Merge tag 'cris-for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jesper...

[cascardo/linux.git] / Documentation / dmaengine / provider.txt

diff --git a/Documentation/dmaengine/provider.txt b/Documentation/dmaengine/provider.txt
index 91ce82d..c4fd475 100644 (file)
--- a/Documentation/dmaengine/provider.txt
+++ b/Documentation/dmaengine/provider.txt
@@ -282,6 +282,17 @@ supported.
                        that is supposed to push the current
                        transaction descriptor to a pending queue, waiting
                        for issue_pending to be called.
+     - In this structure the function pointer callback_result can be
+       initialized in order for the submitter to be notified that a
+       transaction has completed. In the earlier code the function pointer
+       callback has been used. However it does not provide any status to the
+       transaction and will be deprecated. The result structure defined as
+       dmaengine_result that is passed in to callback_result has two fields:
+       + result: This provides the transfer result defined by
+                dmaengine_tx_result. Either success or some error
+                condition.
+       + residue: Provides the residue bytes of the transfer for those that
+                 support residue.
 
    * device_issue_pending
      - Takes the first transaction descriptor in the pending queue,