10b73ce30SBin Meng /* 20b73ce30SBin Meng * CRC16 (CCITT) Checksum Algorithm 30b73ce30SBin Meng * 40b73ce30SBin Meng * Copyright (c) 2021 Wind River Systems, Inc. 50b73ce30SBin Meng * 60b73ce30SBin Meng * Author: 70b73ce30SBin Meng * Bin Meng <bin.meng@windriver.com> 80b73ce30SBin Meng * 90b73ce30SBin Meng * From Linux kernel v5.10 include/linux/crc-ccitt.h 100b73ce30SBin Meng * 110b73ce30SBin Meng * SPDX-License-Identifier: GPL-2.0 120b73ce30SBin Meng */ 130b73ce30SBin Meng 149c092804SMarkus Armbruster #ifndef CRC_CCITT_H 159c092804SMarkus Armbruster #define CRC_CCITT_H 160b73ce30SBin Meng 170b73ce30SBin Meng extern uint16_t const crc_ccitt_table[256]; 180b73ce30SBin Meng extern uint16_t const crc_ccitt_false_table[256]; 190b73ce30SBin Meng 20*f703f1efSPhilippe Mathieu-Daudé uint16_t crc_ccitt(uint16_t crc, const uint8_t *buffer, size_t len); 21*f703f1efSPhilippe Mathieu-Daudé uint16_t crc_ccitt_false(uint16_t crc, const uint8_t *buffer, size_t len); 220b73ce30SBin Meng crc_ccitt_byte(uint16_t crc,const uint8_t c)230b73ce30SBin Mengstatic inline uint16_t crc_ccitt_byte(uint16_t crc, const uint8_t c) 240b73ce30SBin Meng { 250b73ce30SBin Meng return (crc >> 8) ^ crc_ccitt_table[(crc ^ c) & 0xff]; 260b73ce30SBin Meng } 270b73ce30SBin Meng crc_ccitt_false_byte(uint16_t crc,const uint8_t c)280b73ce30SBin Mengstatic inline uint16_t crc_ccitt_false_byte(uint16_t crc, const uint8_t c) 290b73ce30SBin Meng { 300b73ce30SBin Meng return (crc << 8) ^ crc_ccitt_false_table[(crc >> 8) ^ c]; 310b73ce30SBin Meng } 320b73ce30SBin Meng 339c092804SMarkus Armbruster #endif /* CRC_CCITT_H */ 34