Messages in this thread | | | Date | Tue, 17 Jan 2012 14:37:10 +0530 | From | Viresh Kumar <> | Subject | Re: [PATCH 7/8] dmaengine/dw_dmac: Unmap all memory buffers after completion of slave transfers |
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On 1/17/2012 2:22 PM, Linus Walleij wrote: > Basically the driver using the dmaengine shall map/unmap buffers > used for slave transfers, not the driver. > > I usually map them before setting up a transfer and unmaps them > when egtting the callback from the DMA engine that the transfer is > complete. >
You implemented similar stuff in amba-pl08x :) .
if (!plchan->slave) pl08x_unmap_buffers(txd);
> Why do you want to do this?
This is because people can pass in flags which are DMA_COMPL_SKIP_SRC_UNMAP, etc.
If they are not passed, then DMA driver must do it for them.
Sorry if i am understanding the DMA logic incorrectly.
-- viresh
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