(Sorry for cross posting) Yesterday I had my new HP PSC-750 'all-in-one' printer/scanner/copier working after a fashion. I could print to it if I booted my server and the PSC750 in the 'right' order. (I don't really know the right order, but I was able to get everything running). This morning I embarked upon making 'hot-plugging' work because one of the issues I had with the printer is that the 'ptal-printd' process exits when the printer is turned off. Before getting into the particulars, my system is running a Redhat 6.2 distribution on a 2.2.20pre5 kernel. I did have to edit arch/i386/config.in to provide an option to enable CONFIG_HOTPLUG. I added: if [ "$CONFIG_KMOD" = "y" ]; then bool 'Support for hot-pluggable devices' CONFIG_HOTPLUG fi in the loadable modules area of the file. I have installed the latest usbutils RPM (version 0.8) and I installed the hotplug-2001_04_24-1 hot plug RPM. I also have the latest hpoj package from the CVS repository at sourceforge. Finally, I created the following script to start the OfficeJet daemons when the printer comes online (in /etc/hotplug/usb/printer): #!/bin/sh # Start the HP Office Jet Daemons /usr/local/bin/ptal-mlcd usb:0 -hotplug -device /dev/usb/lp0 /usr/local/bin/ptal-printd mlc:usb:0 -like /dev/lp0 & The hotplug logic does run /sbin/hotplug and this script does run, but I get I/O errors talking to the printer so ptal-mlcd exits: Jul 6 07:15:35 canopus kernel: usb.c: USB new device connect, assigned device number 2 Jul 6 07:15:35 canopus kernel: Manufacturer: Hewlett-Packard Jul 6 07:15:35 canopus kernel: Product: PSC 750 Jul 6 07:15:35 canopus kernel: SerialNumber: MY12DA10CRWB Jul 6 07:15:35 canopus kernel: printer.c: usblp0: USB Bidirectional printer dev 2 if 0 alt 0 Jul 6 07:15:35 canopus /sbin/hotplug: arguments (usb) env (ACTION=add DEVFS=/proc/bus/usb TERM=dumb DEVICE=/proc/bus/usb/001/002 HOSTTYPE=i386 PATH=/bin:/sbin:/usr/sbin:/usr/bin HOME=/ SHELL=/bin/bash DEBUG=yes INTERFACE=7/1/3 OSTYPE=Linux PRODUCT=3f0/1411/1.0 SHLVL=1 _=/usr/bin/env) Jul 6 07:15:35 canopus /sbin/hotplug: invoke /etc/hotplug/usb.agent () Jul 6 07:15:35 canopus /etc/hotplug/usb.agent: Modprobe and setup printer for USB product 3f0/1411/0100 Jul 6 07:15:35 canopus /etc/hotplug/usb.agent: Module setup printer for USB product 3f0/1411/0100 Jul 6 07:15:35 canopus ptal-mlcd: ptal-mlcd: SYSLOG at ExMgr.cpp:660, dev=, pid=1203, errno=111 ptal-mlcd successfully initialized. Jul 6 07:15:41 canopus kernel: usb_control/bulk_msg: timeout Jul 6 07:15:41 canopus ptal-mlcd: ptal-mlcd: ERROR at ExMgr.cpp:2940, dev=, pid=1203, errno=5 llioGetDeviceID: ioctl failed! Jul 6 07:15:41 canopus ptal-mlcd: ptal-mlcd: ERROR at ExMgr.cpp:2351, dev=, pid=1203, errno=25 llioOpenOne: llioGetDeviceID(/dev/usb/lp0) failed! Jul 6 07:15:42 canopus ptal-mlcd: ptal-mlcd: ERROR at ExMgr.cpp:2324, dev=, pid=1203, errno=25 Couldn't find device! Jul 6 07:15:42 canopus ptal-mlcd: ptal-mlcd: FATAL ERROR at ExMgr.cpp:757, dev=, pid=1203, errno=25 exActivate: Exiting due to activation failure. If I manually run ptal-mlcd and then attempt to run 'ptal-hp mlc:usb:0 display' then that also gets timeouts. (That was working yesterday). If it is any help, here is the output of 'dmesg' showing the timeout messages in the kernel: usb.c: kmalloc IF c11b0420, numif 1 usb.c: new device strings: Mfr=1, Product=2, SerialNumber=3 usb.c: USB device number 2 default language ID 0x409 Manufacturer: Hewlett-Packard Product: PSC 750 SerialNumber: MY12DA10CRWB printer.c: usblp0: USB Bidirectional printer dev 2 if 0 alt 0 usb.c: usblp driver claimed interface c11b0420 usb.c: kusbd: /sbin/hotplug add 2 usb.c: kusbd policy returned 0x0 usb_control/bulk_msg: timeout usb_control/bulk_msg: timeout Finally, the USB bus appears to be functional because 'lsusb' is working and it does show the HP printer. What can I do to debug this problem and get hotplugging and PTAL to work together correctly? Is there some magic switch for ptal-mlcd? -Ben McCann --- Ben McCann Enterasys Networks 31 Nagog Park Acton, MA, 01720 email: bmccann@enterasys.com web: www.enterasys.com phone: (978) 266-8140 fax: (978) 266-8111