drivers: display: stm32_ltdc: mask irq if necessary

LTDC interrupt routine is used to reload frame buffer pointer
once full frame is finished flushing. As long as there is no
need to change buffer - there is no need to disturb CPU.
Thus: Enable LTDC interrupt only when new buffer is pending

Signed-off-by: Pavlo Hamov <[email protected]>

Author: pavlohamov

drivers/display/display_stm32_ltdc.c

@@ -223,8 +223,13 @@ static int stm32_ltdc_write(const struct device *dev, const uint16_t x,
 
 	data->pend_buf = pend_buf;
 
+	__HAL_LTDC_CLEAR_FLAG(&data->hltdc, LTDC_FLAG_LI);
+	__HAL_LTDC_ENABLE_IT(&data->hltdc, LTDC_IT_LI);
+
 	k_sem_take(&data->sem, K_FOREVER);
 
+	__HAL_LTDC_DISABLE_IT(&data->hltdc, LTDC_IT_LI);
+
 	return 0;
 }
 
@@ -479,7 +484,6 @@ static int stm32_ltdc_init(const struct device *dev)
 	LTDC->LIPCR = 0U;
 
 	__HAL_LTDC_CLEAR_FLAG(&data->hltdc, LTDC_FLAG_LI);
-	__HAL_LTDC_ENABLE_IT(&data->hltdc, LTDC_IT_LI);
 
 	return 0;
 }