mbed-os/targets/TARGET_STM/lp_ticker.c

89 lines
2.7 KiB
C

/* mbed Microcontroller Library
*******************************************************************************
* Copyright (c) 2016, STMicroelectronics
* All rights reserved.
*
* 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 of STMicroelectronics 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 HOLDER 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.
*******************************************************************************
*/
#include "device.h"
#if DEVICE_LOWPOWERTIMER
#include "ticker_api.h"
#include "lp_ticker_api.h"
#include "rtc_api.h"
#include "rtc_api_hal.h"
static uint8_t lp_ticker_inited = 0;
void lp_ticker_init(void)
{
if (lp_ticker_inited) return;
lp_ticker_inited = 1;
rtc_init();
rtc_set_irq_handler((uint32_t) lp_ticker_irq_handler);
}
uint32_t lp_ticker_read(void)
{
uint32_t usecs = 0;
time_t time = 0;
lp_ticker_init();
do {
time = rtc_read();
usecs = rtc_read_subseconds();
} while (time != rtc_read());
return (time * 1000000) + usecs;
}
void lp_ticker_set_interrupt(timestamp_t timestamp)
{
uint32_t delta;
delta = timestamp - lp_ticker_read();
rtc_set_wake_up_timer(delta);
}
void lp_ticker_fire_interrupt(void)
{
NVIC_SetPendingIRQ(RTC_WKUP_IRQn);
}
void lp_ticker_disable_interrupt(void)
{
rtc_deactivate_wake_up_timer();
}
void lp_ticker_clear_interrupt(void)
{
}
#endif