summaryrefslogtreecommitdiffstats
path: root/firmware/drivers/rtc/rtc_pcf50606.c
blob: 8f5371635c8eed87e6987868e228928396ad313c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
/***************************************************************************
 *             __________               __   ___.
 *   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 "pcf50606.h"
#include "timefuncs.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(struct tm *tm)
{
    unsigned int i;
    int rc, oldlevel;
    unsigned char buf[7];

    oldlevel = disable_irq_save();

    rc = pcf50606_read_multiple(0x0a, buf, sizeof(buf));

    restore_irq(oldlevel);

    for (i = 0; i < sizeof(buf); i++)
        buf[i] = BCD2DEC(buf[i]);

    tm->tm_sec = buf[0];
    tm->tm_min = buf[1];
    tm->tm_hour = buf[2];
    tm->tm_mday = buf[4];
    tm->tm_mon = buf[5] - 1;

#ifdef IRIVER_H300_SERIES
    /* Special kludge to coexist with the iriver firmware. The iriver firmware
       stores the date as 1965+nn, and allows a range of 1980..2064. We use
       1964+nn here to make leap years work correctly, so the date will be one
       year off in the iriver firmware but at least won't be reset anymore. */
    tm->tm_year = buf[6] + 64;
#else /* Not IRIVER_H300_SERIES */
    tm->tm_year = buf[6] + 100;
#endif /* IRIVER_H300_SERIES */

    set_day_of_week(tm);
    set_day_of_year(tm);

    return rc;
}

int rtc_write_datetime(const struct tm *tm)
{
    unsigned int i;
    int rc, oldlevel;
    unsigned char buf[7];

    buf[0] = tm->tm_sec;
    buf[1] = tm->tm_min;
    buf[2] = tm->tm_hour;
    buf[3] = tm->tm_wday;
    buf[4] = tm->tm_mday;
    buf[5] = tm->tm_mon + 1;
#ifdef IRIVER_H300_SERIES
    /* Iriver firmware compatibility kludge, see rtc_read_datetime(). */
    buf[6] = tm->tm_year - 64;
#else /* Not IRIVER_H300_SERIES */
    buf[6] = tm->tm_year - 100;
#endif /* IRIVER_H300_SERIES */

    for (i = 0; i < sizeof(buf); i++)
         buf[i] = DEC2BCD(buf[i]);

    oldlevel = disable_irq_save();

    rc = pcf50606_write_multiple(0x0a, buf, sizeof(buf));

    restore_irq(oldlevel);

    return rc;
}

/**
 * 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)
{
    int oldlevel = disable_irq_save();
    int rc = pcf50606_read(0x02) & 0x80;
    restore_irq(oldlevel);
    return rc;
}

/**
 * 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.
 */
void rtc_enable_alarm(bool enable)
{
    int oldlevel = disable_irq_save();
    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.
         */
        pcf50606_write_multiple(0x14, alarm_disable + 3, 4);
        /* Unmask the alarm interrupt (might be unneeded) */
        pcf50606_write(0x5, pcf50606_read(0x5) & ~0x80);
        /* Make sure wake on RTC is set when shutting down */
        pcf50606_write(0x8, pcf50606_read(0x8) | 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.
         */
        pcf50606_write(0x17, 0x99);
        /* Make sure we don't wake on RTC after shutting down */
        pcf50606_write(0x8, pcf50606_read(0x8) & ~0x10);
    }
    restore_irq(oldlevel);
    return;
}

/**
 * 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
         */
        int oldlevel = disable_irq_save();
        pcf50606_read_multiple(0x0a, rt, 3);
        pcf50606_read_multiple(0x11, at, 3);
        restore_irq(oldlevel);

        /* 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;
}


/* set alarm time registers to the given time (repeat once per day) */
void rtc_set_alarm(int h, int m)
{
    int oldlevel = disable_irq_save();
    /* Set us to wake at the first second of the specified time */
    pcf50606_write(0x11, 0);
    /* Convert to BCD */
    pcf50606_write(0x12, ((m/10) << 4) | m%10);
    pcf50606_write(0x13, ((h/10) << 4) | h%10);
    restore_irq(oldlevel);
}

/* read out the current alarm time */
void rtc_get_alarm(int *h, int *m)
{
    char buf[2];

    int oldlevel = disable_irq_save();
    pcf50606_read_multiple(0x12, buf, 2);
    restore_irq(oldlevel);
    /* Convert from BCD */
    *m = ((buf[0] >> 4) & 0x7)*10 + (buf[0] & 0x0f);
    *h = ((buf[1] >> 4) & 0x3)*10 + (buf[1] & 0x0f);
}