diff --git a/include/linux/firewire-cdev.h b/include/linux/firewire-cdev.h
index 1f716d9f714b05b00d949891fd0b550e48fbee36..520ecf86cbb37b00bc7ec893bac4843b452fdeed 100644
--- a/include/linux/firewire-cdev.h
+++ b/include/linux/firewire-cdev.h
@@ -380,7 +380,7 @@ struct fw_cdev_initiate_bus_reset {
  * @immediate:	If non-zero, immediate key to insert before pointer
  * @key:	Upper 8 bits of root directory pointer
  * @data:	Userspace pointer to contents of descriptor block
- * @length:	Length of descriptor block data, in bytes
+ * @length:	Length of descriptor block data, in quadlets
  * @handle:	Handle to the descriptor, written by the kernel
  *
  * Add a descriptor block and optionally a preceding immediate key to the local
@@ -394,6 +394,8 @@ struct fw_cdev_initiate_bus_reset {
  * If not 0, the @immediate field specifies an immediate key which will be
  * inserted before the root directory pointer.
  *
+ * @immediate, @key, and @data array elements are CPU-endian quadlets.
+ *
  * If successful, the kernel adds the descriptor and writes back a handle to the
  * kernel-side object to be used for later removal of the descriptor block and
  * immediate key.