firmware/drivers/rtc/rtc_e8564.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2002 by Linus Nielsen Feltzing, Uwe Freese, Laurent Baum,
  11  *                       Przemyslaw Holubowski
  12  *
  13  * This program is free software; you can redistribute it and/or
  14  * modify it under the terms of the GNU General Public License
  15  * as published by the Free Software Foundation; either version 2
  16  * of the License, or (at your option) any later version.
  17  *
  18  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  19  * KIND, either express or implied.
  20  *
  21  ****************************************************************************/
  22 #include "config.h"
  23 #include "i2c.h"
  24 #include "rtc.h"
  25 #include "kernel.h"
  26 #include "system.h"
  27 #include "i2c-pp.h"
  28 #include <stdbool.h>
  29
  30 /* RTC registers */
  31 #define RTC_CTRL1          0x00
  32 #define RTC_CTRL2          0x01
  33 #define RTC_ALARM_MINUTES  0x09
  34 #define RTC_ALARM_HOURS    0x0A
  35 #define RTC_ALARM_DAY      0x0B
  36 #define RTC_ALARM_WDAY     0x0C
  37 #define RTC_TIMER_CTRL     0x0E
  38 #define RTC_TIMER          0x0F
  39
  40 /* Control 2 register flags */
  41 #define RTC_TIE    0x01
  42 #define RTC_AIE    0x02
  43 #define RTC_TF     0x04
  44 #define RTC_AF     0x08
  45 #define RTC_TI_TP  0x10
  46
  47 /* Alarm registers flags */
  48 #define RTC_AE     0x80
  49
  50 /* Timer register flags */
  51 #define RTC_TE     0x80
  52
  53 bool rtc_lock_alarm_clear=true;
  54
  55 void rtc_init(void)
  56 {
  57     unsigned char tmp;
  58     int rv;
  59
  60     /* initialize Control 1 register */
  61     tmp = 0;
  62     pp_i2c_send(0x51, RTC_CTRL1,tmp);
  63
  64     /* read value of the Control 2 register - we'll need it to preserve alarm and timer interrupt assertion flags */
  65     rv = i2c_readbytes(0x51,RTC_CTRL2,1,&tmp);
  66     /* preserve alarm and timer interrupt flags */
  67     tmp &= (RTC_TF | RTC_AF | RTC_TIE | RTC_AIE);
  68     pp_i2c_send(0x51, RTC_CTRL2,tmp);
  69 }
  70
  71 int rtc_read_datetime(unsigned char* buf)
  72 {
  73     unsigned char tmp;
  74     int read;
  75
  76     /*RTC_E8564's slave address is 0x51*/
  77     read = i2c_readbytes(0x51,0x02,7,buf);
  78
  79     /* swap wday and mday to be compatible with
  80      * get_time() from firmware/common/timefuncs.c */
  81     tmp=buf[3];
  82     buf[3]=buf[4];
  83     buf[4]=tmp;
  84
  85     return read;
  86 }
  87
  88 int rtc_write_datetime(unsigned char* buf)
  89 {
  90     int i;
  91     unsigned char tmp;
  92
  93     /* swap wday and mday to be compatible with
  94      * set_time() in firmware/common/timefuncs.c */
  95     tmp=buf[3];
  96     buf[3]=buf[4];
  97     buf[4]=tmp;
  98
  99     for (i=0;i<7;i++){
 100         pp_i2c_send(0x51, 0x02+i,buf[i]);
 101     }
 102     return 1;
 103 }
 104
 105 void rtc_set_alarm(int h, int m)
 106 {
 107     unsigned char buf[4]={0};
 108     int rv=0;
 109     int i=0;
 110
 111     /* clear alarm interrupt */
 112     rv = i2c_readbytes(0x51,RTC_CTRL2,1,buf);
 113     buf[0] &= RTC_AF;
 114     pp_i2c_send(0x51, RTC_CTRL2,buf[0]);
 115
 116     /* prepare new alarm */
 117     if( m >= 0 )
 118         buf[0] = (((m/10) << 4) | m%10);
 119     else
 120         /* ignore minutes comparison query */
 121         buf[0] = RTC_AE;
 122
 123     if( h >= 0 )
 124         buf[1] = (((h/10) << 4) | h%10);
 125     else
 126         /* ignore hours comparison query */
 127         buf[1] = RTC_AE;
 128
 129     /* ignore day and wday */
 130     buf[2] = RTC_AE;
 131     buf[3] = RTC_AE;
 132
 133     /* write new alarm */
 134     for(;i<4;i++)
 135         pp_i2c_send(0x51, RTC_ALARM_MINUTES+i,buf[i]);
 136
 137     /* note: alarm is not enabled at the point */
 138 }
 139
 140 void rtc_get_alarm(int *h, int *m)
 141 {
 142     unsigned char buf[4]={0};
 143
 144     /* get alarm preset */
 145     i2c_readbytes(0x51, RTC_ALARM_MINUTES,4,buf);
 146
 147     *m = ((buf[0] >> 4) & 0x7)*10 + (buf[0] & 0x0f);
 148     *h = ((buf[1] >> 4) & 0x3)*10 + (buf[1] & 0x0f);
 149
 150 }
 151
 152 bool rtc_enable_alarm(bool enable)
 153 {
 154     unsigned char tmp=0;
 155     int rv=0;
 156
 157     if(enable)
 158     {
 159         /* enable alarm interrupt */
 160         rv = i2c_readbytes(0x51,RTC_CTRL2,1,&tmp);
 161         tmp |= RTC_AIE;
 162         tmp &= ~RTC_AF;
 163         pp_i2c_send(0x51, RTC_CTRL2,tmp);
 164     }
 165     else
 166     {
 167         /* disable alarm interrupt */
 168         if(rtc_lock_alarm_clear)
 169             /* lock disabling alarm before it was checked whether or not the unit was started by RTC alarm */
 170             return false;
 171         rv = i2c_readbytes(0x51,RTC_CTRL2,1,&tmp);
 172         tmp &= ~(RTC_AIE | RTC_AF);
 173         pp_i2c_send(0x51, RTC_CTRL2,tmp);
 174     }
 175
 176     return false;
 177 }
 178
 179 bool rtc_check_alarm_started(bool release_alarm)
 180 {
 181     static bool alarm_state, run_before = false;
 182     unsigned char tmp=0;
 183     bool started;
 184     int rv=0;
 185
 186     if (run_before)
 187     {
 188         started = alarm_state;
 189         alarm_state &= ~release_alarm;
 190     }
 191     else
 192     {
 193         /* read Control 2 register which contains alarm flag */
 194         rv = i2c_readbytes(0x51,RTC_CTRL2,1,&tmp);
 195
 196         alarm_state = started = ( (tmp & RTC_AF) && (tmp & RTC_AIE) );
 197
 198         if(release_alarm && started)
 199         {
 200             rv = i2c_readbytes(0x51,RTC_CTRL2,1,&tmp);
 201             /* clear alarm interrupt enable and alarm flag */
 202             tmp &= ~(RTC_AF | RTC_AIE);
 203             pp_i2c_send(0x51, RTC_CTRL2,tmp);
 204         }
 205         run_before = true;
 206         rtc_lock_alarm_clear = false;
 207     }
 208
 209     return started;
 210 }
 211
 212 bool rtc_check_alarm_flag(void)
 213 {
 214     unsigned char tmp=0;
 215     int rv=0;
 216
 217     /* read Control 2 register which contains alarm flag */
 218     rv = i2c_readbytes(0x51,RTC_CTRL2,1,&tmp);
 219
 220     return (tmp & RTC_AF);
 221 }