1// SPDX-License-Identifier: GPL-2.0
2
3/*
4 * video_device_test - Video Device Test
5 *
6 * Copyright (c) 2016 Shuah Khan <shuahkh@osg.samsung.com>
7 * Copyright (c) 2016 Samsung Electronics Co., Ltd.
8 *
9 */
10
11/*
12 * This file adds a test for Video Device. This test should not be included
13 * in the Kselftest run. This test should be run when hardware and driver
14 * that makes use of V4L2 API is present.
15 *
16 * This test opens user specified Video Device and calls video ioctls in a
17 * loop once every 10 seconds.
18 *
19 * Usage:
20 * sudo ./video_device_test -d /dev/videoX
21 *
22 * While test is running, remove the device or unbind the driver and
23 * ensure there are no use after free errors and other Oops in the
24 * dmesg.
25 * When possible, enable KaSan kernel config option for use-after-free
26 * error detection.
27*/
28
29#include <stdio.h>
30#include <unistd.h>
31#include <stdlib.h>
32#include <errno.h>
33#include <string.h>
34#include <fcntl.h>
35#include <sys/ioctl.h>
36#include <sys/stat.h>
37#include <time.h>
38#include <linux/videodev2.h>
39
40#define PRIORITY_MAX 4
41
42int priority_test(int fd)
43{
44 /* This test will try to update the priority associated with a file descriptor */
45
46 enum v4l2_priority old_priority, new_priority, priority_to_compare;
47 int ret;
48 int result = 0;
49
50 ret = ioctl(fd, VIDIOC_G_PRIORITY, &old_priority);
51 if (ret < 0) {
52 printf("Failed to get priority: %s\n", strerror(errno));
53 return -1;
54 }
55 new_priority = (old_priority + 1) % PRIORITY_MAX;
56 ret = ioctl(fd, VIDIOC_S_PRIORITY, &new_priority);
57 if (ret < 0) {
58 printf("Failed to set priority: %s\n", strerror(errno));
59 return -1;
60 }
61 ret = ioctl(fd, VIDIOC_G_PRIORITY, &priority_to_compare);
62 if (ret < 0) {
63 printf("Failed to get new priority: %s\n", strerror(errno));
64 result = -1;
65 goto cleanup;
66 }
67 if (priority_to_compare != new_priority) {
68 printf("Priority wasn't set - test failed\n");
69 result = -1;
70 }
71
72cleanup:
73 ret = ioctl(fd, VIDIOC_S_PRIORITY, &old_priority);
74 if (ret < 0) {
75 printf("Failed to restore priority: %s\n", strerror(errno));
76 return -1;
77 }
78 return result;
79}
80
81int loop_test(int fd)
82{
83 int count;
84 struct v4l2_tuner vtuner;
85 struct v4l2_capability vcap;
86 int ret;
87
88 /* Generate random number of interations */
89 srand((unsigned int) time(NULL));
90 count = rand();
91
92 printf("\nNote:\n"
93 "While test is running, remove the device or unbind\n"
94 "driver and ensure there are no use after free errors\n"
95 "and other Oops in the dmesg. When possible, enable KaSan\n"
96 "kernel config option for use-after-free error detection.\n\n");
97
98 while (count > 0) {
99 ret = ioctl(fd, VIDIOC_QUERYCAP, &vcap);
100 if (ret < 0)
101 printf("VIDIOC_QUERYCAP errno %s\n", strerror(errno));
102 else
103 printf("Video device driver %s\n", vcap.driver);
104
105 ret = ioctl(fd, VIDIOC_G_TUNER, &vtuner);
106 if (ret < 0)
107 printf("VIDIOC_G_TUNER, errno %s\n", strerror(errno));
108 else
109 printf("type %d rangelow %d rangehigh %d\n",
110 vtuner.type, vtuner.rangelow, vtuner.rangehigh);
111 sleep(10);
112 count--;
113 }
114 return 0;
115}
116
117int main(int argc, char **argv)
118{
119 int opt;
120 char video_dev[256];
121 int fd;
122 int test_result;
123
124 if (argc < 2) {
125 printf("Usage: %s [-d </dev/videoX>]\n", argv[0]);
126 exit(-1);
127 }
128
129 /* Process arguments */
130 while ((opt = getopt(argc, argv, "d:")) != -1) {
131 switch (opt) {
132 case 'd':
133 strncpy(video_dev, optarg, sizeof(video_dev) - 1);
134 video_dev[sizeof(video_dev)-1] = '\0';
135 break;
136 default:
137 printf("Usage: %s [-d </dev/videoX>]\n", argv[0]);
138 exit(-1);
139 }
140 }
141
142 /* Open Video device and keep it open */
143 fd = open(video_dev, O_RDWR);
144 if (fd == -1) {
145 printf("Video Device open errno %s\n", strerror(errno));
146 exit(-1);
147 }
148
149 test_result = priority_test(fd);
150 if (!test_result)
151 printf("Priority test - PASSED\n");
152 else
153 printf("Priority test - FAILED\n");
154
155 loop_test(fd);
156}
157

source code of linux/tools/testing/selftests/media_tests/video_device_test.c