video: stm32_dcmi: snapshot timeout

Find at times that the camera when started may for
some reason not return an image.  So added currently
hard coded 5 second timeout for a frame.  Should be
settable.  But at least it recovers and starts getting
pictures again.

Signed-off-by: Kurt Eckhardt <[email protected]>

Update video_stm32_dcmi.c

Author: KurtE

drivers/video/video_stm32_dcmi.c

@@ -45,6 +45,7 @@ struct video_stm32_dcmi_data {
 	struct k_fifo fifo_in;
 	struct k_fifo fifo_out;
 	struct video_buffer *vbuf;
+	uint32_t snapshot_start_time;
 	bool snapshot_mode;
 };
 
@@ -63,19 +64,19 @@ static void stm32_dcmi_process_dma_error(DCMI_HandleTypeDef *hdcmi)
 		CONTAINER_OF(hdcmi, struct video_stm32_dcmi_data, hdcmi);
 
 	LOG_WRN("Restart DMA after Error!");
-	/* Lets try to recover by stopping and maybe restart */
+
+	/* Lets try to recover by stopping and  restart */
 	if (HAL_DCMI_Stop(&dev_data->hdcmi) != HAL_OK) {
-	LOG_WRN("HAL_DCMI_Stop FAILED!");
+		LOG_WRN("HAL_DCMI_Stop FAILED!");
 		return;
 	}
 
-	/* error on last transfer try to restart it */
 	if (HAL_DCMI_Start_DMA(&dev_data->hdcmi,
-       			      dev_data->snapshot_mode ? DCMI_MODE_SNAPSHOT : DCMI_MODE_CONTINUOUS,
-			      (uint32_t)dev_data->vbuf->buffer,
-			      dev_data->vbuf->size / 4) != HAL_OK) {
-	       LOG_WRN("Continuous: HAL_DCMI_Start_DMA FAILED!");
-	       return;
+			       dev_data->snapshot_mode ? DCMI_MODE_SNAPSHOT : DCMI_MODE_CONTINUOUS,
+			       (uint32_t)dev_data->vbuf->buffer,
+			       dev_data->vbuf->size / 4) != HAL_OK) {
+		LOG_WRN("Continuous: HAL_DCMI_Start_DMA FAILED!");
+		return;
 	}
 }
 
@@ -327,6 +328,8 @@ static int video_stm32_dcmi_enqueue(const struct device *dev, struct video_buffe
 	return 0;
 }
 
+#define SNAPSHOT_TIMEOUT_MS 5000
+
 static int video_stm32_dcmi_dequeue(const struct device *dev, struct video_buffer **vbuf,
 				    k_timeout_t timeout)
 {
@@ -335,7 +338,29 @@ static int video_stm32_dcmi_dequeue(const struct device *dev, struct video_buffe
 	if (data->snapshot_mode) {
 		LOG_DBG("dequeue snapshot: %p %llu\n", data->vbuf, timeout.ticks);
 		/* See if we were already called and have an active buffer */
-		if (data->vbuf == NULL) {
+		if (data->vbuf != NULL) {
+			uint32_t time_since_start_time =
+				(uint32_t)(k_uptime_get_32() - data->snapshot_start_time);
+			if (time_since_start_time > SNAPSHOT_TIMEOUT_MS) {
+				LOG_WRN("Snapshot: Timed out!");
+				if (HAL_DCMI_Stop(&data->hdcmi) != HAL_OK) {
+					LOG_WRN("Snapshot: HAL_DCMI_Stop FAILED!");
+				}
+
+				if (HAL_DCMI_Start_DMA(&data->hdcmi, DCMI_MODE_SNAPSHOT,
+						       (uint32_t)data->vbuf->buffer,
+						       data->vbuf->size / 4) != HAL_OK) {
+					LOG_WRN("Snapshot: HAL_DCMI_Start_DMA FAILED!");
+					return -EIO;
+				}
+
+				/* remember when we started this request */
+				data->snapshot_start_time = k_uptime_get_32();
+			} else {
+				LOG_DBG("Snapshot: restart after timeout");
+			}
+
+		} else {
 			/* check first to see if we already have a buffer returned */
 			*vbuf = k_fifo_get(&data->fifo_out, K_NO_WAIT);
 			if (*vbuf != NULL) {
@@ -358,8 +383,9 @@ static int video_stm32_dcmi_dequeue(const struct device *dev, struct video_buffe
 				LOG_WRN("Snapshot: HAL_DCMI_Start_DMA FAILED!");
 				return -EIO;
 			}
-		} else {
-			LOG_DBG("Snapshot: restart after timeout");
+
+			/* remember when we started this request */
+			data->snapshot_start_time = k_uptime_get_32();
 		}
 	}