incubator-nuttx/drivers/1wire/1wire_internal.h

155 lines
5.5 KiB
C

/****************************************************************************
* drivers/1wire/1wire_internal.h
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
#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
****************************************************************************/
/* Additional CRC helpers from 1wire_crc.c */
bool onewire_valid_rom(uint64_t rom);
/* 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_master_s *master,
uint64_t romcode);
/****************************************************************************
* 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. Note! This is an atomic
* operation. The callback 'cb_search' can't execute any function that will
* lock this bus, because of the locked state as long the search is active.
*
* 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);
#endif /* __DRIVERS_1WIRE_1WIRE_INTERNAL_H */