swh:1:snp:173f8deb0c56c557784b4fd217e7608ac6197844
Tip revision: 9f4ad9e425a1d3b6a34617b8ea226d56a119a717 authored by Linus Torvalds on 25 April 2021, 20:49:08 UTC
Linux 5.12
Linux 5.12
Tip revision: 9f4ad9e
ttm_module.c
/* SPDX-License-Identifier: GPL-2.0 OR MIT */
/**************************************************************************
*
* Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
* USE OR OTHER DEALINGS IN THE SOFTWARE.
*
**************************************************************************/
/*
* Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
* Jerome Glisse
*/
#include <linux/module.h>
#include <linux/device.h>
#include <linux/sched.h>
#include <drm/drm_sysfs.h>
#include "ttm_module.h"
static DECLARE_WAIT_QUEUE_HEAD(exit_q);
static atomic_t device_released;
static struct device_type ttm_drm_class_type = {
.name = "ttm",
/**
* Add pm ops here.
*/
};
static void ttm_drm_class_device_release(struct device *dev)
{
atomic_set(&device_released, 1);
wake_up_all(&exit_q);
}
static struct device ttm_drm_class_device = {
.type = &ttm_drm_class_type,
.release = &ttm_drm_class_device_release
};
struct kobject *ttm_get_kobj(void)
{
struct kobject *kobj = &ttm_drm_class_device.kobj;
BUG_ON(kobj == NULL);
return kobj;
}
static int __init ttm_init(void)
{
int ret;
ret = dev_set_name(&ttm_drm_class_device, "ttm");
if (unlikely(ret != 0))
return ret;
atomic_set(&device_released, 0);
ret = drm_class_device_register(&ttm_drm_class_device);
if (unlikely(ret != 0))
goto out_no_dev_reg;
return 0;
out_no_dev_reg:
atomic_set(&device_released, 1);
wake_up_all(&exit_q);
return ret;
}
static void __exit ttm_exit(void)
{
drm_class_device_unregister(&ttm_drm_class_device);
/**
* Refuse to unload until the TTM device is released.
* Not sure this is 100% needed.
*/
wait_event(exit_q, atomic_read(&device_released) == 1);
}
module_init(ttm_init);
module_exit(ttm_exit);
MODULE_AUTHOR("Thomas Hellstrom, Jerome Glisse");
MODULE_DESCRIPTION("TTM memory manager subsystem (for DRM device)");
MODULE_LICENSE("GPL and additional rights");