LXR linux/include/linux/crc-itu-t.h

   1/* SPDX-License-Identifier: GPL-2.0-only */
   2/*
   3 *      crc-itu-t.h - CRC ITU-T V.41 routine
   4 *
   5 * Implements the standard CRC ITU-T V.41:
   6 *   Width 16
   7 *   Poly  0x1021 (x^16 + x^12 + x^15 + 1)
   8 *   Init  0
   9 */
  10
  11#ifndef CRC_ITU_T_H
  12#define CRC_ITU_T_H
  13
  14#include <linux/types.h>
  15
  16extern u16 const crc_itu_t_table[256];
  17
  18extern u16 crc_itu_t(u16 crc, const u8 *buffer, size_t len);
  19
  20static inline u16 crc_itu_t_byte(u16 crc, const u8 data)
  21{
  22        return (crc << 8) ^ crc_itu_t_table[((crc >> 8) ^ data) & 0xff];
  23}
  24
  25#endif /* CRC_ITU_T_H */
  26
  27