owb.h

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/*
 * MIT License
 *
 * Copyright (c) 2017 David Antliff
 * Copyright (c) 2017 Chris Morgan <chmorgan@gmail.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
 
#ifndef ONE_WIRE_BUS_H
#define ONE_WIRE_BUS_H
 
#include <stdint.h>
#include <stdbool.h>
#include <stddef.h>
#include "driver/gpio.h"
 
#ifdef __cplusplus
extern "C" {
#endif
 
 
// ROM commands
#define OWB_ROM_SEARCH        0xF0  
#define OWB_ROM_READ          0x33  
#define OWB_ROM_MATCH         0x55  
#define OWB_ROM_SKIP          0xCC  
#define OWB_ROM_SEARCH_ALARM  0xEC  
 
#define OWB_ROM_CODE_STRING_LENGTH (17)  
 
#ifndef GPIO_NUM_NC
#  define GPIO_NUM_NC (-1)  
#endif
 
struct owb_driver;
 
typedef struct
{
    const struct _OneWireBus_Timing * timing;   
    bool use_crc;                               
    bool use_parasitic_power;                   
    gpio_num_t strong_pullup_gpio;              
    const struct owb_driver * driver;           
} OneWireBus;
 
typedef union
{
    struct fields
    {
        uint8_t family[1];         
        uint8_t serial_number[6];  
        uint8_t crc[1];            
    } fields;                      
 
    uint8_t bytes[8];              
 
} OneWireBus_ROMCode;
 
typedef struct
{
    OneWireBus_ROMCode rom_code;   
    int last_discrepancy;          
    int last_family_discrepancy;   
    int last_device_flag;          
} OneWireBus_SearchState;
 
typedef enum
{
    OWB_STATUS_NOT_SET = -1,           
    OWB_STATUS_OK = 0,                 
    OWB_STATUS_NOT_INITIALIZED,        
    OWB_STATUS_PARAMETER_NULL,         
    OWB_STATUS_DEVICE_NOT_RESPONDING,  
    OWB_STATUS_CRC_FAILED,             
    OWB_STATUS_TOO_MANY_BITS,          
    OWB_STATUS_HW_ERROR                
} owb_status;
 
struct owb_driver
{
    const char* name;
 
    owb_status (*uninitialize)(const OneWireBus * bus);
 
    owb_status (*reset)(const OneWireBus * bus, bool *is_present);
 
    owb_status (*write_bits)(const OneWireBus *bus, uint8_t out, int number_of_bits_to_write);
 
    owb_status (*read_bits)(const OneWireBus *bus, uint8_t *in, int number_of_bits_to_read);
};
 
#define container_of(ptr, type, member) ({                      \
        const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
        (type *)( (char *)__mptr - offsetof(type,member) );})
 
owb_status owb_uninitialize(OneWireBus * bus);
 
owb_status owb_use_crc(OneWireBus * bus, bool use_crc);
 
owb_status owb_use_parasitic_power(OneWireBus * bus, bool use_parasitic_power);
 
owb_status owb_use_strong_pullup_gpio(OneWireBus * bus, gpio_num_t gpio);
 
owb_status owb_read_rom(const OneWireBus * bus, OneWireBus_ROMCode * rom_code);
 
owb_status owb_verify_rom(const OneWireBus * bus, OneWireBus_ROMCode rom_code, bool * is_present);
 
owb_status owb_reset(const OneWireBus * bus, bool * is_present);
 
owb_status owb_read_bit(const OneWireBus * bus, uint8_t * out);
 
owb_status owb_read_byte(const OneWireBus * bus, uint8_t * out);
 
owb_status owb_read_bytes(const OneWireBus * bus, uint8_t * buffer, unsigned int len);
 
owb_status owb_write_bit(const OneWireBus * bus, uint8_t bit);
 
owb_status owb_write_byte(const OneWireBus * bus, uint8_t data);
 
owb_status owb_write_bytes(const OneWireBus * bus, const uint8_t * buffer, size_t len);
 
owb_status owb_write_rom_code(const OneWireBus * bus, OneWireBus_ROMCode rom_code);
 
uint8_t owb_crc8_byte(uint8_t crc, uint8_t data);
 
uint8_t owb_crc8_bytes(uint8_t crc, const uint8_t * data, size_t len);
 
owb_status owb_search_first(const OneWireBus * bus, OneWireBus_SearchState * state, bool *found_device);
 
owb_status owb_search_next(const OneWireBus * bus, OneWireBus_SearchState * state, bool *found_device);
 
char * owb_string_from_rom_code(OneWireBus_ROMCode rom_code, char * buffer, size_t len);
 
owb_status owb_set_strong_pullup(const OneWireBus * bus, bool enable);
 
 
#include "owb_gpio.h"
#include "owb_rmt.h"
 
#ifdef __cplusplus
}
#endif
 
#endif  // ONE_WIRE_BUS_H