On Fri, 31 Dec 2004, Benjamin Long wrote: > Greetings all! > > I've got a strange problem with my Dell 600m laptop. Along with the > laptop I got the D/Port Port replicator. The port replicator seems to > have a USB hub in it, which attaches to the EHCI bus. With the D/Port > attached Usbview shows this: (I hope the ascii graphics come though) > > |-UHCI Host Controller > |-UHCI Host Controller > |-UHCI Host Controller > --EHCI Host Controller > | > -hub > | > -USB Receiver (this is my wireless mouse) > > When I plug my Treo 90 into the D/Port's USB port, the visor module > shows up on the hub on the EHCI Host Controller. If I undock the laptop > and plug it into one of the ports on it, the visor module shows up on > one of the UHCI Host controller. As long as the visor module attaches to > a UHCI host, I have no problems with it. If it attaches to the EHCI one, > I cannot communicate with it. Dmesg shows this: > > usb 1-6.2: new full speed USB device using ehci_hcd and address 23 > visor 1-6.2:1.0: Handspring Visor / Palm OS converter detected > usb 1-6.2: Handspring Visor / Palm OS converter now attached to ttyUSB0 > usb 1-6.2: Handspring Visor / Palm OS converter now attached to ttyUSB1 > visor ttyUSB1: visor_open - failed submitting interrupt urb, error -28 > > When plugged into the laptop, I get this, with a working Treo: > > usb 3-1: new full speed USB device using uhci_hcd and address 3 > visor 3-1:1.0: Handspring Visor / Palm OS converter detected > usb 3-1: Handspring Visor / Palm OS converter now attached to ttyUSB0 > usb 3-1: Handspring Visor / Palm OS converter now attached to ttyUSB1 > > I'm running Fedora Core 3, with a custom built (from vanilla source) > 2.6.10 kernel. I'm hoping there is a fix for this because I cant get to > the ports on the laptop when the D/Port is attached. > > Any help would be greatly appreciated. > Thanks in advance.
This is a known shortcoming of the EHCI driver. Periodic transfers (like the interrupt urb referred to in the error message above) don't work properly when a full-speed device is attached to an external high-speed hub. Efforts are underway to improve the driver, but for now there's not much you can do about it directly. There is an indirect option, though: rmmod ehci_hcd. Without the EHCI driver loaded, all USB transfers will take place through the UHCI controller so the Treo will work. The downside is that if you then plug a high-speed device into the D/Port's hub, it will only operate at full-speed until you reload ehci_hcd. Alan Stern ------------------------------------------------------- The SF.Net email is sponsored by: Beat the post-holiday blues Get a FREE limited edition SourceForge.net t-shirt from ThinkGeek. It's fun and FREE -- well, almost....http://www.thinkgeek.com/sfshirt _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-users
