2 * Created: Fri Jan 19 10:48:35 2001 by faith@acm.org
4 * Copyright 2001 VA Linux Systems, Inc., Sunnyvale, California.
7 * Author Rickard E. (Rik) Faith <faith@valinux.com>
9 * Permission is hereby granted, free of charge, to any person obtaining a
10 * copy of this software and associated documentation files (the "Software"),
11 * to deal in the Software without restriction, including without limitation
12 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
13 * and/or sell copies of the Software, and to permit persons to whom the
14 * Software is furnished to do so, subject to the following conditions:
16 * The above copyright notice and this permission notice (including the next
17 * paragraph) shall be included in all copies or substantial portions of the
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
23 * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
24 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
25 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
26 * DEALINGS IN THE SOFTWARE.
29 #include <linux/debugfs.h>
31 #include <linux/module.h>
32 #include <linux/moduleparam.h>
33 #include <linux/mount.h>
34 #include <linux/slab.h>
36 #include <drm/drm_core.h>
37 #include "drm_crtc_internal.h"
38 #include "drm_legacy.h"
39 #include "drm_internal.h"
40 #include "drm_crtc_internal.h"
43 * drm_debug: Enable debug output.
44 * Bitmask of DRM_UT_x. See include/drm/drmP.h for details.
46 unsigned int drm_debug
= 0;
47 EXPORT_SYMBOL(drm_debug
);
49 MODULE_AUTHOR(CORE_AUTHOR
);
50 MODULE_DESCRIPTION(CORE_DESC
);
51 MODULE_LICENSE("GPL and additional rights");
52 MODULE_PARM_DESC(debug
, "Enable debug output, where each bit enables a debug category.\n"
53 "\t\tBit 0 (0x01) will enable CORE messages (drm core code)\n"
54 "\t\tBit 1 (0x02) will enable DRIVER messages (drm controller code)\n"
55 "\t\tBit 2 (0x04) will enable KMS messages (modesetting code)\n"
56 "\t\tBit 3 (0x08) will enable PRIME messages (prime code)\n"
57 "\t\tBit 4 (0x10) will enable ATOMIC messages (atomic code)\n"
58 "\t\tBit 5 (0x20) will enable VBL messages (vblank code)");
59 module_param_named(debug
, drm_debug
, int, 0600);
61 static DEFINE_SPINLOCK(drm_minor_lock
);
62 static struct idr drm_minors_idr
;
64 static struct dentry
*drm_debugfs_root
;
66 void drm_err(const char *format
, ...)
71 va_start(args
, format
);
76 printk(KERN_ERR
"[" DRM_NAME
":%ps] *ERROR* %pV",
77 __builtin_return_address(0), &vaf
);
81 EXPORT_SYMBOL(drm_err
);
83 void drm_ut_debug_printk(const char *function_name
, const char *format
, ...)
88 va_start(args
, format
);
92 printk(KERN_DEBUG
"[" DRM_NAME
":%s] %pV", function_name
, &vaf
);
96 EXPORT_SYMBOL(drm_ut_debug_printk
);
100 * A DRM device can provide several char-dev interfaces on the DRM-Major. Each
101 * of them is represented by a drm_minor object. Depending on the capabilities
102 * of the device-driver, different interfaces are registered.
104 * Minors can be accessed via dev->$minor_name. This pointer is either
105 * NULL or a valid drm_minor pointer and stays valid as long as the device is
106 * valid. This means, DRM minors have the same life-time as the underlying
107 * device. However, this doesn't mean that the minor is active. Minors are
108 * registered and unregistered dynamically according to device-state.
111 static struct drm_minor
**drm_minor_get_slot(struct drm_device
*dev
,
115 case DRM_MINOR_LEGACY
:
116 return &dev
->primary
;
117 case DRM_MINOR_RENDER
:
119 case DRM_MINOR_CONTROL
:
120 return &dev
->control
;
126 static int drm_minor_alloc(struct drm_device
*dev
, unsigned int type
)
128 struct drm_minor
*minor
;
132 minor
= kzalloc(sizeof(*minor
), GFP_KERNEL
);
139 idr_preload(GFP_KERNEL
);
140 spin_lock_irqsave(&drm_minor_lock
, flags
);
141 r
= idr_alloc(&drm_minors_idr
,
146 spin_unlock_irqrestore(&drm_minor_lock
, flags
);
154 minor
->kdev
= drm_sysfs_minor_alloc(minor
);
155 if (IS_ERR(minor
->kdev
)) {
156 r
= PTR_ERR(minor
->kdev
);
160 *drm_minor_get_slot(dev
, type
) = minor
;
164 spin_lock_irqsave(&drm_minor_lock
, flags
);
165 idr_remove(&drm_minors_idr
, minor
->index
);
166 spin_unlock_irqrestore(&drm_minor_lock
, flags
);
172 static void drm_minor_free(struct drm_device
*dev
, unsigned int type
)
174 struct drm_minor
**slot
, *minor
;
177 slot
= drm_minor_get_slot(dev
, type
);
182 put_device(minor
->kdev
);
184 spin_lock_irqsave(&drm_minor_lock
, flags
);
185 idr_remove(&drm_minors_idr
, minor
->index
);
186 spin_unlock_irqrestore(&drm_minor_lock
, flags
);
192 static int drm_minor_register(struct drm_device
*dev
, unsigned int type
)
194 struct drm_minor
*minor
;
200 minor
= *drm_minor_get_slot(dev
, type
);
204 ret
= drm_debugfs_init(minor
, minor
->index
, drm_debugfs_root
);
206 DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n");
210 ret
= device_add(minor
->kdev
);
214 /* replace NULL with @minor so lookups will succeed from now on */
215 spin_lock_irqsave(&drm_minor_lock
, flags
);
216 idr_replace(&drm_minors_idr
, minor
, minor
->index
);
217 spin_unlock_irqrestore(&drm_minor_lock
, flags
);
219 DRM_DEBUG("new minor registered %d\n", minor
->index
);
223 drm_debugfs_cleanup(minor
);
227 static void drm_minor_unregister(struct drm_device
*dev
, unsigned int type
)
229 struct drm_minor
*minor
;
232 minor
= *drm_minor_get_slot(dev
, type
);
233 if (!minor
|| !device_is_registered(minor
->kdev
))
236 /* replace @minor with NULL so lookups will fail from now on */
237 spin_lock_irqsave(&drm_minor_lock
, flags
);
238 idr_replace(&drm_minors_idr
, NULL
, minor
->index
);
239 spin_unlock_irqrestore(&drm_minor_lock
, flags
);
241 device_del(minor
->kdev
);
242 dev_set_drvdata(minor
->kdev
, NULL
); /* safety belt */
243 drm_debugfs_cleanup(minor
);
247 * drm_minor_acquire - Acquire a DRM minor
248 * @minor_id: Minor ID of the DRM-minor
250 * Looks up the given minor-ID and returns the respective DRM-minor object. The
251 * refence-count of the underlying device is increased so you must release this
252 * object with drm_minor_release().
254 * As long as you hold this minor, it is guaranteed that the object and the
255 * minor->dev pointer will stay valid! However, the device may get unplugged and
256 * unregistered while you hold the minor.
259 * Pointer to minor-object with increased device-refcount, or PTR_ERR on
262 struct drm_minor
*drm_minor_acquire(unsigned int minor_id
)
264 struct drm_minor
*minor
;
267 spin_lock_irqsave(&drm_minor_lock
, flags
);
268 minor
= idr_find(&drm_minors_idr
, minor_id
);
270 drm_dev_ref(minor
->dev
);
271 spin_unlock_irqrestore(&drm_minor_lock
, flags
);
274 return ERR_PTR(-ENODEV
);
275 } else if (drm_device_is_unplugged(minor
->dev
)) {
276 drm_dev_unref(minor
->dev
);
277 return ERR_PTR(-ENODEV
);
284 * drm_minor_release - Release DRM minor
285 * @minor: Pointer to DRM minor object
287 * Release a minor that was previously acquired via drm_minor_acquire().
289 void drm_minor_release(struct drm_minor
*minor
)
291 drm_dev_unref(minor
->dev
);
295 * DOC: driver instance overview
297 * A device instance for a drm driver is represented by struct &drm_device. This
298 * is allocated with drm_dev_alloc(), usually from bus-specific ->probe()
299 * callbacks implemented by the driver. The driver then needs to initialize all
300 * the various subsystems for the drm device like memory management, vblank
301 * handling, modesetting support and intial output configuration plus obviously
302 * initialize all the corresponding hardware bits. Finally when everything is up
303 * and running and ready for userspace the device instance can be published
304 * using drm_dev_register().
306 * There is also deprecated support for initalizing device instances using
307 * bus-specific helpers and the ->load() callback. But due to
308 * backwards-compatibility needs the device instance have to be published too
309 * early, which requires unpretty global locking to make safe and is therefore
310 * only support for existing drivers not yet converted to the new scheme.
312 * When cleaning up a device instance everything needs to be done in reverse:
313 * First unpublish the device instance with drm_dev_unregister(). Then clean up
314 * any other resources allocated at device initialization and drop the driver's
315 * reference to &drm_device using drm_dev_unref().
317 * Note that the lifetime rules for &drm_device instance has still a lot of
318 * historical baggage. Hence use the reference counting provided by
319 * drm_dev_ref() and drm_dev_unref() only carefully.
321 * Also note that embedding of &drm_device is currently not (yet) supported (but
322 * it would be easy to add). Drivers can store driver-private data in the
323 * dev_priv field of &drm_device.
326 static int drm_dev_set_unique(struct drm_device
*dev
, const char *name
)
329 dev
->unique
= kstrdup(name
, GFP_KERNEL
);
331 return dev
->unique
? 0 : -ENOMEM
;
335 * drm_put_dev - Unregister and release a DRM device
338 * Called at module unload time or when a PCI device is unplugged.
340 * Cleans up all DRM device, calling drm_lastclose().
342 * Note: Use of this function is deprecated. It will eventually go away
343 * completely. Please use drm_dev_unregister() and drm_dev_unref() explicitly
344 * instead to make sure that the device isn't userspace accessible any more
345 * while teardown is in progress, ensuring that userspace can't access an
346 * inconsistent state.
348 void drm_put_dev(struct drm_device
*dev
)
353 DRM_ERROR("cleanup called no dev\n");
357 drm_dev_unregister(dev
);
360 EXPORT_SYMBOL(drm_put_dev
);
362 void drm_unplug_dev(struct drm_device
*dev
)
364 /* for a USB device */
365 drm_dev_unregister(dev
);
367 mutex_lock(&drm_global_mutex
);
369 drm_device_set_unplugged(dev
);
371 if (dev
->open_count
== 0) {
374 mutex_unlock(&drm_global_mutex
);
376 EXPORT_SYMBOL(drm_unplug_dev
);
380 * We want to be able to allocate our own "struct address_space" to control
381 * memory-mappings in VRAM (or stolen RAM, ...). However, core MM does not allow
382 * stand-alone address_space objects, so we need an underlying inode. As there
383 * is no way to allocate an independent inode easily, we need a fake internal
386 * The drm_fs_inode_new() function allocates a new inode, drm_fs_inode_free()
387 * frees it again. You are allowed to use iget() and iput() to get references to
388 * the inode. But each drm_fs_inode_new() call must be paired with exactly one
389 * drm_fs_inode_free() call (which does not have to be the last iput()).
390 * We use drm_fs_inode_*() to manage our internal VFS mount-point and share it
391 * between multiple inode-users. You could, technically, call
392 * iget() + drm_fs_inode_free() directly after alloc and sometime later do an
393 * iput(), but this way you'd end up with a new vfsmount for each inode.
396 static int drm_fs_cnt
;
397 static struct vfsmount
*drm_fs_mnt
;
399 static const struct dentry_operations drm_fs_dops
= {
400 .d_dname
= simple_dname
,
403 static const struct super_operations drm_fs_sops
= {
404 .statfs
= simple_statfs
,
407 static struct dentry
*drm_fs_mount(struct file_system_type
*fs_type
, int flags
,
408 const char *dev_name
, void *data
)
410 return mount_pseudo(fs_type
,
417 static struct file_system_type drm_fs_type
= {
419 .owner
= THIS_MODULE
,
420 .mount
= drm_fs_mount
,
421 .kill_sb
= kill_anon_super
,
424 static struct inode
*drm_fs_inode_new(void)
429 r
= simple_pin_fs(&drm_fs_type
, &drm_fs_mnt
, &drm_fs_cnt
);
431 DRM_ERROR("Cannot mount pseudo fs: %d\n", r
);
435 inode
= alloc_anon_inode(drm_fs_mnt
->mnt_sb
);
437 simple_release_fs(&drm_fs_mnt
, &drm_fs_cnt
);
442 static void drm_fs_inode_free(struct inode
*inode
)
446 simple_release_fs(&drm_fs_mnt
, &drm_fs_cnt
);
451 * drm_dev_init - Initialise new DRM device
453 * @driver: DRM driver
454 * @parent: Parent device object
456 * Initialize a new DRM device. No device registration is done.
457 * Call drm_dev_register() to advertice the device to user space and register it
458 * with other core subsystems. This should be done last in the device
459 * initialization sequence to make sure userspace can't access an inconsistent
462 * The initial ref-count of the object is 1. Use drm_dev_ref() and
463 * drm_dev_unref() to take and drop further ref-counts.
465 * Note that for purely virtual devices @parent can be NULL.
467 * Drivers that do not want to allocate their own device struct
468 * embedding struct &drm_device can call drm_dev_alloc() instead.
471 * 0 on success, or error code on failure.
473 int drm_dev_init(struct drm_device
*dev
,
474 struct drm_driver
*driver
,
475 struct device
*parent
)
479 kref_init(&dev
->ref
);
481 dev
->driver
= driver
;
483 INIT_LIST_HEAD(&dev
->filelist
);
484 INIT_LIST_HEAD(&dev
->ctxlist
);
485 INIT_LIST_HEAD(&dev
->vmalist
);
486 INIT_LIST_HEAD(&dev
->maplist
);
487 INIT_LIST_HEAD(&dev
->vblank_event_list
);
489 spin_lock_init(&dev
->buf_lock
);
490 spin_lock_init(&dev
->event_lock
);
491 mutex_init(&dev
->struct_mutex
);
492 mutex_init(&dev
->filelist_mutex
);
493 mutex_init(&dev
->ctxlist_mutex
);
494 mutex_init(&dev
->master_mutex
);
496 dev
->anon_inode
= drm_fs_inode_new();
497 if (IS_ERR(dev
->anon_inode
)) {
498 ret
= PTR_ERR(dev
->anon_inode
);
499 DRM_ERROR("Cannot allocate anonymous inode: %d\n", ret
);
503 if (drm_core_check_feature(dev
, DRIVER_MODESET
)) {
504 ret
= drm_minor_alloc(dev
, DRM_MINOR_CONTROL
);
509 if (drm_core_check_feature(dev
, DRIVER_RENDER
)) {
510 ret
= drm_minor_alloc(dev
, DRM_MINOR_RENDER
);
515 ret
= drm_minor_alloc(dev
, DRM_MINOR_LEGACY
);
519 ret
= drm_ht_create(&dev
->map_hash
, 12);
523 drm_legacy_ctxbitmap_init(dev
);
525 if (drm_core_check_feature(dev
, DRIVER_GEM
)) {
526 ret
= drm_gem_init(dev
);
528 DRM_ERROR("Cannot initialize graphics execution manager (GEM)\n");
533 /* Use the parent device name as DRM device unique identifier, but fall
534 * back to the driver name for virtual devices like vgem. */
535 ret
= drm_dev_set_unique(dev
, parent
? dev_name(parent
) : driver
->name
);
542 if (drm_core_check_feature(dev
, DRIVER_GEM
))
543 drm_gem_destroy(dev
);
545 drm_legacy_ctxbitmap_cleanup(dev
);
546 drm_ht_remove(&dev
->map_hash
);
548 drm_minor_free(dev
, DRM_MINOR_LEGACY
);
549 drm_minor_free(dev
, DRM_MINOR_RENDER
);
550 drm_minor_free(dev
, DRM_MINOR_CONTROL
);
551 drm_fs_inode_free(dev
->anon_inode
);
553 mutex_destroy(&dev
->master_mutex
);
556 EXPORT_SYMBOL(drm_dev_init
);
559 * drm_dev_alloc - Allocate new DRM device
560 * @driver: DRM driver to allocate device for
561 * @parent: Parent device object
563 * Allocate and initialize a new DRM device. No device registration is done.
564 * Call drm_dev_register() to advertice the device to user space and register it
565 * with other core subsystems. This should be done last in the device
566 * initialization sequence to make sure userspace can't access an inconsistent
569 * The initial ref-count of the object is 1. Use drm_dev_ref() and
570 * drm_dev_unref() to take and drop further ref-counts.
572 * Note that for purely virtual devices @parent can be NULL.
574 * Drivers that wish to subclass or embed struct &drm_device into their
575 * own struct should look at using drm_dev_init() instead.
578 * Pointer to new DRM device, or NULL if out of memory.
580 struct drm_device
*drm_dev_alloc(struct drm_driver
*driver
,
581 struct device
*parent
)
583 struct drm_device
*dev
;
586 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
590 ret
= drm_dev_init(dev
, driver
, parent
);
598 EXPORT_SYMBOL(drm_dev_alloc
);
600 static void drm_dev_release(struct kref
*ref
)
602 struct drm_device
*dev
= container_of(ref
, struct drm_device
, ref
);
604 if (drm_core_check_feature(dev
, DRIVER_GEM
))
605 drm_gem_destroy(dev
);
607 drm_legacy_ctxbitmap_cleanup(dev
);
608 drm_ht_remove(&dev
->map_hash
);
609 drm_fs_inode_free(dev
->anon_inode
);
611 drm_minor_free(dev
, DRM_MINOR_LEGACY
);
612 drm_minor_free(dev
, DRM_MINOR_RENDER
);
613 drm_minor_free(dev
, DRM_MINOR_CONTROL
);
615 mutex_destroy(&dev
->master_mutex
);
621 * drm_dev_ref - Take reference of a DRM device
622 * @dev: device to take reference of or NULL
624 * This increases the ref-count of @dev by one. You *must* already own a
625 * reference when calling this. Use drm_dev_unref() to drop this reference
628 * This function never fails. However, this function does not provide *any*
629 * guarantee whether the device is alive or running. It only provides a
630 * reference to the object and the memory associated with it.
632 void drm_dev_ref(struct drm_device
*dev
)
637 EXPORT_SYMBOL(drm_dev_ref
);
640 * drm_dev_unref - Drop reference of a DRM device
641 * @dev: device to drop reference of or NULL
643 * This decreases the ref-count of @dev by one. The device is destroyed if the
644 * ref-count drops to zero.
646 void drm_dev_unref(struct drm_device
*dev
)
649 kref_put(&dev
->ref
, drm_dev_release
);
651 EXPORT_SYMBOL(drm_dev_unref
);
654 * drm_dev_register - Register DRM device
655 * @dev: Device to register
656 * @flags: Flags passed to the driver's .load() function
658 * Register the DRM device @dev with the system, advertise device to user-space
659 * and start normal device operation. @dev must be allocated via drm_dev_alloc()
662 * Never call this twice on any device!
664 * NOTE: To ensure backward compatibility with existing drivers method this
665 * function calls the ->load() method after registering the device nodes,
666 * creating race conditions. Usage of the ->load() methods is therefore
667 * deprecated, drivers must perform all initialization before calling
668 * drm_dev_register().
671 * 0 on success, negative error code on failure.
673 int drm_dev_register(struct drm_device
*dev
, unsigned long flags
)
677 mutex_lock(&drm_global_mutex
);
679 ret
= drm_minor_register(dev
, DRM_MINOR_CONTROL
);
683 ret
= drm_minor_register(dev
, DRM_MINOR_RENDER
);
687 ret
= drm_minor_register(dev
, DRM_MINOR_LEGACY
);
691 if (dev
->driver
->load
) {
692 ret
= dev
->driver
->load(dev
, flags
);
697 if (drm_core_check_feature(dev
, DRIVER_MODESET
))
698 drm_modeset_register_all(dev
);
704 drm_minor_unregister(dev
, DRM_MINOR_LEGACY
);
705 drm_minor_unregister(dev
, DRM_MINOR_RENDER
);
706 drm_minor_unregister(dev
, DRM_MINOR_CONTROL
);
708 mutex_unlock(&drm_global_mutex
);
711 EXPORT_SYMBOL(drm_dev_register
);
714 * drm_dev_unregister - Unregister DRM device
715 * @dev: Device to unregister
717 * Unregister the DRM device from the system. This does the reverse of
718 * drm_dev_register() but does not deallocate the device. The caller must call
719 * drm_dev_unref() to drop their final reference.
721 * This should be called first in the device teardown code to make sure
722 * userspace can't access the device instance any more.
724 void drm_dev_unregister(struct drm_device
*dev
)
726 struct drm_map_list
*r_list
, *list_temp
;
730 if (drm_core_check_feature(dev
, DRIVER_MODESET
))
731 drm_modeset_unregister_all(dev
);
733 if (dev
->driver
->unload
)
734 dev
->driver
->unload(dev
);
737 drm_pci_agp_destroy(dev
);
739 drm_vblank_cleanup(dev
);
741 list_for_each_entry_safe(r_list
, list_temp
, &dev
->maplist
, head
)
742 drm_legacy_rmmap(dev
, r_list
->map
);
744 drm_minor_unregister(dev
, DRM_MINOR_LEGACY
);
745 drm_minor_unregister(dev
, DRM_MINOR_RENDER
);
746 drm_minor_unregister(dev
, DRM_MINOR_CONTROL
);
748 EXPORT_SYMBOL(drm_dev_unregister
);
752 * The DRM core module initializes all global DRM objects and makes them
753 * available to drivers. Once setup, drivers can probe their respective
755 * Currently, core management includes:
756 * - The "DRM-Global" key/value database
757 * - Global ID management for connectors
758 * - DRM major number allocation
759 * - DRM minor management
763 * Furthermore, the DRM core provides dynamic char-dev lookups. For each
764 * interface registered on a DRM device, you can request minor numbers from DRM
765 * core. DRM core takes care of major-number management and char-dev
766 * registration. A stub ->open() callback forwards any open() requests to the
770 static int drm_stub_open(struct inode
*inode
, struct file
*filp
)
772 const struct file_operations
*new_fops
;
773 struct drm_minor
*minor
;
778 mutex_lock(&drm_global_mutex
);
779 minor
= drm_minor_acquire(iminor(inode
));
781 err
= PTR_ERR(minor
);
785 new_fops
= fops_get(minor
->dev
->driver
->fops
);
791 replace_fops(filp
, new_fops
);
792 if (filp
->f_op
->open
)
793 err
= filp
->f_op
->open(inode
, filp
);
798 drm_minor_release(minor
);
800 mutex_unlock(&drm_global_mutex
);
804 static const struct file_operations drm_stub_fops
= {
805 .owner
= THIS_MODULE
,
806 .open
= drm_stub_open
,
807 .llseek
= noop_llseek
,
810 static int __init
drm_core_init(void)
815 drm_connector_ida_init();
816 idr_init(&drm_minors_idr
);
818 if (register_chrdev(DRM_MAJOR
, "drm", &drm_stub_fops
))
821 ret
= drm_sysfs_init();
823 printk(KERN_ERR
"DRM: Error creating drm class.\n");
827 drm_debugfs_root
= debugfs_create_dir("dri", NULL
);
828 if (!drm_debugfs_root
) {
829 DRM_ERROR("Cannot create /sys/kernel/debug/dri\n");
834 DRM_INFO("Initialized %s %d.%d.%d %s\n",
835 CORE_NAME
, CORE_MAJOR
, CORE_MINOR
, CORE_PATCHLEVEL
, CORE_DATE
);
840 unregister_chrdev(DRM_MAJOR
, "drm");
842 idr_destroy(&drm_minors_idr
);
847 static void __exit
drm_core_exit(void)
849 debugfs_remove(drm_debugfs_root
);
852 unregister_chrdev(DRM_MAJOR
, "drm");
854 drm_connector_ida_destroy();
855 idr_destroy(&drm_minors_idr
);
858 module_init(drm_core_init
);
859 module_exit(drm_core_exit
);