u-boot/include/rtc.h
Simon Glass 9f9276c34c dm: rtc: Rename to_tm() to rtc_to_tm() and add error code
Rename this function so that it is clear that it is provided by the RTC.
Also return an error when it cannot function as expected. This is unlikely
to occur since it works for dates since 1752 and many RTCs do not support
such old dates. Still it is better to be accurate.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Heiko Schocher <hs@denx.de>
2015-05-05 20:58:20 -06:00

113 lines
2.5 KiB
C

/*
* (C) Copyright 2001
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* SPDX-License-Identifier: GPL-2.0+
*/
/*
* Generic RTC interface.
*/
#ifndef _RTC_H_
#define _RTC_H_
/* bcd<->bin functions are needed by almost all the RTC drivers, let's include
* it there instead of in evey single driver */
#include <bcd.h>
/*
* The struct used to pass data from the generic interface code to
* the hardware dependend low-level code ande vice versa. Identical
* to struct rtc_time used by the Linux kernel.
*
* Note that there are small but significant differences to the
* common "struct time":
*
* struct time: struct rtc_time:
* tm_mon 0 ... 11 1 ... 12
* tm_year years since 1900 years since 0
*/
struct rtc_time {
int tm_sec;
int tm_min;
int tm_hour;
int tm_mday;
int tm_mon;
int tm_year;
int tm_wday;
int tm_yday;
int tm_isdst;
};
int rtc_get (struct rtc_time *);
int rtc_set (struct rtc_time *);
void rtc_reset (void);
unsigned long mktime (unsigned int, unsigned int, unsigned int,
unsigned int, unsigned int, unsigned int);
/**
* rtc_read8() - Read an 8-bit register
*
* @reg: Register to read
* @return value read
*/
int rtc_read8(int reg);
/**
* rtc_write8() - Write an 8-bit register
*
* @reg: Register to write
* @value: Value to write
*/
void rtc_write8(int reg, uchar val);
/**
* rtc_read32() - Read a 32-bit value from the RTC
*
* @reg: Offset to start reading from
* @return value read
*/
u32 rtc_read32(int reg);
/**
* rtc_write32() - Write a 32-bit value to the RTC
*
* @reg: Register to start writing to
* @value: Value to write
*/
void rtc_write32(int reg, u32 value);
/**
* rtc_init() - Set up the real time clock ready for use
*/
void rtc_init(void);
/**
* rtc_calc_weekday() - Work out the weekday from a time
*
* This only works for the Gregorian calendar - i.e. after 1752 (in the UK).
* It sets time->tm_wdaay to the correct day of the week.
*
* @time: Time to inspect. tm_wday is updated
* @return 0 if OK, -EINVAL if the weekday could not be determined
*/
int rtc_calc_weekday(struct rtc_time *time);
/**
* rtc_to_tm() - Convert a time_t value into a broken-out time
*
* The following fields are set up by this function:
* tm_sec, tm_min, tm_hour, tm_mday, tm_mon, tm_year, tm_wday
*
* Note that tm_yday and tm_isdst are set to 0.
*
* @time_t: Number of seconds since 1970-01-01 00:00:00
* @time: Place to put the broken-out time
* @return 0 if OK, -EINVAL if the weekday could not be determined
*/
int rtc_to_tm(int time_t, struct rtc_time *time);
#endif /* _RTC_H_ */