// SPDX-License-Identifier: GPL-2.0
/*
* Hidraw Userspace Example
*
* Copyright (c) 2010 Alan Ott <alan@signal11.us>
* Copyright (c) 2010 Signal 11 Software
*
* The code may be used by anyone for any purpose,
* and can serve as a starting point for developing
* applications using hidraw.
*/
/* Linux */
#include <linux/types.h>
#include <linux/input.h>
#include <linux/hidraw.h>
/*
* Ugly hack to work around failing compilation on systems that don't
* yet populate new version of hidraw.h to userspace.
*/
#ifndef HIDIOCSFEATURE
#warning Please have your distro update the userspace kernel headers
#define HIDIOCSFEATURE(len) _IOC(_IOC_WRITE|_IOC_READ, 'H', 0x06, len)
#define HIDIOCGFEATURE(len) _IOC(_IOC_WRITE|_IOC_READ, 'H', 0x07, len)
#endif
/* Unix */
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
/* C */
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
const char *bus_str(int bus);
int main(int argc, char **argv)
{
int fd;
int i, res, desc_size = 0;
char buf[256];
struct hidraw_report_descriptor rpt_desc;
struct hidraw_devinfo info;
char *device = "/dev/hidraw0";
if (argc > 1)
device = argv[1];
/* Open the Device with non-blocking reads. In real life,
don't use a hard coded path; use libudev instead. */
fd = open(device, O_RDWR|O_NONBLOCK);
if (fd < 0) {
perror("Unable to open device");
return 1;
}
memset(&rpt_desc, 0x0, sizeof(rpt_desc));
memset(&info, 0x0, sizeof(info));
memset(buf, 0x0, sizeof(buf));
/* Get Report Descriptor Size */
res = ioctl(fd, HIDIOCGRDESCSIZE, &desc_size);
if (res < 0)
perror("HIDIOCGRDESCSIZE");
else
printf("Report Descriptor Size: %d\n", desc_size);
/* Get Report Descriptor */
rpt_desc.size = desc_size;
res = ioctl(fd, HIDIOCGRDESC, &rpt_desc);
if (res < 0) {
perror("HIDIOCGRDESC");
} else {
printf("Report Descriptor:\n");
for (i = 0; i < rpt_desc.size; i++)
printf("%hhx ", rpt_desc.value[i]);
puts("\n");
}
/* Get Raw Name */
res = ioctl(fd, HIDIOCGRAWNAME(256), buf);
if (res < 0)
perror("HIDIOCGRAWNAME");
else
printf("Raw Name: %s\n", buf);
/* Get Physical Location */
res = ioctl(fd, HIDIOCGRAWPHYS(256), buf);
if (res < 0)
perror("HIDIOCGRAWPHYS");
else
printf("Raw Phys: %s\n", buf);
/* Get Raw Info */
res = ioctl(fd, HIDIOCGRAWINFO, &info);
if (res < 0) {
perror("HIDIOCGRAWINFO");
} else {
printf("Raw Info:\n");
printf("\tbustype: %d (%s)\n",
info.bustype, bus_str(info.bustype));
printf("\tvendor: 0x%04hx\n", info.vendor);
printf("\tproduct: 0x%04hx\n", info.product);
}
/* Set Feature */
buf[0] = 0x9; /* Report Number */
buf[1] = 0xff;
buf[2] = 0xff;
buf[3] = 0xff;
res = ioctl(fd, HIDIOCSFEATURE(4), buf);
if (res < 0)
perror("HIDIOCSFEATURE");
else
printf("ioctl HIDIOCSFEATURE returned: %d\n", res);
/* Get Feature */
buf[0] = 0x9; /* Report Number */
res = ioctl(fd, HIDIOCGFEATURE(256), buf);
if (res < 0) {
perror("HIDIOCGFEATURE");
} else {
printf("ioctl HIDIOCGFEATURE returned: %d\n", res);
printf("Report data (not containing the report number):\n\t");
for (i = 0; i < res; i++)
printf("%hhx ", buf[i]);
puts("\n");
}
/* Send a Report to the Device */
buf[0] = 0x1; /* Report Number */
buf[1] = 0x77;
res = write(fd, buf, 2);
if (res < 0) {
printf("Error: %d\n", errno);
perror("write");
} else {
printf("write() wrote %d bytes\n", res);
}
/* Get a report from the device */
res = read(fd, buf, 16);
if (res < 0) {
perror("read");
} else {
printf("read() read %d bytes:\n\t", res);
for (i = 0; i < res; i++)
printf("%hhx ", buf[i]);
puts("\n");
}
close(fd);
return 0;
}
const char *
bus_str(int bus)
{
switch (bus) {
case BUS_USB:
return "USB";
break;
case BUS_HIL:
return "HIL";
break;
case BUS_BLUETOOTH:
return "Bluetooth";
break;
case BUS_VIRTUAL:
return "Virtual";
break;
default:
return "Other";
break;
}
}
