Messages in this thread | | | Date | Fri, 27 Jan 2012 15:32:51 +0100 | From | Lars-Peter Clausen <> | Subject | How is dmaengine_prep_slave_single supposed to be used? |
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Hi,
I've tried using dmaengine_prep_slave_single in one of my drivers an run into an issue, the dma_address attribute of the sg element is not initialized and thus the dma transfer and the DMA transfer fails.
Quoting from Documentation/dmaengine.txt:
The peripheral driver is expected to have mapped the scatterlist for the DMA operation prior to calling device_prep_slave_sg, and must keep the scatterlist mapped until the DMA operation has completed.
So this is clearly not the case with dmaengine_prep_slave_single, so I'm wondering how is ut supposed to be used and can it work properly at all?
Thanks, - Lars
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