Being worked on for a while by Lenovo engineer Vishnu Sankar is nicely handling support for double-tap functionality with TrackPoints on ThinkPads under Linux. The sixth iteration of this enablement work was posted today and is just documentation updates, so it’s looking like this new TrackPoint doubletap code could soon be crossing the threshold for the mainline Linux kernel.
Vishnu Sankar has been leading the effort of TrackPoint double-tap handling under Linux with better integration between the Trackpoint driver and ThinkPad ACPI driver code. Double-tap support requires cooperation with the firmware and for recognizing the hardware’s support. With these patches doubletap support would be enabled by default on capable devices while a sysfs control allows for toggling the feature if so desired.
This double-tap functionality in turn works and can be toggled without any user-space configuration. The sysfs file is /sys/devices/platform/thinkpad_acpi/doubletap_enable for setting it to 0 if wanting to disable double-tap hotkey events or 1 to allow for the double-tap hotkey events, as is the default. Previously the thinkpad_acpi code just unconditionally enabled the double-tap support.
The v6 patches out today just bring a documentation formatting fix, so it’s looking like this cleaned-up TrackPoint double-tap code is settling down and could soon be ready for the mainline kernel.
