On Mon, 22 Sep 2003, Alan Stern wrote:
This problem has been cropping up with many, many USB storage devices.
Interesting data-point: the device is a happy EHCI camper, and is totally able to read codepage 8 on EHCI.
However, if I put it behind a USB-1 hub on the EHCI port, I see the same problems I saw with OHCI.
Can you be more clear? Is that
(EHCI/OHCI) root port --> USB 2.0 hub --> USB 1.1 hub --> storage device
Or instead
(EHCI/OHCI) root port --> USB 1.1 hub --> storage device
The former is certainly using EHCI, and the transaction translator in that USB 2.0 hub ... but I'd expect it to give a different failure mode. Maybe the same net result, but a different fault code (not -EOVERFLOW), and likely different recovery procedure in usb-storage/scsi.
The latter is identical with the OHCI-only case, the only involvement of EHCI being to hand that port over to the (OHCI) companion.
So it is somehow related to USB-1 vs USB-2. I don't understand why the device would make a difference for something like mode page 8, but it looks like it transfers data fine for _small_ mode page requests under USB-1, and under USB-2 it works even for big ones.
It could be some kind of logic in the device forgetting that to use the right maxpacket setting in that specific case.
I'm a bit more used to seeing failures the other way around, where the storage adapter doesn't quite respond correctly at high speed.
- Dave
Linus
------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
