killgxlin / virtual-display

USB/Ethernet Display driver sample for Windows

virtual-display

1. What is this?

   This sample code demonstrates how to make a USB or Ethernet display product by implementing a kernel driver that talks to LCI Proxy WDDM driver.

   LCI Proxy WDDM driver is a filter driver that talks to inbox display WDDM driver, and creates a virtual monitor on behalf of inbox display driver.

   The USB part of the driver receives the surface create/destroy/update messages from LCI Proxy WDDM driver. This sample code demonstrates the interaction between the source (LCI Proxy WDDM driver) and the target (eg. USB/Ethernet kernel driver) so that driver developers can make a USB/Ethernet display product easily.

2. Targe audience

   The sample code is targeted to USB/Ethernet display kernel driver developers. The sample code illustrates the internal driver communication between LCI Proxy WDDM driver and a target USB/Ethernet ethernet driver.

   The lci_display_internal_ioctl.h defines the internal IOCTL codes so that the target driver could get the virtual screen content efficiently.

   The ljb_vmon_ioctl.h is used by user mode sample app so that you can see the content of the virtual screen.

   The USB/Ethernet display developers can implement a real kernel device driver by leveraging the source code.

   The "notify" folder is derived from Microsoft toaster sample code, and is used merely fro demo purpose only. The user mode app is not intended to be used for real product scenario.

3. How to compile code.

   You need to install WDK10 as well WDK7. The user mode sample app is compiled with WDK7, while the kernel driver is compiled by WDK10.

   Use buildall_wdk10.cmd to build all components. An output folder is created as the result.

   There is also a precompiled driver binary under precompiled folder.

4. How to run the demo

   4.1 First, you need to install LCI Proxy WDDM driver. The LCI Proxy WDDM driver can be found in Fresco Logic FL2000 driver package. Goto https://support.frescologic.com/portal/home , and find the FL2000-2.1.xxxx.0 on the right hand side.

   4.2 Install the FL2000 driver even if you don't have FL2000 USB dongle. After installation, navigate to C:\Program Files\Fresco Logic\Fresco Logic USB Display Driver folder. Note that there is a devcon and lci_proxykmd folder. Copy out those 2 folders as you will need them later.

   4.3 Uninstall the FL2000 driver after step 4.2.

   4.4 Install lci_proxykmd by invoking cmd.exe with administrator privilege.

   Use the following command to install lci_proxykmd driver:
   
   "devcon\x64\devcon.exe install   lci_proxykmd\lci_proxykmd.inf  root\lci_proxykmd"
   
   You will see a "Fresco Logic Proxy Display Adapter" device node in the device manager view.
   
   You can also use "devcon\x64\devcon.exe status root\lci_proxykmd" to verify that it is correctly installed.
   
   Then you need to do "devcon\x64\devcon.exe restart =display"  to restart  display driver (such as Intel Graphics).
   

   4.5 Goto the output folder generated in step 3. In the cmd.exe window, navigate to the folder where "vmon_func.inf" exists.

   Use "devcon.exe install vmon_func.inf  root\ljb_vmon" to create a ljb_vmon device node.
   

   4.6 Invoke vmon.exe. You will see an extra monitor is created in device manager view. Also the vmon.exe displays the content on the virtual monitor just created.