tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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/drm_sysfs.h>
36
37#include "ttm_module.h"
38
39static DECLARE_WAIT_QUEUE_HEAD(exit_q);
40static atomic_t device_released;
41
42static struct device_type ttm_drm_class_type = {
43 .name = "ttm",
44 /**
45 * Add pm ops here.
46 */
47};
48
49static void ttm_drm_class_device_release(struct device *dev)
50{
51 atomic_set(&device_released, 1);
52 wake_up_all(&exit_q);
53}
54
55static struct device ttm_drm_class_device = {
56 .type = &ttm_drm_class_type,
57 .release = &ttm_drm_class_device_release
58};
59
60struct kobject *ttm_get_kobj(void)
61{
62 struct kobject *kobj = &ttm_drm_class_device.kobj;
63 BUG_ON(kobj == NULL);
64 return kobj;
65}
66
67static int __init ttm_init(void)
68{
69 int ret;
70
71 ret = dev_set_name(&ttm_drm_class_device, "ttm");
72 if (unlikely(ret != 0))
73 return ret;
74
75 atomic_set(&device_released, 0);
76 ret = drm_class_device_register(&ttm_drm_class_device);
77 if (unlikely(ret != 0))
78 goto out_no_dev_reg;
79
80 return 0;
81out_no_dev_reg:
82 atomic_set(&device_released, 1);
83 wake_up_all(&exit_q);
84 return ret;
85}
86
87static void __exit ttm_exit(void)
88{
89 drm_class_device_unregister(&ttm_drm_class_device);
90
91 /**
92 * Refuse to unload until the TTM device is released.
93 * Not sure this is 100% needed.
94 */
95
96 wait_event(exit_q, atomic_read(&device_released) == 1);
97}
98
99module_init(ttm_init);
100module_exit(ttm_exit);
101
102MODULE_AUTHOR("Thomas Hellstrom, Jerome Glisse");
103MODULE_DESCRIPTION("TTM memory manager subsystem (for DRM device)");
104MODULE_LICENSE("GPL and additional rights");