FreeBSD source tree https://cgit-dev.freebsd.org/src/atom?h=main 2026-07-12T17:11:10Z 2026-07-12T17:11:10Z Abdelkader Boudih freebsd@seuros.com 2026-07-12T17:11:07Z urn:sha1:4085d1991e2a9e155e3d928955ce8ba53512b8da The Wacom ExpressKey Remote (ACK-411050) is a wireless button pad with 18 programmable buttons and a touch ring, used as a companion device with Wacom tablets. It communicates via a USB wireless receiver (0x056a:0x0331) using a vendor-specific HID report (ID 0x11). This driver exposes the device via evdev: - 18 buttons: BTN_0–BTN_Z, BTN_BASE, BTN_BASE2 - Touch ring position via ABS_WHEEL (0–71; reports 0 on release) - Pad activity marker via ABS_MISC (set to 15/PAD_DEVICE_ID when any input is active, 0 when idle that matches Linux wacom driver convention) - Remote serial number via MSC_SERIAL (for userland per-remote identification) Battery level, charging state, and touch ring mode (3 LEDs, values 0–2) are exposed as per-device sysctls (dev.hidwacom.0.battery, .charging, .ring_mode) rather than overloading evdev misc codes. The ring mode sysctl is preserved across device idle periods. Protocol was decoded from USB traffic analysis and cross-referenced against the Linux wacom_remote_irq() implementation in drivers/hid/wacom_wac.c. Reviewed by: adrian Differential Revision: https://reviews.freebsd.org/D56729 Discussed with: ziaee