diff --git a/src/calibre/devices/kindle/driver.py b/src/calibre/devices/kindle/driver.py
index 1770a793ec..35a73f86f0 100644
--- a/src/calibre/devices/kindle/driver.py
+++ b/src/calibre/devices/kindle/driver.py
@@ -388,13 +388,9 @@ class KINDLE_FIRE(KINDLE2):
 
     EBOOK_DIR_MAIN = 'Documents'
     SUPPORTS_SUB_DIRS = False
+    SCAN_FROM_ROOT = True
+    SUPPORTS_SUB_DIRS_FOR_SCAN = True
     VENDOR_NAME = 'AMAZON'
     WINDOWS_MAIN_MEM = 'KINDLE'
 
-    def get_main_ebook_dir(self, for_upload=False):
-        if for_upload:
-            return self.EBOOK_DIR_MAIN
-        return ''
-
-
 
diff --git a/src/calibre/devices/usbms/deviceconfig.py b/src/calibre/devices/usbms/deviceconfig.py
index 3f669f1e24..bc7dc116e2 100644
--- a/src/calibre/devices/usbms/deviceconfig.py
+++ b/src/calibre/devices/usbms/deviceconfig.py
@@ -28,6 +28,8 @@ class DeviceConfig(object):
     EXTRA_CUSTOMIZATION_DEFAULT = None
 
     SUPPORTS_SUB_DIRS = False
+    SUPPORTS_SUB_DIRS_FOR_SCAN = False # This setting is used when scanning for
+                                       # books when SUPPORTS_SUB_DIRS is False
     MUST_READ_METADATA = False
     SUPPORTS_USE_AUTHOR_SORT = False
 
diff --git a/src/calibre/devices/usbms/driver.py b/src/calibre/devices/usbms/driver.py
index e09876081b..ff2b6f3891 100644
--- a/src/calibre/devices/usbms/driver.py
+++ b/src/calibre/devices/usbms/driver.py
@@ -202,7 +202,7 @@ class USBMS(CLI, Device):
             debug_print('USBMS: scan from root', self.SCAN_FROM_ROOT, ebook_dir)
             if not os.path.exists(ebook_dir): continue
             # Get all books in the ebook_dir directory
-            if self.SUPPORTS_SUB_DIRS:
+            if self.SUPPORTS_SUB_DIRS or self.SUPPORTS_SUB_DIRS_FOR_SCAN:
                 # build a list of files to check, so we can accurately report progress
                 flist = []
                 for path, dirs, files in os.walk(ebook_dir):