[HAL][RTC] Check if the RTC calendar has been previously initialized before entering Initialization mode
diff --git a/Inc/stm32l4xx_hal_rtc.h b/Inc/stm32l4xx_hal_rtc.h
index 99c1658..428c5ad 100644
--- a/Inc/stm32l4xx_hal_rtc.h
+++ b/Inc/stm32l4xx_hal_rtc.h
@@ -641,6 +641,17 @@
} while(0u)
/**
+ * @brief Check whether if the RTC Calendar is initialized.
+ * @param __HANDLE__ specifies the RTC handle.
+ * @retval None
+ */
+#if defined(STM32L412xx) || defined(STM32L422xx) || defined (STM32L4P5xx) || defined (STM32L4Q5xx)
+#define __HAL_RTC_IS_CALENDAR_INITIALIZED(__HANDLE__) ((((RTC->ICSR) & (RTC_ICSR_INITS)) == RTC_ICSR_INITS) ? 1U : 0U)
+#else
+#define __HAL_RTC_IS_CALENDAR_INITIALIZED(__HANDLE__) (((((__HANDLE__)->Instance->ISR) & (RTC_FLAG_INITS)) == RTC_FLAG_INITS) ? 1U : 0U)
+#endif /* #if defined(STM32L412xx) || defined(STM32L422xx) || defined (STM32L4P5xx) || defined (STM32L4Q5xx) */
+
+/**
* @brief Add 1 hour (summer time change).
* @note This interface is deprecated.
* To manage Daylight Saving Time, please use HAL_RTC_DST_xxx functions
diff --git a/Src/stm32l4xx_hal_rtc.c b/Src/stm32l4xx_hal_rtc.c
index d0c9f1b..666fe93 100644
--- a/Src/stm32l4xx_hal_rtc.c
+++ b/Src/stm32l4xx_hal_rtc.c
@@ -319,32 +319,36 @@
/* Set RTC state */
hrtc->State = HAL_RTC_STATE_BUSY;
- /* Disable the write protection for RTC registers */
- __HAL_RTC_WRITEPROTECTION_DISABLE(hrtc);
-
- /* Enter Initialization mode */
- status = RTC_EnterInitMode(hrtc);
-
- if (status == HAL_OK)
+ /* Check whether the calendar needs to be initialized */
+ if (__HAL_RTC_IS_CALENDAR_INITIALIZED(hrtc) == 0U)
{
-#if defined(STM32L412xx) || defined(STM32L422xx) || defined (STM32L4P5xx) || defined (STM32L4Q5xx)
- /* Clear RTC_CR FMT, OSEL, POL and TAMPOE Bits */
- hrtc->Instance->CR &= ~(RTC_CR_FMT | RTC_CR_POL | RTC_CR_OSEL | RTC_CR_TAMPOE);
-#else
- /* Clear RTC_CR FMT, OSEL and POL Bits */
- hrtc->Instance->CR &= ~(RTC_CR_FMT | RTC_CR_OSEL | RTC_CR_POL);
-#endif
- /* Set RTC_CR register */
- hrtc->Instance->CR |= (hrtc->Init.HourFormat | hrtc->Init.OutPut | hrtc->Init.OutPutPolarity);
+ /* Disable the write protection for RTC registers */
+ __HAL_RTC_WRITEPROTECTION_DISABLE(hrtc);
- /* Configure the RTC PRER */
- hrtc->Instance->PRER = (hrtc->Init.SynchPrediv);
- hrtc->Instance->PRER |= (hrtc->Init.AsynchPrediv << RTC_PRER_PREDIV_A_Pos);
+ /* Enter Initialization mode */
+ status = RTC_EnterInitMode(hrtc);
+
+ if (status == HAL_OK)
+ {
+#if defined(STM32L412xx) || defined(STM32L422xx) || defined (STM32L4P5xx) || defined (STM32L4Q5xx)
+ /* Clear RTC_CR FMT, OSEL, POL and TAMPOE Bits */
+ hrtc->Instance->CR &= ~(RTC_CR_FMT | RTC_CR_POL | RTC_CR_OSEL | RTC_CR_TAMPOE);
+#else
+ /* Clear RTC_CR FMT, OSEL and POL Bits */
+ hrtc->Instance->CR &= ~(RTC_CR_FMT | RTC_CR_OSEL | RTC_CR_POL);
+#endif
+ /* Set RTC_CR register */
+ hrtc->Instance->CR |= (hrtc->Init.HourFormat | hrtc->Init.OutPut | hrtc->Init.OutPutPolarity);
+
+ /* Configure the RTC PRER */
+ hrtc->Instance->PRER = (hrtc->Init.SynchPrediv);
+ hrtc->Instance->PRER |= (hrtc->Init.AsynchPrediv << RTC_PRER_PREDIV_A_Pos);
#if defined (STM32L4P5xx) || defined (STM32L4Q5xx)
- /* Configure the Binary mode */
- MODIFY_REG(RTC->ICSR, RTC_ICSR_BIN | RTC_ICSR_BCDU, hrtc->Init.BinMode | hrtc->Init.BinMixBcdU);
+ /* Configure the Binary mode */
+ MODIFY_REG(RTC->ICSR, RTC_ICSR_BIN | RTC_ICSR_BCDU, hrtc->Init.BinMode | hrtc->Init.BinMixBcdU);
#endif
+ }
/* Exit Initialization mode */
status = RTC_ExitInitMode(hrtc);
@@ -358,12 +362,20 @@
hrtc->Instance->OR &= ~(RTC_OR_ALARMOUTTYPE | RTC_OR_OUT_RMP);
hrtc->Instance->OR |= (hrtc->Init.OutPutType | hrtc->Init.OutPutRemap);
#endif
-
- /* Enable the write protection for RTC registers */
- __HAL_RTC_WRITEPROTECTION_ENABLE(hrtc);
-
- hrtc->State = HAL_RTC_STATE_READY;
}
+
+ /* Enable the write protection for RTC registers */
+ __HAL_RTC_WRITEPROTECTION_ENABLE(hrtc);
+ }
+ else
+ {
+ /* The calendar is already initialized */
+ status = HAL_OK;
+ }
+
+ if (status == HAL_OK)
+ {
+ hrtc->State = HAL_RTC_STATE_READY;
}
}
