Why "lsusb" return nothing?

[Peter Teoh]

Furthermore, if u look at the /sys/bus/usb interface:

.
./uevent
./devices
./devices/usb1
./devices/1-0:1.0
./devices/usb2
./devices/2-0:1.0
./devices/1-1
./devices/1-1:1.0
./devices/2-1
./devices/2-1:1.0
./devices/1-1.1
./devices/1-1.1:1.0
./devices/1-1.2
./devices/1-1.2:1.0
./devices/1-1.3
./devices/1-1.3:1.0
./devices/1-1.4
./devices/1-1.4:1.0
./devices/1-1.5
./devices/1-1.5:1.0
./devices/1-1.5:1.1
./devices/2-1.2
./devices/2-1.2:1.0
./devices/2-1.3
./devices/2-1.3:1.0
./devices/2-1.6
./devices/2-1.6:1.0
./drivers
./drivers/usbfs
./drivers/usbfs/module
./drivers/usbfs/uevent
./drivers/usbfs/unbind
./drivers/usbfs/bind
./drivers/usbfs/new_id
./drivers/usbfs/remove_id
./drivers/usbfs/1-1.3:1.0
./drivers/hub
./drivers/hub/module
./drivers/hub/uevent
./drivers/hub/unbind
./drivers/hub/bind
./drivers/hub/new_id
./drivers/hub/remove_id
./drivers/hub/1-0:1.0
./drivers/hub/2-0:1.0
./drivers/hub/1-1:1.0
./drivers/hub/2-1:1.0
./drivers/usb
./drivers/usb/uevent
./drivers/usb/unbind
./drivers/usb/bind
./drivers/usb/usb1
./drivers/usb/usb2
./drivers/usb/1-1
./drivers/usb/2-1
./drivers/usb/1-1.1
./drivers/usb/1-1.2
./drivers/usb/1-1.3
./drivers/usb/1-1.4
./drivers/usb/1-1.5
./drivers/usb/2-1.2
./drivers/usb/2-1.3
./drivers/usb/2-1.6
./drivers/usb-storage
./drivers/usb-storage/1-1.1:1.0
./drivers/usb-storage/module
./drivers/usb-storage/uevent
./drivers/usb-storage/unbind
./drivers/usb-storage/bind
./drivers/usb-storage/remove_id
./drivers/usb-storage/2-1.2:1.0
./drivers/usbhid
./drivers/usbhid/1-1.2:1.0
./drivers/usbhid/module
./drivers/usbhid/uevent
./drivers/usbhid/unbind
./drivers/usbhid/bind
./drivers/usbhid/new_id
./drivers/usbhid/remove_id
./drivers/uvcvideo
./drivers/uvcvideo/1-1.5:1.0
./drivers/uvcvideo/1-1.5:1.1
./drivers/uvcvideo/module
./drivers/uvcvideo/uevent
./drivers/uvcvideo/unbind
./drivers/uvcvideo/bind
./drivers/uvcvideo/new_id
./drivers/uvcvideo/remove_id
./drivers_probe
./drivers_autoprobe

this I guessed account for some of the hardware (like USB mass storage
device) still working, whereas those that depend on the /dev/bus/usb
interface is not working (eg, Android's adb)

another symptom is that when i "mkdir -p /dev/bus/usb" directory, by
inserting a new USB harddisk, the directory is immediately deleted.
and now i can access the newly inserted harddisk, and dmesg returns:

[26949.222877] sd 12:0:0:0: [sdc] Mode Sense: 38 00 00 00
[26949.225095] sd 12:0:0:0: [sdc] No Caching mode page present
[26949.225099] sd 12:0:0:0: [sdc] Assuming drive cache: write through
[26949.230715] sd 12:0:0:0: [sdc] No Caching mode page present
[26949.230719] sd 12:0:0:0: [sdc] Assuming drive cache: write through
[26949.282965]  sdc: sdc1 sdc2 sdc4
[26949.288972] sd 12:0:0:0: [sdc] No Caching mode page present
[26949.288977] sd 12:0:0:0: [sdc] Assuming drive cache: write through
[26949.288980] sd 12:0:0:0: [sdc] Attached SCSI disk

seemingly noproblem - but "lsusb" returned NOTHING.

In fact I had also mirror the entire system into another different
hardware - before the /dev/bus/usb non-availability happened, and this
same system is still working fine.

So I am quite sure it is a udev thing, just trying my luck if anyone
know the answer?

On Sat, Sep 29, 2012 at 9:42 AM, Peter Teoh <htmldeveloper at gmail.com> 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



-- 
Regards,
Peter Teoh