DEBUGGING USB SUBSYSTEM
-----------------------

0. Have HP LaserJet 1020

1. Install the latest http://foo2zjs.rkkda.com/foo2zjs.tar.gz

2. Prepare the kernel

    Taken from: /usr/src/linux/Documentation/usb/usbmon.txt
    https://www.kernel.org/doc/html/latest/usb/usbmon.html

    # mount -t debugfs none_debugs /sys/kernel/debug
    # modprobe usbmon				(if kernel loads a module)

    # ls /sys/kernel/debug/usbmon
    1s  1t  2s  2t  3s  3t  4s  4t

    # grep -B4 /proc/bus/usb/devices Laser
    T:  Bus=01 Lev=01 Prnt=01 Port=04 Cnt=01 Dev#=  3 Spd=480 MxCh= 0
    D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
    P:  Vendor=03f0 ProdID=2b17 Rev= 1.00
    S:  Manufacturer=Hewlett-Packard
    S:  Product=HP LaserJet 1020

    Bus=01 is what you fill it here,

3. Start 'cat'

    # BUS=1t
    # cat /sys/kernel/debug/usbmon/$BUS > /tmp/1.mon.out

4. Wait for problem.....

5. Interrupt 'cat' with Control-C

6. File bug report at:

    RedHat:	https://bugzilla.redhat.com/bugzilla/index.cgi
    Mandriva:	http://qa.mandriva.com/
    SUSE:	http://en.opensuse.org/Submitting_Bug_Reports
    Ubuntu:	https://launchpad.net/distros/ubuntu/+bugs

    Do not file bug report with me.  It is a kernel problem.
