rockbox/firmware/drivers/rtc/rtc_m41st84w.c
Daniel Stenberg 2acc0ac542 Updated our source code header to explicitly mention that we are GPL v2 or
later. We still need to hunt down snippets used that are not. 1324 modified
files...
http://www.rockbox.org/mail/archive/rockbox-dev-archive-2008-06/0060.shtml


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@17847 a1c6a512-1295-4272-9138-f99709370657
2008-06-28 18:10:04 +00:00

282 lines
6.9 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2002 by Linus Nielsen Feltzing, Uwe Freese, Laurent Baum
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* 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 <stdbool.h>
#define RTC_ADR 0xd0
#define RTC_DEV_WRITE (RTC_ADR | 0x00)
#define RTC_DEV_READ (RTC_ADR | 0x01)
void rtc_init(void)
{
unsigned char data;
#ifdef HAVE_RTC_ALARM
/* Check + save alarm bit first, before the power thread starts watching */
rtc_check_alarm_started(false);
#endif
rtc_write(0x13, 0x10); /* 32 kHz square wave */
/* Clear the Stop bit if it is set */
data = rtc_read(0x01);
if(data & 0x80)
rtc_write(0x01, 0x00);
/* Clear the HT bit if it is set */
data = rtc_read(0x0c);
if(data & 0x40)
{
data &= ~0x40;
rtc_write(0x0c,data);
}
#ifdef HAVE_RTC_ALARM
/* Clear Trec bit, write-protecting the RTC for 200ms when shutting off */
/* without this, the alarm won't work! */
data = rtc_read(0x04);
if (data & 0x80)
{
data &= ~0x80;
rtc_write(0x04, data);
}
/* Also, make sure that the OUT bit in register 8 is 1,
otherwise the player can't be turned off. */
rtc_write(8, rtc_read(8) | 0x80);
#endif
}
#ifdef HAVE_RTC_ALARM
/* check whether the unit has been started by the RTC alarm function */
/* (check for AF, 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 AL register. This call resets AL once read.
*
* We're only interested if ABE is set. AL is still raised regardless
* even if the unit is off when the alarm occurs.
*/
bool rtc_check_alarm_flag(void)
{
return ( ( (rtc_read(0x0f) & 0x40) != 0) &&
(rtc_read(0x0a) & 0x20) );
}
/* set alarm time registers to the given time (repeat once per day) */
void rtc_set_alarm(int h, int m)
{
unsigned char data;
/* for daily alarm, RPT5=RPT4=on, RPT1=RPT2=RPT3=off */
rtc_write(0x0e, 0x00); /* seconds 0 and RTP1 */
rtc_write(0x0d, ((m / 10) << 4) | (m % 10)); /* minutes and RPT2 */
rtc_write(0x0c, ((h / 10) << 4) | (h % 10)); /* hour and RPT3 */
rtc_write(0x0b, 0xc1); /* set date 01 and RPT4 and RTP5 */
/* set month to 1, if it's invalid, the rtc does an alarm every second instead */
data = rtc_read(0x0a);
data &= 0xe0;
data |= 0x01;
rtc_write(0x0a, data);
}
/* read out the current alarm time */
void rtc_get_alarm(int *h, int *m)
{
unsigned char data;
data = rtc_read(0x0c);
*h = ((data & 0x30) >> 4) * 10 + (data & 0x0f);
data = rtc_read(0x0d);
*m = ((data & 0x70) >> 4) * 10 + (data & 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 data = rtc_read(0x0a);
if (enable)
{
data |= 0xa0; /* turn bit d7=AFE and d5=ABE on */
}
else
data &= 0x5f; /* turn bit d7=AFE and d5=ABE off */
rtc_write(0x0a, data);
/* check if alarm flag AF is off (as it should be) */
/* in some cases enabling the alarm results in an activated AF flag */
/* this should not happen, but it does */
/* if you know why, tell me! */
/* for now, we try again forever in this case */
while (rtc_check_alarm_flag()) /* on */
{
data &= 0x5f; /* turn bit d7=AFE and d5=ABE off */
rtc_write(0x0a, data);
sleep(HZ / 10);
rtc_check_alarm_flag();
data |= 0xa0; /* turn bit d7=AFE and d5=ABE on */
rtc_write(0x0a, data);
}
return false; /* all ok */
}
#endif /* HAVE_RTC_ALARM */
int rtc_write(unsigned char address, unsigned char value)
{
int ret = 0;
unsigned char buf[2];
i2c_begin();
buf[0] = address;
buf[1] = value;
/* send run command */
if (i2c_write(RTC_DEV_WRITE,buf,2))
{
ret = -1;
}
i2c_end();
return ret;
}
int rtc_read(unsigned char address)
{
int value = -1;
unsigned char buf[1];
i2c_begin();
buf[0] = address;
/* send read command */
if (i2c_write(RTC_DEV_READ,buf,1) >= 0)
{
i2c_start();
i2c_outb(RTC_DEV_READ);
if (i2c_getack())
{
value = i2c_inb(1);
}
}
i2c_stop();
i2c_end();
return value;
}
int rtc_read_multiple(unsigned char address, unsigned char *buf, int numbytes)
{
int ret = 0;
unsigned char obuf[1];
int i;
i2c_begin();
obuf[0] = address;
/* send read command */
if (i2c_write(RTC_DEV_READ, obuf, 1) >= 0)
{
i2c_start();
i2c_outb(RTC_DEV_READ);
if (i2c_getack())
{
for(i = 0;i < numbytes-1;i++)
buf[i] = i2c_inb(0);
buf[i] = i2c_inb(1);
}
else
{
ret = -1;
}
}
i2c_stop();
i2c_end();
return ret;
}
int rtc_read_datetime(unsigned char* buf) {
int rc;
rc = rtc_read_multiple(1, buf, 7);
/* Adjust weekday */
if(buf[3] == 7)
buf[3]=0;
return rc;
}
int rtc_write_datetime(unsigned char* buf) {
int i;
int rc = 0;
/* Adjust weekday */
if(buf[3] == 0)
buf[3] = 7;
for (i = 0; i < 7 ; i++)
{
rc |= rtc_write(i+1, buf[i]);
}
rc |= rtc_write(8, 0x80); /* Out=1, calibration = 0 */
return rc;
}