diff --git a/include/linux/uio_driver.h b/include/linux/uio_driver.h
index 665517c..fd99ff9 100644
--- a/include/linux/uio_driver.h
+++ b/include/linux/uio_driver.h
@@ -23,7 +23,10 @@
 /**
  * struct uio_mem - description of a UIO memory region
  * @name:		name of the memory region for identification
- * @addr:		address of the device's memory
+ * @addr:		address of the device's memory (phys_addr is used since
+ * 			addr can be logical, virtual, or physical & phys_addr_t
+ * 			should always be large enough to handle any of the
+ * 			address types)
  * @size:		size of IO
  * @memtype:		type of memory addr points to
  * @internal_addr:	ioremap-ped version of addr, for driver internal use
@@ -31,7 +34,7 @@
  */
 struct uio_mem {
 	const char		*name;
-	unsigned long		addr;
+	phys_addr_t		addr;
 	unsigned long		size;
 	int			memtype;
 	void __iomem		*internal_addr;