2 * Copyright (C) 2003-2008 Takahiro Hirofuchi
4 * This is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
20 #include "usbip_common.h"
21 #include <linux/kthread.h>
23 static int event_handler(struct usbip_device *ud)
25 usbip_dbg_eh("enter\n");
28 * Events are handled by only this thread.
30 while (usbip_event_happened(ud)) {
31 usbip_dbg_eh("pending event %lx\n", ud->event);
34 * NOTE: shutdown must come first.
35 * Shutdown the device.
37 if (ud->event & USBIP_EH_SHUTDOWN) {
38 ud->eh_ops.shutdown(ud);
40 ud->event &= ~USBIP_EH_SHUTDOWN;
45 /* Stop the error handler. */
46 if (ud->event & USBIP_EH_BYE)
49 /* Reset the device. */
50 if (ud->event & USBIP_EH_RESET) {
53 ud->event &= ~USBIP_EH_RESET;
58 /* Mark the device as unusable. */
59 if (ud->event & USBIP_EH_UNUSABLE) {
60 ud->eh_ops.unusable(ud);
62 ud->event &= ~USBIP_EH_UNUSABLE;
68 printk(KERN_ERR "%s: unknown event\n", __func__);
75 static void event_handler_loop(struct usbip_task *ut)
77 struct usbip_device *ud = container_of(ut, struct usbip_device, eh);
80 if (signal_pending(current)) {
81 usbip_dbg_eh("signal catched!\n");
85 if (event_handler(ud) < 0)
88 wait_event_interruptible(ud->eh_waitq,
89 usbip_event_happened(ud));
90 usbip_dbg_eh("wakeup\n");
94 int usbip_start_eh(struct usbip_device *ud)
96 struct usbip_task *eh = &ud->eh;
97 struct task_struct *th;
99 init_waitqueue_head(&ud->eh_waitq);
102 usbip_task_init(eh, "usbip_eh", event_handler_loop);
104 th = kthread_run(usbip_thread, (void *)eh, "usbip");
107 "Unable to start control thread\n");
111 wait_for_completion(&eh->thread_done);
114 EXPORT_SYMBOL_GPL(usbip_start_eh);
116 void usbip_stop_eh(struct usbip_device *ud)
118 struct usbip_task *eh = &ud->eh;
120 if (eh->thread == current)
121 return; /* do not wait for myself */
123 wait_for_completion(&eh->thread_done);
124 usbip_dbg_eh("usbip_eh has finished\n");
126 EXPORT_SYMBOL_GPL(usbip_stop_eh);
128 void usbip_event_add(struct usbip_device *ud, unsigned long event)
130 spin_lock(&ud->lock);
134 wake_up(&ud->eh_waitq);
136 spin_unlock(&ud->lock);
138 EXPORT_SYMBOL_GPL(usbip_event_add);
140 int usbip_event_happened(struct usbip_device *ud)
144 spin_lock(&ud->lock);
149 spin_unlock(&ud->lock);
153 EXPORT_SYMBOL_GPL(usbip_event_happened);