Re: MAX_USBFS_BUFFER_SIZE

From: René Rebe
Date: Wed Mar 01 2006 - 16:40:12 EST


Hi,

On Wednesday 01 March 2006 22:32, Greg KH wrote:
> On Wed, Mar 01, 2006 at 09:16:25PM +0100, Ren?? Rebe wrote:
> > Hi,
> >
> > I wonder if:
> >
> > drivers/usb/core/devio.c:86
> > #define MAX_USBFS_BUFFER_SIZE 16384
> >
> > is some random, or outdated limit or if there really is some code path that could
> > not handle bigger URBs.
> >
> > For performance reasons I would like to use bigger packages for an image
> > aquisition device.
>
> Why not just send down 2 urbs with that size then, that would keep the
> pipe quite full.

Because that requires even more modifications to libusb and sane (i_usb) ...

So, queing alot URBs is the recommended way to sustain the bus? Allowing
way bigger buffers will not be realistic?

Yours,


--
René Rebe - Rubensstr. 64 - 12157 Berlin (Europe / Germany)
http://www.exactcode.de | http://www.t2-project.org
+49 (0)30 255 897 45
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