flight/pios/stm32f10x/pios_rtc.c

   1 /**
   2  ******************************************************************************
   3  * @addtogroup PIOS PIOS Core hardware abstraction layer
   4  * @{
   5  * @addtogroup   PIOS_PWM PWM Input Functions
   6  * @brief               Code to measure with PWM input
   7  * @{
   8  *
   9  * @file       pios_pwm.c
  10  * @author     The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010.
  11  * @brief      PWM Input functions (STM32 dependent)
  12  * @see        The GNU Public License (GPL) Version 3
  13  *
  14  *****************************************************************************/
  15 /*
  16  * This program is free software; you can redistribute it and/or modify
  17  * it under the terms of the GNU General Public License as published by
  18  * the Free Software Foundation; either version 3 of the License, or
  19  * (at your option) any later version.
  20  *
  21  * This program is distributed in the hope that it will be useful, but
  22  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  23  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  24  * for more details.
  25  *
  26  * You should have received a copy of the GNU General Public License along
  27  * with this program; if not, write to the Free Software Foundation, Inc.,
  28  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  29  */
  30
  31 #include "pios.h"
  32
  33 #ifdef PIOS_INCLUDE_RTC
  34
  35 #include <pios_rtc_priv.h>
  36
  37 #ifndef PIOS_RTC_PRESCALER
  38 #define PIOS_RTC_PRESCALER 100
  39 #endif
  40
  41 struct rtc_callback_entry {
  42     void     (*fn)(uint32_t);
  43     uint32_t data;
  44 };
  45
  46 #define PIOS_RTC_MAX_CALLBACKS 3
  47 struct rtc_callback_entry rtc_callback_list[PIOS_RTC_MAX_CALLBACKS];
  48 static uint8_t rtc_callback_next = 0;
  49
  50 void PIOS_RTC_Init(const struct pios_rtc_cfg *cfg)
  51 {
  52     RCC_APB1PeriphClockCmd(RCC_APB1Periph_BKP | RCC_APB1Periph_PWR,
  53                            ENABLE);
  54     PWR_BackupAccessCmd(ENABLE);
  55
  56     RCC_RTCCLKConfig(cfg->clksrc);
  57     RCC_RTCCLKCmd(ENABLE);
  58     RTC_WaitForLastTask();
  59     RTC_WaitForSynchro();
  60     RTC_WaitForLastTask();
  61
  62     /* Configure and enable the RTC Second interrupt */
  63     NVIC_Init(&cfg->irq.init);
  64     RTC_ITConfig(RTC_IT_SEC, ENABLE);
  65     RTC_WaitForLastTask();
  66
  67     RTC_SetPrescaler(cfg->prescaler);
  68     RTC_WaitForLastTask();
  69     RTC_SetCounter(0);
  70     RTC_WaitForLastTask();
  71 }
  72
  73 uint32_t PIOS_RTC_Counter()
  74 {
  75     return RTC_GetCounter();
  76 }
  77
  78 /* FIXME: This shouldn't use hard-coded clock rates, dividers or prescalers.
  79  *        Should get these from the cfg struct passed to init.
  80  */
  81 float PIOS_RTC_Rate()
  82 {
  83     return (float)(8e6f / 128.0f) / (1 + PIOS_RTC_PRESCALER);
  84 }
  85
  86 float PIOS_RTC_MsPerTick()
  87 {
  88     return 1000.0f / PIOS_RTC_Rate();
  89 }
  90
  91 /* TODO: This needs a mutex around rtc_callbacks[] */
  92 bool PIOS_RTC_RegisterTickCallback(void (*fn)(uint32_t id), uint32_t data)
  93 {
  94     struct rtc_callback_entry *cb;
  95
  96     if (rtc_callback_next >= PIOS_RTC_MAX_CALLBACKS) {
  97         return false;
  98     }
  99
 100     cb       = &rtc_callback_list[rtc_callback_next++];
 101
 102     cb->fn   = fn;
 103     cb->data = data;
 104     return true;
 105 }
 106
 107 void PIOS_RTC_irq_handler(void)
 108 {
 109     if (RTC_GetITStatus(RTC_IT_SEC)) {
 110         /* Call all registered callbacks */
 111         for (uint8_t i = 0; i < rtc_callback_next; i++) {
 112             struct rtc_callback_entry *cb = &rtc_callback_list[i];
 113             if (cb->fn) {
 114                 (cb->fn)(cb->data);
 115             }
 116         }
 117
 118         /* Wait until last write operation on RTC registers has finished */
 119         RTC_WaitForLastTask();
 120         /* Clear the RTC Second interrupt */
 121         RTC_ClearITPendingBit(RTC_IT_SEC);
 122     }
 123 }
 124
 125 #endif /* PIOS_INCLUDE_RTC */
 126
 127 /**
 128  * @}
 129  * @}
 130  */