Hi Luca,

On Mon, May 5, 2014 at 5:06 AM, Luca Ellero <lroluk@gmail.com> wrote:
>
> Hi all,
> can someone please tell me if it is legal to develop an USB driver
> analysing the USB protocol with a USB sniffer?
> Can this driver be made public under GPL?

Just though I'd point out that WireShark http://www.wireshark.org/ already has usb sniffing builtin http://wiki.wireshark.org/CaptureSetup/USB It uses the usbmon which is already part of the kernel
https://www.kernel.org/doc/Documentation/usb/usbmon.txt

--
Dave Hylands
Shuswap, BC, Canada
http://www.davehylands.com