incubator-nuttx/include/nuttx/rtc.h

284 lines
10 KiB
C

/****************************************************************************
* include/nuttx/rtc.h
*
* Copyright(C) 2011 Uros Platise. All rights reserved.
* Author: Uros Platise <uros.platise@isotel.eu>
*
* With extensions, modifications by:
*
* Copyright (C) 2011-2012 Gregory Nutt. All rights reserved.
* Author: Gregroy Nutt <gnutt@nuttx.org>
*
* 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 __INCLUDE_NUTTX_RTC_H
#define __INCLUDE_NUTTX_RTC_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <stdbool.h>
#include <time.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
/* CONFIG_RTC - Enables general support for a hardware RTC. Specific
* architectures may require other specific settings.
*
* CONFIG_RTC_DATETIME - There are two general types of RTC: (1) A simple
* battery backed counter that keeps the time when power is down, and (2)
* A full date / time RTC the provides the date and time information, often
* in BCD format. If CONFIG_RTC_DATETIME is selected, it specifies this
* second kind of RTC. In this case, the RTC is used to "seed" the normal
* NuttX timer and the NuttX system timer provides for higher resoution
* time.
*
* CONFIG_RTC_HIRES - If CONFIG_RTC_DATETIME not selected, then the simple,
* battery backed counter is used. There are two different implementations
* of such simple counters based on the time resolution of the counter:
* The typical RTC keeps time to resolution of 1 second, usually
* supporting a 32-bit time_t value. In this case, the RTC is used to
* "seed" the normal NuttX timer and the NuttX timer provides for higher
* resoution time.
*
* If CONFIG_RTC_HIRES is enabled in the NuttX configuration, then the
* RTC provides higher resolution time and completely replaces the system
* timer for purpose of date and time.
*
* CONFIG_RTC_FREQUENCY - If CONFIG_RTC_HIRES is defined, then the frequency
* of the high resolution RTC must be provided. If CONFIG_RTC_HIRES is
* not defined, CONFIG_RTC_FREQUENCY is assumed to be one.
*
* CONFIG_RTC_ALARM - Enable if the RTC hardware supports setting of an
* alarm. A callback function will be executed when the alarm goes off
*/
#ifdef CONFIG_RTC_HIRES
# ifdef CONFIG_RTC_DATETIME
# error "CONFIG_RTC_HIRES and CONFIG_RTC_DATETIME are both defined"
# endif
# ifndef CONFIG_RTC_FREQUENCY
# error "CONFIG_RTC_FREQUENCY is required for CONFIG_RTC_HIRES"
# endif
#else
# ifndef CONFIG_RTC_FREQUENCY
# define CONFIG_RTC_FREQUENCY 1
# endif
# if CONFIG_RTC_FREQUENCY != 1
# error "The low resolution RTC must have frequency 1Hz"
# endif
#endif
/****************************************************************************
* Public Types
****************************************************************************/
/* The form of an alarm callback */
typedef CODE void (*alarmcb_t)(void);
/****************************************************************************
* Public Variables
****************************************************************************/
/* Variable determines the state of the RTC module.
*
* After initialization value is set to 'true' if RTC starts successfully.
* The value can be changed to false also during operation if RTC for
* some reason fails.
*/
extern volatile bool g_rtc_enabled;
/****************************************************************************
* Public Functions
****************************************************************************/
#undef EXTERN
#if defined(__cplusplus)
#define EXTERN extern "C"
extern "C" {
#else
#define EXTERN extern
#endif
/************************************************************************************
* Name: up_rtcinitialize
*
* Description:
* Initialize the hardware RTC per the selected configuration. This function is
* called once during the OS initialization sequence
*
* Input Parameters:
* None
*
* Returned Value:
* Zero (OK) on success; a negated errno on failure
*
************************************************************************************/
EXTERN int up_rtcinitialize(void);
/************************************************************************************
* Name: up_rtc_time
*
* Description:
* Get the current time in seconds. This is similar to the standard time()
* function. This interface is only required if the low-resolution RTC/counter
* hardware implementation selected. It is only used by the RTOS during
* intialization to set up the system time when CONFIG_RTC is set but neither
* CONFIG_RTC_HIRES nor CONFIG_RTC_DATETIME are set.
*
* Input Parameters:
* None
*
* Returned Value:
* The current time in seconds
*
************************************************************************************/
#ifndef CONFIG_RTC_HIRES
EXTERN time_t up_rtc_time(void);
#endif
/************************************************************************************
* Name: up_rtc_gettime
*
* Description:
* Get the current time from the high resolution RTC clock/counter. This interface
* is only supported by the high-resolution RTC/counter hardware implementation.
* It is used to replace the system timer.
*
* Input Parameters:
* tp - The location to return the high resolution time value.
*
* Returned Value:
* Zero (OK) on success; a negated errno on failure
*
************************************************************************************/
#ifdef CONFIG_RTC_HIRES
EXTERN int up_rtc_gettime(FAR struct timespec *tp);
#endif
/************************************************************************************
* Name: up_rtc_getdatetime
*
* Description:
* Get the current date and time from the date/time RTC. This interface
* is only supported by the date/time RTC hardware implementation.
* It is used to replace the system timer. It is only used by the RTOS during
* intialization to set up the system time when CONFIG_RTC and CONFIG_RTC_DATETIME
* are selected (and CONFIG_RTC_HIRES is not).
*
* NOTE: Some date/time RTC hardware is capability of sub-second accuracy. That
* sub-second accuracy is lost in this interface. However, since the system time
* is reinitialized on each power-up/reset, there will be no timing inaccuracy in
* the long run.
*
* Input Parameters:
* tp - The location to return the high resolution time value.
*
* Returned Value:
* Zero (OK) on success; a negated errno on failure
*
************************************************************************************/
#ifdef CONFIG_RTC_DATETIME
EXTERN int up_rtc_getdatetime(FAR struct tm *tp);
#endif
/************************************************************************************
* Name: up_rtc_settime
*
* Description:
* Set the RTC to the provided time. All RTC implementations must be able to
* set their time based on a standard timespec.
*
* Input Parameters:
* tp - the time to use
*
* Returned Value:
* Zero (OK) on success; a negated errno on failure
*
************************************************************************************/
EXTERN int up_rtc_settime(FAR const struct timespec *tp);
/************************************************************************************
* Name: up_rtc_setalarm
*
* Description:
* Set up an alarm.
*
* Input Parameters:
* tp - the time to set the alarm
* callback - the function to call when the alarm expires.
*
* Returned Value:
* Zero (OK) on success; a negated errno on failure
*
************************************************************************************/
#ifdef CONFIG_RTC_ALARM
EXTERN int up_rtc_setalarm(FAR const struct timespec *tp, alarmcb_t callback);
#endif
/************************************************************************************
* Name: up_rtc_cancelalarm
*
* Description:
* Cancel a pending alarm alarm
*
* Input Parameters:
* none
*
* Returned Value:
* Zero (OK) on success; a negated errno on failure
*
************************************************************************************/
#ifdef CONFIG_RTC_ALARM
EXTERN int up_rtc_cancelalarm(void);
#endif
#undef EXTERN
#if defined(__cplusplus)
}
#endif
#endif /* __INCLUDE_NUTTX_RTC_H */