## Introduction

This plugin allows updating Touchpad devices from Elan. Devices are enumerated using HID and raw I²C nodes. The I²C mode is used for ABS devices and firmware recovery of HID devices.

## 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.emc.elantp`

## GUID Generation

These device uses the standard DeviceInstanceId values, e.g.

- `HIDRAW\VEN_04F3&DEV_3010`

Additionally another instance ID is added which corresponds to the module ID:

- `HIDRAW\VEN_04F3&DEV_3010&MOD_1234`

These devices also use custom GUID values for the IC configuration, e.g.

- `ELANTP\ICTYPE_09` (only-quirk)

Additionally another instance ID is added which corresponds to the IC type & module ID:

- `ELANTP\ICTYPE_09&MOD_1234`

Additionally another instance ID is added which corresponds to the IC Type & module ID and Driver in order to distinguish HID/ABS devices:

- `ELANTP\ICTYPE_09&MOD_1234&DRIVER_HID` -> HID Device
- `ELANTP\ICTYPE_09&MOD_1234&DRIVER_ELAN_I2C` -> ABS Device

## Update Behavior

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

For HID devices, 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.

For ABS devices, on flash failure the device is nonfunctional, but it could be recovered by the same i2c device.

## Vendor ID Security

The vendor ID is set from the HID vendor, for example set to `HIDRAW:0x17EF`

## Quirk Use

This plugin uses the following plugin-specific quirks:

### ElantpIcPageCount

The IC page count.

Since: 1.4.6

### ElantpIapPassword

The IAP password.

Since: 1.4.6

## External Interface Access

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

## Version Considerations

This plugin has been available since fwupd version `1.5.0`.