diff --git a/drivers/mtd/ftl.c b/drivers/mtd/ftl.c
index f9350d85cf..2019e026e2 100644
--- a/drivers/mtd/ftl.c
+++ b/drivers/mtd/ftl.c
@@ -208,7 +208,7 @@ static ssize_t ftl_read(FAR struct inode *inode, unsigned char *buffer,
 {
   FAR struct ftl_struct_s *dev;
 
-  finfo("sector: %d nsectors: %d\n", start_sector, nsectors);
+  finfo("sector: %zu nsectors: %d\n", start_sector, nsectors);
 
   DEBUGASSERT(inode && inode->i_private);
 
@@ -442,7 +442,7 @@ static ssize_t ftl_write(FAR struct inode *inode,
 {
   struct ftl_struct_s *dev;
 
-  finfo("sector: %d nsectors: %d\n", start_sector, nsectors);
+  finfo("sector: %zu nsectors: %d\n", start_sector, nsectors);
 
   DEBUGASSERT(inode && inode->i_private);
   dev = (struct ftl_struct_s *)inode->i_private;
@@ -479,7 +479,7 @@ static int ftl_geometry(FAR struct inode *inode,
 
       finfo("available: true mediachanged: false writeenabled: %s\n",
             geometry->geo_writeenabled ? "true" : "false");
-      finfo("nsectors: %d sectorsize: %d\n",
+      finfo("nsectors: %zu sectorsize: %zu\n",
             geometry->geo_nsectors, geometry->geo_sectorsize);
 
       return OK;