Messages in this thread | | | Date | Mon, 27 Nov 2006 10:03:02 -0500 (EST) | From | Alan Stern <> | Subject | Re: [linux-usb-devel] [USB] urb->number_of_packets = 256 ! |
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On Mon, 27 Nov 2006, Duncan Sands wrote:
> Hi Ilyes, you won't be able to allocate that much *contiguous* memory, > but you should be able to allocate enough non-contiguous memory (e.g. > by calling __get_free_page 256 times; not the same as calling > __get_free_pages(8) !). To use that memory, you can try using the usb > scatter/gather support (see usb.h); I don't know if it works with > isochronous urbs though. I've CC'd the usb development list - maybe > someone there can help.
The scatter/gather library does not support iso.
> > Splitting the transfer across multiple URB doesn't seem to work (I didn't really > > investigate in depth this possibility).
It should work. Go back and try it again more carefully.
Alan Stern
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