-#define PCI_FILL_CAPS 0x0040
-#define PCI_FILL_EXT_CAPS 0x0080
-#define PCI_FILL_PHYS_SLOT 0x0100
-#define PCI_FILL_MODULE_ALIAS 0x0200
-#define PCI_FILL_LABEL 0x0400
+#define PCI_FILL_CAPS 0x0040 /* capabilities */
+#define PCI_FILL_EXT_CAPS 0x0080 /* extended capabilities */
+#define PCI_FILL_PHYS_SLOT 0x0100 /* physical slot (string property) */
+#define PCI_FILL_MODULE_ALIAS 0x0200 /* Linux kernel module alias (string property) */
+#define PCI_FILL_LABEL 0x0400 /* (string property) */