From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Brownell Subject: Re: Re: USB storage problems on OHCI.. Date: Mon, 22 Sep 2003 09:22:22 -0700 Sender: linux-usb-devel-admin@lists.sourceforge.net Message-ID: <3F6F21BE.9090109@pacbell.net> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Errors-To: linux-usb-devel-admin@lists.sourceforge.net List-Help: List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: To: Linus Torvalds Cc: Alan Stern , Matthew Dharm , Greg KH , USB development list , SCSI development list List-Id: linux-scsi@vger.kernel.org Linus Torvalds wrote: > 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 _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel