On Mon, 8 Aug 2011, Adam Baker wrote: > Further testing reveals the situation is more complex than I first thought - > the behaviour I get depends upon whether what gets plugged in is a full speed > or a high speed device. After I've run the test of running gphoto whilst > streaming from a supported dual mode camera, lsusb fails to recognise a high > speed device plugged into the port the camera was plugged into (it works fine > if plugged in elsewhere) and lsusb hangs if I plug in a new low speed or full > speed device. When I get some time I'll see if I can recreate the problem > using libusb with a totally different device. Looking around my pile of USB > bits for something full speed with a kernel driver I've got a PL2303 serial > port. Would that be a good choice to test with? I have no idea. But the symptoms you describe are indicative of a hardware problem, not a driver bug. > Just for reference with a full speed device I see the messages below in dmesg > with the second one only appearing when I do lsusb > [10832.128039] usb 3-2: new full speed USB device using uhci_hcd and address > 34 > [10847.240031] usb 3-2: device descriptor read/64, error -110 > > and with a high speed device I see a continuous stream of > [11079.820097] usb 1-4: new high speed USB device using ehci_hcd and address > 103 > [11079.888355] hub 1-0:1.0: unable to enumerate USB device on port 4 > [11080.072377] hub 1-0:1.0: unable to enumerate USB device on port 4 > [11080.312053] usb 1-4: new high speed USB device using ehci_hcd and address > 105 > [11080.380418] hub 1-0:1.0: unable to enumerate USB device on port 4 > [11080.620030] usb 1-4: new high speed USB device using ehci_hcd and address > 106 > [11080.688322] hub 1-0:1.0: unable to enumerate USB device on port 4 The dmesg log is relatively uninformative unless you enable CONFIG_USB_DEBUG in the kernel build. Have you tried running these tests on a different computer, preferably one using a different chipset? Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
