drivers: rtc: stm32: Fixes RTC issues related to device runtime pm

When device runtime pm is enabled, Backup Domain protection is active most of the time. RTC driver need this protection to be disabled in order to set the time or calibration. This fix disable the protection in set time and set calibration functions. Fixes: 62843 Signed-off-by: Petr Hlineny <[email protected]>
iotbzh · Jan 4, 2024 · 4a45435 · 4a45435
1 parent 21e3749
commit 4a45435
Showing 1 changed file with 24 additions and 0 deletions.
diff --git a/drivers/rtc/rtc_ll_stm32.c b/drivers/rtc/rtc_ll_stm32.c
@@ -181,6 +181,10 @@ static int rtc_stm32_init(const struct device *dev)
 
 	err = rtc_stm32_configure(dev);
 
+#if defined(PWR_CR_DBP) || defined(PWR_CR1_DBP) || defined(PWR_DBPCR_DBP) || defined(PWR_DBPR_DBP)
+	LL_PWR_DisableBkUpAccess();
+#endif /* PWR_CR_DBP || PWR_CR1_DBP || PWR_DBPR_DBP */
+
 	return err;
 }
 
@@ -208,10 +212,18 @@ static int rtc_stm32_set_time(const struct device *dev, const struct rtc_time *t
 	}
 
 	LOG_INF("Setting clock");
+
+#if defined(PWR_CR_DBP) || defined(PWR_CR1_DBP) || defined(PWR_DBPCR_DBP) || defined(PWR_DBPR_DBP)
+	LL_PWR_EnableBkUpAccess();
+#endif /* PWR_CR_DBP || PWR_CR1_DBP || PWR_DBPR_DBP */
+
 	LL_RTC_DisableWriteProtection(RTC);
 
 	err = rtc_stm32_enter_initialization_mode(true);
 	if (err) {
+#if defined(PWR_CR_DBP) || defined(PWR_CR1_DBP) || defined(PWR_DBPCR_DBP) || defined(PWR_DBPR_DBP)
+		LL_PWR_DisableBkUpAccess();
+#endif /* PWR_CR_DBP || PWR_CR1_DBP || PWR_DBPR_DBP */
 		k_mutex_unlock(&data->lock);
 		return err;
 	}
@@ -237,6 +249,10 @@ static int rtc_stm32_set_time(const struct device *dev, const struct rtc_time *t
 
 	LL_RTC_EnableWriteProtection(RTC);
 
+#if defined(PWR_CR_DBP) || defined(PWR_CR1_DBP) || defined(PWR_DBPCR_DBP) || defined(PWR_DBPR_DBP)
+	LL_PWR_DisableBkUpAccess();
+#endif /* PWR_CR_DBP || PWR_CR1_DBP || PWR_DBPR_DBP */
+
 	k_mutex_unlock(&data->lock);
 
 	return err;
@@ -359,12 +375,20 @@ static int rtc_stm32_set_calibration(const struct device *dev, int32_t calibrati
 		return -EIO;
 	}
 
+#if defined(PWR_CR_DBP) || defined(PWR_CR1_DBP) || defined(PWR_DBPCR_DBP) || defined(PWR_DBPR_DBP)
+	LL_PWR_EnableBkUpAccess();
+#endif /* PWR_CR_DBP || PWR_CR1_DBP || PWR_DBPR_DBP */
+
 	LL_RTC_DisableWriteProtection(RTC);
 
 	MODIFY_REG(RTC->CALR, RTC_CALR_CALP | RTC_CALR_CALM, calp | calm);
 
 	LL_RTC_EnableWriteProtection(RTC);
 
+#if defined(PWR_CR_DBP) || defined(PWR_CR1_DBP) || defined(PWR_DBPCR_DBP) || defined(PWR_DBPR_DBP)
+	LL_PWR_DisableBkUpAccess();
+#endif /* PWR_CR_DBP || PWR_CR1_DBP || PWR_DBPR_DBP */
+
 	return 0;
 }