/*
 * 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;
	}
}
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;
	}
}
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;
}
EXPORT_SYMBOL(crc8);

MODULE_DESCRIPTION("CRC8 (by Williams, Ross N.) function");
MODULE_AUTHOR("Broadcom Corporation");
MODULE_LICENSE("Dual BSD/GPL");
t type='hidden' name='id' value='7ca00409b5bd6e79a03d1cf3982dc429f371c02b'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/log/?h=nds-private-remove&amp;id=7ca00409b5bd6e79a03d1cf3982dc429f371c02b'>root</a>/<a href='/cgit.cgi/linux/net-next.git/log/net?h=nds-private-remove&amp;id=7ca00409b5bd6e79a03d1cf3982dc429f371c02b'>net</a>/<a href='/cgit.cgi/linux/net-next.git/log/net/wireless?h=nds-private-remove&amp;id=7ca00409b5bd6e79a03d1cf3982dc429f371c02b'>wireless</a>/<a href='/cgit.cgi/linux/net-next.git/log/net/wireless/debugfs.c?h=nds-private-remove&amp;id=7ca00409b5bd6e79a03d1cf3982dc429f371c02b'>debugfs.c</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/cgit.cgi/linux/net-next.git/log/net/wireless/debugfs.c?h=nds-private-remove&amp;id=7ca00409b5bd6e79a03d1cf3982dc429f371c02b&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th><th class='left'>Files</th><th class='left'>Lines</th></tr>