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.\" $NetBSD: uhid.4,v 1.13 2001/12/29 14:41:59 augustss Exp $
.\"
.\" Copyright (c) 1999, 2001 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Lennart Augustsson.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
.\" $FreeBSD$
.\"
.Dd November 22, 2006
.Dt UHID 4
.Os
.Sh NAME
.Nm uhid
.Nd USB generic HID support
.Sh SYNOPSIS
To compile this driver into the kernel,
place the following line in your
kernel configuration file:
.Bd -ragged -offset indent
.Cd "device uhid"
.Ed
.Pp
Alternatively, to load the driver as a
module at boot time, place the following line in
.Xr loader.conf 5 :
.Bd -literal -offset indent
uhid_load="YES"
.Ed
.Sh DESCRIPTION
The
.Nm
driver provides support for all HID (Human Interface Device) interfaces
in USB devices that do not have a special driver.
.Pp
The device handles the following
.Xr ioctl 2
calls:
.Bl -tag -width indent
.It Dv USB_GET_REPORT_ID Pq Vt int
Get the report identifier used by this HID report.
.It Dv USB_GET_REPORT_DESC Pq Vt "struct usb_ctl_report_desc"
Get the HID report descriptor.
Using
this descriptor the exact layout and meaning of data to/from
the device can be found.
The report descriptor is delivered
without any processing.
.Bd -literal
struct usb_ctl_report_desc {
    int     ucrd_size;
    u_char  ucrd_data[1024];	/* filled data size will vary */
};
.Ed
.It Dv USB_SET_IMMED Pq Vt int
Sets the device in a mode where each
.Xr read 2
will return the current value of the input report.
Normally
a
.Xr read 2
will only return the data that the device reports on its
interrupt pipe.
This call may fail if the device does not support
this feature.
.It Dv USB_GET_REPORT Pq Vt "struct usb_ctl_report"
Get a report from the device without waiting for data on
the interrupt pipe.
The
.Va report
field indicates which report is requested.
It should be
.Dv UHID_INPUT_REPORT ,
.Dv UHID_OUTPUT_REPORT ,
or
.Dv UHID_FEATURE_REPORT .
This call may fail if the device does not support this feature.
.Bd -literal
struct usb_ctl_report {
	int ucr_report;
	u_char	ucr_data[1024];	/* used data size will vary */
};
.Ed
.It Dv USB_SET_REPORT Pq Vt "struct usb_ctl_report"
Set a report in the device.
The
.Va report
field indicates which report is to be set.
It should be
.Dv UHID_INPUT_REPORT ,
.Dv UHID_OUTPUT_REPORT ,
or
.Dv UHID_FEATURE_REPORT .
This call may fail if the device does not support this feature.
.El
.Pp
Use
.Xr read 2
to get data from the device.
Data should be read in chunks of the
size prescribed by the report descriptor.
.Pp
Use
.Xr write 2
to send data to the device.
Data should be written in chunks of the
size prescribed by the report descriptor.
.Sh FILES
.Bl -tag -width ".Pa /dev/uhid?"
.It Pa /dev/uhid?
.El
.Sh SEE ALSO
.Xr usbhidctl 1 ,
.Xr usb 4
.Sh HISTORY
The
.Nm
driver
appeared in
.Nx 1.4 .
This manual page was adopted from
.Nx
by
.An Tom Rhodes Aq Mt trhodes@FreeBSD.org
in April 2002.