1/*
2 * Copyright (C) 2011 matt mooney <mfm@muteddisk.com>
3 *               2005-2007 Takahiro Hirofuchi
4 *
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
17 */
18
19#include <libudev.h>
20
21#include <errno.h>
22#include <stdio.h>
23#include <string.h>
24
25#include <getopt.h>
26
27#include "usbip_common.h"
28#include "utils.h"
29#include "usbip.h"
30#include "sysfs_utils.h"
31
32static const char usbip_unbind_usage_string[] =
33	"usbip unbind <args>\n"
34	"    -b, --busid=<busid>    Unbind " USBIP_HOST_DRV_NAME ".ko from "
35	"device on <busid>\n";
36
37void usbip_unbind_usage(void)
38{
39	printf("usage: %s", usbip_unbind_usage_string);
40}
41
42static int unbind_device(char *busid)
43{
44	char bus_type[] = "usb";
45	int rc, ret = -1;
46
47	char unbind_attr_name[] = "unbind";
48	char unbind_attr_path[SYSFS_PATH_MAX];
49	char rebind_attr_name[] = "rebind";
50	char rebind_attr_path[SYSFS_PATH_MAX];
51
52	struct udev *udev;
53	struct udev_device *dev;
54	const char *driver;
55
56	/* Create libudev context. */
57	udev = udev_new();
58
59	/* Check whether the device with this bus ID exists. */
60	dev = udev_device_new_from_subsystem_sysname(udev, "usb", busid);
61	if (!dev) {
62		err("device with the specified bus ID does not exist");
63		goto err_close_udev;
64	}
65
66	/* Check whether the device is using usbip-host driver. */
67	driver = udev_device_get_driver(dev);
68	if (!driver || strcmp(driver, "usbip-host")) {
69		err("device is not bound to usbip-host driver");
70		goto err_close_udev;
71	}
72
73	/* Unbind device from driver. */
74	snprintf(unbind_attr_path, sizeof(unbind_attr_path), "%s/%s/%s/%s/%s/%s",
75		 SYSFS_MNT_PATH, SYSFS_BUS_NAME, bus_type, SYSFS_DRIVERS_NAME,
76		 USBIP_HOST_DRV_NAME, unbind_attr_name);
77
78	rc = write_sysfs_attribute(unbind_attr_path, busid, strlen(busid));
79	if (rc < 0) {
80		err("error unbinding device %s from driver", busid);
81		goto err_close_udev;
82	}
83
84	/* Notify driver of unbind. */
85	rc = modify_match_busid(busid, 0);
86	if (rc < 0) {
87		err("unable to unbind device on %s", busid);
88		goto err_close_udev;
89	}
90
91	/* Trigger new probing. */
92	snprintf(rebind_attr_path, sizeof(unbind_attr_path), "%s/%s/%s/%s/%s/%s",
93			SYSFS_MNT_PATH, SYSFS_BUS_NAME, bus_type, SYSFS_DRIVERS_NAME,
94			USBIP_HOST_DRV_NAME, rebind_attr_name);
95
96	rc = write_sysfs_attribute(rebind_attr_path, busid, strlen(busid));
97	if (rc < 0) {
98		err("error rebinding");
99		goto err_close_udev;
100	}
101
102	ret = 0;
103	info("unbind device on busid %s: complete", busid);
104
105err_close_udev:
106	udev_device_unref(dev);
107	udev_unref(udev);
108
109	return ret;
110}
111
112int usbip_unbind(int argc, char *argv[])
113{
114	static const struct option opts[] = {
115		{ "busid", required_argument, NULL, 'b' },
116		{ NULL,    0,                 NULL,  0  }
117	};
118
119	int opt;
120	int ret = -1;
121
122	for (;;) {
123		opt = getopt_long(argc, argv, "b:", opts, NULL);
124
125		if (opt == -1)
126			break;
127
128		switch (opt) {
129		case 'b':
130			ret = unbind_device(optarg);
131			goto out;
132		default:
133			goto err_out;
134		}
135	}
136
137err_out:
138	usbip_unbind_usage();
139out:
140	return ret;
141}
142