diff --git a/code/application/source/sf_app/code/source/app/sf_service.c b/code/application/source/sf_app/code/source/app/sf_service.c
index db156002f..474361c07 100755
--- a/code/application/source/sf_app/code/source/app/sf_service.c
+++ b/code/application/source/sf_app/code/source/app/sf_service.c
@@ -112,9 +112,7 @@ SINT32 app_ttyusb_IsOpen(void) {
             (retryTime % 100 == 0)) // 200ms*100 = 20s
         {
             MLOGE("-------ttyUSB init fail, clos usb mux.\n");
-            sf_usb_mux_s(0);
-            sleep(5);
-            sf_usb_mux_s(1);
+            sf_ttyusb_restart();
             retryFlag = 1;
         } else if ((1 == retryFlag) && (retryTime >= 50) &&
                     (retryTime % 50 == 0)) // 200ms*25 = 5s
@@ -888,7 +886,7 @@ SINT16 sf_thumb_file_creat(void) {
   	 free(strg_path);
 	 return SF_FAILURE;
   }
-  char *dcf_file = sf_get_strg_dev() == MMC_DEV_EMMC ? "SYBX" : "SYEX";
+  char *dcf_file = sf_get_strg_dev() == MMC_DEV_EMMC ? SF_EMMC_DCF_FILE_NAME : SF_SD_DCF_FILE_NAME;
   SF_SRCFILE_ATTR_S *fileCfg = sf_file_thumb_cfg_get();
 
   for (fileIndex = 0; fileIndex < fileCfg->filecnt; fileIndex++) {