xref: /openbmc/u-boot/lib/crc8.c (revision 4a2b2724)
1 /*
2  * Copyright (c) 2013 Google, Inc
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include "linux/crc8.h"
8 
9 #define POLY	(0x1070U << 3)
10 
11 static unsigned char _crc8(unsigned short data)
12 {
13 	int i;
14 
15 	for (i = 0; i < 8; i++) {
16 		if (data & 0x8000)
17 			data = data ^ POLY;
18 		data = data << 1;
19 	}
20 
21 	return (unsigned char)(data >> 8);
22 }
23 
24 unsigned int crc8(unsigned int crc, const unsigned char *vptr, int len)
25 {
26 	int i;
27 
28 	for (i = 0; i < len; i++)
29 		crc = _crc8((crc ^ vptr[i]) << 8);
30 
31 	return crc;
32 }
33