drivers/staging/vt6656/tether.c

   1 /*
   2  * Copyright (c) 2003 VIA Networking, Inc. All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  *
  18  *
  19  * File: tether.c
  20  *
  21  * Purpose:
  22  *
  23  * Author: Tevin Chen
  24  *
  25  * Date: May 21, 1996
  26  *
  27  * Functions:
  28  *      ETHbIsBufferCrc32Ok - Check CRC value of the buffer if Ok or not
  29  *
  30  * Revision History:
  31  *
  32  */
  33
  34 #include "device.h"
  35 #include "tmacro.h"
  36 #include "tcrc.h"
  37 #include "tether.h"
  38
  39 /*
  40  * Description: Check CRC value of the buffer if Ok or not
  41  *
  42  * Parameters:
  43  *  In:
  44  *              pbyBuffer           - pointer of buffer (normally is rx buffer)
  45  *              cbFrameLength   - length of buffer, including CRC portion
  46  *  Out:
  47  *      none
  48  *
  49  * Return Value: true if ok; false if error.
  50  *
  51  */
  52 bool ETHbIsBufferCrc32Ok(u8 * pbyBuffer, unsigned int cbFrameLength)
  53 {
  54         u32 dwCRC;
  55
  56         dwCRC = CRCdwGetCrc32(pbyBuffer, cbFrameLength - 4);
  57         if (cpu_to_le32(*((u32 *)(pbyBuffer + cbFrameLength - 4))) != dwCRC)
  58                 return false;
  59         return true;
  60 }
  61