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XHCI(4) FreeBSD Kernel Interfaces Manual XHCI(4)
NAME
xhci - USB eXtensible Host Controller driver
SYNOPSIS
options USB_DEBUG
device xhci
DESCRIPTION
The xhci driver provides support for the USB eXtensible Host Controller
Interface, which allows use of USB 1.0, 2.0 and 3.0 devices on the same
USB port.
The XHCI controller supports USB connection speeds from 5.0Gbps and above
when using USB 3.x compliant devices.
HARDWARE
The xhci driver supports XHCI compatible controllers having PCI class 12
(serial bus), subclass 3 (USB) and programming interface 48 (XHCI).
SYSCTL VARIABLES
The following variables are available as both sysctl(8) variables and
loader(8) tunables:
hw.usb.xhci.debug
Set debug output level, where 0 is debugging disabled and larger
values increase debug message verbosity. The default value is 0.
hw.usb.xhci.dcepquirk
Set to enable quirk for deconfiguration of endpoints. The
default value is 0.
hw.usb.xhci.ctlquirk
Set to submit full USB control request as one job, up to
64kBytes. Else the USB control request will be split into
multiple smaller requests. The default value is 1.
hw.usb.xhci.streams
Set to enable USB streams support. The default value is 0.
hw.usb.xhci.route
Set bitmap for switching EHCI ports to the XHCI controller. The
default value is 0.
hw.usb.xhci.polling
Set to use a timer to poll the interrupt handler. The default
value is 0.
hw.usb.xhci.dma32
Set to only use 32-bit DMA for the XHCI controller. The default
value is 0.
hw.usb.xhci.ctlstep
Set to enable control endpoint status state stepping. The
default value is 0.
SEE ALSO
ehci(4), ohci(4), uhci(4) and usb(4)