On Fri, 8 Feb 2019 16:30:38 +0100 Federico Vaga <federico.vaga@xxxxxxx> wrote: > It clarifies that the DMA description pointer returned by > `dmaengine_prep_*` function should not be used after submission. > > Signed-off-by: Federico Vaga <federico.vaga@xxxxxxx> > --- > Documentation/driver-api/dmaengine/client.rst | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/Documentation/driver-api/dmaengine/client.rst b/Documentation/driver-api/dmaengine/client.rst > index fbbb2831f29f..d728e50105eb 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. > + Consequentially, 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 Applied to the docs tree, thanks. jon
