USI Stylus, LetSketch Tablet Driver, Better Apple Magic Device Support In Linux 5.17
First up, there is USI stylus/pen support with Linux 5.17. USI is the Universal Stylus Initiative for supported styluses/pens that would work across devices supporting the standard. Google has been backing USI for Chromebooks and other major IHVs/ISVs have been backing USI for much more convenient stylus support across devices. Intel worked out the USI standards support for the Linux kernel.
A new HID driver this cycle is the LetSketch tablet driver for the LetSketch / VSON WP9620N drawing tablet. The tablet itself has also been sold under other brands too. The hardware can work without this specialized driver but in that generic case only part of the active drawing area works and the stylus buttons do not behave as desired. Just over 300 lines of new code gets the LetSketch driver in its initial form.
The HID updates also include support for the Apple 2021 Magic Keyboard (both models with number pad and fingerprint reader), FN key mapping for the latest Magic keyboard, support for reporting the Magic Keyboard battery level when connected over USB, and other improvements.
Other HID work for Linux 5.17 includes a quirk for devices that need invertex X/Y axes, core clean-ups, improving the locking performance for the raw HID code, power management wake-up support for the i2c HID driver, and other improvements.
See this pull request for the list of HID feature additions this cycle.