1 files changed, 129 insertions, 0 deletions
diff --git a/tools/usb/usbip/src/usbip_unbind.c b/tools/usb/usbip/src/usbip_unbind.c
new file mode 100644
index 000000000..66a44d4a0
--- /dev/null
+++ b/tools/usb/usbip/src/usbip_unbind.c
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2011 matt mooney <mfm@muteddisk.com>
+ *               2005-2007 Takahiro Hirofuchi
+ */
+
+#include <libudev.h>
+
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <getopt.h>
+
+#include "usbip_common.h"
+#include "utils.h"
+#include "usbip.h"
+#include "sysfs_utils.h"
+
+static const char usbip_unbind_usage_string[] =
+	"usbip unbind <args>\n"
+	"    -b, --busid=<busid>    Unbind " USBIP_HOST_DRV_NAME ".ko from "
+	"device on <busid>\n";
+
+void usbip_unbind_usage(void)
+{
+	printf("usage: %s", usbip_unbind_usage_string);
+}
+
+static int unbind_device(char *busid)
+{
+	char bus_type[] = "usb";
+	int rc, ret = -1;
+
+	char unbind_attr_name[] = "unbind";
+	char unbind_attr_path[SYSFS_PATH_MAX];
+	char rebind_attr_name[] = "rebind";
+	char rebind_attr_path[SYSFS_PATH_MAX];
+
+	struct udev *udev;
+	struct udev_device *dev;
+	const char *driver;
+
+	/* Create libudev context. */
+	udev = udev_new();
+
+	/* Check whether the device with this bus ID exists. */
+	dev = udev_device_new_from_subsystem_sysname(udev, "usb", busid);
+	if (!dev) {
+		err("device with the specified bus ID does not exist");
+		goto err_close_udev;
+	}
+
+	/* Check whether the device is using usbip-host driver. */
+	driver = udev_device_get_driver(dev);
+	if (!driver || strcmp(driver, "usbip-host")) {
+		err("device is not bound to usbip-host driver");
+		goto err_close_udev;
+	}
+
+	/* Unbind device from driver. */
+	snprintf(unbind_attr_path, sizeof(unbind_attr_path), "%s/%s/%s/%s/%s/%s",
+		 SYSFS_MNT_PATH, SYSFS_BUS_NAME, bus_type, SYSFS_DRIVERS_NAME,
+		 USBIP_HOST_DRV_NAME, unbind_attr_name);
+
+	rc = write_sysfs_attribute(unbind_attr_path, busid, strlen(busid));
+	if (rc < 0) {
+		err("error unbinding device %s from driver", busid);
+		goto err_close_udev;
+	}
+
+	/* Notify driver of unbind. */
+	rc = modify_match_busid(busid, 0);
+	if (rc < 0) {
+		err("unable to unbind device on %s", busid);
+		goto err_close_udev;
+	}
+
+	/* Trigger new probing. */
+	snprintf(rebind_attr_path, sizeof(unbind_attr_path), "%s/%s/%s/%s/%s/%s",
+			SYSFS_MNT_PATH, SYSFS_BUS_NAME, bus_type, SYSFS_DRIVERS_NAME,
+			USBIP_HOST_DRV_NAME, rebind_attr_name);
+
+	rc = write_sysfs_attribute(rebind_attr_path, busid, strlen(busid));
+	if (rc < 0) {
+		err("error rebinding");
+		goto err_close_udev;
+	}
+
+	ret = 0;
+	info("unbind device on busid %s: complete", busid);
+
+err_close_udev:
+	udev_device_unref(dev);
+	udev_unref(udev);
+
+	return ret;
+}
+
+int usbip_unbind(int argc, char *argv[])
+{
+	static const struct option opts[] = {
+		{ "busid", required_argument, NULL, 'b' },
+		{ NULL,    0,                 NULL,  0  }
+	};
+
+	int opt;
+	int ret = -1;
+
+	for (;;) {
+		opt = getopt_long(argc, argv, "b:", opts, NULL);
+
+		if (opt == -1)
+			break;
+
+		switch (opt) {
+		case 'b':
+			ret = unbind_device(optarg);
+			goto out;
+		default:
+			goto err_out;
+		}
+	}
+
+err_out:
+	usbip_unbind_usage();
+out:
+	return ret;
+}