[sane-devel] snooping of USB within linux

[Stéphane VOLTZ]

Le Samedi 31 Décembre 2005 13:57, Henning Meier-Geinitz a écrit :
> Hi,
>
> On 2005-12-29 23:25, Stephen More wrote:
> > I thought I would try and write a backend for SANE. I have used UsbSnoop
> > on windows  to collect some of the URB Data.  What is the equivalent
> > program on linux to snoop USB to see what I am actually sending ? With
> > any luck the output of both should be the same.
>
> As far as I know, there is no such program. However, I also have never
> seen the need of one until now.
>
> What you can do to look at what's actually sent to and received from
> the scanner is to enable debugging: export SANE_DEBUG_SANEI_USB=255.
> If your backend uses sanei_usb functions, you'll get all the necessary
> information.
>
> If I remember correctly, there is a similar feature in the Linux kernel.
> Such low level debugging is usefull if you try to find hardware bugs
> like the toggle issues found in some USB chipsets.
>
> Bye,
>   Henning

	Hello,

	yes there is such a feature in linux kernel. You'll have to recompile your 
kernel with the following option (from kernel's configuration help):

CONFIG_USB_MON:

If you say Y here, a component which captures the USB traffic
between peripheral-specific drivers and HC drivers will be built. 
For more information, see <file:Documentation/usb/usbmon.txt>. 
 
This is somewhat experimental at this time, but it should be safe.

If unsure, say Y.
            
Symbol: USB_MON [=y] 
Prompt: USB Monitor
  Defined at drivers/usb/mon/Kconfig:5 
  Depends on: USB  
  Location:     
    -> Device Drivers 
      -> USB support 
        -> Support for Host-side USB (USB [=m]) 

Regards,
	Stef