soft_rtc.c

/*
 * File      : soft_rtc.c
 * This file is part of RT-Thread RTOS
 * COPYRIGHT (C) 2006 - 2018, RT-Thread Development Team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Change Logs:
 * Date           Author       Notes
 * 2018-01-30     armink       the first version
 */

#include <time.h>
#include <string.h>
#include <rtthread.h>

#include <drivers/rtc.h>

#ifdef RT_USING_SOFT_RTC

/* 2018-01-30 14:44:50 = RTC_TIME_INIT(2018, 1, 30, 14, 44, 50)  */
#define RTC_TIME_INIT(year, month, day, hour, minute, second)        \
    {.tm_year = year - 1900, .tm_mon = month - 1, .tm_mday = day, .tm_hour = hour, .tm_min = minute, .tm_sec = second}

#ifndef SOFT_RTC_TIME_DEFAULT
#define SOFT_RTC_TIME_DEFAULT                    RTC_TIME_INIT(2018, 1, 1, 0, 0 ,0)
#endif

static struct rt_device soft_rtc_dev;
static rt_tick_t init_tick;
static time_t init_time;

static rt_err_t soft_rtc_control(rt_device_t dev, int cmd, void *args)
{
    time_t *time;
    struct tm time_temp;

    RT_ASSERT(dev != RT_NULL);
    memset(&time_temp, 0, sizeof(struct tm));

    switch (cmd)
    {
    case RT_DEVICE_CTRL_RTC_GET_TIME:
        time = (time_t *) args;
        *time = init_time + (rt_tick_get() - init_tick) / RT_TICK_PER_SECOND;
        break;

    case RT_DEVICE_CTRL_RTC_SET_TIME:
    {
        time = (time_t *) args;
        init_time = *time - (rt_tick_get() - init_tick) / RT_TICK_PER_SECOND;
        break;
    }
    }

    return RT_EOK;
}

#ifdef RT_USING_DEVICE_OPS
const static struct rt_device_ops soft_rtc_ops = 
{
    RT_NULL,
    RT_NULL,
    RT_NULL,
    RT_NULL,
    RT_NULL,
    soft_rtc_control
};
#endif

int rt_soft_rtc_init(void)
{
    static rt_bool_t init_ok = RT_FALSE;
    struct tm time_new = SOFT_RTC_TIME_DEFAULT;

    if (init_ok)
    {
        return 0;
    }
    /* make sure only one 'rtc' device */
    RT_ASSERT(!rt_device_find("rtc"));

    init_tick = rt_tick_get();
    init_time = mktime(&time_new);

    soft_rtc_dev.type    = RT_Device_Class_RTC;

    /* register rtc device */
#ifdef RT_USING_DEVICE_OPS
    soft_rtc_dev.ops     = &soft_rtc_ops;
#else
    soft_rtc_dev.init    = RT_NULL;
    soft_rtc_dev.open    = RT_NULL;
    soft_rtc_dev.close   = RT_NULL;
    soft_rtc_dev.read    = RT_NULL;
    soft_rtc_dev.write   = RT_NULL;
    soft_rtc_dev.control = soft_rtc_control;
#endif

    /* no private */
    soft_rtc_dev.user_data = RT_NULL;

    rt_device_register(&soft_rtc_dev, "rtc", RT_DEVICE_FLAG_RDWR);

    init_ok = RT_TRUE;

    return 0;
}
INIT_DEVICE_EXPORT(rt_soft_rtc_init);

#endif /* RT_USING_SOFT_RTC */