Dennis HilkLinux diagnosticsDE

Chipsets & PCIe

Intel Kaby Lake PCH-H SMBus

A motherboard SMBus host profile with controller-level evidence and passive adapter inspection.

Editorial source review: Share public profileOpen in the identification tool
On this page
  1. Overview & identity
  2. Driver & binding
  3. Firmware
  4. Read-only diagnostics
  5. Limitations & related issues
  6. References

Overview & identity

The source defines 0xa2a3 as KABYLAKE_PCH_H_SMBUS and includes it in i801_ids. That is a PCH host-controller family, not a precise CPU or system board. The table also assigns TCO-related feature handling, which must not be confused with a sensor-model match.

Curated identifiers
pci 8086:a2a3

A numeric match establishes a candidate family within the reviewed evidence. Marketing names, board variants, subsystem conditions and successful operation remain separate questions.

Driver & binding

The i2c_i801 kernel candidate manages this SMBus host while attached components have their own client drivers. A registered SMBus adapter does not guarantee that a particular fan or temperature channel is exported. Keep host initialization, client enumeration and hardware-monitoring measurements as separate observations.

  • i2c_i801 — kernel driver/module candidate

Detected, bound, operational: learn the difference

Firmware

No host payload established here

No host-loaded firmware filename is established for this SMBus host by the reviewed driver. BIOS/ACPI can still determine visibility and access ownership, and attached devices may have their own firmware. A filename-free controller entry is not a firmware-free motherboard claim.

Inspect firmware packaging on your distribution

Read-only diagnostics

Run one displayed command at a time. Replace uppercase placeholders with the affected device, interface or module from your own output. Commands are never executed here. Read-only output can still contain private identifiers.

Read this function and its bound driver

lspci -nnk -s BDF

Replace BDF with the address of the Intel Kaby Lake PCH-H SMBus function. The summary normally needs no sudo. Numeric ID and the “driver in use” observation are stronger evidence than a descriptive name or candidate-module list.

Confirm the PCI driver owner

readlink /sys/bus/pci/devices/BDF/driver

Use a full domain:bus:slot.function BDF. This normally needs no sudo and only reads a symlink. The last component is the bound driver; no link records an unbound/absent function, not a missing software package.

Read registered adapter names without probing

cat /sys/class/i2c-adapter/i2c-*/name

This reads existing sysfs metadata and normally needs no sudo. It does not send I2C/SMBus transactions. The list covers all registered adapters, so a name alone does not map an adapter to BDF or identify a sensor client; absent entries describe registration state.

Read current-boot controller messages

journalctl -k -b --no-pager

Separate SMBus host initialization or resource-ownership errors from messages of unrelated sensor clients. Journal access may require local group membership; failure to read it is not controller failure.

Limitations & related issues

A PCI host-controller match does not identify every I2C/SMBus client or authorize active address probing. The read-only adapter list does not establish temperature accuracy or sensor support. No hidden-function enablement, bus scan or controller register change is included.

These guides are linked for relevant observations, not as known defects of every device in this family.

    Choose a hardware diagnostic workflow · Inspect a log excerpt in Fix Lab

    References

    Source review records a checked implementation or document, not a reproduced hardware test. Version-specific tables do not establish a minimum kernel or guaranteed operation.