From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-bw0-f49.google.com ([209.85.214.49]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1RTK7M-0004Ya-Ml for barebox@lists.infradead.org; Wed, 23 Nov 2011 21:12:33 +0000 Received: by bkat2 with SMTP id t2so2163873bka.36 for ; Wed, 23 Nov 2011 13:12:30 -0800 (PST) From: franck.jullien@gmail.com Date: Wed, 23 Nov 2011 22:12:25 +0100 Message-Id: <1322082748-17409-2-git-send-email-franck.jullien@gmail.com> In-Reply-To: <1322082748-17409-1-git-send-email-franck.jullien@gmail.com> References: <1322082748-17409-1-git-send-email-franck.jullien@gmail.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: barebox-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH 1/4] crypto: Add crc7 function To: barebox@lists.infradead.org From: Franck Jullien This function in used by the MCI over SPI driver. Signed-off-by: Franck Jullien --- crypto/Kconfig | 3 ++ crypto/Makefile | 1 + crypto/crc7.c | 63 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ include/crc7.h | 14 ++++++++++++ 4 files changed, 81 insertions(+), 0 deletions(-) create mode 100644 crypto/crc7.c create mode 100644 include/crc7.h diff --git a/crypto/Kconfig b/crypto/Kconfig index a391ae6..a6fc1b8 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -4,6 +4,9 @@ config CRC32 config CRC16 bool +config CRC7 + bool + menuconfig DIGEST bool "Digest " diff --git a/crypto/Makefile b/crypto/Makefile index 955a66d..7c5b035 100644 --- a/crypto/Makefile +++ b/crypto/Makefile @@ -1,5 +1,6 @@ obj-$(CONFIG_CRC32) += crc32.o obj-$(CONFIG_CRC16) += crc16.o +obj-$(CONFIG_CRC7) += crc7.o obj-$(CONFIG_MD5) += md5.o obj-$(CONFIG_SHA1) += sha1.o obj-$(CONFIG_SHA224) += sha2.o diff --git a/crypto/crc7.c b/crypto/crc7.c new file mode 100644 index 0000000..8022199 --- /dev/null +++ b/crypto/crc7.c @@ -0,0 +1,63 @@ +/* + * crc7.c + * + * This source code is licensed under the GNU General Public License, + * Version 2. See the file COPYING for more details. + */ + +#include +#include + + +/* Table for CRC-7 (polynomial x^7 + x^3 + 1) */ +const u8 crc7_syndrome_table[256] = { + 0x00, 0x09, 0x12, 0x1b, 0x24, 0x2d, 0x36, 0x3f, + 0x48, 0x41, 0x5a, 0x53, 0x6c, 0x65, 0x7e, 0x77, + 0x19, 0x10, 0x0b, 0x02, 0x3d, 0x34, 0x2f, 0x26, + 0x51, 0x58, 0x43, 0x4a, 0x75, 0x7c, 0x67, 0x6e, + 0x32, 0x3b, 0x20, 0x29, 0x16, 0x1f, 0x04, 0x0d, + 0x7a, 0x73, 0x68, 0x61, 0x5e, 0x57, 0x4c, 0x45, + 0x2b, 0x22, 0x39, 0x30, 0x0f, 0x06, 0x1d, 0x14, + 0x63, 0x6a, 0x71, 0x78, 0x47, 0x4e, 0x55, 0x5c, + 0x64, 0x6d, 0x76, 0x7f, 0x40, 0x49, 0x52, 0x5b, + 0x2c, 0x25, 0x3e, 0x37, 0x08, 0x01, 0x1a, 0x13, + 0x7d, 0x74, 0x6f, 0x66, 0x59, 0x50, 0x4b, 0x42, + 0x35, 0x3c, 0x27, 0x2e, 0x11, 0x18, 0x03, 0x0a, + 0x56, 0x5f, 0x44, 0x4d, 0x72, 0x7b, 0x60, 0x69, + 0x1e, 0x17, 0x0c, 0x05, 0x3a, 0x33, 0x28, 0x21, + 0x4f, 0x46, 0x5d, 0x54, 0x6b, 0x62, 0x79, 0x70, + 0x07, 0x0e, 0x15, 0x1c, 0x23, 0x2a, 0x31, 0x38, + 0x41, 0x48, 0x53, 0x5a, 0x65, 0x6c, 0x77, 0x7e, + 0x09, 0x00, 0x1b, 0x12, 0x2d, 0x24, 0x3f, 0x36, + 0x58, 0x51, 0x4a, 0x43, 0x7c, 0x75, 0x6e, 0x67, + 0x10, 0x19, 0x02, 0x0b, 0x34, 0x3d, 0x26, 0x2f, + 0x73, 0x7a, 0x61, 0x68, 0x57, 0x5e, 0x45, 0x4c, + 0x3b, 0x32, 0x29, 0x20, 0x1f, 0x16, 0x0d, 0x04, + 0x6a, 0x63, 0x78, 0x71, 0x4e, 0x47, 0x5c, 0x55, + 0x22, 0x2b, 0x30, 0x39, 0x06, 0x0f, 0x14, 0x1d, + 0x25, 0x2c, 0x37, 0x3e, 0x01, 0x08, 0x13, 0x1a, + 0x6d, 0x64, 0x7f, 0x76, 0x49, 0x40, 0x5b, 0x52, + 0x3c, 0x35, 0x2e, 0x27, 0x18, 0x11, 0x0a, 0x03, + 0x74, 0x7d, 0x66, 0x6f, 0x50, 0x59, 0x42, 0x4b, + 0x17, 0x1e, 0x05, 0x0c, 0x33, 0x3a, 0x21, 0x28, + 0x5f, 0x56, 0x4d, 0x44, 0x7b, 0x72, 0x69, 0x60, + 0x0e, 0x07, 0x1c, 0x15, 0x2a, 0x23, 0x38, 0x31, + 0x46, 0x4f, 0x54, 0x5d, 0x62, 0x6b, 0x70, 0x79 +}; + +/** + * crc7 - update the CRC7 for the data buffer + * @crc: previous CRC7 value + * @buffer: data pointer + * @len: number of bytes in the buffer + * Context: any + * + * Returns the updated CRC7 value. + */ +u8 crc7(u8 crc, const u8 *buffer, size_t len) +{ + while (len--) + crc = crc7_byte(crc, *buffer++); + return crc; +} +EXPORT_SYMBOL(crc7); diff --git a/include/crc7.h b/include/crc7.h new file mode 100644 index 0000000..0c41cc3 --- /dev/null +++ b/include/crc7.h @@ -0,0 +1,14 @@ +#ifndef _LINUX_CRC7_H +#define _LINUX_CRC7_H +#include + +extern const u8 crc7_syndrome_table[256]; + +static inline u8 crc7_byte(u8 crc, u8 data) +{ + return crc7_syndrome_table[(crc << 1) ^ data]; +} + +extern u8 crc7(u8 crc, const u8 *buffer, size_t len); + +#endif -- 1.7.7 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox