078beafb2d
It is far too easy to forget to set FWUPD_DEVICE_FLAG_NO_GUID_MATCHING for new
plugins, and without it it all works really well *until* a user has two devices
of the same type installed at the same time and then one 'disappears' for hard
to explain reasons. Typically we only need it for replug anyway!
Explicitly opt-in to this rarely-required behaviour, with the default to just
use the physical and logical IDs. Also document the update behavior for each
plugin to explain why the flag is being used.
This allows you to have two identical Unifying plugged in without one of them
being hidden from the user, at the same time allowing a HIDRAW<->USB transition
when going to and from bootloader and runtime modes.
This removes the workaround added in 99eb3f06b6.
Fixes https://github.com/fwupd/fwupd/issues/2915
2.0 KiB
Elan TouchPad
Introduction
This plugin allows updating Touchpad devices from Elan. Devices are enumerated using HID and raw I²C nodes. 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.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
Additionally another instance ID is added which corresponds to the IC type & module ID:
ELANTP\ICTYPE_09&MOD_1234
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 touchpad 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:0x17EF
Quirk use
This plugin uses the following plugin-specific quirks:
| Quirk | Description | Minimum fwupd version |
|---|---|---|
ElantpIcPageCount |
The IC page count | 1.4.6 |
ElantpIapPassword |
The IAP password | 1.4.6 |
External interface access
This plugin requires ioctl access to HIDIOCSFEATURE and HIDIOCGFEATURE.