rockbox/firmware/drivers/rtc/rtc_pcf50605.c
Thom Johansen 1ef5dadec5 Try to fix the case where Ipods would spuriously wake up even though no alarm had been set.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@14885 a1c6a512-1295-4272-9138-f99709370657
2007-09-28 15:09:54 +00:00

135 lines
4.1 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2002 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 "config.h"
#include "i2c.h"
#include "rtc.h"
#include "kernel.h"
#include "system.h"
#include "pcf50605.h"
#include <stdbool.h>
/* Values which each disable one alarm time register */
static const char alarm_disable[] = {
0x7f, 0x7f, 0x3f, 0x07, 0x3f, 0x1f, 0xff
};
void rtc_init(void)
{
rtc_check_alarm_started(false);
}
int rtc_read_datetime(unsigned char* buf)
{
return pcf50605_read_multiple(0x0a, buf, 7);
}
int rtc_write_datetime(unsigned char* buf)
{
pcf50605_write_multiple(0x0a, buf, 7);
return 1;
}
/**
* Checks the PCF interrupt 1 register bit 7 to see if an alarm interrupt has
* triggered since last we checked.
*/
bool rtc_check_alarm_flag(void)
{
return pcf50605_read(0x02) & 0x80;
}
/**
* Enables or disables the alarm.
* The Ipod bootloader clears all PCF interrupt registers and always enables
* the "wake on RTC" bit on OOCC1, so we have to rely on other means to find
* out if we just woke from an alarm.
* Return value is always false for us.
*/
bool rtc_enable_alarm(bool enable)
{
if (enable) {
/* Tell the PCF to ignore everything but second, minute and hour, so
* that an alarm will trigger the next time the alarm time occurs.
*/
pcf50605_write_multiple(0x14, alarm_disable + 3, 4);
/* Unmask the alarm interrupt (might be unneeded) */
pcf50605_write(0x5, pcf50605_read(0x5) & ~0x80);
/* Make sure wake on RTC is set when shutting down */
pcf50605_wakeup_flags |= 0x10;
} else {
/* We use this year to indicate a disabled alarm. If you happen to live
* around this time and are annoyed by this, feel free to seek out my
* grave and do something nasty to it.
*/
pcf50605_write(0x17, 0x99);
/* Make sure we don't wake on RTC after shutting down */
pcf50605_wakeup_flags &= ~0x10;
}
return false;
}
/**
* Check if alarm caused unit to start.
*/
bool rtc_check_alarm_started(bool release_alarm)
{
static bool run_before = false, alarm_state;
bool rc;
if (run_before) {
rc = alarm_state;
alarm_state &= ~release_alarm;
} else {
char rt[3], at[3];
/* The Ipod bootloader seems to read (and thus clear) the PCF interrupt
* registers, so we need to find some other way to detect if an alarm
* just happened
*/
pcf50605_read_multiple(0x0a, rt, 3);
pcf50605_read_multiple(0x11, at, 3);
/* If alarm time and real time match within 10 seconds of each other, we
* assume an alarm just triggered
*/
rc = alarm_state = rt[1] == at[1] && rt[2] == at[2]
&& (rt[0] - at[0]) <= 10;
run_before = true;
}
return rc;
}
void rtc_set_alarm(int h, int m)
{
/* Set us to wake at the first second of the specified time */
pcf50605_write(0x11, 0);
/* Convert to BCD */
pcf50605_write(0x12, ((m/10) << 4) | m%10);
pcf50605_write(0x13, ((h/10) << 4) | h%10);
}
void rtc_get_alarm(int *h, int *m)
{
char buf[2];
pcf50605_read_multiple(0x12, buf, 2);
/* Convert from BCD */
*m = ((buf[0] >> 4) & 0x7)*10 + (buf[0] & 0x0f);
*h = ((buf[1] >> 4) & 0x3)*10 + (buf[1] & 0x0f);
}