drivers/gpu/drm/ttm/ttm_module.c

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