#### Plugin: Focal Touchpad and touchscreen

## Introduction

This plugin allows updating Touch devices from FocalTech. Devices are enumerated using HID. The I²C mode is used for firmware recovery.

## Firmware Format

The daemon will decompress the cabinet archive and extract a firmware blob in an unspecified binary file format.

This plugin supports the following protocol ID:

- `tw.com.focal.tp`

## GUID Generation

These devices use the standard DeviceInstanceId values, e.g.

- `HIDRAW\VEN_2808&DEV_3002`
- `HIDRAW\VEN_2808&DEV_1006`

## Update Behavior

The device usually presents in HID mode, and the firmware is written to the device by switching to a IAP mode where the Touch device is nonfunctional. Once complete the device is reset to get out of IAP mode and to load the new firmware version.

On flash failure the device is nonfunctional, but is recoverable by writing to the i2c device. This is typically much slower than updating the device using HID and also requires a model-specific HWID quirk to match.

## Vendor ID Security

The vendor ID is set from the HID vendor, for example set to `HIDRAW:0x2808`

## Quirk Use

This plugin uses the following plugin-specific quirk:

- `FocalTouchVerifyId`: The first and second byte of the hardware verification ID.

## External Interface Access

This plugin requires ioctl access to `HIDIOCSFEATURE` and `HIDIOCGFEATURE`.

## Version Considerations

This plugin has been available since fwupd version `2.1.1`.

## Owners

Anyone can submit a pull request to modify this plugin, but the following people should be consulted before making major or functional changes:

- Wayne Huang: `waynehuang2022`