hid: Import usbhid - USB transport backend for HID subsystem

[wulf]

Summary

This implements hid_if.m methods for HID-over-USB protocol [1].

Also, this adds USBHID_ENABLED kernel option which changes device_probe()
priority and adds/removes PnP records to prefer usbhid over ums, ukbd, wmt
and other USB HID device drivers.

The module is based on uhid(4) driver.

It is disabled by default for now due to conflicts with existing USB HID drivers.

[1] https://www.usb.org/sites/default/files/hid1_11.pdf

[• hselasky]

sys/dev/usb/input/usbhid.c

162

I think this usbd_transfer_stop(xfer) is superfluous.

[wulf]

sys/dev/usb/input/usbhid.c

162

usbd_transfer_stop(xfer) moved to usbhid_intr_stop() routine and replaced with usbd_transfer_drain()