Re: [PATCH] CRC ITU-T V.41

["Randy.Dunlap" <rdunlap@xenotime.net>]

On Mon, 12 Jun 2006 16:17:04 +0200 Ivo van Doorn wrote:

> This will add the CRC calculation according
> to the CRC ITU-T V.41 to the kernel lib/ folder.
> 
> This code has been derived from the rt2x00 driver,
> currently found only in the wireless-dev tree, but
> this library is generic and could be used by more
> drivers who currently use their own implementation.

so the rt2x00 driver will be converted to use this lib/ code?

> Signed-off-by Ivo van Doorn <IvDoorn@gmail.com>
> ---
> 
> diff --git a/include/linux/crc-itu-t.h b/include/linux/crc-itu-t.h
> new file mode 100644
> index 0000000..84920f3
> --- /dev/null
> +++ b/include/linux/crc-itu-t.h
> @@ -0,0 +1,28 @@
> +/*
> + *	crc-itu-t.h - CRC ITU-T V.41 routine
> + *
> + * Implements the standard CRC ITU-T V.41:
> + *   Width 16
> + *   Poly  0x0x1021 (x^16 + x^12 + x^15 + 1)

what does 0x0x.... mean?  and aren't poly exponents usually
listed in descending order?  or should the 15 be 5?

> + *   Init  0
> + *
> + * This source code is licensed under the GNU General Public License,
> + * Version 2. See the file COPYING for more details.
> + */

> diff --git a/lib/crc-itu-t.c b/lib/crc-itu-t.c
> new file mode 100644
> index 0000000..b4d4a21
> --- /dev/null
> +++ b/lib/crc-itu-t.c
> @@ -0,0 +1,68 @@
> +
> +/**
> + * Compute the CRC-ITU-T for the data buffer

Please use Linux kernel-doc format.  See
Documentation/kernel-doc-nano-HOWTO.txt.  Basically:

 * crc_itu_t - compute the CRC-ITU-T for the data buffer

and make parameter changes below:

> + *
> + * @param crc     previous CRC value
> + * @param buffer  data pointer
> + * @param len     number of bytes in the buffer

 * @crc:	previous CRC value
 * @buffer:	data pointer
 * @len:	number of bytes in the buffer
 *
 * Returns the updated CRC value.

> + * @return        the updated CRC value
> + */
> +u16 crc_itu_t(u16 crc, const u8 *buffer, size_t len)
> +{


---
~Randy