Re: [PATCH] usb bulk transfer: 1024 byte packets

[Pete Zaitcev]

On Sat, 14 Apr 2007 09:14:25 -0400 (EDT), "Jeremy C. Andrus" <jeremy@xxxxxxxxxxx> wrote:
> On Fri, April 13, 2007 22:16, Pete Zaitcev wrote:

> > The transfer size in the URB is not limited by the maximum packet
> > size. The HC driver splits up the transfer as specified by URB into
> > the required number of packets.
> 
> The problem was not in the transfer from PC -> Device, but from Device
> -> PC. If I remember correctly, the 512 limit (in the
> urb->transfer_flags) is used to setup the DMA. When the device sent
> packets which were 1024 bytes in size, the urb came back with a status
> set to -EOVERFLOW.

It's a bug in your driver. Supply the correct size with the URB and
all will be fine. Like I said, HC splits up the transfer transparently,
no matter what direction.

-- Pete
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