On Wed, Dec 02, 2015 at 06:00:21PM +0100, Krzysztof Opasiak wrote: > > > On 12/02/2015 01:29 PM, Rogan Dawes wrote: > >As mentioned originally, I'm trying to come up with an IP KVM, as inexpensively as possible. Realising that the approach that I am following will not allow me to interact with any layers prior to a successfully booted operating system, what I am hoping to do is, at a minimum, be able to observe the DisplayLink traffic flowing from an external computer (i.e. not a VM) over the USB. > > > > If I understood your idea correctly you would like to do something > like rdp over USB, am I right? > > If yes then I'm currently running a project with students from > Warsaw University of Technology and they are doing exactly this:) > > What we would like to do: > - Use FunctionFS to emulate DisplayLink device > - Use f_hid to pass input events > - Maybe use f_ecm to share clipboard, file copy etc. > > Unfortunately currently we have only some very basic proof of > concept. We have ffs daemon and ConfigFS config to setup and act > like a display link with 640x480 monitor. So on a host side we see > another monitor and on the device side we have an window in which we > can see image from host. > > There are several problems. The most important one is display link > host driver and protocol documentation. We have implemented our > function based on open source display link driver (udl). > Unfortunately the performance is very poor 1280x1024 is absolutely > max what we can get if we don't want to have a slide show. udl > driver itself has also some problems and NULL ptr dereferences. > Moreover, Linux driver implements only very limited set of encodings > while Windows driver has much more of them and it's very easy to see > when you compare usb bandwidth used by widnows and linux driver. > > That's why we will try to improve udl driver. Currently we try to > setup machine at university which will run linux and then windows in > virtual machine. We would like to connect dl to this computer, pass > it to virtual machine and then use usbmon + wireshark and try to > figure out new encodings used by windows driver and add them to udl > driver but probably it will take a lot of time... > > Best regards, Hi, Yes, this is exactly what I am trying to implement. To be honest, I'd be quite happy with a single frame per second, but it sounds like you are way ahead of where I am. Is there any chance in getting a look at your code? Rogan -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
