Blame view

RIOT/cpu/samd21/periph/rtc.c 6.47 KB
a752c7ab   elopes   add first test an...
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
  /*
   * Copyright (C) 2014 Baptiste CLENET
   *
   * This file is subject to the terms and conditions of the GNU Lesser
   * General Public License v2.1. See the file LICENSE in the top level
   * directory for more details.
   */
  
  /**
   * @ingroup     cpu_samd21
   * @ingroup     drivers_periph_rtc
   * @{
   *
   * @file
   * @brief       Low-level RTC driver implementation
   *
   * @author      Baptiste Clenet <bapclenet@gmail.com>
   *
   * @}
   */
  
  #include <time.h>
  #include "cpu.h"
  #include "periph/rtc.h"
  #include "periph_conf.h"
  
  /* guard file in case no RTC device was specified */
  #if RTC_NUMOF
  
  typedef struct {
      rtc_alarm_cb_t cb;        /**< callback called from RTC interrupt */
      void *arg;                /**< argument passed to the callback */
  } rtc_state_t;
  
  static rtc_state_t rtc_callback;
  
  /* At 1Hz, RTC goes till 63 years (2^5, see 17.8.22 in datasheet)
  * reference_year is set to 100 (offset) to be in our current time (2000)
  * Thanks to this, the user will be able to set time in 2000's*/
  static uint16_t reference_year = 100;
  
  void rtc_init(void)
  {
      RtcMode2 *rtcMode2 = &(RTC_DEV);
  
      /* Turn on power manager for RTC */
      PM->APBAMASK.reg |= PM_APBAMASK_RTC;
  
      /* RTC uses External 32,768KHz Oscillator (OSC32K isn't accurate enough p1075/1138)*/
      SYSCTRL->XOSC32K.reg =  SYSCTRL_XOSC32K_ONDEMAND |
                              SYSCTRL_XOSC32K_EN32K |
                              SYSCTRL_XOSC32K_XTALEN |
                              SYSCTRL_XOSC32K_STARTUP(6) |
                              SYSCTRL_XOSC32K_ENABLE;
  
      /* Setup clock GCLK2 with OSC32K divided by 32 */
      GCLK->GENDIV.reg = GCLK_GENDIV_ID(2)|GCLK_GENDIV_DIV(4);
      while (GCLK->STATUS.reg & GCLK_STATUS_SYNCBUSY) {}
      GCLK->GENCTRL.reg = (GCLK_GENCTRL_GENEN | GCLK_GENCTRL_SRC_XOSC32K | GCLK_GENCTRL_ID(2) | GCLK_GENCTRL_DIVSEL );
      while (GCLK->STATUS.reg & GCLK_STATUS_SYNCBUSY) {}
      GCLK->CLKCTRL.reg = (uint32_t)((GCLK_CLKCTRL_CLKEN | GCLK_CLKCTRL_GEN_GCLK2 | (RTC_GCLK_ID << GCLK_CLKCTRL_ID_Pos)));
      while (GCLK->STATUS.bit.SYNCBUSY) {}
  
      /* DISABLE RTC MASTER */
      while (rtcMode2->STATUS.reg & RTC_STATUS_SYNCBUSY) {}
      rtc_poweroff();
  
      /* Reset RTC */
      while (rtcMode2->STATUS.bit.SYNCBUSY) {}
      rtcMode2->CTRL.reg= RTC_MODE2_CTRL_SWRST;
      while (rtcMode2->STATUS.bit.SYNCBUSY) {}
  
      /* RTC config with RTC_MODE2_CTRL_CLKREP = 0 (24h) */
      rtcMode2->CTRL.reg = RTC_MODE2_CTRL_PRESCALER_DIV1024|RTC_MODE2_CTRL_MODE_CLOCK;
      while (rtcMode2->STATUS.bit.SYNCBUSY) {}
      rtcMode2->INTENSET.reg = RTC_MODE2_INTENSET_OVF;
      while (rtcMode2->STATUS.bit.SYNCBUSY) {}
      rtc_poweron();
  }
  
  int rtc_set_time(struct tm *time)
  {
      RtcMode2 *rtcMode2 = &(RTC_DEV);
      if ((time->tm_year < reference_year) || (time->tm_year > reference_year + 63)) {
          return -1;
      }
      else {
          rtcMode2->CLOCK.reg = RTC_MODE2_CLOCK_YEAR(time->tm_year - reference_year)
                  | RTC_MODE2_CLOCK_MONTH(time->tm_mon + 1)
                  | RTC_MODE2_CLOCK_DAY(time->tm_mday)
                  | RTC_MODE2_CLOCK_HOUR(time->tm_hour)
                  | RTC_MODE2_CLOCK_MINUTE(time->tm_min)
                  | RTC_MODE2_CLOCK_SECOND(time->tm_sec);
      }
      while (rtcMode2->STATUS.bit.SYNCBUSY) {}
      return 0;
  }
  
  int rtc_get_time(struct tm *time)
  {
      RtcMode2 *rtcMode2 = &(RTC_DEV);
      time->tm_year = rtcMode2->CLOCK.bit.YEAR + reference_year;
      if ((time->tm_year < reference_year) || (time->tm_year > (reference_year + 63))) {
          return -1;
      }
      time->tm_mon = rtcMode2->CLOCK.bit.MONTH - 1;
      time->tm_mday = rtcMode2->CLOCK.bit.DAY;
      time->tm_hour = rtcMode2->CLOCK.bit.HOUR;
      time->tm_min = rtcMode2->CLOCK.bit.MINUTE;
      time->tm_sec = rtcMode2->CLOCK.bit.SECOND;
      while (rtcMode2->STATUS.bit.SYNCBUSY) {}
      return 0;
  }
  
  int rtc_set_alarm(struct tm *time, rtc_alarm_cb_t cb, void *arg)
  {
      RtcMode2 *rtcMode2 = &(RTC_DEV);
      rtc_clear_alarm();
      if ((time->tm_year < reference_year) || (time->tm_year > (reference_year + 63))) {
          return -2;
      }
      else {
          rtcMode2->Mode2Alarm[0].ALARM.reg = RTC_MODE2_ALARM_YEAR(time->tm_year - reference_year)
                  | RTC_MODE2_ALARM_MONTH(time->tm_mon + 1)
                  | RTC_MODE2_ALARM_DAY(time->tm_mday)
                  | RTC_MODE2_ALARM_HOUR(time->tm_hour)
                  | RTC_MODE2_ALARM_MINUTE(time->tm_min)
                  | RTC_MODE2_ALARM_SECOND(time->tm_sec);
          rtcMode2->Mode2Alarm[0].MASK.reg = RTC_MODE2_MASK_SEL(6);
      }
      while (rtcMode2->STATUS.bit.SYNCBUSY) {}
  
      /* Setup interrupt */
      NVIC_EnableIRQ(RTC_IRQn);
  
      /* Enable IRQ */
      rtc_callback.cb = cb;
      rtc_callback.arg = arg;
      rtcMode2->INTFLAG.reg = RTC_MODE2_INTFLAG_ALARM0;
      while (rtcMode2->STATUS.bit.SYNCBUSY) {}
      rtcMode2->INTENSET.reg = RTC_MODE2_INTENSET_ALARM0;
      while (rtcMode2->STATUS.bit.SYNCBUSY) {}
  
      return 0;
  }
  
  int rtc_get_alarm(struct tm *time)
  {
      RtcMode2 *rtcMode2 = &(RTC_DEV);
      time->tm_year = rtcMode2->Mode2Alarm[0].ALARM.bit.YEAR + reference_year;
      if ((time->tm_year < reference_year) || (time->tm_year > (reference_year + 63))) {
          return -1;
      }
      time->tm_mon = rtcMode2->Mode2Alarm[0].ALARM.bit.MONTH - 1;
      time->tm_mday = rtcMode2->Mode2Alarm[0].ALARM.bit.DAY;
      time->tm_hour = rtcMode2->Mode2Alarm[0].ALARM.bit.HOUR;
      time->tm_min = rtcMode2->Mode2Alarm[0].ALARM.bit.MINUTE;
      time->tm_sec = rtcMode2->Mode2Alarm[0].ALARM.bit.SECOND;
      while(rtcMode2->STATUS.bit.SYNCBUSY) {}
      return 0;
  }
  
  void rtc_clear_alarm(void)
  {
      RtcMode2 *rtcMode2 = &(RTC_DEV);
      /* Disable IRQ */
      rtcMode2->INTENCLR.reg = RTC_MODE2_INTENCLR_ALARM0;
      rtc_callback.cb = NULL;
      rtc_callback.arg = NULL;
  }
  
  void rtc_poweron(void)
  {
      RtcMode2 *rtcMode2 = &(RTC_DEV);
      rtcMode2->CTRL.bit.ENABLE = 1;
      while (rtcMode2->STATUS.bit.SYNCBUSY) {}
  }
  
  void rtc_poweroff(void)
  {
      RtcMode2 *rtcMode2 = &(RTC_DEV);
      rtcMode2->CTRL.bit.ENABLE = 0;
      while (rtcMode2->STATUS.bit.SYNCBUSY) {}
  }
  
  void isr_rtc(void)
  {
      RtcMode2 *rtcMode2 = &(RTC_DEV);
      uint16_t status = rtcMode2->INTFLAG.reg;
      if ((status & RTC_MODE2_INTFLAG_ALARM0) && (rtc_callback.cb != NULL)) {
          rtc_callback.cb(rtc_callback.arg);
          rtcMode2->INTFLAG.reg = RTC_MODE2_INTFLAG_ALARM0;
      }
      if (status & RTC_MODE2_INTFLAG_OVF) {
          /* At 1Hz, RTC goes till 63 years (2^5, see 17.8.22 in datasheet)
          * Start RTC again with reference_year 64 years more (Be careful with alarm set) */
          reference_year += 64;
          rtcMode2->INTFLAG.reg = RTC_MODE2_INTFLAG_OVF;
      }
      cortexm_isr_end();
  }
  
  #endif /* RTC_NUMOF */