1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2011 matt mooney <mfm@muteddisk.com>
4 * 2005-2007 Takahiro Hirofuchi
5 */
6
7#include <libudev.h>
8
9#include <errno.h>
10#include <stdio.h>
11#include <string.h>
12
13#include <getopt.h>
14
15#include "usbip_common.h"
16#include "utils.h"
17#include "usbip.h"
18#include "sysfs_utils.h"
19
20static const char usbip_unbind_usage_string[] =
21 "usbip unbind <args>\n"
22 " -b, --busid=<busid> Unbind " USBIP_HOST_DRV_NAME ".ko from "
23 "device on <busid>\n";
24
25void usbip_unbind_usage(void)
26{
27 printf("usage: %s", usbip_unbind_usage_string);
28}
29
30static int unbind_device(char *busid)
31{
32 char bus_type[] = "usb";
33 int rc, ret = -1;
34
35 char unbind_attr_name[] = "unbind";
36 char unbind_attr_path[SYSFS_PATH_MAX];
37 char rebind_attr_name[] = "rebind";
38 char rebind_attr_path[SYSFS_PATH_MAX];
39
40 struct udev *udev;
41 struct udev_device *dev;
42 const char *driver;
43
44 /* Create libudev context. */
45 udev = udev_new();
46
47 /* Check whether the device with this bus ID exists. */
48 dev = udev_device_new_from_subsystem_sysname(udev, "usb", busid);
49 if (!dev) {
50 err("device with the specified bus ID does not exist");
51 goto err_close_udev;
52 }
53
54 /* Check whether the device is using usbip-host driver. */
55 driver = udev_device_get_driver(dev);
56 if (!driver || strcmp(driver, "usbip-host")) {
57 err("device is not bound to usbip-host driver");
58 goto err_close_udev;
59 }
60
61 /* Unbind device from driver. */
62 snprintf(unbind_attr_path, sizeof(unbind_attr_path), "%s/%s/%s/%s/%s/%s",
63 SYSFS_MNT_PATH, SYSFS_BUS_NAME, bus_type, SYSFS_DRIVERS_NAME,
64 USBIP_HOST_DRV_NAME, unbind_attr_name);
65
66 rc = write_sysfs_attribute(unbind_attr_path, busid, strlen(busid));
67 if (rc < 0) {
68 err("error unbinding device %s from driver", busid);
69 goto err_close_udev;
70 }
71
72 /* Notify driver of unbind. */
73 rc = modify_match_busid(busid, add: 0);
74 if (rc < 0) {
75 err("unable to unbind device on %s", busid);
76 goto err_close_udev;
77 }
78
79 /* Trigger new probing. */
80 snprintf(rebind_attr_path, sizeof(unbind_attr_path), "%s/%s/%s/%s/%s/%s",
81 SYSFS_MNT_PATH, SYSFS_BUS_NAME, bus_type, SYSFS_DRIVERS_NAME,
82 USBIP_HOST_DRV_NAME, rebind_attr_name);
83
84 rc = write_sysfs_attribute(rebind_attr_path, busid, strlen(busid));
85 if (rc < 0) {
86 err("error rebinding");
87 goto err_close_udev;
88 }
89
90 ret = 0;
91 info("unbind device on busid %s: complete", busid);
92
93err_close_udev:
94 udev_device_unref(dev);
95 udev_unref(udev);
96
97 return ret;
98}
99
100int usbip_unbind(int argc, char *argv[])
101{
102 static const struct option opts[] = {
103 { "busid", required_argument, NULL, 'b' },
104 { NULL, 0, NULL, 0 }
105 };
106
107 int opt;
108 int ret = -1;
109
110 for (;;) {
111 opt = getopt_long(argc, argv, "b:", opts, NULL);
112
113 if (opt == -1)
114 break;
115
116 switch (opt) {
117 case 'b':
118 ret = unbind_device(busid: optarg);
119 goto out;
120 default:
121 goto err_out;
122 }
123 }
124
125err_out:
126 usbip_unbind_usage();
127out:
128 return ret;
129}
130

source code of linux/tools/usb/usbip/src/usbip_unbind.c