async-hid

async-hid FreeBSD hardware checks

Hand-run programs that verified the FreeBSD hidraw(4) backend against real devices. Removed from the upstream async-hid repo in PR #49: they mostly duplicated the shared examples, differing only in which device they select, so they were noise for anyone reading the repo for API guidance.

Kept here because they still document which paths were exercised on hardware.

Design of the backend itself: async-hid-freebsd-backend.md (starter module: async-hid-freebsd-skeleton.rs). Kernel side (EVFILT_WRITE in hidraw(4)): ../docs/hidraw_kqueue_evfilt_write.md.

Running

They are examples/-shaped, not standalone crates. Drop one into a checkout:

cp examples/freebsd_read_mouse.rs ~/async-hid/examples/
cd ~/async-hid
cargo run --example freebsd_read_mouse

Most select a device by usage page and usage id, so no editing is needed. freebsd_read_by_path and freebsd_read_mouse_by_vid take arguments:

cargo run --example freebsd_read_by_path /dev/hidraw0 5
cargo run --example freebsd_read_mouse_by_vid 0x046d

Coverage

File	Path exercised
freebsd_read_mouse.rs	enumerate filtered by usage page, read_input_report
freebsd_read_mouse_by_vid.rs	enumerate filtered by vendor id plus usage page
freebsd_read_by_path.rs	query_devices with DeviceId::DevPath, numbered reports
freebsd_read_gamepad.rs	read_input_report on a gamepad
freebsd_feature_gamepad.rs	HIDIOCGFEATURE via AsyncHidFeatureHandle
freebsd_write_kbd_leds.rs	write_output_report

freebsd_read_by_path.rs is the only one covering DeviceId::DevPath lookup; no shared example does. Worth folding into open_device.rs upstream some day.

Runtime requirements

FreeBSD 13+, hw.usb.usbhid.enable=1, hidraw module loaded. Nodes are 0600 root:operator, so non-root access needs a devfs.rules(5) entry. Without it enumerate returns nothing instead of an error.