On Wed, May 09, 2012 at 12:19:39PM -0400, Sergio Correia wrote: > On Wed, May 9, 2012 at 11:59 AM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > > On Wed, 9 May 2012, Sergio Correia wrote: > > > >> Hi Alan, Sarah, > >> > >> On Wed, May 9, 2012 at 10:33 AM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > >> > On Tue, 8 May 2012, Sarah Sharp wrote: > >> > > >> >> On Tue, May 08, 2012 at 03:26:17PM -0700, Sarah Sharp wrote: > >> >> > Yeah, it looks like the Fresco Logic host controller is reporting a > >> >> > successful completion status, with an untransferred length of 8 bytes, > >> >> > which is a contradiction. Since we can tell from the EHCI logs that it > >> >> > actually should be reporting a short packet status, I think we should be > >> >> > able to just add a quirk for it, to trust the untransferred length. > >> >> > > >> >> > I wonder if this is just for short control transfers, or if they have > >> >> > this bug for other endpoint types? > >> >> > >> >> Er, I meant "short isochronous transfers", not short control transfers. > >> > > >> > It should be easy enough to find out, by plugging in a USB drive. Most > >> > of them generate short bulk transfers during SCSI initialization. > >> > > >> > Alan Stern > >> > > >> > >> I have an external USB 2.0 disk and also a USB 2.0 drive handy. Shall > >> I try the 1st patch (short packet completion debugging) with them on > >> the USB 3.0 port to check if it reports something else strange? > > > > Go ahead. > > > > the dmesg outputs are there: > http://www.uece.net/misc/usb-headset-problem/dmesg-wd-2tb-disk-usb2.0 > http://www.uece.net/misc/usb-headset-problem/dmesg-kingston-8gb-drive-usb2.0 It looks like the Fresco Logic host controller is correctly reporting short transfers for bulk endpoints, just not isochronous endpoints. Alan, do you know which USB devices might have interrupt IN endpoints that are likely to send short packets? Sarah Sharp -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
