diff --git a/include/linux/hw_random.h b/include/linux/hw_random.h
index 4f7d8f4b1e9ab098724370a8a6e8855ab9935c08..34a0dc18f3271ef01b14642c5117274c12fe18f1 100644
--- a/include/linux/hw_random.h
+++ b/include/linux/hw_random.h
@@ -29,7 +29,9 @@
  *			Returns the number of lower random bytes in "data".
  *			Must not be NULL.    *OBSOLETE*
  * @read:		New API. drivers can fill up to max bytes of data
- *			into the buffer. The buffer is aligned for any type.
+ *			into the buffer. The buffer is aligned for any type
+ *			and max is guaranteed to be >= to that alignment
+ *			(either 4 or 8 depending on architecture).
  * @priv:		Private data, for use by the RNG driver.
  * @quality:		Estimation of true entropy in RNG's bitstream
  *			(per mill).