drivers/rtc/ftrtc010.c

   1 /*
   2  * Faraday FTRTC010 Real Time Clock
   3  *
   4  * (C) Copyright 2009 Faraday Technology
   5  * Po-Yu Chuang <ratbert@faraday-tech.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  */
  21
  22 #include <config.h>
  23 #include <common.h>
  24 #include <rtc.h>
  25 #include <asm/io.h>
  26
  27 struct ftrtc010 {
  28         unsigned int sec;               /* 0x00 */
  29         unsigned int min;               /* 0x04 */
  30         unsigned int hour;              /* 0x08 */
  31         unsigned int day;               /* 0x0c */
  32         unsigned int alarm_sec;         /* 0x10 */
  33         unsigned int alarm_min;         /* 0x14 */
  34         unsigned int alarm_hour;        /* 0x18 */
  35         unsigned int record;            /* 0x1c */
  36         unsigned int cr;                /* 0x20 */
  37 };
  38
  39 /*
  40  * RTC Control Register
  41  */
  42 #define FTRTC010_CR_ENABLE              (1 << 0)
  43 #define FTRTC010_CR_INTERRUPT_SEC       (1 << 1)        /* per second irq */
  44 #define FTRTC010_CR_INTERRUPT_MIN       (1 << 2)        /* per minute irq */
  45 #define FTRTC010_CR_INTERRUPT_HR        (1 << 3)        /* per hour   irq */
  46 #define FTRTC010_CR_INTERRUPT_DAY       (1 << 4)        /* per day    irq */
  47
  48 static struct ftrtc010 *rtc = (struct ftrtc010 *)CONFIG_FTRTC010_BASE;
  49
  50 static void ftrtc010_enable(void)
  51 {
  52         writel(FTRTC010_CR_ENABLE, &rtc->cr);
  53 }
  54
  55 /*
  56  * return current time in seconds
  57  */
  58 static unsigned long ftrtc010_time(void)
  59 {
  60         unsigned long day;
  61         unsigned long hour;
  62         unsigned long minute;
  63         unsigned long second;
  64         unsigned long second2;
  65
  66         do {
  67                 second  = readl(&rtc->sec);
  68                 day     = readl(&rtc->day);
  69                 hour    = readl(&rtc->hour);
  70                 minute  = readl(&rtc->min);
  71                 second2 = readl(&rtc->sec);
  72         } while (second != second2);
  73
  74         return day * 24 * 60 * 60 + hour * 60 * 60 + minute * 60 + second;
  75 }
  76
  77 /*
  78  * Get the current time from the RTC
  79  */
  80
  81 int rtc_get(struct rtc_time *tmp)
  82 {
  83         unsigned long now;
  84
  85         debug("%s(): record register: %x\n",
  86               __func__, readl(&rtc->record));
  87
  88         now = ftrtc010_time() + readl(&rtc->record);
  89
  90         to_tm(now, tmp);
  91
  92         return 0;
  93 }
  94
  95 /*
  96  * Set the RTC
  97  */
  98 int rtc_set(struct rtc_time *tmp)
  99 {
 100         unsigned long new;
 101         unsigned long now;
 102
 103         debug("%s(): DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 104               __func__,
 105               tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 106               tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
 107
 108         new = mktime(tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_hour,
 109                      tmp->tm_min, tmp->tm_sec);
 110
 111         now = ftrtc010_time();
 112
 113         debug("%s(): write %lx to record register\n", __func__, new - now);
 114
 115         writel(new - now, &rtc->record);
 116
 117         return 0;
 118 }
 119
 120 void rtc_reset(void)
 121 {
 122         debug("%s()\n", __func__);
 123         ftrtc010_enable();
 124 }