UDDF (SIPL) Drivers

When accessing Holoscan Sensor Bridge via SIPL, such as when using the SIPLCapture operator and/or running the sipl_player example application on a supported AGX Thor platform, the sensor drivers that are used are provided by external driver libraries written against the Unified Device Driver Framework (UDDF); these drivers are not provided by the HSB repo.

NVIDIA’s reference UDDF drivers are installed with JetPack as prebuilt binaries, and the source code for these drivers are also included with the SIPL Camera SDK package. For example, for the vb1940 reference driver included with JetPack 7.0:

• The prebuilt driver library is installed to /usr/lib/nvsipl_uddf/libnvuddf_eagle_library.so

• The source code for this library is available in /usr/src/jetson_sipl_api/sipl/uddf/samples/drivers/eagleAIO

Note that if the SIPL Camera SDK (and the above source code) is not installed, download and extract the Camera SIPL package from the JetPack Downloads page.

The sipl_player example application includes JSON config files (in examples/sipl_config/) that configure the application to use the installed UDDF driver libraries, and these will work out of the box with a new JetPack installation. See Leopard imaging VB1940 Eagle player example for an example of how to run this SIPL application using these configs and corresponding drivers.

If the reference UDDF drivers need to be updated – either to change the sensor programming or to update the Hololink code that is statically linked into the driver – the drivers can be recompiled and installed from the driver source code:

            

            
$ mkdir eagle_uddf && cd eagle_uddf
$ cmake /usr/src/jetson_sipl_api/sipl/uddf/samples/drivers/eagleAIO/
$ make -j
$ sudo make install
        

As noted above, these UDDF drivers interact with HSB using a statically linked copy of the Hololink core source code (see /usr/src/jetson_sipl_api/sipl/uddf/samples/drivers/eagleAIO/hololink/core). If the Hololink code of a UDDF driver needs to be updated, this can be done by overwriting the UDDF driver’s version of Hololink core with the latest in the HSB repo (e.g. from src/hololink/core) and then rebuilding/installing using the commands above.

Note that Hololink compatibility is only guaranteed with the Hololink tag corresponding to the JetPack release that is being used (i.e. JetPack_7.0); that is the version of the code as it was originally copied to the UDDF driver code. Newer versions of Hololink may not be compatible as-is and may require other updates to be made to the UDDF driver code.

As the HSB repo does not contain any UDDF drivers, adding new UDDF drivers is also not within the scope of this documentation. The Eagle VB1940 reference driver discussed and used above is meant to provide a sample UDDF driver implementation, and should be used as the basis for any new driver implementation.

It will be noted, however, that the HsbTransportDriver class included with the UDDF driver acts as the Hololink client for the UDDF driver, and is responsible for all interactions with HSB. Any updates to hololink::core within the driver may result in corresponding changes to HsbTransportDriver.

For more information on SIPL and how to write and use UDDF drivers, see the Camera Development using CoE section of the Jetson Linux Developer Guide.