213 lines
6.4 KiB
Groff
213 lines
6.4 KiB
Groff
.\" $NetBSD: usb.3,v 1.13 2000/09/24 02:17:52 augustss Exp $
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.\" Copyright (c) 1999 Lennart Augustsson <augustss@netbsd.org>
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" 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 AUTHOR 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 AUTHOR 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.
|
|
.\"
|
|
.Dd May 11, 1999
|
|
.Dt USB 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm usb ,
|
|
.Nm hid_get_report_desc ,
|
|
.Nm hid_use_report_desc ,
|
|
.Nm hid_dispose_report_desc ,
|
|
.Nm hid_start_parse ,
|
|
.Nm hid_end_parse ,
|
|
.Nm hid_get_item ,
|
|
.Nm hid_report_size ,
|
|
.Nm hid_locate ,
|
|
.Nm hid_usage_page ,
|
|
.Nm hid_usage_in_page ,
|
|
.Nm hid_init ,
|
|
.Nm hid_get_data ,
|
|
.Nm hid_set_data
|
|
.Nd USB HID access routines
|
|
.Sh LIBRARY
|
|
.Lb libusb
|
|
.Sh SYNOPSIS
|
|
.In libusbhid.h
|
|
.Ft report_desc_t
|
|
.Fn hid_get_report_desc "int file"
|
|
.Ft report_desc_t
|
|
.Fn hid_use_report_desc "unsigned char *data" "unsigned int size"
|
|
.Ft void
|
|
.Fn hid_dispose_report_desc "report_desc_t d"
|
|
.Ft hid_data_t
|
|
.Fn hid_start_parse "report_desc_t d" "int kindset"
|
|
.Ft void
|
|
.Fn hid_end_parse "hid_data_t s"
|
|
.Ft int
|
|
.Fn hid_get_item "hid_data_t s" "hid_item_t *h"
|
|
.Ft int
|
|
.Fn hid_report_size "report_desc_t d" "unsigned int id" "hid_kind_t k"
|
|
.Ft int
|
|
.Fn hid_locate "report_desc_t d" "unsigned int usage" "hid_kind_t k" "hid_item_t *h"
|
|
.Ft const char *
|
|
.Fn hid_usage_page "int i"
|
|
.Ft const char *
|
|
.Fn hid_usage_in_page "unsigned int u"
|
|
.Ft int
|
|
.Fn hid_parse_usage_page "const char *name"
|
|
.Ft int
|
|
.Fn hid_parse_usage_in_page "const char *name"
|
|
.Ft void
|
|
.Fn hid_init "const char *file"
|
|
.Ft int
|
|
.Fn hid_get_data "const void *data" "const hid_item_t *h"
|
|
.Ft void
|
|
.Fn hid_set_data "void *p" "const hid_item_t *h" "int data"
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
library provides routines to extract data from USB Human Interface Devices.
|
|
.Ss INTRODUCTION
|
|
USB HID devices send and receive data layed out in a device dependent
|
|
way. The
|
|
.Nm
|
|
library contains routines to extract the
|
|
.Em report descriptor
|
|
which contains the data layout information and then use this information.
|
|
.Pp
|
|
The routines can be divided into four parts: extraction of the descriptor,
|
|
parsing of the descriptor, translating to/from symbolic names, and
|
|
data manipulation.
|
|
.Ss DESCRIPTOR FUNCTIONS
|
|
A report descriptor can be obtained by calling
|
|
.Fn hid_get_report_desc
|
|
with a file descriptor obtained by opening a
|
|
.Xr uhid 4
|
|
device. Alternatively a data buffer containing the report descriptor can be
|
|
passed into
|
|
.Fn hid_use_report_desc .
|
|
The data is copied into an internal structure. When the report descriptor
|
|
is no longer needed it should be freed by calling
|
|
.Fn hid_dispose_report_desc .
|
|
The type
|
|
.Fa report_desc_t
|
|
is opaque and should be used when calling the parsing functions.
|
|
If
|
|
.Fn hid_dispose_report_desc
|
|
fails it will return
|
|
.Fa NULL .
|
|
.Ss DESCRIPTOR PARSING FUNCTIONS
|
|
To parse the report descriptor the
|
|
.Fn hid_start_parse
|
|
function should be called with a report descriptor and a set that
|
|
describes which items that are interesting. The set is obtained
|
|
by or-ing together values
|
|
.Fa "(1 << k)"
|
|
where
|
|
.Fa k
|
|
is an item of type
|
|
.Fa hid_kind_t .
|
|
The function returns
|
|
.Fa NULL
|
|
if the initialization fails, otherwise an opaque value to be used
|
|
in subsequent calls.
|
|
After parsing the
|
|
.Fn hid_end_parse
|
|
function should be called to free internal data structures.
|
|
.Pp
|
|
To iterate through all the items in the report descriptor
|
|
.Fn hid_get_item
|
|
should be called while it returns a value greater than 0.
|
|
When the report descriptor ends it will returns 0; a syntax
|
|
error within the report descriptor will cause a return value less
|
|
than 0.
|
|
The struct pointed to by
|
|
.Fa h
|
|
will be filled with the relevant data for the item.
|
|
The definition of
|
|
.Fa hid_item_t
|
|
can be found in
|
|
.Pa <libusbhid.h>
|
|
and the meaning of the components in the USB HID documentation.
|
|
.Pp
|
|
Data should be read/written to the device in the size of
|
|
the report. The size of a report (of a certain kind) can be
|
|
computed by the
|
|
.Fn hid_report_size
|
|
function.
|
|
.Pp
|
|
To locate a single item the
|
|
.Fn hid_locate
|
|
function can be used. It should be given the usage code of
|
|
the item and its kind and it will fill the item and return
|
|
non-zero if the item was found.
|
|
.Pp
|
|
.Ss NAME TRANSLATION FUNCTIONS
|
|
The function
|
|
.Fn hid_usage_page
|
|
will return the symbolic name of a usage page, and the function
|
|
.Fn hid_usage_in_page
|
|
will return the symbolic name of the usage within the page.
|
|
Both these functions may return a pointer to static data.
|
|
.Pp
|
|
The functions
|
|
.Fn hid_parse_usage_page
|
|
and
|
|
.Fn hid_parse_usage_in_page
|
|
are the inverses of
|
|
.Fn hid_usage_page
|
|
and
|
|
.Fn hid_usage_in_page .
|
|
They take a usage string and return the number of the usage, or -1
|
|
if it cannot be found.
|
|
.Pp
|
|
Before any of these functions can be called the usage table
|
|
must be parsed, this is done by calling
|
|
.Fn hid_init
|
|
with the name of the table. Passing
|
|
.Fa NULL
|
|
to this function will cause it to use the default table.
|
|
.Ss DATA EXTRACTION FUNCTIONS
|
|
Given the data obtained from a HID device and an item in the
|
|
report descriptor the
|
|
.Fn hid_get_data
|
|
function extracts the value of the item.
|
|
Conversely
|
|
.Fn hid_set_data
|
|
can be used to put data into a report (which must be zeroed first).
|
|
.Sh EXAMPLES
|
|
Not yet.
|
|
.Sh FILES
|
|
.Pa /usr/share/misc/usb_hid_usages
|
|
The default HID usage table.
|
|
.Sh BUGS
|
|
This man page is woefully incomplete.
|
|
.Sh SEE ALSO
|
|
The
|
|
.Tn USB
|
|
specifications can be found at
|
|
.Dv http://www.usb.org/developers/docs.htm .
|
|
.Pp
|
|
.Xr uhid 4 ,
|
|
.Xr usb 4
|
|
.Sh HISTORY
|
|
The
|
|
.Nm
|
|
library first appeared in
|
|
.Nx 1.5 .
|