!!link!!: Kmdf Hid Minidriver For Touch I2c Device Calibration Best

For Kernel-Mode Driver Framework (KMDF) HID minidrivers on Windows, the HID over I2C driver

The following example code illustrates a basic calibration implementation in a KMDF HID minidriver: kmdf hid minidriver for touch i2c device calibration best

1. Show targets on screen.
2. Read raw coordinates via IOCTL_TOUCH_GET_RAW (another private IOCTL that bypasses calibration).
3. Compute transform.
4. Write back via IOCTL_TOUCH_SET_CALIBRATION.

• Byte 0: command (0=start,1=cancel,2=status)
• Byte 1: status (0=idle,1=running,2=success,3=error)
• Byte 2-3: last_error_rms (uint16)
• Remaining: reserved

// Set the gain and offset values i2cInterface->WriteRegister(I2C_ADDRESS, REG_GAIN_X, CalibrationData->gainX); i2cInterface->WriteRegister(I2C_ADDRESS, REG_OFFSET_Y, CalibrationData->offsetY);

Testing and Validation

• Store calibration in registry.
• Apply transform inside the report processing path with minimal overhead.
• Protect parameters with a lock.
• Never alter the HID descriptor.
• Validate thoroughly with HLK tools.

KMDF HID Minidriver for Touch I2C Device — Calibration Guide

Overview

This document describes how to implement calibration support in a KMDF-based HID minidriver for a touch controller connected over I²C. It covers design goals, data flow, required HID usages and reports, driver components, calibration algorithms, persistent storage, and testing/validation steps. For Kernel-Mode Driver Framework (KMDF) HID minidrivers on