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 <linux/debugfs.h> 36 #include <drm/drm_sysfs.h> 37 38 #include "ttm_module.h" 39 40 static DECLARE_WAIT_QUEUE_HEAD(exit_q); 41 static atomic_t device_released; 42 struct dentry *ttm_debugfs_root; 43 44 static struct device_type ttm_drm_class_type = { 45 .name = "ttm", 46 /** 47 * Add pm ops here. 48 */ 49 }; 50 51 static void ttm_drm_class_device_release(struct device *dev) 52 { 53 atomic_set(&device_released, 1); 54 wake_up_all(&exit_q); 55 } 56 57 static struct device ttm_drm_class_device = { 58 .type = &ttm_drm_class_type, 59 .release = &ttm_drm_class_device_release 60 }; 61 62 struct kobject *ttm_get_kobj(void) 63 { 64 struct kobject *kobj = &ttm_drm_class_device.kobj; 65 BUG_ON(kobj == NULL); 66 return kobj; 67 } 68 69 static int __init ttm_init(void) 70 { 71 int ret; 72 73 ret = dev_set_name(&ttm_drm_class_device, "ttm"); 74 if (unlikely(ret != 0)) 75 return ret; 76 77 atomic_set(&device_released, 0); 78 ret = drm_class_device_register(&ttm_drm_class_device); 79 if (unlikely(ret != 0)) 80 goto out_no_dev_reg; 81 82 ttm_debugfs_root = debugfs_create_dir("ttm", NULL); 83 return 0; 84 out_no_dev_reg: 85 atomic_set(&device_released, 1); 86 wake_up_all(&exit_q); 87 return ret; 88 } 89 90 static void __exit ttm_exit(void) 91 { 92 drm_class_device_unregister(&ttm_drm_class_device); 93 94 /** 95 * Refuse to unload until the TTM device is released. 96 * Not sure this is 100% needed. 97 */ 98 99 wait_event(exit_q, atomic_read(&device_released) == 1); 100 debugfs_remove(ttm_debugfs_root); 101 } 102 103 module_init(ttm_init); 104 module_exit(ttm_exit); 105 106 MODULE_AUTHOR("Thomas Hellstrom, Jerome Glisse"); 107 MODULE_DESCRIPTION("TTM memory manager subsystem (for DRM device)"); 108 MODULE_LICENSE("GPL and additional rights"); 109