On Mon, 9 Feb 2009, peter gervai wrote: > Sorry, terminology problem. Pen and card reader was running HIGHSPEED (usb2.0, > which is the full speed of the device, which isn't "full speed" by USB talk), > corectly. Call it the maximum speed of the device, not the full speed of the device. > Hub does run at usb1.1, or "full speed", while it should be capable of "high > speed". > > > Conversely, if you plug the Genesys hub into other computers, does it > > then run at high speed? If not, then most likely the hub isn't working > > right. > > Well I do not have plenty of computers around (at least not with USB2.0 plugs, > as I have plenty of junk anyway), the one which possess USB2.0 but is a very > similar chipset, and it sees the hub "full speed" (usb1.1) as well. That's why > I asked about whether anyone met this chipset and whether it ran high speed > anywhere at all. So maybe the hub is simply broken. > > > Feb 7 15:52:33 narya kernel: [827442.494242] ehci_hcd 0000:00:1d.7: port > > > 4 full speed --> companion > > > > Here you see that the EHCI hardware on the computer thinks it has > > detected that the Genesys hub doesn't want to run at high speed. > > Yes but this one was weird to me: > > > > Feb 7 15:52:33 narya kernel: [827442.754023] usb 3-2: new full speed USB > > > device using uhci_hcd and address 11 > > > Feb 7 15:52:33 narya kernel: [827442.887546] usb 3-2: not running at top > > > speed; connect to a high speed hub > > ... > > So the hub states that it's a high-speed device, and the USB subsystem seems > to be aware of that fact. Yes. To be more precise, the hub has an "other-speed descriptor". Since it is running at full speed, the kernel realizes that the "other" speed must be high speed. Besides, all USB 2.0 hubs are required to be able to run at high speed. It's in the spec. > I'll try to talk to Genesys about this, since I'm > out of permutations available on my present hardware pool. > > It's pretty hard to claim faulty hardware usb-wise since it's a mistery to > hardware shops... they probably couldn't tell 1.1 from 2.0 even if forced by > firearms. You need to be more careful in your use of terms. 1.1 vs. 2.0 is not the same as full-speed vs. high-speed. There are USB-2.0 devices which cannot run at high speed; that's a perfectly valid combination (although it's not valid for hubs). Alan Stern -- 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
