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_legacy.h"
38 #include "drm_internal.h"
41 * drm_debug: Enable debug output.
42 * Bitmask of DRM_UT_x. See include/drm/drmP.h for details.
44 unsigned int drm_debug
= 0;
45 EXPORT_SYMBOL(drm_debug
);
47 MODULE_AUTHOR(CORE_AUTHOR
);
48 MODULE_DESCRIPTION(CORE_DESC
);
49 MODULE_LICENSE("GPL and additional rights");
50 MODULE_PARM_DESC(debug
, "Enable debug output, where each bit enables a debug category.\n"
51 "\t\tBit 0 (0x01) will enable CORE messages (drm core code)\n"
52 "\t\tBit 1 (0x02) will enable DRIVER messages (drm controller code)\n"
53 "\t\tBit 2 (0x04) will enable KMS messages (modesetting code)\n"
54 "\t\tBit 3 (0x08) will enable PRIME messages (prime code)\n"
55 "\t\tBit 4 (0x10) will enable ATOMIC messages (atomic code)\n"
56 "\t\tBit 5 (0x20) will enable VBL messages (vblank code)");
57 module_param_named(debug
, drm_debug
, int, 0600);
59 static DEFINE_SPINLOCK(drm_minor_lock
);
60 static struct idr drm_minors_idr
;
62 static struct dentry
*drm_debugfs_root
;
64 void drm_err(const char *format
, ...)
69 va_start(args
, format
);
74 printk(KERN_ERR
"[" DRM_NAME
":%ps] *ERROR* %pV",
75 __builtin_return_address(0), &vaf
);
79 EXPORT_SYMBOL(drm_err
);
81 void drm_ut_debug_printk(const char *function_name
, const char *format
, ...)
86 va_start(args
, format
);
90 printk(KERN_DEBUG
"[" DRM_NAME
":%s] %pV", function_name
, &vaf
);
94 EXPORT_SYMBOL(drm_ut_debug_printk
);
96 struct drm_master
*drm_master_create(struct drm_minor
*minor
)
98 struct drm_master
*master
;
100 master
= kzalloc(sizeof(*master
), GFP_KERNEL
);
104 kref_init(&master
->refcount
);
105 spin_lock_init(&master
->lock
.spinlock
);
106 init_waitqueue_head(&master
->lock
.lock_queue
);
107 idr_init(&master
->magic_map
);
108 master
->minor
= minor
;
113 struct drm_master
*drm_master_get(struct drm_master
*master
)
115 kref_get(&master
->refcount
);
118 EXPORT_SYMBOL(drm_master_get
);
120 static void drm_master_destroy(struct kref
*kref
)
122 struct drm_master
*master
= container_of(kref
, struct drm_master
, refcount
);
123 struct drm_device
*dev
= master
->minor
->dev
;
125 if (dev
->driver
->master_destroy
)
126 dev
->driver
->master_destroy(dev
, master
);
128 drm_legacy_master_rmmaps(dev
, master
);
130 idr_destroy(&master
->magic_map
);
131 kfree(master
->unique
);
135 void drm_master_put(struct drm_master
**master
)
137 kref_put(&(*master
)->refcount
, drm_master_destroy
);
140 EXPORT_SYMBOL(drm_master_put
);
142 int drm_setmaster_ioctl(struct drm_device
*dev
, void *data
,
143 struct drm_file
*file_priv
)
147 mutex_lock(&dev
->master_mutex
);
148 if (file_priv
->is_master
)
151 if (file_priv
->minor
->master
) {
156 if (!file_priv
->master
) {
161 if (!file_priv
->allowed_master
) {
162 ret
= drm_new_set_master(dev
, file_priv
);
166 file_priv
->minor
->master
= drm_master_get(file_priv
->master
);
167 file_priv
->is_master
= 1;
168 if (dev
->driver
->master_set
) {
169 ret
= dev
->driver
->master_set(dev
, file_priv
, false);
170 if (unlikely(ret
!= 0)) {
171 file_priv
->is_master
= 0;
172 drm_master_put(&file_priv
->minor
->master
);
177 mutex_unlock(&dev
->master_mutex
);
181 int drm_dropmaster_ioctl(struct drm_device
*dev
, void *data
,
182 struct drm_file
*file_priv
)
186 mutex_lock(&dev
->master_mutex
);
187 if (!file_priv
->is_master
)
190 if (!file_priv
->minor
->master
)
194 if (dev
->driver
->master_drop
)
195 dev
->driver
->master_drop(dev
, file_priv
, false);
196 drm_master_put(&file_priv
->minor
->master
);
197 file_priv
->is_master
= 0;
200 mutex_unlock(&dev
->master_mutex
);
206 * A DRM device can provide several char-dev interfaces on the DRM-Major. Each
207 * of them is represented by a drm_minor object. Depending on the capabilities
208 * of the device-driver, different interfaces are registered.
210 * Minors can be accessed via dev->$minor_name. This pointer is either
211 * NULL or a valid drm_minor pointer and stays valid as long as the device is
212 * valid. This means, DRM minors have the same life-time as the underlying
213 * device. However, this doesn't mean that the minor is active. Minors are
214 * registered and unregistered dynamically according to device-state.
217 static struct drm_minor
**drm_minor_get_slot(struct drm_device
*dev
,
221 case DRM_MINOR_LEGACY
:
222 return &dev
->primary
;
223 case DRM_MINOR_RENDER
:
225 case DRM_MINOR_CONTROL
:
226 return &dev
->control
;
232 static int drm_minor_alloc(struct drm_device
*dev
, unsigned int type
)
234 struct drm_minor
*minor
;
238 minor
= kzalloc(sizeof(*minor
), GFP_KERNEL
);
245 idr_preload(GFP_KERNEL
);
246 spin_lock_irqsave(&drm_minor_lock
, flags
);
247 r
= idr_alloc(&drm_minors_idr
,
252 spin_unlock_irqrestore(&drm_minor_lock
, flags
);
260 minor
->kdev
= drm_sysfs_minor_alloc(minor
);
261 if (IS_ERR(minor
->kdev
)) {
262 r
= PTR_ERR(minor
->kdev
);
266 *drm_minor_get_slot(dev
, type
) = minor
;
270 spin_lock_irqsave(&drm_minor_lock
, flags
);
271 idr_remove(&drm_minors_idr
, minor
->index
);
272 spin_unlock_irqrestore(&drm_minor_lock
, flags
);
278 static void drm_minor_free(struct drm_device
*dev
, unsigned int type
)
280 struct drm_minor
**slot
, *minor
;
283 slot
= drm_minor_get_slot(dev
, type
);
288 put_device(minor
->kdev
);
290 spin_lock_irqsave(&drm_minor_lock
, flags
);
291 idr_remove(&drm_minors_idr
, minor
->index
);
292 spin_unlock_irqrestore(&drm_minor_lock
, flags
);
298 static int drm_minor_register(struct drm_device
*dev
, unsigned int type
)
300 struct drm_minor
*minor
;
306 minor
= *drm_minor_get_slot(dev
, type
);
310 ret
= drm_debugfs_init(minor
, minor
->index
, drm_debugfs_root
);
312 DRM_ERROR("DRM: Failed to initialize /sys/kernel/debug/dri.\n");
316 ret
= device_add(minor
->kdev
);
320 /* replace NULL with @minor so lookups will succeed from now on */
321 spin_lock_irqsave(&drm_minor_lock
, flags
);
322 idr_replace(&drm_minors_idr
, minor
, minor
->index
);
323 spin_unlock_irqrestore(&drm_minor_lock
, flags
);
325 DRM_DEBUG("new minor registered %d\n", minor
->index
);
329 drm_debugfs_cleanup(minor
);
333 static void drm_minor_unregister(struct drm_device
*dev
, unsigned int type
)
335 struct drm_minor
*minor
;
338 minor
= *drm_minor_get_slot(dev
, type
);
339 if (!minor
|| !device_is_registered(minor
->kdev
))
342 /* replace @minor with NULL so lookups will fail from now on */
343 spin_lock_irqsave(&drm_minor_lock
, flags
);
344 idr_replace(&drm_minors_idr
, NULL
, minor
->index
);
345 spin_unlock_irqrestore(&drm_minor_lock
, flags
);
347 device_del(minor
->kdev
);
348 dev_set_drvdata(minor
->kdev
, NULL
); /* safety belt */
349 drm_debugfs_cleanup(minor
);
353 * drm_minor_acquire - Acquire a DRM minor
354 * @minor_id: Minor ID of the DRM-minor
356 * Looks up the given minor-ID and returns the respective DRM-minor object. The
357 * refence-count of the underlying device is increased so you must release this
358 * object with drm_minor_release().
360 * As long as you hold this minor, it is guaranteed that the object and the
361 * minor->dev pointer will stay valid! However, the device may get unplugged and
362 * unregistered while you hold the minor.
365 * Pointer to minor-object with increased device-refcount, or PTR_ERR on
368 struct drm_minor
*drm_minor_acquire(unsigned int minor_id
)
370 struct drm_minor
*minor
;
373 spin_lock_irqsave(&drm_minor_lock
, flags
);
374 minor
= idr_find(&drm_minors_idr
, minor_id
);
376 drm_dev_ref(minor
->dev
);
377 spin_unlock_irqrestore(&drm_minor_lock
, flags
);
380 return ERR_PTR(-ENODEV
);
381 } else if (drm_device_is_unplugged(minor
->dev
)) {
382 drm_dev_unref(minor
->dev
);
383 return ERR_PTR(-ENODEV
);
390 * drm_minor_release - Release DRM minor
391 * @minor: Pointer to DRM minor object
393 * Release a minor that was previously acquired via drm_minor_acquire().
395 void drm_minor_release(struct drm_minor
*minor
)
397 drm_dev_unref(minor
->dev
);
401 * DOC: driver instance overview
403 * A device instance for a drm driver is represented by struct &drm_device. This
404 * is allocated with drm_dev_alloc(), usually from bus-specific ->probe()
405 * callbacks implemented by the driver. The driver then needs to initialize all
406 * the various subsystems for the drm device like memory management, vblank
407 * handling, modesetting support and intial output configuration plus obviously
408 * initialize all the corresponding hardware bits. An important part of this is
409 * also calling drm_dev_set_unique() to set the userspace-visible unique name of
410 * this device instance. Finally when everything is up and running and ready for
411 * userspace the device instance can be published using drm_dev_register().
413 * There is also deprecated support for initalizing device instances using
414 * bus-specific helpers and the ->load() callback. But due to
415 * backwards-compatibility needs the device instance have to be published too
416 * early, which requires unpretty global locking to make safe and is therefore
417 * only support for existing drivers not yet converted to the new scheme.
419 * When cleaning up a device instance everything needs to be done in reverse:
420 * First unpublish the device instance with drm_dev_unregister(). Then clean up
421 * any other resources allocated at device initialization and drop the driver's
422 * reference to &drm_device using drm_dev_unref().
424 * Note that the lifetime rules for &drm_device instance has still a lot of
425 * historical baggage. Hence use the reference counting provided by
426 * drm_dev_ref() and drm_dev_unref() only carefully.
428 * Also note that embedding of &drm_device is currently not (yet) supported (but
429 * it would be easy to add). Drivers can store driver-private data in the
430 * dev_priv field of &drm_device.
434 * drm_put_dev - Unregister and release a DRM device
437 * Called at module unload time or when a PCI device is unplugged.
439 * Cleans up all DRM device, calling drm_lastclose().
441 * Note: Use of this function is deprecated. It will eventually go away
442 * completely. Please use drm_dev_unregister() and drm_dev_unref() explicitly
443 * instead to make sure that the device isn't userspace accessible any more
444 * while teardown is in progress, ensuring that userspace can't access an
445 * inconsistent state.
447 void drm_put_dev(struct drm_device
*dev
)
452 DRM_ERROR("cleanup called no dev\n");
456 drm_dev_unregister(dev
);
459 EXPORT_SYMBOL(drm_put_dev
);
461 void drm_unplug_dev(struct drm_device
*dev
)
463 /* for a USB device */
464 drm_minor_unregister(dev
, DRM_MINOR_LEGACY
);
465 drm_minor_unregister(dev
, DRM_MINOR_RENDER
);
466 drm_minor_unregister(dev
, DRM_MINOR_CONTROL
);
468 mutex_lock(&drm_global_mutex
);
470 drm_device_set_unplugged(dev
);
472 if (dev
->open_count
== 0) {
475 mutex_unlock(&drm_global_mutex
);
477 EXPORT_SYMBOL(drm_unplug_dev
);
481 * We want to be able to allocate our own "struct address_space" to control
482 * memory-mappings in VRAM (or stolen RAM, ...). However, core MM does not allow
483 * stand-alone address_space objects, so we need an underlying inode. As there
484 * is no way to allocate an independent inode easily, we need a fake internal
487 * The drm_fs_inode_new() function allocates a new inode, drm_fs_inode_free()
488 * frees it again. You are allowed to use iget() and iput() to get references to
489 * the inode. But each drm_fs_inode_new() call must be paired with exactly one
490 * drm_fs_inode_free() call (which does not have to be the last iput()).
491 * We use drm_fs_inode_*() to manage our internal VFS mount-point and share it
492 * between multiple inode-users. You could, technically, call
493 * iget() + drm_fs_inode_free() directly after alloc and sometime later do an
494 * iput(), but this way you'd end up with a new vfsmount for each inode.
497 static int drm_fs_cnt
;
498 static struct vfsmount
*drm_fs_mnt
;
500 static const struct dentry_operations drm_fs_dops
= {
501 .d_dname
= simple_dname
,
504 static const struct super_operations drm_fs_sops
= {
505 .statfs
= simple_statfs
,
508 static struct dentry
*drm_fs_mount(struct file_system_type
*fs_type
, int flags
,
509 const char *dev_name
, void *data
)
511 return mount_pseudo(fs_type
,
518 static struct file_system_type drm_fs_type
= {
520 .owner
= THIS_MODULE
,
521 .mount
= drm_fs_mount
,
522 .kill_sb
= kill_anon_super
,
525 static struct inode
*drm_fs_inode_new(void)
530 r
= simple_pin_fs(&drm_fs_type
, &drm_fs_mnt
, &drm_fs_cnt
);
532 DRM_ERROR("Cannot mount pseudo fs: %d\n", r
);
536 inode
= alloc_anon_inode(drm_fs_mnt
->mnt_sb
);
538 simple_release_fs(&drm_fs_mnt
, &drm_fs_cnt
);
543 static void drm_fs_inode_free(struct inode
*inode
)
547 simple_release_fs(&drm_fs_mnt
, &drm_fs_cnt
);
552 * drm_dev_alloc - Allocate new DRM device
553 * @driver: DRM driver to allocate device for
554 * @parent: Parent device object
556 * Allocate and initialize a new DRM device. No device registration is done.
557 * Call drm_dev_register() to advertice the device to user space and register it
558 * with other core subsystems. This should be done last in the device
559 * initialization sequence to make sure userspace can't access an inconsistent
562 * The initial ref-count of the object is 1. Use drm_dev_ref() and
563 * drm_dev_unref() to take and drop further ref-counts.
565 * Note that for purely virtual devices @parent can be NULL.
568 * Pointer to new DRM device, or NULL if out of memory.
570 struct drm_device
*drm_dev_alloc(struct drm_driver
*driver
,
571 struct device
*parent
)
573 struct drm_device
*dev
;
576 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
580 kref_init(&dev
->ref
);
582 dev
->driver
= driver
;
584 INIT_LIST_HEAD(&dev
->filelist
);
585 INIT_LIST_HEAD(&dev
->ctxlist
);
586 INIT_LIST_HEAD(&dev
->vmalist
);
587 INIT_LIST_HEAD(&dev
->maplist
);
588 INIT_LIST_HEAD(&dev
->vblank_event_list
);
590 spin_lock_init(&dev
->buf_lock
);
591 spin_lock_init(&dev
->event_lock
);
592 mutex_init(&dev
->struct_mutex
);
593 mutex_init(&dev
->filelist_mutex
);
594 mutex_init(&dev
->ctxlist_mutex
);
595 mutex_init(&dev
->master_mutex
);
597 dev
->anon_inode
= drm_fs_inode_new();
598 if (IS_ERR(dev
->anon_inode
)) {
599 ret
= PTR_ERR(dev
->anon_inode
);
600 DRM_ERROR("Cannot allocate anonymous inode: %d\n", ret
);
604 if (drm_core_check_feature(dev
, DRIVER_MODESET
)) {
605 ret
= drm_minor_alloc(dev
, DRM_MINOR_CONTROL
);
609 WARN_ON(driver
->suspend
|| driver
->resume
);
612 if (drm_core_check_feature(dev
, DRIVER_RENDER
)) {
613 ret
= drm_minor_alloc(dev
, DRM_MINOR_RENDER
);
618 ret
= drm_minor_alloc(dev
, DRM_MINOR_LEGACY
);
622 if (drm_ht_create(&dev
->map_hash
, 12))
625 drm_legacy_ctxbitmap_init(dev
);
627 if (drm_core_check_feature(dev
, DRIVER_GEM
)) {
628 ret
= drm_gem_init(dev
);
630 DRM_ERROR("Cannot initialize graphics execution manager (GEM)\n");
636 ret
= drm_dev_set_unique(dev
, dev_name(parent
));
644 if (drm_core_check_feature(dev
, DRIVER_GEM
))
645 drm_gem_destroy(dev
);
647 drm_legacy_ctxbitmap_cleanup(dev
);
648 drm_ht_remove(&dev
->map_hash
);
650 drm_minor_free(dev
, DRM_MINOR_LEGACY
);
651 drm_minor_free(dev
, DRM_MINOR_RENDER
);
652 drm_minor_free(dev
, DRM_MINOR_CONTROL
);
653 drm_fs_inode_free(dev
->anon_inode
);
655 mutex_destroy(&dev
->master_mutex
);
659 EXPORT_SYMBOL(drm_dev_alloc
);
661 static void drm_dev_release(struct kref
*ref
)
663 struct drm_device
*dev
= container_of(ref
, struct drm_device
, ref
);
665 if (drm_core_check_feature(dev
, DRIVER_GEM
))
666 drm_gem_destroy(dev
);
668 drm_legacy_ctxbitmap_cleanup(dev
);
669 drm_ht_remove(&dev
->map_hash
);
670 drm_fs_inode_free(dev
->anon_inode
);
672 drm_minor_free(dev
, DRM_MINOR_LEGACY
);
673 drm_minor_free(dev
, DRM_MINOR_RENDER
);
674 drm_minor_free(dev
, DRM_MINOR_CONTROL
);
676 mutex_destroy(&dev
->master_mutex
);
682 * drm_dev_ref - Take reference of a DRM device
683 * @dev: device to take reference of or NULL
685 * This increases the ref-count of @dev by one. You *must* already own a
686 * reference when calling this. Use drm_dev_unref() to drop this reference
689 * This function never fails. However, this function does not provide *any*
690 * guarantee whether the device is alive or running. It only provides a
691 * reference to the object and the memory associated with it.
693 void drm_dev_ref(struct drm_device
*dev
)
698 EXPORT_SYMBOL(drm_dev_ref
);
701 * drm_dev_unref - Drop reference of a DRM device
702 * @dev: device to drop reference of or NULL
704 * This decreases the ref-count of @dev by one. The device is destroyed if the
705 * ref-count drops to zero.
707 void drm_dev_unref(struct drm_device
*dev
)
710 kref_put(&dev
->ref
, drm_dev_release
);
712 EXPORT_SYMBOL(drm_dev_unref
);
715 * drm_dev_register - Register DRM device
716 * @dev: Device to register
717 * @flags: Flags passed to the driver's .load() function
719 * Register the DRM device @dev with the system, advertise device to user-space
720 * and start normal device operation. @dev must be allocated via drm_dev_alloc()
721 * previously. Right after drm_dev_register() the driver should call
722 * drm_connector_register_all() to register all connectors in sysfs. This is
723 * a separate call for backward compatibility with drivers still using
724 * the deprecated ->load() callback, where connectors are registered from within
725 * the ->load() callback.
727 * Never call this twice on any device!
729 * NOTE: To ensure backward compatibility with existing drivers method this
730 * function calls the ->load() method after registering the device nodes,
731 * creating race conditions. Usage of the ->load() methods is therefore
732 * deprecated, drivers must perform all initialization before calling
733 * drm_dev_register().
736 * 0 on success, negative error code on failure.
738 int drm_dev_register(struct drm_device
*dev
, unsigned long flags
)
742 mutex_lock(&drm_global_mutex
);
744 ret
= drm_minor_register(dev
, DRM_MINOR_CONTROL
);
748 ret
= drm_minor_register(dev
, DRM_MINOR_RENDER
);
752 ret
= drm_minor_register(dev
, DRM_MINOR_LEGACY
);
756 if (dev
->driver
->load
) {
757 ret
= dev
->driver
->load(dev
, flags
);
766 drm_minor_unregister(dev
, DRM_MINOR_LEGACY
);
767 drm_minor_unregister(dev
, DRM_MINOR_RENDER
);
768 drm_minor_unregister(dev
, DRM_MINOR_CONTROL
);
770 mutex_unlock(&drm_global_mutex
);
773 EXPORT_SYMBOL(drm_dev_register
);
776 * drm_dev_unregister - Unregister DRM device
777 * @dev: Device to unregister
779 * Unregister the DRM device from the system. This does the reverse of
780 * drm_dev_register() but does not deallocate the device. The caller must call
781 * drm_dev_unref() to drop their final reference.
783 * This should be called first in the device teardown code to make sure
784 * userspace can't access the device instance any more.
786 void drm_dev_unregister(struct drm_device
*dev
)
788 struct drm_map_list
*r_list
, *list_temp
;
792 if (dev
->driver
->unload
)
793 dev
->driver
->unload(dev
);
796 drm_pci_agp_destroy(dev
);
798 drm_vblank_cleanup(dev
);
800 list_for_each_entry_safe(r_list
, list_temp
, &dev
->maplist
, head
)
801 drm_legacy_rmmap(dev
, r_list
->map
);
803 drm_minor_unregister(dev
, DRM_MINOR_LEGACY
);
804 drm_minor_unregister(dev
, DRM_MINOR_RENDER
);
805 drm_minor_unregister(dev
, DRM_MINOR_CONTROL
);
807 EXPORT_SYMBOL(drm_dev_unregister
);
810 * drm_dev_set_unique - Set the unique name of a DRM device
811 * @dev: device of which to set the unique name
814 * Sets the unique name of a DRM device using the specified string. Drivers
815 * can use this at driver probe time if the unique name of the devices they
818 * Return: 0 on success or a negative error code on failure.
820 int drm_dev_set_unique(struct drm_device
*dev
, const char *name
)
823 dev
->unique
= kstrdup(name
, GFP_KERNEL
);
825 return dev
->unique
? 0 : -ENOMEM
;
827 EXPORT_SYMBOL(drm_dev_set_unique
);
831 * The DRM core module initializes all global DRM objects and makes them
832 * available to drivers. Once setup, drivers can probe their respective
834 * Currently, core management includes:
835 * - The "DRM-Global" key/value database
836 * - Global ID management for connectors
837 * - DRM major number allocation
838 * - DRM minor management
842 * Furthermore, the DRM core provides dynamic char-dev lookups. For each
843 * interface registered on a DRM device, you can request minor numbers from DRM
844 * core. DRM core takes care of major-number management and char-dev
845 * registration. A stub ->open() callback forwards any open() requests to the
849 static int drm_stub_open(struct inode
*inode
, struct file
*filp
)
851 const struct file_operations
*new_fops
;
852 struct drm_minor
*minor
;
857 mutex_lock(&drm_global_mutex
);
858 minor
= drm_minor_acquire(iminor(inode
));
860 err
= PTR_ERR(minor
);
864 new_fops
= fops_get(minor
->dev
->driver
->fops
);
870 replace_fops(filp
, new_fops
);
871 if (filp
->f_op
->open
)
872 err
= filp
->f_op
->open(inode
, filp
);
877 drm_minor_release(minor
);
879 mutex_unlock(&drm_global_mutex
);
883 static const struct file_operations drm_stub_fops
= {
884 .owner
= THIS_MODULE
,
885 .open
= drm_stub_open
,
886 .llseek
= noop_llseek
,
889 static int __init
drm_core_init(void)
894 drm_connector_ida_init();
895 idr_init(&drm_minors_idr
);
897 if (register_chrdev(DRM_MAJOR
, "drm", &drm_stub_fops
))
900 ret
= drm_sysfs_init();
902 printk(KERN_ERR
"DRM: Error creating drm class.\n");
906 drm_debugfs_root
= debugfs_create_dir("dri", NULL
);
907 if (!drm_debugfs_root
) {
908 DRM_ERROR("Cannot create /sys/kernel/debug/dri\n");
913 DRM_INFO("Initialized %s %d.%d.%d %s\n",
914 CORE_NAME
, CORE_MAJOR
, CORE_MINOR
, CORE_PATCHLEVEL
, CORE_DATE
);
919 unregister_chrdev(DRM_MAJOR
, "drm");
921 idr_destroy(&drm_minors_idr
);
926 static void __exit
drm_core_exit(void)
928 debugfs_remove(drm_debugfs_root
);
931 unregister_chrdev(DRM_MAJOR
, "drm");
933 drm_connector_ida_destroy();
934 idr_destroy(&drm_minors_idr
);
937 module_init(drm_core_init
);
938 module_exit(drm_core_exit
);