diff --git a/Documentation/firmware_class/README b/Documentation/firmware_class/README
index c3480aa66ba8..7eceaff63f5f 100644
--- a/Documentation/firmware_class/README
+++ b/Documentation/firmware_class/README
@@ -77,7 +77,8 @@
    seconds for the whole load operation.
 
  - request_firmware_nowait() is also provided for convenience in
-   non-user contexts.
+   user contexts to request firmware asynchronously, but can't be called
+   in atomic contexts.
 
 
  about in-kernel persistence:
diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index 2d296b7f7034..242770250584 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -617,8 +617,9 @@ request_firmware_work_func(void *arg)
  * @cont: function will be called asynchronously when the firmware
  *	request is over.
  *
- *	Asynchronous variant of request_firmware() for contexts where
- *	it is not possible to sleep.
+ *	Asynchronous variant of request_firmware() for user contexts where
+ *	it is not possible to sleep for long time. It can't be called
+ *	in atomic contexts.
  **/
 int
 request_firmware_nowait(