The all-Rust wdk-sys IddCx driver now initializes its adapter on the RTX box:
IddCxAdapterInitAsync -> 0x0, EvtIddCxAdapterInitFinished fires, device Status=OK.
ROOT CAUSE (found via cdb wt-trace of iddcx!IddCxImplAdapterInitAsync + the upstream
virtual-display-rs source): IDDCX_ENDPOINT_DIAGNOSTIC_INFO.GammaSupport was left zeroed
= IDDCX_FEATURE_IMPLEMENTATION_UNINITIALIZED (0), which the framework adapter validator
(ddivalidation.cpp:797) rejects with STATUS_INVALID_PARAMETER. Must be NONE (1).
Also required (matched to the proven-working upstream virtual-display-rs, installed +
verified Status=OK on the same box):
- caps Flags = NONE (SDR). CAN_PROCESS_FP16 needs a newer contract than UmdfExtensions=
IddCx0102 grants; deferred to STEP 7 (HDR).
- SDR config: only the 7 required callbacks (+ DeviceIoControl for the proto control
plane). The *2/gamma/HDR-metadata/query-target-info callbacks are FP16-obligated and
rejected without FP16 caps; they return in STEP 7.
- device WDF context type on WdfDeviceCreate; adapter WDF context type on the init attrs.
Debugging note: cdb is reliable via live-attach (go-file gate to avoid the
IsDebuggerPresent race) but cdb -z static hangs on the VM; iddcx WPP needs the control
GUID (TMF GUIDs are not it). Diagnostics trimmed; log.rs dbglog kept for STEP 4+.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
enricobuehler
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