1 .\" $NetBSD: usb.3,v 1.13 2000/09/24 02:17:52 augustss Exp $
3 .\" Copyright (c) 1999, 2001 Lennart Augustsson <augustss@NetBSD.org>
4 .\" All rights reserved.
6 .\" Redistribution and use in source and binary forms, with or without
7 .\" modification, are permitted provided that the following conditions
9 .\" 1. Redistributions of source code must retain the above copyright
10 .\" notice, this list of conditions and the following disclaimer.
11 .\" 2. Redistributions in binary form must reproduce the above copyright
12 .\" notice, this list of conditions and the following disclaimer in the
13 .\" documentation and/or other materials provided with the distribution.
15 .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 .Nm hid_get_report_desc ,
35 .Nm hid_get_report_id ,
36 .Nm hid_use_report_desc ,
37 .Nm hid_dispose_report_desc ,
44 .Nm hid_usage_in_page ,
48 .Nd USB HID access routines
54 .Fn hid_get_report_desc "int file"
56 .Fn hid_get_report_id "int file"
58 .Fn hid_set_immed "int fd" "int enable"
60 .Fn hid_use_report_desc "unsigned char *data" "unsigned int size"
62 .Fn hid_dispose_report_desc "report_desc_t d"
64 .Fn hid_start_parse "report_desc_t d" "int kindset" "int id"
66 .Fn hid_end_parse "hid_data_t s"
68 .Fn hid_get_item "hid_data_t s" "hid_item_t *h"
70 .Fn hid_report_size "report_desc_t d" "hid_kind_t k" "int id"
72 .Fn hid_locate "report_desc_t d" "u_int usage" "hid_kind_t k" "hid_item_t *h" "int id"
74 .Fn hid_usage_page "int i"
76 .Fn hid_usage_in_page "u_int u"
78 .Fn hid_parse_usage_page "const char *"
80 .Fn hid_parse_usage_in_page "const char *"
82 .Fn hid_init "const char *file"
84 .Fn hid_get_data "const void *data" "const hid_item_t *h"
86 .Fn hid_set_data "void *buf" "const hid_item_t *h" "int data"
90 library provides routines to extract data from USB Human Interface Devices.
92 USB HID devices send and receive data layed out in a device dependent way.
95 library contains routines to extract the
96 .Em "report descriptor"
97 which contains the data layout information and then use this information.
99 The routines can be divided into four parts: extraction of the descriptor,
100 parsing of the descriptor, translating to/from symbolic names, and
102 .Ss Synchronous HID operation
103 Synchronous HID operation can be enabled or disabled by a call to
105 If the second argument is zero synchronous HID operation is disabled.
106 Else synchronous HID operation is enabled.
107 The function returns a negative value on failure.
108 .Ss Descriptor Functions
109 The report descriptor ID can be obtained by calling
110 .Fn hid_get_report_id .
111 A report descriptor can be obtained by calling
112 .Fn hid_get_report_desc
113 with a file descriptor obtained by opening a
116 Alternatively a data buffer containing the report descriptor can be
118 .Fn hid_use_report_desc .
119 The data is copied into an internal structure.
120 When the report descriptor
121 is no longer needed it should be freed by calling
122 .Fn hid_dispose_report_desc .
125 is opaque and should be used when calling the parsing functions.
127 .Fn hid_dispose_report_desc
130 .Ss Descriptor Parsing Functions
131 To parse the report descriptor the
133 function should be called with a report descriptor and a set that
134 describes which items that are interesting.
135 The set is obtained by OR-ing together values
141 The report ID (if present) is given by
145 if the initialization fails, otherwise an opaque value to be used
149 function should be called to free internal data structures.
151 To iterate through all the items in the report descriptor
153 should be called while it returns a value greater than 0.
154 When the report descriptor ends it will returns 0; a syntax
155 error within the report descriptor will cause a return value less
157 The struct pointed to by
159 will be filled with the relevant data for the item.
164 and the meaning of the components in the USB HID documentation.
166 Data should be read/written to the device in the size of
168 The size of a report (of a certain kind) can be computed by the
171 If the report is prefixed by an ID byte it is given by
174 To locate a single item the
176 function can be used.
177 It should be given the usage code of
178 the item and its kind and it will fill the item and return
179 non-zero if the item was found.
180 .Ss Name Translation Functions
183 will return the symbolic name of a usage page, and the function
184 .Fn hid_usage_in_page
185 will return the symbolic name of the usage within the page.
186 Both these functions may return a pointer to static data.
189 .Fn hid_parse_usage_page
191 .Fn hid_parse_usage_in_page
195 .Fn hid_usage_in_page .
196 They take a usage string and return the number of the usage, or \-1
197 if it cannot be found.
199 Before any of these functions can be called the usage table
200 must be parsed, this is done by calling
202 with the name of the table.
205 to this function will cause it to use the default table.
206 .Ss Data Extraction Functions
207 Given the data obtained from a HID device and an item in the
208 report descriptor the
210 function extracts the value of the item.
213 can be used to put data into a report (which must be zeroed first).
215 .Bl -tag -width ".Pa /usr/share/misc/usb_hid_usages"
216 .It Pa /usr/share/misc/usb_hid_usages
217 The default HID usage table.
224 specifications can be found at
225 .Pa http://www.usb.org/developers/docs/ .
232 library first appeared in
235 This man page is woefully incomplete.