4 files changed, 10 insertions, 0 deletions
diff --git a/os/hal/include/hal_st.h b/os/hal/include/hal_st.h
index 1cc0460c2..e285877d5 100644
--- a/os/hal/include/hal_st.h
+++ b/os/hal/include/hal_st.h
@@ -84,10 +84,12 @@
 extern "C" {
 #endif
   void stInit(void);
+#if OSAL_ST_MODE == OSAL_ST_MODE_FREERUNNING
   void stStartAlarm(systime_t abstime);
   void stStopAlarm(void);
   void stSetAlarm(systime_t abstime);
   systime_t stGetAlarm(void);
+#endif
 #ifdef __cplusplus
 }
 #endif
diff --git a/os/hal/ports/STM32/LLD/TIMv1/hal_st_lld.h b/os/hal/ports/STM32/LLD/TIMv1/hal_st_lld.h
index f1564c47d..156cd8902 100644
--- a/os/hal/ports/STM32/LLD/TIMv1/hal_st_lld.h
+++ b/os/hal/ports/STM32/LLD/TIMv1/hal_st_lld.h
@@ -89,6 +89,7 @@
 #define STM32_HAS_TIM22                     FALSE
 #endif
 
+#if OSAL_ST_MODE == OSAL_ST_MODE_FREERUNNING
 #if STM32_ST_USE_TIMER == 2
 #if !STM32_HAS_TIM2
 #error "TIM2 not present in the selected device"
@@ -158,6 +159,7 @@
 #else
 #error "STM32_ST_USE_TIMER specifies an unsupported timer"
 #endif
+#endif /* OSAL_ST_MODE == OSAL_ST_MODE_FREERUNNING */
 
 /*===========================================================================*/
 /* Driver data structures and types.                                         */
@@ -183,6 +185,7 @@ extern "C" {
 /* Driver inline functions.                                                  */
 /*===========================================================================*/
 
+#if (OSAL_ST_MODE == OSAL_ST_MODE_FREERUNNING) || defined(__DOXYGEN__)
 /**
  * @brief   Returns the time counter value.
  *
@@ -258,6 +261,7 @@ static inline bool st_lld_is_alarm_active(void) {
 
   return (bool)((STM32_ST_TIM->DIER & STM32_TIM_DIER_CC1IE) != 0);
 }
+#endif /* OSAL_ST_MODE == OSAL_ST_MODE_FREERUNNING */
 
 #endif /* HAL_ST_LLD_H */
 
diff --git a/os/hal/src/hal_st.c b/os/hal/src/hal_st.c
index 3c613c1b2..0143185f8 100644
--- a/os/hal/src/hal_st.c
+++ b/os/hal/src/hal_st.c
@@ -62,6 +62,7 @@ void stInit(void) {
   st_lld_init();
 }
 
+#if (OSAL_ST_MODE == OSAL_ST_MODE_FREERUNNING) || defined(__DOXYGEN__)
 /**
  * @brief   Starts the alarm.
  * @note    Makes sure that no spurious alarms are triggered after
@@ -123,6 +124,7 @@ systime_t stGetAlarm(void) {
 
   return st_lld_get_alarm();
 }
+#endif /* OSAL_ST_MODE == OSAL_ST_MODE_FREERUNNING */
 
 #endif /* OSAL_ST_MODE != OSAL_ST_MODE_NONE */
 
diff --git a/readme.txt b/readme.txt
index a12cfcaec..5fa860b95 100644
--- a/readme.txt
+++ b/readme.txt
@@ -198,6 +198,8 @@
 - EX:  Updated LIS302DL to 1.1.0 (backported to 18.2.1).
 - EX:  Updated LPS25H to 1.1.0 (backported to 18.2.1).
 - EX:  Updated LSM303DLHC to 1.1.0 (backported to 18.2.1).
+- HAL: Fixed STM32 ST driver problem in free running mode (bug #997)
+       (backported to 18.2.3 and 17.6.5).
 - HAL: Fixed invalid checks in STM32H7 HAL (bug #1000)
        (backported to 18.2.2).
 - OTH: Fixed problem in STM32H743 GCC linker file (bug #998)