Re: Why "lsusb" return nothing?

[Mark Bishop <mark@xxxxxxxx>]

What does 'find /dev/ | grep dev' show

Peter Teoh <htmldeveloper@xxxxxxxxx> wrote:

what are the implication (or symptoms) of that statement?   how do i know that?

ps -ef |grep usb
root       232     2  0 07:44 ?        00:00:18 [usb-storage]
root       266     2  0 07:44 ?        00:00:14 [usb-storage]
root      6757     2  0 13:05 ?        00:00:00 [usb-storage]
root      6831  5920  0 13:05 pts/0    00:00:00 grep --color=auto usb

lsmod |grep usb
usbhid                 39214  0
hid                    89444  1 usbhid
usb_storage            49986  4

right now, i have no problem in accessing any USB devices.   when i
mirror the internal partition into an external USB storage disk, the
external USB storage partition successfully the exact identical OS -
with exactly the same sympton:   "lsusb" returning nothing.

it used to be working, and there is completely no change in the kernel
or module, as far as i am aware.   and "working" means "lsusb" used to
return everything.

On Sat, Sep 29, 2012 at 10:21 AM, Mark Bishop <mark@xxxxxxxx> wrote:
You don't have the USB module loaded or it isn't compiled into your kernel.

Peter Teoh <htmldeveloper@xxxxxxxxx> wrote:

I entered "lsusb" at the command line (as root) and nothing is return,
not even any error message.

Doing a strace the last few lines are:

open("/dev/bus/usb", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1
ENOENT (No such file or directory)
open("/proc/bus/usb", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1
ENOENT (No such file or directory)

What happened?

This is Ubuntu 10.04 (it used NOT to be like that, not sure I what did
wrong last time).   But running a VirtualBox INSIDE this same OS, I
was able to get result from "lsusb" (after enabling the USB devices in
VirtualBox interface) and strace gives result:

open("/dev/bus/usb/001/002", O_RDWR)    = 3
ioctl(3, USBDEVFS_IOCTL, 0xbff6f75c)    = -1 ENOTTY (Inappropriate
ioctl for device)
close(3)                                = 0
open("/dev/bus/usb/001/001", O_RDWR)    = 3

Why the difference?

--
Regards,
Peter Teoh



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