Use WDF_DEVICE_PROPERTY_DATA to store calibration parameters as a binary buffer under the Device Parameters\TouchCalibration key.
Introduction In the rapidly evolving landscape of embedded systems and human-machine interfaces, the demand for precision touch input has never been higher. From industrial control panels to medical-grade diagnostic displays and automotive infotainment systems, the accuracy of a touchscreen is paramount. At the heart of this accuracy lies a critical software component: the Windows driver . kmdf hid minidriver for touch i2c device calibration best
PTOUCH_CALIBRATION_INPUT input = NULL; WDFMEMORY memory; NTSTATUS status = STATUS_SUCCESS; // 1. Retrieve raw/display point pairs from user-mode app status = WdfRequestRetrieveInputMemory(Request, &memory); input = (PTOUCH_CALIBRATION_INPUT)WdfMemoryGetBuffer(memory, NULL); At the heart of this accuracy lies a
[ X_calibrated = A \cdot X_raw + B \cdot Y_raw + C ] [ Y_calibrated = D \cdot X_raw + E \cdot Y_raw + F ] Send HID Feature Report to I2C device (Report
// 4. Send HID Feature Report to I2C device (Report ID 0x03) UCHAR featureReport[32] = 0; featureReport[0] = 0x03; // Report ID for calibration RtlCopyMemory(&featureReport[1], matrix, sizeof(matrix)); status = WriteI2C_HIDFeatureReport(DeviceContext, featureReport, 32);
// 5. Complete request WdfRequestComplete(Request, status); return status; The journey to building the best KMDF HID minidriver for touch I2C device calibration is not merely about writing code—it is about mastering the interplay between hardware limits, kernel-mode constraints, and user expectations.