Two latent bugs kept all SMC telemetry dead — service never opened, and every struct call would have been rejected even if it had.
Fixes
Service name: IOServiceMatching("AppleSMCClient") → IOServiceMatching("AppleSMC") (MMAppleSMCClient.m:60) — AppleSMCClient is the user-client class, not the kernel service (ARCHITECTURE.md §3.1).
Struct layout: removed #pragma pack(1) from MMSMCDefines.h. Packed SMCKeyData_t is 74 bytes; the SMC user client requires the canonical 80-byte layout and rejected every IOConnectCallStructMethod with kIOReturnBadArgument. Verified live on Intel hardware — unpacked calls return #KEY info (ui32).
Alert input: context.batteryLevel now prefers the SMC-independent batteryHealth path (currentCapacity/maxCapacity), falling back to the power provider — low-battery alerts can fire even if SMC is unavailable.
Verified
xcodebuild build test -destination 'platform=macOS,arch=x86_64' — 93/93 pass; testSMCClientSingletonAndKeyCount now exercises a real open connection (totalKeyCount > 0).
swiftlint — 0 violations.
Live probe on this machine: IOServiceMatching("AppleSMC") → open OK, GetKeyInfo returns valid data.
## Summary
Two latent bugs kept all SMC telemetry dead — service never opened, and every struct call would have been rejected even if it had.
### Fixes
1. **Service name**: `IOServiceMatching("AppleSMCClient")` → `IOServiceMatching("AppleSMC")` (`MMAppleSMCClient.m:60`) — `AppleSMCClient` is the user-client class, not the kernel service (ARCHITECTURE.md §3.1).
2. **Struct layout**: removed `#pragma pack(1)` from `MMSMCDefines.h`. Packed `SMCKeyData_t` is 74 bytes; the SMC user client requires the canonical 80-byte layout and rejected every `IOConnectCallStructMethod` with `kIOReturnBadArgument`. Verified live on Intel hardware — unpacked calls return `#KEY` info (`ui32`).
3. **Alert input**: `context.batteryLevel` now prefers the SMC-independent `batteryHealth` path (`currentCapacity/maxCapacity`), falling back to the power provider — low-battery alerts can fire even if SMC is unavailable.
### Verified
- `xcodebuild build test -destination 'platform=macOS,arch=x86_64'` — 93/93 pass; `testSMCClientSingletonAndKeyCount` now exercises a real open connection (`totalKeyCount > 0`).
- `swiftlint` — 0 violations.
- Live probe on this machine: `IOServiceMatching("AppleSMC")` → open OK, GetKeyInfo returns valid data.
Fixes #32.
Two latent bugs kept all SMC telemetry dead:
- IOServiceMatching("AppleSMCClient") never matched — the kernel service
is AppleSMC, so openWithError always failed and every SMC-gated provider
(thermal, fan, component, power) reported unavailable.
- #pragma pack(1) shrank SMCKeyData_t to 74 bytes; the SMC user client
requires the canonical 80-byte layout and rejected every
IOConnectCallStructMethod with kIOReturnBadArgument. Verified live on
Intel hardware: unpacked calls succeed and return key data.
Also sources the alert engine's batteryLevel from the SMC-independent
batteryHealth path (currentCapacity/maxCapacity), falling back to the
power provider.
Generated with [Devin](https://devin.ai)
Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
Blocking a user prevents them from interacting with repositories, such as opening or commenting on pull requests or issues. Learn more about blocking a user.
Summary
Two latent bugs kept all SMC telemetry dead — service never opened, and every struct call would have been rejected even if it had.
Fixes
IOServiceMatching("AppleSMCClient")→IOServiceMatching("AppleSMC")(MMAppleSMCClient.m:60) —AppleSMCClientis the user-client class, not the kernel service (ARCHITECTURE.md §3.1).#pragma pack(1)fromMMSMCDefines.h. PackedSMCKeyData_tis 74 bytes; the SMC user client requires the canonical 80-byte layout and rejected everyIOConnectCallStructMethodwithkIOReturnBadArgument. Verified live on Intel hardware — unpacked calls return#KEYinfo (ui32).context.batteryLevelnow prefers the SMC-independentbatteryHealthpath (currentCapacity/maxCapacity), falling back to the power provider — low-battery alerts can fire even if SMC is unavailable.Verified
xcodebuild build test -destination 'platform=macOS,arch=x86_64'— 93/93 pass;testSMCClientSingletonAndKeyCountnow exercises a real open connection (totalKeyCount > 0).swiftlint— 0 violations.IOServiceMatching("AppleSMC")→ open OK, GetKeyInfo returns valid data.Fixes #32.
Two latent bugs kept all SMC telemetry dead: - IOServiceMatching("AppleSMCClient") never matched — the kernel service is AppleSMC, so openWithError always failed and every SMC-gated provider (thermal, fan, component, power) reported unavailable. - #pragma pack(1) shrank SMCKeyData_t to 74 bytes; the SMC user client requires the canonical 80-byte layout and rejected every IOConnectCallStructMethod with kIOReturnBadArgument. Verified live on Intel hardware: unpacked calls succeed and return key data. Also sources the alert engine's batteryLevel from the SMC-independent batteryHealth path (currentCapacity/maxCapacity), falling back to the power provider. Generated with [Devin](https://devin.ai) Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>