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Userspace daemon for Intel Precise Touch & Stylus

IPTSD

This is the userspace touch processing daemon for Microsoft Surface devices using Intel Precise Touch technology.

The daemon will read incoming HID reports containing raw capacitive touch data, stylus coordinates and DFT pen measurements, and create standard input events from it using uinput devices.

Installing

IPTSD is included in the linux-surface repository. This is the recommended way of installing it.

Important: Support on Debian based distributions only goes back to Debian 11 / Ubuntu 22.04.

If you want to try out changes that are not yet released, GitHub Actions builds Arch Linux, Debian and Fedora packages for every commit. You'll need to be signed in to GitHub, then go to https://github.com/linux-surface/iptsd/actions, select the latest successful workflow and download the artifact named <your distro>-latest.

Building

To build IPTSD from source, you need to install the following dependencies:

  • A C++ compiler
  • meson
  • ninja
  • CLI11
  • Eigen3
  • fmt
  • inih / INIReader
  • gsl
  • spdlog
  • cmake, because some of our dependencies don't ship pkgconfig files

To build the plotting tools for visualizing data, you need to install a few more dependencies.

  • cairomm
  • SDL2

Most of the dependencies can be downloaded and included automatically by meson, should your distribution not include them.

$ git clone https://github.com/linux-surface/iptsd
$ cd iptsd
$ meson setup build
$ ninja -C build

To run iptsd, you need to determine the ID of the hidraw device of your touchscreen:

$ sudo ./etc/iptsd-find-hidraw

You can then run iptsd with the device path as a launch argument:

$ sudo ./build/src/iptsd /dev/hidrawN

Alternatively, you can install the files you just built to the system. After a reboot, iptsd will get started by udev automatically:

$ sudo ninja -C build install

On Fedora (or any other SELinux enabled distribution) you also need to fix the SELinux contexts:

$ sudo semanage fcontext -a -t systemd_unit_file_t -s system_u /usr/lib/systemd/system/[email protected]
$ sudo semanage fcontext -a -t usr_t -s system_u '/usr/local/bin/ipts.*'

$ sudo restorecon -vF /usr/lib/systemd/system/[email protected]
$ sudo restorecon -vF /usr/local/bin/ipts*

This is only necessary when using ninja install. When you install one of the packages from GitHub Actions, or build your own package, everything will just work.