| 1 | |
| 2 | * crc7.c
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| 3 | *
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| 4 | * This source code is licensed under the GNU General Public License,
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| 5 | * Version 2. See the file COPYING for more details.
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| 6 |
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| 7 |
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| 8 | #include <linux/types.h>
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| 9 | #include <linux/module.h>
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| 10 | #include <linux/crc7.h>
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| 11 |
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| 12 |
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| 13 |
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| 14 | const u8 crc7_syndrome_table[256] = {
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| 15 | 0x00, 0x09, 0x12, 0x1b, 0x24, 0x2d, 0x36, 0x3f,
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| 16 | 0x48, 0x41, 0x5a, 0x53, 0x6c, 0x65, 0x7e, 0x77,
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| 17 | 0x19, 0x10, 0x0b, 0x02, 0x3d, 0x34, 0x2f, 0x26,
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| 18 | 0x51, 0x58, 0x43, 0x4a, 0x75, 0x7c, 0x67, 0x6e,
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| 19 | 0x32, 0x3b, 0x20, 0x29, 0x16, 0x1f, 0x04, 0x0d,
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| 20 | 0x7a, 0x73, 0x68, 0x61, 0x5e, 0x57, 0x4c, 0x45,
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| 21 | 0x2b, 0x22, 0x39, 0x30, 0x0f, 0x06, 0x1d, 0x14,
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| 22 | 0x63, 0x6a, 0x71, 0x78, 0x47, 0x4e, 0x55, 0x5c,
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| 23 | 0x64, 0x6d, 0x76, 0x7f, 0x40, 0x49, 0x52, 0x5b,
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| 24 | 0x2c, 0x25, 0x3e, 0x37, 0x08, 0x01, 0x1a, 0x13,
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| 25 | 0x7d, 0x74, 0x6f, 0x66, 0x59, 0x50, 0x4b, 0x42,
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| 26 | 0x35, 0x3c, 0x27, 0x2e, 0x11, 0x18, 0x03, 0x0a,
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| 27 | 0x56, 0x5f, 0x44, 0x4d, 0x72, 0x7b, 0x60, 0x69,
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| 28 | 0x1e, 0x17, 0x0c, 0x05, 0x3a, 0x33, 0x28, 0x21,
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| 29 | 0x4f, 0x46, 0x5d, 0x54, 0x6b, 0x62, 0x79, 0x70,
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| 30 | 0x07, 0x0e, 0x15, 0x1c, 0x23, 0x2a, 0x31, 0x38,
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| 31 | 0x41, 0x48, 0x53, 0x5a, 0x65, 0x6c, 0x77, 0x7e,
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| 32 | 0x09, 0x00, 0x1b, 0x12, 0x2d, 0x24, 0x3f, 0x36,
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| 33 | 0x58, 0x51, 0x4a, 0x43, 0x7c, 0x75, 0x6e, 0x67,
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| 34 | 0x10, 0x19, 0x02, 0x0b, 0x34, 0x3d, 0x26, 0x2f,
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| 35 | 0x73, 0x7a, 0x61, 0x68, 0x57, 0x5e, 0x45, 0x4c,
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| 36 | 0x3b, 0x32, 0x29, 0x20, 0x1f, 0x16, 0x0d, 0x04,
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| 37 | 0x6a, 0x63, 0x78, 0x71, 0x4e, 0x47, 0x5c, 0x55,
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| 38 | 0x22, 0x2b, 0x30, 0x39, 0x06, 0x0f, 0x14, 0x1d,
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| 39 | 0x25, 0x2c, 0x37, 0x3e, 0x01, 0x08, 0x13, 0x1a,
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| 40 | 0x6d, 0x64, 0x7f, 0x76, 0x49, 0x40, 0x5b, 0x52,
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| 41 | 0x3c, 0x35, 0x2e, 0x27, 0x18, 0x11, 0x0a, 0x03,
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| 42 | 0x74, 0x7d, 0x66, 0x6f, 0x50, 0x59, 0x42, 0x4b,
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| 43 | 0x17, 0x1e, 0x05, 0x0c, 0x33, 0x3a, 0x21, 0x28,
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| 44 | 0x5f, 0x56, 0x4d, 0x44, 0x7b, 0x72, 0x69, 0x60,
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| 45 | 0x0e, 0x07, 0x1c, 0x15, 0x2a, 0x23, 0x38, 0x31,
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| 46 | 0x46, 0x4f, 0x54, 0x5d, 0x62, 0x6b, 0x70, 0x79
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| 47 | };
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| 48 | EXPORT_SYMBOL(crc7_syndrome_table);
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| 49 |
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| 50 | |
| 51 | * crc7 - update the CRC7 for the data buffer
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| 52 | * @crc: previous CRC7 value
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| 53 | * @buffer: data pointer
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| 54 | * @len: number of bytes in the buffer
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| 55 | * Context: any
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| 56 | *
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| 57 | * Returns the updated CRC7 value.
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| 58 |
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| 59 | u8 crc7(u8 crc, const u8 *buffer, size_t len)
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| 60 | {
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| 61 | while (len--)
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| 62 | crc = crc7_byte(crc, *buffer++);
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| 63 | return crc;
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| 64 | }
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| 65 | EXPORT_SYMBOL(crc7);
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| 66 |
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| 67 | MODULE_DESCRIPTION("CRC7 calculations");
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| 68 | MODULE_LICENSE("GPL");
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