wd_misc.c

嵌入式文件系统 ucfs.包含全部源代码

/*
**********************************************************************
*                          Micrium, Inc.
*                      949 Crestview Circle
*                     Weston,  FL 33327-1848
*
*                            uC/FS
*
*             (c) Copyright 2001 - 2003, Micrium, Inc.
*                      All rights reserved.
*
***********************************************************************

----------------------------------------------------------------------
File        : wd_misc.c
Purpose     : Device Driver using Windows I/O function for logical sector
              access.
---------------------------END-OF-HEADER------------------------------
*/

/*********************************************************************
*
*             #include Section
*
**********************************************************************
*/

#include "fs_dev.h" 
#include "fs_lbl.h" 
#include "FS_ConfDefaults.h"        /* FS Configuration */
#include "fs_api.h"
#include "fs_clib.h"

#if FS_USE_WINDRIVE_DRIVER

#ifndef _WIN32
#error Driver requires Windows API
#endif /* _WIN32 */

#include <windows.h>
#include <winioctl.h>

/*********************************************************************
*
*             Local data types
*
**********************************************************************
*/



/*********************************************************************
*
*             Local variables        
*
**********************************************************************
*/

static HANDLE             _hDrive           [FS_WD_MAXDEV];


/*********************************************************************
*
*             Local functions
*
**********************************************************************
*/

/*********************************************************************
*
*       _InitMedium
*
*  Description:
*    Initializes the medium.
*    In this driver, this simply means opening the device.
*
*  Parameters:
*    Unit        - Unit number.
* 
*  Return value:
*    
*/
static void _InitMedium(FS_U8 Unit) {
  if (_hDrive[Unit] == INVALID_HANDLE_VALUE) {
    _hDrive[Unit] = CreateFile(Unit ? FS_WD_DEV1NAME : FS_WD_DEV0NAME, 
                                  GENERIC_READ    | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE,
                                  NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
  }
}
/*********************************************************************
*
*          _GetStatus
*
*  Description:
*    FS driver function. Get status of the media.
*
*  Parameters:
*    Unit                  - Device number.
* 
*  Return value:
*    FS_MEDIA_STATEUNKNOWN if the state of the media is unknown.
*    FS_MEDIA_ISNOTPRESENT if no card is present.
*    FS_MEDIA_ISPRESENT if a card is present.
*/
static int _GetStatus(FS_U8 Unit) {
  if (_hDrive[Unit] == INVALID_HANDLE_VALUE) {
    _InitMedium(Unit);
  }
  return (_hDrive[Unit] == INVALID_HANDLE_VALUE) ? FS_MEDIA_ISNOTPRESENT : FS_MEDIA_ISPRESENT;
}


/*********************************************************************
*
*       _ReadBurst
*
*  Description:
*    FS driver function. Write sector to the media.
*
*  Parameters:
*    Unit    - Device number.
*    Sector      - Sector to be read from the device.
*    pBuffer     - Pointer to data.
* 
*  Return value:
*    ==0         - Sector has been written to the device.
*    <0          - An error has occured.
*/

static int _ReadBurst(FS_U8 Unit, FS_U32 SectorNo, FS_U32 NumSectors, void *pBuffer) {
  FS_U32 NumBytesTransfered;
  FS_U32 NumBytes;
  LARGE_INTEGER FilePos;

  NumBytes = FS_SEC_SIZE * NumSectors;
  FilePos.QuadPart     = (__int64)SectorNo * (__int64)FS_SEC_SIZE; 

  SetFilePointer(_hDrive[Unit], FilePos.LowPart, &FilePos.HighPart, FILE_BEGIN);
  ReadFile(_hDrive[Unit], pBuffer, NumBytes, &NumBytesTransfered, NULL);
  return (NumBytesTransfered == NumBytes) ? 0 : -1;
}

/*********************************************************************
*
*       _WriteBurst
*
*  Description:
*    FS driver function. Write sector to the media.
*
*  Parameters:
*    Unit    - Device number.
*    Sector      - Sector to be written to the device.
*    pBuffer     - Pointer to data to be stored.
* 
*  Return value:
*    ==0         - Sector has been written to the device.
*    <0          - An error has occured.
*/

static int _WriteBurst(FS_U8 Unit, FS_U32 SectorNo, FS_U32 NumSectors, const void *pBuffer) {
  FS_U32 NumBytesTransfered;
  FS_U32 NumBytes;
  LARGE_INTEGER FilePos;

  NumBytes = FS_SEC_SIZE * NumSectors;
  FilePos.QuadPart     = (__int64)SectorNo * (__int64)FS_SEC_SIZE; 

  SetFilePointer(_hDrive[Unit], FilePos.LowPart, &FilePos.HighPart, FILE_BEGIN);
  WriteFile(_hDrive[Unit], pBuffer, NumBytes, &NumBytesTransfered, NULL);
  return (NumBytesTransfered == NumBytes) ? 0 : -1;
}

/*********************************************************************
*
*       _Read
*
*  Description:
*    FS driver function. Read a sector from the media.
*
*  Parameters:
*    Unit    - Device number.
*    Sector      - Sector to be read from the device.
*    pBuffer     - Pointer to buffer for storing the data.
* 
*  Return value:
*    ==0         - Sector has been read and copied to pBuffer.
*    <0          - An error has occured.
*/

static int _Read(FS_U8 Unit, FS_U32 Sector, void *pBuffer) {
  return _ReadBurst(Unit, Sector, 1, pBuffer);
}


/*********************************************************************
*
*       _Write
*
*  Description:
*    FS driver function. Write sector to the media.
*
*  Parameters:
*    Unit    - Device number.
*    Sector      - Sector to be written to the device.
*    pBuffer     - Pointer to data to be stored.
* 
*  Return value:
*    ==0         - Sector has been written to the device.
*    <0          - An error has occured.
*/
static int _Write(FS_U8 Unit, FS_U32 Sector, void *pBuffer) {
  return _WriteBurst(Unit, Sector, 1, pBuffer);
}

/*********************************************************************
*
*       _IoCtl
*
*  Description:
*    FS driver function. Execute device command.
*
*  Parameters:
*    Unit        - Unit number.
*    Cmd         - Command to be executed.
*    Aux         - Parameter depending on command.
*    pBuffer     - Pointer to a buffer used for the command.
* 
*  Return value:
*    Command specific. In general a negative value means an error.
*/
static int _IoCtl(FS_U8 Unit, FS_I32 Cmd, FS_I32 Aux, void *pBuffer) {
  FS_DEV_INFO *pInfo;
  FS_U32 NumCylinders;
  FS_U32 NumSectors;

  FS_USE_PARA(Aux);
  switch (Cmd) {
  case FS_CMD_GET_DEVINFO:
    if (pBuffer) {
      DISK_GEOMETRY DiskGeometry;
      DWORD Size;
      _InitMedium(Unit);
      Size = sizeof(DiskGeometry);
      DeviceIoControl(_hDrive[Unit], IOCTL_DISK_GET_DRIVE_GEOMETRY, NULL, 0, &DiskGeometry, Size, &Size, NULL);
      pInfo = (FS_DEV_INFO *)pBuffer;
      NumCylinders = (FS_U32)DiskGeometry.Cylinders.QuadPart;
      if (DiskGeometry.SectorsPerTrack == 63) {
        /* Some media report inaccurate values (MMC/SD).
         * Since we can not read the Number of sectors from the card info structure, we have to estimate: -6%
         */
        NumCylinders = (NumCylinders + 1) & ~1;
        NumSectors = NumCylinders * DiskGeometry.SectorsPerTrack * DiskGeometry.TracksPerCylinder;
        NumSectors = (FS_U32)(((__int64)NumSectors * 94) / 100);
      } else {
        NumSectors = NumCylinders * DiskGeometry.SectorsPerTrack * DiskGeometry.TracksPerCylinder;
      }
      pInfo->NumSectors      = NumSectors;
      pInfo->BytesPerSector  = (FS_U16)DiskGeometry.BytesPerSector;
      pInfo->NumHeads        = (FS_U16)DiskGeometry.TracksPerCylinder;
      pInfo->SectorsPerTrack = (FS_U16)DiskGeometry.SectorsPerTrack;

      return 0;
    }
    break;
  }
  return -1;
}

/*********************************************************************
*
*       _InitDevice
*
*  Description:
*    Initializes the device.
*    In this driver, this simply means marking the handle as invalid.
*
*  Parameters:
*    Unit        - Unit number.
* 
*  Return value:
*    
*/
static int _InitDevice(FS_U8 Unit) {
  _hDrive[Unit] = INVALID_HANDLE_VALUE;
  return 0;
}

/*********************************************************************
*
*             Global variables        
*
**********************************************************************
*/

const FS_DEVICE_TYPE FS__windrive_driver = {
  "windrv",
  FS_WD_MAXDEV,
  _GetStatus,
  _Read,
  _Write,
  _IoCtl,
  _ReadBurst,
  _WriteBurst,
  _InitDevice,
  _InitMedium
};

#endif /* END OF FS_USE_WINDRIVE_DRIVER */

/*************************** End of file ****************************/