crc8.c 411 B

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  1. /*
  2. * Copyright (c) 2013 Google, Inc
  3. *
  4. * SPDX-License-Identifier: GPL-2.0+
  5. */
  6. #include "linux/crc8.h"
  7. unsigned int crc8(const unsigned char *vptr, int len)
  8. {
  9. const unsigned char *data = vptr;
  10. unsigned int crc = 0;
  11. int i, j;
  12. for (j = len; j; j--, data++) {
  13. crc ^= (*data << 8);
  14. for (i = 8; i; i--) {
  15. if (crc & 0x8000)
  16. crc ^= (0x1070 << 3);
  17. crc <<= 1;
  18. }
  19. }
  20. return (crc >> 8) & 0xff;
  21. }