cregit-Linux how code gets into the kernel

Release 4.14 lib/crc8.c

Directory: lib
/*
 * Copyright (c) 2011 Broadcom Corporation
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */


#define pr_fmt(fmt)		KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/crc8.h>
#include <linux/printk.h>

/*
 * crc8_populate_msb - fill crc table for given polynomial in reverse bit order.
 *
 * table:       table to be filled.
 * polynomial:  polynomial for which table is to be filled.
 */

void crc8_populate_msb(u8 table[CRC8_TABLE_SIZE], u8 polynomial) { int i, j; const u8 msbit = 0x80; u8 t = msbit; table[0] = 0; for (i = 1; i < CRC8_TABLE_SIZE; i *= 2) { t = (t << 1) ^ (t & msbit ? polynomial : 0); for (j = 0; j < i; j++) table[i+j] = table[j] ^ t; } }

Contributors

PersonTokensPropCommitsCommitProp
Arend Van Spriel98100.00%1100.00%
Total98100.00%1100.00%

EXPORT_SYMBOL(crc8_populate_msb); /* * crc8_populate_lsb - fill crc table for given polynomial in regular bit order. * * table: table to be filled. * polynomial: polynomial for which table is to be filled. */
void crc8_populate_lsb(u8 table[CRC8_TABLE_SIZE], u8 polynomial) { int i, j; u8 t = 1; table[0] = 0; for (i = (CRC8_TABLE_SIZE >> 1); i; i >>= 1) { t = (t >> 1) ^ (t & 1 ? polynomial : 0); for (j = 0; j < CRC8_TABLE_SIZE; j += 2*i) table[i+j] = table[j] ^ t; } }

Contributors

PersonTokensPropCommitsCommitProp
Arend Van Spriel97100.00%1100.00%
Total97100.00%1100.00%

EXPORT_SYMBOL(crc8_populate_lsb); /* * crc8 - calculate a crc8 over the given input data. * * table: crc table used for calculation. * pdata: pointer to data buffer. * nbytes: number of bytes in data buffer. * crc: previous returned crc8 value. */
u8 crc8(const u8 table[CRC8_TABLE_SIZE], u8 *pdata, size_t nbytes, u8 crc) { /* loop over the buffer data */ while (nbytes-- > 0) crc = table[(crc ^ *pdata++) & 0xff]; return crc; }

Contributors

PersonTokensPropCommitsCommitProp
Arend Van Spriel48100.00%1100.00%
Total48100.00%1100.00%

EXPORT_SYMBOL(crc8); MODULE_DESCRIPTION("CRC8 (by Williams, Ross N.) function"); MODULE_AUTHOR("Broadcom Corporation"); MODULE_LICENSE("Dual BSD/GPL");

Overall Contributors

PersonTokensPropCommitsCommitProp
Arend Van Spriel293100.00%1100.00%
Total293100.00%1100.00%
Directory: lib
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.