1/* SPDX-License-Identifier: GPL-2.0 OR MIT */
2/**************************************************************************
3 *
4 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
5 * All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the
9 * "Software"), to deal in the Software without restriction, including
10 * without limitation the rights to use, copy, modify, merge, publish,
11 * distribute, sub license, and/or sell copies of the Software, and to
12 * permit persons to whom the Software is furnished to do so, subject to
13 * the following conditions:
14 *
15 * The above copyright notice and this permission notice (including the
16 * next paragraph) shall be included in all copies or substantial portions
17 * of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
22 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
23 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
24 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
25 * USE OR OTHER DEALINGS IN THE SOFTWARE.
26 *
27 **************************************************************************/
28/*
29 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
30 * 	    Jerome Glisse
31 */
32#include <linux/module.h>
33#include <linux/device.h>
34#include <linux/sched.h>
35#include <drm/ttm/ttm_module.h>
36#include <drm/drm_sysfs.h>
37
38static DECLARE_WAIT_QUEUE_HEAD(exit_q);
39static atomic_t device_released;
40
41static struct device_type ttm_drm_class_type = {
42	.name = "ttm",
43	/**
44	 * Add pm ops here.
45	 */
46};
47
48static void ttm_drm_class_device_release(struct device *dev)
49{
50	atomic_set(&device_released, 1);
51	wake_up_all(&exit_q);
52}
53
54static struct device ttm_drm_class_device = {
55	.type = &ttm_drm_class_type,
56	.release = &ttm_drm_class_device_release
57};
58
59struct kobject *ttm_get_kobj(void)
60{
61	struct kobject *kobj = &ttm_drm_class_device.kobj;
62	BUG_ON(kobj == NULL);
63	return kobj;
64}
65
66static int __init ttm_init(void)
67{
68	int ret;
69
70	ret = dev_set_name(&ttm_drm_class_device, "ttm");
71	if (unlikely(ret != 0))
72		return ret;
73
74	atomic_set(&device_released, 0);
75	ret = drm_class_device_register(&ttm_drm_class_device);
76	if (unlikely(ret != 0))
77		goto out_no_dev_reg;
78
79	return 0;
80out_no_dev_reg:
81	atomic_set(&device_released, 1);
82	wake_up_all(&exit_q);
83	return ret;
84}
85
86static void __exit ttm_exit(void)
87{
88	drm_class_device_unregister(&ttm_drm_class_device);
89
90	/**
91	 * Refuse to unload until the TTM device is released.
92	 * Not sure this is 100% needed.
93	 */
94
95	wait_event(exit_q, atomic_read(&device_released) == 1);
96}
97
98module_init(ttm_init);
99module_exit(ttm_exit);
100
101MODULE_AUTHOR("Thomas Hellstrom, Jerome Glisse");
102MODULE_DESCRIPTION("TTM memory manager subsystem (for DRM device)");
103MODULE_LICENSE("GPL and additional rights");
104