/**************************************************************************/
/*!
    @file     dcd_lpc175x_6x.c
    @author   hathach (tinyusb.org)

    @section LICENSE

    Software License Agreement (BSD License)

    Copyright (c) 2013, hathach (tinyusb.org)
    All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are met:
    1. Redistributions of source code must retain the above copyright
    notice, this list of conditions and the following disclaimer.
    2. Redistributions in binary form must reproduce the above copyright
    notice, this list of conditions and the following disclaimer in the
    documentation and/or other materials provided with the distribution.
    3. Neither the name of the copyright holders nor the
    names of its contributors may be used to endorse or promote products
    derived from this software without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS'' AND ANY
    EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
    WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
    DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE FOR ANY
    DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
    (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
    LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
    ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    This file is part of the tinyusb stack.
*/
/**************************************************************************/

#include "tusb_option.h"

#if TUSB_OPT_DEVICE_ENABLED && (CFG_TUSB_MCU == OPT_MCU_LPC175X_6X)

#include "device/dcd.h"
#include "dcd_lpc175x_6x.h"
#include "LPC17xx.h"

//--------------------------------------------------------------------+
// MACRO CONSTANT TYPEDEF
//--------------------------------------------------------------------+
#define DCD_ENDPOINT_MAX 32

typedef struct ATTR_ALIGNED(4)
{
  //------------- Word 0 -------------//
  uint32_t next;

  //------------- Word 1 -------------//
  uint16_t mode            : 2; // either 00 normal or 01 ATLE(auto length extraction)
  uint16_t next_valid      : 1;
  uint16_t                 : 1; ///< reserved
  uint16_t isochronous     : 1; // is an iso endpoint
  uint16_t max_packet_size : 11;
  volatile uint16_t buflen; // bytes for non-iso, number of packets for iso endpoint

  //------------- Word 2 -------------//
  volatile uint32_t buffer;

  //------------- Word 3 -------------//
  volatile uint16_t retired                : 1; // initialized to zero
  volatile uint16_t status                 : 4;
  volatile uint16_t iso_last_packet_valid  : 1;
  volatile uint16_t atle_lsb_extracted     : 1;	// used in ATLE mode
  volatile uint16_t atle_msb_extracted     : 1;	// used in ATLE mode
  volatile uint16_t atle_mess_len_position : 6; // used in ATLE mode
  uint16_t                                 : 2;
  volatile uint16_t present_count;  // For non-iso : The number of bytes transferred by the DMA engine
                                    // For iso : number of packets

  //------------- Word 4 -------------//
  //	uint32_t iso_packet_size_addr;		// iso only, can be omitted for non-iso
}dma_desc_t;

TU_VERIFY_STATIC( sizeof(dma_desc_t) == 16, "size is not correct"); // TODO not support ISO for now

typedef struct
{
  // must be 128 byte aligned
  volatile dma_desc_t* udca[DCD_ENDPOINT_MAX];

  // TODO DMA does not support control transfer (0-1 are not used, offset to reduce memory)
  dma_desc_t dd[DCD_ENDPOINT_MAX];

  struct
  {
    uint8_t* out_buffer;
    uint8_t  out_bytes;
    volatile bool out_received; // indicate if data is already received in endpoint

    uint8_t  in_bytes;
  } control;

} dcd_data_t;

ATTR_ALIGNED(128) static dcd_data_t _dcd;


//--------------------------------------------------------------------+
// SIE Command
//--------------------------------------------------------------------+
static void sie_cmd_code (sie_cmdphase_t phase, uint8_t code_data)
{
  LPC_USB->USBDevIntClr = (DEV_INT_COMMAND_CODE_EMPTY_MASK | DEV_INT_COMMAND_DATA_FULL_MASK);
  LPC_USB->USBCmdCode   = (phase << 8) | (code_data << 16);

  uint32_t const wait_flag = (phase == SIE_CMDPHASE_READ) ? DEV_INT_COMMAND_DATA_FULL_MASK : DEV_INT_COMMAND_CODE_EMPTY_MASK;
  while ((LPC_USB->USBDevIntSt & wait_flag) == 0) {}

  LPC_USB->USBDevIntClr = wait_flag;
}

static void sie_write (uint8_t cmd_code, uint8_t data_len, uint8_t data)
{
  sie_cmd_code(SIE_CMDPHASE_COMMAND, cmd_code);

  if (data_len)
  {
    sie_cmd_code(SIE_CMDPHASE_WRITE, data);
  }
}

static uint32_t sie_read (uint8_t cmd_code, uint8_t data_len)
{
  // TODO multiple read
  sie_cmd_code(SIE_CMDPHASE_COMMAND , cmd_code);
  sie_cmd_code(SIE_CMDPHASE_READ    , cmd_code);
  return LPC_USB->USBCmdData;
}

//--------------------------------------------------------------------+
// PIPE HELPER
//--------------------------------------------------------------------+
static inline uint8_t ep_addr2idx(uint8_t ep_addr)
{
  return 2*(ep_addr & 0x0F) + ((ep_addr & TUSB_DIR_IN_MASK) ? 1 : 0);
}

static void set_ep_size(uint8_t ep_id, uint16_t max_packet_size)
{
  // follows example in 11.10.4.2
  LPC_USB->USBReEp    |= BIT_(ep_id);
  LPC_USB->USBEpInd    = ep_id; // select index before setting packet size
  LPC_USB->USBMaxPSize = max_packet_size;

  while ((LPC_USB->USBDevIntSt & DEV_INT_ENDPOINT_REALIZED_MASK) == 0) {} // TODO can be omitted
  LPC_USB->USBDevIntClr = DEV_INT_ENDPOINT_REALIZED_MASK;
}


//--------------------------------------------------------------------+
// CONTROLLER API
//--------------------------------------------------------------------+
static void bus_reset(void)
{
  // step 7 : slave mode set up
  LPC_USB->USBEpIntClr     = 0xFFFFFFFF;          // clear all pending interrupt
  LPC_USB->USBDevIntClr    = 0xFFFFFFFF;          // clear all pending interrupt
  LPC_USB->USBEpIntEn      = (uint32_t) BIN8(11); // control endpoint cannot use DMA, non-control all use DMA
  LPC_USB->USBEpIntPri     = 0;                   // same priority for all endpoint

  // step 8 : DMA set up
  LPC_USB->USBEpDMADis     = 0xFFFFFFFF; // firstly disable all dma
  LPC_USB->USBDMARClr      = 0xFFFFFFFF; // clear all pending interrupt
  LPC_USB->USBEoTIntClr    = 0xFFFFFFFF;
  LPC_USB->USBNDDRIntClr   = 0xFFFFFFFF;
  LPC_USB->USBSysErrIntClr = 0xFFFFFFFF;

  tu_memclr(&_dcd, sizeof(dcd_data_t));
}

bool dcd_init(uint8_t rhport)
{
  (void) rhport;

  //------------- user manual 11.13 usb device controller initialization -------------//  LPC_USB->USBEpInd = 0;
  // step 6 : set up control endpoint
  set_ep_size(0, CFG_TUD_ENDOINT0_SIZE);
  set_ep_size(1, CFG_TUD_ENDOINT0_SIZE);

  bus_reset();

  LPC_USB->USBDevIntEn = (DEV_INT_DEVICE_STATUS_MASK | DEV_INT_ENDPOINT_SLOW_MASK | DEV_INT_ERROR_MASK);
  LPC_USB->USBUDCAH = (uint32_t) _dcd.udca;
  LPC_USB->USBDMAIntEn = (DMA_INT_END_OF_XFER_MASK | DMA_INT_ERROR_MASK);

  sie_write(SIE_CMDCODE_DEVICE_STATUS, 1, 1);    // connect

  NVIC_EnableIRQ(USB_IRQn);

  return TUSB_ERROR_NONE;
}

void dcd_connect(uint8_t rhport)
{
  (void) rhport;
  sie_write(SIE_CMDCODE_DEVICE_STATUS, 1, 1);
}

void dcd_set_address(uint8_t rhport, uint8_t dev_addr)
{
  (void) rhport;
  sie_write(SIE_CMDCODE_SET_ADDRESS, 1, 0x80 | dev_addr); // 7th bit is : device_enable
}

void dcd_set_config(uint8_t rhport, uint8_t config_num)
{
  (void) rhport;
  (void) config_num;
  sie_write(SIE_CMDCODE_CONFIGURE_DEVICE, 1, 1);
}

//--------------------------------------------------------------------+
// CONTROL HELPER
//--------------------------------------------------------------------+
static inline uint8_t byte2dword(uint8_t bytes)
{
  return (bytes + 3) / 4; // length in dwords
}

static void control_ep_write(void const * buffer, uint8_t len)
{
  uint32_t const * buf32 = (uint32_t const *) buffer;

  LPC_USB->USBCtrl   = USBCTRL_WRITE_ENABLE_MASK; // logical endpoint = 0
  LPC_USB->USBTxPLen = (uint32_t) len;

  for (uint8_t count = 0; count < byte2dword(len); count++)
  {
    LPC_USB->USBTxData = *buf32; // NOTE: cortex M3 have no problem with alignment
    buf32++;
  }

  LPC_USB->USBCtrl = 0;

  // select control IN & validate the endpoint
  sie_write(SIE_CMDCODE_ENDPOINT_SELECT+1, 0, 0);
  sie_write(SIE_CMDCODE_BUFFER_VALIDATE  , 0, 0);
}

static uint8_t control_ep_read(void * buffer, uint8_t len)
{
  LPC_USB->USBCtrl = USBCTRL_READ_ENABLE_MASK; // logical endpoint = 0
  while ((LPC_USB->USBRxPLen & USBRXPLEN_PACKET_READY_MASK) == 0) {} // TODO blocking, should have timeout

  len = tu_min8(len, (uint8_t) (LPC_USB->USBRxPLen & USBRXPLEN_PACKET_LENGTH_MASK) );
  uint32_t *buf32 = (uint32_t*) buffer;

  for (uint8_t count=0; count < byte2dword(len); count++)
  {
    *buf32 = LPC_USB->USBRxData;
    buf32++;
  }

  LPC_USB->USBCtrl = 0;

  // select control OUT & clear the endpoint
  sie_write(SIE_CMDCODE_ENDPOINT_SELECT+0, 0, 0);
  sie_write(SIE_CMDCODE_BUFFER_CLEAR     , 0, 0);

  return len;
}

//--------------------------------------------------------------------+
// DCD Endpoint Port
//--------------------------------------------------------------------+
bool dcd_edpt_open(uint8_t rhport, tusb_desc_endpoint_t const * p_endpoint_desc)
{
  (void) rhport;

  uint8_t const epnum = edpt_number(p_endpoint_desc->bEndpointAddress);
  uint8_t const ep_id = ep_addr2idx(p_endpoint_desc->bEndpointAddress);

  // Endpoint type is fixed to endpoint number
  // 1: interrupt, 2: Bulk, 3: Iso and so on
  switch ( p_endpoint_desc->bmAttributes.xfer )
  {
    case TUSB_XFER_INTERRUPT:
      TU_ASSERT((epnum % 3) == 1);
      break;

    case TUSB_XFER_BULK:
      TU_ASSERT((epnum % 3) == 2 || (epnum == 15));
      break;

    case TUSB_XFER_ISOCHRONOUS:
      TU_ASSERT((epnum % 3) == 3 && (epnum != 15));
      break;

    default:
      break;
  }

  //------------- Realize Endpoint with Max Packet Size -------------//
  set_ep_size(ep_id, p_endpoint_desc->wMaxPacketSize.size);

  //------------- first DD prepare -------------//
  dma_desc_t* const dd = &_dcd.dd[ep_id];
  tu_memclr(dd, sizeof(dma_desc_t));

  dd->isochronous = (p_endpoint_desc->bmAttributes.xfer == TUSB_XFER_ISOCHRONOUS) ? 1 : 0;
  dd->max_packet_size = p_endpoint_desc->wMaxPacketSize.size;

  sie_write(SIE_CMDCODE_ENDPOINT_SET_STATUS + ep_id, 1, 0);    // clear all endpoint status

  return true;
}

bool dcd_edpt_busy(uint8_t rhport, uint8_t ep_addr)
{
  (void) rhport;

  uint8_t ep_id = ep_addr2idx( ep_addr );
  return (_dcd.udca[ep_id] != NULL && !_dcd.udca[ep_id]->retired);
}

void dcd_edpt_stall(uint8_t rhport, uint8_t ep_addr)
{
  (void) rhport;

  if ( edpt_number(ep_addr) == 0 )
  {
    sie_write(SIE_CMDCODE_ENDPOINT_SET_STATUS+0, 1, SIE_SET_ENDPOINT_STALLED_MASK | SIE_SET_ENDPOINT_CONDITION_STALLED_MASK);
  }else
  {
    uint8_t ep_id = ep_addr2idx( ep_addr );
    sie_write(SIE_CMDCODE_ENDPOINT_SET_STATUS+ep_id, 1, SIE_SET_ENDPOINT_STALLED_MASK);
  }
}

void dcd_edpt_clear_stall(uint8_t rhport, uint8_t ep_addr)
{
  (void) rhport;
  uint8_t ep_id = ep_addr2idx(ep_addr);

  sie_write(SIE_CMDCODE_ENDPOINT_SET_STATUS+ep_id, 1, 0);
}

bool dcd_edpt_stalled (uint8_t rhport, uint8_t ep_addr)
{
  (void) rhport;
  // TODO implement later
  return false;
}

static bool control_xact(uint8_t rhport, uint8_t dir, uint8_t * buffer, uint8_t len)
{
  (void) rhport;

  if ( dir )
  {
    _dcd.control.in_bytes = len;
    control_ep_write(buffer, len);
  }else
  {
    if ( _dcd.control.out_received )
    {
      // Already received the DATA OUT packet
      _dcd.control.out_received = false;
      _dcd.control.out_buffer = NULL;
      _dcd.control.out_bytes  = 0;

      uint8_t received = control_ep_read(buffer, len);
      dcd_event_xfer_complete(0, 0, received, XFER_RESULT_SUCCESS, true);
    }else
    {
      _dcd.control.out_buffer = buffer;
      _dcd.control.out_bytes  = len;
    }
  }

  return true;
}

bool dcd_edpt_xfer (uint8_t rhport, uint8_t ep_addr, uint8_t* buffer, uint16_t total_bytes)
{
  // Control transfer is not DMA support, and must be done in slave mode
  if ( edpt_number(ep_addr) == 0 )
  {
    return control_xact(rhport, edpt_dir(ep_addr), buffer, (uint8_t) total_bytes);
  }
  else
  {
    uint8_t ep_id = ep_addr2idx(ep_addr);
    dma_desc_t* dd = &_dcd.dd[ep_id];

    // Isochronous & max packet size must be preserved
    // Other fields of dd should be clear
    uint16_t const ep_size = dd->max_packet_size;
    uint8_t  is_iso = dd->isochronous;

    tu_memclr(dd, sizeof(dma_desc_t));
    dd->isochronous = is_iso;
    dd->max_packet_size = ep_size;
    dd->buffer = buffer;
    dd->buflen = total_bytes;

    _dcd.udca[ep_id] = dd;

    // Enable DMA
    LPC_USB->USBEpDMAEn = BIT_(ep_id);

    if ( ep_id % 2 )
    {
      // endpoint IN need to actively raise DMA request
      LPC_USB->USBDMARSet = BIT_(ep_id);
    }

    return true;
  }
}

//--------------------------------------------------------------------+
// ISR
//--------------------------------------------------------------------+
static void normal_xfer_isr (uint8_t rhport, uint32_t eot_int)
{
  for ( uint8_t ep_id = 2; ep_id < DCD_ENDPOINT_MAX; ep_id++ )
  {
    if ( BIT_TEST_(eot_int, ep_id) )
    {
      dma_desc_t* const dd = &_dcd.dd[ep_id];
      uint8_t result = (dd->status == DD_STATUS_NORMAL || dd->status == DD_STATUS_DATA_UNDERUN) ? XFER_RESULT_SUCCESS : XFER_RESULT_FAILED;
      uint8_t const ep_addr = (ep_id / 2) | ((ep_id & 0x01) ? TUSB_DIR_IN_MASK : 0);

      dcd_event_xfer_complete(rhport, ep_addr, dd->present_count, result, true);
    }
  }
}

static void control_xfer_isr(uint8_t rhport)
{
  uint32_t const ep_int_status = LPC_USB->USBEpIntSt & LPC_USB->USBEpIntEn;
//  LPC_USB->USBEpIntClr = ep_int_status; // acknowledge interrupt TODO cannot immediately acknowledge setup packet

  // Control out complete
  if ( ep_int_status & BIT_(0) )
  {
    if (sie_read(SIE_CMDCODE_ENDPOINT_SELECT+0, 1) & SIE_SELECT_ENDPOINT_SETUP_RECEIVED_MASK)
    {
      // Setup received
      (void) sie_read(SIE_CMDCODE_ENDPOINT_SELECT_CLEAR_INTERRUPT+0, 1); // clear setup bit

      uint8_t setup_packet[8];
      control_ep_read(setup_packet, 8); // TODO read before clear setup above

      dcd_event_setup_received(rhport, setup_packet, true);
    }
    else if ( _dcd.control.out_buffer )
    {
      // software queued transfer previously
      uint8_t received = control_ep_read(_dcd.control.out_buffer, _dcd.control.out_bytes);

      _dcd.control.out_buffer = NULL;
      _dcd.control.out_bytes = 0;

      dcd_event_xfer_complete(rhport, 0, received, XFER_RESULT_SUCCESS, true);
    }else
    {
      // hardware auto ack packet -> mark as received
      _dcd.control.out_received = true;
    }
  }

    // Control In complete
  if ( ep_int_status & BIT_(1) )
  {
    dcd_event_xfer_complete(rhport, TUSB_DIR_IN_MASK, _dcd.control.in_bytes, XFER_RESULT_SUCCESS, true);
  }

  LPC_USB->USBEpIntClr = ep_int_status; // acknowledge interrupt TODO cannot immediately acknowledge setup packet
}

void hal_dcd_isr(uint8_t rhport)
{
  uint32_t const dev_int_status = LPC_USB->USBDevIntSt & LPC_USB->USBDevIntEn;
  LPC_USB->USBDevIntClr = dev_int_status;// Acknowledge handled interrupt

  // Bus event
  if (dev_int_status & DEV_INT_DEVICE_STATUS_MASK)
  {
    uint8_t const dev_status = sie_read(SIE_CMDCODE_DEVICE_STATUS, 1);
    if (dev_status & SIE_DEV_STATUS_RESET_MASK)
    {
      bus_reset();
      dcd_event_bus_signal(rhport, DCD_EVENT_BUS_RESET, true);
    }

    if (dev_status & SIE_DEV_STATUS_CONNECT_CHANGE_MASK)
    {
      // device is disconnected, require using VBUS (P1_30)
      dcd_event_bus_signal(rhport, DCD_EVENT_UNPLUGGED, true);
    }

    if (dev_status & SIE_DEV_STATUS_SUSPEND_CHANGE_MASK)
    {
      if (dev_status & SIE_DEV_STATUS_SUSPEND_MASK)
      {
        dcd_event_bus_signal(rhport, DCD_EVENT_SUSPENDED, true);
      }
//        else
//      { // resume signal
//        dcd_event_bus_signal(rhport, DCD_EVENT_RESUME, true);
//      }
//    }
    }
  }

  // Control Endpoint
  if (dev_int_status & DEV_INT_ENDPOINT_SLOW_MASK)
  {
    control_xfer_isr(rhport);
  }

  // Non-Control Endpoint (DMA Mode)
  uint32_t const dma_int_status = LPC_USB->USBDMAIntSt & LPC_USB->USBDMAIntEn;

  if (dma_int_status & DMA_INT_END_OF_XFER_MASK)
  {
    uint32_t const eot_int = LPC_USB->USBEoTIntSt;
    LPC_USB->USBEoTIntClr = eot_int; // acknowledge interrupt source

    normal_xfer_isr(rhport, eot_int);
  }

  if ( (dev_int_status & DEV_INT_ERROR_MASK) || (dma_int_status & DMA_INT_ERROR_MASK) )
  {
    uint32_t error_status = sie_read(SIE_CMDCODE_READ_ERROR_STATUS, 1);
    (void) error_status;
//    TU_ASSERT(false, (void) 0);
  }
}

#endif