rockbox/firmware/drivers/rtc/rtc_ds1339_ds3231.c
Robert Kukla 50b5ee4781 FS#6419 - driver for H1x0 series RTC Mod with runtime detection
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@12520 a1c6a512-1295-4272-9138-f99709370657
2007-02-28 13:20:36 +00:00

144 lines
3.9 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2006 by Robert Kukla
* based on Archos code by Linus Nielsen Feltzing, Uwe Freese, Laurent Baum
* All files in this archive are subject to the GNU General Public License.
* See the file COPYING in the source tree root for full license agreement.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "rtc.h"
#include "logf.h"
#include "sw_i2c.h"
#define RTC_ADDR 0xD0
bool rtc_detected = false;
void rtc_init(void)
{
char byte;
sw_i2c_init();
/* read one byte from RTC; 0 on success */
rtc_detected = !sw_i2c_read(RTC_ADDR, 0, &byte, 1);
#ifdef HAVE_ALARM_MOD
/* Check + save alarm bit first, before the power thread starts watching */
rtc_check_alarm_started(false);
#endif
}
#ifdef HAVE_ALARM_MOD
/* check whether the unit has been started by the RTC alarm function */
/* (check for A2F, which => started using wakeup alarm) */
bool rtc_check_alarm_started(bool release_alarm)
{
static bool alarm_state, run_before;
bool rc;
if (run_before) {
rc = alarm_state;
alarm_state &= ~release_alarm;
} else {
/* This call resets AF, so we store the state for later recall */
rc = alarm_state = rtc_check_alarm_flag();
run_before = true;
}
return rc;
}
/*
* Checks the A2F flag. This call resets A2F once read.
*
*/
bool rtc_check_alarm_flag(void)
{
unsigned char buf[1];
bool flag = false;
sw_i2c_read(RTC_ADDR, 0x0f, buf, 1);
if (buf[0] & 0x02) flag = true;
rtc_enable_alarm(false);
return flag;
}
/* set alarm time registers to the given time (repeat once per day) */
void rtc_set_alarm(int h, int m)
{
unsigned char buf[3];
buf[0] = (((m / 10) << 4) | (m % 10)) & 0x7f; /* minutes */
buf[1] = (((h / 10) << 4) | (h % 10)) & 0x3f; /* hour */
buf[2] = 0x80; /* repeat every day */
sw_i2c_write(RTC_ADDR, 0x0b, buf, 3);
}
/* read out the current alarm time */
void rtc_get_alarm(int *h, int *m)
{
unsigned char buf[2];
sw_i2c_read(RTC_ADDR, 0x0b, buf, 2);
*m = ((buf[0] & 0x70) >> 4) * 10 + (buf[0] & 0x0f);
*h = ((buf[1] & 0x30) >> 4) * 10 + (buf[1] & 0x0f);
}
/* turn alarm on or off by setting the alarm flag enable */
/* the alarm is automatically disabled when the RTC gets Vcc power at startup */
/* avoid that an alarm occurs when the device is on because this locks the ON key forever */
/* returns false if alarm was set and alarm flag (output) is off */
/* returns true if alarm flag went on, which would lock the device, so the alarm was disabled again */
bool rtc_enable_alarm(bool enable)
{
unsigned char buf[2];
buf[0] = enable ? 0x26 : 0x04; /* BBSQI INTCN A2IE vs INTCH only */
buf[1] = 0x00; /* reset alarm flags (and OSF for good measure) */
sw_i2c_write(RTC_ADDR, 0x0e, buf, 2);
return false; /* all ok */
}
#endif /* HAVE_ALARM_MOD */
int rtc_read_datetime(unsigned char* buf)
{
int i;
i = sw_i2c_read(RTC_ADDR, 0, buf, 7);
buf[3]--; /* timefuncs wants 0..6 for wday */
return i;
}
int rtc_write_datetime(unsigned char* buf)
{
int i;
buf[3]++; /* chip wants 1..7 for wday */
buf[5]|=0x80; /* chip wants century (always 20xx) */
i = sw_i2c_write(RTC_ADDR, 0, buf, 7);
return i;
}