VSS add-on coordination (mapping)

[erikbosch]

This is a topic originating from the Porto AMM

There are multiple initiatives using VSS syntax to add extended attributes. Two examples are KUKSA.val (map DBC to VSS) and COVESA AASIG (map Android VHAL to/from VSS). There is a possibility that a platform/project need to use multiple mappings, and then it is important that there are no name conflicts.

COVESA could address this by:

• Providing guidelines, for example that all attributes are to be added under a single "namespace"
• Maintain a list of already taken/used "namespaces".
• Possibly "host" some "namespace" definitions, i.e. the definition of sub-attributes and syntax for them

With this, inspired by the two examples below, it would be possible to include multiple mappings in the same tree (after applying overlays), like:

Vehicle.Chassis.SteeringWheel.Angle:
  datatype: int16
  type: sensor
  dbc:
    signal: SteeringAngle129
    interval_ms: 100
    transform:
      math: "floor(x+0.5)"
  vhal:
    aospId: VehicleProperty::PERF_VEHICLE_SPEED
    aospArea: VehicleArea::GLOBAL
    multiplier: 0.27777777777777777777  # (divide by 3.6)
    offset: 0.0

Existing examples:

https://github.com/COVESA/vss-tools/blob/code_generation/contrib/vspec2aaproperties/vspec2prop_mapping.yml

Vehicle.Speed:
  #convertFloatLinear
  aospId: VehicleProperty::PERF_VEHICLE_SPEED
  aospArea: VehicleArea::GLOBAL
  multiplier: 0.27777777777777777777  # (divide by 3.6)
  offset: 0.0

https://github.com/eclipse/kuksa.val.feeders/blob/main/dbc2val/mapping/mapping.md
https://github.com/eclipse/kuksa.val.feeders/blob/main/dbc2val/mapping/vss_3.1.1/dbc_overlay.vspec

Vehicle.Chassis.SteeringWheel.Angle:
  datatype: int16
  type: sensor
  dbc:
    signal: SteeringAngle129
    interval_ms: 100
    transform:
      math: "floor(x+0.5)"

[erikbosch]

Discussion:

• Erik: Stored in DEG github?
• Ulf: Could make sense