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-rw-r--r--Documentation/driver-api/dmaengine/client.rst7
-rw-r--r--Documentation/driver-api/dmaengine/dmatest.rst1
2 files changed, 8 insertions, 0 deletions
diff --git a/Documentation/driver-api/dmaengine/client.rst b/Documentation/driver-api/dmaengine/client.rst
index fbbb2831f29f..45953f171500 100644
--- a/Documentation/driver-api/dmaengine/client.rst
+++ b/Documentation/driver-api/dmaengine/client.rst
@@ -168,6 +168,13 @@ The details of these operations are:
dmaengine_submit() will not start the DMA operation, it merely adds
it to the pending queue. For this, see step 5, dma_async_issue_pending.
+ .. note::
+
+ After calling ``dmaengine_submit()`` the submitted transfer descriptor
+ (``struct dma_async_tx_descriptor``) belongs to the DMA engine.
+ Consequently, the client must consider invalid the pointer to that
+ descriptor.
+
5. Issue pending DMA requests and wait for callback notification
The transactions in the pending queue can be activated by calling the
diff --git a/Documentation/driver-api/dmaengine/dmatest.rst b/Documentation/driver-api/dmaengine/dmatest.rst
index 8d81f1a7169b..e78d070bb468 100644
--- a/Documentation/driver-api/dmaengine/dmatest.rst
+++ b/Documentation/driver-api/dmaengine/dmatest.rst
@@ -59,6 +59,7 @@ parameter, that specific channel is requested using the dmaengine and a thread
is created with the existing parameters. This thread is set as pending
and will be executed once run is set to 1. Any parameters set after the thread
is created are not applied.
+
.. hint::
available channel list could be extracted by running the following command::