF = CMU_USHFRCOCONF_BAND_48MHZ;
  CMU_ClockSelectSet( cmuClock_USBC, cmuSelect_USHFRCO );

  /* Enable USHFRCO Clock Recovery mode. */
  CMU->USBCRCTRL |= CMU_USBCRCTRL_EN;

  /* Turn on Low Energy Mode (LEM) features. */
  SYSTEM_ChipRevisionGet(&chipRev);
  if ((chipRev.family == 5)
      && (chipRev.major == 1)
      && (chipRev.minor == 0))
  {
    /* First Happy Gecko chip revision did not have all LEM features enabled. */
    USB->CTRL = USB_CTRL_LEMOSCCTRL_GATE
                | USB_CTRL_LEMIDLEEN
                | USB_CTRL_LEMPHYCTRL;
  }
  else
  {
    USB->CTRL = USB_CTRL_LEMOSCCTRL_GATE
                | USB_CTRL_LEMIDLEEN
                | USB_CTRL_LEMPHYCTRL
                | USB_CTRL_LEMNAKEN
                | USB_CTRL_LEMADDRMEN;
  }
#else
  CMU_ClockSelectSet( cmuClock_USBC, cmuSelect_HFCLK );
#endif

  USBHAL_DisableGlobalInt();

  if ( USBDHAL_CoreInit( totalRxFifoSize, totalTxFifoSize ) == USB_STATUS_OK )
  {
    USBDHAL_EnableUsbResetAndSuspendInt();
    USBHAL_EnableGlobalInt();
    NVIC_ClearPendingIRQ( USB_IRQn );
    NVIC_EnableIRQ( USB_IRQn );
  }
  else
  {
    CORE_EXIT_ATOMIC();
    DEBUG_USB_API_PUTS( "\nUSBD_Init(), FIFO setup error" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

#if ( USB_PWRSAVE_MODE & USB_PWRSAVE_MODE_ONVBUSOFF )
  if ( USBHAL_VbusIsOn() )
  {
    USBD_SetUsbState( USBD_STATE_POWERED );
  }
  else
#endif
  {
    USBD_SetUsbState( USBD_STATE_NONE );
  }

  CORE_EXIT_ATOMIC();
  return USB_STATUS_OK;
}

/***************************************************************************/
int USBD_Read( int epAddr, void *data, int byteCount,
               USB_XferCompleteCb_TypeDef callback )
{
  CORE_DECLARE_IRQ_STATE;
  USBD_Ep_TypeDef *ep = USBD_GetEpFromAddr( epAddr );

  if ( ep == NULL )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_Read(), Illegal endpoint" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  if ( (   byteCount > MAX_XFER_LEN                           ) ||
       ( ( byteCount / ep->packetSize ) > MAX_PACKETS_PR_XFER )    )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_Read(), Illegal transfer size" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  if ( (uint32_t)data & 3 )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_Read(), Misaligned data buffer" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  CORE_ENTER_ATOMIC();
  if ( USBDHAL_EpIsStalled( ep ) )
  {
    CORE_EXIT_ATOMIC();
    DEBUG_USB_API_PUTS( "\nUSBD_Read(), Endpoint is halted" );
    return USB_STATUS_EP_STALLED;
  }

  if ( ep->state != D_EP_IDLE )
  {
    CORE_EXIT_ATOMIC();
    DEBUG_USB_API_PUTS( "\nUSBD_Read(), Endpoint is busy" );
    return USB_STATUS_EP_BUSY;
  }

  if ( ( ep->num > 0 ) && ( USBD_GetUsbState() != USBD_STATE_CONFIGURED ) )
  {
    CORE_EXIT_ATOMIC();
    DEBUG_USB_API_PUTS( "\nUSBD_Read(), Device not configured" );
    return USB_STATUS_DEVICE_UNCONFIGURED;
  }

  ep->buf       = (uint8_t*)data;
  ep->remaining = byteCount;
  ep->xferred   = 0;

  if ( ep->num == 0 )
  {
    ep->in = false;
  }
  else if ( ep->in != false )
  {
    CORE_EXIT_ATOMIC();
    DEBUG_USB_API_PUTS( "\nUSBD_Read(), Illegal EP direction" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  ep->state          = D_EP_RECEIVING;
  ep->xferCompleteCb = callback;

  USBD_ArmEp( ep );
  CORE_EXIT_ATOMIC();
  return USB_STATUS_OK;
}

/***************************************************************************/
int USBD_RemoteWakeup( void )
{
  CORE_DECLARE_IRQ_STATE;

  CORE_ENTER_ATOMIC();

  if ( ( dev->state != USBD_STATE_SUSPENDED ) ||
       ( dev->remoteWakeupEnabled == false  )    )
  {
    CORE_EXIT_ATOMIC();
    DEBUG_USB_API_PUTS( "\nUSBD_RemoteWakeup(), Illegal remote wakeup" );
    return USB_STATUS_ILLEGAL;
  }

  USBDINT_RemoteWakeup();
  CORE_EXIT_ATOMIC();
  return USB_STATUS_OK;
}

/***************************************************************************/
bool USBD_SafeToEnterEM2( void )
{
#if ( USB_PWRSAVE_MODE )
  return USBD_poweredDown ? true : false;
#else
  return false;
#endif
}

void USBD_SetUsbState( USBD_State_TypeDef newState )
{
  USBD_State_TypeDef currentState;

  currentState = dev->state;
  if ( newState == USBD_STATE_SUSPENDED )
  {
    dev->savedState = currentState;
  }

  dev->lastState = dev->state;
  dev->state = newState;

  if ( ( dev->callbacks->usbStateChange ) &&
       ( currentState != newState       )    )
  {
    dev->callbacks->usbStateChange( currentState, newState );
  }
}

/***************************************************************************/
int USBD_StallEp( int epAddr )
{
  USB_Status_TypeDef retVal;
  USBD_Ep_TypeDef *ep = USBD_GetEpFromAddr( epAddr );

  if ( ep == NULL )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_StallEp(), Illegal request" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  if ( ep->num == 0 )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_StallEp(), Illegal endpoint" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  CORE_ATOMIC_SECTION(
    retVal = USBDHAL_StallEp( ep );
  )

  if ( retVal != USB_STATUS_OK )
  {
    retVal = USB_STATUS_ILLEGAL;
  }

  return retVal;
}

/***************************************************************************/
void USBD_Stop( void )
{
  USBD_Disconnect();
  NVIC_DisableIRQ( USB_IRQn );
  USBHAL_DisableGlobalInt();
  USBHAL_DisableUsbInt();
  USBHAL_DisablePhyPins();
  USBD_SetUsbState( USBD_STATE_NONE );
  /* Turn off USB clocks. */
  CMU->HFCORECLKEN0 &= ~(CMU_HFCORECLKEN0_USB | CMU_HFCORECLKEN0_USBC);
}

/***************************************************************************/
int USBD_UnStallEp( int epAddr )
{
  USB_Status_TypeDef retVal;
  USBD_Ep_TypeDef *ep = USBD_GetEpFromAddr( epAddr );

  if ( ep == NULL )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_UnStallEp(), Illegal request" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  if ( ep->num == 0 )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_UnStallEp(), Illegal endpoint" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  CORE_ATOMIC_SECTION(
    retVal = USBDHAL_UnStallEp( ep );
  )

  if ( retVal != USB_STATUS_OK )
  {
    retVal = USB_STATUS_ILLEGAL;
  }

  return retVal;
}

/***************************************************************************/
int USBD_Write( int epAddr, void *data, int byteCount,
                USB_XferCompleteCb_TypeDef callback )
{
  CORE_DECLARE_IRQ_STATE;
  USBD_Ep_TypeDef *ep = USBD_GetEpFromAddr( epAddr );

  if ( ep == NULL )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_Write(), Illegal endpoint" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  if ( (   byteCount > MAX_XFER_LEN                           ) ||
       ( ( byteCount / ep->packetSize ) > MAX_PACKETS_PR_XFER )    )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_Write(), Illegal transfer size" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  if ( (uint32_t)data & 3 )
  {
    DEBUG_USB_API_PUTS( "\nUSBD_Write(), Misaligned data buffer" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  CORE_ENTER_ATOMIC();
  if ( USBDHAL_EpIsStalled( ep ) )
  {
    CORE_EXIT_ATOMIC();
    DEBUG_USB_API_PUTS( "\nUSBD_Write(), Endpoint is halted" );
    return USB_STATUS_EP_STALLED;
  }

  if ( ep->state != D_EP_IDLE )
  {
    CORE_EXIT_ATOMIC();
    DEBUG_USB_API_PUTS( "\nUSBD_Write(), Endpoint is busy" );
    return USB_STATUS_EP_BUSY;
  }

  if ( ( ep->num > 0 ) && ( USBD_GetUsbState() != USBD_STATE_CONFIGURED ) )
  {
    CORE_EXIT_ATOMIC();
    DEBUG_USB_API_PUTS( "\nUSBD_Write(), Device not configured" );
    return USB_STATUS_DEVICE_UNCONFIGURED;
  }

  ep->buf       = (uint8_t*)data;
  ep->remaining = byteCount;
  ep->xferred   = 0;

  if ( ep->num == 0 )
  {
    ep->in = true;
  }
  else if ( ep->in != true )
  {
    CORE_EXIT_ATOMIC();
    DEBUG_USB_API_PUTS( "\nUSBD_Write(), Illegal EP direction" );
    EFM_ASSERT( false );
    return USB_STATUS_ILLEGAL;
  }

  ep->state          = D_EP_TRANSMITTING;
  ep->xferCompleteCb = callback;

  USBD_ArmEp( ep );
  CORE_EXIT_ATOMIC();
  return USB_STATUS_OK;
}

#if defined(USB_HOST)
/***************************************************************************/
/***************************************************************************/
/***************************************************************************/
#else
/***************************************************************************/
/***************************************************************************/
#endif
/***************************************************************************/
/******** THE REST OF THE FILE IS DOCUMENTATION ONLY !**********************/
#endif /* defined( USB_DEVICE ) */
#endif /* defined( USB_PRESENT ) && ( USB_COUNT == 1 ) */