On Sun, 13 Nov 2005, Johannes Zweng wrote: > On Sun, 13 Nov 2005 11:10:19 -0500 (EST) > Alan Stern <[EMAIL PROTECTED]> wrote: > > > On Sun, 13 Nov 2005, Johannes Zweng wrote: > > > > > 1.) When I plug in the phone and it's using configuration 1 (AT > > > modem mode) "bNumConfigurations" reports 2 available > > > configurations, but AFTER SWITCHING to configuration 2 it only > > > reports one available configuration (via "bNumConfigurations"). > > > > What exactly do you mean: via "bNumConfigurations"? Do you mean that > > > > "lsusb -v" reports a different value? Does the value in > > /proc/bus/usb/devices change? What about the value in the sysfs > > file? (Those last two should _not_ be able to change unless the > > phone disconnects itself.) > > I checked the value in /sys/bus/usb/devices/4-2/bNumConfigurations > > And this value definitly changes to 1 after switching to configuartion > 2 by doing "echo 2 > /sys/bus/usb/devices/4-2/bConfigurationValue". > > So it's not possible to switch back to configuration 1 the same > way because the device claims to have only one configuration after the > change. > > > > > 2.) Also the device id of the device changes from "22b8:4902" to > > > "22b8:4902" when I change to configuration 2. > > > > Those two values are in fact the same. I'll assume you meant one of > > them to be different. > > > > Again, where do you determine these ID values? > > Yes, this was a typo, sorry. > The device id changes from 22b8:4902 to 22b8:4901. I determined this > values via sysfs in "idVendor" and "idProduct". But "lsusb -v" also > reports these values. > > > To give you an idea what happens during the configuration switch, here > an extract of udevmonitor's output while switching to configuration 2: > > UEVENT[1131897292] > remove@/devices/pci0000:00/0000:00:11.2/usb4/4-2/4-2:1.0 > UEVENT[1131897292] > remove@/devices/pci0000:00/0000:00:11.2/usb4/4-2/4-2:1.1 > UEVENT[1131897292] > remove@/devices/pci0000:00/0000:00:11.2/usb4/4-2 > > UEVENT[1131897295] > add@/devices/pci0000:00/0000:00:11.2/usb4/4-2 > UEVENT[1131897295] > add@/devices/pci0000:00/0000:00:11.2/usb4/4-2/4-2:1.5 > UEVENT[1131897295] > add@/devices/pci0000:00/0000:00:11.2/usb4/4-2/4-2:1.6 > UEVENT[1131897295] > add@/devices/pci0000:00/0000:00:11.2/usb4/4-2/4-2:1.8
Aha! So the phone _does_ disconnect itself and then reconnect. In between it changes its descriptors. In essence, the kernel thinks the phone has been unplugged and in its place is a completely new device, with only one configuration. To put the phone back into its original configuration, you might need to reset it, maybe even unplug the USB cable. A port reset might or might not be good enough. Or maybe all you have to do is set the configuration to 0 (which means unconfigured). Perhaps that will switch the phone back to its original setting, with both configs available. Alan Stern ------------------------------------------------------- SF.Net email is sponsored by: Tame your development challenges with Apache's Geronimo App Server. Download it for free - -and be entered to win a 42" plasma tv or your very own Sony(tm)PSP. Click here to play: http://sourceforge.net/geronimo.php _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
