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         unsigned int wsec;              /* 0x24 */
  38         unsigned int wmin;              /* 0x28 */
  39         unsigned int whour;             /* 0x2c */
  40         unsigned int wday;              /* 0x30 */
  41         unsigned int intr;              /* 0x34 */
  42         unsigned int div;               /* 0x38 */
  43         unsigned int rev;               /* 0x3c */
  44 };
  45
  46 /*
  47  * RTC Control Register
  48  */
  49 #define FTRTC010_CR_ENABLE              (1 << 0)
  50 #define FTRTC010_CR_INTERRUPT_SEC       (1 << 1)        /* per second irq */
  51 #define FTRTC010_CR_INTERRUPT_MIN       (1 << 2)        /* per minute irq */
  52 #define FTRTC010_CR_INTERRUPT_HR        (1 << 3)        /* per hour   irq */
  53 #define FTRTC010_CR_INTERRUPT_DAY       (1 << 4)        /* per day    irq */
  54
  55 static struct ftrtc010 *rtc = (struct ftrtc010 *)CONFIG_FTRTC010_BASE;
  56
  57 static void ftrtc010_enable(void)
  58 {
  59         writel(FTRTC010_CR_ENABLE, &rtc->cr);
  60 }
  61
  62 /*
  63  * return current time in seconds
  64  */
  65 static unsigned long ftrtc010_time(void)
  66 {
  67         unsigned long day;
  68         unsigned long hour;
  69         unsigned long minute;
  70         unsigned long second;
  71         unsigned long second2;
  72
  73         do {
  74                 second  = readl(&rtc->sec);
  75                 day     = readl(&rtc->day);
  76                 hour    = readl(&rtc->hour);
  77                 minute  = readl(&rtc->min);
  78                 second2 = readl(&rtc->sec);
  79         } while (second != second2);
  80
  81         return day * 24 * 60 * 60 + hour * 60 * 60 + minute * 60 + second;
  82 }
  83
  84 /*
  85  * Get the current time from the RTC
  86  */
  87
  88 int rtc_get(struct rtc_time *tmp)
  89 {
  90         unsigned long now;
  91
  92         debug("%s(): record register: %x\n",
  93               __func__, readl(&rtc->record));
  94
  95 #ifdef CONFIG_FTRTC010_PCLK
  96         now = (ftrtc010_time() + readl(&rtc->record)) / RTC_DIV_COUNT;
  97 #else /* CONFIG_FTRTC010_EXTCLK */
  98         now = ftrtc010_time() + readl(&rtc->record);
  99 #endif
 100
 101         to_tm(now, tmp);
 102
 103         return 0;
 104 }
 105
 106 /*
 107  * Set the RTC
 108  */
 109 int rtc_set(struct rtc_time *tmp)
 110 {
 111         unsigned long new;
 112         unsigned long now;
 113
 114         debug("%s(): DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 115               __func__,
 116               tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 117               tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
 118
 119         new = mktime(tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_hour,
 120                      tmp->tm_min, tmp->tm_sec);
 121
 122         now = ftrtc010_time();
 123
 124         debug("%s(): write %lx to record register\n", __func__, new - now);
 125
 126         writel(new - now, &rtc->record);
 127
 128         return 0;
 129 }
 130
 131 void rtc_reset(void)
 132 {
 133         debug("%s()\n", __func__);
 134         ftrtc010_enable();
 135 }