Add comment for device path protocol.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@6175 6f19259b-4bc3-4df7-8a09-765794883524

diff --git a/MdePkg/Include/Protocol/DevicePath.h b/MdePkg/Include/Protocol/DevicePath.h
index 1286372f03a6aea8592081fb8887185806ede742..2103452909b21e9a96fc8d24f20f3df05b8b5310 100644 (file)
--- a/MdePkg/Include/Protocol/DevicePath.h
+++ b/MdePkg/Include/Protocol/DevicePath.h
@@ -40,10 +40,30 @@
 \r
 #pragma pack(1)\r
 \r
+/**\r
+  This protocol can be used on any device handle to obtain generic path/location \r
+  information concerning the physical device or logical device. If the handle does \r
+  not logically map to a physical device, the handle may not necessarily support \r
+  the device path protocol. The device path describes the location of the device \r
+  the handle is for. The size of the Device Path can be determined from the structures \r
+  that make up the Device Path.\r
+**/\r
 typedef struct {\r
-  UINT8 Type;\r
-  UINT8 SubType;\r
-  UINT8 Length[2];\r
+  UINT8 Type;       ///< 0x01 - Hardware Device Path\r
+                    ///< 0x02 – ACPI Device Path\r
+                    ///< 0x03 – Messaging Device Path\r
+                    ///< 0x04 – Media Device Path\r
+                    ///< 0x05 – BIOS Boot Specification Device Path\r
+                    ///< 0x7F – End of Hardware Device Path\r
+                    \r
+  UINT8 SubType;    ///< Varies by Type\r
+                    ///< 0xFF – End Entire Device Path, or\r
+                    ///< 0x01 – End This Instance of a Device Path and start a new\r
+                    ///< Device Path\r
+                    \r
+  UINT8 Length[2];  ///< Specific Device Path data. Type and Sub-Type define\r
+                    ///< type of data. Size of data is included in Length.\r
+                    \r
 } EFI_DEVICE_PATH_PROTOCOL;\r
 \r
 ///\r