Re: [RFC][WORTH IT?][PATCH] bcma: make use of crc8 lib

["Arend van Spriel" <arend@broadcom.com>]

On 06/15/2011 02:09 PM, Arend van Spriel wrote:
> On 06/15/2011 01:53 PM, Rafał Miłecki wrote:
>>    static u8 bcma_sprom_crc(const u16 *sprom)
>>    {
>> -	int word;
>> -	u8 crc = 0xFF;
>> +	u8 crc;
>> +	u8 sprom2[SSB_SPROMSIZE_WORDS_R4 * 2 - 1];
>> +	u8 table[CRC8_TABLE_SIZE];
>> +	u16 word;
>>
>> +	/* u16 to u8 */
>>    	for (word = 0; word<   SSB_SPROMSIZE_WORDS_R4 - 1; word++) {
>> -		crc = bcma_crc8(crc, sprom[word]&   0x00FF);
>> -		crc = bcma_crc8(crc, (sprom[word]&   0xFF00)>>   8);
>> +		sprom2[word * 2] = sprom[word]&   0x00FF;
>> +		sprom2[(word * 2) + 1] = (sprom[word]&   0xFF00)>>   8;
>>    	}
>> -	crc = bcma_crc8(crc, sprom[SSB_SPROMSIZE_WORDS_R4 - 1]&   0x00FF);
>> +	/* 127th byte */
>> +	sprom2[(SSB_SPROMSIZE_WORDS_R4 * 2) - 2] =
>> +				sprom[SSB_SPROMSIZE_WORDS_R4 - 1]&   0x00FF;
>> +
>> +	/* Prepare table, 0xAB is x^8 + x^7 + x^6 + x^4 + x^2 + 1 */
>> +	crc8_populate_lsb(table, 0xAB);
>> +
>> +	/* Calculate */
>> +	crc = crc8(table, sprom2, (SSB_SPROMSIZE_WORDS_R4 * 2) - 1, 0xFF);
>>    	crc ^= 0xFF;
>>
>>    	return crc;
> You could do (I think):
>
> crc8_populate_lsb(table, 0xAB);
> for (word = 0; word<   SSB_SPROMSIZE_WORDS_R4; word++) {
> 	u16 val = cpu_to_le16(sprom[word]);
> 	crc = crc8(table,&val, sizeof(u16), crc);
Obviously this should have proper cast here so: (u8 *)&val

Gr. AvS

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