AnyPS5/docs/dev/debt/libSceMbus.md

libSceMbus technical debt

Silent stubs

• libSceMbus implements only the no-device path: initialization and termination succeed, no device events are reported, device queries return no entries and sceDeviceServiceGetGeneration always returns 0, as the device set never changes. The generation a console starts at is unmeasured; SharpProspero documents int sceDeviceServiceGetGeneration() as a counter that advances when the device set changes

Unknown function info

• sceDeviceServiceQueryDeviceInfo_: the 112-byte device-info layout and the third argument's meaning remain unresolved. The second argument is a six-byte HID usage filter pointer, not an integer. Initialization takes an optional 16-byte parameter structure with an optional thread configuration; custom scheduling throws because the host has no event worker. sceDeviceServiceGetEventState takes a clear flag, not a device type.

• libSceMbus firmware 3.20 pending exports - 52 remaining symbol names are present in the PS5 3.20 libSceMbus export list. Their signatures and console behaviour are unverified. The declarations use the existing no-parameter unknown-signature convention solely to resolve imports, and every call throws through NotImplemented_nid_no_patch.

• sceMbusAddHandleByDeviceId: the six-argument ABI is confirmed, including the 64-bit device ID. The meanings of the last three 32-bit fields require the device-service backend.

• sceMbus control and handle registration: argument positions and transmitted widths are recovered for control acquisition, handle registration, process attachment, user binding and device-ID conversion. Several scalar field meanings still depend on the service protocol; the 64-bit control value and unnamed registration fields must not be interpreted as pointers. AcquireControlList returns a constant error without reading its incoming arguments, so its source signature remains unresolved.

• sceMbus debug process and device queries: process information is transmitted as 16 bytes, startup input/output as eight bytes, control status as 24 bytes, internal information as 2832 bytes and priority information as 3088 bytes. Device enumeration writes a 32-bit count followed by 396-byte entries. These pointee fields and the semantics of unnamed process flags remain unresolved; declarations use distinct incomplete types instead of guessing their fields.

• sceMbus event subscriptions: the subscription transports two 32-bit and two 64-bit fields whose service-side meanings remain unresolved. EventCreate uses 80-byte queue records and copies a 16-byte callback table; callback signatures and event fields still require the dispatch path. EventCallbackFuncsInit only clears memory and has no defined return value; its protected stub retains the existing integer return. Eight dump/BGM wrappers have confirmed zero-argument ABIs. EventBusStatusChangeUnsubscribe ignores its first incoming argument and consumes a 32-bit second argument; its first parameter type remains unresolved.