1 files changed, 1 insertions, 1 deletions
diff --git a/MdePkg/Include/Protocol/DeviceIo.h b/MdePkg/Include/Protocol/DeviceIo.h
index fc68603b34..99a48cdccb 100644
--- a/MdePkg/Include/Protocol/DeviceIo.h
+++ b/MdePkg/Include/Protocol/DeviceIo.h
@@ -135,7 +135,7 @@ typedef enum {
   @param  Operation             Indicates if the bus master is going to read or write to system memory.
   @param  HostAddress           The system memory address to map to the device.
   @param  NumberOfBytes         On input, the number of bytes to map.
-                                On output the number of bytes that were mapped.
+                                On output, the number of bytes that were mapped.
   @param  DeviceAddress         The resulting map address for the bus master device to use to access the
                                 hosts HostAddress.
   @param  Mapping               A resulting value to pass to Unmap().