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    SubjectRe: Driver for Microsoft USB Fingerprint Reader
    On Mon, Jul 03, 2006 at 11:56:26PM -0400, Daniel Bonekeeper wrote:
    > Maybe this is not a default on the market and is something that is
    > coming... but seems that some USB controllers are coming with DMA
    > capabilities:
    >
    > http://www.usb.org/developers/presentations/pres0501/Augustin_DMA_Implem_Final.ppt
    > http://www.semiconductors.philips.com/pip/isp1183.html

    I think you are a bit confused. Of course the USB Host controller
    devices support DMA, that's how things are set up and work properly
    without using a ton of CPU. They are usually PCI devices and work quite
    well and use DMA.

    It's the USB devices themselves that don't and can't do any DMA
    themselves.

    Hope this helps explain things.

    greg k-h
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