* Intended usage is data validation in split transport code.
* Default space efficient algorithm.
* Opt-in fast table based algorithmn with #define CRC8_USE_TABLE switch.
* Define switches for size and speed optimized versions, the default is size
  optimized by using uint_least8_t as datatype for calculations.
  * #define CRC8_OPTIMIZE_SPEED uses uint_fast8_t as datatype for
    calculations, this only affects 32-bit Archs like ARM and RISC-V.
* Placeholder crc_init() function for hardware backed crc calculation,
  not implemented yet.
		
	
		
			
				
	
	
		
			44 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			44 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* Copyright 2021 QMK
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 *
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 * This program is free software: you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License as published by
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 * the Free Software Foundation, either version 2 of the License, or
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 * (at your option) any later version.
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 *
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 * This program is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 * GNU General Public License for more details.
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 *
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 * You should have received a copy of the GNU General Public License
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 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
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 */
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#pragma once
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#include "quantum.h"
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/**
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 * The type of the CRC values.
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 *
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 * This type must be big enough to contain at least 8 bits.
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 */
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#if defined(CRC8_OPTIMIZE_SPEED)
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typedef uint_fast8_t crc_t;
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#else
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typedef uint_least8_t crc_t;
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#endif
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/**
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 * Initialize crc subsystem.
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 */
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__attribute__((weak)) void crc_init(void);
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/**
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 * Generate CRC8 value from given data.
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 *
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 * \param[in] data     Pointer to a buffer of \a data_len bytes.
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 * \param[in] data_len Number of bytes in the \a data buffer.
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 * \return             The calculated crc value.
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 */
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__attribute__((weak)) uint8_t crc8(const void *data, size_t data_len); |