/*----------------------------------------------------------------------------
 *      U S B  -  K e r n e l
 *----------------------------------------------------------------------------
 *      Name:    MSCUSER.C
 *      Purpose: Mass Storage Class Custom User Module
 *      Version: V1.10
 *----------------------------------------------------------------------------
 *      This software is supplied "AS IS" without any warranties, express,
 *      implied or statutory, including but not limited to the implied
 *      warranties of fitness for purpose, satisfactory quality and
 *      noninfringement. Keil extends you a royalty-free right to reproduce
 *      and distribute executable files created using this software for use
 *      on NXP Semiconductors LPC family microcontroller devices only. Nothing
 *      else gives you the right to use this software.
 *
 *      Copyright (c) 2005-2009 Keil Software.
 *---------------------------------------------------------------------------*/

extern "C" {
#include "LPC17xx.h"
#include "lpc_types.h"
}
#include "usb.h"
#include "msc.h"
#include "usbcfg.h"
#include "usbhw.h"
#include "usbcore.h"
#include "mscuser.h"

#include "../chanfs/diskio.h"
#include <debug_frmwrk.h>

DWORD MSC_BlockCount = 0;

uint32_t MemOK;                   /* Memory OK */

DWORD lba;                        /* start block */
DWORD transfer_count;             /* blocks to transfer */
DWORD length;
uint32_t block_offset;            /* current block offset*/

uint8_t  BulkStage;               /* Bulk Stage */

uint8_t  BulkBuf[MSC_MAX_PACKET]; /* Bulk In/Out Buffer */
uint8_t  block_cache[MSC_BLOCK_SIZE];
uint8_t  BulkLen;                 /* Bulk In/Out Length */

MSC_CBW CBW;                   /* Command Block Wrapper */
MSC_CSW CSW;                   /* Command Status Wrapper */
uint8_t media_lock = 0;

uint32_t MSC_SD_Lock() {
  media_lock = CBW.CB[4]; //0x1 - lock, 0x0 - unlock
  // logical_unit = CBW.CB[1] & 0xE0;
  CSW.bStatus = CSW_CMD_PASSED;
  MSC_SetCSW();
  return 0;
}

uint32_t MSC_SD_Release(uint8_t pdrv) {
  MSC_BlockCount = 0;
  return 0;
}

uint32_t MSC_SD_Init(uint8_t pdrv) {
  DSTATUS ret = disk_initialize(pdrv);
  if(ret) return ret;
  if(disk_ioctl (pdrv, GET_SECTOR_COUNT, (void *)(&MSC_BlockCount))) return 1;
  return 0;
}

#define STARTSTOP_STOPMOTOR        0x0
#define STARTSTOP_STARTMOTOR       0x1
#define STARTSTOP_EJECT            0x2
#define STARTSTOP_LOAD             0x3

void MSC_StartStopUnit() {
  switch (CBW.CB[4] & 0x03) {
    case STARTSTOP_EJECT:
      MSC_SD_Release(0);
      break;
    case STARTSTOP_LOAD:
      if(MSC_BlockCount == 0) {
        if(MSC_SD_Init(0) != 0) {
          CSW.bStatus = CSW_CMD_FAILED;
          MSC_SetCSW();
          return;
        }
      }
      break;
    default:
      _DBG("MSC_StartStopUnit unknown startstopunit sub command\n");
  }
  CSW.bStatus = CSW_CMD_PASSED;
  MSC_SetCSW();
}

/*
 *  MSC Mass Storage Reset Request Callback
 *   Called automatically on Mass Storage Reset Request
 *    Parameters:      None (global SetupPacket and EP0Buf)
 *    Return Value:    TRUE - Success, FALSE - Error
 */

uint32_t MSC_Reset (void) {
  BulkStage = MSC_BS_CBW;
  return (TRUE);
}


/*
 *  MSC Get Max LUN Request Callback
 *   Called automatically on Get Max LUN Request
 *    Parameters:      None (global SetupPacket and EP0Buf)
 *    Return Value:    TRUE - Success, FALSE - Error
 */

uint32_t MSC_GetMaxLUN (void) {

  EP0Buf[0] = 0;               /* No LUN associated with this device */
  return (TRUE);
}


/*
 *  MSC Memory Read Callback
 *   Called automatically on Memory Read Event
 *    Parameters:      None (global variables)
 *    Return Value:    None
 */

void MSC_MemoryRead (void) {
  uint32_t n = (length > MSC_MAX_PACKET) ? MSC_MAX_PACKET : length;

  if (lba > MSC_BlockCount) {
      n = (MSC_BlockCount - lba) * MSC_BLOCK_SIZE + block_offset;
      BulkStage = MSC_BS_ERROR;
  }

  if(block_offset == 0) {
    disk_read (0, block_cache, lba, 1);
  }

  USB_WriteEP(MSC_EP_IN, &block_cache[block_offset], n);

  block_offset += n;
  length -= n;
  CSW.dDataResidue -= n;

  if(block_offset >= MSC_BLOCK_SIZE) {
    block_offset = 0;
    ++lba;
  }

  if (length == 0) {
    BulkStage = MSC_BS_DATA_IN_LAST;
  }

  if (BulkStage != MSC_BS_DATA_IN) {
    CSW.bStatus = CSW_CMD_PASSED;
  }
}


/*
 *  MSC Memory Write Callback
 *   Called automatically on Memory Write Event
 *    Parameters:      None (global variables)
 *    Return Value:    None
 */

void MSC_MemoryWrite (void) {

  for (uint32_t n = 0; n < BulkLen; n++) {
    block_cache[block_offset + n] = BulkBuf[n];
  }

  if(block_offset + BulkLen >= MSC_BLOCK_SIZE) {
    if(!(disk_status(0) & STA_PROTECT)){
      disk_write(0, block_cache, lba, 1);
    }
  }

  block_offset += BulkLen;
  length -= BulkLen;
  CSW.dDataResidue -= BulkLen;

  if(block_offset >= MSC_BLOCK_SIZE) {
    block_offset = 0;
    ++lba;
  }

  if ((length == 0) || (BulkStage == MSC_BS_CSW)) {
    CSW.bStatus = CSW_CMD_PASSED;
    MSC_SetCSW();
  }
}


/*
 *  MSC Memory Verify Callback
 *   Called automatically on Memory Verify Event
 *    Parameters:      None (global variables)
 *    Return Value:    None
 */

void MSC_MemoryVerify (void) {

  if(!block_offset) {
    disk_read(0, block_cache, lba, 1);
  }

  for (uint32_t n = 0; n < BulkLen; n++) {
    if (block_cache[block_offset + n] != BulkBuf[n]) {
      MemOK = FALSE;
      break;
    }
  }

  block_offset += BulkLen;
  length -= BulkLen;
  CSW.dDataResidue -= BulkLen;

  if ((length == 0) || (BulkStage == MSC_BS_CSW)) {
    CSW.bStatus = (MemOK) ? CSW_CMD_PASSED : CSW_CMD_FAILED;
    MSC_SetCSW();
  }
}


/*
 *  MSC SCSI Read/Write Setup Callback
 *    Parameters:      None (global variables)
 *    Return Value:    TRUE - Success, FALSE - Error
 */

uint32_t MSC_RWSetup (void) {
  uint32_t n;

  /* Logical Block Address of First Block */
  lba = (CBW.CB[2] << 24) |
        (CBW.CB[3] << 16) |
        (CBW.CB[4] <<  8) |
        (CBW.CB[5] <<  0);

  /* Number of Blocks to transfer */
  transfer_count = (CBW.CB[7] <<  8) |
                   (CBW.CB[8] <<  0);

  block_offset = 0;
  length = transfer_count * MSC_BLOCK_SIZE;

  if (CBW.dDataLength != (transfer_count * MSC_BLOCK_SIZE)) {
    USB_SetStallEP(MSC_EP_IN);
    USB_SetStallEP(MSC_EP_OUT);
    CSW.bStatus = CSW_PHASE_ERROR;
    MSC_SetCSW();
    return (FALSE);
  }

  return (TRUE);
}


/*
 *  Check Data IN Format
 *    Parameters:      None (global variables)
 *    Return Value:    TRUE - Success, FALSE - Error
 */

uint32_t DataInFormat (void) {

  if (CBW.dDataLength == 0) {
    CSW.bStatus = CSW_PHASE_ERROR;
    MSC_SetCSW();
    return (FALSE);
  }
  if ((CBW.bmFlags & 0x80) == 0) {
    USB_SetStallEP(MSC_EP_OUT);
    CSW.bStatus = CSW_PHASE_ERROR;
    MSC_SetCSW();
    return (FALSE);
  }
  return (TRUE);
}


/*
 *  Perform Data IN Transfer
 *    Parameters:      None (global variables)
 *    Return Value:    TRUE - Success, FALSE - Error
 */

void DataInTransfer (void) {

  if (BulkLen > CBW.dDataLength) {
    BulkLen = CBW.dDataLength;
  }

  USB_WriteEP(MSC_EP_IN, BulkBuf, BulkLen);
  BulkStage = MSC_BS_DATA_IN_LAST;

  CSW.dDataResidue -= BulkLen;
  CSW.bStatus = CSW_CMD_PASSED;
}


/*
 *  MSC SCSI Test Unit Ready Callback
 *    Parameters:      None (global variables)
 *    Return Value:    None
 */

void MSC_TestUnitReady (void) {

  if (CBW.dDataLength != 0) {
    if ((CBW.bmFlags & 0x80) != 0) {
      USB_SetStallEP(MSC_EP_IN);
    } else {
      USB_SetStallEP(MSC_EP_OUT);
    }
  }

  if(MSC_BlockCount > 0) {
    CSW.bStatus = CSW_CMD_PASSED;
  } else {
    CSW.bStatus = CSW_CMD_FAILED;
  }

  MSC_SetCSW();
}


/*
 *  MSC SCSI Request Sense Callback
 *    Parameters:      None (global variables)
 *    Return Value:    None
 */

void MSC_RequestSense (void) {

  if (!DataInFormat()) return;

  BulkBuf[ 0] = 0x70;          /* Response Code */
  BulkBuf[ 1] = 0x00;
  BulkBuf[ 2] = static_cast<uint8_t>(Sense_KEY::ILLEGAL_REQUEST);
  BulkBuf[ 3] = 0x00;
  BulkBuf[ 4] = 0x00;
  BulkBuf[ 5] = 0x00;
  BulkBuf[ 6] = 0x00;
  BulkBuf[ 7] = 0x0A;           /* Additional Length */

  BulkBuf[ 8] = 0x00;
  BulkBuf[ 9] = 0x00;
  BulkBuf[10] = 0x00;
  BulkBuf[11] = 0x00;
  BulkBuf[12] = static_cast<uint8_t>(Sense_ASC::CANNOT_READ_MEDIUM);
  BulkBuf[13] = static_cast<uint8_t>(Sense_ASCQ::UNKNOWN_FORMAT);
  BulkBuf[14] = 0x00;
  BulkBuf[15] = 0x00;
  BulkBuf[16] = 0x00;
  BulkBuf[17] = 0x00;

  if (MSC_BlockCount == 0) {
    BulkBuf[ 2] = static_cast<uint8_t>(Sense_KEY::NOT_READY);
    BulkBuf[12] = static_cast<uint8_t>(Sense_ASC::MEDIUM_NOT_PRESENT);
    BulkBuf[13] = static_cast<uint8_t>(Sense_ASCQ::LOADABLE);
  }

  BulkLen = 18;
  DataInTransfer();
}


/*
 *  MSC SCSI Inquiry Callback
 *  Parameters:      None (global variables)
 *  Return Value:    None
 */

void MSC_Inquiry (void) {

  if (!DataInFormat()) return;

  BulkBuf[ 0] = 0x00;          /* Direct Access Device */
  BulkBuf[ 1] = 0x80;          /* RMB = 1: Removable Medium */
  BulkBuf[ 2] = 0x00;          /* Version: No conformance claim to standard */
  BulkBuf[ 3] = 0x01;

  BulkBuf[ 4] = 36-4;          /* Additional Length */
  BulkBuf[ 5] = 0x80;          /* SCCS = 1: Storage Controller Component */
  BulkBuf[ 6] = 0x00;
  BulkBuf[ 7] = 0x00;

  BulkBuf[ 8] = 'M';           /* Vendor Identification */
  BulkBuf[ 9] = 'a';
  BulkBuf[10] = 'r';
  BulkBuf[11] = 'l';
  BulkBuf[12] = 'i';
  BulkBuf[13] = 'n';
  BulkBuf[14] = ' ';
  BulkBuf[15] = ' ';

  BulkBuf[16] = 'R';           /* Product Identification */
  BulkBuf[17] = 'e';
  BulkBuf[18] = '-';
  BulkBuf[19] = 'A';
  BulkBuf[20] = 'R';
  BulkBuf[21] = 'M';
  BulkBuf[22] = ' ';
  BulkBuf[23] = 'S';
  BulkBuf[24] = 'D';
  BulkBuf[25] = 'C';
  BulkBuf[26] = 'a';
  BulkBuf[27] = 'r';
  BulkBuf[28] = 'd';
  BulkBuf[29] = ' ';
  BulkBuf[30] = '0';
  BulkBuf[31] = '1';

  BulkBuf[32] = '1';           /* Product Revision Level */
  BulkBuf[33] = '.';
  BulkBuf[34] = '0';
  BulkBuf[35] = ' ';

  if(MSC_BlockCount == 0) {
    BulkBuf[0] = 0x20; // Direct Access Device usually available but not currently
  }

  BulkLen = 36;
  DataInTransfer();
}


/*
 *  MSC SCSI Mode Sense (6-Byte) Callback
 *    Parameters:      None (global variables)
 *    Return Value:    None
 */

void MSC_ModeSense6 (void) {

  if (!DataInFormat()) return;

  BulkBuf[ 0] = 0x03;
  BulkBuf[ 1] = 0x00;
  BulkBuf[ 2] = 0x00;
  BulkBuf[ 3] = 0x00;

  BulkLen = 4;
  DataInTransfer();
}


/*
 *  MSC SCSI Mode Sense (10-Byte) Callback
 *    Parameters:      None (global variables)
 *    Return Value:    None
 */

void MSC_ModeSense10 (void) {

  if (!DataInFormat()) return;

  BulkBuf[ 0] = 0x00;
  BulkBuf[ 1] = 0x06;
  BulkBuf[ 2] = 0x00;
  BulkBuf[ 3] = 0x00;
  BulkBuf[ 4] = 0x00;
  BulkBuf[ 5] = 0x00;
  BulkBuf[ 6] = 0x00;
  BulkBuf[ 7] = 0x00;

  BulkLen = 8;
  DataInTransfer();
}


/*
 *  MSC SCSI Read Capacity Callback
 *    Parameters:      None (global variables)
 *    Return Value:    None
 */

void MSC_ReadCapacity (void) {

  if (!DataInFormat()) return;

  /* Last Logical Block */
  BulkBuf[ 0] = ((MSC_BlockCount - 1) >> 24) & 0xFF;
  BulkBuf[ 1] = ((MSC_BlockCount - 1) >> 16) & 0xFF;
  BulkBuf[ 2] = ((MSC_BlockCount - 1) >>  8) & 0xFF;
  BulkBuf[ 3] = ((MSC_BlockCount - 1) >>  0) & 0xFF;

  /* Block Length */
  BulkBuf[ 4] = (MSC_BLOCK_SIZE >> 24) & 0xFF;
  BulkBuf[ 5] = (MSC_BLOCK_SIZE >> 16) & 0xFF;
  BulkBuf[ 6] = (MSC_BLOCK_SIZE >>  8) & 0xFF;
  BulkBuf[ 7] = (MSC_BLOCK_SIZE >>  0) & 0xFF;

  BulkLen = 8;
  DataInTransfer();
}


/*
 *  MSC SCSI Read Format Capacity Callback
 *    Parameters:      None (global variables)
 *    Return Value:    None
 */

void MSC_ReadFormatCapacity (void) {

  if (!DataInFormat()) return;

  BulkBuf[ 0] = 0x00;
  BulkBuf[ 1] = 0x00;
  BulkBuf[ 2] = 0x00;
  BulkBuf[ 3] = 0x08;          /* Capacity List Length */

  /* Block Count */
  BulkBuf[ 4] = (MSC_BlockCount >> 24) & 0xFF;
  BulkBuf[ 5] = (MSC_BlockCount >> 16) & 0xFF;
  BulkBuf[ 6] = (MSC_BlockCount >>  8) & 0xFF;
  BulkBuf[ 7] = (MSC_BlockCount >>  0) & 0xFF;

  /* Block Length */
  BulkBuf[ 8] = 0x02;          /* Descriptor Code: Formatted Media */
  BulkBuf[ 9] = (MSC_BLOCK_SIZE >> 16) & 0xFF;
  BulkBuf[10] = (MSC_BLOCK_SIZE >>  8) & 0xFF;
  BulkBuf[11] = (MSC_BLOCK_SIZE >>  0) & 0xFF;

  BulkLen = 12;
  DataInTransfer();
}


/*
 *  MSC Get Command Block Wrapper Callback
 *    Parameters:      None (global variables)
 *    Return Value:    None
 */

void MSC_GetCBW (void) {
  uint32_t n;

  for (n = 0; n < BulkLen; n++) {
    *((uint8_t *)&CBW + n) = BulkBuf[n];
  }
  if ((BulkLen == sizeof(CBW)) && (CBW.dSignature == MSC_CBW_Signature)) {
    /* Valid CBW */
    CSW.dTag = CBW.dTag;
    CSW.dDataResidue = CBW.dDataLength;
    if ((CBW.bLUN != 0) || (CBW.bCBLength < 1) || CBW.bCBLength > 16) {
fail: CSW.bStatus = CSW_CMD_FAILED;
      MSC_SetCSW();
      _DBG("Failed SCSI OP code ");
      _DBH(CBW.CB[0]);
      _DBG("\n");
    } else {
      switch (CBW.CB[0]) {
        case SCSI_TEST_UNIT_READY:
          MSC_TestUnitReady();
          break;
        case SCSI_REQUEST_SENSE:
          MSC_RequestSense();
          break;
        case SCSI_FORMAT_UNIT:
          goto fail;
        case SCSI_INQUIRY:
          MSC_Inquiry();
          break;
        case SCSI_START_STOP_UNIT:
          MSC_StartStopUnit();
          break;
        case SCSI_MEDIA_REMOVAL:
          MSC_SD_Lock();
          break;
        case SCSI_MODE_SELECT6:
          goto fail;
        case SCSI_MODE_SENSE6:
          MSC_ModeSense6();
          break;
        case SCSI_MODE_SELECT10:
          goto fail;
        case SCSI_MODE_SENSE10:
          MSC_ModeSense10();
          break;
        case SCSI_READ_FORMAT_CAPACITIES:
          MSC_ReadFormatCapacity();
          break;
        case SCSI_READ_CAPACITY:
          MSC_ReadCapacity();
          break;
        case SCSI_READ10:
          if (MSC_RWSetup()) {
            if ((CBW.bmFlags & 0x80) != 0) {
              BulkStage = MSC_BS_DATA_IN;
              MSC_MemoryRead();
            } else {
              USB_SetStallEP(MSC_EP_OUT);
              CSW.bStatus = CSW_PHASE_ERROR;
              MSC_SetCSW();
            }
          }
          break;
        case SCSI_WRITE10:
          if (MSC_RWSetup()) {
            if ((CBW.bmFlags & 0x80) == 0) {
              BulkStage = MSC_BS_DATA_OUT;
            } else {
              USB_SetStallEP(MSC_EP_IN);
              CSW.bStatus = CSW_PHASE_ERROR;
              MSC_SetCSW();
            }
          }
          break;
        case SCSI_VERIFY10:
          if (MSC_RWSetup()) {
            if ((CBW.bmFlags & 0x80) == 0) {
              BulkStage = MSC_BS_DATA_OUT;
              MemOK = TRUE;
            } else {
              USB_SetStallEP(MSC_EP_IN);
              CSW.bStatus = CSW_PHASE_ERROR;
              MSC_SetCSW();
            }
          }
          break;
        default:
          goto fail;
      }
    }
  } else {
    /* Invalid CBW */
    USB_SetStallEP(MSC_EP_IN);
    USB_SetStallEP(MSC_EP_OUT);
    BulkStage = MSC_BS_ERROR;
  }
}


/*
 *  MSC Set Command Status Wrapper Callback
 *    Parameters:      None (global variables)
 *    Return Value:    None
 */

void MSC_SetCSW (void) {

  CSW.dSignature = MSC_CSW_Signature;
  USB_WriteEP(MSC_EP_IN, (uint8_t *)&CSW, sizeof(CSW));
  BulkStage = MSC_BS_CSW;
}


/*
 *  MSC Bulk In Callback
 *    Parameters:      None (global variables)
 *    Return Value:    None
 */

void MSC_BulkIn (void) {

  switch (BulkStage) {
    case MSC_BS_DATA_IN:
      switch (CBW.CB[0]) {
        case SCSI_READ10:
          MSC_MemoryRead();
          break;
      }
      break;
    case MSC_BS_DATA_IN_LAST:
      MSC_SetCSW();
      break;
    case MSC_BS_DATA_IN_LAST_STALL:
      USB_SetStallEP(MSC_EP_IN);
      MSC_SetCSW();
      break;
    case MSC_BS_CSW:
      BulkStage = MSC_BS_CBW;
      break;
  }
}


/*
 *  MSC Bulk Out Callback
 *    Parameters:      None (global variables)
 *    Return Value:    None
 */

void MSC_BulkOut (void) {

  BulkLen = (uint8_t)USB_ReadEP(MSC_EP_OUT, BulkBuf);
  switch (BulkStage) {
    case MSC_BS_CBW:
      MSC_GetCBW();
      break;
    case MSC_BS_DATA_OUT:
      switch (CBW.CB[0]) {
        case SCSI_WRITE10:
          MSC_MemoryWrite();
          break;
        case SCSI_VERIFY10:
          MSC_MemoryVerify();
          break;
      }
      break;
    default:
      USB_SetStallEP(MSC_EP_OUT);
      CSW.bStatus = CSW_PHASE_ERROR;
      MSC_SetCSW();
      break;
  }
}