1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Hidraw Userspace Example
4 *
5 * Copyright (c) 2010 Alan Ott <alan@signal11.us>
6 * Copyright (c) 2010 Signal 11 Software
7 *
8 * The code may be used by anyone for any purpose,
9 * and can serve as a starting point for developing
10 * applications using hidraw.
11 */
12
13/* Linux */
14#include <linux/types.h>
15#include <linux/input.h>
16#include <linux/hidraw.h>
17
18/*
19 * Ugly hack to work around failing compilation on systems that don't
20 * yet populate new version of hidraw.h to userspace.
21 */
22#ifndef HIDIOCSFEATURE
23#warning Please have your distro update the userspace kernel headers
24#define HIDIOCSFEATURE(len) _IOC(_IOC_WRITE|_IOC_READ, 'H', 0x06, len)
25#define HIDIOCGFEATURE(len) _IOC(_IOC_WRITE|_IOC_READ, 'H', 0x07, len)
26#endif
27
28/* Unix */
29#include <sys/ioctl.h>
30#include <sys/types.h>
31#include <sys/stat.h>
32#include <fcntl.h>
33#include <unistd.h>
34
35/* C */
36#include <stdio.h>
37#include <string.h>
38#include <stdlib.h>
39#include <errno.h>
40
41const char *bus_str(int bus);
42
43int main(int argc, char **argv)
44{
45 int fd;
46 int i, res, desc_size = 0;
47 char buf[256];
48 struct hidraw_report_descriptor rpt_desc;
49 struct hidraw_devinfo info;
50 char *device = "/dev/hidraw0";
51
52 if (argc > 1)
53 device = argv[1];
54
55 /* Open the Device with non-blocking reads. In real life,
56 don't use a hard coded path; use libudev instead. */
57 fd = open(device, O_RDWR|O_NONBLOCK);
58
59 if (fd < 0) {
60 perror("Unable to open device");
61 return 1;
62 }
63
64 memset(&rpt_desc, 0x0, sizeof(rpt_desc));
65 memset(&info, 0x0, sizeof(info));
66 memset(buf, 0x0, sizeof(buf));
67
68 /* Get Report Descriptor Size */
69 res = ioctl(fd, HIDIOCGRDESCSIZE, &desc_size);
70 if (res < 0)
71 perror("HIDIOCGRDESCSIZE");
72 else
73 printf("Report Descriptor Size: %d\n", desc_size);
74
75 /* Get Report Descriptor */
76 rpt_desc.size = desc_size;
77 res = ioctl(fd, HIDIOCGRDESC, &rpt_desc);
78 if (res < 0) {
79 perror("HIDIOCGRDESC");
80 } else {
81 printf("Report Descriptor:\n");
82 for (i = 0; i < rpt_desc.size; i++)
83 printf("%hhx ", rpt_desc.value[i]);
84 puts("\n");
85 }
86
87 /* Get Raw Name */
88 res = ioctl(fd, HIDIOCGRAWNAME(256), buf);
89 if (res < 0)
90 perror("HIDIOCGRAWNAME");
91 else
92 printf("Raw Name: %s\n", buf);
93
94 /* Get Physical Location */
95 res = ioctl(fd, HIDIOCGRAWPHYS(256), buf);
96 if (res < 0)
97 perror("HIDIOCGRAWPHYS");
98 else
99 printf("Raw Phys: %s\n", buf);
100
101 /* Get Raw Info */
102 res = ioctl(fd, HIDIOCGRAWINFO, &info);
103 if (res < 0) {
104 perror("HIDIOCGRAWINFO");
105 } else {
106 printf("Raw Info:\n");
107 printf("\tbustype: %d (%s)\n",
108 info.bustype, bus_str(info.bustype));
109 printf("\tvendor: 0x%04hx\n", info.vendor);
110 printf("\tproduct: 0x%04hx\n", info.product);
111 }
112
113 /* Set Feature */
114 buf[0] = 0x9; /* Report Number */
115 buf[1] = 0xff;
116 buf[2] = 0xff;
117 buf[3] = 0xff;
118 res = ioctl(fd, HIDIOCSFEATURE(4), buf);
119 if (res < 0)
120 perror("HIDIOCSFEATURE");
121 else
122 printf("ioctl HIDIOCSFEATURE returned: %d\n", res);
123
124 /* Get Feature */
125 buf[0] = 0x9; /* Report Number */
126 res = ioctl(fd, HIDIOCGFEATURE(256), buf);
127 if (res < 0) {
128 perror("HIDIOCGFEATURE");
129 } else {
130 printf("ioctl HIDIOCGFEATURE returned: %d\n", res);
131 printf("Report data (not containing the report number):\n\t");
132 for (i = 0; i < res; i++)
133 printf("%hhx ", buf[i]);
134 puts("\n");
135 }
136
137 /* Send a Report to the Device */
138 buf[0] = 0x1; /* Report Number */
139 buf[1] = 0x77;
140 res = write(fd, buf, 2);
141 if (res < 0) {
142 printf("Error: %d\n", errno);
143 perror("write");
144 } else {
145 printf("write() wrote %d bytes\n", res);
146 }
147
148 /* Get a report from the device */
149 res = read(fd, buf, 16);
150 if (res < 0) {
151 perror("read");
152 } else {
153 printf("read() read %d bytes:\n\t", res);
154 for (i = 0; i < res; i++)
155 printf("%hhx ", buf[i]);
156 puts("\n");
157 }
158 close(fd);
159 return 0;
160}
161
162const char *
163bus_str(int bus)
164{
165 switch (bus) {
166 case BUS_USB:
167 return "USB";
168 break;
169 case BUS_HIL:
170 return "HIL";
171 break;
172 case BUS_BLUETOOTH:
173 return "Bluetooth";
174 break;
175 case BUS_VIRTUAL:
176 return "Virtual";
177 break;
178 default:
179 return "Other";
180 break;
181 }
182}
183