invalid address returned by usb_alloc_coherent on dockstar

[MacLaren, James M]

>> That's where it's going wrong.  Buffers allocated by dma_alloc_coherent()
>> are already DMA coherent and must not be passed to dma_map_single().  I
>> believe USB has some way to be told that the buffer is already suitable
>> for DMA without needing additional handling.

>Yes,
>setting
>urb->transfer_flags  = URB_NO_TRANSFER_DMA_MAP
>will do this

>Regards,

>Martin


Russell and Martin

THANKS!!! That solved it.  I also saw in the linux device drivers 3rd edition that they added 

urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

after the call to usb_fill_bulk_urb

I did this and now it captures from /dev/video0 just fine.

If you ever find yourself in New Orleans I'll buy you a beer!

Thanks,
James
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