diff --git a/components/bootloader_support/include/esp_image_format.h b/components/bootloader_support/include/esp_image_format.h
index c427cffa4..98e7bf238 100644
--- a/components/bootloader_support/include/esp_image_format.h
+++ b/components/bootloader_support/include/esp_image_format.h
@@ -37,7 +37,7 @@ typedef enum {
 } esp_image_spi_mode_t;
 
 /* SPI flash clock frequency */
-enum {
+typedef enum {
     ESP_IMAGE_SPI_SPEED_40M,
     ESP_IMAGE_SPI_SPEED_26M,
     ESP_IMAGE_SPI_SPEED_20M,