33 lines
492 B
C
33 lines
492 B
C
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/*
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* Copyright (c) 2013 Google, Inc
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*
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* SPDX-License-Identifier: GPL-2.0+
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*/
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#include "linux/crc8.h"
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#define POLY (0x1070U << 3)
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static unsigned char _crc8(unsigned short data)
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{
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int i;
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for (i = 0; i < 8; i++) {
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if (data & 0x8000)
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data = data ^ POLY;
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data = data << 1;
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}
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return (unsigned char)(data >> 8);
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}
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unsigned int crc8(unsigned int crc, const unsigned char *vptr, int len)
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{
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int i;
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for (i = 0; i < len; i++)
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crc = _crc8((crc ^ vptr[i]) << 8);
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return crc;
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}
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