/****************************************************************************
* drivers/1wire/1wire_internal.h
*
* Copyright (C) 2018 Haltian Ltd. All rights reserved.
* Author: Juha Niskanen <juha.niskanen@haltian.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
#ifndef __DRIVERS_1WIRE_1WIRE_INTERNAL_H
#define __DRIVERS_1WIRE_1WIRE_INTERNAL_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdbool.h>
#include <nuttx/semaphore.h>
#include <nuttx/power/pm.h>
/****************************************************************************
* Public Types
****************************************************************************/
struct onewire_dev_s;
struct onewire_sem_s
{
sem_t sem;
pid_t holder; /* The current holder of the semaphore */
int16_t count; /* Number of counts held */
};
struct onewire_master_s
{
FAR struct onewire_dev_s *dev; /* 1-Wire lower half */
struct onewire_sem_s devsem; /* Re-entrant semaphore */
int nslaves; /* Number of 1-wire slaves */
int maxslaves; /* Maximum number of 1-wire slaves */
bool insearch; /* If we are in middle of 1-wire search */
#ifdef CONFIG_PM
struct pm_callback_s pm_cb; /* PM callbacks */
#endif
};
struct onewire_slave_s
{
FAR struct onewire_master_s *master; /* Slave's bus master */
uint64_t romcode; /* Unique ROM id in bus */
};
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
/* CRC helpers from 1wire_crc.c */
uint8_t onewire_crc8(FAR const uint8_t *input, uint8_t len);
uint16_t onewire_crc16(FAR const uint8_t *input, uint16_t len,
uint16_t initial_crc);
bool onewire_valid_rom(uint64_t rom);
bool onewire_check_crc16(FAR const uint8_t *input, uint16_t len,
FAR const uint8_t *inverted_crc);
/* Rest are from 1wire.c */
int onewire_sem_wait(FAR struct onewire_master_s *master);
void onewire_sem_post(FAR struct onewire_master_s *master);
int onewire_addslave(FAR struct onewire_master_s *master,
FAR struct onewire_slave_s *slave);
int onewire_removeslave(FAR struct onewire_master_s *master,
FAR struct onewire_slave_s *slave);
/****************************************************************************
* Name: onewire_reset_resume
*
* Description:
*
****************************************************************************/
int onewire_reset_resume(FAR struct onewire_master_s *master);
/****************************************************************************
* Name: onewire_reset_select
*
* Description:
*
****************************************************************************/
int onewire_reset_select(FAR struct onewire_slave_s *slave);
/****************************************************************************
* Name: onewire_triplet
*
* Description:
* Used by 1-wire search algorithm. Reads two bits and writes
* one based on comparison of read bits.
*
* Input Parameters:
* search_bit - Bit to write if both id_bit and cmp_id_bit match
*
* Output Parameters:
* taken_bit - Bit indicating the direction where the search is
* progressing.
*
* Return Value:
* Number of valid bits or negative on error.
*
****************************************************************************/
int onewire_triplet(FAR struct onewire_master_s *master,
uint8_t search_bit,
FAR uint8_t *taken_bit);
/****************************************************************************
* Name: onewire_search
*
* Description:
* Search all devices from a 1-wire network. This is the 1-wire search
* algorithm from Maxim Application Note 187.
*
* Input Parameters:
* master - Pointer to the allocated 1-wire interface
* family - Limit search to devices of matching family
* alarmonly - Limit search to devices on alarm state
* cb_search - Callback to call on each device found
* arg - Argument passed to cb_search
*
* Return Value:
* Number of slaves present and matching family.
*
****************************************************************************/
int onewire_search(FAR struct onewire_master_s *master,
int family,
bool alarmonly,
CODE void (*cb_search)(int family,
uint64_t romcode,
FAR void *arg),
FAR void *arg);
/****************************************************************************
* Name: onewire_initialize
*
* Description:
* Return 1-wire bus master from 1-wire lower half device.
*
* Input Parameters:
* dev - Pointer to the allocated 1-wire lower half
* maxslaves - Maximum number of 1-wire slave devices
*
****************************************************************************/
FAR struct onewire_master_s *
onewire_initialize(FAR struct onewire_dev_s *dev, int maxslaves);
/****************************************************************************
* Name: onewire_uninitialize
*
* Description:
* Release 1-wire bus master.
*
* Input Parameters:
* master - Pointer to the allocated 1-wire master
*
****************************************************************************/
int onewire_uninitialize(FAR struct onewire_master_s *master);
#endif /* __DRIVERS_1WIRE_1WIRE_INTERNAL_H */