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/* Copyright 2014 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*
* Very simple 8-bit CRC function.
*/
#ifndef __CROS_EC_CRC8_H
#define __CROS_EC_CRC8_H
/**
* crc8
* Return CRC-8 of the data, using x^8 + x^2 + x + 1 polynomial. A table-based
* algorithm would be faster, but for only a few bytes it isn't worth the code
* size.
* @param data uint8_t *, input, a pointer to input data
* @param len int, input, size of input data in bytes
* @return the crc-8 of the input data.
*/
uint8_t crc8(const uint8_t *data, int len);
/**
* crc8_arg
* Return CRC-8 of the data, based upon pre-calculated partial CRC of previous
* data.
* @param data uint8_t *, input, a pointer to input data
* @param len int, input, size of input data in bytes
* @param previous_crc uint8_t, input, pre-calculated CRC of previous data.
* Seed with zero for a new calculation (or use the result of crc8()).
* @return the crc-8 of the input data.
*/
uint8_t crc8_arg(const uint8_t *data, int len, uint8_t previous_crc);
#endif /* __CROS_EC_CRC8_H */