3 files changed, 5 insertions, 1 deletions
diff --git a/os/hal/ports/STM32/LLD/TIMv1/gpt_lld.c b/os/hal/ports/STM32/LLD/TIMv1/gpt_lld.c
index 2852f383a..75c19f6b2 100644
--- a/os/hal/ports/STM32/LLD/TIMv1/gpt_lld.c
+++ b/os/hal/ports/STM32/LLD/TIMv1/gpt_lld.c
@@ -716,7 +716,8 @@ void gpt_lld_start_timer(GPTDriver *gptp, gptcnt_t interval) {
      SR bit 0 goes to 1. This is because the clearing of CNT has been inserted
      before the clearing of SR, to give it some time.*/
   gptp->tim->SR    = 0;                         /* Clear pending IRQs.      */
-  gptp->tim->DIER |= STM32_TIM_DIER_UIE;        /* Update Event IRQ enabled.*/
+  if (NULL != gptp->config->callback)
+    gptp->tim->DIER |= STM32_TIM_DIER_UIE;      /* Update Event IRQ enabled.*/
   gptp->tim->CR1   = STM32_TIM_CR1_URS | STM32_TIM_CR1_CEN;
 }
 
diff --git a/os/hal/ports/STM32/LLD/TIMv1/gpt_lld.h b/os/hal/ports/STM32/LLD/TIMv1/gpt_lld.h
index 9f0b16980..7146a9c3c 100644
--- a/os/hal/ports/STM32/LLD/TIMv1/gpt_lld.h
+++ b/os/hal/ports/STM32/LLD/TIMv1/gpt_lld.h
@@ -383,6 +383,8 @@ typedef struct {
   /**
    * @brief   Timer callback pointer.
    * @note    This callback is invoked on GPT counter events.
+   * @note    This callback can be set to @p NULL but in that case the
+   *          one-shot mode cannot be used.
    */
   gptcallback_t             callback;
   /* End of the mandatory fields.*/
diff --git a/os/hal/src/gpt.c b/os/hal/src/gpt.c
index d654a3c4a..52bf6610f 100644
--- a/os/hal/src/gpt.c
+++ b/os/hal/src/gpt.c
@@ -198,6 +198,7 @@ void gptStartOneShotI(GPTDriver *gptp, gptcnt_t interval) {
 
   osalDbgCheckClassI();
   osalDbgCheck(gptp != NULL);
+  osalDbgCheck(gptp->config->callback != NULL);
   osalDbgAssert(gptp->state == GPT_READY,
                 "invalid state");