Diff: targets/TARGET_STM/TARGET_STM32F2/rtc_api.c

Revision:

0:f269e3021894

diff -r 000000000000 -r f269e3021894 targets/TARGET_STM/TARGET_STM32F2/rtc_api.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/TARGET_STM/TARGET_STM32F2/rtc_api.c	Sun Oct 23 15:10:02 2016 +0000
@@ -0,0 +1,222 @@
+/* mbed Microcontroller Library
+ *******************************************************************************
+ * Copyright (c) 2016, STMicroelectronics
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. Neither the name of STMicroelectronics nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *******************************************************************************
+ */
+#include "rtc_api.h"
+
+#if DEVICE_RTC
+
+#include "mbed_error.h"
+
+#if RTC_LSI
+static int rtc_inited = 0;
+#endif
+
+static RTC_HandleTypeDef RtcHandle;
+
+void rtc_init(void)
+{
+    RCC_OscInitTypeDef RCC_OscInitStruct;
+    uint32_t rtc_freq = 0;
+
+#if RTC_LSI
+    rtc_inited = 1;
+#endif
+
+    RtcHandle.Instance = RTC;
+
+#if !RTC_LSI
+    // Enable LSE Oscillator
+    RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSE;
+    RCC_OscInitStruct.PLL.PLLState   = RCC_PLL_NONE; /* Mandatory, otherwise the PLL is reconfigured! */
+    RCC_OscInitStruct.LSEState       = RCC_LSE_ON; /* External 32.768 kHz clock on OSC_IN/OSC_OUT */
+    if (HAL_RCC_OscConfig(&RCC_OscInitStruct) == HAL_OK) {
+        // Connect LSE to RTC
+        __HAL_RCC_RTC_CLKPRESCALER(RCC_RTCCLKSOURCE_LSE);
+        __HAL_RCC_RTC_CONFIG(RCC_RTCCLKSOURCE_LSE);
+        rtc_freq = LSE_VALUE;
+    } else {
+        error("RTC error: LSE clock initialization failed.");
+    }
+#else
+    // Enable Power clock
+    __PWR_CLK_ENABLE();
+
+    // Enable access to Backup domain
+    HAL_PWR_EnableBkUpAccess();
+
+    // Reset Backup domain
+    __HAL_RCC_BACKUPRESET_FORCE();
+    __HAL_RCC_BACKUPRESET_RELEASE();
+
+    // Enable LSI clock
+    RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSI | RCC_OSCILLATORTYPE_LSE;
+    RCC_OscInitStruct.PLL.PLLState   = RCC_PLL_NONE; // Mandatory, otherwise the PLL is reconfigured!
+    RCC_OscInitStruct.LSEState       = RCC_LSE_OFF;
+    RCC_OscInitStruct.LSIState       = RCC_LSI_ON;
+    if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
+        error("RTC error: LSI clock initialization failed.");
+    }
+    // Connect LSI to RTC
+    __HAL_RCC_RTC_CLKPRESCALER(RCC_RTCCLKSOURCE_LSI);
+    __HAL_RCC_RTC_CONFIG(RCC_RTCCLKSOURCE_LSI);
+    // [TODO] This value is LSI typical value. To be measured precisely using a timer input capture
+    rtc_freq = LSI_VALUE;
+#endif
+
+    // Enable RTC
+    __HAL_RCC_RTC_ENABLE();
+
+    RtcHandle.Init.HourFormat     = RTC_HOURFORMAT_24;
+    RtcHandle.Init.AsynchPrediv   = 127;
+    RtcHandle.Init.SynchPrediv    = (rtc_freq / 128) - 1;
+    RtcHandle.Init.OutPut         = RTC_OUTPUT_DISABLE;
+    RtcHandle.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
+    RtcHandle.Init.OutPutType     = RTC_OUTPUT_TYPE_OPENDRAIN;
+
+    if (HAL_RTC_Init(&RtcHandle) != HAL_OK) {
+        error("RTC error: RTC initialization failed.");
+    }
+}
+
+void rtc_free(void)
+{
+#if RTC_LSI
+    // Enable Power clock
+    __PWR_CLK_ENABLE();
+
+    // Enable access to Backup domain
+    HAL_PWR_EnableBkUpAccess();
+
+    // Reset Backup domain
+    __HAL_RCC_BACKUPRESET_FORCE();
+    __HAL_RCC_BACKUPRESET_RELEASE();
+
+    // Disable access to Backup domain
+    HAL_PWR_DisableBkUpAccess();
+#endif
+
+    // Disable LSI and LSE clocks
+    RCC_OscInitTypeDef RCC_OscInitStruct;
+    RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSI | RCC_OSCILLATORTYPE_LSE;
+    RCC_OscInitStruct.PLL.PLLState   = RCC_PLL_NONE;
+    RCC_OscInitStruct.LSIState       = RCC_LSI_OFF;
+    RCC_OscInitStruct.LSEState       = RCC_LSE_OFF;
+    HAL_RCC_OscConfig(&RCC_OscInitStruct);
+#if RTC_LSI
+    rtc_inited = 0;
+#endif
+}
+
+int rtc_isenabled(void)
+{
+#if RTC_LSI
+    return rtc_inited;
+#else
+  if ((RTC->ISR & RTC_ISR_INITS) ==  RTC_ISR_INITS) {
+    return 1;
+  } else {
+    return 0;
+  }
+#endif
+}
+
+/*
+ RTC Registers
+   RTC_WeekDay 1=monday, 2=tuesday, ..., 7=sunday
+   RTC_Month   1=january, 2=february, ..., 12=december
+   RTC_Date    day of the month 1-31
+   RTC_Year    year 0-99
+ struct tm
+   tm_sec      seconds after the minute 0-61
+   tm_min      minutes after the hour 0-59
+   tm_hour     hours since midnight 0-23
+   tm_mday     day of the month 1-31
+   tm_mon      months since January 0-11
+   tm_year     years since 1900
+   tm_wday     days since Sunday 0-6
+   tm_yday     days since January 1 0-365
+   tm_isdst    Daylight Saving Time flag
+*/
+time_t rtc_read(void)
+{
+    RTC_DateTypeDef dateStruct;
+    RTC_TimeTypeDef timeStruct;
+    struct tm timeinfo;
+
+    RtcHandle.Instance = RTC;
+
+    // Read actual date and time
+    // Warning: the time must be read first!
+    HAL_RTC_GetTime(&RtcHandle, &timeStruct, FORMAT_BIN);
+    HAL_RTC_GetDate(&RtcHandle, &dateStruct, FORMAT_BIN);
+
+    // Setup a tm structure based on the RTC
+    timeinfo.tm_wday = dateStruct.WeekDay;
+    timeinfo.tm_mon  = dateStruct.Month - 1;
+    timeinfo.tm_mday = dateStruct.Date;
+    timeinfo.tm_year = dateStruct.Year + 68;
+    timeinfo.tm_hour = timeStruct.Hours;
+    timeinfo.tm_min  = timeStruct.Minutes;
+    timeinfo.tm_sec  = timeStruct.Seconds;
+    timeinfo.tm_isdst  = -1;
+
+    // Convert to timestamp
+    time_t t = mktime(&timeinfo);
+
+    return t;
+}
+
+void rtc_write(time_t t)
+{
+    RTC_DateTypeDef dateStruct;
+    RTC_TimeTypeDef timeStruct;
+
+    RtcHandle.Instance = RTC;
+
+    // Convert the time into a tm
+    struct tm *timeinfo = localtime(&t);
+
+    // Fill RTC structures
+    dateStruct.WeekDay        = timeinfo->tm_wday;
+    dateStruct.Month          = timeinfo->tm_mon + 1;
+    dateStruct.Date           = timeinfo->tm_mday;
+    dateStruct.Year           = timeinfo->tm_year - 68;
+    timeStruct.Hours          = timeinfo->tm_hour;
+    timeStruct.Minutes        = timeinfo->tm_min;
+    timeStruct.Seconds        = timeinfo->tm_sec;
+    timeStruct.TimeFormat     = RTC_HOURFORMAT_24;
+    timeStruct.DayLightSaving = RTC_DAYLIGHTSAVING_NONE;
+    timeStruct.StoreOperation = RTC_STOREOPERATION_RESET;
+
+    // Change the RTC current date/time
+    HAL_RTC_SetDate(&RtcHandle, &dateStruct, FORMAT_BIN);
+    HAL_RTC_SetTime(&RtcHandle, &timeStruct, FORMAT_BIN);
+}
+
+#endif