diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index cffd26f84..b016fc62c 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,8 @@
+2012-02-17  Corinna Vinschen  <corinna@vinschen.de>
+
+	* mount.cc (get_disk_type): Drop unneeded toupper call.  Convert case
+	constants to wide chars.
+
 2012-02-16  Corinna Vinschen  <corinna@vinschen.de>
 
 	* autoload.cc (NetUseGetInfo): Define.
diff --git a/winsup/cygwin/mount.cc b/winsup/cygwin/mount.cc
index 17d5c571f..90b369154 100644
--- a/winsup/cygwin/mount.cc
+++ b/winsup/cygwin/mount.cc
@@ -1851,25 +1851,25 @@ get_disk_type (LPCWSTR dos)
   if (is_dev (dev, L"\\Device\\"))
     {
       d += 8;
-      switch (toupper (*d))
+      switch (*d)
 	{
-	case 'C':
+	case L'C':
 	  if (is_dev (d, L"CdRom"))
 	    return DT_CDROM;
 	  break;
-	case 'F':
+	case L'F':
 	  if (is_dev (d, L"Floppy"))
 	    return DT_FLOPPY;
 	  break;
-	case 'H':
+	case L'H':
 	  if (is_dev (d, L"Harddisk"))
 	    return DT_HARDDISK;
 	  break;
-	case 'L':
+	case L'L':
 	  if (is_dev (d, L"LanmanRedirector\\"))
 	    return DT_SHARE_SMB;
 	  break;
-	case 'M':
+	case L'M':
 	  if (is_dev (d, L"MRxNfs\\"))
 	    return DT_SHARE_NFS;
 	  break;