Touch and button adaptation

Complete display geometry and interrupt/DMA setup. Record touch-controller model, firmware, matrix geometry, physical orientation, bus wiring, reset/IRQ pins and the OS HID ABI.

Use driver build integration to connect initialization, archive recipes and the OS ABI, then run this page's hardware checks.

Sources and interfaces

These links identify reviewed source revisions. Match interfaces to the selected SoC, component and OS versions. Files in UniXNU-sheng provide board integration examples.

Implementation	Source	What to read and implement
Bus and sensor	GeniSpi.h, NvtProtocol.h	nvt_bus, chip identification, firmware download and frame reads
Contact processing	NvtTouchCore.c	Matrix processing and contact tracking for the supported sensor
Board integration	TouchBoard.h, TouchProbe.cpp	Power/reset, transport callbacks, interrupt handling and coordinates
OS reports	NativeHidInput.cpp, ButtonProbe.cpp	IOHIDDevice, report descriptors, coherent contact snapshots and button events

1. Select the transport and sensor protocol

Read QcomGeniSpi, ShengNovatekTouch and ShengHidInput. Their responsibilities are:

For a different sensor, implement its identification, firmware and report protocol. For a different bus controller, implement the transfer/delay callbacks used by nvt_bus when reusing the Novatek protocol.

Implement nvt_bus.xfer as one full-duplex transfer with chip select held throughout. Supply caller-owned buffers and the delay callback from NvtProtocol.h. Call nvt_identify, nvt_fw_parse, nvt_download_firmware and nvt_read_frame in that order, checking each return code. On download failure, preserve stage, CRC and SRAM-readback diagnostics before retrying. Publish decoded coordinates, IDs and contact count as one coherent frame for the HID consumer.

2. Adapt the board path

1. Define the target's controller windows, bus mode/rate, GPIOs, interrupt and SMMU stream from its DTS and clock/pin definitions. TouchBoard.h is a board data-layout reference.
2. Implement power/reset ownership and verify engine firmware, pins and clocks.
3. Set DMA addressing and cache maintenance for the target SMMU context.
4. Read the chip ID, then load its firmware and check the returned geometry.
5. Decode complete frames and map coordinates to the display's orientation.
6. Check stable contact IDs, simultaneous contacts, edge behavior and release.

The Novatek processing core uses a 40 × 60 matrix. Verify geometry and bounds when adapting its firmware or processing core. Firmware extraction is owned by the device's scripts/gen-touch-firmware.py and proprietary-file inventory.

sheng's sheng-touch=1, 2, 3 and 4 select resource inspection, clocks/pins, controller identification, then firmware/scanning. Use those stages only after adapting the hardware values consumed by that stage.

Expected result: coherent contact frames in display coordinates, including lift events. The HID layer consumes native_touch_* through a sequence counter; preserve snapshot consistency when replacing the producer.

3. Publish HID reports

Qualify IOHIDFamily methods and object layouts against the selected kernelcache. The sheng archive recipe uses a prelinked candidate and ABI records; see build inputs. Adapt the report descriptor, logical coordinate ranges and contact limits to the sensor.

Select the sensor, transport and HID components in the complete component list. The sheng display recipe links the sensor and bus objects; its HID recipe binds the OS interface. sheng-touch-hid=1 enables sheng's touch publication path. From the assembled target tree, inspect their integration:

rg -n 'TouchProbe|GeniSpi|NvtProtocol|NvtTouchCore|NvtFirmware' scripts/build-gop-legacy-display.py
rg -n 'native_touch_|ReportDescriptor' drivers/ShengHidInput/NativeHidInput.cpp

Expected result: the OS receives correct down, move and up reports for each contact, and UI gestures follow the panel orientation.

4. Adapt physical buttons

Use ButtonProbe.cpp in the source map as a reference for interrupt sampling and HID button events.

Map the target's GPIO or PMIC inputs, polarity, ownership, interrupt routing and acknowledgement. Access only the PMIC peripherals owned by the selected execution environment. Adapt BootResetCore.h helpers where the SPMI controller differs. Connect press/release state to the HID consumer report. sheng uses report 2 bits for Power, Volume Increment and Volume Decrement and enables this with sheng-buttons=1.

Expected result: every press and release produces the expected report, including held and simultaneous buttons, with bounded interrupt activity.

Next step

Rebuild through Building, record touch and buttons separately, then continue with GPU adaptation.