Re: [alsa-devel] USB transfer_buffer allocations on 64bit systems

[Daniel Mack]

On Tue, May 11, 2010 at 10:57:07AM -0400, Alan Stern wrote:
> There are no calls to any dma_sync_* routines.  Daniel will have to
> check me on this, but I believe that urb->transfer_buffer is filled
> before dma_map_single() is called and it isn't touched again until
> after dma_unmap_single() (which occurs before urb's completion handler
> is called).

Yes, that's correct. Sorry fot the misleading information I gave. The
code doesn't to any weird tricks as it currently stands. It fills the
buffer, submits the URB and doesn't touch the buffer contents
afterwards.

Daniel

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