iichid(4)

iichid4

I2c hid transport driver

Usage

To compile this driver into the kernel, place the following lines in your kernel configuration file:

device iichid

Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):

iichid_load="YES"

Overview

The iichid driver provides a interface to I2C Human Interface Devices (HIDs).

Sysctl variables

Next parameters are available as sysctl(8) variables. Debug parameter is available as loader(8) tunable as well.

dev.iichid.*.sampling_rate_fast

Active sampling rate in num/second (for sampling mode).

dev.iichid.*.sampling_rate_slow

Idle sampling rate in num/second (for sampling mode).

dev.iichid.*.sampling_hysteresis

Number of missing samples before enabling of slow mode (for sampling mode).

hw.iichid.debug

Debug output level, where 0 is debugging disabled and larger values increase debug message verbosity. Default is 0.

Releases

15 releases since FreeBSD 13.0-RELEASE; the text changed 3 times.

  1. 13.0–13.2
  2. 13.3–13.5
  3. 14.0–14.5
  4. 15.0–16.0

Bugs

The iichid does not support GPIO interrupts yet. In that case iichid enables sampling mode with periodic polling of hardware by driver means. See dev.iichid.*.sampling_* sysctl(8) variables for tuning of sampling parameters.

History

The iichid driver first appeared in FreeBSD 13.0.

Authors

The iichid driver was written by Marc Priggemeyer ⟨[email protected]⟩ and Vladimir Kondratyev ⟨[email protected]⟩.

This manual page was written by Vladimir Kondratyev ⟨[email protected]⟩.

From base 16.0-CURRENT-20261027-61c70dc16a79 in FreeBSD 16.0-CURRENT (2026-10-27). Parsed by carta from the page's mdoc source.