xref: /freebsd/lib/libusbhid/data.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*	$NetBSD: data.c,v 1.8 2000/04/02 11:10:53 augustss Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-2-Clause-NetBSD
5  *
6  * Copyright (c) 1999 Lennart Augustsson <augustss@netbsd.org>
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <sys/param.h>
35 #include <assert.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <dev/usb/usb_ioctl.h>
39 #include "usbhid.h"
40 #include "usbvar.h"
41 
42 int32_t
43 hid_get_data(const void *p, const hid_item_t *h)
44 {
45 	const uint8_t *buf;
46 	uint32_t hpos;
47 	uint32_t hsize;
48 	uint32_t data;
49 	int i, end, offs;
50 
51 	buf = p;
52 
53 	/* Skip report ID byte. */
54 	if (h->report_ID > 0)
55 		buf++;
56 
57 	hpos = h->pos;			/* bit position of data */
58 	hsize = h->report_size;		/* bit length of data */
59 
60 	/* Range check and limit */
61 	if (hsize == 0)
62 		return (0);
63 	if (hsize > 32)
64 		hsize = 32;
65 
66 	offs = hpos / 8;
67 	end = (hpos + hsize) / 8 - offs;
68 	data = 0;
69 	for (i = 0; i <= end; i++)
70 		data |= buf[offs + i] << (i*8);
71 
72 	/* Correctly shift down data */
73 	data >>= hpos % 8;
74 	hsize = 32 - hsize;
75 
76 	/* Mask and sign extend in one */
77 	if ((h->logical_minimum < 0) || (h->logical_maximum < 0))
78 		data = (int32_t)((int32_t)data << hsize) >> hsize;
79 	else
80 		data = (uint32_t)((uint32_t)data << hsize) >> hsize;
81 
82 	return (data);
83 }
84 
85 void
86 hid_set_data(void *p, const hid_item_t *h, int32_t data)
87 {
88 	uint8_t *buf;
89 	uint32_t hpos;
90 	uint32_t hsize;
91 	uint32_t mask;
92 	int i;
93 	int end;
94 	int offs;
95 
96 	buf = p;
97 
98 	/* Set report ID byte. */
99 	if (h->report_ID > 0)
100 		*buf++ = h->report_ID & 0xff;
101 
102 	hpos = h->pos;			/* bit position of data */
103 	hsize = h->report_size;		/* bit length of data */
104 
105 	if (hsize != 32) {
106 		mask = (1 << hsize) - 1;
107 		data &= mask;
108 	} else
109 		mask = ~0;
110 
111 	data <<= (hpos % 8);
112 	mask <<= (hpos % 8);
113 	mask = ~mask;
114 
115 	offs = hpos / 8;
116 	end = (hpos + hsize) / 8 - offs;
117 
118 	for (i = 0; i <= end; i++)
119 		buf[offs + i] = (buf[offs + i] & (mask >> (i*8))) |
120 		    ((data >> (i*8)) & 0xff);
121 }
122 
123 int
124 hid_get_report(int fd, enum hid_kind k, unsigned char *data, unsigned int size)
125 {
126 	struct usb_gen_descriptor ugd;
127 
128 	memset(&ugd, 0, sizeof(ugd));
129 	ugd.ugd_data = hid_pass_ptr(data);
130 	ugd.ugd_maxlen = size;
131 	ugd.ugd_report_type = k + 1;
132 	return (ioctl(fd, USB_GET_REPORT, &ugd));
133 }
134 
135 int
136 hid_set_report(int fd, enum hid_kind k, unsigned char *data, unsigned int size)
137 {
138 	struct usb_gen_descriptor ugd;
139 
140 	memset(&ugd, 0, sizeof(ugd));
141 	ugd.ugd_data = hid_pass_ptr(data);
142 	ugd.ugd_maxlen = size;
143 	ugd.ugd_report_type = k + 1;
144 	return (ioctl(fd, USB_SET_REPORT, &ugd));
145 }
146