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:\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